Seat pad foam molding die, seat pad manufacturing method, seat pad and vehicle seat

Abstract

To provide a foam molding die for seat pad in which an opening can be form molded on a side surface of a seat pad in contact with a side surface of a cavity.SOLUTION: A seat pad foam molding die 40 includes: a lower die 42; an upper die 44 forming a cavity 48 between itself and the lower die 42 during clamping; a core 46 disposed in the cavity 48 during the clamping and having a partition part 46A partitioning the inside of the cavity 48; and an elastic body 50 fitted to an end of the partition part 46A and contacting a right side surface 48R of the cavity 48 during the clamping.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a vehicle seat, and more particularly to a seat pad, a foam molding die and a manufacturing method thereof. [Background technology]

[0002] Patent Document 1 below discloses a foam molding die for molding seat pads for vehicle seats, etc. In this foam molding die, a seal member that seals the gap between the mating surfaces of the upper and lower dies is attached to the upper die. This seal member is made of an elastic material such as rubber. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-163347 Summary of the Invention [Problem to be solved by the invention]

[0004] In vehicle seats equipped with side airbag devices, openings such as slits that serve as burst lines may be formed on the side surfaces of the seat pad of the seat back (so-called seat side gusset surfaces). When manufacturing such seat pads, the openings must be formed in post-processing after the foam molding of the seat pad. In other words, due to the structure of the foam molding mold, it is not possible to bring the molds into contact with each other at the side surfaces of the cavity that contact the side surfaces of the seat pad, so the openings cannot be foam molded on the side surfaces of the seat pad, and post-processing is required.

[0005] The present invention aims to provide a foam molding mold for a seat pad that can foam-mold an opening on the side of the seat pad that contacts the side of a cavity, a method for manufacturing a seat pad, a seat pad with a foam-mold opening on the side, and a vehicle seat equipped with such a seat pad. [Means for solving the problem]

[0006] The foam molding mold for the seat pad of the first embodiment comprises a lower mold, an upper mold which forms a cavity between the lower mold and the upper mold when the mold is closed and has a partition which divides the cavity, and an elastic body attached to the tip of the partition which comes into contact with the side of the cavity when the mold is closed.

[0007] In the foam molding mold for the seat pad of the first embodiment, a cavity is formed between the lower mold and the upper mold when the mold is closed. The interior of the cavity is divided by a partition provided in the upper mold. An elastic body is attached to the tip of the partition, and the elastic body comes into contact with the side surface of the cavity when the mold is closed. Therefore, the gap between the side surface of the cavity and the partition surface is blocked by the elastic body. This allows an opening to be foam molded on the side surface of the seat pad that comes into contact with the side surface of the cavity when the seat pad is foam molded in the cavity.

[0008] The foam molding mold for the seat pad of the second embodiment comprises a lower mold, an upper mold that forms a cavity between the lower mold and the upper mold when the mold is closed, a core that is placed in the cavity when the mold is closed and has a partition that divides the cavity, and an elastic body that is attached to the tip of the partition and comes into contact with the side of the cavity when the mold is closed.

[0009] In the foam molding mold for the seat pad of the second embodiment, a cavity is formed between the lower and upper dies when the dies are closed, and a core is placed in the cavity. The cavity is divided by a partition provided in the core. An elastic body is attached to the tip of the partition, and the elastic body comes into contact with the side of the cavity when the dies are closed. Therefore, the gap between the side of the cavity and the partition is blocked by the elastic body. This allows an opening to be foam molded on the side of the seat pad that comes into contact with the side of the cavity when the seat pad is foam molded in the cavity.

[0010] The foam molding die for the seat pad of a third aspect is the first or second aspect, wherein the elastic body is detachable from the tip of the partition portion.

[0011] In the foam molding die for the seat pad of the third aspect, the elastic body is detachable from the tip of the partition portion, so that the elastic body can be replaced when it deteriorates.

[0012] In the method for producing a seat pad of the fourth aspect, the seat pad is produced using the foam molding die of any one of the first to third aspects.

[0013] In the method for manufacturing a seat pad of the fourth aspect, the foam molding die of any one of the first to third aspects is used, and therefore the above-mentioned effects can be obtained.

[0014] The seat pad of the fifth embodiment is made of a foam, and an opening is foam-molded on the side facing outward in the left-right direction of the seat, and the entire inner surface of the opening is a molded surface formed by contact with a foam molding mold.

