SEAT BODY

Abstract: A seat body in which an outer cover (3) is bonded along the outer surface of a urethane mold or a molded slab (2), wherein not a one-piece uncut outer cover but cut and div­ ided outer covers or a partially-cut outer cover is used, the portions to be bonded or required portions of divided outer covers being folded, and buried in and fixed to the inside of the grooves in the mold (2) to thereby finish the outer covers in a three-dimensional shape.

Description: Technical Field This invention relates to a seat, and more particularly to a bucket seat for use in an automotive vehicle of the kind specified in the preamble of claim 1. That is, the present invention provides a seat which can be manufactured compactly and easily without requiring the skill and some steps which have been required hitherto for the manufacture of such a seat. Background Art Some prior art seats will be described with reference to Figs. 14 to 16. A first prior art example shown in Figs. 14a to 14f represents a seating part of a bucket seat for use in an automotive vehicle. Therefore, this seat has a seat base part A, flap parts B and side parts C. As shown in Figs. 14b and 14c, the internal structure of the seat includes a trim cover 1 mounted on a surface of a so-called molded polyurethane foam 2 obtained by foaming and molding a polyurethane resin in a mold (which foam may be replaced by a so-called shaped slab cut from a block of a foamed polyurethane resin). As shown in Fig. 14d, the trim cover 1 is composed of a cover member 3, a filler pad 4 and a backing cloth 5. As shown in Fig. 14a, this seat has a complex three-dimensional shape, and the entire trim cover 1 is provided by preparing an element cut into a developed shape of the seat base part A, elements cut into developed shapes of the left and right flap parts B and elements cut into developed shapes of the left and right side parts C, and sewing them by a sewing machine or welding them by high-frequency welding. The trim cover 1 formed into such a three-dimensional shape is mounted on the molded polyurethane foam 2. Since the trim cover 1 has a concave configuration, it is necessary to pull downward, for example, a portion XIVe in Fig. 14b and a portion XIVf in Fig. 14c. For this purpose, suspension slits 8 are formed in the corresponding portions of the molded polyurethane foam 2, and these portions of the trim cover 1 are pulled by suspension strips 6 and retained by retaining wires 7. As shown in Figs. 14e and 14f which illustrate the details of the suspension and retaining mechanism, the suspension strip 6 is fastened (sewing by a sewing machine or welding by high-frequency welding) to the trim cover 1 at a portion S, and the suspension strip 6 is combined together at another portion 5 adjacent to the lower end thereof to form a loop into which the retaining wire 7 is inserted. The individual steps of manufacturing such a seat having the illustrated structure require many skilled workers and require also many man-hours as well as heavy labor. Especially, because of the requirement for preparation of various elements including the suspension strips 6, retaining wires 7 and suspension slits 8, the seat is defective in that the cost is high, and the quality is also unstable. Another prior art example shown in Figs. 15a and 15b is a modification of the prior art example described above. The flap part B of the trim cover 1 extends to the side part C and is pulled inward along a line 9. This state is best shown in Fig. 15b. The side part C is also pulled inward along the line 9 and is retained by a retaining wire 7 disposed in the trim cover 1. This structure is advantageous from the aspect of design when different materials, colors, etc. are requested for the flap parts B and side parts C of the trim cover 1. However, the suspension and retaining mecanism is troublesome, and the seat is more disadvantageous than the first-mentioned prior art example from the aspect of manufacture. A third prior art example shown in Figs. 16a to 16e is a seat having a more complex three-dimensional shape. That is, a seat base part of this example includes four ridges A₁, A₂, A₃ and A₄, and square grooves 10 as shown in Figs. 16a and 16b are formed therebetween. In correspondance with the above ridges, flap parts B have also four ridges B₁, B₂, B₃ and B₄ as shown in Figs. 16a and 16c. In this example too, as in the case of the aforementioned prior art examples, suspension slits 8 formed in a molded polyurethane foam between the seat base part and the flap parts are utilized to retain the trim cover by retaining wires through suspension strips 6. Similar retaining arrangement is also provided between the ridges of the flap parts as shown in Figs. 16c. Further, in the case of the square grooves 10 formed in the seat base parts, it is necessary to fix the suspension strips 6 shaped to conform to the shape of the square grooves so as to retain the seat base part as shown in Figs. 16b and 16e. That is, the flap part B is split into sub-parts