Patent Publication Number: US-10773623-B2

Title: Vehicle seat member and method of manufacturing same

Description:
TECHNICAL FIELD 
     A first invention, a second invention, a third invention, and a fourth invention relate to a vehicle seat member and a method of manufacturing the same. 
     BACKGROUND ART 
     As a core material of a seat of a vehicle such as an automobile, a vehicle seat member in which a frame member is integrally molded on a foamed resin molded body is known (Patent Literatures 1, 2, and the like). 
     Patent Literature 3 discloses a method of manufacturing a vehicle seat core material by embedding a locking fixture to be fixed to a vehicle and a connecting member for connecting it in a thermoplastic resin foamed particle molded body and integrally molding them. The connecting member is embedded on a front side of the foamed particle molded body along a longitudinal direction of the seat core material. Patent Literature 3 discloses that outward in the longitudinal direction of the seat core material of the foamed particle molded body part in which a column part of the locking fixture is embedded, a space or a notch going outward from the column part in the seat core material longitudinal direction is formed. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: JP 2001-161508 A 
     Patent Literature 2: WO2015/159691 
     Patent Literature 3: WO2016/042759 
     SUMMARY OF INVENTION 
     Technical Problem 
     Problem to be Solved by First Invention 
     As described above, in a vehicle seat in a form described in Patent Literatures 1 to 3, a frame member is integrally molded inside a foamed resin molded body constituting a vehicle seat member. Usually, the foamed resin molded body has a property of slightly contracting after releasing from the mold. A degree of contraction after the releasing from the mold is different between the foamed resin molded body and the frame member partially embedded in the foamed resin molded body and thus, the foamed resin molded body or the frame member is deformed after foam molding in some cases. In current vehicles, particularly in automobiles, high dimension accuracy is required for the seat member, and improvement of dimension accuracy after foam molding of the seat member is desirable in order to improve assembling accuracy. 
     Problem to be Solved by Second Invention 
     As described above, in the vehicle seat in the form described in Patent Literatures 1 to 3, the frame member is integrally molded inside the foamed resin molded body constituting the vehicle seat member. Since a material of the frame member and a material of the foamed resin molded body are different kinds of materials, individual thermal expansion coefficients are different. 
     Since the foamed resin constituting the foamed resin molded body has a large difference in an extension amount or a contraction amount due to heat release at the time of the die removal of the foamed resin molded body after the molding or heat input into the vehicle seat member, the frame member can be easily deformed with the foamed resin molded body. 
     In Patent Literature 3, a locking fixture for fixing the seat to the vehicle is located on both ends on a front side of the seat core material, and if the locking fixture is connected by a connecting member embedded in the molded body along a seat longitudinal direction, contraction of the seat core material in the seat longitudinal direction is large and thus, such a problem is described that a dimensional error of the locking fixture is large. As a means for solving this problem, Patent Literature 3 proposes that while a pair of locking fixtures disposed on the both ends on the front side of the seat core material is connected by the connecting member, a space or a notch is formed in a part located on an outer side in the longitudinal direction of a column part of the locking fixture in the foamed resin molded body, % hereby a difference in contraction amounts between the foamed resin molded body and the frame member is absorbed. However, only by providing a space in the vicinity of the column part of the locking fixture, the difference in the contraction amounts between the foamed resin molded body and the frame member cannot be sufficiently absorbed. Moreover, it is likely that the connecting member connecting the locking fixtures to each other is deformed. 
     Problem to be Solved by Third Invention 
     As described above, in the vehicle seat in the form described in Patent Literatures 1 to 3, the frame member is integrally molded inside the foamed resin molded body constituting the vehicle seat member. Since the materials of the frame member and the foamed resin molded body are different, the thermal expansion coefficients are different. Thus, degrees of thermal expansion and thermal contraction are different between the part of the foamed resin where there is no frame member and a part of the foamed resin in which the frame member is embedded in the foamed resin molded body. 
     Therefore, the part of the foamed resin where there is no frame member in the foamed resin molded body is assumed to be slightly deformed from a predetermined shape due to heat release at the time of the die removal of the foamed resin molded body after the molding or heat input into the vehicle seat member, for example. 
     Problem to be Solved by Fourth Invention 
     As described above, in the vehicle seat in the form described in Patent Literatures 1 to 3, the frame member is integrally molded inside the foamed resin molded body constituting the vehicle seat member. Since the materials of the frame member and the foamed resin molded body are different, the thermal expansion coefficients are different. Thus, degrees of thermal expansion and thermal contraction are different between the part of the foamed resin where there is no frame member and a part of the foamed resin in which the frame member is embedded in the foamed resin molded body. 
     Therefore, the part of the foamed resin where there is no frame member in the foamed resin molded body is assumed to be slightly deformed from a predetermined shape due to heat release at the time of the die removal of the foamed resin molded body after the molding or heat input into the vehicle seat member, for example. 
     Solution to Problem 
     &lt;First Invention&gt; 
     A first invention disclosed in the description in order to solve the problems relates to a method of manufacturing a vehicle seat member comprising a foamed resin molded body and a frame member at least a part of which is embedded in the foamed resin molded body, in which 
     the frame member includes a framework extending along a outer shape of the vehicle seat member in plan view, the method of manufacturing a vehicle seat member comprising: 
     a placing step of placing the frame member in a molding die so that the framework extends along the outer shape of the vehicle seat member in plan view: 
     a molding step of molding the foamed resin molded body in the molding die so that at least a part of the frame member is embedded, and 
     a gap forming step of forming a gap between at least a part of the framework and a part of the foamed resin molded body located closer to an outer side and/or an inner side of the vehicle seat member in plan view than the at least a part of the framework, the gap extending along the extending direction of the framework, the gap forming step being performed in the molding step or after the molding step. In this description, the “part of the foamed resin molded body located closer to an outer side and/or an inner side of the vehicle seat member in plan view than the at least a part of the framework” means a “part of the foamed resin molded body opposed to the at least a part of the framework and located closer to the outer side and/or the inner side of the vehicle seat member in plan view than the at least a part of the framework”. In other words, in this description, the part of the foamed resin molded body located closer to the outer side of the vehicle seat member in plan view than the predetermined part of the framework is a part of the foamed resin molded body opposed to the predetermined part and located closer to the outer side of the vehicle seat member in plan view than the predetermined part, and the part of the foamed resin molded body located closer to the inner side of the vehicle seat member in plan view than the predetermined part of the framework is a part of the foamed resin molded body opposed to the predetermined part and located closer to the inner side of the vehicle seat member in plan view than the predetermined part. 
     Since the materials of the frame member and the foamed resin molded body are different, the thermal expansion coefficients are different. In the vehicle seat member in which the foamed resin molded body is integrally molded so that the frame member is embedded, in heat release after the molding of the foamed resin molded body, the degrees of thermal expansion and thermal contraction are different between the part of the frame member and the part of the foamed resin molded body. Particularly, the difference in the degrees of expansion and contraction between the part of the frame member and the part of the foamed resin molded body is usually larger in a width direction in plan view than a thickness direction of the vehicle seat member. Thus, in the case of the vehicle seat member in which the entire framework of the frame member is embedded in contact with the foamed resin molded body, deformation can occur in the foamed resin molded body and the frame member by heat release after the molding of the foamed resin molded body. Particularly, when the framework of the frame member is disposed so as to extend along the outer shape of the vehicle seat member in plan view, influences of the contraction or expansion in the width direction of the foamed resin molded body in plan view on the framework is large. In the method of manufacturing of the first invention, the gap formed between the at least a part of the framework and the part of the foamed resin molded body located at the outer side and/or the inner side of the vehicle seat member in plan view than the at least a part of the framework along the extending direction of the framework can suppress deformation of the foamed resin molded body and the frame member, and a vehicle seat member with excellent dimensional accuracy can be manufactured. 
     In the method of manufacturing of the first invention, to form the gap “along the extending direction” of the framework of the frame member refers to formation of the gap so as to have a shape extended along the extending direction, and the formed gap has a dimension in the extending direction (length) larger than a dimension in a direction (width) perpendicular to the extending direction. 
     In a preferable aspect of the method of manufacturing of the first invention, 
     the framework of the frame member includes a pair of framework opposed parts disposed in the vicinity of a pair of opposed edges in the outer shape of the vehicle seat member so as to oppose to each other and connected to each other; and 
     the gap forming step includes formation of the gap between each of the framework opposed parts and the part of the foamed resin molded body located closer to the outer side of the vehicle seat member in plan view than each of the framework opposed parts. 
     In the foamed resin molded body, portions constituting a pair of opposed edges on the outer shape of the vehicle seat member tend to contract inward, respectively, after the molding. Thus, a pair of framework opposed parts disposed in the vicinity of the pair of edges and fixed to each other are pressed by the inward contraction of the foamed resin molded body in the periphery, respectively, and the contraction of the foamed resin molded body in the periphery of each of the framework opposed parts tends to be non-uniform, and particularly the foamed resin molded body and the frame member are deformed easily. This problem can occur particularly remarkably when the outer shape of the vehicle seat member has a shape having a transverse direction and a longitudinal direction and the extending direction of each of the framework opposed parts crosses the longitudinal direction. In this preferable aspect of the method of manufacturing of the first invention, the problem is solved by forming a gap on the outer side of each of the framework opposed parts, and the gap can suppress deformation of the foamed resin molded body and the frame member. 
     In another preferable aspect of the method of manufacturing of the first invention, 
     the gap forming step includes formation of the gap on the entire periphery of the framework on a section perpendicular to the extending direction of the framework (or the gap forming step includes formation of the gap between the framework and a part of the foamed resin molded body surrounding the entire periphery of the framework on the section perpendicular to the extending direction of the framework). 
     On the framework disposed in the foamed resin molded body, a force associated with the contraction of the foamed resin molded body after molding can act from each direction in the periphery. Particularly if the outer shape of the vehicle seat member has a shape having a transverse direction and a longitudinal direction and the extending direction of the framework is a direction along the longitudinal direction, a shearing force by the large contraction of the foamed resin molded body in the longitudinal direction acts on the framework of the frame member. In this preferable aspect of the method of manufacturing of the first invention, the gap formed in the part surrounding the entire periphery of the framework of the frame member on the section can effectively reduce the contraction of the foamed resin molded body after molding which may affect the framework of the frame member. 
     In another preferable aspect of the method of manufacturing of the first invention, 
     the outer shape of the vehicle seat member has a rectangular shape; 
     the framework of the frame member includes two or more framework corner parts connected to each other and extending along each of two or more corners selected from four corners of the outer shape, wherein the two or more corners are selected so as to constitute one or more pairs of corners opposed in a direction of any one side of the outer shape; and 
     the gap forming step includes formation of the gap along the extending direction of each of the framework corner parts between each of the framework corner parts and a part of the foamed resin molded body located closer to an outer side and/or an inner side of the vehicle seat member in plan view than each of the framework corner parts, the gap forming step being performed during molding or after molding of the foamed resin molded body. 
     In the vehicle seat member including the frame member including the framework corner part having a structure as above and the foamed resin molded body, since degrees of thermal expansion and thermal contraction are different between the part of the frame member and the part of the foamed resin molded body in heat release after molding of the foamed resin molded body, forces are applied from various directions to each of the framework corner parts disposed along each of the sides of the frame member, and the contraction or expansion of the foamed resin molded body becomes non-uniform in the vicinity of each of the framework corner parts, which causes deformation of the frame member and the foamed resin molded body. In this preferable aspect of the method of manufacturing of the first invention, a gap formed between each of the framework corner part and the foamed resin molded body can reduce the action of the force by the contraction or expansion of the foamed resin molded body after molding in a width direction in plan view to each of the framework corner part. 
     In another preferable aspect of the method of manufacturing of the first invention, 
     the vehicle seat member further includes a tubular body embedded in the foamed resin molded body in a state where at least a part of the framework of the frame member is inserted through the tubular body: 
     the placing step includes placing the frame member and the tubular body in the molding die in a state where at least a part of the framework of the frame member is inserted through the tubular body so that a gap is formed between at least a part of the framework of the frame member and an inner peripheral surface of the tubular body; and 
     the gap forming step includes molding of the foamed resin molded body in the molding die in the molding step. 
     According to this preferable aspect of the method of manufacturing of the first invention, a gap can be formed easily between at least a part of the framework of the frame member and the inner peripheral surface of the tubular body. Moreover, positions and the number of the gaps can be easily controlled. Moreover, according to this preferable aspect of the method of manufacturing of the first invention, since the gap is formed in the periphery of the framework of the frame member without losing mechanical strength of the foamed resin molded body, the vehicle seat member with high mechanical strength can be manufactured. 
     In another preferable aspect of the method of manufacturing of the first invention, 
     the frame member further includes a locking portion fixed to the framework and having a distal end part protruding to an outside from the foamed resin molded body; and 
     in the vehicle seat member, the entire periphery of a base end part of the locking portion of the frame member is embedded in the foamed resin molded body. 
     The vehicle seat member manufactured in this preferable aspect of the method of manufacturing of the first invention has high resistance to the force in a direction in which the locking portion is pulled out of the foamed resin molded body since the entire periphery of the base end part of the locking portion used for fixation to the vehicle is embedded in the foamed resin molded body. 
     In another preferable aspect of the method of manufacturing of the first invention, 
     the foamed resin molded body is a molded body containing a foamed polystyrene-based resin or a foamed composite resin comprising a polystyrene-based resin and a polyolefin-based resin. 
     The foamed polystyrene-based resin or the foamed composite resin comprising the polystyrene-based resin and the polyolefin-based resin has small degrees of thermal expansion and thermal contraction, and thus, this aspect is particularly preferable from a viewpoint of suppressing the deformation of the vehicle seat member. 
     In another preferable aspect of the method of manufacturing of the first invention. 
     in the vehicle seat member, at least a part of the framework is disposed in the vicinity of one of end surfaces of the foamed resin molded body in a thickness direction; and 
     the gap forming step is a step of forming a groove with a bottom in the foamed resin molded body, wherein the groove extends along the at least a part of the framework, is opened to the one of end surface and accommodates the at least a part of the framework. 
     According to this aspect of the method of manufacturing of the first invention, since the gap is formed in the periphery of the framework of the frame member without losing the mechanical strength of the foamed resin molded body, the vehicle seat member having high mechanical strength can be manufactured. 
     The first invention disclosed in the description in order to solve the problem further relates to a vehicle seat member including: 
     a foamed resin molded body and a frame member at least a part of which is embedded in the foamed resin molded body, in which 
     the frame member includes a framework extending inside the foamed resin molded body along the outer shape of the vehicle seat member in plan view; and 
     a gap is formed along the extending direction of the framework between at least a part of the framework and a part of the foamed resin molded body located closer to an outer side and/or an inner side of the vehicle seat member in plan view than the at least apart of the framework. 
     When a heat is input into the vehicle seat member in which the foamed resin molded body is integrally molded so that the frame member is embedded (or when the input heat is released), degrees of thermal expansion and thermal contraction are different between the part of the frame member and the part of the foamed resin molded body, and the frame member and the foamed resin molded body can be deformed. Particularly, a difference in the degrees of expansion and contraction between the part of the frame member and the part of the foamed resin molded body is usually larger in the width direction in plan view than in the thickness direction of the vehicle seat member. In the vehicle seat member of the first invention, since the gap is formed between at least a part of the framework of the frame member and the part of the foamed resin molded body located closer to the outer side and/or the inner side of the vehicle seat member in plan view than the at least a part of the framework, the foamed resin molded body and the frame member are not deformed easily when the heat is input (or when the input heat is released), and dimensional accuracy is excellent. 
     In the vehicle seat member of the first invention, the gap formed “along the extending direction” of the framework of the frame member has a shape extending along the extending direction, and a dimension in the extending direction (length) is larger than a dimension in a direction (width) perpendicular to the extending direction. 
     In the preferable aspect of the vehicle seat member of the first invention, 
     the framework of the frame member includes a pair of framework opposed parts disposed in the vicinity of a pair of opposed edges of the outer shape of the vehicle seat member so as to oppose to each other and connected to each other; and 
     the gap is formed between each of the framework opposed parts and the part of the foamed resin molded body located closer to the outer side of the vehicle seat member in plan view than each of the framework opposed parts. 
     In the preferable aspect of the vehicle seat member of the first invention, since the gap is formed on the outer side of each of the pair of framework opposed parts embedded in the foamed resin molded body, the foamed resin molded body and the frame member are not deformed easily. This effect is particularly remarkable when the outer shape of the vehicle seat member has the transverse direction and the longitudinal direction, and the extending direction of each of the framework opposed parts crosses the longitudinal direction. 
     In another preferable aspect of the vehicle seat member of the first invention, 
     on a section perpendicular to the extending direction of the framework, the gap is formed on the entire periphery of the framework (or the gap is formed between the framework and the part of the foamed resin molded body surrounding the entire periphery of the framework on a section perpendicular to the extending direction of the framework). 
     In this preferable aspect of the vehicle seat member of the first invention, since the gap is formed on the entire part surrounding the framework of the frame member on the section, an influence of the contraction or expansion of the foamed resin molded body on the framework of the frame member is effectively reduced, and deformation of the foamed resin molded body and the frame member is particularly small. Particularly, if the outer shape of the vehicle seat member has a shape having the transverse direction and the longitudinal direction and the extending direction of the framework follows the longitudinal direction, an action of the shearing force by large contraction or expansion along the longitudinal direction on the framework in the foamed resin molded body is suppressed, which is preferable. 
     In another preferable aspect of the vehicle seat member of the first invention 
     the outer shape of the vehicle seat member has a rectangular shape, 
     the framework of the frame member includes two or more framework corner parts connected to each other and extending along each of two or more corners selected from four corners of the outer shape, wherein the two or more corners are selected so as to constitute one or more pairs of corners opposed in a direction of any one side of the outer shape; and 
     the gap is formed, along the extending direction of each of the framework corner parts between each of the framework corner parts and a part of the foamed resin molded body located closer to an outer side and/or an inner side of the vehicle seat member in plan view than each of the framework corner parts. 
     In this preferable aspect of the vehicle seat member of the first invention, since the gap is formed between each of the framework corner parts and the part of the foamed resin molded body located closer to an outer side and/or an inner side of the vehicle seat member in plan view than each of the framework corner parts, an influence of the force by the contraction or expansion of the foamed resin molded body in the width direction in plan view in the foamed resin molded body on the framework corner part is small, and the foamed resin molded body and the frame body are not deformed easily. 
     In another preferable aspect of the vehicle seat member of the first invention, 
     the vehicle seat member further includes a tubular body embedded in the foamed resin molded body in a state where at least a part of the framework of the frame member is inserted through the tubular body: and 
     the gap is formed between at least a part of the framework of the frame member and an inner peripheral surface of the tubular body. 
     In this preferable aspect of the vehicle seat member of the first invention, since the foamed resin molded body and the framework are separated by the gap formed in the tubular body, the foamed resin molded body and the frame member are not deformed easily, and dimensional accuracy is excellent. Moreover, in this preferable aspect of the vehicle seat member of the first invention, since the gap is formed in the periphery of the framework of the frame member without losing mechanical strength of the foamed resin molded body, the mechanical strength is high, which is preferable. 
     In another preferable aspect of the vehicle seat member of the first invention, 
     the frame member further includes a locking portion fixed to the framework and having a distal end part protruding to the outside from the foamed resin molded body, and 
     the entire periphery of a base end part of the locking portion is embedded in the foamed resin molded body. 
     In this preferable aspect of the vehicle seat member of the first invention, since the entire periphery of the base end part of the locking portion used for fixation to the vehicle is embedded in the foamed resin molded body, resistance to the force in a direction in which the locking portion is pulled out of the foamed resin molded body is high. 
     In another preferable aspect of the vehicle seat member of the first invention, 
     the foamed resin molded body is a molded body containing a foamed polystyrene-based resin or a foamed composite resin comprising a polystyrene-based resin and a polyolefin-based resin. 
     The foamed polystyrene-based resin or the foamed composite resin comprising the polystyrene-based resin and the polyolefin-based resin have small degrees of thermal expansion and thermal contraction, and thus, this aspect is particularly preferable from a viewpoint of suppressing the deformation of the vehicle seat member. 
     In another preferable aspect of the vehicle seat member of the first invention, 
     at least a part of the framework is disposed in the vicinity of one of end surfaces of the foamed resin molded body in a thickness direction; and 
     the gap is a space in a groove with a bottom formed in the foamed resin molded body so as to extend along at least a part of the framework, to be opened to the one of end surface and to accommodate the at least a part of the framework. 
     According to this aspect of the vehicle seat member of the first invention, since the gap is formed in the periphery of the framework of the frame member without losing the mechanical strength of the foamed resin molded body, the mechanical strength is high, which is preferable. 
     &lt;Second Invention&gt; 
     One or more embodiments of a second invention disclosed in the description in order to solve the problems to be solved by the second invention include the following (2-1): 
     (2-1) 
     A method of manufacturing a vehicle seat member including a frame member and a foamed resin molded body in which the frame member is embedded, the method of manufacturing a vehicle seat member including: 
     a placing step of placing the frame member in a molding die so that the frame member extends along an outer shape of the vehicle seat member in plan view of the vehicle seat member; and 
     a molding step of molding the foamed resin molded body in which the frame member is embedded in the molding die, in which 
     the frame member includes a linear framework disposed along the outer shape and a first locking fixture and a second locking fixture fixed to different positions in the extending direction in which the framework is extended; 
     at least one of sections sandwiched by the first locking fixture and the second locking fixture in the framework is separated to a first part extending such that the first locking fixture is fixed to one end side and another end is located between the first locking fixture and the second locking fixture and a second part extending such that the second locking fixture is fixed to the one end side and another end is located between the first locking fixture and the second locking fixture; and 
     the first locking fixture and the second locking fixture in the frame member include a part embedded in the foamed resin molded body and a part protruding outward from the foamed resin molded body, respectively. 
     Since the materials of the foamed resin of the foamed resin molded body and the frame member embedded in the foamed resin molded body constituting the vehicle seat member have different thermal expansion coefficients, this difference in the thermal expansion coefficients can appear easily as a difference in contraction amounts between the foamed resin molded body and the frame member during cooling after the molding step. Particularly, in the vehicle seat member in which the frame member having a plurality of locking fixtures for fixation to the vehicle partially protruding to the outside of the foamed resin molded body fixed to the linear framework is embedded in the foamed resin molded body, structures of a pair of the locking fixtures and a section of the framework sandwiched by them in the frame member is complicated. Due to this complexity, thermal contraction or thermal expansion does not occur uniformly in the foamed resin molded body in which it is embedded. Thus, deformation of the pair of locking fixtures and the section of the framework sandwiched by them in the frame member and/or the foamed resin molded body in which they are embedded is particularly remarkable. 
     Thus, in the second invention, in the linear framework in the frame member, at least one of the sections sandwiched by the first locking fixture and the second locking fixture is separated to the first part extending such that the first locking fixture is fixed to the one end side and the other end is located between the first locking fixture and the second locking fixture and the second part extending such that the second locking fixture is fixed to the one end side and the other end is located between the first locking fixture and the second locking fixture. The other end side of the first part and the other end side of the second part are not connected. By using the frame member having this constitution, a difference in the contraction between the foamed resin molded body and the frame member can be absorbed between the other end side of the first part and the other end side of the second part. As a result, when a heat during molding of the foamed resin molded body is released, deformation of the frame member and/or the foamed resin molded body caused by the thermal contraction can be suppressed, and the entire shape of the vehicle seat member can be kept to a predetermined shape. 
     A more preferable aspect of the method of the second invention includes the following (2-2): 
     (2-2) 
     The method of manufacturing a vehicle seat member described in (2-1), using the frame member in which the other end of the first part is located at a position closer to the first locking fixture than the other end of the second part in the extending direction as the frame member. 
     In the frame member used in this aspect, the other end of the first part and the other end of the second part in the framework are separated in the extending direction. Thus, in this aspect of the method of the second invention, the difference in the contraction amounts between the foamed resin molded body and the frame member can be absorbed by the separation part between the other end of the first part and the other end of the second part. 
     A more preferable aspect of the method of the second invention includes the following (2-3): 
     (2-3) 
     The method of manufacturing a vehicle seat member described in (2-1), using the frame member in which the other end of the first part is located at a position closer to the second locking fixture than the other end of the second part in the extending direction as the frame member: and 
     the other end side of the first part and the other end side of the second part are disposed so as to be juxtaposed in a direction perpendicular to the extending direction. 
     In the frame member used in this aspect, the other end side of the first part and the other end side of the second part in the framework are disposed so as to be juxtaposed in the direction perpendicular to the extending direction, and thus, the first part and the second part are disposed without disconnection in the extending direction between the first locking fixture and the second locking fixture, and thus, in the vehicle seat member in which this frame member is embedded in the foamed resin molded body, mechanical strength is given to a part between the first locking fixture and the second locking fixture of the foamed resin molded body. Moreover, in the framework, at least one of the sections sandwiched by the first locking fixture and the second locking fixture is separated to the first part and the second part. Thus, in this aspect of the method of the invention, the difference in the contraction amounts between the foamed resin molded body and the frame member can be absorbed between the other end side of the first part and the other end side of the second part while the strength of the manufactured vehicle seat member is maintained. 
     A more preferable aspect of the method of the second invention includes the following (2-4): 
     (2-4) 
     The method of manufacturing a vehicle seat member described in any one of (2-1) to (2-3), in which 
     an outer shape of the vehicle seat member in plan view is a shape having a transverse direction and a longitudinal direction: 
     in the placing step, the frame member is placed in the molding die so that at least a part of the framework follows the longitudinal direction; and 
     the frame member used is a frame member in which
         the first locking fixture and the second locking fixture are fixed to different positions in the longitudinal direction on a longitudinal part of the framework which is a part extending along the longitudinal direction; and   the longitudinal part includes the first part and the second part between the first locking fixture and the second locking fixture.       

     Here, when the frame member having a structure in which the first locking fixture and the second locking fixture are fixed to the longitudinal part of the framework extending along the longitudinal direction of the vehicle seat member is embedded in the foamed resin molded body, the thermal contraction amount of the foamed resin molded body in the longitudinal direction is particularly large, and the foamed resin molded body can be thermally contracted easily in the direction in which the first locking fixture and the second locking fixture are brought closer to each other, and a section of the framework sandwiched by the first locking fixture and the second locking fixture is deformed easily so as to be buckled. However, according to this aspect of the method of the second invention, by constituting a portion between the first locking fixture and the second locking fixture in the longitudinal part of the framework by dividing it to the first part and the second part, a difference in the contraction amounts between the foamed resin molded body and the frame member in the longitudinal direction can be absorbed between the other end side of the first part and the other end side of the second part. 
     A more preferable aspect of the method of the second invention includes the following (2-5): 
     (2-5) 
     The method of manufacturing the vehicle seat member described in any one of claims (2-1) to (2-4), in which the frame member is made to circle around along an outer shape of the vehicle seat member in the placing step. 
     According to this aspect of the second invention, since the frame member circles around along the outer shape of the vehicle seat member, strength of the vehicle seat member can be improved. Here, when the frame member circles around along the outer shape of the vehicle seat member, the frame member is restrained by the foamed resin molded body, and accordingly it may be deformed easily by thermal contraction of the foamed resin molded body. Then, in this aspect of the second invention, in the linear framework, by constituting at least one of the sections between the first locking fixture and the second locking fixture by dividing it to the first part and the second part, the difference in the contraction amounts between the foamed resin molded body and the frame member can be absorbed between the other end side of the first part and the other end side of the second part, and the deformation of the foamed resin molded body and the frame member can be suppressed. 
     In the present description, the vehicle seat member is further disclosed as the second invention. 
     The vehicle seat member according to the second invention includes the following (2-6): 
     (2-6) 
     The vehicle seat member including a frame member and a foamed resin molded body in which the frame member is embedded, in which 
     the frame member extends along an outer shape of the vehicle seat member in plan view of the vehicle seat member; 
     the frame member has a linear framework disposed along the outer shape and a first locking fixture and a second locking fixture fixed to different positions in an extending direction in which the framework is extended: 
     at least one of sections sandwiched by the first locking fixture and the second locking fixture in the framework is separated to a first part extending such that the first locking fixture is fixed to one end side and the other end is located between the first locking fixture and the second locking fixture and a second part extended such that the second locking fixture is fixed to the one end side and the other end is located between the first locking fixture and the second locking fixture; and 
     the first locking fixture and the second locking fixture include a part embedded in the foamed resin molded body and a part protruding outward from the foamed resin molded body, respectively. 