[0015] In the seat pad of the fifth aspect, the opening formed by foam molding on the side surface facing outward in the left-right direction of the seat has an inner circumferential surface that is formed by contact with the foam molding die. This seat pad can be manufactured by the manufacturing method of the seat pad of the fourth aspect, and therefore the above-mentioned effects can be obtained.

[0016] A vehicle seat of the sixth aspect includes a seat cushion on which an occupant sits, a seat back having the seat pad of the fifth aspect and supporting the back of the occupant, and a side airbag device mounted on the seat back and inflating and deploying a side airbag through the opening in the seat pad.

[0017] In a vehicle seat according to the sixth aspect, the back of an occupant seated on a seat cushion is supported by a seat back. A side airbag device is mounted on the seat back. This side airbag device inflates and deploys a side airbag through an opening in a seat pad provided in the seat back. The seat pad is the same as that of the fifth aspect, and therefore the above-mentioned effects can be obtained. [Effects of the Invention]

[0018] As described above, according to the present invention, openings can be formed by foam molding on the side surfaces of the seat back pad that contact the side surfaces of the cavity. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a side view showing a vehicle seat according to an embodiment; [Figure 2] 1 is a cross-sectional view showing a portion of a seat back of a vehicle seat according to an embodiment of the present invention; [Figure 3] FIG. 2 is a vertical cross-sectional view showing a part of a foam molding die for the seat pad according to the embodiment. [Figure 4] FIG. 10 is a vertical cross-sectional view showing a part of a foam molding die for a seat pad according to a comparative example. [Figure 5] FIG. 10 is a vertical cross-sectional view showing a part of a modified foam molding die for the seat pad according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, a vehicle seat 10 according to one embodiment of the present invention, a seat back pad 24, a foam molding mold 40 for the seat pad, and a method for manufacturing the seat pad will be described with reference to FIGS.

[0021] As shown in Fig. 1, a vehicle seat 10 according to this embodiment includes a seat cushion 12 on which an occupant sits, a seat back 14 that supports the occupant's back, and a headrest 16 that supports the occupant's head. This vehicle seat 10 is, for example, a driver's seat in a so-called right-hand drive vehicle. The seat cushion 12 is attached to a floor F of the vehicle via a slide rail 18. The seat back 14 is connected to the seat cushion 12 via a reclining mechanism 20. The headrest 16 is attached to the upper end of the seat back 14 so that its vertical position can be adjusted.

[0022] 2, the seat back 14 has a seat back frame 22 which is a framework member, a seat back pad 24 which is a cushioning material attached to the seat back frame 22, a side airbag device (side airbag module) 28 attached to the seat back frame 22, a trim cover 30 which covers the seat back pad 24, and a webbing 32 attached to the trim cover 30. The seat back pad 24 corresponds to the "seat pad" in this invention.

[0023] 1 and 2 indicate the front, left, and top directions, respectively, of the vehicle seat 10. Hereinafter, when the vehicle seat 10 is described simply using the front-rear, left-right, top-bottom directions, these directions indicate directions relative to the vehicle seat 10.

[0024] The seatback frame 22 has left and right side frame portions 22A that extend in the up-down direction of the seatback 14 on the left and right sides of the seatback 14, an upper frame portion (not shown) that connects upper ends of the left and right side frame portions 22A in the left-right direction, and a lower frame portion (not shown) that connects lower ends of the left and right side frame portions 22A in the left-right direction. The left and right side frame portions 22A, the upper frame portions, and the lower frame portions are made of, for example, press-formed metal plate material.

[0025] The seatback pad 24 is made of a foam such as polyurethane foam, and is placed over the seatback frame 22 from above. The seatback pad 24 has a main portion 24A that is located in the center of the seatback 14 in the left-right direction and supports the back of the occupant from behind, and a pair of left and right side support portions 24B that are located on the left and right sides of the seatback 14 and support the back of the occupant from the sides. The left and right side support portions 24B protrude forward more than the main portion 24A.

