Abstract:
A manufacturing method of a trim cover surface material, includes: providing a jig including a first frame configured to hold an outer periphery of an outer material and a second frame configured to hold an outer periphery of a wadding material by overlapping the wadding material on the outer material which is held by the first frame; holding the outer periphery of the outer material with the first frame of the jig; forming through holes at the outer material which is held by the jig; holding the outer periphery of the wadding material with the second frame of the jig while the outer material is held by the first frame of the jig; and forming stitches at the outer material and the wadding material which are overlapped and held by the jig.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
       [0001]    This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2016-088331, filed on Apr. 26, 2016, the entire contents of which are incorporated herein by reference. 
       BACKGROUND 
     1. Field of the Invention 
       [0002]    The present invention relates to a manufacturing method, a manufacturing apparatus and a manufacturing jig of a trim cover surface material. 
       2. Description of the Related Art 
       [0003]    A vehicle seat typically includes a cushioning pad and a trim cover that covers the cushioning pad, and the trim cover is made by sewing a plurality of surface materials. Leather (natural leather, synthetic leather) is used as an example of the surface material, and, from a view of improving breathability and design, a large number of through holes may be formed at the leather by a predetermined pattern. Furthermore, from a view of improving design of the seat, stitches may be formed at the surface material, and the stitches avoid the through holes of the surface material and are formed at the gap part between through hole patterns (for example, refers to JP-A-2013-162957). 
         [0004]    The trim cover surface material described in JP-A-2013-162957 is formed by laminating a wadding material made of foaming resin such as slab urethane on an outer material of leather which is formed with a plurality of through holes, and the leather and the wadding material are bonded. To secure the breathability of the leather, the leather is bonded with the wadding material at the outer periphery except where the through holes are formed. The stitches are formed at the gap part between the through hole patterns of the surface material. 
         [0005]    The stitches of the surface material are typically formed by using a sewing machine driven according to a program. In automatic sewing using this kind of sewing machine, the sewed object such as the surface material is installed on the sewing machine while, for example, the outer periphery is held by a frame-like jig, and slack is removed (for example, refers to JP-B-H07-38907). 
         [0006]    The surface material described in JP-A-2013-162957 is formed by laminating the wadding material on the leather which is formed with through holes beforehand, but, for example, when the leather which are formed with the through holes beforehand are procured from outside, a relatively long time elapses from when the leather is formed with the through holes until the stitches are formed at the surface material. 
         [0007]    If the elapsed time after the leather is formed with the through holes becomes long, the leather deforms under the influence of temperature and humidity, and due to the deformation of the leather, the through hole patterns may be deviated. When the through hole patterns are deviated, misalignment of the stitches which the surface material is formed with by automatic sewing and the through hole patterns may occur, and design may be spoiled. 
         [0008]    For the surface material described in JP-A-2013-162957, the leather is bonded with the wadding material at the outer periphery except where the through holes are formed, but when the stitches are formed by automatic sewing, the outer periphery of the surface material is held by a jig. Therefore, the leather and the wadding material are bonded, and then the surface material whose leather and wadding material are bonded is set on the jig, but an error in the positioning of the surface material to the jig may occur, and when the leather is deformed, the positioning of the surface material becomes further harder. When the error occurs in the positioning of the surface material, misalignment of the stitches and the through holes may occur and design may be spoiled. 
       SUMMARY 
       [0009]    The present invention is made in view of the above circumstances, and the object of the present invention is to provide a manufacturing method and a manufacturing apparatus of a trim cover surface material and a manufacturing jig which can inhibit the misalignment of stitches and through hole patterns. 
         [0010]    According to an aspect of the present invention, there is provided a manufacturing method of a trim cover surface material, the trim cover surface material including: an outer material which is formed with a plurality of through holes by a predetermined pattern; and a wadding material laminated on the outer material, the trim cover surface material being formed with stitches that sew together the outer material and the wadding material at gap portions between through hole patterns, the manufacturing method including: providing a jig including: a first frame configured to hold an outer periphery of the outer material; and a second frame configured to hold an outer periphery of the wadding material by overlapping the wadding material on the outer material which is held by the first frame; holding the outer periphery of the outer material with the first frame of the jig; forming the through holes at the outer material which is held by the jig; holding the outer periphery of the wadding material with the second frame of the jig while the outer material is held by the first frame of the jig; and forming the stitches at the outer material and the wadding material which are overlapped and held by the jig. 