     When a heat is input into the vehicle seat member (or when the input heat is released), since the materials of the foamed resin of the foamed resin molded body and the frame member embedded in the foamed resin molded body which are materials of the vehicle seat member have different thermal expansion coefficients, this difference in the thermal expansion coefficients can appear easily as a difference in expansion amounts or contraction amounts between the foamed resin molded body (rim part) and the frame member. Particularly, in the vehicle seat member in which the frame member including a part in which a plurality of locking fixtures used for fixation to the vehicle is fixed to the linear framework is embedded in the foamed resin molded body, structures of a pair of the locking fixtures and a part of the framework sandwiched by them in the frame member are complicated. Due to this complexity, thermal contraction or thermal expansion does not occur uniformly in the foamed resin molded body in which it is embedded. Thus, deformation of the foamed resin molded body in the pair of locking fixtures and the part of the framework sandwiched by them in the frame member and/or their vicinities is particularly remarkable. 
     Thus, in the second invention, in the linear framework in the frame member, at least one of the sections sandwiched by the first locking fixture and the second locking fixture is separated to the first part extending such that the first locking fixture is fixed to the one end side and the other end is located between the first locking fixture and the second locking fixture and the second part extending such that the second locking fixture is fixed to the one end side and the other end is located between the first locking fixture and the second locking fixture. The other end side of the first part and the other end side of the second part are not connected. As a result, deformation of the frame member and/or the foamed resin molded body caused by the thermal contraction or thermal expansion can be suppressed, and the entire shape of the vehicle seat member can be kept to a predetermined shape. 
     A more preferable aspect of the vehicle seat member of the second invention includes the following (2-7): 
     (2-7) 
     The vehicle seat member described in (2-6), in which the other end of the first part is at a position closer to the first locking fixture than the other end of the second part in the extending direction. 
     In this aspect, since the other end of the first part and the other end of the second part in the framework are separated in the extending direction, the difference in the contraction amounts between the foamed resin molded body and the frame member can be absorbed by a separation part between the other end of the first part and the other end of the second part. 
     A more preferable aspect of the vehicle seat member of the second invention includes the following (2-8): 
     (2-8) 
     The vehicle seat member described in (2-6), in which 
     the other end of the first part is at a position closer to the second locking fixture than the other end of the second part in the extending direction, and 
     the other end side of the first part and the other end side of the second part are disposed so as to be juxtaposed in a direction perpendicular to the extending direction. 
     In this aspect, since the other end side of the first part and the other end side of the second part in the framework are disposed so as to be juxtaposed in the direction perpendicular to the extending direction, the first part and the second part are disposed without disconnection in the extending direction between the first locking fixture and the second locking fixture, and thus, in this vehicle seat member in which the frame member is embedded in the foamed resin molded body, mechanical strength is given to the part between the first locking fixture and the second locking fixture of the foamed resin molded body. Moreover, in the framework, at least one of the sections sandwiched by the first locking fixture and the second locking fixture is separated to the first part and the second part. Thus, in this aspect, the difference in the contraction amounts or expansion amounts between the foamed resin molded body and the frame member can be absorbed between the other end side of the first part and the other end side of the second part, while strength of the vehicle seat member to be manufactured is held. 
     A more preferable aspect of the vehicle seat member of the second invention includes the following (2-9): 
     (2-9) 
     The vehicle seat member described in any one of (2-6) to (2-8), in which 
     an outer shape of the vehicle seat member in plan view has a shape having a transverse direction and a longitudinal direction, 
     at least a part of the framework extends along the longitudinal direction. 
     the first locking fixture and the second locking fixture are fixed to different positions in the longitudinal direction on a longitudinal part of the framework which is a part extending along the longitudinal direction, and 
     the longitudinal part includes the first part and the second part between the first locking fixture and the second locking fixture. 
     Here, if the frame member with the structure in which the first locking fixture and the second locking fixture are fixed to the longitudinal part of the framework along the longitudinal direction of the vehicle seat member is embedded in the foamed resin molded body, the thermal contraction amount of the foamed resin molded body in the longitudinal direction is particularly large, and accordingly the foamed resin molded body can be thermally contracted easily in the direction in which the first locking fixture and the second locking fixture get closer to each other, and the section of the framework sandwiched by the first locking fixture and the second locking fixture is deformed easily so as to be buckled. However, according to this aspect of the second invention, since the space between the first locking fixture and the second locking fixture in the longitudinal part of the framework is constituted to be divided into the first part and the second part, the difference in the contraction amounts or expansion amounts between the foamed resin molded body and the frame member in the longitudinal direction can be absorbed between the other end side of the first part and the other end side of the second part. Thus, the vehicle seat member of this aspect has high dimensional stability as the whole. 
     A more preferable aspect of the vehicle seat member of the second invention includes the following (2-10): 
     (2-10) 
     The vehicle seat member described in any one of (2-6) to (2-9), in which the frame member circles around along the outer shape of the vehicle seat member. According to this Aspect of the Second Invention, Since the Frame Member Circles around along the outer shape of the vehicle seat member, strength of the vehicle seat member can be improved. Here, if the frame member is made to circle around along the outer shape of the vehicle seat member, the frame member is restrained by the foamed resin molded body, and accordingly it is deformed easily by thermal contraction of the foamed resin molded body. Then, in this aspect of the second invention, at least one of the sections between the first locking fixture and the second locking fixture in the linear framework is constituted by the first part and the second part, and thus, the difference in the contraction amounts between the foamed resin molded body and the frame member can be absorbed between the other end side of the first part and the other end side of the second part, and the deformation of the foamed resin molded body and the frame member can be suppressed. 
     &lt;Third invention&gt; 
     A method of manufacturing a vehicle seat member according to a third invention disclosed in the description in order to solve the problems includes the following (3-1): 
     (3-1) 
     A method of manufacturing a vehicle seat member including a frame member and a foamed resin molded body in which at least a part of the frame member is embedded, including 
     a placing step of placing the frame member in a molding die so that the frame member extends along an outer shape of the vehicle seat member in plan view of the vehicle seat member, and 
     a molding step of molding the foamed resin molded body in a molding die so that the foamed resin molded body has a rim part embedding at least a part of the frame member and having an outer shape of the vehicle seat member and an extension extending inward from the rim part so as to bridge the rim part inside of the rim part, wherein 
     in the molding step, the foamed resin molded body is molded so that the extension includes a foamed resin with a maximum point stress by bending larger than that of the foamed resin contained in a not-connecting part other than a connecting part connected to the extension in the rim part. 
     In the method of manufacturing the vehicle seat member, apparent thermal contraction amounts are different between the rim part of the foamed resin molded body embedding at least a part of the frame member and the extension extending inside the rim part and embedding no frame member. As a result, a compression stress and a tensile stress are non-uniformly applied as a thermal stress on the extension surrounded by the rim part, and the extension is deformed easily. The third invention can suppress such deformation. 
     In other words, in the third invention, by molding the foamed resin molded body so that the extension contains a foamed resin with the maximum point stress by bending larger than the foamed resin contained in the not-connecting part of the rim part, rigidity of the extension is improved more than the not-connecting part of the rim part, and deformation of the extension by the stress acting on the extension is suppressed. As a result, even if the foamed resin molded body including the rim part and the extension is thermally contracted during the molding or after the molding, deformation of the extension can be suppressed. Moreover, the maximum point stress by bending of the foamed resin can be easily controlled by a means such as changing an expansion ratio, for example. Thus, the vehicle seat member with high dimensional accuracy can be easily manufactured. As another means for suppressing deformation of the extension, increasing of the maximum point stress by bending of the entire foamed resin molded body including the extension and the rim part (referred to as “another means 1”), increasing of a thickness of the extension (referred to as “another means 2”) can be considered, for example. However, according to the other means 1, there is a possibility of a weight increase of the entire foamed resin molded body, a cost increase, or other disadvantages. According to the other means 2, the design of the extension is limited and accordingly there is a possibility that the applications are limited. Since these possibilities are low in the third invention, it is remarkably advantageous as compared to the other means 1 and 2. 
     A preferable aspect of the method of manufacturing the vehicle seat member according to the third invention includes the following (3-2): 
     (3-2) 
     The method of manufacturing the vehicle seat member described in (3-1), in which 
     the frame member has a continuous part including opposed parts across a space inside of the rim part, and 
     the molding step forms the extension so as to extend between the opposed parts. 
     Since the frame member has the continuous part, both sides of the extension are restrained by a part of the rim part in which the continuous part is embedded. In this structure, the extension is deformed particularly easily by thermal contraction, but in this aspect of the third invention, by molding the foamed resin molded body so that the extension extends between the opposed parts of the continuous structure in the molding step, the deformation of the extension can be suppressed. 
     A more preferable aspect of the method of manufacturing the vehicle seat member according to the third invention includes the following (3-3): 
     (3-3) 
     The method of manufacturing the vehicle seat member described in (3-1) or (3-2), in which 
     the outer shape of the vehicle seat member in plan view has a shape having a transverse direction and a longitudinal direction, and 
     in the molding step, the extension includes a first extension part extending at least along the longitudinal direction between opposed parts of the rim part, and the foamed resin molded body is molded so that the first extension part contains a foamed resin with a maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part in the rim part. 
     The first extension part formed along the longitudinal direction is deformed easily by thermal contraction, but in this aspect, by molding the foamed resin molded body so that the first extension part contains the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part in the rim part, the deformation of the first extension part can be suppressed. 
     A further preferable aspect of the method of manufacturing the vehicle seat member according to the third invention includes the following (3-4): 
     (3-4) 
     The method of manufacturing the vehicle seat member described in any one of (3-1) to (3-3), in which 
     in the placing step, at least a part of the frame member is made to circle around along the outer shape of the vehicle seat member. 
     According to this aspect, since the frame member circles around along the outer shape of the vehicle seat member, strength of the vehicle seat member can be improved. Moreover, by causing the frame member to circle around along the outer shape of the vehicle seat member, the both sides of the extension is restrained and the extension is deformed easily by thermal contraction, but according to this aspect, by molding the foamed resin molded body so that the extension contains the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the rim part, rigidity of the extension can be improved, and deformation of the extension by the stress acting on the extension can be suppressed. 
     The third invention further relates to the vehicle seat member. 
     The vehicle seat member according to the third invention includes the following (3-5): 
     (3-5) 
     A vehicle seat member including a frame member and a foamed resin molded body in which at least a part of the frame member is embedded, in which 
     the frame member extends along the outer shape of the vehicle seat member in plan view of the vehicle seat member, 
     the foamed resin molded body includes a rim part embedding at least a part of the frame member and having an outer shape of the vehicle seat member and an extension extending inward from the rim part so as to bridge the rim part inside of the rim part, and 
     in the foamed resin molded body, the extension contains a foamed resin with a maximum point stress by bending larger than that of a foamed resin contained in a not-connecting part other than a connecting part connected to the extension in the rim part. 
     When a heat is input into the vehicle seat member (or when the input heat is released), apparent thermal expansion amounts (or thermal contraction amounts) are different between the rim part of the foamed resin molded body embedding the frame member and the extension extending inside the rim part and embedding no frame member. As a result, a compression stress and a tensile stress are non-uniformly applied as a thermal stress on the extension surrounded by the rim part, and the extension is deformed easily. The third invention can suppress such deformation. 
     In other words, in the third invention, by causing the extension extending inside the rim part to contain the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part in the rim part, rigidity of the extension is improved more than that of the rim part, deformation of the extension can be suppressed, and dimensional accuracy of the vehicle seat member can be ensured. As another means for suppressing deformation of the extension, the other means 1 and 2, for example, can be considered. However, according to the other means 1, there is a possibility of a weight increase of the entire foamed resin molded body, a cost increase, or other disadvantages. According to the other means 2, the design of the extension is limited and accordingly there is a possibility that the applications are limited. Since these possibilities are low in the third invention, it is remarkably advantageous as compared to the other means 1 and 2. 
     A more preferable aspect of the vehicle seat member according to the third invention includes the following (3-6): 
     (3-6) 
     The vehicle seat member described in (3-5), in which the frame member has a continuous part including opposed parts across a space inside of the rim part, and the extension extends between the opposed parts. 
     Since the frame member has the continuous part, both sides of the extension are restrained by a part of the rim part in which the continuous part is embedded. When a heat is input into the vehicle seat member with this structure (or when the input heat is released), the extension is deformed particularly easily by thermal contraction, but in this aspect of the third invention, since the extension contains the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part in the rim part, the extension is not deformed easily. 
     A more preferable aspect of the vehicle seat member according to the third invention includes the following (3-7): 
     (3-7) 
     The vehicle seat member described in (3-5) or (3-6), in which the outer shape of the vehicle seat member in plan view has a shape having a transverse direction and a longitudinal direction, 
     the extension includes a first extension part along the longitudinal direction extending between opposed parts of the rim part, and 
     the first extension part includes a foamed resin with a maximum point stress by bending larger than that of a foamed resin contained in the not-connecting part in the rim part. 
     The first extension part extending along the longitudinal direction is deformed easily by thermal contraction. But according to this aspect, since the first extension part includes the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part in the rim part, the first extension part is not deformed easily. 
     A more preferable aspect of the vehicle seat member according to the third invention includes the following (3-8): 
     (3-8) 
     The vehicle seat member described in any one of (3-5) to (3-7), in which the frame member circles around along the outer shape of the vehicle seat member. 
     According to this aspect, since the frame member circles around along the outer shape of the vehicle seat member, strength of the vehicle seat member is high. Moreover, by causing the frame member to circle around along the outer shape of the vehicle seat member, the both sides of the extension is restrained and the extension is deformed easily by thermal contraction. But according to this aspect, since the extension contains the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the rim part, rigidity of the extension is high, and deformation of the extension is effectively suppressed. 
     &lt;Fourth Invention&gt; 
     In order to solve the problem, the method of manufacturing a vehicle seat member according to a fourth invention disclosed in the description includes the following (4-1): 
     (4-1) 
     A method of manufacturing a vehicle seat member including a frame member and a foamed resin molded body in which at least a part of the frame member is embedded, in which 
     the frame member includes a framework and a reinforcing portion, 
     the foamed resin molded body includes a rim part having an outer shape of the vehicle seat member and an extension extending inward from the rim part so as to bridge the rim part inside of the rim part, the method of manufacturing a vehicle seat member comprising 
     a placing step of placing the frame member in a molding die so that the framework is placed at a position embedded in the rim part of the foamed resin molded body along the outer shape of the vehicle seat member in plan view and the reinforcing portion is placed at a position embedded in the extension along the extending direction of the extension of the foamed resin molded body; and 
     a molding step of molding, in the molding die, the foamed resin molded body including the rim part in which the framework is embedded and the extension in which the reinforcing portion is embedded. 
     In the method of manufacturing the vehicle seat member, if the framework of the frame member is embedded in the rim part having the outer shape of the vehicle seat member and a part of the frame member is not embedded in the extension extending inside surrounded by the rim part in the foamed resin molded body, apparent thermal contraction amounts are different between the rim part and the extension of the foamed resin molded body during the molding or after the molding. As a result, a compression stress and a tensile stress non-uniformly acts as a thermal stress on the extension surrounded by the rim part, and the extension is deformed easily. 
     Thus, in the fourth invention, by molding the foamed resin molded body by in-mold foam molding so that the framework of the frame member is embedded in the rim part of the foamed resin molded body, and the reinforcing portion of the frame member is embedded along the extending direction of the extension in the extension of the foamed resin molded body, deformation of the extension by the stress acting on the extension is suppressed. As a result, even if the foamed resin molded body including the rim part and the extension is thermally contracted during the molding or after the molding, deformation of the extension can be suppressed. As a result, a vehicle seat member with high dimensional accuracy can be manufactured. 
     A preferable aspect of the method of manufacturing the vehicle seat member according to the fourth invention includes the following (4-2); (4-2) 
     The method described in (4-1), in which the reinforcing portion is a linear reinforcing portion having both ends linked with the framework, respectively, in the frame member. 
     In this aspect, since the framework is reinforced by the reinforcing portion in the frame member, rigidity of the framework is improved, and the frame member has a structure which is hard to be deflected in general. As a result, in the placing step, the frame member can be placed in the molding die easily. Particularly when the frame member is placed in the molding die by using a robot, the frame member is hard to be deflected, and thus, placement is easy. 
     A more preferable aspect of the method of manufacturing the vehicle seat member according to the fourth invention includes the following (4-3): 
     (4-3) 
     the method described in (4-1) or (4-2), in which the framework of the frame member has a continuous part including opposed parts across a space inside of the rim part, and 
     the molding step includes molding such that the extension has the reinforcing portion embedded and extends between the opposed parts. 
     Since the framework of the frame member has the continuous part, both sides of the extension are restrained by the rim part in which the continuous part is embedded. In this structure, the extension is deformed particularly easily by thermal contraction, but in this aspect of the fourth invention, by molding the extension so as to embed the reinforcing portion of the frame member, deformation of the extension can be suppressed. 
     A further preferable aspect of the method of manufacturing the vehicle seat member according to the fourth invention includes the following (4-4): 
     (4-4) 
     The method of manufacturing the vehicle seat member described in any one of (4-1) to (4-3), in which the outer shape of the vehicle seat member in plan view has a shape having a transverse direction and a longitudinal direction, 
     the extension molded in the molding step has the reinforcing portion embedded and includes a first extension part extending along at least the longitudinal direction between opposed parts of the rim part. 
     The first extension part formed along the longitudinal direction is deformed easily by thermal contraction, but according to this aspect, by embedding the reinforcing portion of the frame member in the first extension part, deformation of the first extension part can be suppressed. 
     A further preferable aspect of the method of manufacturing the vehicle seat member according to the fourth invention includes the following (4-5): 
     (4-5) 
     The method of manufacturing the vehicle seat member described in any one of (4-1) to (4-4), in which in the placing step, a part including the framework of the frame member is made to circle around along the outer shape of the vehicle seat member. 
     According to this aspect, since the frame member circles around along the outer shape of the vehicle seat member, strength of the vehicle seat member can be improved. Moreover, when the frame member is made to circle around along the outer shape of the vehicle seat member, both sides of the extension are restrained and the extension is easily deformed by thermal contraction, but according to this aspect, by embedding the reinforcing portion of the frame member in the extension, deformation of the extension can be suppressed. 
     The fourth invention further relates to a vehicle seat member. 
     The vehicle seat member according to the fourth invention includes the following (4-6): 
     (4-6) 
     A vehicle seat member including a frame member and a foamed resin molded body in which at least a part of the frame member is embedded, in which 
     the frame member includes a framework and a reinforcing portion, 
     the foamed resin molded body includes a rim part having an outer shape of the vehicle seat member and an extension extending inward from the rim part so as to bridge the rim part inside of the rim part, 
     the framework of the frame member is disposed so as to be embedded in the rim part of the foamed resin molded body along the outer shape of the vehicle seat member in plan view, and 
     the reinforcing portion of the frame member is disposed so as to be embedded in the extension along the extending direction of the extension of the foamed resin molded body. 
     In the vehicle seat member, if the framework of the frame member is embedded in the rim part having the outer shape of the vehicle seat member and a part of the frame member is not embedded in the extension extending inside surrounded by the rim part in the foamed resin molded body, when a heat is input into the vehicle seat member (or when the input heat is released), apparent thermal expansion amounts (thermal contraction amounts) are different between the rim part and the extension of the foamed resin molded body. As a result, a compression stress and a tensile stress acts non-uniformly as a thermal stress on the extension surrounded by the rim part in which the framework of the frame member is embedded, and the extension is deformed easily. But in the fourth invention, by embedding the reinforcing portion of the frame member in the extension along the extending direction of the extension, deformation of the extension can be suppressed. 
     A preferable aspect of the vehicle seat member according to the fourth invention includes the following (4-7): 
     (4-7) 
     The vehicle seat member described in (4-6), in which the reinforcing portion is a linear reinforcing portion having both ends connected to the framework, respectively, in the frame member. 
     In this aspect, since the framework is reinforced by the reinforcing portion in the frame member, rigidity of the framework is improved, and the frame member has a structure which is hard to be deflected in general. In the vehicle seat member of this aspect, even if the foamed resin molded body and the frame member are thermally expanded or thermally contracted to degrees different from each other when a heat is input (or when the input heat is released), the foamed resin molded body and the frame member are hard to be deformed particularly. 
     A more preferable aspect of the vehicle seat member according to the fourth invention includes the following (4-8): 
     (4-8) 
     the vehicle seat member described in (4-6) or (4-7), in which the framework of the frame member has a continuous part including opposed parts across a space inside of the rim part, and 
     the extension of the foamed resin molded body has the reinforcing portion embedded and extends between the opposed parts. 
     Since the framework of the frame member has the continuous part, the both sides of the extension are restrained by a part of the rim part in which the continuous part is embedded. When a heat is input into the vehicle seat member with this structure (or when the input heat is released), the extension is deformed particularly easily by thermal contraction or thermal expansion, but in this aspect of the fourth invention, since the reinforcing portion of the frame member is embedded in the extension, the extension is hard to be deformed. 
     A more preferable aspect of the vehicle seat member according to the fourth invention includes the following (4-9): 
     (4-9) 
     the vehicle seat member described in any one of (4-6) to (4-8), in which the outer shape of the vehicle seat member in plan view has a shape having a transverse direction and a longitudinal direction, and 
     the extension includes a first extension part having the reinforcing portion embedded and extending along the longitudinal direction between opposed parts of the rim part. 
     The first extension part formed along the longitudinal direction is deformed easily by thermal contraction or thermal expansion but according to this aspect, since the reinforcing portion of the frame member is embedded in the first extension part, the first extension part is hard to be deformed. 
     A more preferable aspect of the vehicle seat member according to the fourth invention includes the following (4-10): 
     (4-10) 
     The vehicle seat member described in any one of (4-6) to (4-9), in which a part including the framework of the frame member circles around along the outer shape of the vehicle seat member. 
     According to this aspect, since the frame member circles around along the outer shape of the vehicle seat member, strength of the vehicle seat member is high. Moreover, when the frame member is made to circle around along the outer shape of the vehicle seat member, the both sides of the extension are restrained and the extension is deformed easily by thermal contraction or thermal expansion, but according to this aspect, since the reinforcing portion of the frame member is embedded in the extension, deformation of the extension is effectively suppressed. 
     The present description includes disclosed contents of JP Patent Application No. 2016-157925, Japan Patent Application No. 2016-160230, JP Patent Application No. 2016-165049, and JP Patent Application No. 2016-167108 on which priority of this application is based. 
     Advantageous Effects of Invention 
     Advantageous Effects of First Invention 
     According to the first invention, in the method of manufacturing the vehicle seat member including the foamed resin molded body and the frame member at least a part of which is embedded therein, deformation of the foamed resin molded body and the frame member caused by contraction of the foamed resin molded body after molding can be suppressed, and the vehicle seat member with excellent dimensional accuracy can be manufactured. 
     Moreover, according to the vehicle seat member according to the first invention, even when a heat is input into the vehicle seat member or the input heat is released, the dimensional accuracy of the vehicle seat member can be ensured. 
     Advantageous Effects of Second Invention 
     According to the method of manufacturing the vehicle seat member according to the second invention, the vehicle seat member with high dimensional accuracy can be obtained. Moreover, according to the vehicle seat member according to the second invention, even when a heat is input into the vehicle seat member or the input heat is released, deformation caused by them can be suppressed. 
     Advantageous Effects of Third Invention 
     According to the method of manufacturing the vehicle seat member according to the third invention, the vehicle seat member with high dimensional accuracy can be obtained. Moreover, according to the vehicle seat member according to the third invention, even when a heat is input into the vehicle seat member or the input heat is released, the dimensional accuracy of the vehicle seat member can be ensured. 
     Advantageous Effects of Fourth Invention 
     According to the method of manufacturing the vehicle seat member according to the fourth invention, the vehicle seat member with high dimensional accuracy can be obtained. Moreover, according to the vehicle seat member according to the fourth invention, even when a heat is input into the vehicle seat member or the input heat is released, the dimensional accuracy of the vehicle seat member can be ensured. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view for explaining a structure of a frame member of a vehicle seat member according to a first embodiment of a first invention. 
         FIG. 2  is a perspective view for explaining a structure of a foamed resin molded body of the vehicle seat member according to the first embodiment of the first invention. 
         FIG. 3  is a side view of the vehicle seat member according to the first embodiment of the first invention. 
         FIG. 4  is a plan view (bottom view) of the vehicle seat member according to the first embodiment of the first invention when seen from a bottom surface (vehicle fastened surface). 
         FIG. 5  is a I-I line arrow-view sectional view illustrated in  FIG. 4  of the vehicle seat member according to the first embodiment of the first invention. 
         FIG. 6  is a II-II line arrow-view sectional view illustrated in  FIG. 4  of the vehicle seat member according to the first embodiment of the first invention. 
         FIG. 7  are schematic sectional views at a position corresponding to the I-I line arrow-view section illustrated in  FIG. 4  of the vehicle seat member according to the first embodiment of the first invention for explaining a manufacturing method.  FIG. 7(A)  is a sectional view of a state where pre-expanded resin particles are filled in a molding die,  FIG. 7(B)  is a sectional view of a state where the pre-expanded resin particles are expanded from the state illustrated in  FIG. 7(A) , and a foamed resin molded body is molded, and  FIG. 7(C)  is a view illustrating a state where the foamed resin molded body is removed from the molding die from the state illustrated in  FIG. 7(B) . 
         FIG. 8  is a plan view (bottom view) of the vehicle seat member according to a second embodiment of the first invention when seen from a bottom surface (vehicle fastened surface). 
         FIG. 9   FIG. 9  is a III-III line arrow-view sectional view illustrated in  FIG. 8  of the vehicle seat member according to the second embodiment of the first invention. 
         FIG. 10   FIG. 10  is a IV-IV line arrow-view sectional view illustrated in  FIG. 8  of the vehicle seat member according to the second embodiment of the first invention. 
         FIG. 11(A)  is a sectional view of a part of a region X illustrated in  FIG. 8  of the vehicle seat member according to the second embodiment of the first invention at a height going through a second framework rear part.  FIG. 11(B)  is a sectional view of a part corresponding to the region X illustrated in  FIG. 8  at the height going through the second framework rear part when a gap is not provided in the vehicle seat member according to the second embodiment of the first invention. 
         FIG. 12  is a plan view (bottom view) of the vehicle seat member according to a third embodiment of the first invention when seen from the bottom surface (vehicle fastened surface). 
         FIG. 13  is a V-V line arrow-view sectional view illustrated in  FIG. 12  of the vehicle seat member according to the third embodiment of the first invention. 
         FIG. 14  is a schematic sectional view for explaining a method of manufacturing the vehicle seat member according to the third embodiment of the first invention. 
         FIG. 15  are schematic sectional views for explaining a method of manufacturing a vehicle seat member which is a comparative example of the first invention.  FIG. 15(A)  is a schematic sectional view of a state where pre-expanded resin particles are expanded and a foamed resin molded body is molded, and  FIG. 15(B)  is a schematic sectional view illustrating a state where the foamed resin molded body is removed from the molding die from the state illustrated in  FIG. 15(A) . 
         FIG. 16  is a schematic perspective view of a vehicle seat member according to a first embodiment of a second invention when seen from below. 
         FIG. 17  is a schematic perspective view illustrating a placed state of a frame member of the vehicle seat member illustrated in  FIG. 16 . 
         FIG. 18  is a left side view of the vehicle seat member illustrated in  FIG. 16 . 
         FIG. 19  is a view of the vehicle seat member illustrated in  FIG. 16  when seen from an upper surface. 
         FIG. 20  are schematic sectional views at a position corresponding to a I-I line arrow-view section illustrated in  FIG. 19 .  FIG. 20( a )  is a sectional view of a state where pre-expanded particles are filled in a molding die,  FIG. 20( b )  is a sectional view of a state where the pre-expanded resin particles are expanded from the state illustrated in  FIG. 19( a ) , and a foamed resin molded body is molded, and  FIG. 20( c )  is a view illustrating a state where the foamed resin molded body is removed from the molding die from the state illustrated in  FIG. 20( b ) . 
         FIG. 21  are views for explaining a method of manufacturing a vehicle seat member which is a comparative example of the second invention, in which  FIG. 21( a )  is a sectional view of a state where pre-expanded resin particles are expanded and a foamed resin molded body is molded, and  FIG. 21( b )  is a view illustrating a state where the foamed resin molded body is removed from the molding die from the state illustrated in  FIG. 21( a ) . 