[0026] Each side support portion 24B has a side wall portion 24B1 disposed outward in the left-right direction relative to the corresponding side frame portion 22A at a distance, a front wall portion 24B2 extending obliquely from the front end of the side wall portion 24B1 toward the center and rearward in the left-right direction and connected to the outer left-right end of the main portion 24A, and a rear wall portion 24B3 extending from the rear end of the side wall portion 24B1 toward the center in the left-right direction. A slit 26 extending in the up-down direction of the seat back 14 is formed between the side wall portion 24B1 and the front wall portion 24B2 in a vertically intermediate portion of the right side support portion 24B. This slit 26 corresponds to the "opening" in this invention and opens on the right side surface of the seat back pad 24 (the so-called seat side gusset surface).

[0027] A side airbag device 28 is disposed between the side wall portion 24B1 of the right side support portion 24B and the right side frame portion 22A. This side airbag device 28 includes a bag-shaped side airbag (not shown) made of, for example, a nylon or polyester base fabric, and a cylinder-type inflator (not shown) housed in the side airbag. The side airbag is folded in a predetermined manner, and the inflator is fastened to the right side frame portion 22A with bolts.

[0028] The inflator is activated when a vehicle collision is detected or predicted, and ejects gas into the side airbag, causing the side airbag to inflate and deploy forward. During this deployment, the right side support portion 24B is configured to rupture at the slit 26.

[0029] The trim cover 30 is formed into a bag shape by sewing together multiple pieces of skin made of, for example, cloth, leather, synthetic leather, etc., and is placed over the seatback pad 24 from above. The trim cover 30 has multiple stitching portions, including stitching portions S1, S2, S3, S4, and S5 shown in FIG. 2, as an example. The positions of these stitching portions are determined by the seat design. The stitching portion S1, located on the front end side of the right side support portion 24B, is positioned opposite the slit 26 from the outside in the left-right direction.

[0030] The sewn portion S1 is a burst line when the side airbag inflates and deploys. This sewn portion S1 is a so-called tear seam, and the skin pieces are sewn together with weak thread. When the side airbag inflates and deploys, this sewn portion S1 tears open. This forms an opening in the trim cover 30 that allows the side airbag to deploy outside the seatback 14.

[0031] A webbing 32 is sewn to the sewn portion S1. The webbing 32 is formed in a long strip shape from a cloth-like material that is less stretchy than the base fabric of the side airbag. The webbing 32 is disposed between the right side support portion 24B and the right side frame portion 22A. The webbing 32 is disposed so as to surround the side airbag device 28 when viewed in the up-down direction, with both longitudinal ends inserted through the slits 26 and sewn to the sewn portion S1. The webbing 32 stretches when subjected to the inflation pressure of the side airbag and transmits the inflation pressure of the side airbag to the sewn portion S1. This promotes tearing of the sewn portion S1, stabilizing performance such as the position of the burst line and the deployment speed of the side airbag. The webbing 32 is also configured to regulate the deployment direction of the side airbag.

[0032] Fig. 3 shows a cross-sectional view of a portion of a foam molding die 40 used to foam-mold the seat back pad 24 according to this embodiment. Note that arrows MUP and MLH shown in Fig. 3 indicate the upward and leftward directions of the foam molding die 40, respectively. This foam molding die 40 comprises a lower die 42, an upper die 44, and a core 46. When the lower die 42 and the upper die 44 are clamped together (the state shown in Fig. 3), a cavity 48 is formed between the lower die 42 and the upper die 44, and the core 46 is disposed within this cavity 48.

[0033] The core 46 is provided with a partition 46A that divides the cavity 48. This partition 46A is disposed in the cavity 48 in an area where the right side support portion 24B of the seat back pad 24 is molded. This partition 46A is disposed so as to divide the cavity 48 into an area where the side wall portion 24B1 of the right side support portion 24B is molded and an area where the front wall portion 24B2 of the right side support portion 24B is molded.

[0034] In the mold clamped state shown in Fig. 3, the tip of partition 46A is disposed adjacent to right side surface 48R of cavity 48 and extends in the front-to-rear direction of foam molding mold 40 (the direction perpendicular to the paper surface in Fig. 3). A gap is provided between the tip of partition 46A and right side surface 48R of cavity 48 to prevent direct contact between lower mold 42 and partition 46A (i.e., core 46). This gap is configured to be closed by elastic body 50 attached to the tip of partition 46A.

