JP2005178147A - Seat pad manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seat pad manufacturing method capable of satisfying required capacities by preventing the positional shift of a net made of a synthetic resin when a seat pad having the net embedded therein is manufactured. <P>SOLUTION: A mold 6 is equipped with a lower mold 60 for molding the surface side of the seat pad 1 and an upper mold 61 for molding the rear side of the seat pad 1 and characterized in that a locking projection 7 downward projected into the mold is provided to the upper mold 61. This mold 6 is used to lock the net 3 made of a synthetic resin with the leading end of the locking projection 7 to mount the net 3 in the mold 6 in a state leaving a predetermined distance from the upper mold 61. Subsequently, a soft foam raw material M is injected in the mold 6 and foamed in the hermetically closed mold 6 to be integrated with the net 3. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a seat pad, and more particularly, to a method for manufacturing a seat pad suitable for a seat for a vehicle such as an automobile that vibrates during use.

  Generally, cushion pads made of soft polyurethane foam with high cushioning properties are used for automobile seats, and this is placed on a support frame and covered with a skin on the surface of the pad, etc. Has been.

  In such a vehicle seat, it is required to lower the vehicle height due to demands for improving the fuel efficiency due to the design of the body and the reduction of the air resistance value. For this reason, the cushion pad may be required to be thinner. In addition, recently, due to the diversification of prime movers and fuels and the demand for expanding the luggage space, the fuel tank can be placed under the seat. In order to improve the storability, it is required to make the cushion pad thinner.

  However, especially when the cushion pad is made thinner, when the lower surface of the seating part is used as a support frame in combination with a support frame that is elastically supported by a spring, a firm feeling at the bottom of the buttocks that supports the seated buttock (holding property) Inferior to Such a tendency tends to become more prominent as the polyurethane foam constituting the cushion pad is softened in order to ensure the flexibility at the initial load. Therefore, in the prior art, particularly when the cushion pad is thinned, it has been difficult to exert a firm feeling in the lower part of the buttocks in the high load region while ensuring the flexibility in the initial load region.

  By the way, the following Patent Document 1 proposes a cushion structure in which a three-dimensional net is embedded in a pad material in order to secure a predetermined cushioning property, which is inexpensive, thin and light, has various spring constants. . However, in this Patent Document 1, the three-dimensional net is only foamed integrally with the pad material, and it is not disclosed how to embed the three-dimensional net in the pad material.

  When embedding this type of net in the pad material, if the net is not accurately positioned in the pad material and a deviation occurs, the seat pad characteristics will be affected, making it impossible to satisfy the required performance. Therefore, how to position the net is extremely important in practice.

Moreover, in the said patent document 1, although the net | network embed | buried in pad material is using the three-dimensional structure of the 3 layer structure which consists of an upper mesh layer, a lower mesh layer, and the pile layer which couple | bonds these, In the net having such a three-layer structure, there is a possibility that the polyurethane foam is not uniformly filled inside the net, and if voids are generated in the intermediate layer of the pad, the above-mentioned firm feeling cannot be fully exhibited.
JP 2000-217658 A

  The present invention has been made in view of the above points, and when manufacturing a seat pad in which a synthetic resin net is embedded, the positional displacement of the net can be prevented and the required performance can be satisfied. An object of the present invention is to provide a method for manufacturing a seat pad.

  The seat pad manufacturing method of the present invention is a seat pad manufacturing method in which a synthetic resin net is embedded inside, a lower mold for molding the front side of the seat pad, and an upper mold for molding the back side of the seat pad; And a synthetic resin net is locked to the tip of the locking projection using a molding die provided with a locking projection protruding downward into the molding die on the upper mold. The net is mounted in the mold with a predetermined distance from the upper mold, and then the flexible foam material is injected into the mold, and the flexible foam material is injected into the sealed mold. It is foam-filled and integrated with the net.

  Since the seat pad obtained in this way has a synthetic resin net embedded therein, by supporting the load of the seated person with this net, it is possible to exert a firm feeling in a high load range. . And since the surface consists of a flexible foam, the flexibility in an initial load area is ensured and a soft surface feel is not impaired. And according to the present invention, the net is held in the mold by the locking projection provided on the upper mold, and the flexible foam raw material is foam-filled in this state. Can be satisfied. In addition, since the locking protrusion is provided on the upper mold side for molding the pad back surface side, a hole formed in the seat pad by the locking protrusion also appears on the pad back surface side. Will not be damaged.