         FIG. 22  is a schematic perspective view illustrating a placed state of the frame member of the vehicle seat member according to a second embodiment of the second invention. 
         FIG. 23  is a schematic conceptual diagram for explaining vicinities of another end side of a first member and another end side of a second member according to the second embodiment corresponding to  FIG. 20( c ) . 
         FIG. 24  is a schematic perspective view for explaining a structure of a frame member when a vehicle seat member according to a first embodiment of a third invention is seen from below. 
         FIG. 25  is a schematic perspective view for explaining a structure of a foamed resin molded body when the vehicle seat member according to the first embodiment of the third invention is seen from below. 
         FIG. 26  is a left side view of the vehicle seat member according to the first embodiment of the third invention. 
         FIG. 27  is a plan view of the vehicle seat member according to the first embodiment of the third invention when seen from an upper surface. 
         FIG. 28  are schematic sectional views at a position corresponding to a I-I line arrow-view sectional view illustrated in  FIG. 27  for explaining a method of manufacturing the vehicle seat member according to the first embodiment of the third invention.  FIG. 28(A)  is a schematic sectional view of a state where pre-expanded resin particles are filled in a molding die.  FIG. 28(B)  is a schematic sectional view of a state where the pre-expanded resin particles are expanded from the state illustrated in  FIG. 28(A)  and a foamed resin molded body is molded.  FIG. 28(C)  is a schematic sectional view illustrating a state where the foamed resin molded body is removed from the molding die from the state illustrated in  FIG. 28(B) . 
         FIG. 29  are schematic sectional views at a position corresponding to a II-II line arrow-view sectional view illustrated in  FIG. 27  for explaining the method of manufacturing the vehicle seat member according to the first embodiment of the third invention.  FIG. 29(A)  is a schematic sectional view of a state where the pre-expanded resin particles are filled in the molding die.  FIG. 29(B)  is a schematic sectional view of a state where the pre-expanded resin particles are expanded from the state illustrated in  FIG. 29(A)  and the foamed resin molded body is molded.  FIG. 29(C)  is a schematic sectional view illustrating a state where the foamed resin molded body is removed from the molding die from the state illustrated in  FIG. 29(B) . 
         FIG. 30  are schematic sectional views for explaining a method of manufacturing a vehicle seat member which is a comparative example of the third invention. 
         FIG. 30(A)  is a schematic sectional view of a state where pre-expanded resin particles are expanded and a foamed resin molded body is molded.  FIG. 30(B)  is a schematic sectional view illustrating a state where the foamed resin molded body is removed from a molding die from the state illustrated in  FIG. 30(A) . 
         FIG. 31  is a schematic perspective view for explaining a structure of a frame member when a vehicle seat member according to a second embodiment of the third invention is seen from below. 
         FIG. 32  is a schematic perspective view for explaining a structure of a foamed resin molded body when the vehicle seat member according to the second embodiment of the third invention is seen from below. 
         FIG. 33  is a schematic perspective view for explaining a structure of a frame member when a vehicle seat member according to a first embodiment of a fourth invention is seen from below. 
         FIG. 34  is a schematic perspective view for explaining a structure of a foamed resin molded body when the vehicle seat member according to the first embodiment of the fourth invention is seen from below. 
         FIG. 35  is a plan view of the vehicle seat member according to the first embodiment of the fourth invention when seen from an upper surface. 
         FIG. 36  is a left side view of the vehicle seat member according to the first embodiment of the fourth invention. 
         FIG. 37  are schematic sectional views at a position corresponding to a I-I line arrow-view sectional view illustrated in  FIG. 36  for explaining a method of manufacturing the vehicle seat member according to the first embodiment of the fourth invention.  FIG. 37(A)  is a schematic sectional view of a state where pre-expanded particles are filled in a molding die.  FIG. 37(B)  is a schematic sectional view of a state where the pre-expanded particles are expanded from the state illustrated in  FIG. 37(A)  and a foamed resin molded body is molded.  FIG. 37(C)  is a schematic sectional view illustrating a state where the foamed resin molded body is removed from the molding die from the state illustrated in  FIG. 37(B) . 
         FIG. 38  are schematic sectional views for explaining a method of manufacturing a vehicle seat member which is a comparative example.  FIG. 38(A)  is a schematic sectional view of a state where pre-expanded particles are expanded and a foamed resin molded body is molded.  FIG. 38(B)  is a schematic sectional view illustrating a state where the foamed resin molded body is removed from a molding die from the state illustrated in  FIG. 38(A) . 
         FIG. 39  is a schematic perspective view for explaining a structure of a frame member when a vehicle seat member according to a second embodiment of the fourth invention is seen from below. 
         FIG. 40  is a schematic perspective view for explaining a structure of a foamed resin molded body when the vehicle seat member according to the second embodiment of the fourth invention is seen from below. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     &lt;Materials for Preparing Foamed Resin Molded Body&gt; 
     In a first invention, a second invention, a third invention, and a fourth invention, a “foamed resin molded body” refers to a molded body in which pre-expanded resin particles obtained by being pre-expanded expandable resin particles containing a resin and a foaming agent are filled in a molding die, and the pre-expanded resin particles are refoamed in the molding die so as to be foamed/molded in the molding die. 
     Materials constituting each part of the foamed resin molded body are called a “foamed resin” in the first invention, the second invention, the third invention, and the fourth invention. 
     The “resin”, the “foaming agent”, the “expandable resin particles”, and the “pre-expanded resin particles” will be specifically described. 
     (Resin) 
     Resins are not particularly limited, but thermoplastic resins are usually used, and a composite resin containing a polystyrene-based resin and a polyolefin-based resin, a polystyrene-based resin, a polyolefin-based resin, a polyester-based resin, and the like can be used, for example. 
     The expandable resin particles are the resin particles impregnated with a foaming agent, and they may be impregnated with the foaming agent at the same time as formation by polymerization of the resin or may be impregnated with the foaming agent after the polymerization of the resin. 
     The resin particles which can be suitably used in the first invention, the second invention, the third invention, and the fourth invention and the expandable resin particles obtained by impregnating the resin particles with the foaming agent will be described below in detail. 
     (Composite Resin Particles Containing Polystyrene-Based Resin and Polyolefin-Based Resin) 
     The composite resin particles contain the polyolefin-based resin and the polystyrene-based resin. 
     A shape of the composite resin particle is preferably spherical, oval spherical (egg-shaped), or columnar, for example. 
     Moreover, an average grain size is not particularly limited but 0.3 to 7 mm can be exemplified. 
     Furthermore, a ratio (L/D) between a maximum diameter L and a minimum diameter D of the composite resin particle is not particularly limited but it is preferably 1 to 1.6. 
     (1) Polyolefin-Based Resin 
     Examples of the polyolefin-based resin include a resin containing a unit derived from an olefin monomer having 2 to 10 carbon atoms such as polypropylene, polyethylene, and the like. The polyolefin-based resin may be a single polymer of an olefin monomer or may be a copolymer with another monomer which can be co-polymerized with the olefin monomer. Moreover, the polyolefin-based resin may be cross-linked. Examples of the copolymer include a copolymer of vinyl acetate and ethylene (EVA). As the polyolefin-based resin, a resin having an average mass molecular amount of 18 to 500 thousands, for example, can be used. 
     (2) Polystyrene-Based Resin 
     Examples of the polystyrene-based resin include resins derived from styrene and styrene-based monomers of substituted styrene (substituents are lower alkyl, halogen atoms (particularly chlorine atoms), and the like), for example. Examples of the substituted styrene include α-methylstyrene, p-methylstyrene, t-butylstyrene, ethylstyrene, i-propylstyrene, dimetylstyrene, vinyltoluene, chlorostyrene bromostyrene, and the like. Moreover, the polystyrene-based resin may be a copolymer of a styrene-based monomer and another monomer capable of copolymerization with the styrene-based monomer. Examples of the other monomer include acrylonitrile, (meth) alkyl acrylate ester (having approximately 1 to 8 carbon atoms of an alkyl part), divinyl benzene, mono or di (meth) acrylic ester of ethylene glycol, maleic anhydride, N-phenylmaleimide, and the like. 
     When another monomer is used, it is preferably used within a range of 30 mass parts or less to 100 mass parts of the styrene-based monomer. 
     The polystyrene-based resin is more preferably a resin derived only from styrene. 
     (3) Contents of Polyolefin-Based Resin and Polystyrene-Based Resin 
     The content of the polystyrene-based resin is 120 to 400 mass parts, for example, or preferably 150 to 250 mass parts, to 100 mass parts of the polyolefin-based resin. 
     (4) Other Additives 
     Other additives may be contained in the composite resin particles. Examples of the other additive include a nucleating agent, a coloring agent, a flame retardant, a flame retardant aid, an oxidation inhibitor, an ultraviolet ray absorber, scale-state silicates, and the like. 
     (5) Method of Manufacturing Composite Resin Particles 
     The composite resin particles may be manufactured by any method only if the polyolefin-based resin and the polystyrene-based resin can be contained in particles. For example, examples of such methods include a method in which the both resins are kneaded in an extruder and the kneaded products are cut, a method in which seed particles containing the polyolefin-based resin are impregnated with a styrene-based monomer in an aqueous medium and then, the monomers are polymerized, and the like. Among them, the latter method is preferable from a viewpoint that the both resins can be mixed more uniformly and particles closer to spheres can be obtained. Here, the composite resin particles obtained by the latter method are also called polyolefin-modified polystyrene-based resin particles or simply modified resin particles. 
     (6) Commercial Composite Resin Particles 
     As the composite resin particles containing the polystyrene-based resin and the polyolefin-based resin, commercial products can be also purchased and used. The commercial products of the composite resin particles containing the polystyrene-based resin and the polyolefin-based resin include Piocelan (registered trademark): OP-30EU, OP-30ELV by Sekisui Plastics Co., Ltd., and the like. 
     (Polystyrene-Based Resin Particles) 
     (1) Polystyrene-Based Resin 
     Examples of the polystyrene-based resins constituting the polystyrene-based resin particles are not particularly limited but include single polymers of styrene-based monomers such as styrene, α-methylstyrene, vinyltoluene, chlorostyrene, ethylstyrene, i-propylstyrene, dimethylstyrene, bromostyrene, and the like or their copolymers of two or more kinds of these monomers and the like, and the polystyrene-based resins having 50 mass % or more of a styrene component is preferable and polystyrene is more preferable. 
     Moreover, the polystyrene-based resins may be a copolymer of the styrene-based monomer as a main component and a vinyl monomer which can be copolymerized with this styrene-based monomer. Examples of such vinyl monomers include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, cetyl (meth) acrylate, and the like and bifunctional monomers such as (meth) acrylonitrile, dimethylmaleate, dimethylfumarate, diethylfumarate, ethylfumarate, and the like, and divinyl benzene, alkylene glycol dimethacrylate, and the like. 
     Moreover, in the polystyrene-based resin, other additives listed in (4) of the aforementioned (composite resin particles containing polystyrene-based resin and polyolefin-based resin) may be contained. 
     The shape of the polystyrene-based resin particles used for the first invention, the second invention, the third invention, and the fourth invention is not particularly limited, but a spherical shape is preferable, and a particle diameter is preferably 0.3 to 2.0 mm or 0.3 to 1.4 mm from a viewpoint of filling easiness of polystyrene-based resin pre-expanded particles into a molding die which will be described later. Moreover, if the shape is columnar, a volume preferably corresponds to the aforementioned a preferred grain size. Furthermore, a styrene-converted weight average molecular amount (Mw) of the polystyrene-based resin can be within a range of 120 thousands to 600 thousands. 
     (2) Method of Manufacturing Polystyrene-Based Resin Particles 
     The manufacturing methods of the polystyrene-based resin particles which are materials of the foamed polystyrene-based resin particles are not particularly limited and include a method of manufacturing the polystyrene-based resin particles in which the polystyrene-based resin is supplied to an extruder and molten and kneaded, then extruded in a strand shape from the extruder, cooled, and then cut into a predetermined length each (strand cutting method), a method of manufacturing the polystyrene-based resin particles in which it is extruded into water through a hole of a mouth mounted at a tip end of the extruder and at the same time cut and cooled (under-water hot-cut method), and the like. Moreover, the scale-state silicates or metal oxides are diffused in a resin in this extruder and then, the resin is cut into the predetermined length each so as to have the polystyrene-based resin particles. Moreover, such a method may be employed that the polystyrene-based resin particles are manufactured by a seed polymerization method in which the styrene-based monomer is impregnated with the polystyrene-based resin seed particles in an underwater suspension with the polystyrene-based resin particles obtained as above as seed particles and then, a foaming agent is added to the manufactured polystyrene-based resin particles. 
     (3) Commercial Polystyrene-Based Resin Particles 
     Commercial products can be also purchased and used as the polystyrene-based resin particles. Examples of the commercial products containing the polystyrene-based resin particles include Eslen-beads: FDK-40LV, ESDK by Sekisui Plastics Co., Ltd., and the like. 
     (Other Resin Particles) 
     For other resin particles, the composite resin particles containing the polystyrene-based resin and the polyolefin-based resin described above in detail or the resin particle having a shape similar to the polystyrene-based resin particle can be used, and similar other additives can be contained as appropriate. 
     Examples of the other resin particles include the polyolefin-based resin particles and polyester-based resin particles. Examples of the polyolefin-based resin particles include the particles of the aforementioned polyolefin-based resin as a component contained in the composite resin particles containing the polystyrene-based resin and the polyolefin-based resin. Examples of the polyester-based resin constituting the polyester-based resin particle includes polyethylene terephthalate. 
     As methods of manufacturing particles containing these other resins, a general method is used similarly to the composite resin particles containing the polystyrene-based resin and the polyolefin-based resin described above in detail or the polystyrene-based resin particles. 
     Commercial products may be purchased and used also for the particles containing the other resins. 
     (Expandable Resin Particles) 
     The foaming agent contained in the expandable resin particles is not particularly limited and any well-known agent can be used. Particularly, organic compounds which have a boiling point at a softening point or less of the used resin and are in a gas-state or a liquid-state at a normal pressure are suitable. Examples of the foaming agent include hydrocarbons such as propane, n-butane, isobutene, n-pentane, isopentane, neopentane, cyclopentane, cyclopentadiene, n-hexane, petroleum ether, and the like. These foaming agents may be used singularly or two or more kinds may be used at the same time. As the foaming agent, hydrocarbon is preferable and propane, n-butane, isobutane, n-pentane, isopentane, and the like are more preferable. 
     A content of the foaming agent in the expandable resin particles is not particularly limited but typically, it is 5 to 25 mass parts to 100 mass parts of the expandable resin particles. The content of the foaming agent in the expandable resin particles is measured after being left for five days in a thermostatic chamber at 13° C. immediately after the manufacture. 
     (Method of Manufacturing Expandable Resin Particles) 
     The impregnation of the foaming agent into the resin particles may be performed into the particles after polymerization of the resin or into the particles in the middle of the polymerization. The impregnation in the middle of the polymerization can be performed by a method of impregnation in an aqueous medium (wet impregnation method). The impregnation after the polymerization can be performed by the wet impregnation method or by a method of impregnation under absence of a medium (dry impregnation method). The impregnation in the middle of the polymerization is usually performed in a second half of the polymerization preferably. The second half of polymerization is preferably after 70 mass % of a constituent monomer has been polymerized. Moreover, after 99 mass % of the constituent monomer has polymerized, the foaming agent can be impregnated subsequently to the polymerization. 
     An impregnation temperature of the foaming agent can be set to 50 to 140° C. 
     The impregnation of the foaming agent may be performed under presence of a foaming aid. Examples of the foaming aids include solvents such as toluene, xylene, ethylbenzene, cyclohexane, and plasticizers such as di-isobutyl adipate, diacetylated monolaurate, coconut oil, and the like (high-boiling solvent). An added amount of the foaming aid is preferably 0.2 to 2.5 mass parts to 100 mass parts of the resin particles. 
     Surface treatment agents (binding inhibitors, fusion promoters, anti-static agents, spreaders, and the like) may be added into a system in impregnation of the foaming agent as necessary. Examples of added amounts (total value) of these surface treatment agents include 0.01 to 2 mass parts to 100 mass parts of the resin particles. 
     (Pre-Expanded Resin Particles) 
     The expandable resin particles are made into pre-expanded resin particles (referred to also simply as foamed resin particles) having a large number of pores by being foamed (pre-expanding) by using steam or other means in a foaming apparatus (pre-expanding apparatus). 
     Bulk expansion ratio of the pre-expanded resin particles can be adjusted in accordance with an expansion ratio of a targeted foamed resin. 
     (In-Mold Foam Molding) 
     Conditions of in-mold foam molding will be described in description of the following embodiments of each of the inventions. 
     &lt;First Invention&gt; 
     Hereinafter, a vehicle seat member according to the first invention and embodiments of the vehicle seat will be described by referring to the drawings. However, a range of the first invention is not limited to individual embodiments. 
     First Invention First Embodiment 
     A first embodiment of a vehicle seat member and a method of manufacturing the same will be described on the basis of  FIGS. 1 to 7 . 
     A vehicle seat member  1  includes a foamed resin molded body  100  and a frame member  200  a part of which is embedded in the foamed resin molded body  100  as a basic constitution. 
     An entire shape of the vehicle seat member  1  is not particularly limited but an outer shape  400  of the vehicle seat member  1  in plan view is generally a rectangular shape. In the description, a rectangle refers to a square such as a rectangle, a regular square, and the like, and not only the rectangle or the regular square, it may be a shape such as a trapezoid or a parallelogram. In the description, the rectangle also includes a substantial rectangle, and corner parts may be rounded or a part or the whole of a side constituting the rectangle may be a bent side, for example. 
     The illustrated foamed resin molded body  100  has a bottom surface  140  which is a side fastened to a vehicle and an upper surface  150  which is a side on which a user of the vehicle is seated. The illustrated foamed resin molded body  100  is constituted by a front part  120  and a rear part  130  formed to be continuously connected to a rear end portion  122  of the front part  120  and to extend diagonally upward from the rear end portion  122 . When being assembled in the vehicle, the front part  120  of the foamed resin molded body  100  supports a thigh part of a user, while the rear part  130  supports a buttock part of the user. The upper surface  150  of the foamed resin molded body  100  is formed so as to hold the thigh part and the buttock part of the user by being a curved surface dented to a vehicle side so that a vicinity of the rear end portion  122  of the front part  120  becomes a deepest part in the illustrated embodiment. However, the shape and a thickness of the foamed resin molded body  100  can be changed in various ways in accordance with a shape of a vehicle body side on which the vehicle seat member  1  is mounted and are not limited to the illustrated embodiment. The upper surface  150  of the foamed resin molded body  100  may be substantially a flat shape, for example. 
     The foamed resin molded body  100  is an in-mold foamed molded body of a foamed resin. The foamed resin is not particularly limited but a foamed thermoplastic resin is usually used. For example, a foamed polystyrene-based resin, a foamed composite resin containing a polystyrene-based resin and a polyolefin-based resin, a foamed polyolefin-based resin, and the like are suitably used, and the foamed polystyrene-based resin or the foamed composite resin containing the polystyrene-based resin and the polyolefin-based resin is particularly preferable. The foamed polystyrene-based resin or the foamed composite resin containing the polystyrene-based resin and the polyolefin-based resin have small degrees of thermal expansion and thermal contraction and thus, they are particularly preferable from a viewpoint that deformation of the foamed resin molded body and the frame member is suppressed. An expansion ratio can be adjusted as appropriate in accordance with a type of the foamed resin, but it is approximately 10 to 50 times in general or approximately 20 to 40 times typically. 
     The foamed resin molded body  100  includes a rim part  181  defining the outer shape  400  of the vehicle seat member  1  and an extension  182  extending inward from the rim part  181  so as to bridge the rim part  181  inside of the rim part  181 . More specifically, the extension  182  has a first extension part  182 A extending in a longitudinal direction and two second extension parts  182 B,  182 B extending in a transverse direction, and the first extension part  182 A and the two second extension parts  182 B,  182 B are linked by crossing at a linking portion  182 C. In this embodiment, the frame member  200  has a second framework  260  (continuous part) where a second framework right part  201  and a second framework left part  202  which are a pair of framework opposed parts opposed to each other across a space inside the rim part  181  continue to each other, and the first extension part  182 A in the extension  182  is formed so as to extend between the second framework right part  201  and the second framework left part  202 . 
     By providing the first extension part  182 A and the second extension parts  182 B crossing each other inside the rim part  181 , the vehicle seat member  1  can be reinforced. By forming the extension  182  in the space inside the rim part  181 , hollow portions  121 ,  131  are formed in the front part  120  and the rear part  130  of the foamed resin molded body  100 , respectively. The hollow portions  121 ,  131  are provided for the purpose of reducing the weight of the foamed resin molded body  100  and of accommodating the other members (a cushion material which is elastically deformed more easily than the foamed resin molded body  100 , a member of a console box, and the like) constituting the vehicle seat. 
     In the first invention, the foamed resin molded body is not limited to the illustrated form but may be a shape in which the hollow portion is not formed. 
     The outer shape  400  of the vehicle seat member  1  in plan view is a rectangle and includes a right edge  401 , a left edge  402 , a front edge  403 , and a rear edge  404  as four sides and includes a first corner  405 , a second corner  406 , a third corner  407 , and a fourth corner  408  as four corners. 
     The frame member  200  is embedded in order to apply required shape retaining properties and strength to the foamed resin molded body  100 . The frame member  200  is usually constituted by a material whose dimensions are not substantially changed as compared to the foamed resin molded body  100  under a condition that the foamed resin molded body  100  is molded or a metal material such as steel, for example. As the frame member  200 , a wire rod (wire) made of steel having a diameter of approximately 3 to 6 mm is used in general, but it may be a thin-plate shaped steel material. 
     The frame member  200  includes the first framework  250  and a second framework  260  extending inside the foamed resin molded body  100  along the outer shape  400  of the vehicle seat member  1  in plan view and a pair of bases  230  connected to end portions of the first framework  250  and the second framework  260 . 
     The frame member  200  further includes a front locking portion  210  mounted on each of the bases  230  and a rear locking portion  220  mounted on the second framework  260 . In this embodiment, for the first framework  250 , the second framework  260 , the front locking portion  210 , and the rear locking portion  220 , a wire rod (wire) made of steel or aluminum having a diameter of approximately 3 to 6 mm or the like is used, for example, but it may be a band-shaped or tubular steel material made of metal, for example. The first framework  250  and the second framework  260  correspond to the “framework” referred to in the first invention. The “linear” framework is not limited to a wire rod such as a wire but may be the aforementioned band-shaped, tubular, or the like and is not particularly limited as long as it extends along one line. 
     The first framework  250  of the frame member  200  extends along a part of a center of the front edge  403  in its vicinity, and the second framework  260  extends along a part of both sides of the front edge  403 , the right edge  401 , the left edge  402 , the rear edge  404 , the first corner  405 , the second corner  406 , the third corner  407 , and the fourth corner  408  in their vicinities. The frame member  200  is embedded in a spot slightly inward from an outer peripheral surface  160  of the foamed resin molded body  100  defining the outer shape  400  so as to follow the outer shape  400  of the vehicle seat member  1 . 
     As described above, the frame member  200  continuously circles around along the outer shape  400  of the vehicle seat member  1  by the first framework  250 , the second framework  260 , and the pair of bases  230 ,  230  connecting them. In this embodiment, the frame member  200  continuously circles around along the outer shape  400  of the vehicle seat member  1 , but the frame member  200  may intermittently circle around along the outer shape  400  of the vehicle seat member  1 , for example. That is, the framework may be disposed, not limited to this form, only on a part along the outer shape  400 . For example, the frame member  200  may be constituted by the first framework  250  having the bases  230 ,  230  connected to both ends and disposed along the front edge  403 , without presence of the second framework  260 . Moreover, the number of frameworks constituting the frame member  200  is not limited to two, but the number may be one, or three or more. 
     The first framework  250  extends along the front edge  403  in the vicinity of the front edge  403  in plan view of the vehicle seat member  1  and their both ends are connected to the pair of bases  230 ,  230 . The second framework  260  includes a second framework right part  201  disposed along the right edge  401 , a second framework left part  202  disposed along the left edge  402 , a second framework rear part  204  disposed along the rear edge  404 , a second framework first corner part  205  disposed along the first corner  405  and connecting the second framework rear part  204  and the second framework right part  201 , a second framework second corner part  206  disposed along the second corner  406  and connecting the base  230  in the vicinity of the right edge  401  and the second framework right part  201 , a second framework third corner part  207  disposed along the third corner  407  and connecting the base  230  in the vicinity of the left edge  402  and the second framework left part  202 , and a second framework fourth corner part  208  disposed along the fourth corner  408  and connecting the second framework left part  202  and the second framework rear part  204 . 
     The locking portions  210 ,  210 ,  220  are constituted by two front locking portions  210 ,  210  and one rear locking portion  220  in the illustrated embodiment. The front locking portions  210 ,  210  are formed so as to protrude from each of the pair of bases  230  connected to the both ends of the first framework  250  as illustrated in  FIG. 4 , and a distal end part  211  protrudes outward from the foamed resin molded body  100  in each of the front locking portions  210  as illustrated in  FIG. 6 , while a base end part  212  is embedded in the foamed resin molded body  100 . The rear locking portion  220  is formed so as to protrude from the second framework rear part  204 , and a distal end part  221  protrudes outward from the foamed resin molded body  100 , while a base end part  222  is embedded in the foamed resin molded body  100 . The front locking portions  210 ,  210  are connected to the both ends of the first framework  250  through the bases  230 ,  230  in the illustrated embodiment, but this form is not limiting, and as in the rear locking portion  220 , they may be directly connected to the both ends of the first framework  250  without through the bases  230 ,  230 . Moreover, the number of the front locking portions  210 ,  210  is not particularly limited but it may be one, or three or more. Either one of the front locking portions  210 ,  210  and the rear locking portion  220  does not have to be present. 
     In the front locking portions  210 ,  210  and the rear locking portion  220 , their distal end parts  211 ,  221  are used for being fastened to the vehicle. In the illustrated embodiment, the distal end part  211  of each of the front locking portions  210 ,  210  and the distal end part  221  of the rear locking portion  220  are formed by bending a wire rod into a substantial U-shape, respectively, but this structure is not limiting, and it only needs to be a structure capable of being fastened in accordance with the structure on the vehicle side. 
     In this embodiment, as illustrated in  FIG. 6 , the base end part  212  of each of the front locking portions  210  has its entire periphery embedded in the foamed resin molded body  100 . By means of this constitution, when the vehicle seat member  1  of this embodiment is fastened to the vehicle through the distal end part  211  of each of the front locking portions  210 ,  210 , even if a force in a pulling-out direction is applied, the front locking portions  210 ,  210  are held by the foamed resin molded body  100  and thus, resistance against the force in the pulling-out direction is high. When the entire base end part  212  of each of the front locking portions  210  is embedded in the foamed resin molded body  100 , regardless of the aforementioned merit, movement of the foamed resin molded body  100  associated with thermal expansion or thermal contraction is prevented in the vicinity of the base end part  212  of each of the front locking portion  210  and thus, it is likely to lead to deformation of the foamed resin molded body  100  and the frame member  200  but in this embodiment, by providing a gap which will be described later, deformation of the foamed resin molded body  100  and the frame member  200  can be suppressed. 
     In this embodiment, the foamed resin molded body  100  is a substantially rectangle in plan view, and the frameworks  250 ,  260  of the frame member  200  have longitudinal parts (the first framework  250  and the second framework rear part  204 ) along the longitudinal direction of the foamed resin molded body  100 , the locking portion (the front locking portions  210 ,  210  and the rear locking portion  220 ) are provided on the longitudinal part, a body portion of the frame member  200  is constituted only by a pair of opposed longitudinal parts (the first framework  250  and the second framework rear part  204 ), a pair of transverse parts (the second framework right part  201  and the second framework left part  202 ) connected to both sides of each of the longitudinal parts and a part connecting them (the second framework first corner part  205 , the second framework second corner part  206 , the second framework third corner part  207 , the second framework fourth corner part  208 , and the bases  230 ,  230 ), and the body portion of the frame member  200  circles around inside the foamed resin molded body  100  so that a continuous loop is formed inside the foamed resin molded body  100  along the outer shape  400  of the foamed resin molded body  100  in plan view. By means of this constitution, rigidity of the vehicle seat member  1  of this embodiment can be improved. 
