Body structure of motor vehicle

Abstract: A body structure of a motor vehicle having an inner section and an outer section is disclosed. The vehicle body structure comprises an outer panel structure and an inner closed section structure. The outer panel structure forms the outer section of the body structure. The inner closed section structure is disposed along an inner side configuration of the outer panel structure and attached to the outer panel structure. The inner closed section structure has a sectional configuration that changes in accordance with changes in the inner side configuration of the outer panel structure and has a closed section that is made of a single member. The outer panel structure has a part that functions as the inner section of the body structure.

Description: BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a body structure of a motor vehicle, and in particular to a body structure of a motor vehicle which is provided with a structure manufactured by a tube hydraulic forming method or the like. Description of the Related Art It is conventionally known that a hollow structure is obtained by supplying high-pressure fluid such as oil into a raw tube and deforming the tube into a predetermined configuration by using a tube hydraulic forming method. Japanese Patent Unexamined Publication No. 8-337182 discloses a body structure of a motor vehicle which is provided with two hollow structures formed by a tube hydraulic forming method. In the vehicle body structure, the two hollow structures are mutually connected along a partial area of its longitudinal direction. Japanese Patent Unexamined Publication No. 9-150752 discloses a vehicle body frame structure that comprises a plurality of hoop-shaped members. The hoop-shaped members are obtained by extruding raw aluminum alloy into hollow members and bending the hollow members. Then, the body frame structure is formed by welding the members to make a doorframe and the like. U.S. Patent No. 5,269,585 discloses a motor vehicle body, which is provided with extruded hollow profiles or structures. Similar examples of such conventional art are also disclosed in Japanese Patent Unexamined Publications No. 10-95364, No. 10-95365, No. 9-30345, No. 10-138950 and No. 8-192238. JP 10 218017 A discloses a vehicle body structure including a second reinforcement within the centre pillar. The second reinforcement is an extruded sectional reinforcement and the upper portion of the reinforcement is connected with a brace. The section configuration of the reinforcement is not uniform. DE 195 18 946 A1 discloses a vehicle body structure including a reinforcement member within a front pillar. The reinforcement member is made out of an extruded hollow sectional light metal member with a uniform section. US 4,911,553 discloses a vehicle body structure including a door sill between an "A" pillar and a "B" pillar. The door sill is provided with a steel sill tube which is mounted to the door sill by a support member, and the front end of the tube is connected to the A pillar by an inner hinge member and the rear end of the tube is connected to the B pillar by a brace assembly and a L-shaped brace. US 4,355,843 discloses a vehicle body structure including a metallic pipe within the space of the front pillar. Since a hollow structure is formed by uniformly pressurizing a raw tube from its inner side by using a tube hydraulic forming method, the hollow structure can be made from materials such as ultra-high-strength steel. The ultra-high-strength steel has greater tensile strength than material of the conventional structure formed by press molding. As a result, since the hollow structure has greater proof stress and therefore has great strength, the weight of the vehicle body can be decreased. Accordingly, as mentioned above, many vehicle body structures provided with hollow structures formed by the tube hydraulic forming method have been proposed. However, such hollow structures formed by the tube hydraulic forming method are not enough applied to the vehicle body structure, and various applications of the hollow structures to the vehicle body structure therefore have been demanded. Further, the application of a hollow structure or a closed section structure made by other than the tube hydraulic forming method to a vehicle body structure also has been demanded. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a body structure of a motor vehicle which is both light in weight and increased in rigidity or stiffness. The above object is achieved according to the features of claim 1 Embodiments of the invention according to claim 1 are defined in dependent claims 2 to 9. Embodiments of the present invention will be apparent from the following description by taking reference with accompanying drawings employed for preferred embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings: Figure 1 is an overall perspective view of a body structure of a motor vehicle according to a first embodiment of the present invention; Figure 2 is an exploded perspective view of components of the first embodiment of Figure 1; Figure 3 is an enlarged perspective view of a portion designated as G in Figure 2; Figure 4 is an enlarged perspective view of a portion designated as E in Figure 2; Figure 5 is a sectional view of the first embodiment taken along line V-V in Figure 1; Figure 6 is a sectional view of the first embodiment taken along line VI-VI in Figure 1; Figure 7 is a sectional view of the first embodiment taken along line VII-VII in Figure 1; Figure 8 is a sectional view