         [0011]    According to another aspect of the present invention, there is provided a manufacturing apparatus of a trim cover surface material, the trim cover surface material including: an outer material which is formed with a plurality of through holes by a predetermined pattern; and a wadding material laminated on the outer material, the trim cover surface material being formed with stitches that sew together the outer material and the wadding material at gap portions between through hole patterns, the manufacturing apparatus including: a drilling machine and a sewing machine which are installed sequentially on a production line; and a jig which holds the outer material and the wadding material, wherein: the jig includes: a first frame configured to hold an outer periphery of the outer material; and a second frame configured to hold an outer periphery of the wadding material by overlapping the wadding material on the outer material which is held by the first frame; the drilling machine includes an installing part on which the jig is installed; the drilling machine forms the through holes at the outer material which is held by the jig which is installed on the installing part; the sewing machine includes an installing part on which the jig is installed; and the sewing machine forms the stitches at the outer material and the wadding material which are held by the jig which is installed on the installing part. 
         [0012]    According to still another aspect of the present invention, there is provided a manufacturing jig of a trim cover surface material, the trim cover surface material including: an outer material which is formed with a plurality of through holes by a predetermined pattern; and a wadding material laminated on the outer material, the trim cover surface material being formed with stitches that sew together the outer material and the wadding material at gap portions between through hole patterns, the manufacturing jig including: a first frame configured to hold an outer periphery of the outer material; and a second frame configured to hold an outer periphery of the wadding material by overlapping the wadding material on the outer material which is held by the first frame. 
         [0013]    According to the present invention, the misalignment of stitches and through hole patterns can be inhibited. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawing which is given by way of illustration only, and thus is not limitative of the present invention and wherein: 
           [0015]      FIG. 1  is a perspective view of a vehicle seat to describe an embodiment of the present invention; 
           [0016]      FIG. 2  is a sectional view of a surface material of  FIG. 1 ; 
           [0017]      FIG. 3  is a schematic diagram of a manufacturing apparatus of the surface material of  FIG. 1 ; 
           [0018]      FIG. 4  is a perspective view of a manufacturing jig of the surface material of  FIG. 1 ; 
           [0019]      FIG. 5  is a perspective view which shows that the manufacturing jig of  FIG. 4  is opened; 
           [0020]      FIG. 6A  is a schematic diagram to describe a manufacturing process of the surface material of  FIG. 1 ; 
           [0021]      FIG. 6B  is a schematic diagram to describe a manufacturing process of the surface material of  FIG. 1 ; 
           [0022]      FIG. 6C  is a schematic diagram to describe a manufacturing process of the surface material of  FIG. 1 ; 
           [0023]      FIG. 6D  is a schematic diagram to describe a manufacturing process of the surface material of  FIG. 1 ; and 
           [0024]      FIG. 6E  is a schematic diagram to describe a manufacturing process of the surface material of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0025]      FIG. 1  shows an example of the vehicle seat to describe an embodiment of the present invention. 
         [0026]    A vehicle seat  1  shown in  FIG. 1  includes a seat cushion  2  which forms a bearing surface portion, a seat pack  3  which forms a back rest portion, and a head rest  4  which supports the head of a passenger who is seated on the seat. Each of the seat cushion  2 , the seat pack  3  and the head rest  4  has a cushioning pad made of foam material such as urethane foam, and a frame which supports the cushioning pad. 
         [0027]    The cushioning pad of the seat cushion  2  and the cushioning pad of the seat pack  3  are covered integrally with a trim cover  5 , and the cushioning pad of the head rest  4  is also covered with the trim cover  5  or another trim cover. 
         [0028]    The cushioning pad of the seat cushion  2  and the cushioning pad of the seat pack  3  may be covered by individual trim covers, respectively, and when the head rest  4  is a fixed head rest and is formed integrally with the seat pack  3 , the cushioning pad of the head rest  4  may be covered integrallly with the cushioning pad of the seat pack  3  by one trim cover, or may be covered integrallly with the cushioning pad of the seat cushion  2  and the cushioning pad of the seat pack  3  by one trim cover. 