     The vehicle seat member  1  of this embodiment having the aforementioned constitution can be a vehicle seat  10  by laminating/disposing an upper seat member  50  made of a cushion material or the like as appropriate from a side of an upper surface  150  of the vehicle seat member  1  as illustrated in  FIG. 3 , for example. Moreover, the vehicle seat member  1  may be covered by an appropriate exterior material together with the upper seat member  50  so as to have the vehicle seat  10 . 
     The vehicle seat member  1  of this embodiment has gaps  101 ,  101 ,  102 ,  102  formed between at least a part of the second framework  260  and the foamed resin molded body  100  along the extending direction of the second framework  260 . In the following description, an outer side of the vehicle seat member  1  in plan view is expressed simply as an “outer side”, and an inner side of the vehicle seat member  1  in plan view is expressed simply as an “inner side” in some cases. In the second framework  260 , on a section (see  FIG. 5 ) perpendicular to the extending direction of the second framework right part  201 , the gaps  101 ,  101  are formed between the second framework right part  201 , and a part  112  of the foamed resin molded body  100  located closer to the outer side than the second framework right part  201  and a part  113  of the foamed resin molded body  100  located closer to the inner side than the second framework right part  201  and, on a section perpendicular to the extending direction of the second framework left part  202 , gaps  102 ,  102  are formed between the second framework left part  202  and a part of the foamed resin molded body  100  located closer to the outer side and the inner side than the second framework left part  202 . The part  112  of the foamed resin molded body  100  located closer to the outer side than the second framework right part  201  and the part  113  of the foamed resin molded body  100  located closer to the inner side than the second framework right part  201  are adjacent in a width direction of the vehicle seat member  1  in plan view to the second framework right part  201 , respectively. One of the gaps  101 ,  101  is formed between the second framework right part  201  and the front part  120  of the foamed resin molded body  100 , while another is formed between the second framework right part  201  and the rear part  130  of the foamed resin molded body  100 . The gaps  102 ,  102  around the second framework left part  202  are also formed similarly. 
     In the first invention, the gap between at least a part of the framework and the foamed resin molded body is preferably formed so as to have a length of 50% or more of a width of the vehicle seat member in the extending direction along the extending direction of the at least a part of the framework from a viewpoint of effective suppression of deformation of the vehicle seat member. Specifically, a total of the lengths of the gaps  101 ,  101  is preferably 50% or more of the width (the width between the front edge  403  and the rear edge  404  of the vehicle seat member  1 ) of the vehicle seat member  1  in the extending direction of the second framework right part  201 . Similarly, the total of the lengths of the gaps  102 ,  102  is preferably 50% or more of the width (the width between the front edge  403  and the rear edge  404  of the vehicle seat member  1 ) of the vehicle seat member  1  in the extending direction of the second framework left part  202 . 
     When a heat is input into the aforementioned vehicle seat member  1  (or when the input heat is released), since materials of the foamed resin of the foamed resin molded body  100  and the frame member  200  embedded in the foamed resin molded body  100  which are materials of the vehicle seat member  1  have different thermal expansion coefficients, this difference in the thermal expansion coefficients can easily appear as a difference in the expansion amounts or contraction amounts between (the rim part  181  of) the foamed resin molded body  100  and the frame member  200 . Particularly, this phenomenon is remarkable in the width direction (or particularly in the longitudinal direction) of the foamed resin molded body  100  in plan view of the vehicle seat member  1 . 
     However, in this embodiment, in the second framework  260 , by providing the gaps  101 ,  101 ,  102 ,  102  between the second framework right part  201  as well as the second framework left part  202  and the foamed resin molded body  100 , a difference in the contraction amounts between the foamed resin molded body  100  and the frame member  200  can be absorbed in the gaps  101 ,  101 ,  102 ,  102 . As a result, deformation of the frame member  200  and the foamed resin molded body  100  in which the frame member  200  is embedded can be suppressed. 
     Particularly, the extension  182  (particularly, the first extension part  182 A) in which the frame member  200  is not disposed but constituted only of the foamed resin can be deformed easily so as to be curved from the center thereof. According to this embodiment, even in such case, the entire shape of the vehicle seat member  1  can be kept to a predetermined shape. 
     The method of manufacturing the vehicle seat member  1  of this embodiment includes: 
     the placing step of placing the frame member  200  in a molding die  70  which will be described later so that the first framework  250  and the second framework  260  are disposed along the outer shape  400  in plan view of the vehicle seat member  1 ; 
     the molding step of molding the foamed resin molded body  100  in the in-mold foam molding so that at least a part of the frame member  200  is embedded by filling the pre-expanded resin particles obtained by pre-expanding the expandable resin particles containing the resin and the foaming agent and then, by foaming the pre-expanded resin particles in the molding die  70 ; and 
     the gap forming step of forming the gaps  101 ,  101 ,  102 ,  102  between at least a part of the first framework  250  or the second framework  260  and the part  112  of the foamed resin molded body  100  located closer to the outer side than the at least a part as well as the part  113  of the foamed resin molded body  100  located closer to the inner side than the at least a part along the extending direction of the first framework  250  or the second framework  260 , the gap forming step being performed in the molding step or after the molding step. After the molding step, the molding die  70  is removed, and the vehicle seat member  1  containing the foamed resin molded body  100  is manufactured. 
     Usually, the foamed resin molded body  100  has a property of slightly contacting after molding. On the other hand, the frame member  200  constituted by a material such as metal whose dimensions are not substantially changed as compared to the foamed resin molded body  100  under a condition of molding the foamed resin molded body  100  is not substantially changed in the dimensions before and after molding of the foamed resin molded body  100 . Thus, if the entirety of the first framework  250  and the second framework  260  of the frame member  200  embedded in the foamed resin molded body  100  is in close contact with the foamed resin molded body  100 , the first framework  250  and the second framework  260  are subjected to the force by the contraction of the foamed resin molded body  100 , the foamed resin molded body  100  can no longer contract uniformly in the vicinity of the first framework  250  and the second framework  260 , and as a result, deformation such as warping, bending, or the like of the frame member  200  and the foamed resin molded body  100  can occur. 
     The contraction amount of the foamed resin molded body  100  from the outside to the inside of the outer shape  400  of the vehicle seat member  1  in plan view is usually larger than the contraction amount of the foamed resin molded body  100  in the thickness direction. Thus, as in the illustrated embodiment, when the first framework  250  and the second framework  260  are disposed so as to extend inside the foamed resin molded body  100  along the outer shape  400  of the vehicle seat member  1  in plan view, an influence of the contraction of the foamed resin molded body  100  on the first framework  250  and the second framework  260  is large, and the aforementioned problem of the deformation of the frame member  200  and the foamed resin molded body  100  becomes apparent. 
     Moreover, the foamed resin molded body  100  includes the rim part  181  and the extension  182  and is formed so that a plurality of the hollow portions  121 ,  131  penetrate the foamed resin molded body  100 , as described above. Problems of a comparative example in which the gap forming step is not performed will be described by referring to  FIG. 15 . Each of  FIG. 15  is a view corresponding to the VI-VI line arrow-view sectional view in  FIG. 4  (however, this is an example in which the gaps  101 ,  101 ,  102 ,  102  are not formed). As illustrated in  FIG. 15(A) , the foamed resin molded body  100  is molded by a molding die  7  made of a first die  71  and a second die  72 , and as illustrated in  FIG. 15(B) , for a period from immediately after the molding until the foamed resin molded body  100  is removed from the molding die  7  and the foamed resin molded body  100  releases heat, the foamed resin molded body  100  thermally contracts. The amount of contraction is particularly larger in the width direction of the foamed resin molded body  100  of the vehicle seat member  1  in plan view. At this time, both sides of the first extension part  182 A of the extension  182  where the frame member  200  is not present are restrained by the rim part  181  where the second framework  260  of the frame member  200  is present and thus, a compression stress and a tensile stress non-uniformly act as a thermal stress on the extension  182 , and the extension  182  is deformed easily so as to be curved upward from the center. 
     Thus, in this embodiment, in the molding of or after the molding of the foamed resin molded body  100 , by forming the gaps  101 ,  101 ,  102 ,  102  between at least a part of the first framework  250  and the second framework  260  of the frame member  200  and the part  112  of the foamed resin molded body  100  located closer to the outer side than the at least a part and/or the part  113  of the foamed resin molded body  100  located closer to the inner side than the at least part along the extending direction of the first framework  250  and the second framework  260 , the force by the contraction after the molding of the foamed resin molded body  100  is buffered by the gaps, and the influence on the frame member  200  is reduced. 
     Patent Literature 3 discloses that, as described above, a space is formed outside in the longitudinal direction of the seat core material of the foamed particle molded body part in which a column part of the locking fixture is embedded but the column part of the locking fixture is disposed perpendicularly to a spreading direction of the foamed particle molded body and cannot solve the aforementioned problems to be solved by this embodiment. Moreover, with the constitution of Patent Literature 3, a holding force of the column part of the locking fixture by the foamed particle molded body is likely to be lowered by forming the space. 
     In the second framework  260  of the frame member  200  in this embodiment, the second framework right part  201  and the second framework left part  202  are disposed so as to oppose to each other in the longitudinal direction of the vehicle seat member  1 , respectively, and are continuously integrated. In this case, even though the second framework right part  201  and the second framework left part  202  are pushed inward by inward contraction of the respective peripheral foamed resin molded body  100 , since relative positions of the second framework right part  201  and the second framework left part  202  are fixed, the frame member  200  is deformed easily. Moreover, since the contraction of the foamed resin molded body  100  in the periphery of the second framework right part  201  and the second framework left part  202  can become non-uniform easily, the foamed resin molded body  100  is also deformed easily. Particularly, as illustrated in  FIG. 15(B) , the compression stress and the tensile stress easily act non-uniformly as the thermal stress on the extension  182  in which the frame member  200  is not embedded, and the extension  182  is deformed easily so as to curved upward from the center. Moreover, since the contraction amount of the foamed resin molded body  100  after the molding is large in the longitudinal direction of the outer shape  400  of the vehicle seat member  1 , the second framework right part  201  and the second framework left part  202  extending in the direction crossing the longitudinal direction are particularly susceptible to the influence of the contraction of the foamed resin molded body  100  in the longitudinal direction after the molding. This problem can occur when the outer shape  400  of the vehicle seat member  1  has a shape (a rectangle, for example) having the transverse direction and the longitudinal direction and the second framework right part  201  and the second framework left part  202  extend in the direction crossing the longitudinal direction. 
     Thus, in this embodiment, on the section (see  FIG. 5 ) perpendicular to the extending direction of the second framework right part  201 , the gaps  101 ,  101  are formed between the second framework right part  201  and the part  112  of the foamed resin molded body  100  located on the outer side of the second framework right part  201 , and on the section perpendicular to the extending direction of the second framework left part  202 , the gaps  102 ,  102  are formed between the second framework left part  202  and the part of the foamed resin molded body  100  located on the outer side of the second framework left part  202 . In this embodiment, as illustrated in  FIG. 5 , the gaps  101 ,  101  are formed between an entire part  111  of the foamed resin molded body  100  surrounding the periphery of the second framework right part  201  on the section and the second framework right part  201  (that is, the gaps  101 ,  101  are formed on the entire periphery of the second framework right part  201  on the section), but in order to relax the influence of the contraction of the foamed resin molded body  100  in the direction (longitudinal direction) where the second framework right part  201  and the second framework left part  202  are opposed with each other, the gaps  101 ,  101  only need to be at least formed between the second framework right part  201  and the part  112  closer to the outer side than the second framework right part  201 . Moreover, by forming the gaps  101 ,  101  between the second framework right part  201  and the part  113  closer to the inner side than the second framework right part  201 , the influence of the expansion in the direction (longitudinal direction) where the second framework right part  201  and the second framework left part  202  are opposed with each other can be relaxed. However, as illustrated, on the section, formation of the gaps  101 ,  101  between the entire part  111  surrounding the second framework right part  201  and the second framework right part  201  in the foamed resin molded body  100  is further preferable since a direct influence by the contraction and expansion of the foamed resin molded body  100  in all the directions on the second framework right part  201  can be relaxed. The gaps  101 ,  101  are formed between the second framework right part  201  and the front part  120  as well as the rear part  130  of the foamed resin molded body  100 . The gaps  102 ,  102  in the periphery of the second framework left part  202  are also formed similarly. 
     In this embodiment, as illustrated in  FIG. 5 , the second framework right part  201  is disposed in the vicinity of the bottom surface  140  which is one of end surfaces of the foamed resin molded body  100  in the thickness direction. In the foamed resin molded body  100 , the part  111  surrounding the second framework right part  201  on the section has a groove with a bottom extending along the second framework right part  201 , opened to the bottom surface  140 , and formed in the foamed resin molded body  100  so as to contain the second framework right part  201  and has the gap  101  formed as an internal space of the groove. In this embodiment, since the gap  101  is formed only in the vicinity of the bottom surface  140  which is one of the end surfaces of the foamed resin molded body  100  in the thickness direction, mechanical strength of the entire foamed resin molded body  100  is not damaged, and the vehicle seat member  1  with high mechanical strength is obtained. 
     As the gap forming step of the method of this embodiment, when the gaps  101 ,  101 ,  102 ,  102  are formed in molding of the foamed resin molded body  100 , in-mold foam molding using a molding die including projecting portions corresponding to the gaps  101 ,  101 ,  102 ,  102  can be performed. 
       FIG. 7  illustrate an example of a method of forming the gap  101  between the part  111  of the foamed resin molded body  100  surrounding the entire periphery of the second framework right part  201  and the second framework right part  201  on the section perpendicular to the extending direction of the second framework right part  201  of the foamed resin molded body  100  during the molding of the foamed resin molded body  100 . In this method, a molding die  70  combining a separable first die  71  and second die  72  is used. In the molding die  70 , when the first die  71  and the second die  72  are clamped, a cavity  75  according to the foamed resin molded body  100  is formed in the molding die  70 . In the second die  72 , a projecting portion  73  corresponding to the gap  101  is formed. In the projecting portion  73 , a groove  74  opened into the molding die is formed. The groove  74  is constituted so as to accommodate the second framework right part  201  of the frame member  200  in its deepest part. 
     In the placing step of this embodiment, as illustrated in  FIG. 7(A) , first, the frame member  200  is placed in the molding die  70  so that each framework such as the second framework right part  201  is located in the cavity  75  of the molding die  70 . Then, after the first die  71  and the second die  72  in which the frame member  200  is placed in the cavity  75  are temporally clamped (cracking), pre-expanded resin particles  170  obtained by pre-expanding the expandable resin particles containing the resin and the foaming agent are filled and clamped. At this time, in order to prevent entry of the pre-expanded resin particles  170  into the groove  74 , it is necessary that an opening width of the groove  74  is formed having a width smaller than a dimension of the pre-expanded resin particles  170  or that after the second framework right part  201  of the frame member  200  is accommodated in the groove  74 , an appropriate measure is taken so that the pre-expanded resin particles  170  cannot enter into the groove  74  and then, the pre-expanded resin particles  170  are filled. 
     In this embodiment, in the in-mold foam molding, the entirety excluding the distal end parts  211 ,  211  of the front locking portions  210 ,  210  and the distal end part  221  of the rear locking portion  220  in the frame member  200  is disposed so as to be located inside the cavity  75  of the molding die  70 . The distal end parts  211 ,  211  of the front locking portions  210 ,  210  and the distal end part  221  of the rear locking portion  220  in the frame member  200  are disposed so as to be on the outer side of the cavity  75  of the molding die  70  or if they are to be disposed inside the cavity  75  of the molding die  70 , they are disposed by taking an appropriate measure so that the pre-expanded resin particles  170  do not enter the periphery thereof. 
     Subsequently, as illustrated in  FIG. 7(B) , the pre-expanded resin particles  170  are secondarily foamed by heating the inside of the cavity  75  of the molding die  70  by steam or the like, gaps among the pre-expanded resin particles  170  are filled, and the pre-expanded resin particles  170  are integrated by fusing them to each other so that the foamed resin molded body  100  is formed. At this time, the gaps  101 ,  101  corresponding to the projecting portions  73  of the molding die  70  are formed in the periphery on the section of the second framework right part  201 . 
     Subsequently, the molding die  70  is removed, and the vehicle seat member  1  of this embodiment in which the foamed resin molded body  100  and the frame member  200  are integrated is obtained. At this time, the foamed resin molded body  100  contracts at the time of the die removal or after the die removal. In  FIG. 7(C) , a position of the second framework right part  201  in a state accommodated in the groove  74  of the projecting portion  73  before the die removal of the molding die  70  is indicated by a dotted line. The foamed resin molded body  100  has a large contraction amount in the longitudinal direction of the outer shape  400  of the vehicle seat member  1  and thus, as indicated by an arrow in  FIG. 7(C) , the foamed resin molded body  100 ) in the periphery of the second framework right part  201  is moved inward by the die removal and the contraction, and in association with that, the second framework right part  201  is moved relatively outward in the gaps  101 ,  101 . As described above, by providing the gaps  101 ,  101 , a direct influence on the second framework right part  201  by the contraction of the foamed resin molded body  100  after the molding can be avoided. In  FIG. 7(C) , for the purpose of description, a relative position of the second framework right part  201  in the gaps  101 ,  101  after the contraction is indicated closer to the outer side with highlight, but in actuality, a movement distance to the outer side is slight, and as illustrated in  FIG. 5 , the position of the second framework right part  201  in the gaps  101 ,  101  can be regarded as substantially at the center. That is,  FIG. 5  and  FIG. 7(C)  illustrate the same section. 
     The other gaps  102 ,  102  can be also formed in molding of the foamed resin molded body  100  similarly to the gaps  101 ,  101 . 
     In this embodiment, the method of forming the gaps  101 ,  101 ,  102 ,  102  after the molding of the foamed resin molded body  100  is not particularly limited and the gaps  101 ,  101 ,  102 ,  102  can be formed by treating the foamed resin molded body  100  after the molding by using a hot wire or a blade for example. The formation of the gaps  101 ,  101 ,  102 ,  102  after the molding of the foamed resin molded body  100  is preferably performed while large contraction does not occur in the foamed resin molded body  100  after the foamed resin molded body  100  is in-mold molded and the die is removed, particularly it is preferably performed without delay during the amount of contraction of the resin is still within the range of elastic deformation of the material (such as metals) constituting the first framework  250 , the second framework  260 , the front locking portions  210 ,  210 , the rear locking portion  220 , or other portions of the frame member  200 , and more specifically, it is preferably performed within 60 minutes after the molding of the foamed resin molded body  100 . 
     First Invention/Second Embodiment 
     With regard to a second embodiment of the vehicle seat member  1  and the method of manufacturing the same of the first invention, features different from the aforementioned first embodiment will be described below on the basis of  FIGS. 8 to 11 . Description on features of the second embodiment in common with the first embodiment will be omitted. 
     In the second embodiment, the outer shape  400  of the vehicle seat member  1  has a shape having a short side direction and a longitudinal direction (a rectangle) and the extending directions of the first framework  250  and the second framework rear part  204  are both directions along the longitudinal direction. Then, a gap  105  along the extending direction of the first framework  250  is formed between a part of the first framework  250  and a part of the foamed resin molded body  100  located closer to an outer side and an inner side of the vehicle seat member  1  than the part in plan view, and gaps  106 ,  106  along the extending direction of the second framework rear part  204  are formed between a part of the second framework rear part  204  and a part of the foamed resin molded body  100  located closer to the outer side and the inner side of the vehicle seat member  1  than the part in plan view. In this embodiment, on the section (see  FIG. 9 ) perpendicular to the extending direction of the first framework  250 , the gap  105  along the extending direction of the first framework  250  is formed between a part  115  of the foamed resin molded body  100  surrounding the entire periphery of the first framework  250  and the first framework  250 . Similarly, on the section (see  FIG. 10 ) perpendicular to the extending direction of the second framework rear part  204 , the gaps  106 ,  106  along the extending direction of the second framework rear part  204  are formed between a part  116  of the foamed resin molded body  100  surrounding the entire periphery of the second framework rear part  204  and the second framework rear part  204 . 
     If the first framework  250  extending in the longitudinal direction of the outer shape  400  of the vehicle seat member  1  and the entire second framework rear part  204  are in close contact with the foamed resin molded body  100 , the following problem can occur.  FIG. 11(B)  is a sectional view of a part corresponding to a region X illustrated in  FIG. 8  when the gap  106  is not provided in the vehicle seat member  1  of the second embodiment at a height passing through the second framework rear part  204 . Displacement by contraction or expansion after molding of the foamed resin molded body  100  is larger in the longitudinal direction of the outer shape  400  indicated by an arrow in a lateral direction than in the short side direction of the outer shape  400  indicated by an arrow in a vertical direction in  FIG. 11(B) . Thus, as in  FIG. 11(B) , if the gap  106  is not provided in the vehicle seat member  1  of the second embodiment, and the entire second framework rear part  204  is in close contact with the foamed resin molded body  100 , a shearing force by the large contraction in the longitudinal direction of the foamed resin molded body  100  acts on the second framework rear part  204 , and deformation of the second framework rear part  204  and the foamed resin molded body  100  can occur. Moreover, when the foamed resin molded body  100  is expanded or contracted at a heat input into the manufactured vehicle seat member  1  or at the heat release after the heat input, deformation of the second framework rear part  204  and the foamed resin molded body  100  can occur similarly. There is a similar concern for the first framework  250  extending in the longitudinal direction of the outer shape  400 . 
     Thus, in the second embodiment, on the section perpendicular to the extending direction of the first framework  250 , the gap  105  is formed between the part  115  of the foamed resin molded body  100  surrounding the entire periphery of the first framework  250  and the first framework  250 , and on the section perpendicular to the extending direction of the second framework rear part  204 , the gap  106  is formed between the part  116  of the foamed resin molded body  100  surrounding the entire periphery of the second framework rear part  204  and the second framework rear part  204 . By means of this constitution, a direct influence of the contraction or expansion along the short side direction and the longitudinal direction of the outer shape  400  of the foamed resin molded body  100  on the first framework  250  and the second framework rear part  204  can be avoided.  FIG. 11(A)  illustrates a sectional view of the part of the region X illustrated in  FIG. 8  of the vehicle seat member  1  according to the second embodiment of the first invention at the height passing through the second framework rear part  204 . 
     In this embodiment, too, as illustrated in  FIGS. 9 and 10 , the first framework  250  and the second framework rear part  204  are disposed in the vicinity of the bottom surface  140  which is one of the end surfaces of the foamed resin molded body  100  in the thickness direction, respectively. In the foamed resin molded body  100 , the part  115  surrounding the first framework  250  and the part  116  surrounding the second framework rear part  204  have grooves with bottoms formed extending along the first framework  250  and the second framework rear part  204 , opened to the bottom surface  140  and, formed in the foamed resin molded body  100  so as to contain the first framework  250  and the second framework rear part  204  and have the gaps  105 ,  106  formed as internal spaces of the grooves, respectively. In this embodiment, since the gaps  105 ,  106  are formed only in the vicinity of the bottom surface  140  which is one of the end surfaces of the foamed resin molded body  100  in the thickness direction, mechanical strength of the entire foamed resin molded body  100  is not damaged, and the vehicle seat member  1  with high mechanical strength is obtained. 
     The forming method of the gaps  105 ,  106 ,  106  in the second embodiment is similar to the forming method of the gaps  101 ,  101 ,  102 ,  102  in the first embodiment. 
     First Invention/Third Embodiment 
     With regard to a third embodiment of the vehicle seat member  1  and the method of manufacturing the same of the first invention, features different from the aforementioned third embodiment will be described below on the basis of  FIGS. 12 to 14 . Description on features of the third embodiment in common with the first embodiment will be omitted. 
     In the third embodiment, a gap  108 , a gap  109 , a gap  110 , and a gap  111  are formed between the second framework first corner part  205  (hereinafter, referred to as the “first corner part  205 ” in some cases), the second framework second corner part  206  (hereinafter, referred to as the “second corner part  206 ” in some cases), the second framework third corner part  207  (hereinafter, referred to as the “third corner part  207 ” in some cases), and the second framework fourth corner part  208  (hereinafter, referred to as the “fourth corner part  208 ” in some cases) of the frame member  200 , and a part of the foamed resin molded body  100  in the peripheries thereof, respectively. 
     Since the foamed resin molded body  100  of the vehicle seat member  1  having a rectangular (substantially rectangular) outer shape  400  in plan view as illustrated is contracted or expanded along a direction of each side after molding, though a force is applied in any direction to the first to fourth corner parts  205  to  208  of the frame member  200  extending along the first corner  405 , the second corner  406 , the third corner  407 , and the fourth corner  408  of the outer shape  400  of the vehicle seat member  1 , the first to fourth corner parts  205  to  208  are connected to each other and relative positions are fixed, and thus, the frame member  200  is deformed easily. Moreover, in the vicinity of each of the first to fourth corner parts  205  to  208 , contraction of the foamed resin molded body  100  becomes non-uniform, and the foamed resin molded body  100  is also deformed easily. Moreover, when the foamed resin molded body  100  is expanded or contracted at a heat input into the manufactured vehicle seat member  1  or a heat release after the heat input, deformation of the frame member  200  and the foamed resin molded body  100  can occur similarly. 
     Thus, as in this embodiment, gaps are formed between each of two or more of the first to fourth corner parts  205  to  208  of the frame member  200  connected to each other and a part of the foamed resin molded body  100  located closer to the outer side and/or the inner side than the each of the two or more of the first to fourth corner parts  205  to  208 , wherein the gaps extend along the extending direction of each of the two or more of the first to fourth corner parts  205  to  208 , and wherein the two or more of the first to fourth corner parts  205  to  208  extend along each of two or more corners selected from the four corners  405  to  408  of the outer shape  400  of the vehicle seat member  1 , and wherein the two or more corners are selected so as to constitute one or more pairs of corners opposed in a direction of any one side of the outer shape  400  (in other words, the two or more corners are any one of a combination of the first corner  405  and the second corner  406 , a combination of the first corner  405 , the second corner  406 , and the third corner  407 , a combination of the first corner  405 , the second corner  406 , the third corner  307 , and the fourth corner  408 , a combination of the second corner  406  and the third corner  407 , a combination of the second corner  406 , the third corner  407 , and the fourth corner  408 , a combination of the third corner  407  and the fourth corner  408 , a combination of the third corner  407 , the fourth corner  408 , and the first corner  405 , a combination of the fourth corner  408  and the first corner  405 , and a combination of the fourth corner  408 , the first corner  405 , and the second corner  406 ). The gaps formed can reduce an influence on the frame member  200  caused by contraction or expansion of the vehicle seat member  1  along one or more sides of the outer shape  400 . 
     In the following description of the third embodiment, features of the gap  110  formed between the third corner part  207  and the foamed resin molded body  100  will be described, but the other gaps  108 ,  109 ,  111  also have the similar features. 
     As in the embodiment illustrated in  FIG. 13 , forming the gap  110  between the part of the foamed resin molded body  100  surrounding the entire periphery of the third corner part  207  and the third corner part  207  on the section perpendicular to the third corner part  207  is preferable, since the gap  110  reduces an influence of the force in various directions on the third corner part  207  by contraction or expansion of the foamed resin molded body  100  after the molding. However, not limited to this example, the gap  110  may have at least a structure formed between the part of the foamed resin molded body  100  located on the outer side and/or the inner side of the third corner part  207  and the third corner part  207  on the section perpendicular to the extending direction of the third corner part  207 . 
     In this embodiment, as illustrated in  FIG. 13 , the gap  110  is formed as a cylindrical hole surrounded by the foamed resin molded body  100  on the entire periphery on the section perpendicular to the extending direction of the third corner part  207  of the frame member  200 , and since mechanical strength of the entire foamed resin molded body  100  is not damaged, the vehicle seat member  1  with high mechanical strength is obtained. 
     In the third embodiment, the vehicle seat member  1  further includes a tubular body  500  embedded in the foamed resin molded body  100  in a state where the first corner part  205 , the second corner part  206 , the third corner part  207 , and the fourth corner part  208  of the frame member  200  are inserted therein, respectively. The gaps  108 ,  109 ,  110 ,  111  are formed between the first corner part  205 , the second corner part  206 , the third corner part  207 , and the fourth corner part  208  of the frame member  200 , and an inner peripheral surface  501  of the tubular body  500 . An outer peripheral surface  502  of the tubular body  500  is in contact with the foamed resin molded body  100 . 