of the first embodiment taken along line VIII-VIII in Figure 1; Figure 9 is a sectional view of the first embodiment taken along line IX-IX in Figure 1; Figure 10 is a sectional view of the first embodiment taken along line X-X in Figure 1; Figure 11 is a partial perspective view of a body structure of a motor vehicle according to a second embodiment of the present invention; Figure 12 is a sectional view of the second embodiment taken along line XII-XII in Figure 11; Figure 13 is an enlarged perspective view of a portion designated as J in Figure 12; Figure 14 is an enlarged sectional view of a portion designated as J in Figure 12; Figure 15 is a sectional view of the second embodiment taken along line XV-XV in Figure 14; Figure 16 is a sectional view of the second embodiment taken along line XVI-XVI in Figure 14; and Figure 17 is an enlarged sectional view of a portion designated as K in Figure 12. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the preferred embodiments of the present invention will be explained with reference to the drawings. A first embodiment of the present invention will be explained with reference to Figures 1 through 8. Referring to Figures 1 and 2, a reference numeral 1 designates a side body structure of a motor vehicle which is provided with a roof rail section 2, a center pillar section 4 and a side sill section 6. The vehicle side body structure 1 comprises a side frame outer panel 8, which is an outer panel structure forming an outer section of the vehicle side body structure, and an inner closed section structure 10. The inner closed section structure 10 is disposed along the side frame outer panel 8 in a passenger compartment side and forms a part of an inner section of the vehicle side body structure 1. The vehicle side body structure 1 further comprises a plurality of inner bands 12 which are used to attach the inner closed section structure 10 to the side frame outer panel 8. The side frame outer panel 8 forming the outer panel structure is manufactured by press molding. Front doors 7 and rear doors 9 are respectively attached to the side frame out panel 8 of the vehicle side body structure 1. Referring to Figure 2, the inner closed section structure 10 is composed of a roof rail reinforcement 22, a center pillar reinforcement 24 and a side sill reinforcement 26. The sectional configurations of the inner closed section structure 10 change in accordance with changes in the inner side configurations of the roof rail section 2, the center pillar section 4 and the side sill section 6 of the side frame outer panel 8. Referring to Figure 3, an upper end 24a of the center pillar reinforcement 24 is inserted into an opening 22a of the roof rail reinforcement 22 and is connected with a connection portion 22b of the roof rail reinforcement 22 by welding or the like. Thus, the upper end 24a of the center pillar reinforcement 24 is connected with the roof rail reinforcement 22. Referring to Figure 4, a lower end 24b of the center pillar reinforcement 24 is inserted into an opening 26a of the side sill reinforcement 26 and is connected with a connection portion 26b of the side sill reinforcement 26 by welding or the like. Thus, the lower end 24b of the center pillar reinforcement 24 is connected with the side sill reinforcement 26. The inner closed section structure 10 is formed in the following manner. First, the roof rail reinforcement 22, the center pillar reinforcement 24 and the side sill reinforcement 26 are respectively manufactured by supplying high-pressure fluid such as oil into raw tubes and then deforming the tubes into predetermined configurations under predetermined conditions of the tube hydraulic forming method. Thereafter, as mentioned above, the upper end 24a of the center pillar reinforcement 24 is connected with the roof rail reinforcement 22, and the lower end 24b of the center pillar reinforcement 24 is connected with the side sill reinforcement 26. As a result, the integrally formed inner closed section structure 10 is obtained. Next, respective sectional configurations of the vehicle side body structure 1 will be explained with references to Figures 5 through 10. Referring to Figure 5, in an area of the roof rail reinforcement 2 of the side body structure 1 in which the inner band 12 is provided, a roof rail outer 28, which is a part of the side frame outer panel 28, is disposed at an outer side. The roof rail reinforcement 22 of the inner closed section structure 10 is disposed at the passenger compartment side of the roof rail outer 28, and the inner band 12 is disposed at the passenger compartment side of the roof rail reinforcement 22. A flange 28a of the roof rail outer 28 and a flange 12a of the inner band 12 are mutually connected. A part 22c of the surface of the roof rail reinforcement 22 located at an inner side thereof is connected with the inner band 12 by spot welding. A seal member 36 is attached to the flanges 12a and 28a to contact the door 9 so that an opening for the door 9 is sealed. Referring to Figure 6, in an area of the roof rail reinforcement 2 of the side body structure 1 in which the inner band 12 is not provided, the roof rail outer 28, which is a part of the side frame outer panel 8, is disposed at an outer side. The roof rail reinforcement 22 of the inner closed section structure 10 is disposed at the passenger compartment side of the roof rail outer 28. The roof rail outer 28 is provided with the flange 28a to which the seal member 36 is attached. The seal member 36 contacts the door 9 so that the opening for the door 