B₁, B₂, B₃ and B₄ for which respectively different three-dimensional shapes are required. Depending on the specification, the seat base part A may be split into separate sub-parts A₁, A₂, A₃ and A₄ and, in such a case, a defect similar to but greater than that described already results. The presence of many suspension slits 8 in the molded polyurethane foam 2 and the complexity of the shape of the molded polyurethane foam 2 lead to the possibility of production of many rejects, and the presence of mary suspension slits 8 degrades the cushion effect. In a product proposed for solving the above problem, a highly stretchable one-piece cover member is stretched ant bonded to a molded polyurethane foam 2. However, such a highly stretchable cover member is expensive, and the equipment cost that must be invested for carrying out shaping and bonding of time entire cover member is enormous. Also, the possibility of occurrence of folds ant wrinkles at the bonded area is high. From GB-A-1 141 694 there is known a seat construction comprising a body made of a molded elastic member having an uneven upper surface, and a covering connected to the body, wherein the body has grooves formed therein and the covering has portions inserted in the grooves and secured therein. The covering is composed of a plurality of individual cover members, of different material, which are previously cut into shapes so that the whole covering results from connection of the individual members. The marginal edges of the said cover members are sewn or bonded together and the entirety of the cover members including the edges, is bonded to the body of elastic material. This requires considerable labor and costs for shaping the individual cover members and bonding them to each other and to the elastic member. Same applies to the seat cushion of US-A-3 337 884, in which a covering is provided of individual portions previously cut and then connected together at ends thereof, and in which a flexible and resilient upper cover member of an elastic fabric is used, which additionally requires to be sewn at a central concave portion to an underlying elastic pad and to be stretched before being connected at the ends with the adjacent cover member. GB-A-786 289 teaches a seat or the like of the type in which a covering is connected to a body of elastic material, wherein the body has a plurality of slits in the upper surface which terminate with enlarged channels at the bottom. The covering is prepared with seams, piping or creases, at positions corresponding with the slits, and these seams or the like are pressed through the slits and into the bottom channels where they become housed and eventually bonded to the elastic material. This requires particular skill and precision for preparing the seams to correspond with the slits in the elastic body and only very simple seat configurations can be provided at reasonable costs. Another seat construction including covering members bonded to an elastic seat body is known from GB-A-1 061 806. In this seat, side portions of the covering are connected to a seating portion at joints by means of sewing with a sewing machine or welding with a high-frequency welder. The so obtained covering is turned over and bonded to a foamed polyurethane block forming the elastic seat body. This known construction requires shaping and preliminary joining of individual covering portions and then a bonding step, which result in relatively high manufacturing costs. Sale applies to the seat cushion of US-A-3 566 423, where separate portions of the covering need to be preliminarily sewn together before being bonded to a seat body made of polyurethane material. Disclosure of the invention It is an object of the present invention to provide a seat in which suspension strips, retaining wires, suspension slits, etc. are eliminated and the structure and manufacturing are simplified so that there is not required any especial skill and time and costs for production are reduced. The above object is solved by a seat having the features of claim 1. That is, a one-piece cover member is used which is cut into shaped portions conforming to a three-dimensional shape and the ends of which are buried into grooves of a molded elastic member, and the cover member is bonded to the molded elastic member at the necessary portions only to provide a seat. According by, bonding at necessary portions only reduces man-hours, saves the bonding agent and ensures satisfactory feeling of cushion. Production of the seat does not require any especial skill, and use of a fabric or the like as the cover member provides satisfactory air permeability. There is a great degree of freedom for the selection of the material of the cover member. The cover member is not an especially highly stretchable cover member for a pre-shaped seat, and a cover member less expensive can be used. Brief Description of the Drawings Figs. 1 to 13 relate to the present invention in which Fig. 1 is a vertical sectional view taken along a longitudinal direction of a seating