     An example of the method of manufacturing the vehicle seat member  1  of the third embodiment will be described by referring to  FIG. 14 . Each of  FIG. 14  is a view corresponding to the V-V line arrow-view sectional view in  FIG. 12  and illustrates a step of forming the gap  110  in the periphery of the third corner part  207  of the frame member  200 . Since the gaps  108 ,  109 ,  111  in the peripheries of the first corner part  205 , the second corner part  206 , and the fourth corner part  208  of the frame member  200  can be also manufactured by the similar procedure, the description will be omitted. 
     As a placing step, first, as illustrated in  FIG. 14(A) , the frame member  200  and the tubular body  500  are disposed in a cavity  81  inside a molding die  80  in a state where the third corner part  207  of the frame member  200  is inserted through the tubular body  500  so that the gap  110  is formed between the third corner part  207  of the frame member  200  and the inner peripheral surface  501  of the tubular body  500 ). Further, after the molding die  80  in which the frame member  200  is disposed in the cavity  81  is temporarily clamped (cracking), pre-expanded resin particles  170  obtained by pre-expanding expandable resin particles containing a resin and a foaming agent are filled and clamped. At this time, in order to prevent entry of the pre-expanded resin particles  170  into the gap  110 , it is only necessary that an opening width of the gap  110  is formed having a width smaller than a dimension of the pre-expanded resin particle  170  or that after the frame member  200  and the tubular body  500  are installed in the molding die  80 , an appropriate measure is taken so that the pre-expanded resin particles  170  cannot enter into the gap  110  and then, the pre-expanded resin particles  170  are filled. 
     Subsequently, as illustrated in  FIG. 14(B) , the pre-expanded resin particles  170  are secondarily foamed by heating the inside of the cavity  81  of the molding die  80  by steam or the like, the gaps among the pre-expanded resin particles  170  are filled, and the pre-expanded resin particles  170  are integrated by fusing them to each other so that the foamed resin molded body  100  is formed. At this time, the foamed resin molded body  100  is brought into close contact with the outer peripheral surface  502  of the tubular body  50 X), but the inside of the tubular body  500  is held as the gap  110 . 
     Subsequently, the molding die  80  is removed, and the vehicle seat member  1  of the third embodiment in which the foamed resin molded body  100 , the frame member  200 , and the tubular body  500  are integrated. At this time, the foamed resin molded body  100  contracts at the time of the die removal or after the die removal. With regard to the foamed resin molded body  100 , as indicated by an arrow in  FIG. 14(C) , the foamed resin molded body  1000  in the periphery of the third corner part  207  is moved inward, and the third corner part  207  is moved relatively outward in the gap  110  with that. In  FIG. 14(C) , the position of the third corner part  207  in the gap  110  in the molding die  80  before the die removal is indicated by a dotted line. By providing the gap  110  as above, the direct influence on the third corner part  207  by the contraction of the foamed resin molded body  100  after the molding can be avoided. In  FIG. 14(C) , the relative position of the third corner part  207  in the gap  110  after the contraction is indicated with highlight for explanation, but in actuality, a movement distance to the outer side is slight, and as illustrated in  FIG. 13 , the position of the third corner part  207  in the gap  110  can be regarded as substantially at the center. That is,  FIG. 13  and  FIG. 14(C)  illustrate the same section. 
     When the vehicle seat member  1  of the third embodiment is manufactured by the aforementioned procedure, there is no need to provide the projecting portions according to the gaps  108 ,  109 ,  110 ,  111  in the molding die  80 , and the gap can be formed at a desired position by adjusting disposed positions and the number of the tubular bodies  500 , which is preferable. 
     The tubular body  500  only needs to be able to hold the internal space under the condition of molding the foamed resin molded body  100 , and the material of the tubular body  500  is not particularly limited. 
     First Invention/Other Embodiments 
     The vehicle seat member of the first invention and the method of manufacturing the same are not limited to the aforementioned first to third embodiments, but various changes can be made within a range not departing from the gist of the first invention described in the claims. 
     For example, in the vehicle seat member  1  in the first embodiment, the gap  105  described in the second embodiment may be further formed between a part of the first framework  250  and the foamed resin molded body  100 , the gaps  106 ,  106  described in the second embodiment may be formed between a part of the second framework rear part  204  and the foamed resin molded body  100 , the gap  108  described in the third embodiment may be formed between the first corner part  205  of the second framework  260  and the foamed resin molded body  100 , the gap  109  described in the third embodiment may be formed between the second corner part  206  of the second framework  260  and the foamed resin molded body  100 , the gap  110  described in the third embodiment may be formed between the third corner part  207  of the second framework  260  and the foamed resin molded body  100 , and the gap  111  described in the third embodiment may be formed between the fourth corner part  208  of the second framework  260  and the foamed resin molded body  100 . 
     Moreover, in the vehicle seat member  1  of the first embodiment and/or the second embodiment, one or more of the gaps  101 ,  101 ,  102 ,  102 ,  105 ,  106 ,  106  may be formed as internal spaces of the tubular body  500  disposed so that parts of the first framework  250  and the second framework  260  are inserted as described in the third embodiment. 
     &lt;Second Invention&gt; 
     Hereinafter, a vehicle seat member according to the second invention and embodiments of a vehicle seat will be described by referring to the drawings. However, a range of the second invention is not limited to individual embodiments. 
     Second Invention/First Embodiment 
     2-1-1. Vehicle Seat Member  2010   
     A first embodiment of a vehicle seat member and a method of manufacturing the same will be described on the basis of  FIGS. 16 to 20 . 
     As illustrated in  FIGS. 16 and 17 , the vehicle seat member  2010  includes a frame member  2020  and a foamed resin molded body  2030  in which at least a part of the frame member  2020  is embedded as a basic constitution. 
     An entire shape of the vehicle seat member  2010  is not particularly limited but as illustrated in  FIG. 19 , a rectangular shape in plan view is common. In the description, a rectangle refers to a square such as a rectangle, a regular square, and the like, and not only the rectangle or the regular square, it may be a shape such as a trapezoid or a parallelogram. In the description, the rectangle also includes a substantial rectangle, and corner parts may be rounded or a part or the whole of a side constituting the rectangle may be a bent side, for example. 
     In this embodiment, as illustrated in  FIG. 19 , an outer shape  2 S of the vehicle seat member  2010  in plan view is a rectangle having a short side and a long side and has a shape having a short side direction and the longitudinal direction. The outer shape  2 S includes a right edge  2   s R and a left edge  2   s L constituting the short sides, a front edge  2   s F and a rear edge  2   s B constituting the long sides as four sides, and corners  2   s C constituting four corners. The terms front, rear, left, and right in this embodiment refer to directions when an advancing (front) direction of the vehicle is seen from the vehicle in a state where an occupant is seated in the vehicle. 
     The vehicle seat member  2010  of this embodiment may be made into a vehicle seat  2001  by laminating/disposing an upper seat member  2050  such as a cushion material or the like as appropriate from a side of an upper surface  2011  of the vehicle seat member  2010 , in other words, an upper surface  2031  of the foamed resin molded body  2030  as illustrated in  FIG. 18 , for example. Moreover, the vehicle seat member  2010  may be covered by an appropriate exterior material together with the cushion material or the like so as to have the vehicle seat  2001 . 
     2-1-2. Frame Member  2020   
     As illustrated in  FIGS. 16 and 17 , the frame member  2020  is embedded in order to apply required shape retaining properties and strength to the foamed resin molded body  2030 . The frame member  2020  is usually constituted by a material whose dimensions are not substantially changed as compared to the foamed resin molded body  2030  under a condition that the foamed resin molded body  2030  is molded or a metal material such as steel or aluminum, for example. 
     The frame member  2020  includes a linear framework  2022  extending inside the foamed resin molded body  2030 , a first locking fixture  2024 A, a second locking fixture  2024 B, a third locking fixture  2024 C fixed to different positions in the extending direction in which the framework  2022  extends, a first plate-shaped member  2023 A connecting the first locking fixture  2024 A and the framework  2022 , and a second plate-shaped member  2023 B connecting the second locking fixture  2024 B and the framework  2022  along the outer shape  2 S of the vehicle seat member  2010  in plan view. 
     The framework  2022  includes a framework first section  2022 - 1  extending along the front edge  2   s F of the outer shape  2 S and a framework second section  2022 - 2  extending along the right edge  2   s R, the rear edge  2   s B, and the left edge  2   s L of the outer shape  2 S as sections sandwiched by the first locking fixture  2024 A and the second locking fixture  2024 B. 
     The framework first section  2022 - 1  in the framework  2022  is separated into a first part  2201  extending such that the first locking fixture  2024 A is fixed to a side of one end  2201   a  and another end  2201   b  is located between the first locking fixture  2024 A and the second locking fixture  2024 B and a second part  2202  extending such that the second locking fixture  2024 B is fixed to a side of one end  2202   a  and another end  2202   b  is located between the first locking fixture  2024 A and the second locking fixture  2024 B. In the framework  2022 , a side of the other end  2201   b  of the first part  2201  in the framework first section  2022 - 1  is not connected to a side of the other end  2202   b  of the second part  2202 . The first part  2201  and the second part  2202  of the framework first section  2022 - 1  both extend in a direction connecting the first locking fixture  2024 A and the second locking fixture  2024 B, and this direction is called an “extending direction” in the second invention in some cases. 
     In this embodiment, the other end  2201   b  of the first part  2201  in the framework first section  2022 - 1  of the framework  2022  is located at a position closer to the first locking fixture  2024 A than the other end  2202   b  of the second part  2202 . In other words, a gap  2203  is formed between the other end  2201   b  of the first part  2201  in the framework first section  2022 - 1  of the framework  2022  and the other end  2202   b  of the second part  2202 , and in the extending direction, the first part  2201  is closer to a side of the first locking fixture  2024 A than the gap  2203 , while the second part  2202  is closer to a side of the second locking fixture  2024 B than the gap  2203 . 
     The first part  2201  and the second part  2202  in the framework first section  2022 - 1  of the framework  2022  extends along a part of the center of the front edge  2   s F in its vicinity and is embedded in a spot slightly on an inner side of the part of the outer peripheral surface  2033  of the foamed resin molded body  2030  forming the front edge  2   s F. 
     The framework first section  2022 - 1  of the framework  2022  is a part along the longitudinal direction of the outer shape  2 S of the vehicle seat member  2010  and is called a “longitudinal part” of the framework  2022  in the second invention in some cases. 
     The framework second section  2022 - 2  in the framework  2022  extends along the right edge  2   s R, the rear edge  2   s B, and the left edge  2   s L of the outer shape  2 S in their vicinities and is embedded in a spot slightly on the inner side of the part of the outer peripheral surface  2033  of the foamed resin molded body  2030  forming the right edge  2   s R, the rear edge  2   s B, and the left edge  2   s L. 
     The framework second section  2022 - 2  in the framework  2022  has the first locking fixture  2024 A fixed to the side of the one end  2022 - 2   a  and the second locking fixture  2024 B fixed to the side of the other end  2022 - 2   b . The framework second section  2022 - 2  has a structure in which opposed parts  2022 - 2   c ,  2022 - 2   c  opposed to each other across a space inside a rim part  2035  are connected through a connecting part  2022 - 2   d.    
     In this embodiment, the first locking fixture  2024 A and the second locking fixture  2024 B are not linked to each other in the framework first section  2022 - 1  of the framework  2022  but are linked with each other through another section (the framework second section  2022 - 2 ), whereby the frame member  2020  is integrally molded in general. The integrally molded frame member  2020  is preferable since an operation of disposition in the molding die is easy. 
     The framework  2022  and the first locking fixture  2024 A are connected through the first plate-shaped member  2023 A. Specifically, the first plate-shaped member  2023 A is fixed to the side of the one end  2201   a  of the first part  2201  in the framework first section  2022 - 1  and the side of the one end  2022 - 2   a  in the framework second section  2022 - 2  in the framework  2022 . The first locking fixture  2024 A is fixed to the first plate-shaped member  2023 A. 
     The framework  2022  and the second locking fixture  2024 B are connected through the second plate-shaped member  2023 B. Specifically, the second plate-shaped member  2023 B is fixed to the side of the one end  2202   a  of the second part  2202  in the framework first section  2022 - 1  and the side of the other end  2022 - 2   b  in the framework second section  2022 - 2  in the framework  2022 . The second locking fixture  2024 B is fixed to the second plate-shaped member  2023 B. 
     As described above, by means of the framework first section  2022 - 1  and the framework second section  2022 - 2  of the framework  2022  as well as the first plate-shaped member  2023 A and the second plate-shaped member  2023 B connecting them, the frame member  2020  circles around the entirety along the outer shape  2 S of the vehicle seat member  2010  except a section between the first part  2201  and the second part  2202  in the framework first section  2022 - 1  of the framework  2022 . In this embodiment, the frame member  2020  circles around the entirety along the outer shape  2 S of the vehicle seat member  2010 , but the frame member  2020  may circle around intermittently along the outer shape  2 S of the vehicle seat member  2010 , for example. In other words, not limited to this form, the framework may be disposed only on a part of a part along the outer shape  2 S. For example, the framework  2022  may be disposed only along the front edge  2   s F. 
     The first locking fixture  2024 A, the second locking fixture  2024 B, and the third locking fixture  2024 C are parts by which the vehicle seat member  2010  is locked on the vehicle. The first locking fixture  2024 A and the second locking fixture  2024 B are disposed in the vicinity of both ends of the front edge  2   s F of the vehicle seat member  2010  and a part thereof protrudes to the outside of the foamed resin molded body  2030  below the vehicle seat member  2010 . The first locking fixture  2024 A includes a base  2241 A embedded in the foamed resin molded body  2030  and fixed to the first plate-shaped member  2023 A, a column portion  2242 A linked with the base  2241 A and extending toward the outside of the foamed resin molded body  2030 , and a locking portion  2243 A extending from the column portion  2242 A and protruding to the outside of the foamed resin molded body  2030 . Similarly, the second locking fixture  2024 B includes a base  2241 B embedded in the foamed resin molded body  2030  and fixed to the second plate-shaped member  2023 B, a column portion  2242 B linked with the base  2241 B and extending toward the outside of the foamed resin molded body  2030 , and a locking portion  2243 B extending from the column portion  2242 B and protruding to the outside of the foamed resin molded body  2030 . The locking portions  2243 A,  2243 B are curved in a form of a substantial U-shape and are exposed from the foamed resin molded body  2030 . 
     Moreover, the third locking fixture  2024 C is directly fixed to the center of the connecting part  2022 - 2   d  along the rear edge  2   s B in the framework second section  2022 - 2  of the second framework  2022  and protrudes rearward. The base  2241 C of the third locking fixture  2024 C is embedded in the foamed resin molded body  2030  and is fixed to the connecting part  2022 - 2   d . A locking portion  2242 C at a distal end is curved in form of a substantial U-shape, is exposed from the foamed resin molded body  2030 , and is used for engagement with the vehicle. 
     In this embodiment, the locking portion  2243 A of the first locking fixture  2024 A, the locking portion  2243 B of the second locking fixture  2024 B, and the locking portion  2242 C of the third locking fixture  2024 C are formed by bending a wire rod into a substantial U-shape, respectively, but this structure is not limiting but may have a structure capable of locking in accordance with the structure on the vehicle side. Moreover, a position of the third locking fixture  2024 C is not limited to the center of the connecting part  2022 - 2   d  in the framework second section  2022 - 2  of the second framework  2022 . 
     In this embodiment, the first locking fixture  2024 A and the second locking fixture  2024 B are fixed to the framework  2022  through the first plate-shaped member  2023 A and the second plate-shaped member  2023 B, respectively, but this form is not limiting, and as in the third locking fixture  2024 C, they may be directly fixed to the framework  2022  not through the plate-shaped member. Moreover, the number of the locking fixtures is not limited to three. 
     In this embodiment, each of the aforementioned parts of the framework  2022  as well as the first locking fixture  2024 A, the second locking fixture  2024 B, and the third locking fixture  2024 C can be constituted by a wire rod (wire) made of steel or aluminum having a diameter of approximately 3 to 6 mm or the like, for example. Moreover, each of the aforementioned parts of the framework  2022  as well as the first locking fixture  2024 A, the second locking fixture  2024 B, and the third locking fixture  2024 C may be a band-shaped or tubular steel material made of metal, for example. Moreover, the entire frame member  2020  may be manufactured by punch molding and press molding from a steel plate. In the second invention, the framework is “linear” is not limited to a wire rod such as a wire but may be the aforementioned band-shape, tubular, or the like, for example, and is not particularly limited as long as it extends along substantially one line. 
     2-1-3. Foamed Resin Molded Body  2030   
     As illustrated in  FIGS. 16 and 17 , the foamed resin molded body  2030  is an in-mold foamed resin molded body of a foamed resin. The foamed resin is not particularly limited, but a foamed thermoplastic resin is usually used, and a foamed polystyrene-based resin, a foamed composite resin containing a polystyrene-based resin and a polyolefin-based resin, a foamed polyolefin-based resin, and the like are suitably used, and the foamed polystyrene-based resin or the foamed composite resin containing the polystyrene-based resin and the polyolefin-based resin is particularly preferable. The foamed polystyrene-based resin or the foamed composite resin containing the polystyrene-based resin and the polyolefin-based resin has small degrees of thermal expansion and thermal contraction and thus, it is particularly preferable from a viewpoint that deformation of the foamed resin molded body and the frame member is suppressed. An expansion ratio can be adjusted as appropriate in accordance with a type of the foamed resin, but it is approximately 10 to 50 times in general or approximately 20 to 40 times typically. 
     On the foamed resin molded body  2030 , an upper surface  2031  on which an occupant of the vehicle is seated and a bottom surface  2032  which is on a side fastened to the vehicle are formed. The foamed resin molded body  2030  has the rim part  2035  in which the frame member  2020  is embedded and defining the outer shape  2 S of the vehicle seat member  2010  in plan view of the vehicle seat member  2010 . The rim part  2035  is constituted by a front part  2035   a  located on a front of a seat and a rear part  2035   b  formed integrally with the front part  2035   a  and inclined rearward in a state where the vehicle seat member  2010  is mounted. When the vehicle seat member  2010  is assembled in the vehicle, the front part  2035   a  of the foamed resin molded body  2030  supports a thigh part of the occupant and the rear part  2035   b  supports a buttock part of the occupant. 
     Specifically, as illustrated in  FIG. 18 , the upper surface  2031  of the foamed resin molded body  2030  is formed so as to hold the thigh part and the buttock part of the occupant through the upper seat member  2050  by being a curved surface dented downward so that a vicinity of the rear end of the front part  2035   a  becomes a deepest part in the illustrated embodiment. However, the shape and the thickness of the foamed resin molded body  2030  can be changed in various ways in accordance with a shape of the vehicle body side on which the vehicle seat member  2010  is mounted and is not limited to the illustrated embodiment. The upper surface  2031  of the foamed resin molded body  2030  may be substantially a flat shape, for example. 
     The foamed resin molded body  2030  includes an extension  2036  extending inward from the rim part  2035  so as to bridge the rim part  2035  inside of the rim part  2035 . More specifically, the extension  2036  has a first extension part  2036 A extending in the longitudinal direction and two second extension parts  2036 B extending in the short side direction. In this embodiment, the first extension part  2036 A is formed so as to extend between the opposed parts  2022 - 2   c ,  2022 - 2   c  in the framework second section  2022 - 2  of the framework  2022 . The first extension part  2036 A and the second extension part  2036 B are linked by a linking portion  2036 C. As described above, by providing the first extension part  2036 A and the second extension part  2036 B crossing each other inside the rim part  2035 , the vehicle seat member  2010  can be reinforced. 
     Moreover, by forming the extension  2036  in the space inside the rim part  2035 , hollow portions  2038   a ,  2038   b  are formed in the front part  2035   a  and the rear part  2035   b  of the foamed resin molded body  2030 , respectively. The hollow portions  2038   a ,  2038   b  are provided for the purpose of reducing a weight of the foamed resin molded body  2030  and of accommodating the other members constituting the vehicle seat (a cushion material, members of a console box, and the like, for example, which are elastically deformed more easily than the foamed resin molded body  2030 ). 
     However, the foamed resin molded body in the second invention is not limited to the illustrated form having the hollow portion formed and including the rim part and the extension. There may be a foamed resin molded body with no hollow portion formed, for example. 
     When a heat is input into the aforementioned vehicle seat member  2010  (or when the input heat is released), materials of the foamed resin of the foamed resin molded body  2030  and the frame member  2020  embedded in the foamed resin molded body  2030  which are materials of the vehicle seat member  2010  have different thermal expansion coefficients and thus, this difference in the thermal expansion coefficients can appear easily as a difference in the expansion amounts or the contraction amounts between (the rim part  2035  of) the foamed resin molded body  2030  and the frame member  2020 . 
     Particularly, since the first locking fixture  2024 A, the second locking fixture  2024 B, and the framework first section  2022 - 1  of the framework  2022  sandwiched by them include the parts extending in a plurality of directions, thermal contraction or thermal expansion does not occur uniformly in the foamed resin molded body  2030  in which these parts of the frame member  2020  are embedded. Thus, the frame member  2020  and/or the foamed resin molded body  2030  is deformed particularly easily in the vicinities of the first locking fixture  2024 A, the second locking fixture  2024 B, and the framework first section  2022 - 1  of the framework  2022  sandwiched by them. Particularly, such phenomenon is remarkable in the vicinity of the framework first section  2022 - 1  of the frameworks  2022  extending in the longitudinal direction. 
     Thus, in the second invention, the framework first section  2022 - 1  of the framework  2022  is separated to the first part  2201  and the second part  2202 . By means of this constitution, the first part  2201  and the second part  2202  can be relatively moved in the framework first section  2022 - 1  of the framework  2022 . Particularly when the first locking fixture  2024 A and the second locking fixture  2024 B are linked with each other through another section (the framework second section  2022 - 2 ) of the framework  2022  as in this embodiment, the first part  2201  and the second part  2202  in the framework first section  2022 - 1  of the framework  2022  can be elastically deformed. Thus, under the condition that the difference is generated in the contraction amounts between the foamed resin molded body  2030  and the frame member  2020 , the difference in the contraction amounts between the foamed resin molded body  2030  and the frame member  2020  can be absorbed between a side of another end  2201   b  of the first part  2201  and a side of another end  2202   b  of the second part  2202 . As a result, deformation of the rim part  2035  in which the frame member  2020  is embedded can be suppressed. 
     Particularly, the extension  2036  (particularly, the first extension part  2036 A) in which the frame member  2020  is not disposed and constituted only by the foamed resin is deformed easily as being curved from the center thereof. However, even in such a case, by separating the framework first section  2022 - 1  of the framework  2022  into the first part  2201  and the second part  2202 , the entire shape of the vehicle seat member  2010  can be kept to a predetermined shape. 
     Moreover, in this embodiment, since the framework first section  2022 - 1  extending in the longitudinal direction of the framework  2022  is separated into the first part  2201  and the second part  2202 , a large difference in the contraction amounts in the longitudinal direction between the frame member  2020  and the foamed resin molded body  2030  can be absorbed. 
     2-2. Method of Manufacturing Vehicle Seat Member  2010   
     The method of manufacturing the vehicle seat member  2010  will be described below by referring to  FIGS. 20 and 21 . When the vehicle seat member  2010  of this embodiment is to be manufactured, the frame member  2020  is prepared. Subsequently, after the pre-expanded resin particles  2030 A obtained by pre-expanding the expandable resin particles containing the resin and the foaming agent are filled, steam is supplied into a molding die  2007  so as to foam the pre-expanded resin particles  2030 A, and the foamed resin molded body  2030  is molded. After that, the foamed resin molded body  2030  is removed from the molding die  2007  together with the frame member  2020  and cooled by heat releasing or the like. 
     The foamed resin molded body  2030  usually has a property of slightly contracting when remaining heat during foam molding is released after the molding. On the other hand, the frame member  2020  constituted by a material such as metal hardly contracts as compared to the foamed resin molded body  2030  before and after the molding of the foamed resin molded body  2030 . Therefore, as illustrated in  FIG. 21( a ) , after the foamed resin molded body  2030  is molded by the molding die  2007  made of a first die  2071  and a second die  2072 , for a period of time immediately after the molding until the foamed resin molded body  2030  is removed from the molding die  2007  and the foamed resin molded body  2030  releases heat, the foamed resin molded body  2030  is thermally contracted. 
     As a result, as illustrated in  FIG. 21( b ) , the rim part  2035  in which the framework first section  2022 - 1  sandwiched between the first locking fixture  2024 A and the second locking fixture  2024 B in the framework  2022  is embedded is deformed in some cases. Moreover, though not shown, both sides of the extension  2036  where the frame member  2020  is not present are restrained by the rim part  2035  where the frame member  2020  is present and thus, the compression stress and the tensile stress non-uniformly act as the thermal stress on the extension  2036 , and the extension  2036  is deformed easily so as to be curved upward from the center. A deformed state of the foamed resin molded body  2030  immediately after the molding is held even after the heat release. 
     In view of these points, in this embodiment, the vehicle seat member  2010  is manufactured as follows. First, the frame member  2020  having the aforementioned structure is prepared. Specifically, the frame member  2020  having the linear framework  2022  disposed along the outer shape  2 S as well as the first locking fixture  2024 A and the second locking fixture  2024 B fixed at the different positions in the extending direction of the framework  2022 , in which the first section  2022 - 1  which is one of the sections sandwiched by the first locking fixture  2024 A and the second locking fixture  2024 B in the framework  2022  is separated into the first part  2201  and the second part  2202  is prepared. 
     Subsequently, in plan view of the vehicle seat member  2010 , the frame member  2020  is disposed in the molding die  2007  so that the frame member  2020  extends along the outer shape  2 S of the vehicle seat member  2010  (placing step). In this placing step, the framework first section  2022 - 1  extends along the longitudinal direction of the outer shape  2 S of the vehicle seat member  2010 . 
     As illustrated in  FIG. 20( a ) , the molding die  2007  is made of the first die  2071  and the second die  2072 , and when the first die  2071  and the second die  2072  are clamped, a cavity  2073  according to the foamed resin molded body  2030  is formed in the molding die  2007 . 
     Subsequently, as illustrated in  FIG. 20( a ) , the first die  2071  and the second die  2072  in which the frame member  2020  is disposed is temporarily clamped (cracking) and then, the pre-expanded resin particles  2030 A obtained by pre-expanding the expandable resin particles containing the resin and the foaming agent are filled therein and clamped. 
     Subsequently, as illustrated in  FIG. 20( b ) , the pre-expanded resin particles  2030 A are secondarily foamed by heating the inside of the cavity  2073  of the molding die  2007  by steam or the like, the gaps among the pre-expanded resin particles  2030 A are filled, and the pre-expanded resin particles  2030 A are integrated by fusing them to each other so that the foamed resin molded body  2030  is molded (molding step). 
     As described above, in the molding die  2007 , the foamed resin molded body  2030  including the rim part  2035  and the extension  2036  can be molded. The molded rim part  2035  has the frame member  2020  embedded and forms the outer shape  2 S of the vehicle seat member  2010 . Moreover, the molded extension  2036  extends on the inner side from the rim part  2035  so as to bridge the rim part  2035  inside of the rim part  2035 . 
     Subsequently, as illustrated in  FIG. 20( c ) , the foamed resin molded body  2030  is removed from the molding die  2007 , and the foamed resin molded body  2030  heated by the heat during the molding is cooled (cooling step). Here, previously, as illustrated in  FIG. 21( b ) , the rim part  2035  of the foamed resin molded body  2030  and the framework first section  2022 - 1  of the frame member  2020  embedded therein were deformed by the thermal contraction so as to be curved upward and the extension  2036  was also deformed in some cases, for example. 
     However, in this embodiment, as illustrated in  FIG. 20( c ) , by separating the framework first section  2022 - 1  of the framework  2022  into the first part  2201  and the second part  2202 , the difference in the contraction amounts between the foamed resin molded body  2030  and the frame member  2020  can be absorbed between the side of the other end  2201   b  of the first part  2201  and the side of the other end  2202   b  of the second part  2202 . As a result, when the heat during the molding of the foamed resin molded body  2030  is released, deformation of the frame member  2020 , the rim part  2035 , and the extension  2036  caused by the thermal contraction can be suppressed, and the entire shape of the vehicle seat member  2010  can be kept to the predetermined shape. As a result, the vehicle seat member  2010  with high dimensional accuracy can be manufactured. 
