Abstract:
A seat pad with a fastener is manufactured by forming a groove in a mold, arranging a longitudinal end of the groove, disposing the fastener on the mold to have the surface of the fastener facing the groove, curving a longitudinal end of the fastener to protrude in the mold, and injecting a forming synthetic resin into the mold.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a vehicle seat, and more particularly, to a method of manufacturing a foamed seat pad having a flat fastener integrated therewith and a seat with the pad resulting therefrom. 
     Conventionally, a seat such as a vehicle seat includes a pad made of urethane foam or the like and a skin disposed thereon. In order to attach the skin to the pad, a wire is inserted in and formed with the pad, and is fixed to the skin by a mounting hardware such as a C-shaped clip and a hog ring. 
     In recent years, a novel fastening structure is proposed, for example, in U.S. Pat. No. 5,972,465 issued Oct. 26, 1999 to Ohno et al. and U.S. Pat. No. 6,045,731 issued Apr. 4, 2000 to Matsuoka. The structure comprises a flat fastener including an engagement portion formed on the surface of a belt-like base and having a plurality of engagement protrusions and an embedded portion formed on the back of the base and having a plurality of embedded elements. The fastener is embedded in the surface of a pad by means of molded-in forming. And the engagement portion is engaged with the back of a skin for positioning thereof. 
     However, the structure wherein a wire is inserted in and formed with the pad, and is fixed to the skin by a mounting hardware needs a number of tools which complicate work, resulting in deteriorated workability. Moreover, metal parts are mixedly arranged in the pad, resulting in not only uneasy disassembly of the pad, but poor recyclability and cost efficiency thereof. 
     The structure using a flat fastener has the drawback that the fastener can separate from the skin, making positioning of the skin difficult. 
     It is, therefore, an object of the present invention to provide a method of manufacturing a foamed seat pad having a flat fastener integrated therewith, which ensures not only excellent recyclability and cost efficiency thereof, but excellent positioning of a skin. 
     SUMMARY OF THE INVENTION 
     An aspect of the present invention lies in providing a method of manufacturing a seat pad with a fastener, comprising the steps of: 
     forming a groove in a mold; 
     arranging a longitudinal end of said groove; 
     disposing the fastener on said mold to have a surface of the fastener facing said groove; 
     curving a longitudinal end of the fastener to protrude in said mold; and 
     injecting a forming synthetic resin into said mold, 
     whereby the seat pad is obtained, having said longitudinal end of the fastener embedded in said seat pad. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a fragmentary longitudinal section showing a seat including a skin and a pad embodying the present invention; 
     FIG. 2 is a cross section showing the pad having a flat fastener integrated therewith; 
     FIG. 3 is an enlarged fragmentary section showing the fastener disposed in an U-shaped groove of a female mold; and 
     FIG. 4 is a view similar to FIG. 1, showing a foam mold in which an end of the fastener is disposed on a wall of the female mold. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings, a description will be made with regard to embodiments of a method of manufacturing a foamed seat pad having a flat fastener integrated therewith and a seat with the pad resulting therefrom. 
     Referring to FIGS. 1-2, a vehicle seat  11  includes a pad  13  mounted to a seat frame, not shown, and a skin  15  disposed thereon. The pad  13  is obtained by means of foaming, having a belt-like flat fastener  21  integrated therewith. Specifically, the pad  13  is made such that the fastener  21  is disposed in a foam mold  31 , and a foaming synthetic resin is injected therein to obtain the pad  13  having the fastener  21  integrated therewith. For positioning of the skin  15 , the back of the skin  15  is engaged with the surface of the fastener  21 . 
     The skin  15  includes a skin portion  15   a  arranged on the surface and a backing portion  15   b  arranged on the back. The skin  15  may include a single layer or three layers. The fastener  21  is formed to correspond to a pulled portion, a pattern juncture or the like of the skin  15 . The skin  15  may include a counter-engagement portion on the back to face the fastener  21  for engagement therewith. 