part of a bucket seat (corresponding to the XIVb-XIVb section in Fig. 14a), Fig. 2 is a vertical sectional view taken along a transverse direction of the seating part of this bucket seat (corresponding to Fig. 14c), Fig. 3 is a vertical sectional view of another seating part (corresponding to the XVIb-XVIb section in Fig. 16a), Fig. 4 is a sectional view of a flap part of Fig. 3 (corresponding to Fig. 16c), Fig. 5a is an enlarged view of a portion Va in Fig. 2, Fig. 5b is an enlarged view of a modification of the portion Va, Fig. 5c is an enlarged sectional view of a portion Vc in Fig. 3, Fig. 5d is a similar sectional view of an example in which cover members are superposed, Fig. 6a is a sectional view of an example in which a filler pad is interposed between a cover member and a molded polyurethane foam, Fig. 6b is a sectional view of an example whose purpose is the same as that the Fig. 6a and in which a square groove is formed, Fig. 7 is a schematic vertical sectional view of an example of a front back and a seating part to which the present invention is applied, Fig. 8 is a sectional view of an example in which cutouts are formed on a single cover member at one side, and the cover member is bonded at the cutout portions, Fig. 9 is a sectional view of an example in which upper and lower cutouts are formed, Fig. 10 is a vertical sectional view taken along a transverse direction of an embodiment in which a flap part of a cover member is extended to a side of a seat and tuched together with a side-part cover member into a molded polyurethane foam (corresponding to the XVb-XVb section in Fig. 15b), Fig. 11 is a side elevation view of an embodiment in which a line is formed on a side of a seat as in the case of the embodiment shownn Fig. 10, but in which the same single cover member is used, Fig. 12 is a sectional view taken along the line XII-XII in Fig. 11, and Fig. 13 is a sectional view taken along the line XIII-XIII in Fig. 11. Figs. 14 to 16 relate to prior art examples, in which Fig. 14a is a perspective view of a seat, Fig. 14b is a sectional view taken along the line XIVb-XIVb in Fig. 14a, Fig. 14c is a sectional view taken along the line XIVc-XIVc in Fig. 14a, Fig. 14d is an enlarged view of a portion XIVd in Fig. 14b, Fig. 14e is an enlarged view fo a portion XIVb in Fig. 14, Fig. 14f is an enlarged view of a portion XIVf in Fig. 14c, Fig. 15a is a perspective view of a seat which is generally similar to that of Fig. 14a, but in which a joint line is formed on a side of the seat, Fig. 15b is a sectional view taken along the line XVb-XVb in Fig. 15a, Fig. 16a is an external perspective view of a third seat, Fig. 16b is a sectional view taken along the line XVIb-XVIb in Fig. 16a, Fig. 16c is a sectional view taken along the line XVIc-XVIc in Fig. 16a, Fig. 16d is a sectional view taken along the line XVId-XVId in Fig. 16a, and Fig. 16e is an enlarged sectional view of a portion XVIe in Fig. 16b. Best Mode for Carrying out the Invention For clarifying the present invention in further detail, embodiments illustrated in Figs. 1 to 13 will be described. A first embodiment of the present invention shown in Figs. 1 and 2 correspond in shape to the prior art example shown in Figs. 14a to 14f. That is, the external shape is the same as that shown in Fig. 14a, and Fig. 1 corresponds to Fig. 14b, while Fig. 2 corresponds to Fig. 14a. It will be apparent from Fig. 1 that, in this embodiment, a cover member 3 is joined to another cover member 3′ at an area of a seat base part corresponding to the lowest area of the seat base part where the seat base part is pulled downward by the suspension strip 6 in the prior art example shown in Fig. 14b, and the junction 11 therebetween is bonded to a groove 12 previously formed in a molded polyurethane foam 2. At concave portions between the seat base part and flap parts too, the cover member 3 providing the seat base part is similarly joined to cover members 3″ providing the flap parts, and the junctions 11′ therebetween are similarly bonded to grooves of the molded polyurethane foam 2, as shown in Fig. 2. The portion Va is shown in an enlarged scale in Fig. 5a. As indicated by dotted lines in Fig. 5a, the flap part may be joined to the seat base part at the same height. Fig. 5b illustrates the case where the cover member 3 is tucked and bonded at a zone where it is not cut. In this case, the depth D of the tuck may be locally changed so that the cover member conforms to the outer configuration of the molded polyurethane foam. Anyway, by so arranging, the seat has the same finished three-dimensional shape as that of the prior art example shown in Fig. 14 without bonding the other portions. That is, the cover member is free from the polyurethane foam 2 at the remaining area and the labor required for suspension and retaining work becomes utterly unnecessary. In this embodiment, a trim cover as shown in Fig. 14d was not used, and the cover member 3 only was used. An Example of this cover member 3 is moquette. The cover members 3, 3′ and 3″ may be cut from the same material or from different materials or from a material having different colors. Fig. 5d illustrates the case where the cover members 3 and 3′ are laid and bonded together in a state folded along the seat surface. Figs 3 and 4 show a second embodiment of the present invention which is equivalent in shape to the prior art example illustrated in Figs. 16a to 16e. That is, Fig. 3 is a vertical sectional view taken along a longitudinal direction of a seat base part and corresponds to Fig. 16b, while Fig. 4 is a vertical sectional view taken along a longitudinal direction of a flap part and corresponds to Fig. 16c. It will be apparent from Fig. 3 that cover members 3 and 3′ are bonded to a molded polyurethane foam 2 in square grooves 10. The cover members 3 and 3′ are joined in a square groove portion indicated by Vc. Fig. 5c is an enlarged view of this portion Vc, and the square groove formed in the molded polyurethane foam is further depressed downward at the position of the junction between the cover members. At this portion Vc too, the cover members 3 and 3′are securely bonded to the molded polyurethane foam. However, the entirety of the seat base part may be formed of the cover member 3 only when such is required. Fig. 4 illustrates that the cover member 3 forming portions B₁, B₂, B₃ and B₄ of the flap part B is cut into portions conforming to plane-developed patterns of the three-dimensional shapes of the respective portions of the seat, and such cut portions are buried in grooves of the molded polyurethane foam 2 and bonded at their junctions 11″. Fig. 6a illustrates a structure in which a filler pad 4 is interposed between a molded polyurethane foam 2 and a cover member 3. This structure can exhibit the soft feeling of the filler pad. The filler pad 4 and the cover member 3, and the filler pad 4 and the molded polyurethane foam 2 are bonded at necessary portions. Fig. 6b, the purpose of which is similar to that of Fig. 6a, illustrates another method of forming the square groove 10 shown in Fig. 3. The cover member 3 is tucked at this groove and buried and bonded therein. Cutouts 3a are formed on a single cover member 3 for instance as shown in Fig. 8, and the cut portions of the cover member 3 are buried into the grooves in a molded polyurethane foam 2 at portions outer than the dotted lines, specifically at the end edges, and are then bonded to the molded polyurethane foam 2. By suitably selecting the relation L > I > l₁, the height of the three-dimensional shapes can be changed. Although not illustrated, an upper portion 3b of each of the cutouts 3a may be eliminated to leave an uncut portion similar to the lower portion, and the central cutouts 3a may only be formed on a same side of the cover member. In contrast, Fig. 9 illustrates that upper cutouts 3b and lower cutouts 3c are formed on opposite sides of the cover member. As shown in each of Figs. 8 and 9, the cover member 3 is not separated but is in a continuous one-piece form. At the mutually connected zones the portions between the dotted lines are tucked into the groove of the foam 2. Therefore, the cover member 3 can be easily handled to reduce man-hours, to improve the yield rate of the material, and to eliminate fluctuations of the resultant shape. The local cutting of the cover member 3 is not limited to the shapes shown in Figs. 8 and 9 and may be suitably modified to meet any requirement for the three-dimensional shape. In an embodiment shown in Fig. 10, the aforementioned prior art seat shown in Figs. 15a and 15b, that is, the seat having the side joint line 9 between the flap part and the side part is formed according to the present invention. According to the present invention, a cover member 3 providing the flap part B is extended to the, side face of the seat as shown in Fig. 10, and, at this side face, the end edge of the cover member 3 is buried, together with the end edge of a cover member 3‴ providing the side part C, into an insertion groove formed in a molded polyurethane foam 2 to be bonded the walls of the grooves. According to such an arrangement, the troublesome mechanism requried for achieving suspension inside the molded polyurethane foam shown in Fig. 15b becomes utterly unnecessary. Figs. 11 to 13 show a modification in which a filler pad 4 is used in the seat having the side joint line 9 described above. In this case, a one-piece cover member 3 as shown in Fig. 12 is used and tucked between and bonded to the molded polyurethane foam 2 and the filler pad 4 thereby forming the joint line. It is needless to mention that the cover member 3 may be previously cut at the joint line 9. The front end overhang portion B′ of the flap part B is provided by wrapping the filler pad 4 in the cover member 3, then bending the combination downward as shown by the arrow, and fixing the combination to the side part C. Fig. 13 is an enlarged sectional view of the front end portion B′ after being fixed. This bent end portion may be further extended to a lower portion of the seating