     Particularly, when the frame member  2020  is made to continuously circle around along the outer shape  2 S of the vehicle seat member  2010 , such deformation occurs easily, but in this embodiment, even in such a case, by separating the framework first section  2022 - 1  of the framework  2022  into the first part  2201  and the second part  2202 , the deformation can be suppressed. 
     Second Invention/Second Embodiment 
     The vehicle seat member  2010  according to a second embodiment of the second invention and the method of manufacturing same will be described below by referring to  FIGS. 22 and 23 . The vehicle seat member  2010  according to the second embodiment is different from that of the first embodiment in structures of the first part  2201  and the second part  2202  of the framework first section  2022 - 1  of the framework  2022 . Therefore, the same constitutions as those in the first embodiment are given the same reference numerals and detailed description will be omitted. 
     In this embodiment, as illustrated in  FIGS. 22 and 23 , the other end  2201   b  of the first part  2201  is located at a position closer to the second locking fixture  2024 B than the other end  2202   b  of the second part  2202  in the extending direction of the framework first section  2022 - 1  of the framework  2022  of the frame member  2020 , and a side  2201   c  of the other end  2201   b  of the first part  2201  and a side  2202   c  of the other end  2202   b  of the second part  2202  are disposed so as to be juxtaposed in a direction perpendicular to the extending direction. 
     According to this constitution, since the first part  2201  and the second part  2202  of the framework first section  2022 - 1  of the framework  2022  are disposed without disconnection in the extending direction between the first locking fixture  2024 A and the second locking fixture  2024 B, in the vehicle seat member  2010  in which this frame member  2020  is embedded in the foamed resin molded body  2030 , sufficient mechanical strength is given to a part between the first locking fixture  2024 A and the second locking fixture  2024 B of the foamed resin molded body  2030 . 
     Moreover, in the first part  2201  and the second part  2202  of the framework first section  2022 - 1  of the framework  2022 , the side  2201   c  of the other end  2201   b  of the first part  2201  and the side  2202   c  of the other end  2202   b  of the second part  2202  are disposed side by side but since they are not linked with each other, the first part  2201  and the second part  2202  can be moved relatively. 
     Thus, according to the second embodiment, the difference in the contraction amounts between the foamed resin molded body  2030  and the frame member  2020  can be absorbed between the side  2201   c  of the other end  2201   b  of the first part  2201  and the side  2202   c  of the other end  2202   b  of the second part  2202 , while strength of the vehicle seat member  2010  to be manufactured is kept. 
     In the second embodiment, the side  2201   c  of the other end  2201   b  of the first part  2201  and the side  2202   c  of the other end  2202   b  of the second part  2202  in the framework first section  2022 - 1  of the framework  2022  do not have to be in contact with each other as illustrated but may be separated from each other. Moreover, if they are separated from each other, there may be a part of the foamed resin molded body  2030  between the side  2201   c  of the other end  2201   b  of the first part  2201  and the side  2202   c  of the other end  2202   b  of the second part  2202  in the framework first section  2022 - 1  of the framework  2022 . 
     Some embodiments of the second invention have been described in detail, but the second invention is not limited to the aforementioned embodiments but is capable of various design changes within a range not departing from the spirit of the second invention described in “Solution to Problem”. 
     &lt;Third Invention&gt; 
     Third Invention/First Embodiment 
     3-1. Vehicle Seat Member  3010   
     A first embodiment of a vehicle seat member and a method of manufacturing the same will be described on the basis of  FIGS. 24 to 29 . 
     As illustrated in  FIGS. 24 and 25 , the vehicle seat member  3010  includes a frame member  3020  and a foamed resin molded body  3030  in which at least a part of the frame member  3020  is embedded as a basic constitution. 
     An entire shape of the vehicle seat member  3010  is not particularly limited but as illustrated in  FIG. 27 , a rectangular shape in plan view is common. In the description, a rectangle refers to a square such as a rectangle, a regular square and the like, and not only the rectangle or the regular square, it may be a shape such as a trapezoid or a parallelogram. In the description, the rectangle also includes a substantial rectangle, and corner parts may be rounded or a part or the whole of a side constituting the rectangle may be a bent side, for example. 
     In this embodiment, as illustrated in  FIG. 27 , an outer shape  3 S of the vehicle seat member  3010  in plan view is a rectangle having a short side and a long side and has a shape having a short side direction and the longitudinal direction. The outer shape  3 S includes a right edge  3   s R and a left edge  3   s L constituting the short sides, a front edge  3   s F and a rear edge  3   s B constituting the long sides as four sides, and corners  3   s C constituting four corners. The terms front, rear, left, and right in this embodiment refer to directions when an advancing (front) direction of the vehicle is seen from the vehicle in a state where an occupant is seated in the vehicle. 
     The vehicle seat member  3010  of this embodiment may be made into a vehicle seat  3001  by laminating/disposing an upper seat member  3050  such as a cushion material or the like as appropriate from a side of an upper surface  3011  (upper surface  3031 ) of the vehicle seat member  3010  (foamed resin molded body  3030 ). Moreover, the vehicle seat member  3010  may be covered by an appropriate exterior material together with the cushion material or the like so as to have the vehicle seat  3001 . 
     3-2. Frame Member  3020   
     As illustrated in  FIGS. 24 to 27 , the frame member  3020  is embedded in order to apply required shape retaining properties and strength to the foamed resin molded body  3030 . 
     The frame member  3020  is usually constituted by a material whose dimensions are not substantially changed as compared to the foamed resin molded body  3030  under a condition that the foamed resin molded body  3030  is molded or a metal material such as steel or aluminum, for example. 
     The frame member  3020  includes first and second frameworks  3021 ,  3022  extending inside the foamed resin molded body  3030  and a pair of bases  3023 ,  3023  linked with end portions of the first and second frameworks  3021 ,  3022  along the outer shape  3 S of the vehicle seat member  301  in plan view. The second framework  3022  has a structure in which a pair of opposed parts  3022   a ,  3022   a  continue to each other, and in the description, the second framework  3022  is called a “continuous part” of the frame member  3020  in some cases. 
     The frame member  3020  further includes a front locking portion  3024  mounted on each of the bases  3023  and a rear locking portion  3025  mounted on the second framework  3022 . In this embodiment, as the first and second frameworks  3021 ,  3022  and the front and rear locking portions  3024 ,  3025 , a wire rod (wire) made of steel or aluminum having a diameter of approximately 3 to 6 mm or the like is used, for example, but it may be a band-shaped or tubular steel material made of metal, for example. Moreover, the frame member  3020  may be manufactured by punch molding and press molding from a steel plate. 
     The first framework  3021  of the frame member  3020  extends along a part of the center of the front edge  3   s F in the vicinity thereof, and the second framework  3022  extends along a part of both sides of the front edge  3   s F, the right edge  3   s R, the left edge  3   s L, the rear edge  3   s B, and each of the corners  3   s C in their vicinities. The frame member  3020  is embedded in a spot slightly on an inner side of an outer peripheral surface  3033  of the foamed resin molded body  3030  defining the outer shape  3 S so as to follow the outer shape  3 S of the vehicle seat member  3010 . 
     As described above, the first and second frameworks  3021 ,  3022  of the frame member  3020  continuously circle around along the outer shape  3 S of the vehicle seat member  3010  together with the pair of bases  3023 ,  3023  connecting them. In this embodiment, parts including the first and second frameworks  3021 ,  3022  of the frame member  3020  continuously circle around along the outer shape  3 S of the vehicle seat member  3010  but the first and second frameworks  3021 ,  3022  of the frame member  3020  may circle around intermittently along the outer shape  3 S of the vehicle seat member  3010 , for example. That is, not limited to this form, the framework may be disposed only on a part of a part along the outer shape  3 S. For example, it may be so constituted that the second framework  3022  is not linked with the bases  3023 ,  3023  but extends along the rear edge  3   s B. Moreover, the number of the frameworks constituting the frame member  3020  is not limited to two but the number may be one, or three or more. 
     The front locking portion  3024  and the rear locking portion  3025  constituting the frame member  3020  are parts by which the vehicle seat member  3010  is locked on the vehicle. The front locking portion  3024  is linked with the base  3023  by welding, bonding, or the like, for example, and protrudes downward from the base  3023 . A distal end part  3024   a  of the front locking portion  3024  is curved having a substantial U-shape and is exposed from the foamed resin molded body  3030 , and a base end part  3024   b  is embedded in the foamed resin molded body  3030  together with the base  3023 . More specifically, the base end part  3024   b  is embedded in the foamed resin molded body  3030  by the entire periphery thereof. As a result, even if a force in the pulling-out direction is applied when the vehicle seat member  3010  of this embodiment is locked on the vehicle through the distal end part  3024   a  of the front locking portion  3024 , the front locking portion  3024  is held by the foamed resin molded body  3030 , and resistance against the force in the pulling-out direction can be improved. 
     Moreover, the rear locking portion  3025  protrudes rearward from a center of a part  3022   b  along the rear edge  3   s B in the second framework  3022 . The distal end part  3025   a  of the rear locking portion  3025  is curved having a substantial U-shape and is exposed from the foamed resin molded body  3030 , and the base end part  3025   b  is embedded in the foamed resin molded body  3030 . 
     In this embodiment, the distal end parts  3024   a ,  3025   a  of the front locking portion  3024  and the rear locking portion  3025  are formed by bending a wire rod into a substantial U-shape. respectively, but this structure is not limiting, and it only needs to be a structure capable of locking in accordance with the structure on the vehicle side. 
     In this embodiment, the front locking portion  3024  is linked with both the first and second frameworks  3021 ,  3022  through the bases  3023 . However, the front locking portion  3024  is not limited to this form but may be linked directly with both the first and second frameworks  3021 ,  3022  not through the base  3023  as the rear locking portion  3025 . Moreover, the number of the front locking portions  3024  is not particularly limited but it may be one, or three or more. Either one of the front locking portion  3024  or the rear locking portion  3025  does not have to be present. 
     3-3. Foamed Resin Molded Body  3030   
     As illustrated in  FIGS. 24 and 25 , the foamed resin molded body  3030  is an in-mold foamed resin molded body of a foamed resin. The foamed resin molded body  3030  is a molded body by in-mold foam molding by filling pre-expanded resin particles obtained by pre-expanding expandable resin particles containing a resin and a foaming agent in a molding die and by re-foaming the pre-expanded resin particles in the molding die, and specific aspects of the resin, the foaming agent, the expandable resin particles, and the pre-expanded resin particles are as described above. The foamed resin is not particularly limited, but a foamed thermoplastic resin is usually used, and a foamed polystyrene-based resin, a foamed composite resin containing a polystyrene-based resin and a polyolefin-based resin, a foamed polyolefin-based resin, and the like are suitably used, and the foamed polystyrene-based resin or the foamed composite resin containing the polystyrene-based resin and the polyolefin-based resin is particularly preferable. The foamed polystyrene-based resin or the foamed composite resin containing the polystyrene-based resin and the polyolefin-based resin has small degrees of thermal expansion and thermal contraction and thus, they are particularly preferable from a viewpoint that deformation of the foamed resin molded body and the frame member is suppressed. 
     In the foamed resin molded body  3030 , an upper surface  3031  on which the occupant of the vehicle is seated and a bottom surface  3032  which is on a side fastened to the vehicle are formed. The foamed resin molded body  3030  has the rim part  3035  in which the frame member  3020  is embedded and defining the outer shape  3 S of the vehicle seat member  3010  in plan view of the vehicle seat member  3010 . The rim part  3035  is constituted by a front part  3035   a  located on a front of a seat, a pair of side parts  3035   c ,  3035   c  formed integrally with the front part  3035   a , located on right and left sides of the seat, extending rearward from both end portions of the front part  3035   a , and having vicinities of the rear ends inclined, and a rear part  3035   b  integrally formed with the side parts  3035   c ,  3035   c  and connecting the rear ends of the pair of side parts  3035   c ,  3035   c  in a state where the vehicle seat member  3010  is mounted. When the vehicle seat member  3010  is assembled in the vehicle, the front part  3035   a  in the rim part  3035  supports a thigh part of the occupant, and the rear part  3035   b  supports a buttock part of the occupant. 
     Specifically, as illustrated in  FIG. 26 , the upper surface  3031  of the foamed resin molded body  3030  is formed so as to hold the thigh part and the buttock part of the occupant through the upper seat member  3050  by being a curved surface dented downward. However, the shape and the thickness of the foamed resin molded body  3030  can be changed in various ways in accordance with a shape of the vehicle body side on which the vehicle seat member  3010  is mounted and is not limited to the illustrated embodiment. The upper surface  3031  of the foamed resin molded body  3030  may be substantially a flat shape, for example. 
     The foamed resin molded body  3030  includes an extension  3036  extending inward from the rim part  3035  so as to bridge the rim part  3035  inside of the rim part  3035 . In the third invention, a part extending along a predetermined direction in the extension is called an “extension part”. The extension may be made only of one extension part or may be formed of a plurality of extension parts. In this embodiment, the extension  3036  is constituted by a first extension part  3036 A extending in the longitudinal direction and a second extension part  3036 B extending in the transverse direction. The first extension part  3036 A and the second extension part  3036 B are linked by a linking portion  3036 C. In this embodiment, the extension  3036  is constituted by the plurality of extension parts  3036 A,  3036 B, but this is not limiting, and it may be constituted only by one extension part. For example, the extension  3036  may be constituted only by the first extension part  3036 A or may be constituted only by the second extension part  3036 B. When the extension  3036  includes a plurality of extension parts extending across the rim part  3035 , each of the plurality of extension parts may be provided along a predetermined direction. 
     In the rim part  3035 , a part connected to the extension  3036  is made a connecting part  3035 ′ and a part other than the connecting part  3035 ′ is made a not-connecting part  3035 ″. Specifically, the connecting part  3035 ′ of the rim part  3035  is connected to an end of each of the extension parts  3036 A,  3036 B of the extension  3036  and supports them. 
     In this embodiment, the frame member  3020  has the second framework  3022  (continuous part) in which the opposed parts  3022   a .  3022   a  opposed to each other across a space inside the rim part  3035  continue to each other. The first extension part  3036 A in the extension  3036  is formed so as to extend between the opposed parts  3022   a .  3022   a.    
     The extension  3036  in the foamed resin molded body  3030  is a part for reinforcing and holding the shape of the vehicle seat member  3010 . In the foamed resin molded body  3030 , by forming the extension  3036  in a space inside the rim part  3035 , a hollow portion  3038   a  is formed between the rim part  3035  and the extension  3036 . The hollow portion  3038   a  is provided for the purpose of reducing the weight of the foamed resin molded body  3030  or of accommodating the other members (a cushion material which is elastically deformed more easily than the foamed resin molded body  3030 , a member of a console box, and the like, for example) constituting the vehicle seat. In the illustrated embodiment, six pieces of the hollow portions  3038   a  are formed in the foamed resin molded body  3030 , but the number of the hollow portions  3038   a  is not limited. 
     The extension  3036  of the foamed resin molded body  3030  contains the foamed resin with a maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . In  FIGS. 25 to 27 , the foamed resin with the larger maximum point stress by bending is indicated in a dark color, and the foamed resin with the smaller maximum point stress by bending is indicated in a pale color. More specifically, an extending direction  3 L in which the first extension part  3036 A in the extension  3036  extends is matched with the longitudinal direction of the vehicle seat member  3010 , and the entire first extension part  3036 A contains the foamed resin with the maximum point stress by bending larger than that of the foamed resin forming the not-connecting part  3035 ″ of the rim part  3035 . As in the illustrated embodiment, if a plurality of extension parts is present in the extension  3036 , at least one extension part only needs to contain the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 , and the entirety of the at least one extension part is preferably formed by the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . 
     The larger the maximum point stress by bending of the foamed resin contained in each part of the foamed resin molded body  3030 , the higher the rigidity of the each part of the foamed resin molded body  3030  is, if the shapes and the dimensions are the same. In this embodiment, by molding the foamed resin molded body  3030  so that the extension  3036  contains the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 , the rigidity of the extension  3036  can be selectively improved. 
     In the third invention, the extension  3036  “contains” the foamed resin with the maximum point stress by bending larger (hereinafter, referred to as a “predetermined foamed resin” in some cases) than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035  only needs that the extension  3036  contains the predetermined foamed resin to such a degree that sufficient rigidity is given to at least one extension part, and the extension  3036  may further contain other foamed resins other than the predetermined foamed resin. At least one extension part in the extension  3036  preferably contains the predetermined foamed resin and more preferably, the at least one extension part is formed by the predetermined foamed resin. 
     In the third invention, the maximum point stress by bending (kPa) of the foamed resin is measured in accordance with a bending test provided for in ASTM D790 procedure A. 
     Conditions of the bending test are specifically as follows: 
     Testing instrument: TENSILON Universal Material Testing Instrument UCT-10T (ORIENTEC CORPORATION) 
     Test piece: 79.2 W×380 L×19.8 T thickness (mm) (without skin) 
     Number of test: 5 
     Test speed: 8.4 mm/min 
     Distance between support points: 316.7 (mm) 
     Maximum deflection: 64 mm 
     Distal-end jig: cradle wedge . . .  5 R, pressurized wedge . . .  5 R 
     Test piece conditioning/test environment: temperature: 23±+2C, Relative humidity (RH): 50±10%, 24 hours or more 
     In the third invention, the maximum point stress by bending measured under the aforementioned conditions of the foamed resin contained in the not-connecting part of the rim part in the foamed resin molded body is not particularly limited but it is within a range from 10 to 600 kPa or typically within a range from 100 to 500 kPa, for example. On the other hand, the maximum point stress by bending measured under the aforementioned conditions of the foamed resin contained in at least a part of the extension in the foamed resin molded body is higher than that of the foamed resin contained in the not-connecting part of the rim part and 1.2 to 5 times or typically 1.5 to 4 times of the maximum point stress by bending of the foamed resin contained in the not-connecting part of the rim part, for example. An absolute value of the maximum point stress by bending measured under the aforementioned conditions of the foamed resin contained in at least a part of the extension in the foamed resin molded body is 150 to 2,000 kPa or typically 250 to 1,200) kPa, for example. In the foamed resin molded body  3030 , the resin in the foamed resin constituting each part can be selected from the aforementioned types of resin and does not have to be formed by the resin of the same base. However, if the entire foamed resin molded body  3030  is constituted by the foamed body of the resin of the same base, each part of the foamed resin molded body  3030  is firmly coupled, which is preferable. If the entire foamed resin molded body  3030  is constituted by the foamed body of the same resin except that the maximum point stress by bending is different, each part of the foamed resin molded body  3030  is coupled further firmly, which is preferable. 
     Control of the maximum point stress by bending of the foamed resin is executed easily and preferably by controlling an expansion ratio of the foamed resin. With regard to the foamed resin constituted by the same resin material, the smaller the expansion ratio is, the larger the maximum point stress by bending is. The smaller the expansion ratio is, the larger the specific weight of the foamed resin is. Thus, in the third invention, in the aspect in which the maximum point stress by bending is increased by making the expansion ratio of the foamed resin smaller, by molding the foamed resin molded body so that the extension contains the foamed resin with a smaller expansion ratio and a larger maximum point stress by bending rather than the foamed resin contained by the not-connecting part of the rim part, an increase in the weight of the foamed resin molded body can be suppressed while rigidity of the extension is selectively improved. 
     In the aspect in which the maximum point stress by bending of the foamed resin is controlled by controlling the expansion ratio, a specific range of the expansion ratio is not particularly limited, but the not-connecting part  3035 ″ of the rim part  3035  contains the foamed resin with the expansion ratio of 21 to 60 times or 11 to 60 times, for example, and the extension  3036  contains the foamed resin with the expansion ratio of 2.5 to 20 times or 2.5 to 10 times, for example. The foamed resin molded body  3030  is preferably molded so that these ranges of the expansion ratio are satisfied, and the extension  3036  contains the foamed resin with the smaller expansion ratio than the expansion ratio of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . 
     Here, the expansion ratio of the foamed resin contained in each part of the foamed resin molded body  3030  can be acquired by the following procedure. 
     A weight (c) and a volume (d) of a test piece (e.g.: a cuboid piece with 50 mm×100 mm×10 mm) cut out of each part (parts whose expansion ratios are to be measured such as the extension parts  3036 A,  3036 B of the extension  3036 , the not-connecting part  3035 ″ of the rim part  3035 , the connecting part  3035 ′ of the rim part  3035 , and the like) of the foamed resin molded body  3030  (those dried at 40° C. for 20 hours or more after molding) are measured with effective figures of three digits or more, respectively, and density (g/cm 3 ) of the foamed molded body is acquired by an expression (c)/(d). An inverse number of the density, that is, the expression (d)/(c) is the expansion ratio. 
     Moreover, in addition to the extension  3036 , the connecting part  3035 ′ of the rim part  3035  connected to the extension  3036  preferably contains the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . If a plurality of the extension parts  3036 A,  3036 B are present in the extension  3036 , at least one of the extension parts  3036 A,  3036 B ( 3036 A, for example) and the connecting part  3035 ′ of the rim part  3035  connected to the at least one extension part preferably contain the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . 
     Here, while the first and second frameworks  3021 ,  3022  of the frame member  3020  are embedded in the rim part  3035  in the foamed resin molded body  3030 , if the extension  3036  is formed by the foamed resin with the same maximum point stress by bending as that of the not-connecting part  3035 ″ of the rim part  3035  and if the extension  3036  and/or the rim part  3035  is not reinforced by another means, when a heat is input into the vehicle seat member  3010  (or when the input heat is released), apparent thermal expansion amounts (thermal contraction amounts) are different between the rim part  3035  in the state where the first and second frameworks  3021 ,  3022  of the frame member  3020  are embedded in the foamed resin molded body  3030  and the extension  3036  extending inside the rim part  3035  where the frame member  3020  is not present. As a result, the compression stress and the tensile stress non-uniformly act as the thermal stress on the extension  3036  surrounded by the rim part  3035 , and the center of the extension  3036  is deformed easily so as to be curved upward, for example. Particularly, such phenomenon is remarkable in the first extension part  3036 A formed along the longitudinal direction in the extension  3036 . 
     In this embodiment, by forming the first extension part  3036 A extending along the longitudinal direction in the extension  3036  extending inside the rim part  3035  and the connecting part  3035 ′ connected to the first extension part  3036 A in the rim part  3035  by the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 , the extension  3036  is reinforced. As a result, even if the extension  3036  is thermally expanded or thermally contracted, deformation of the extension  3036  by the thermal stress can be suppressed, and dimensional accuracy of the vehicle seat member  3010  can be ensured. According to this embodiment, since the first extension part  3036 A of the extension  3036  and the connecting part  3035 ′ connected to the first extension part  3036 A in the rim part  3035  are selectively reinforced, and the not-connecting part  3035 ″ of the rim part  3035  can be constituted by an ordinary foamed resin, margins of a weight increase and a cost increase in the entire foamed resin molded body  3030  are small. Moreover, according to this embodiment, since reinforcement such that the first extension part  3036 A of the extension  3036  is formed thick is not needed, it is less likely that design or application is limited. 
     Particularly in this embodiment, the second framework  3022  having a structure in which the pair of opposed parts  3022   a ,  3022   a  opposed to each other continues to each other is embedded in the rim part  3035 , and the first extension part  3036 A of the extension  3036  is formed so as to extend between the opposed parts  3022   a ,  3022   a . In this constitution, since the both sides of the first extension part  3036 A of the extension  3036  are restrained, if the first extension part  3036 A is formed by the foamed resin with the same maximum point stress by bending as that of the not-connecting part  3035 ″ of the rim part  3035  and the extension  3036  and/or the rim part  3035  is not reinforced by another means, the extension  3036  including the first extension part  3036 A is deformed particularly easily by the thermal expansion and thermal contraction. In this embodiment, by molding the first extension part  3036 A and the connecting part  3035 ′ connected to the first extension part  3036 A in the rim part  3035  so as to contain the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 , the deformation of the extension  3036  including the first extension part  3036 A can be further effectively suppressed. 
     Moreover, as in this embodiment, if the parts including the first framework  3021  and the second framework  3022  of the frame member  3020  continuously circle around along the outer shape  3 S of the vehicle seat member  3010 , deformation by the thermal stress is suppressed over the entire circumference of the rim part  3035 . Thus, if the extension  3036  is formed by the foamed resin with the same maximum point stress by bending as that of the not-connecting part  3035 ″ of the rim part  3035  and the extension  3036  and/or the rim part  3035  is not reinforced by another means, the extension  3036  formed inside the rim part  3035  is deformed further easily. Even in such a case, in this embodiment, by molding the extension  3036  so as to contain the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 , the deformation of the extension  3036  can be further effectively suppressed. 
     3-4. Method of Manufacturing Vehicle Seat Member  3010   
     The method of manufacturing the vehicle seat member  3010  will be described below by referring to  FIGS. 28 and 29 . In  FIG. 28 , each step of the method of manufacturing will be described by a schematic sectional view at a position corresponding to a I-I line arrow-view sectional view illustrated in  FIG. 27 . In  FIG. 29 , each step of the method of manufacturing will be described by a schematic sectional view at a position corresponding to a II-II line arrow-view sectional view illustrated in  FIG. 27 . 
     An embodiment described below is an example in which the expansion ratio of a foamed resin constituting the first extension part  3036 A in the extension  3036  of the foamed resin molded body  3030  and the part connected to the first extension part  3036 A in the connecting part  3035 ′ of the rim part  3035  is made smaller than that of the foamed resin constituting the not-connecting part  3035 ″ of the rim part  3035  so as to increase the maximum point stress by bending. 
     An outline of the method of manufacturing the vehicle seat member  3010  of this embodiment is as follows. As illustrated in  FIG. 28(A)  and  FIG. 29(A) , the frame member  3020  is disposed so as to be located in a cavity  3073  of a molding die  3007  and then, pre-expanded resin particles  3030 A.  3030 B obtained by pre-expanding the expandable resin particles containing the resin and the foaming agent are filled therein. Subsequently, as illustrated in  FIG. 28(B)  and  FIG. 29(B) , the pre-expanded resin particles  3030 A are expanded by supplying steam into the molding die  3007  so as to mold the foamed resin molded body  3030 . After that, as illustrated in  FIG. 28(C)  and  FIG. 29(C) , the foamed resin molded body  3030  is removed from the molding die  3007  together with the frame member  3020  and cooled by heat release or the like. 
     The foamed resin molded body  3030  usually has a property of slightly contracting when the remaining heat during the foam molding is released after the molding. On the other hand, in the frame member  3020  constituted by a material such as metal, the dimensions are not substantially changed as compared to the foamed resin molded body  3030  before and after the molding of the foamed resin molded body  3030 . Therefore, if the extension  3036  is formed by the foamed resin with the same maximum point stress by bending as that of the not-connecting part  3035 ″ of the rim part  3035  and the extension  3036  and/or the rim part  3035  is not reinforced by another means, as illustrated in  FIG. 30(A) , the foamed resin molded body  3030  is molded by the molding die  3007  made of a first die  3071  and a second die  3072 , and as illustrated in  FIG. 30(B) , for a period of time immediately after the molding until the foamed resin molded body  3030  is removed from the molding die  3007  and the foamed resin molded body  3030  releases heat, the foamed resin molded body  3030  thermally contracts. At this time, since the both sides of the extension  3036  where the frame member  3020  is not present is restrained by the rim part  3035  where the second framework  3022  of the frame member  3020  is present, the compression stress and the tensile stress non-uniformly act as the thermal stress on the extension  3036 , and the extension  3036  is deformed easily so as to be curved upward from the center. 
     In view of these points, in this embodiment, the vehicle seat member  3010  is manufactured as follows. First, the frame member  3020  is prepared. The structure and the material of the frame member  3020  are as described above. Subsequently, in plan view of the vehicle seat member  3010 , the frame member  3020  is disposed in the molding die  3007  so that the first framework  3021  and the second framework  3022  of the frame member  3020  are disposed along the outer shape  3 S of the vehicle seat member  3010  (placing step). 
     As the molding die  3007 , a closed molding die having a large number of pores can be used. 
     As illustrated in  FIG. 28(A)  and  FIG. 29(A) , the molding die  3007  is made of the first die  3071  and the second die  3072  and is constituted such that a cavity  3073  according to the foamed resin molded body  3030  is formed in the molding die  3007  when the first die  3071  and the second die  3072  are clamped. 