9 is sealed. According to the first embodiment of the present invention, the vehicle side body structure 1 does not need to be provided with an inner section or a roof rail inner of the side body structure, which components need to be provided for the conventional side body structure, since the inner closed section structure 10 of the first embodiment functions, in the area in which the inner band 12 is not provided, as a part of the inner section or the roof rail inner. Referring to Figure 7, in an area of the center pillar section 4 of the side body structure 1 in which the inner band 12 is provided, a center pillar outer 30, which is a part of the side frame outer panel 8, is disposed at an outer side. The center pillar reinforcement 24 of the inner closed section structure 10 is disposed at the passenger compartment side of the center pillar outer 30, and the inner band 12 is disposed at the passenger compartment side of the center pillar reinforcement 24. A flange 30a of the center pillar outer 30 and a flange 12a of the inner band 12 are mutually connected. A part 24c of the surface of the center pillar reinforcement 24 located at an inner side thereof is connected with the inner band 12 by spot welding. The seal members 36 are attached to the flanges 12a and 30a to contact the doors 7 and 9 so that the openings for the doors 7 and 9 are sealed. Referring to Figure 8, in an area of the center pillar section 4 of the side body structure 1 in which the inner band 12 is not provided, the center pillar outer 30, which is a part of the side frame outer panel 8, is disposed at an outer side. The center pillar reinforcement 24 of the inner closed section structure 10 is disposed at the passenger compartment side of the center pillar outer 30. A flange 30a of the center pillar outer 30 and a flange 12a of the inner band 12 are mutually connected. A part 24c of the surface of the center pillar reinforcement 24 located at an inner side thereof is connected with the inner band 12 by spot welding. The seal members 36 are attached to the flanges 12a and 30a to contact the doors 7 and 9 so that the openings of the doors 7 and 9 are sealed. The center pillar outer 30 is provided with the flanges 30a to which the seal members 36 are respectively attached. The seal members 36 contact the doors 7 and 9 so that the opening for the doors 7 and 9 are sealed. According to the first embodiment of the present invention, the side body structure 1 does not need to be provided with an inner section or a center pillar inner of the side body structure, which components need to be provided for the conventional side body structure. This is because the inner closed section structure 10 functions, in the area in which the inner band 12 is not provided, as a part of the inner section or the center pillar inner. Referring to Figure 9, in an area of the side sill section 6 of the side body structure 1 in which the inner band 12 is provided, a side sill outer 32, which is a part of the side frame outer panel 8, is disposed at an outer side. The side sill reinforcement 26 of the inner closed section structure 10 is disposed at the passenger compartment side of the side sill outer 32, and the inner band 12 is disposed at the passenger compartment side of the side sill reinforcement 26. Flanges 32a of the side sill outer 32 and the flanges 12a of the inner band 12 are mutually connected. A part 26c of the surface of the side sill reinforcement 26 located at an inner side thereof is connected with the inner band 12 by spot welding. In the side sill section 6, a plurality of flat plate node members 34 are disposed along the side sill 6 between the side sill outer 32 and the side sill reinforcement 26 so as to increase the rigidity of the side sill section 6 and to prevent the distortion of the side sill section 6. Referring to Figure 10, in an area of the side sill section 6 of the side body structure 1 in which the inner band 12 is not provided, the side sill outer 32, which is a part of the side frame outer panel 8, is disposed at an outer side. The side sill reinforcement 26 of the inner closed section structure 10 is disposed at the passenger compartment side of the side sill outer 32. The first embodiment of the present invention has the following advantageous effects. The vehicle side body structure 1 does not need to be provided with the inner section, namely the roof rail inner, the center pillar inner and/or the side sill inner, which components need to be provided for the conventional side body structure. This is because the inner closed section structure 10 functions, in the area in which the inner band 12 is not provided, as a part of the inner section. Since the side frame outer panel 8 forming the outer panel structure is combined with the inner closed section structure 10 to obtain the vehicle side body structure 1, the rigidity of the vehicle side body structure 1 is increased. Since the inner closed section structure 10 is made of a single member, as compared with the conventional side body structure, the amount of material and numbers of components are both decreased and thus the weight of the vehicle side body structure 1 is lightened. Since the inner closed section structure 10 is manufactured by the tube hydraulic forming method, the rigidity or stiffness of the side body structure 1 is increased and the weight of the side body structure 1 is decreased, in comparison with the conventional side body structure manufactured by the press molding. Since the sectional configurations of the inner closed section structure 10 