  In the present invention, the net is preferably a single-layer net composed of a single mesh layer. By using such a single-layer net, it is possible to suppress the generation of voids in the pad due to the net and to fully exhibit a firm feeling in a high load region. In addition, the single-layer net is generally less expensive than the conventional three-dimensional net, so that the cost of the seat pad is excellent.

  According to the present invention, it is possible to prevent a positional shift of a synthetic resin net embedded in a seat pad, satisfy a required performance such as a firm feeling in a high load range, and obtain a comfortable sitting comfort. it can.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 is a cross-sectional view of a molding die at the time of manufacturing a seat pad according to an embodiment of the present invention, FIG. 2 is a perspective view of the molding die, FIG. 3 is a partially enlarged view thereof, and FIG. FIG. 6 is a longitudinal sectional view (a sectional view corresponding to line IV-IV in FIG. 5) of the support frame that supports the seat pad, and FIG. 6 is a plan view of the seat pad.

  The seat pad 1 of the present embodiment is a seat cushion pad used for an automobile seat, and a synthetic resin net 3 is embedded as an intermediate layer inside a pad main body 2 made of a flexible polyurethane foam.

  As shown in FIG. 5, the seat pad 1 is composed of a seating portion 11 in the center in the width direction and side portions 12 and 12 formed in a protruding shape on both the left and right sides, and on the pad surface (upper surface), A pair of left and right vertical grooves 13, 13 extending in the front-rear direction along the boundary between the seating portion 11 and the side portion 12 are provided, and left and right so as to connect the center portions in the front-rear direction of the left and right vertical grooves 13, 13. A lateral groove 14 extending in the direction is provided, and as a result, a groove is formed in a substantially H shape on the entire pad surface. The seat portion 11 is divided into front and rear by the lateral groove 14, and the front side of the lateral groove 14 receives and supports the thigh of the seated person, and the rear side of the lateral groove 14 receives and supports the seated person's buttocks. It is 16.

  In addition, at the seating part 11 of the cushion pad 1, more specifically, at the hip point 17 (the point corresponding to the center of rotation of the torso and thigh of the human body mannequin when seated on the seat by JASO Z-221). The pad thickness is preferably set to 30 to 70 mm. This thickness is thinner than the conventional general cushion pad thickness of about 80 mm, and the present invention is particularly effective when applied to such a thinner cushion pad.

  The material of the synthetic resin net 3 is not particularly limited, but is preferably made of polyolefin such as polypropylene. In this embodiment, a polypropylene net is used. Further, in this embodiment, as shown in FIG. 3, a single layer net composed of a single mesh layer is used as the net 3, and more specifically, the net 3 is composed of a lattice mesh layer. .

  As shown in FIGS. 4 and 5, the net 3 has a rectangular shape, and is disposed substantially horizontally at an intermediate position in the thickness direction at the bottom portion 16 of the pad body 2. Specifically, the net 3 is disposed only in the middle layer of the bottom part 16 and is not disposed in the thigh receiving part 15 or the side part 12. Thus, even when the seat pad 1 is thinned by putting the net 3 in the intermediate layer of the bottom part 16, the surface feel is soft, but the firm feeling in the bottom part 16 in the high load area is exhibited. , You can get a comfortable sitting and riding comfort.

  A reinforcing cloth 4 as a backing material is laminated on the back surface (bottom surface) of the seat pad 1 over the entire surface. The reinforcing cloth 4 is provided to prevent damage to the pad main body 2 due to friction with the support frame 5 and to prevent abnormal noise due to friction with the support frame 5.

  The seat pad 1 is placed on a metal support frame 5 and further covered with a non-illustrated skin to constitute a vehicle seat. Here, the support frame 5 has a substantially rectangular shape corresponding to the lower surface portion of the seat pad 1. As shown in FIG. 4, the support frame 5 has a front receiving surface portion 51 having rigidity for receiving the lower surface of the front portion of the seat pad 1. , A so-called semi-spring type frame including a spring 52 which is provided behind and elastically supports the lower surface of the bottom portion 16 of the seat pad 1.

  As shown in FIGS. 1 and 2, the molding die 6 for molding the seat pad 1 is capable of opening and closing the concave lower mold 60 that is held substantially horizontally and molds the pad surface side, and the upper surface opening of the lower mold 60. And an upper mold 61 that molds the back side of the pad. By closing both of the molds, a foam molding space 62 corresponding to the shape of the seat pad 1 is formed inside the mold 6. The upper mold 61 is provided with a plurality of pins 63 for mounting the reinforcing cloth 4 along the mold surface. Further, the upper mold 61 is provided with a locking projection 7 projecting downward to hold the net 3 in the foam molding space 62.