     Subsequently, as illustrated in  FIG. 28(A)  and  FIG. 29(A) , the first die  3071  and the second die  3072  in which the frame member  3020  is disposed therein is temporarily clamped (cracking) and then, the pre-expanded resin particles  3030 A,  3030 B are filled and clamped. 
     At this time, at a position in the cavity  3073  corresponding to a part requiring a foamed resin with a large maximum point stress by bending in the foamed resin molded body  3030  to be manufactured, the pre-expanded resin particles  3030 A with a small bulk expansion ratio are filled, while at a position in the cavity  3073  corresponding to a part other than the part requiring the foamed resin with the large maximum point stress by bending in the foamed resin molded body  3030  to be manufactured, the pre-expanded resin particles  3030 B with a large bulk expansion ratio are filled. Specifically, in this embodiment, at the positions in the cavity  3073  corresponding to the first extension part  3036 A in the extension  3036  and the part connected to the first extension part  3036 A in the connecting part  3035 ′ of the rim part  3035 , the pre-expanded resin particles  3030 A are filled, while at the positions in the cavity  3073  corresponding to the parts of the extension  3036  and the rim part  3035  other than the first extension part  3036 A of the extension  3036  and the part connected to the first extension part  3036 A in the connecting part  3035 ′ of the rim part  3035 , the pre-expanded resin particles  3030 B with the bulk expansion ratio larger than that of the pre-expanded resin particles  3030 A are filled. 
     Subsequently, as illustrated in  FIG. 28(B) , the pre-expanded resin particles  3030 A,  3030 B are secondarily foamed by heating the inside of the cavity  3073  of the molding die  3007  by steam, gaps among the pre-expanded resin particles  3030 A,  3030 B are filled, and the pre-expanded resin particles  3030 A.  3030 B are integrated by fusing them to each other so that the foamed resin molded body  3030  is molded (molding step). 
     A fusion rate among the foamed particles derived from the pre-expanded resin particles of the foamed resin molded body  3030  is not particularly limited but it is 50 to 100%, more preferably 70 to 100%, and further preferably 90 to 100%. 
     The fusion rate, here, expresses a rate in percentage of the number of foamed particles fractured inside the particles in the total number of foamed particles derived from the pre-expanded resin particles appearing on a section when the foamed resin molded body  3030  is bent and fractured. Measurement of the fusion rate can be specifically performed by the following procedure. A cut line with a depth of approximately 5 mm is made by a cutter knife along the center of the foamed resin molded body. After that, the foamed resin molded body is manually divided into two parts along this cut line. With regard to the foamed particles on the fractured surface, the number (a) of the particles fractured in the particles within a predetermined range from 100 to 150 particles and the number (b) of the particles fractured on an interface between the particles are counted. A value obtained by substituting the results in an expression [(a)/((a)+(b))]×100 is made a fusion rate (%). 
     The fusion rate can be controlled by controlling an amount of heat when heating/foaming, for example. 
     As a result, the foamed resin molded body  3030  containing the rim part  3035  and the extension  3036  can be molded in the molding die  3007 . The molded extension  3036  contains, in the first extension part  3036 A, the foamed resin with the expansion ratio smaller and the maximum point stress by bending larger than those of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . Moreover, in this embodiment, the part connected to the first extension part  3036 A in the connecting part  3035 ′ of the rim part  3035  also contains the foamed resin with the expansion ratio smaller and the maximum point stress by bending larger than those of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . The molded rim part  3035  has the first framework  3021  and the second framework  3022  in the frame member  3020  embedded and forms the outer shape  3 S of the vehicle seat member  3010 . In the molded extension  3036 , the first extension part  3036 A extends between the pair of side parts  3035   c ,  3035   c  of the rim part  3035 , and the second extension parts  3036 B,  3036 B extend between the front part  3035   a  and the rear part  3035   b  of the rim part  3035 . 
     Subsequently, the foamed resin molded body  3030  is removed from the molding die  3007 , and the vehicle seat member  3010  of this embodiment in which the foamed resin molded body  3030  and the frame member  3020  are integrated can be obtained. Here, during and after the removal of the foamed resin molded body  3030  from the molding die  3007 , remaining heat during the molding is released, and the foamed resin molded body  3030  contracts. 
     In the embodiment, since the first extension part  3036 A is constituted to contain the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 , rigidity of the first extension part  3036 A is improved. As a result, the deformation of the extension  3036  including the first extension part  3036 A by the thermal stress can be suppressed. As a result, the vehicle seat member  3010  with high dimensional accuracy can be manufactured. According to this embodiment, since the not-connecting part  3035 ″ of the rim part  3035  can be constituted by the foamed resin with a large expansion ratio, margins of a weight increase and a cost increase in the entire foamed resin molded body  3030  are small. Moreover, according to this embodiment, since reinforcement such that the first extension part  3036 A of the extension  3036  is formed thick is not needed, it is less likely that design or application is limited. 
     In this embodiment, the frame member  3020  has the second framework  3022 , and the second framework  3022  has the continuous part in which the opposed parts  3022   a ,  3022   a  opposed to each other across the space inside the rim part  3035  continue to each other. When the foamed resin molded body  3030  is molded, the extension  3036  is molded so as to have the first extension part  3036 A extending between the opposed parts  3022   a ,  3022   a . Therefore, since the both sides of the first extension part  3036 A of the extension  3036  is restrained by the side parts  3035   c ,  3035   c  of the rim part  3035  in which the opposed parts  3022   a ,  3022   a  of the second framework  3022  of the frame member  3020  are embedded, as illustrated in  FIG. 30 , if the first extension part  3036 A is formed by the foamed resin with the same maximum point stress by bending as that of the not-connecting part  3035 ″ of the rim part  3035  and the extension  3036  and/or the rim part  3035  is not reinforced by another means, the extension  3036  including the first extension part  3036 A is deformed easily by the thermal contraction. Particularly since the parts including the first framework  3021  and the second framework  3022  of the frame member  3020  are made to continuously circle around along the outer shape  3 S of the vehicle seat member  3010 , such deformation occurs easily. In this embodiment, by molding the foamed resin molded body  3030  so that the first extension part  3036 A which is one of extension parts of the extension  3036  contains the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035  during the molding step, the first extension part  3036 A and the extension  3036  including that can be reinforced, and the aforementioned deformation can be suppressed. 
     Third Invention/Second Embodiment 
     The vehicle seat member  3010  according to a second embodiment of the third invention and the method of manufacturing the same will be described below by referring to  FIGS. 31 and 32 . A point that the vehicle seat member  3010  according to the second embodiment is different from the vehicle seat member  3010  according to the first embodiment is that, in the extension  3036 , in addition to the first extension part  3036 A extending in the longitudinal direction of the outer shape  3 S of the vehicle seat member  3010 , the second extension parts  3036 B,  3036 B extending in the transverse direction contain the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . The same constitutions as those in the first embodiment are given the same reference numerals and detailed description will be omitted. 
     In this embodiment, the extension  3036  is reinforced by molding the foamed resin molded body  3030  such that the first extension part  3036 A and the second extension parts  3036 B,  3036 B in the extension  3036  contain the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 , respectively. As a result, even if the extension  3036  is thermally expanded or thermally contracted, deformation of the extension  3036  by the thermal stress can be suppressed, and dimensional accuracy of the vehicle seat member  3010  can be ensured. 
     In this embodiment, the deformation of the extension  3036  can be suppressed more efficiently by molding the foamed resin molded body  3030  such that the part connected to the first extension part  3036 A in the connecting part  3035 ′ of the rim part  3035  further contains the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . 
     In this embodiment, the frame member  3020  has a structure in which the first framework  3021  and the part  3022   b  along the rear edge  3   s B in the second framework  3022  opposed with the first framework  3021  continue to each other. The first framework  3021  and the part  3022   b  along the rear edge  3   s B in the second framework  3022  are embedded in the rim part  3035 , and the second extension parts  3036 B,  3036 B of the extension  3036  are formed so as to extend between the first framework  3021  and the part  3022   b  along the rear edge  3   s B in the second framework  3022 , respectively. In this constitution, since both sides of the second extension parts  3036 B,  3036 B of the extension  3036  are restrained, respectively, if the second extension parts  3036 B,  3036 B of the extension  3036  are formed by the foamed resin with the same maximum point stress by bending as that of the not-connecting part  3035 ″ of the rim part  3035  and the extension  3036  and/or the rim part  3035  is not reinforced by another means, the extension  3036  including the second extension parts  3036 B.  3036 B is deformed particularly easily by the thermal expansion and thermal contraction. In this embodiment, the deformation of the extension  3036  including the second extension parts  3036 B,  3036 B can be suppressed more effectively by molding the second extension parts  3036 B,  3036 B so as to contain the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . 
     Manufacture of the vehicle seat member  3010  according to the second embodiment can be performed by the procedure similar to the first embodiment. The second embodiment is also an example in which the maximum point stress by bending is increased by making the expansion ratio of the foamed resin constituting the extension  3036  of the foamed resin molded body  3030  and the part connected to the first extension part  3036 A in the connecting part  3035 ′ of the rim part  3035  smaller than the foamed resin constituting the not-connecting part  3035 ″ of the rim part  3035 . 
     First, in plan view of the vehicle seat member  3010 , the frame member  3020  is disposed in the molding die so that the first framework  3021  and the second framework  3022  of the frame member  3020  are disposed along the outer shape  3 S of the vehicle seat member  3010  (placing step). Here, the molding die is made of the first die and the second die and is constituted such that, when the first die and the second die are clamped, a cavity according to the foamed resin molded body  3030  is formed in the molding die. 
     Subsequently, after the first die and the second die in which the frame member  3020  is disposed therein are temporarily clamped (cracking), the pre-expanded resin particles obtained by pre-expanding the expandable resin particles containing the resin and the foaming agent are filled and clamped. At this time, at the position in the cavity  3073  corresponding to the first extension part  3036 A and the second extension part  3036 B in the extension  3036  as well as the part connected to the first extension part  3036 A in the connecting part  3035 ′ of the rim part  3035 , the pre-expanded resin particles with a relatively small bulk expansion ratio are filled, and at the position in the cavity  3073  corresponding to the other parts of the extension  3036  and the rim part  3035 , the pre-expanded resin particles with a relatively large bulk expansion ratio are filled. 
     Subsequently, the pre-expanded resin particles are secondarily foamed by heating the inside of the cavity of the molding die by steam or the like, gaps among the pre-expanded resin particles are filled, and the pre-expanded resin particles are integrated by fusing them to each other so that the foamed resin molded body  3030  is molded (molding step). 
     As a result, the foamed resin molded body  3030  including the rim part  3035  and the extension  3036  can be molded in the molding die. The molded extension  3036  contains the foamed resin in the first extension part  3036 A and the second extension part  3036 B with the maximum point stress larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . Moreover, in this embodiment, the part connected to the first extension part  3036 A in the connecting part  3035 ′ of the rim part  3035  also contains the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . The molded rim part  3035  has the first framework  3021  and the second framework  3022  in the frame member  3020  embedded and forms the outer shape  3 S of the vehicle seat member  3010 . In the molded extension  3036 , the first extension part  3036 A extends between the pair of side parts  3035   c ,  3035   c  of the rim part  3035  and the second extension parts  3036 B,  3036 B extend between the front part  3035   a  and the rear part  3035   b  of the rim part  3035 . 
     Subsequently, the foamed resin molded body  3030  is removed from the molding die, and the vehicle seat member  3010  of this embodiment in which the foamed resin molded body  3030  and the frame member  3020  are integrated can be obtained. Here, during and after the removal of the foamed resin molded body  3030  from the molding die, remaining heat during the molding is released, and the foamed resin molded body  3030  contracts. 
     In this embodiment, even if the extension  3036  thermally contracts, since the first extension part  3036 A and the second extension parts  3036 B,  3036 B are constituted to contain the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 , deformation of the first extension part  3036 A and the second extension parts  3036 B,  3036 B as well as the extension  3036  including them by the thermal stress can be suppressed. As a result, the vehicle seat member  3010  with high dimensional accuracy can be manufactured. 
     In this embodiment, one ends of the second extension parts  3036 B,  3036 B of the extension  3036  are restrained by the front part  3035   a  of the rim part  3035  in which the first framework  3021  of the frame member  3020  is embedded, and the other ends of the second extension parts  3036 B.  3036 B of the extension  3036  are restrained by the rear part  3035   b  of the rim part  3035  in which the part  3022   b  along the rear edge  3   s B in the second framework  3022  of the frame member  3020  is embedded. Similarly, as described in relation with the first embodiment, both sides of the first extension part  3036 A of the extension  3036  are also restrained by the side parts  3035   c ,  3035   c  of the rim part  3035  in which the opposed parts  3022   a ,  3022   a  of the second framework  3022  of the frame member  3020  are embedded. Thus, if the first extension part  3036 A and the second extension parts  3036 B,  3036 B are formed by the foamed resin with the same maximum point stress by bending as that of the not-connecting part  3035 ″ of the rim part  3035  and the extension  3036  and/or the rim part  3035  is not reinforced by another means, the extension  3036  is deformed easily by the thermal contraction. Moreover, in this embodiment, since the parts including the first framework  3021  and the second framework  3022  of the frame member  3020  are made to continuously circle around along the outer shape  3 S of the vehicle seat member  3010 , such deformation can occur particularly easily. In this embodiment, the first extension part  3036 A and the extension  3036  including it are reinforced and the aforementioned deformation is suppressed by, during the molding, molding the foamed resin molded body  3030  such that the first extension part  3036 A and the second extension parts  3036 B,  3036 B of the extension  3036  contain the foamed resin with the maximum point stress by bending larger than that of the foamed resin contained in the not-connecting part  3035 ″ of the rim part  3035 . 
     Some embodiments of the third invention have been described above in detail, but the third invention is not limited to the aforementioned embodiments but is capable of various design changes within a range not departing from the scope of the third invention described in “Solution to Problem”. 
     &lt;Fourth Invention&gt; 
     Some embodiments of a vehicle seat member and a vehicle seat according to the fourth invention will be described below by referring to the drawings. However, the scope of the fourth invention is not limited to the individual embodiments. 
     Fourth Invention/First Embodiment 
     4-1. Vehicle Seat Member  4010   
     A first embodiment of a vehicle seat member and a method of manufacturing the same will be described on the basis of  FIGS. 33 to 37 . 
     As illustrated in  FIGS. 33 and 34 , the vehicle seat member  4010  includes a frame member  4020  and a foamed resin molded body  4030  in which at least a part of the frame member  4020  is embedded as a basic constitution. 
     An entire shape of the vehicle seat member  4010  is not particularly limited but as illustrated in  FIG. 35 , a rectangular shape in plan view is common. In the description, a rectangle refers to a square such as a rectangle, a regular square, and the like, and not only the rectangle or the regular square, it may be a shape such as a trapezoid or a parallelogram. In the description, the rectangle also includes a substantial rectangle, and corner parts may be rounded, or a part or the whole of a side constituting the rectangle may be a bent side, for example. 
     In this embodiment, as illustrated in  FIG. 35 , an outer shape  4 S of the vehicle seat member  4010  in plan view is a rectangle having a short side and a long side and has a shape having a transverse direction and a longitudinal direction. The outer shape  4 S includes a right edge  4   s R and a left edge  4   s L constituting the short sides, a front edge  4   s F and a rear edge  4   s B constituting the long sides as four sides, and corners  4   s C constituting four corners. The terms front, rear, left, and right in this embodiment refer to directions when an advancing (front) direction of the vehicle is seen from the vehicle in a state where an occupant is seated in the vehicle. 
     The vehicle seat member  4010  of this embodiment may be made into a vehicle seat  4001  by laminating/disposing an upper seat member  4050  such as a cushion material or the like as appropriate from a side of an upper surface  4011  (upper surface  4031 ) of the vehicle seat member  4010  (foamed resin molded body  4030 ) as illustrated in  FIG. 36 , for example. Moreover, the vehicle seat member  4010  may be covered by an appropriate exterior material together with the cushion material or the like so as to have the vehicle seat  4001 . 
     4-2. Frame Member  4020   
     As illustrated in  FIGS. 33 to 35 , the frame member  4020  is embedded in order to apply required shape retaining properties and strength to the foamed resin molded body  4030 . The frame member  4020  is usually constituted by a material whose dimensions are not substantially changed as compared to the foamed resin molded body  4030  under a condition that the foamed resin molded body  4030  is molded or a metal material such as steel or aluminum, for example. 
     The frame member  4020  includes first and second frameworks  4021 ,  4022  extending inside the foamed resin molded body  4030  along the outer shape  4 S of the vehicle seat member  4010  in plan view, a pair of bases  4023 ,  4023  linked with end portions of the first and second frameworks  4021 ,  4022 , and a reinforcing portion  4026 . The second framework  4022  has a structure in which a pair of opposed parts  4022   a .  4022   a  opposed to each other continues to each other, and in the description, the second framework  4022  is called a “continuous part” of the frame member  4020  in some cases. 
     In the illustrated embodiment, the reinforcing portion  4026  is disposed so as to follow a opposed direction of the pair of opposed parts  4022   a ,  4022   a  of the second framework  4022 , and both ends of the reinforcing portion  4026  are linked with the pair of opposed parts  4022   a ,  4022   a  of the second framework  4022 , respectively. Linking between the pair of opposed parts  4022   a ,  4022   a  of the second framework  4022  and the both ends of the reinforcing portion  4026  can be performed by means such as welding and bonding. Moreover, the pair of opposed parts  4022   a ,  4022   a  of the second framework  4022  and the reinforcing portion  4026  may be constituted by an integral member. The reinforcing portion  4026  of the frame member  4020  only needs to extend so as to follow at least one of the directions in which an extension  4036  of the foamed resin molded body  4030  which will be described later extends and to be embedded in the extension  4036  and does not have to be linked with the framework of the frame member  4020  as illustrated. However, in the constitution in which the second framework  4022  and the reinforcing portion  4026  are linked in the frame member  4020 , it is preferable since an effect of suppressing deformation of the extension  4036  which will be described later is particularly high. Moreover, since the second framework  4022  and the reinforcing portion  4026  are linked in the frame member  4020 , rigidity of the second framework  4022  is improved, and the frame member  4020  has an entire structure that is not deflected easily and thus, disposition of the frame member  4020  in a molding die  4007  is easy in the placing step which will be described later, and particularly assembling and installing the frame member  4020  in the molding die  4007  by using a robot is easy. 
     In the illustrated embodiment, the reinforcing portion  4026  of the frame member  4020  is constituted by one member extending so as to be embedded across an entire first extension part  4036 A which is one of the extension parts of the extension  4036  of the foamed resin molded body  4030 , that is, across the entire first extension part  4036 A from one end to the other end connected to a rim part  4035 , which will be described later. However, this embodiment is not limiting, but the reinforcing portion  4026  of the frame member  4020  may be constituted by a plurality of members disposed along the direction in which the extension  4036  of the foamed resin molded body  4030  extends and extending along the direction. 
     The frame member  4020  further includes a front locking portion  4024  mounted on each of the bases  4023  and a rear locking portion  4025  mounted on the second framework  4022 . In this embodiment, as the first and second frameworks  4021 ,  4022 , the front and rear locking portions  4024 ,  4025 , and the reinforcing portion  4026 , a wire rod (wire) made of steel or aluminum having a diameter of approximately 3 to 6 mm is used, for example, but it may be a band-shaped or tubular steel material made of metal, for example. Moreover, the frame member  4020  may be manufactured by punch molding and press molding from a steel plate. In the fourth invention, the framework and the reinforcing portion are preferably a linear framework and a linear reinforcing portion as illustrated, respectively. The term “linear” here is not limited to a wire rod such as a wire but may be the aforementioned band-shaped, tubular, or the like, for example, and is not particularly limited as long as it extends substantially along one line. 
     The first framework  4021  of the frame member  4020  extends along a part of the center of the front edge  4   s F in its vicinity, and the second framework  4022  extends along a part of both sides of the front edge  4   s F, the right edge  4   s R, the left edge  4   s L, the rear edge  4   s B, and each of the corners  4   s C in their vicinities. The frame member  4020  is embedded at a spot slightly inward from the outer peripheral surface  4033  of the foamed resin molded body  4030  defining the outer shape  4 S so as to follow the outer shape  4 S of the vehicle seat member  4010 . 
     As described above, the first and second frameworks  4021  and  4022  of the frame member  4020  continuously circle around along the outer shape  4 S of the vehicle seat member  4010  together with the pair of bases  4023 ,  4023  connecting them. In this embodiment, the parts including the first and second frameworks  4021 ,  4022  of the frame member  4020  continuously circle around along the outer shape  4 S of the vehicle seat member  4010 , but the first and second frameworks  4021 ,  4022  of the frame member  4020  may circle around intermittently along the outer shape  4 S of the vehicle seat member  4010 , for example. That is, not limited to this form, the framework may be disposed only on a part of a part along the outer shape  4 S. For example, it may be so constituted that the second framework  4022  is not linked with the bases  4023 ,  4023  but extends along the rear edge  4   s B. Moreover, the number of the frameworks constituting the frame member  4020  is not limited to two but the number may be one, or three or more. 
     The front locking portion  4024  and the rear locking portion  4025  constituting the frame member  4020  are parts by which the vehicle seat member  4010  is locked on the vehicle. The front locking portion  4024  is linked with the base  4023  by welding, bonding, or the like, for example, and protrudes downward from the base  4023 . A distal end part  4024   a  of the front locking portion  4024  is curved having a substantial U-shape and is exposed from the foamed resin molded body  4030 , and a base end part  4024   b  is embedded in the foamed resin molded body  4030  together with the base  4023 . More specifically, the base end part  4024   b  is embedded in the foamed resin molded body  4030  by the entire periphery thereof. As a result, even if a force in the pulling-out direction is applied when the vehicle seat member  4010  of this embodiment is locked on the vehicle through the distal end part  4024   a  of the front locking portion  4024 , the front locking portion  4024  is held by the foamed resin molded body  4030 , and resistance against the force in the pulling-out direction can be improved.
 
Moreover, the rear locking portion  4025  protrudes rearward from a center along the rear edge  4   s B in the second framework  4022 . The distal end part  4025   a  of the rear locking portion  4025  is curved having a substantial U-shape and is exposed from the foamed resin molded body  4030 , and the base end part  4025   b  is embedded in the foamed resin molded body  4030 .
 
     In this embodiment, the distal end parts  4024   a ,  4025   a  of the front locking portion  4024  and the rear locking portion  4025  are formed by bending a wire rod into a substantial U-shape, respectively, but this structure is not limiting, and it only needs to be a structure capable of locking in accordance with the structure on the vehicle side. 
     In this embodiment, the front locking portion  4024  is linked with both the first and second frameworks  4021 ,  4022  through the base  4023 . However, the front locking portion  4024  is not limited to this form but may be linked directly with both the first and second frameworks  4021 ,  4022  not through the base  4023  as the rear locking portion  4025 . Moreover, the number of the front locking portions  4024  is not particularly limited but it may be one, or three or more. Either one of the front locking portion  4024  or the rear locking portion  4025  does not have to be present. 
     4-3. Foamed Resin Molded Body  4030   
     As illustrated in  FIGS. 33 and 34 , the foamed resin molded body  4030  is an in-mold foamed molded body of a foamed resin. The foamed resin is not particularly limited, but a foamed thermoplastic resin is usually used, and a foamed polystyrene-based resin, a foamed composite resin containing a polystyrene-based resin and a polyolefin-based resin, a foamed polyolefin-based resin, and the like are suitably used, and the foamed polystyrene-based resin or the foamed composite resin containing the polystyrene-based resin and the polyolefin-based resin is particularly preferable. The foamed polystyrene-based resin or the foamed composite resin containing the polystyrene-based resin and the polyolefin-based resin have small degrees of thermal expansion and thermal contraction and thus, they are particularly preferable from a viewpoint that deformation of the foamed resin molded body and the frame member is suppressed. The expansion rate can be adjusted as appropriate in accordance with the type of the foamed resin, but it is approximately 10 to 50 times in general or approximately 20 to 40 times typically. 
     In the foamed resin molded body  4030 , an upper surface  4031  on which the occupant of the vehicle is seated and a bottom surface  4032  which is a side fastened to the vehicle are formed. The foamed resin molded body  4030  includes a rim part  4035  in which the frame member  4020  is embedded and defining the outer shape  4 S of the vehicle seat member  4010  in plan view of the vehicle seat member  4010 . The rim part  4035  is constituted by a front part  4035   a  located on a front of a seat, a pair of side parts  4035   c .  4035   c  formed integrally with the front part  4035   a , located on right and left sides of the seat, extending rearward from both end portions of the front part  4035   a , and having vicinities of the rear ends inclined, and a rear part  4035   b  integrally formed with the side parts  4035   c .  4035   c  and connecting the rear ends of the pair of side parts  4035   c ,  4035   c  in a state where the vehicle seat member  4010  is mounted. When the vehicle seat member  4010  is assembled in the vehicle, the front part  4035   a  in the rim part  4035  supports a thigh part of the occupant, and the rear part  4035   b  supports a buttock part of the occupant. 
     Specifically, as illustrated in  FIG. 36 , the upper surface  4031  of the foamed resin molded body  4030  is formed so as to hold the thigh part and the buttock part of the occupant through the upper seat member  4050  by being a curved surface dented downward. However, the shape and the thickness of the foamed resin molded body  4030  can be changed in various ways in accordance with a shape of the vehicle body side on which the vehicle seat member  4010  is mounted and is not limited to the illustrated embodiment. The upper surface  4031  of the foamed resin molded body  4030  may be substantially a flat shape, for example. 
     The foamed resin molded body  4030  includes an extension  4036  extending inward from the rim part  4035  so as to bridge the rim part  4035  inside of the rim part  4035 . In this embodiment, the extension  4036  is constituted by the first extension part  4036 A extending in the longitudinal direction and a second extension part  4036 B extending in the transverse direction. The first extension part  4036 A and the second extension part  4036 B are linked by a linking portion  4036 C. In this embodiment, the extension  4036  is constituted by the plurality of extension parts  4036 A,  4036 B, but this is not limiting, and it may be constituted only by one extension part. The extension  4036  may be constituted only by the first extension part  4036 A or may be constituted only by the second extension part  4036 B, for example. When the extension  4036  includes a plurality of extension parts extending across the rim part  4035 , each of the plurality of extension parts may be provided along a predetermined direction. 
     In this embodiment, the frame member  4020  has a second framework  4022  (continuous part) in which the opposed parts  4022   a ,  4022   a  opposed to each other across the space inside the rim part  4035  continue to each other. The first extension part  4036 A in the extension  4036  is formed so as to extend between the opposed parts  4022   a ,  4022   a.    
     In the foamed resin molded body  4030 , the extension  4036  is a part for holding a shape of the vehicle seat member  4010 . By forming the extension  4036  in the space inside the rim part  4035  in the foamed resin molded body  4030 , a hollow portion  4038   a  is formed between the rim part  4035  and the extension  4036 . The hollow portion  4038   a  is provided for the purpose of reducing the weight of the foamed resin molded body  4030  or of accommodating the other members (a cushion material which is elastically deformed more easily than the foamed resin molded body  4030 , a member of a console box, and the like) constituting the vehicle seat. In the illustrated embodiment, six pieces of the hollow portions  4038   a  are formed in the foamed resin molded body  4030 , but the number of the hollow portions  4038   a  is not limited. 
     As illustrated in  FIGS. 33 to 35 , in the extension  4036  of the foamed resin molded body  4030 , the reinforcing portion  4026  of the frame member  4020  extending along an extending direction  4 L of the first extension part  4036 A is embedded. More specifically, the extending direction  4 L in which the first extension part  4036 A in the extension  4036  extends is matched with the longitudinal direction of the vehicle seat member  4010 , and the reinforcing portion  4026  of the frame member  4020  extends along the first extension part  4036 A extending in the extending direction  4 L which is the longitudinal direction and is embedded. As in the illustrated embodiment, if the plurality of extension parts is present in the extension  4036 , it is only necessary that the reinforcing portion extending along the extending direction is embedded in at least one of the extension parts. 