change in accordance with changes in the inner side configurations of the roof rail section 2, the center pillar section 4 and the side sill section 6 of the side frame outer panel 8, the number of the components can be decreased. Since the outer panel structure 8 forming the side frame outer panel 8 is disposed at the outer side of the inner closed section structure 10, the flanges of the side frame outer panel 8 can be effectively utilized as the connection portions with the seal portions and the glasses. Next, a second embodiment of the present invention will be explained with reference to Figures 11 through 17. Referring to Figures 11 and 12, a body structure 40 of a motor vehicle comprises a roof rail section 2, a center pillar section 4 and a side sill section 6. In the second embodiment, the vehicle body structure 1 further comprises a roof section 42 and a floor section 44. The vehicle body structure 40 is provided with an outer panel structure 50 (only one side thereof is shown in Figure 11) forming an outer section of the body structure 40. The outer panel structure 50 is composed of a side frame outer panel 8, a roof rail outer panel 52 and a floor outer panel 54. These panels 8, 52 and 54 are connected to each other by flanges to form an annular structure. The vehicle body structure 40 is further provided with an inner closed section structure 56 which is composed of a roof reinforcement 58, a roof rail reinforcement 60, a center pillar reinforcement 62, a side sill reinforcement 64 and a floor cross member 66. These reinforcements 58, 60, 62 and 64 and the member 66 are connected to each other by welding or the like to form an integral structure. The vehicle body structure 40 is further provided with a roof rail inner 68, a center pillar inner 70 and a side sill inner 72 but is not provided with a roof rail inner panel and a floor inner panel. More specifically, the side frame outer panel 8, the roof rail outer panel 52 and the floor outer panel 54 of the outer panel structure 50 are respectively manufactured by press molding like conventional outer panels. The outer panels 8, 52 and 54 of the outer panel structure 50 are connected to each other through flanges 8a, 52a and 54a by welding or the like to form an integral structure (see Figures 14 and 17). The roof reinforcement 58, the roof rail reinforcement 60, the center pillar reinforcement 62, the side sill reinforcement 64 and the floor cross member 66 of the inner closed section structure 56 are respectively manufactured by the above-mentioned tube hydraulic forming method. Namely, at first, high-pressure fluid such as oil is supplied into the reinforcements 58, 60, 62 and 64 and the member 66 under predetermined conditions of the tube hydraulic forming method. Thereafter, the reinforcements 58, 60, 62 and 64 and the member 66 are respectively deformed into predetermined configurations and then connected each other. As a result, the integral inner closed section structure 56 is obtained. The sectional configurations of the inner closed section structure 56 change in accordance with changes in the inner side configurations of the roof rail section 2, the center pillar section 4 and the side sill section 6 of the outer panel structure 50. Referring to Figures 12 and 14, both ends of the roof reinforcement 58 are respectively connected at connecting portions 74 with upper ends of the center pillar reinforcements 62. Referring to Figures 12 and 17, both ends of the cross member 66 are respectively connected at connecting portions 76 with lower ends of the center pillar reinforcements 62. Referring to Figures 13 and 15, the center pillar reinforcement 62 is disposed at an inner side of the roof rail reinforcement 60 so as to intersect vertically the roof rail reinforcement 60. A part 60a of the inner side surface of the roof rail reinforcement 60 is connected by spot welding with a part 62a of the outer side surface of the intersected portion of the center pillar reinforcement 62. Further, a part 62b of the inner side surface of the center pillar reinforcement 62 is connected by spot welding with the roof rail inner 68. Referring to Figures 13 and 17, the side sill reinforcement 64 is disposed at an inner side of the lower end of the center pillar reinforcement 62 so as to intersect vertically the center pillar reinforcement 62. A part 62b of the inner side surface of the center pillar reinforcement 62 is connected by spot welding with a part 64a of the outer side surface of the intersected portion of the side sill reinforcement 64. Referring to Figure 16, the center portion of the center pillar reinforcement 62 has a sectional configuration including a wavy form 62c. As mentioned above, in the second embodiment, the vehicle body structure 40 is provided with the roof rail inner 68, the center pillar inner 70 and the side sill inner 72 but is not provided with the roof rail inner panel and the floor inner panel. However, the second embodiment is not limited to the above-mentioned structure. Namely, in the second embodiment, the vehicle body structure 40 may not be provided with any one of the above components, namely, the roof rail inner 68, the center pillar inner 70, the side sill inner 72, the roof rail inner panel and the floor inner panel. Further, in the second embodiment, the vehicle body structure 40 may not be provided with predetermined components taken from the components 68, 70, 72, the roof rail inner panel and the floor inner panel. The second embodiment of the present invention has the following advantageous effects. The