part or to a rear portion of the front back as shown in Fig. 7. A fabric which is unstretchable or scarcely stretchable is used as the cover member 3. The side part C may be separately prepared and combined with the other part through welts (not shown) or without the use of wilts. Or, the side part C may be separated from the flap part by a joint line 9 as shown in Fig. 11. Or, a suitable cutout or cutouts as shown in Fig. 8, 9 or 10 may be formed in the flap part B, and such a flap part B may be combined integrally with the side part C. The tucked portion of the cover member is in no way limited to those illustrated in the figures described above and, the cover member may be tucked at any other required portion. The bonding agent may be such that it can be sprayed or applied by hand, or may be in the form of powders of a heat-fusible bonding material, or in the form of a cloth, a film, a tape, a velvet cloth or the like of such a bonding material. Or, a heat-fusible bonding material may be previously coated on the necessary portions of the cover member. The backing cloth 5, suspension strips 6, retaining wires 7 and suspension slits 8 are eliminated, and bonding is applied to necessary portions only. Therefore, the bonding agent can be saved, the material costs can be saved and the manufacturing cost can be reduced. Use of a fabric or the like as the material of the cover member improves the air permeability. An ordinary material (a fabric or a vinyl leather) commonly used to provide a trim cover can also be used as the material of the cover member. Therefore, the degree of freedom of selection of the cover material is large, and the cover member is less expensive than an especially highly stretchable cover member for a pre-shaped seat. In the case of the overhang type shown in Fig. 11, the overhang structure can be provided by bending and bonding a shape shown by the dotted lines, and wrinkles may be produced on this overhang portion. The reject rate of the molded polyurethane foam is decreased. Industrial Applicability The aforementioned embodiments have referred to an application of the present invention to a bucket seat for use in an automotive vehicle. However, it is apparent that the present invention is in no way limited to the bucket seat and is also applicable to various other seats for use in an automotive vehicle and to chairs and similar seating articles of furniture.

Claims: 1. A seat comprising a body made of a molded elastic member (2) having an uneven upper surface, and a cover member (3, 3′, 3″, 3‴) connected to the body, wherein the body (2) has grooves (12) formed therein and the cover member (3, 3′, 3″, 3‴) has portions inserted in the grooves (12) and secured therein, characterized in that an unstretchable or substantially unstretchable, one-piece cover member (3, 3′, 3″, 3‴) has shaped cutout portions formed around the edges thereof to conform said cover member (3, 3′, 3″, 3‴) to an overall three-dimensional shape of the seat, and in that only the end edges of said portions are buried in said grooves (12) and bonded to the grooves (12), while said cover member (3, 3′, 3″, 3‴) is free from said elastic member (2) at the remaining area. 2. A seat as claimed in claim 1, characterized in that tucked portions of said cover member (3, 3′, 3″, 3‴) are further buried and bonded in said grooves (12). 3. A seat as claimed in claim 1 or 2, characterized in that the end edges of said cover member (3, 3′ 3″, 3‴) or the tucked portions of said cover member (3, 3′ 3″, 3‴) are buried and bonded in square grooves (10) of said elastic member (2). 4. A seat as claimed in claim 1, characterized in that the end edges of said cover member (3, 3′, 3″, 3‴) are buried and bonded in a state laid and folded along the seat surface. 5. A seat as claimed in claim 1, characterized in that the elastic member (2) is a molded polyurethane foam or a molded slab of foamed polyurethane. 6. A seat as claimed in claim 5, characterized in that a filler pad (4) is interposed between said cover member (3, 3′, 3″, 3‴) and said molded polyurethane foam or molded slab. 7. A seat as claimed in claim 1, characterized in that a cover member (3′) providing a flap part of the seat is buried and bonded in a groove (12) together with a cover member (3‴) providing a side part of the seat. 8. A seat as claimed in claim 7, characterized in that the line (9) of said groove extends to a front overhang, and the flap part of said overhang is bent downward. 9. A seat as claimed in claim 8, characterized in that the front end of said overhang extends to a rear side of the seat. 10. A seat as claimed in claim 1, characterized in that the cover member (3) is cut in a form having cut-out portions (3a, 3b) on a same side. 11. A seat as claimed in claim 1, characterized in that the cover member (3) is cut in a form having cut-out portions (3b, 3c) on opposite sides.

Inventors: URAI, MUNEHARU
Applicants: TACHI-S CO. LTD.
Application year: 1986
Main classification: B68G7
IPC codes: A47C7, B60N2, B68G7, A47C31, B29D99