     If the first and second frameworks  4021 ,  4022  of the frame member  4020  are embedded in the rim part  4035  in the foamed resin molded body  4030  but the reinforcing portion  4026  of the frame member  4020  is not embedded in the extension  4036 , when a heat is input into the vehicle seat member  4010  (or when the input heat is released), apparent thermal expansion amounts (thermal contraction amounts) are different between the rim part  4035  in the state where the first and second frameworks  4021 ,  4022  of the frame member  4020  in the foamed resin molded body  4030  are embedded and the extension  4036  extending inside the rim part  4035  where the frame member  4020  is not present. As a result, the compression stress and the tensile stress non-uniformly act as the thermal stress on the extension  4036  surrounded by the rim part  4035 , and the center of the extension  4036  is deformed easily so as to be curved upward, for example. Particularly, such phenomenon is remarkable in the first extension part  4036 A formed along the longitudinal direction in the extension  4036 . 
     In this embodiment, the frame member  4020  includes not only the first framework  4021  and the second framework  4022  but also the reinforcing portion  4026 , and by embedding this reinforcing portion  4026  in the first extension part  4036 A extending along the longitudinal direction in the extension  4036  extending inside the rim part  4035 , the extension  4036  is reinforced. As a result, even if the extension  4036  is thermally expanded or thermally contracted, deformation of the extension  4036  by the thermal stress can be suppressed, and dimensional accuracy of the vehicle seat member  4010  can be ensured. 
     Particularly, in this embodiment, the second framework  4022  having the structure in which the pair of opposed parts  4022   a .  4022   a  opposed with each other continues to each other is embedded in the rim part  4035 , and the first extension part  4036 A of the extension  4036  is formed so as to extend between the opposed parts  4022   a ,  4022   a . In this constitution, since the both sides of the first extension part  4036 A of the extension  4036  are restrained, if the reinforcing portion  4026  is not provided, the extension  4036  including the first extension part  4036 A is deformed particularly easily by thermal expansion and thermal contraction. In this embodiment, by embedding the reinforcing portion  4026  in the first extension part  4036 A, the deformation of the extension  4036  including the first extension part  4036 A can be further effectively suppressed. 
     Moreover, as in this embodiment, if the parts including the first framework  4021  and the second framework  4022  of the frame member  4020  continuously circle around along the outer shape  4 S of the vehicle seat member  4010 , the deformation by the thermal stress is suppressed over the entire circumference of the rim part  4035 . Thus, if the reinforcing portion  4026  is not provided, the extension  4036  formed inside the rim part  4035  is deformed further easily. Even in such a case, in this embodiment, by embedding the reinforcing portion  4026  in the extension  4036  as described above, the deformation of the extension  4036  can be suppressed more effectively. 
     4-4. Method of Manufacturing Vehicle Seat Member  4010   
     The method of manufacturing the vehicle seat member  4010  will be described below by referring to  FIG. 37 . In  FIG. 37 , each step of the method of manufacturing will be described by a schematic sectional view at a position corresponding to a I-I line arrow-view sectional view illustrated in  FIG. 36 . 
     An outline of the method of manufacturing the vehicle seat member  4010  of this embodiment is as follows. As illustrated in  FIG. 37(A) , the frame member  4020  is disposed so as to be located in a cavity  4073  of the molding die  4007  and then, pre-expanded resin particles  4030 A obtained by pre-expanding the expandable resin particles containing the resin and the foaming agent are filled therein. Subsequently, as illustrated in  FIG. 37(B) , the pre-expanded resin particles  4030 A are expanded by supplying steam into the molding die  4007  so as to mold the foamed resin molded body  4030 . After that, as illustrated in  FIG. 37  (C), the foamed resin molded body  4030  is removed from the molding die  4007  together with the frame member  4020  and cooled by releasing heat or the like. 
     The foamed resin molded body  4030  usually has a property of slightly contracting when the remaining heat during the foam molding is released after the molding. On the other hand, the frame member  4020  constituted by a material such as metal is not substantially changed in the dimensions before and after molding of the foamed resin molded body  4030  compared to the foamed resin molded body  4030 . Therefore, if the reinforcing portion  4026  of the frame member  4020  is not embedded in the extension  4036 , as illustrated in  FIG. 38(A) , the foamed resin molded body  4030  is molded by the molding die  4007  made of a first die  4071  and a second die  4072 , and as illustrated in  FIG. 38(B) , for a period of time immediately after the molding until the foamed resin molded body  4030  is removed from the molding die  4007  and the foamed resin molded body  4030  releases heat, the foamed resin molded body  4030  thermally contracts. At this time, since the both sides of the extension  4036  where the frame member  4020  is not present is restrained by the rim part  4035  where the second framework  4022  of the frame member  4020  is present, the compression stress and the tensile stress non-uniformly act as the thermal stress on the extension  4036 , and the extension  4036  is deformed easily so as to be curved upward from the center. 
     In view of these points, in this embodiment, the vehicle seat member  4010  is manufactured as follows. First, the frame member  4020  is prepared. The structure and the material of the frame member  4020  are as described above. Subsequently, as illustrated in  FIG. 37(A) , the first framework  4021  and the second framework  4022  are disposed at positions embedded in the rim part  4035  of the foamed resin molded body  4030  along the outer shape  4 S of the vehicle seat member  4010  in plan view, and the frame member  4020  is disposed in the molding die  4007  so that the reinforcing portion  4026  is disposed at the position embedded in the extension  4036  along the extending direction  4 L in which the extension  4036  of the foamed resin molded body  4030  is extended (placing step). At this time, the frame member  4020  may be disposed in the molding die  4007  by using a robot. 
     As illustrated in  FIG. 37(A) , the molding die  4007  is made of the first die  4071  and the second die  4072  and is constituted so that the cavity  4073  according to the foamed resin molded body  4030  is formed in the molding die  4007  when the first die  4071  and the second die  4072  are clamped. 
     Subsequently, as illustrated in  FIG. 37(A) , the first die  4071  and the second die  4072  in which the frame member  4020  is disposed therein is temporarily clamped (cracking) and then, the pre-expanded resin particles  4030 A obtained by pre-expanding the expandable resin particles containing the resin and the foaming agent are filled and clamped. 
     Subsequently, as illustrated in  FIG. 37(B) , the pre-expanded resin particles  4030 A are secondarily foamed by heating the inside of the cavity  4073  of the molding die  4007  by steam or the like, the gaps among the pre-expanded resin particles  4030 A are filled, and the pre-expanded resin particles  4030 A are integrated by fusing them to each other so that the foamed resin molded body  4030  is molded (molding step). 
     As described above, in the molding die  4007 , the foamed resin molded body  4030  including the rim part  4035  and the extension  4036  can be molded. The molded rim part  4035  has the first framework  4021  and the second framework  4022  of the frame member  4020  embedded and forms the outer shape  4 S of the vehicle seat member  4010 . The molded extension  4036  extends so that the first extension part  4036 A extends between the pair of side parts  4035   c ,  4035   c  of the rim part  4035  and the second extension parts  4036 B,  4036 B extend between the front part  4035   a  and the rear part  4035   b  of the rim part  4035 . The first extension part  4036 A of the extension  4036  has the reinforcing portion  4026  of the frame member  4020  disposed along the extending direction  4 L thereof embedded. 
     Subsequently, the foamed resin molded body  4030  is removed from the molding die  4007 , and the vehicle seat member  4010  of this embodiment in which the foamed resin molded body  4030  and the frame member  4020  are integrated can be obtained. Here, during and after the removal of the foamed resin molded body  4030  from the molding die  4007 , remaining heat during the molding is released, and the foamed resin molded body  4030  contracts. 
     In the embodiment, even if the extension  4036  thermally contracts, since the reinforcing portion  4026  is embedded, deformation of the extension  4036  by the thermal stress can be suppressed. As a result, the vehicle seat member  4010  with high dimensional accuracy can be manufactured. 
     In this embodiment, the frame member  4020  has the second framework  4022 , and the second framework  4022  has the continuous part in which the opposed parts  4022   a  opposed to each other across the space inside the rim part  4035  continue to each other. When the foamed resin molded body  4030  is molded, the extension  4036  is molded so as to have the first extension part  4036 A extending between the opposed parts  4022   a ,  4022   a . Therefore, since the both sides of the first extension part  4036 A of the extension  4036  are restrained by the side parts  4035   c ,  4035   c  of the rim part  4035  in which the opposed parts  4022   a ,  4022   a  of the second framework  4022  of the frame member  4020  are embedded, if the reinforcing portion  4026  of the frame member  4020  is not provided as illustrated in  FIG. 38 , the extension  4036  is deformed easily by the thermal contraction. Particularly since the parts including the first framework  4021  and the second framework  4022  of the frame member  4020  are made to continuously circle around along the outer shape  4 S of the vehicle seat member  4010 , such deformation occurs easily. In this embodiment, since the extension  4036  is molded so that the reinforcing portion  4026  of the frame member  4020  is embedded in the first extension part  4036 A which is one of the extension parts during the molding step, such deformation can be suppressed. 
     Fourth Invention/Second Embodiment 
     The vehicle seat member  4010  according to a second embodiment of the fourth invention and the method of manufacturing the same will be described below by referring to  FIGS. 39 and 40 . A point that the vehicle seat member  4010  according to the second embodiment is different from the vehicle seat member  4010  according to the first embodiment is that, in the second extension parts  4036 B,  4036 B extending in the transverse direction, the reinforcing portions  4026 ,  4026  extending along them are embedded, not in the first extension part  4036 A extending in the longitudinal direction of the outer shape  4 S of the vehicle seat member  4010  in the extension  4036 . The same constitutions as those in the first embodiment are given the same reference numerals and detailed description will be omitted. 
     In this embodiment, by embedding two pieces of the reinforcing portions  4026 ,  4026  in two pieces of the second extension parts  4036 B,  4036 B extending along the short side direction in the extension  4036  extending inside the rim part  4035 , respectively, the extension  4036  is reinforced. As a result, even if the extension  4036  is thermally expanded or thermally contracted, deformation of the extension  4036  by the thermal stress can be suppressed, and dimensional accuracy of the vehicle seat member  4010  can be ensured. 
     In this embodiment, the frame member  4020  has a structure in which the first framework  4021  and a part  4022   b  along the rear edge  4   s B in the second framework  4022  opposed with the first framework  4021  continue to each other. The first framework  4021  and the part  4022   b  along the rear edge  4   s B in the second framework  4022  are embedded in the rim part  4035 , and the second extension parts  4036 B,  4036 B of the extension  4036  are formed so as to extend between the first framework  4021  and the part  4022   b  along the rear edge  4   s B in the second framework  4022 . In this constitution, since the both sides of the second extension parts  4036 B,  4036 B of the extension  4036  are restrained, respectively, if the reinforcing portion  4026  is not provided, the extension  4036  including the second extension parts  4036 B,  4036 B is deformed particularly easily by thermal expansion and thermal contraction. In this embodiment, by embedding the reinforcing portions  4026 ,  4026  in the second extension parts  4036 B,  4036 B, the deformation of the extension  4036  including the second extension parts  4036 B,  4036 B can be effectively suppressed. 
     Manufacture of the vehicle seat member  4010  according to the second embodiment can be performed by the procedure similar to the first embodiment. 
     First, the frame member  4020  is disposed in the molding die so that the first framework  4021  and the second framework  4022  are disposed at positions embedded in the rim part  4035  of the foamed resin molded body  4030  along the outer shape  4 S of the vehicle seat member  4010  in plan view, and the reinforcing portions  4026 ,  4026  are disposed at positions embedded in the second extension parts  4036 B,  4036 B in the extension  4036  of the foamed resin molded body  4030  (placing step). Here, the molding die is made of the first die and the second die and is constituted such that when the first die and the second die are clamped, a cavity according to the foamed resin molded body  4030  is formed in the molding die. 
     Subsequently, after the first die and the second die in which the frame member  4020  is disposed is temporarily clamped (cracking), the pre-expanded resin particles obtained by pre-expanding the expandable resin particles containing the resin and the foaming agent are filled and clamped. 
     Subsequently, the pre-expanded resin particles are secondarily foamed by heating the inside of the cavity of the molding die by steam or the like, gaps among the pre-expanded resin particles are filled, and the pre-expanded resin particles are integrated by fusing them to each other so that the foamed resin molded body  4030  is molded (molding step). 
     As a result, the foamed resin molded body  4030  including the rim part  4035  and the extension  4036  can be molded in the molding die. The molded rim part  4035  has the first framework  4021  and the second framework  4022  in the frame member  4020  embedded therein and forms the outer shape  4 S of the vehicle seat member  4010 . In the molded extension  4036 , the first extension part  4036 A extends between the pair of side parts  4035   c ,  4035   c  of the rim part  4035 , and the second extension parts  4036 B,  4036 B extend between the front part  4035   a  and the rear part  4035   b  of the rim part  4035 . The second extension parts  4036 B,  4036 B of the extension  4036  have the reinforcing portions  4026 ,  4026  of the frame member  4020  disposed along the extending directions thereof embedded. 
     Subsequently, the foamed resin molded body  4030  is removed from the molding die, and the vehicle seat member  4010  of this embodiment in which the foamed resin molded body  4030  and the frame member  4020  are integrated can be obtained. Here, during and after the removal of the foamed resin molded body  4030  from the molding die, remaining heat during the molding is released, and the foamed resin molded body  4030  contracts. 
     In the embodiment, even if the extension  4036  thermally contracts, since the reinforcing portion  4026  is embedded in the second extension parts  4036 B,  4036 B, deformation of the extension  4036  by the thermal stress can be suppressed. As a result, the vehicle seat member  4010  with high dimensional accuracy can be manufactured 
     In this embodiment, the frame member  4020  is formed so as to have a continuing structure in which the first framework  4021  and the part  4022   b  along the rear edge  4   s B in the second framework  4022  which are a pair of opposed parts continue to each other. And the frame member  4020  having this continuing structure is embedded in the rim part  4035 , and the second extension parts  4036 B,  4036 B of the extension  4036  are formed so as to extend between the first framework  4021  and the part  4022   b  along the rear edge  4   s B in the second framework  4022 , respectively. Thus, one ends of the second extension parts  4036 B,  4036 B of the extension  4036  are restrained by the front part  4035   a  of the rim part  4035  in which the first framework  4021  of the frame member  4020  is embedded, and the other ends of the second extension parts  4036 B,  4036 B of the extension  4036  are restrained by the rear part  4035   b  of the rim part  4035  in which the part  4022   b  along the rear edge  4   s B in the second framework  4022  of the frame member  4020  is embedded and thus, if the reinforcing portions  4026 ,  4026  of the frame member  4020  are not provided, the extension  4036  is deformed easily by thermal contraction. Moreover, in this embodiment, the parts including the first framework  4021  and the second framework  4022  of the frame member  4020  are made to continuously circle around along the outer shape  4 S of the vehicle seat member  4010  and thus, such deformation can occur particularly easily. In this embodiment, by molding the extension  4036  so that the reinforcing portions  4026 ,  4026  of the frame member  4020  are embedded in the second extension parts  4036 B,  4036 B, one of the extension parts, during the molding step, respectively, such deformation can be suppressed. 
     Some embodiments of the fourth invention have been described in detail, but the fourth invention is not limited to the aforementioned embodiments but is capable of various design changes within a range not departing from the scope of the fourth invention described in “Solution to Problem”. 
     EXAMPLES 
     &lt;First Invention&gt; 
     First Invention Example 1 
     The vehicle seat member  1  of the first embodiment of the first invention illustrated in  FIGS. 1 to 7  was manufactured by in-mold foam molding. 
     The used molding die  70  was formed so that dimensions of a part of the foamed resin molded body  100  of the vehicle seat member  1  to be manufactured had a width in the longitudinal direction of 1260 mm, a width in the transverse direction of 550 mm, and a thickness of 160 mm. 
     For the first framework  250  and the second framework  260  of the frame member  200 , an iron % ire (SWM-B) with a diameter of 4.5 mm was used. 
     The gaps  101 ,  102  formed in the front part  120  (see  FIG. 2 ) of the foamed resin molded body  100  were grooves each having a width of 10 mm and a length of 200 mm and were formed as the grooves each having such a depth that the second framework right part  201  or the second framework left part  202  was located on bottom surfaces thereof. 
     The gaps  101 ,  102  formed in the rear part  130  (see  FIG. 2 ) of the foamed resin molded body  100  were grooves each having a width of 10 mm and a length of 100 mm and were formed as the grooves having such a depth that the second framework right part  201  or the second framework left part  202  are located on bottom surfaces thereof. 
     The second framework right part  201  was disposed so as to extend through the centers of the gaps  101 ,  101  in the width direction. 
     Similarly, the second framework left part  202  was disposed so as to extend through the centers of the gaps  102 ,  102  in the width direction. 
     The foamed resin molded body  100  was molded by a composite resin containing the polystyrene-based resin and the polyolefin-based resin with the expansion ratio of 30 times. 
     The manufacture of the vehicle seat member  1  was performed by the procedure described in the description related to the first embodiment of the first invention. The formation of the gaps  101 ,  101 ,  102 ,  102  was performed at the same time as the molding step of the foamed resin molded body  100  by the in-mold foam molding by the procedure described by referring to  FIG. 7 . 
     After the molding step, the molding die  70  was removed, and cooling by releasing heat was sufficiently performed to a room temperature. 
     After the cooling, the first extension part  182 A of the extension  182  of the foamed resin molded body  100  had its center part curved upward and protruded (a case of a Comparative Example 1 which will be described later is illustrated in  FIG. 15(B) ). How much it protruded (a maximum deformation amount) from a position of the center part of the first extension part  182 A assuming that the first extension part  182 A is not curved at all was measured, and the maximum deformation amount was 3.2 mm. 
     An allowable maximum deformation amount of the vehicle seat member  1  is 6 mm. The maximum deformation amount (3.2 mm) of the vehicle seat member  1  of the Example 1 of the first invention was within an allowable range. 
     First Invention Example 2 
     The vehicle seat member  1  of the first embodiment of the first invention illustrated in  FIGS. 1 to 7  was manufactured by in-mold foam molding. 
     The vehicle seat member  1  of the Example 2 of the first invention was manufactured under the conditions similar to those of the Example 1 of the first invention except that the second framework right part  201  was disposed so as to extend through the innermost side in the width direction of the gaps  101 ,  101 , and the second framework left part  202  was disposed so as to extend through the innermost side in the width direction of the gaps  102 ,  102 . 
     The maximum deformation amount of the vehicle seat member  1  of the Example 2 of the first invention was 3.0 mm and was within the allowable range. 
     First Invention Example 3 
     The vehicle seat member  1  of the third embodiment of the first invention illustrated in  FIGS. 12 to 14  was manufactured by in-mold foam molding. 
     As the four tubular bodies  500 , a tubular body having an inner diameter of 10 mm and a length of 40 mm was used. 
     The used molding die  80  was formed so that dimensions of a part of the foamed resin molded body  100  of the vehicle seat member  1  to be manufactured had a width in the longitudinal direction of 1260 mm, a width in the transverse direction of 550 mm, and a thickness of 160 mm. 
     As the foamed resin molded body  100  and the frame member  200 , those similar to the Example 1 of the first invention were used. 
     The second framework first corner part  205 , the second framework second corner part  206 , the second framework third corner part  207 , and the second framework fourth corner part  208  were disposed so as to go through the center of the internal space of the tubular body  500 , respectively. 
     The manufacture of the vehicle seat member  1  was performed by the procedure described in the description related to the third embodiment of the first invention. The formation of the gaps  108  to  111  was performed at the same time as the molding step of the foamed resin molded body  100  by the in-mold foam molding by the procedure described by referring to  FIG. 14 . 
     After the molding step, the molding die  80  was removed, and cooling by releasing heat was sufficiently performed to a room temperature. 
     The maximum deformation amount of the vehicle seat member  1  of the Example 3 of the first invention measured similarly to the Example 1 of the first invention was 5.1 mm and was within the allowable range. 
     First Invention Comparative Example 1 
     The vehicle seat member of the Comparative Example 1 of the first invention was manufactured with conditions and procedures similar to those in the Example 1 of the first invention except that the gaps  101 ,  101 ,  102 ,  102  are not formed. 
     The maximum deformation amount of the vehicle seat member  1  of the Comparative Example 1 of the first invention measured similarly to the Example 1 of the first invention was 8.5 mm and exceeded the allowable range (6 mm). 
     First Invention Comparative Example 2 
     Instead of the gaps  101 ,  101  extending along the second framework right part  201  in the Example 1 of the first invention, a groove with a width of 10 mm and a length of 100 mm extending in the direction perpendicular to the second framework right part  201  and formed so that the second framework right part  201  passed through the center in the extending direction and having a depth in which the second framework right part  201  was located on a bottom surface thereof was formed on the bottom surface  140  of the foamed resin molded body  100 . 
     Furthermore, instead of the gaps  102 ,  102  extending along the second framework left part  202  in the Example 1 of the first invention, a groove with a width of 10 mm and a length of 100 mm extending in the direction perpendicular to the second framework left part  202  and formed so that the second framework left part  202  passed through the center in the extending direction and having a depth in which the second framework left part  202  was located on a bottom surface thereof was formed on the bottom surface  140  of the foamed resin molded body  100 . 
     The vehicle seat member of the Comparative Example 2 of the first invention was manufactured with the conditions and procedures similar to those in the Example 1 of the first invention except the aforementioned points. 
     The maximum deformation amount of the vehicle seat member of the Comparative Example 2 of the first invention measured similarly to the Example 1 of the first invention was 7.5 mm and exceeded the allowable range (6 mm). 
     &lt;Third Invention&gt; 
     Third Invention Example 1 
     The vehicle seat member  3010  of the first embodiment of the third invention illustrated in  FIGS. 24 to 29  was manufactured by in-mold foam molding. 
     The used molding die  3007  was formed so that dimensions of a part of the foamed resin molded body  3030  of the vehicle seat member  3010  to be manufactured had a width in the longitudinal direction of 1260 mm, a width in the transverse direction of 550 mm, and a thickness of 160 mm. 
     For the first framework  3021  and the second framework  3022  of the frame member  3020 , an iron wire (SWM-B) with a diameter of 4.5 mm was used. 
     The foamed resin molded body  3030  was molded by a composite resin containing the polystyrene-based resin and the polyolefin-based resin. 
     In the foamed resin molded body  3030 , the first extension part  3036 A of the extension  3036  and the connecting part  3035 ′ connected to the first extension part  3036 A in the rim part  3035  were molded by a foamed resin having the expansion ratio of 20 times and the maximum point stress by bending measured under the aforementioned conditions of 592 kPa. 
     On the other hand, in the foamed resin molded body  3030 , the first extension part  3036 A of the extension  3036  and the part other than the connecting part  3035 ′ connected to the first extension part  3036 A in the rim part  3035  (including the not-connecting part  3036 ″ of the rim part  3035 ) were molded by a foamed resin having the expansion ratio of 30 times and the maximum point stress by bending measured under the aforementioned conditions of 354 kPa. 
     The manufacture of the vehicle seat member  3010  was performed by the procedure described in the description related to the first embodiment of the third invention. 
     After the molding step, the molding die  3007  was removed, and radiational cooling was sufficiently performed to a room temperature. 
     After the cooling, the first extension part  3036 A of the extension  3036  in the foamed resin molded body  3030  had its center part curved upward and protruded (a case of the Comparative Example 1 of the third invention which will be described later is illustrated in  FIG. 30(B) ). How much it protruded (the maximum deformation amount) from a position of the center part of the first extension part  3036 A assuming that the first extension part  3036 A is not curved at all was measured, and the maximum deformation amount was 6.0 mm. 
     The allowable maximum deformation amount of the vehicle seat member  3010  is 6 mm. The maximum deformation amount (6.0 mm) of the vehicle seat member  3010  of the Example 1 of the third invention was within the allowable range. 
     Third Invention Example 2 
     The vehicle seat member  1  of the first embodiment of the third invention illustrated in  FIGS. 24 to 29  was manufactured by in-mold foam molding. 
     The vehicle seat member  1  of the Example 2 of the third invention was manufactured by the conditions similar to those in the Example 1 of the third invention except that in the foamed resin molded body  3030 , the first extension part  3036 A of the extension  3036  and the connecting part  3035 ′ connected to the first extension part  3036 A in the rim part  3035  were molded by a foamed resin having the expansion ratio of 15 times and the maximum point stress by bending measured under the aforementioned conditions of 774 kPa. 
     The maximum deformation amount of the vehicle seat member  1  of the Example 2 of the third invention was 5.1 mm and was within the allowable range. 
     Third Invention Example 3 
     The vehicle seat member  1  of the first embodiment of the third invention illustrated in  FIGS. 24 to 29  was manufactured by in-mold foam molding. 
     The vehicle seat member  1  of the Example 3 of the third invention was manufactured by the conditions similar to those in the Example 1 of the third invention except that in the foamed resin molded body  3030 , the first extension part  3036 A of the extension  3036  and the connecting part  3035 ′ connected to the first extension part  3036 A in the rim part  3035  were molded by a foamed resin having the expansion ratio of 10 times and the maximum point stress by bending measured under the aforementioned conditions of 873 kPa. 
     The maximum deformation amount of the vehicle seat member  1  of the Example 3 of the third invention was 3.9 mm and was within the allowable range. 
     Third Invention Example 4 
     The vehicle seat member  1  of the first embodiment of the third invention illustrated in  FIGS. 24 to 29  was manufactured by in-mold foam molding. 
     The vehicle seat member  1  of the Example 4 of the third invention was manufactured by the conditions similar to those in the Example 1 of the third invention except that in the foamed resin molded body  3030 , the first extension part  3036 A of the extension  3036  and the connecting part  3035 ′ connected to the first extension part  3036 A in the rim part  3035  were molded by a foamed resin having the expansion ratio of 5 times and the maximum point stress by bending measured under the aforementioned conditions of 1008 kPa. 
     The maximum deformation amount of the vehicle seat member  1  of the Example 4 of the third invention was 2.8 mm and was within the allowable range. 
     Third Invention Comparative Example 1 
     The vehicle seat member of the Comparative Example 1 of the third invention was manufactured by the conditions similar to those in the Example 1 of the third invention except that the entire foamed resin molded body  3030  was molded by the foamed resin having the expansion ratio of 30 times and the maximum point stress by bending measured under the aforementioned conditions of 354 kPa. 
     The maximum deformation amount of the vehicle seat member of the Comparative Example 1 of the third invention was 8.5 mm and largely exceeded the allowable maximum deformation amount of 6 mm. 
     REFERENCE SIGNS LIST 
     &lt;First Invention&gt; 
       1  vehicle seat member,  100  foamed resin molded body.  101 ,  102 ,  105 ,  106 ,  108 ,  109 ,  110 ,  111  gap,  200  frame member.  250  first framework,  260  second framework,  201  second framework right part,  202  second framework left part,  204  second framework rear part,  205  second framework first corner part,  206  second framework second corner part,  207  second framework third corner part,  208  second framework fourth corner part,  400  outer shape of vehicle seat member,  401  right edge,  402  left edge,  403  front edge,  404  rear edge,  405  first corner,  406  second corner,  407  third corner,  408  fourth corner,  500  tubular body.  501  inner peripheral surface of tubular body,  502  outer peripheral surface of tubular body,  70 ,  80  molding die 
     &lt;Second Invention&gt; 
       2001 : vehicle seat,  2007 : molding die,  2010 : vehicle seat member,  2020 : frame member,  2022 : framework,  2022 - 1 : framework first section,  2201 : first part,  2202 : second part.  2201   a : one end of first part,  2202   a : one end of second part,  2201   b : another end of first part,  2202   b : another end of second part,  2201   c : side of the other end of first part,  2202   c : side of the other end of second part,  2023 A: first plate-shaped member,  2023 B: second plate-shaped member,  2024 A: first locking fixture,  2024 B: second locking fixture,  2241 A,  2241 B: base.  2242 A.  2242 B: column portion,  2243 A,  2243 B: locking portion,  2030 : foamed resin molded body,  2035 : rim part,  2036 : extension 
     Third Embodiment 
       3001 : vehicle seat,  3007 : molding die,  3010 : vehicle seat member,  3020 : frame member,  3021 : first framework,  3022 : second framework,  3030 : foamed resin molded body,  3035 : rim part.  3036 : extension.  3036 A: first extension part,  3036 B: second extension part 
     &lt;Fourth Invention&gt; 
       4001 : vehicle seat,  4007 : molding die,  4010 : vehicle seat member,  4020 : frame member,  4021 : first framework,  4022 : second framework,  4026 : reinforcing portion,  4030 : foamed resin molded body,  4035 : rim part,  4036 : extension,  4036 A: first extension part,  4036 B: second extension part 
     All the publications, patents, and patent applications cited in the description are incorporated in the description as they are by reference.