         [0029]    The trim cover  5  is formed by sewing and joining a plurality of surface materials, and among the plurality of surface materials that form the trim cover  5 , for example, a surface material  6  which covers the central portion in the widthwise direction of the front surface of the seat pack  3 , and a surface material  7  which covers the central portion in the widthwise direction of the bearing surface of the seat cushion  2 , have a plurality of through holes  8  that are formed by a predetermined pattern and stitches  9  which are formed at the gap portion between the through hole patterns. In the shown example, a large number of through holes  8  are formed by a pattern in which a quadrangle is formed by one group of through holes  8  which includes four through holes, and stitches  9  are formed into a mesh shape to sew the gap between adjacent quadrangles. 
         [0030]    The pattern of the through holes  8  and the stitches  9  is not limited to the shown example, and the through holes  8  and the stitches  9  may be provided at a surface material that covers other sites of the seat cushion  2  and the seat pack  3 . 
         [0031]      FIG. 2  shows the constitution of the surface material  6 . 
         [0032]    The surface material  6  is formed of an outer material  10  and a wadding material  11  which is laminated on the outer material  10 . The through holes  8  are formed only at the outer material  10 . The stitches  9  are formed across the outer material  10  and the wadding material  11 , and the outer material  10  and the wadding material  11  are sewed together by the stitches  9 . 
         [0033]    It is preferable that the outer material  10  is a material which will not break even if the through holes  8  are formed, and, for example, leather (natural leather, synthetic leather) or a nonwoven fabric is preferred. The wadding material  11  has cushion property, and, for example, resin foam such as soft urethane foam is preferred. 
         [0034]    For the purpose of, such as, reinforcing the surface material  6 , a back material may be further laminated on the wadding material  11 , and in this case, the outer material  10 , the wadding material  11  and the back material are sewed together by the stitches  9 . An appropriate material such as cloth (textile, knitting, and nonwoven fabric) or resin film is used for the back material depending on the purpose. 
         [0035]    The surface material  7  is constructed like the surface material  6 . 
         [0036]      FIG. 3  shows the constitution of a manufacturing apparatus of the surface materials  6 ,  7 . 
         [0037]    The manufacturing apparatus  100  of the surface materials  6 ,  7  includes a drilling apparatus  110  and a sewing machine  120 , which are installed sequentially on a production line, and a jig  130 . The jig  130  is so constructed that the outer material  10  and the wadding material  11  can be held, and is moved from the drilling apparatus  110  to the sewing machine  120 . The movement of the jig  130  may be performed, for example, by a worker and may be performed by a conveyance machine. 
         [0038]    The drilling machine  110  has an installing part  111  where the jig  130  is installed, a head  112  to which a punch for forming through holes is mounted, and a base  113  which supports the installing part  111  and the head  112 . The installing part  111  has a flat table  114  on which the jig  130  is placed and a slider  115  which moves the jig  130  on the table  114  in the X direction and the Y direction. The slider  115  is driven according to a program corresponding to the pattern of the through holes  8  formed at the outer material  10 . 
         [0039]    The sewing machine  120  has a flat installing part  121  on which the jig  130  is placed, a head  122  to which a sewing needle for forming stitches is mounted, and a base  123  which supports the installing part  121  and the head  122 . The installing part  121  has a flat table  124  on which the jig  130  is placed, and a slider  125  which moves the jig  130  on the table in the X direction and the Y direction. The slider  125  is driven according to a program corresponding to the pattern of the stitches  9  formed across the outer material  10  and the wadding material  11 . 
         [0040]    The jig  130 , the slider  115  of the drilling machine  110  and the slider  125  of the sewing machine  120  are provided respectively with engaging parts to position the jig  130  relative the head  112  on the table  114  of the drilling machine  110 , and to position the jig  130  relative to the head  122  on the table  124  of the sewing machine  120 . 
         [0041]    In the shown example, the jig  130  is formed into a roughly rectangular frame shape, and the slider  115  and the slider  125  are respectively formed into a bar-like shape along the outer periphery of one side of the four sides of the jig  130 . The engaging part of the jig  130  is formed of a pair of chucks  136  which are arranged to be spaced at the outer periphery of one side, and which are formed with roughly U-like engaging slots, respectively. The engaging part of the slider  115  is formed of a pair of engaging pins  116  which are fitted and held in the engaging slots of the pair of chucks  136 . The engaging part of the slider  125  is formed of a pair of engaging pins  126  which are fitted and held in the engaging slots of the pair of chucks  136 . 
