JP2006020736A - Manufacturing method of cushion pad and mold used therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent breakage in a resin foam body when opening a mold or taking it out in a manufacturing method of seat cushion pad used for a vehicle seat or others such as an automobile and the mold used therefor. <P>SOLUTION: The mold 1 for molding the cushion pad is provided with a bridge structure or a projecting structure 18 extending from the wall surface of a bottom mold 11 to the wall face of a core mold 12 in its inside for providing a through slit in the cushion pad. In this case, the projecting structure 18 is formed by butting a projection 16 from the bottom mold 11 on a projection 17 from the core mold 12. The projections 16 and 17 have almost equal projecting dimension and are disposed along the turning direction when opening the mold. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a cushion pad for a seat used for a vehicle seat such as an automobile and the like, and a mold used therefor. In particular, the present invention relates to a method of manufacturing a cushion pad having a slit or a penetrating portion, and a mold used therefor.

  A cushion pad made of an elastic resin foam is disposed on the seat portion and the backrest portion of the vehicle seat that receives vibration when the vehicle travels, in order to reduce transmission of vibration to the occupant and to maintain a good ride comfort.

  In recent years, safety requirements have become stricter, and a side airbag device for protecting an occupant not only in front of the occupant but also in the event of a side collision has come to be mounted. Therefore, for example, a side airbag device is arranged on the back side of the side portion of the cushion pad for the seat, and a slit penetrating the cushion pad or a fragile portion that easily ruptures under the deployment pressure of the airbag is provided. Has been proposed (Japanese Patent Laid-Open No. 9-254735).

  In addition, an attempt has been made to obtain a resin foam having different physical properties for each part by providing a partition in a cavity in a mold and charging two or more kinds of foamed resin raw materials into each of the divided cavities ( JP 2000-000133).

  In order to form such a cushion pad, it has been proposed to use a mold 1 'as schematically shown in FIG. That is, it has been proposed to provide a plate-like protrusion structure 18 ′ extending to the wall surface of the lower mold 11 on the wall surface of the upper mold 13.

On the other hand, another type of resin foam having a small diameter is inserted in a mold for forming a cushion pad, and thereby, the elasticity of a specific part is made different from that of other parts (Japanese Patent Application Laid-Open (JP-A)). 2001-170948). Here, in order to fix the resin foam as an insert in the mold, it is disclosed that a rod-like protrusion protruding from the wall surface of the mold into the cavity is provided and pierced into the hole of the resin foam. ing.
JP-A-9-254735 JP 2000-000133 A JP 2001-170948 A

  When a cushion pad is molded using a mold having a protruding structure into the cavity as described above, the resulting resin foam may be torn when the mold is opened due to the protruding structure. there were. When the mold is opened, the upper mold and the core mold are usually rotated around one axis fixed to the lower mold. That is, the mold is opened in such a way as to open a bivalve shell. During this rotation, the protrusion structure protruding from the wall surface of the mold locally gives a large deformation to the resin foam in the mold.

  The present invention has been made in view of the above problems, and in a method for manufacturing a cushion pad having a slit or a through portion and a mold used therefor, the resin foam is torn when the mold is opened or taken out. Try to provide something that can prevent.

  The manufacturing method of the cushion pad for seats of the present invention reaches the wall surface of the first mold part, the second mold part, and the wall surface of the second mold part from the wall surface of the first mold part. A resin is foamed inside a mold having a protruding structure, thereby forming a resin foam having a slit or a through-hole, and after molding, the first and second mold parts are A method of manufacturing a cushion pad including the step of rotating each other around an axis substantially perpendicular to the protrusion structure and thereby taking out the resin foam, wherein the protrusion structure includes a protrusion of the first mold portion; It consists of a combination with the projection of the second mold part.

  In a preferred embodiment, the protrusion of the first mold part and the protrusion of the second mold part are substantially equal in protrusion dimension. If it is like this, the deformation | transformation which arises locally in the resin foam at the time of mold opening and taking out can be minimized.