inner closed section structure 56 function as the inner section of the vehicle body structure 40. More specifically, the roof reinforcement 58 and the floor cross member 66 of the inner closed section structure 56 respectively function as the roof inner panel in the roof section 42 and the floor inner panel in the floor section 44 of the vehicle body structure 40. As a result, for example, the roof inner panel and the floor inner panel that are required in the conventional body structure are not required in the vehicle body structure 40 of the second embodiment. Since the outer panel structure 50 is combined with the inner closed section structure 56 to obtain the vehicle body structure 40, the rigidity of the vehicle body structure 40 is increased. Since the inner closed section structure 56 is an annular structure, the rigidity of the body structure 50 against a load acting from the side direction of the vehicle is greatly increased. Since the inner closed section structure 56 is manufactured by the tube hydraulic forming method, the rigidity of the body structure 40 is increased and the weight of the body structure 40 is decreased in comparison with the conventional body structure manufactured by the press molding. Since the sectional configurations of the inner closed section structure 56 change in accordance with changes in the inner side configurations of the roof rail section 2, the center pillar section 4 and the side sill section 6 of the outer panel structure 50, the number of the components can be decreased. Since the outer panel structure 50 such as the side frame outer panel 8 or the like is disposed at the outer side of the inner closed section structure 56, the flanges of the side frame outer panel 8 or the like forming the outer panel structure 50 can be effectively utilized as the connection portions with the seal portions and the glasses. Although the present invention has been explained with reference to specific, preferred embodiments, one of ordinary skill in the art will recognize that modifications and improvements can be made while remaining within the scope of the present invention which is determined solely by appended claims.

Claims: A body structure of a motor vehicle having an inner section (10) and an outer section (8) comprising: an outer panel structure (8) forming the outer section of the body structure (1), said outer panel structure (8) being an integral panel forming at least a roof rail outer (28), a center pillar outer (30) and a side sill outer (32) and being manufactured by press molding; and an inner closed section structure (10) disposed along areas of the roof rail outer (28), the center pillar outer (30) and the side sill outer (32) of the outer panel structure (8) and attached to the outer panel structure (8), said inner closed section structure (10) having a sectional configuration which changes in accordance with changes in the inner side configuration of the outer panel structure (8) and being manufactured by a tube hydraulic forming method, said inner closed section structure (10) functioning as a part of the inner section of the body structure (1). A body structure of a motor vehicle according to claim 1, wherein said inner closed section structure (10) is supported by inner bands (12) which are respectively connected with flanges (12a) of the roof rail outer (28) and the center pillar outer (30). A body structure of a motor vehicle according to claim 1, wherein said inner closed section structure (10) is supported by inner bands (12) which are respectively connected with flanges (12a) of the center pillar outer (30) an the side sill outer (32). A body structure of a motor vehicle according to claim 1, wherein said outer panel structure (8) is an integral panel forming at least a center pillar outer (30) and a roof outer (28), and said inner closed section structure (10) is integrally disposed along areas of the center pillar outer (30) and the roof outer (28) of the outer panel structure (8). A body structure of a motor vehicle according to claim 1, wherein said outer panel structure (8) is an integral panel forming at least a center pillar outer (30) and a floor outer (32), and said inner closed section structure (10) is integrally disposed along areas of the center pillar outer (30) and the floor outer (32) of the outer panel structure. A body structure of a motor vehicle according to any of claims 1-5, wherein said inner closed section structure (10) has a closed section integrally disposed along areas of a center pillar section, a roof section (52) and a floor section (54) of the outer panel structure (8). A body structure of a motor vehicle according to any of claims 1-6, wherein said inner closed section structure (10) has a closed section integrally disposed along areas of a center pillar section, a roof section (52), a floor section (54) and a roof rail section of the outer panel structure (8). A body structure of a motor vehicle according to any of claims 1-7, wherein said inner closed section structure (10) has a closed section integrally disposed along areas of a center pillar section, a roof section (52), a floor section (54) and a side sill of the outer panel structure (8). A body structure of a motor vehicle according to claim 2, wherein said integral panel of the outer panel structure (8) has a flange (28a) to which seal means (36) is attached.

Inventors: HARASAKI HAYATSUGU, OKANA FUMIO, HARASAKI, HAYATSUGU, OKANA, FUMIO
Applicants: MAZDA MOTOR, MAZDA MOTOR CORPORATION
Application year: 2000
Main classification: B62D25
IPC codes: B62D25