     As seen in FIG. 2, the fastener  21  includes a belt-like base  22  made of a synthetic resin, an engagement portion  23  formed on the surface of the base  22  and having a plurality of engagement protrusions with a head of wedge-like or mushroom-like section, and an embedded portion  24  formed on the back of the base  22  and having a plurality of embedded elements with a head of mushroom-like or circular section. The structures of the engagement portion  23  and the embedded portion  24  are not limited to those as shown in FIG.  2 . By way of example, the embedded elements of the embedded portion may be of different lengths. 
     The fastener  21  is arranged such that the whole of the embedded portion  24  is embedded in the pad  13 , and the principal part of the engagement portion  23  arranged on the surface of a main portion or longitudinally center portion  21   a  of the fastener  21  is exposed on the surface of the pad  13 . 
     Both longitudinal ends  21   b  of the fastener  21  are curved or bent inward of the pad  13  to be embedded therein. In the embodiment, inward curvature or bend is carried out with respect to the both ends  21   b . Alternatively, it may be carried out with respect to only one end  21   b.    
     Referring to FIGS. 3-4, a description will be made with regard to the method of manufacturing the foamed seat pad  13  having the flat fastener  21  integrated therewith. 
     As shown in FIG. 3, a groove  35  of U-shaped section is formed in a female mold  32  of the foam mold  31 . The groove  35  is arranged in a convex portion  33  that protrudes upward from a molding surface  32   a  of the female mold  32 . The groove  35  may be formed in a female mold with no convex portion  33 . 
     In the embodiment as shown in FIG. 3, the convex portion  33  is integrally formed with the female mold  32  to obtain the groove  35  therein. Alternatively, as shown in FIG. 4, a detachable guide  36  may separately be arranged with the female mold  32  to obtain the groove  35  therein. 
     In the embodiment as shown in FIG. 4, a wall  33   a  is formed at each longitudinal end of the groove  35 . Alternatively, the wall  33   a  may be eliminated or replaced with a crosspiece. The crosspiece can be arranged vertically adjustably. 
     The fastener  21  is disposed such that principal part of the engagement portion  23  arranged on the surface of the main portion  21   a  faces the groove  35  of the female mold  32 . Each end  21   b  of the fastener  21  is in close contact with the groove  35  to prevent the entry of the foaming synthetic resin. 
     As shown in FIG. 4, each end  21   b  of the fastener  21  is disposed on the wall  33   a  of the groove  35  of the convex portion  33  for upward curvature, obtaining the end  21   b  protruding in the foam mold  31 . In the case where a crosspiece is disposed at each end of the groove  35 , each end  21   b  of the fastener  21  is disposed on the crosspiece. 
     In the case where the guide  36  is arranged with the female mold  32  to obtain the groove  35  therein, each end  21   b  of the fastener  21  is disposed on the upper end of the wall  33   a  of the guide  36 . 
     The foaming synthetic resin is injected into the female mold  32  of the foam mold  31  to obtain the pad  13  having the fastener  21  integrated therewith. Through this foaming of the pad  13 , the embedded portion  24  formed on the back of the base  22  of the fastener  21  is embedded in the pad  13 . Moreover, each end  21   b  of the fastener  21 , which is curved or bent inward of the pad  13 , is embedded therein. 
     In the embodiment, in order to curve or bend both ends  21   b  of the fastener  21 , they are disposed on the walls  33   a  of both ends of the convex portion  33 . Alternatively, a fastener with previously curved or bent ends  21   b  may be applied without arranging any walls  33   a.    
     Having described the present invention with regard to the preferred embodiments, it is noted that the present invention is not limited thereto, and various changes and modifications can be made without departing the scope of the present invention. By way of example, in the embodiment, the present invention is applied to a seat cushion. Alternatively, the present invention is applicable to a seat back. 
     The entire contents of Japanese Patent Application P11-123666 are incorporated herein by reference.