  In a particularly preferred embodiment, the protrusions of the first mold part and the protrusions of the second mold part both extend linearly in a cross section perpendicular to the axis, and slightly at the combination point. Bends. The bending is performed in a direction in which the bent portion protrudes toward the shaft, and the angle of bending is 1 to 5 °, preferably 2 to 3 °. As such, local deformation and stress at the time of mold opening and removal can be further reduced, and the occurrence of tearing can be more reliably prevented.

  The mold used for molding the cushion pad for seat according to the present invention includes a first mold part, a second mold part, and a wall surface of the second mold part from a wall surface of the first mold part. And a support structure for supporting the first and second mold parts so that the mold can be opened by rotating around a substantially vertical axis with respect to the protrusion structure. In the mold, the protrusion structure is a combination of a protrusion of the first mold part and a protrusion of the second mold part.

  When the mold is opened, the resin foam can be prevented from being broken. Moreover, the operation which takes out the resin foam from a metal mold | die can be performed more easily.

  An embodiment of the present invention will be described with reference to FIGS.

  1 and 2 are schematic cross-sectional perspective views of a mold according to an embodiment, and the mold is shown in a closed state and an open state, respectively. These drawings are shown upside down, and the lower mold is drawn upward. The mold 1 includes a dish-shaped lower mold 11, a core mold 12, and a frame-shaped upper mold 13 arranged so as to surround the core mold 12. These mold parts 11, 12, and 13 are rotatably supported from one shaft 14 via respective support parts 11A, 12A, and 13A. That is, the base portion of each of the support portions 11A, 12A, and 13A forms a hinge that is supported by the shaft 14, so that the mold portions 11, 12, and 13 can rotate around the shaft 14. . At the time of mold opening, the core mold 12 and the upper mold 13 are lifted by driving means (not shown), and the mold 1 is opened in a two-shell shape (FIG. 2).

  As shown in FIGS. 1 and 2, in the mold 1, the protrusion 16 from the wall surface of the lower mold 11 and the wall surface of the core mold 12 are formed at one place along the opposite ridge line of the shaft 4. A protrusion 17 is provided. When the mold 1 is closed, the tip surfaces of the protrusions 16 and 17 are closely abutted to form one bridge structure or one protrusion structure 18 extending from the wall surface of the lower mold 11 to the wall surface of the core mold 12. ing. These protrusions 16 and 17 are in the form of a flat plate extending in a direction substantially parallel to the shaft 14, and in a cross section perpendicular to the shaft 14 (the cross section shown in the drawing), the protrusions 16 and 17 are arranged substantially in the tangential direction of a circle centering on the shaft 14. ing. This is to prevent scratch deformation from being applied to the resin foam filling the cavity 15 at the time of mold opening after foam molding.

  In the example shown in the drawing, the protrusions 16 and 17 are slightly shifted from each other in the linearly extending direction when viewed in a cross section perpendicular to the shaft 4. If exaggerated, the protrusions 16 and 17 protrude toward the shaft 4 side. "". This is for further reducing the scratch deformation applied to the resin foam during mold opening after foam molding. In the specific example shown in the drawing, the lengths of the flat protrusions 16 and 17 along the shaft 4 are greatly different from each other, and the protrusion 17 of the core mold 12 is longer. Therefore, the slit is long on the back side and short on the front side. This is for facilitating the deployment of the airbag from the airbag device and minimizing the influence of the slit on the surface side.

  FIG. 3 is a cross-sectional perspective view of the cushion pad 2 obtained by the manufacturing method of the embodiment, corresponding to FIGS. FIG. 4 schematically shows the overall appearance of the cushion pad 2. The cushion pad 2 is made of the resin foam 21 molded in the mold 1 and includes a slit 22 formed by the protruding structure 18. In addition, the cushion pad 2 has a substantially rectangular parallelepiped concave fitting portion on the back side of the slit 22, and the airbag device 3 is attached to this portion.