         [0042]    While the jig  130  and the outer material  10  held on the jig  130  are positioned relative to the head  112  on the table  114  of the drilling machine  110 , when the slider  115  is driven, the head  112  is moved relative to the jig  130 , and the through holes  8  are formed at the outer material  10  by a predetermined pattern. 
         [0043]    While the jig  130  and the outer material  10  and the wadding material  11  which are held by the jig  130  are positioned relative to the head  122  on the table  124  of the sewing machine  120 , when the slider  125  is driven, the head  122  is moved relative to the jig  130 , and the stitches  9  are formed at the outer material  10  and the wadding material  11  by a predetermined pattern. 
         [0044]      FIGS. 4 and 5  show the detailed constitution of the jig  130 . 
         [0045]    The jig  130  has a roughly rectangular first frame  131  which holds the outer material  10  and a roughly rectangular second frame  132  which holds the wadding material  11 . The first frame  131  is placed inside the second frame  132 , and the first frame  131  and the second frame  132  are connected to be openable and closeable through a pair of hinges  135 . 
         [0046]    The four sides of the first frame  131  are provided with clamps  133  which can be opened and closed, respectively, and the first frame  131  holds the outer material  10  by clamping the outer periphery of the outer material  10  between the frame of the first frame  131  and the clamps  133  of the four sides. 
         [0047]    Similarly, the four sides of the second frame  132  are provided with clamps  134  which can be opened and closed, respectively, and the second frame  132  holds the wadding material  11  by clamping the outer periphery of the wadding material  11  between the frame of the second frame  132  and the clamps  134  of the four sides. 
         [0048]    According to the above-mentioned constitution, by rotating the first frame  131  which holds the outer material  10  relative to the second frame  132  to open the first frame  131  and the second frame  132 , without removing the outer material  10  from the first frame  131 , the wadding material  11  can be held by the second frame  132 . Then by closing the first frame  131  and the second frame  132  again, the outer material  10  and the wadding material  11  can be overlapped. 
         [0049]      FIGS. 6A to 6E  show manufacturing processes of the surface materials  6 ,  7  using the manufacturing apparatus  100 . 
         [0050]    At first, as shown in  FIG. 6A , only the outer material  10  is held by the first frame  131  of the jig  130 . Then, as shown in  FIG. 6B , the jig  130  which holds only the outer material  10  with the first frame  131  is installed on the drilling machine  110  of the manufacturing apparatus  100  shown in  FIG. 3 , and the outer material  10  is formed with a lot of through holes  8  by a predetermined pattern. 
         [0051]    Then, as shown in  FIG. 6C , the first frame  131  which holds the outer material  10  is rotated relative to the second frame  132  to open the first frame  131  and the second frame  132 , and the wadding material  11  is held by the second frame  132 . Then, as shown in  FIG. 6D , the first frame  131  which holds the surface material  10  and the second frame  132  which holds the wadding material  11  are closed again, and, the outer material  10  and wadding material  11  are overlapped. 
         [0052]    Then, as shown in  FIG. 6E , the jig  130  which holds the outer material  10  and the wadding material  11  is installed on the sewing machine  120  of the manufacturing apparatus  100  shown in  FIG. 3 , and the outer material  10  and the wadding material  11  are formed with the stitches  9 , which sew the outer material  10  and the wadding material  11  together, at the gap portion between the through hole patterns. 
         [0053]    According to the above method of manufacturing the surface materials  6 ,  7 , after the through holes  8  are formed at the outer material  10  which is held by the jig  130 , the wadding material  11  is held by the jig  130  without removing the outer material  10  from the jig  130 , and then the stitches  9  are formed at the outer material  10  and the wadding material  11  held by the jig  130 . Because continuously from the formation of the through holes  8  until the formation of the stitches  9 , the jig  130  keeps holding the outer material  10 , positioning error of the outer material  10  can be reduced, and misalignment of the stitches  9  and the through hole patterns can be inhibited.