  As shown in FIG. 2, the four locking projections 7 are arranged so as to lock each corner of the rectangular net 3. Further, the four locking projections 7 have respective tips at their ends so as to hold the net 3 approximately horizontally at a position separated from the mold surface of the upper mold 61 by locking the four corners of the net 3. A locking portion 70 for hooking the net 3 is provided. Specifically, as shown in FIG. 3, the locking protrusion 7 includes a columnar body 71 that protrudes downward substantially perpendicularly from the mold surface of the upper mold 61, and the columnar body 71 that extends downward from the front end surface thereof. And a tapered portion 73 that is tapered toward the tip that protrudes downward from the net 3 and prevents the net 3 from being displaced downward. The mesh of the net 3 is formed by the small-diameter portion 72 and the tapered portion 73. A locking portion 70 is configured to be hooked and stopped. The length of the columnar body 71 can be set as appropriate depending on the arrangement position of the net 3 in the thickness direction of the seat pad 1. In this embodiment, the net 3 is positioned at a substantially intermediate position in the thickness direction of the seat pad 1. In order to be embedded in the upper die 61, the lower die 60 and the upper die 61 are extended to a substantially intermediate position.

  When the seat pad 1 is manufactured using the molding die 6, the reinforcing cloth 4 is first attached to the upper die 61 with the pins 63 with the upper die 61 opened as shown in FIG. 2. At that time, as shown in FIG. 3, the reinforcing cloth 4 is provided with a through hole 41 at a position corresponding to the locking protrusion 7, and the reinforcing protrusion 4 is passed through the through hole 41. Set on the upper mold 61.

  Next, the net 3 is set on the upper mold 61 using the locking protrusions 7. At that time, if the net 3 is pulled slightly and the locking portion 70 at the tip end of the locking projection 7 is inserted into the mesh at the four corners, the net 3 can be held securely, and the net 3 is shown in FIG. As described above, the upper mold 61 is set substantially horizontally in a state of being separated from the mold surface.

  Thereafter, after the polyurethane foam raw material M is injected into the lower mold 60, the upper mold 61 is closed, and the polyurethane foam raw material M is foam-filled in the sealed foam molding space 62. Thereby, foam molding is performed in a state where the net 3 is embedded in the seat pad 1 integrally. At this time, in the present embodiment, since the net 3 is stably held by the locking projection 7, there is no positional deviation of the net 3 at the time of foam molding, so that the performance of the net 3 described above can be stabilized. It can be demonstrated. More specifically, the downward displacement of the net 3 is limited by the upper end portion of the tapered portion 73 once having a large diameter from the small diameter portion 72, and the upward displacement of the net 3 due to the pushing up of the polyurethane foam is the small diameter portion. It is limited by the step between 72 and the columnar body 71. Further, since the net 3 has a single-layer structure, the polyurethane foam is reliably filled and foamed around the net 3, and no voids are generated, so that a firm feeling in a high load region is not impaired.

  After foaming in this manner, the upper die 61 is opened and the molded seat pad 1 is removed. In the obtained seat pad 1, a hole by the locking projection 7 is formed on the back surface side, but since a hole by the locking projection 7 is not formed on the pad surface side, the pad The design of the surface side is not impaired.

It is sectional drawing of the shaping | molding die at the time of manufacture of the seat pad which concerns on embodiment. It is a perspective view of the same mold. It is a partially expanded perspective view of the same mold. It is a longitudinal cross-sectional view of the seat pad and a support frame. It is a top view of the seat pad.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Seat pad 2 ... Pad main body 3 ... Synthetic resin net 4 ... Reinforcement cloth 5 ... Support frame 6 ... Molding die 60 ... Lower die 61 ... Upper die 7 ... Locking protrusion

Claims (2)

In the manufacturing method of a seat pad with a synthetic resin net embedded therein,
A locking mold that includes a lower mold that molds the front side of the seat pad and an upper mold that molds the back side of the seat pad, and that protrudes downward from the upper mold toward the molding mold. Using a mold provided with
A net made of synthetic resin is locked to the tip of the locking protrusion, and the net is mounted in the mold with a predetermined distance from the upper mold,
Then, a flexible foam raw material is injected into the mold, and the flexible foam raw material is foam-filled in a sealed mold to be integrated with the net.   The seat pad manufacturing method according to claim 1, wherein the net is a single-layer net composed of a single mesh layer.

Images