  As schematically shown in FIG. 3, the airbag device 3 includes a gas generator 31 for airbag deployment inside, and an airbag 32 made of cloth or the like is folded in a case 33 made of plastic or the like. Is stored. When a collision from the side of the vehicle is detected, that is, when a gravitational acceleration of a predetermined value or more is detected in the left-right direction of the vehicle, gas is generated explosively from the gas generator 31. This gas spreads the air bag 32 and presses the portion of the slit 22 through the opening of the case 33 or while opening the planned damaged portion of the case 33. Then, the resin foam 21 is torn along the slit 22 while the slit 22 is opened in a round shape, and the airbag 32 is deployed to the front side of the cushion pad 2.

  The front side surface of the cushion pad 2, that is, the portion exposed to the outside when mounted on the vehicle, is entirely covered with a skin 23 made of fabric, leather, artificial leather or the like. In the illustrated example, the skin 23 has a predetermined opening portion along the slit 22 so as to easily form an opening when the airbag is deployed. That is, the skin 23 is provided with a cut, and its edge is overlapped at the slit 22.

  The skin 23 of the cushion pad 2 may be attached after the resin foam 21 is molded, or may be disposed as an insert in the lower mold 11 and bonded together during foam molding. Also good.

  In the above-described embodiment, the protrusion 17 combined with the protrusion 16 of the lower mold 11 is described as the protrusion from the core mold 12, but the protrusion 17 corresponding to the upper mold 13 is provided depending on the shape of the cushion pad. Moreover, in the said Example, although demonstrated as what forms a slit in flat form for the expansion | deployment of a side airbag, it may be for providing the penetration part of another form. For example, a large number of through-holes may be provided in a row to form a fragile portion that is torn and opened when the side airbag is deployed.

  The partition wall is not limited to the slit for the side airbag, and may be a partition wall for dividing the cavity in the mold into a plurality of sections in order to change the resin composition at a specific portion of the cushion pad. Moreover, the protrusion structure provided in order to hold | maintain various inserts may be sufficient.

It is a typical section perspective view shown in the closed state about a metallic mold of an example. It is a typical section perspective view showing the opened state about the metallic mold of Drawing 1. It is a typical section perspective view showing a cushion pad obtained by a metallic mold of an example. It is a typical perspective view which shows the whole external appearance about the cushion pad obtained by the metal mold | die of an Example. It is a typical fragmentary sectional perspective view for demonstrating the principal part of the structure of the metal mold | die of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mold 11 Lower mold 12 Core mold 13 Upper mold 14 Shaft of mold 1 15 Cavity 16 Projection from wall surface of lower mold 11 17 Projection from wall surface of core mold 12 18 Bridge by combination of projections 16 and 17 Or projection structure 2 Cushion pad 21 Resin foam forming cushion pad 2 22 Slit for airbag 3 23 Cushion pad skin 3 Airbag device 32 Airbag

Claims (4)

Resin is placed inside the mold having a first mold part, a second mold part, and a protruding structure that extends from the wall surface of the first mold part to the wall surface of the second mold part. Foaming, thereby forming a resin foam with slits or through holes; and
After the molding, the first and second mold parts are rotated with respect to each other around an axis substantially perpendicular to the protruding structure, thereby taking out the resin foam.
The method of manufacturing a cushion pad, wherein the protrusion structure is a combination of a protrusion of the first mold part and a protrusion of the second mold part.   2. The method of manufacturing a cushion pad according to claim 1, wherein the protrusion of the first mold part and the protrusion of the second mold part are substantially equal in protrusion dimension.   The projections of the first mold part and the projections of the second mold part both extend linearly in a cross section perpendicular to the axis, and are slightly bent at the combination part. The manufacturing method of the cushion pad of Claim 1. A first mold part, a second mold part, and a protruding structure reaching from the wall surface of the first mold part to the wall surface of the second mold part;
A mold having a support structure for supporting the first and second mold parts so that the mold can be opened by rotating with respect to each other about an axis substantially perpendicular to the protruding structure;
The mold characterized in that the projection structure is a combination of a projection of the first mold part and a projection of the second mold part.

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