[0035] Elastic body 50 is made of synthetic rubber, elastomer, or the like, and is heat-resistant enough to withstand temperatures of 70°C or higher. Elastic body 50 is formed in an elongated shape, and extends in the front-to-rear direction of foam molding die 40 (the direction in which the tip of partition 46A extends) when in the clamped state shown in Fig. 3. Elastic body 50 is fixed to the tip of partition 46A by means of, for example, bolting or fitting, and is detachable from partition 46A.

[0036] The elastic body 50 has a generally triangular shape when viewed in the longitudinal direction (the direction perpendicular to the paper surface in FIG. 3) like a wiper blade, and is formed so that its width narrows toward the tip side (the side of the right side surface 48R of the cavity 48). In the mold clamped state shown in FIG. 3, the tip of the elastic body 50 contacts the right side surface 48R of the cavity 48, and the elastic body 50 is configured to undergo elastic deformation.

[0037] In the method for manufacturing a seat pad according to this embodiment, the seat back pad 24 is manufactured using the foam molding die 40. During this manufacturing process, a liquid material for a flexible foam is injected into the lower die 42 using an injector (not shown), and then the upper die 44 is closed and the liquid material is foamed and filled into the cavity 48. As a result, the slit 26 is foam-formed in the right side support portion 24B of the foam-molded seat back pad 24 at a location corresponding to the elastic body 50 and the tip of the partition portion 46A. The slit 26 has a configuration in which the entire inner circumferential surface is molded by contact with the elastic body 50 and the tip of the partition portion 46A (i.e., the foam molding die 40).

[0038] Next, the operation and effects of this embodiment will be described. In the vehicle seat 10 according to this embodiment, the back of an occupant seated on the seat cushion 12 is supported by the seat back 14. A side airbag device 28 is mounted on the seat back 14. The side airbag device 28 inflates and deploys a side airbag through a slit 26 in the seat back pad 24.

[0039] When the foam molding die 40 for foam-molding the seat back pad 24 is closed, a cavity 48 is formed between the lower die 42 and the upper die 44, and a core 46 is placed in the cavity 48. The cavity 48 is divided by a partition 46A provided in the core 46. An elastic body 50 is attached to the tip of the partition 46A, and when the die is closed, the elastic body 50 comes into contact with a right side surface 48R of the cavity 48. Therefore, the gap between the right side surface 48R of the cavity 48 and the partition 46A is blocked by the elastic body 50. As a result, in the seat back pad 24 foam-molded in the cavity 48, a slit 26 can be foam-molded in the right side surface that contacts the right side surface 48R of the cavity 48.

[0040] The above-mentioned effects will be further explained using a comparative example shown in FIG. 4. In the foam molding die 100 according to this comparative example, the elastic body 50 is not attached to the tip of the partition portion 46A of the core 46, and a gap 102 is formed between the tip of the partition portion 46A and the right side surface 48R of the cavity 48 when the die is closed. However, the other configurations are the same as those of the foam molding die 40 according to this embodiment. When foam molding the seat back pad 24 with this foam molding die 100, the slits 26 cannot be formed by foam molding alone, so post-processing is required to form the slits 26. Variations due to manual processing in this post-processing affect the deployment performance of the side airbag, so post-processing must be performed carefully to prevent variations, which increases the number of steps and increases manufacturing costs.

[0041] On the other hand, if the foam molding mold 100 is configured so that the tip of the partition 46A directly contacts the right side surface 48R of the cavity 48, the slit 26 can be formed by foam molding alone. However, if the position of the core 46 varies relative to the lower mold 42, the upper mold 44 may not close or the foam molding mold 100 may be damaged. Furthermore, when a large number of seat back pads 24 are manufactured, the contact point of the tip of the partition 46A with the right side surface 48R of the cavity 48 may be worn away, making the shape of the slit 26 unstable. As a result, performance such as the position of the burst line and the deployment speed of the side airbag may become unstable.

[0042] Furthermore, when the position of the slit 26 is set to the front surface of the side support portion 24B, the tip of the partition portion 46A can be brought into direct contact with the underside of the cavity 48, allowing the two to be brought into contact with precision and eliminating the above-mentioned scraping problem. However, this requires changing the position of the stitching portion S1 of the trim cover 30 to the front side of the side support portion 24B, which places restrictions on the design of the seat back 14 (the position of the stitching line).

[0043] In this regard, in this embodiment, the elastic body 50 attached to the tip of the partition portion 46A of the core 46 contacts the right side surface 48R of the cavity 48 and elastically deforms, so opening and closing of the foam molding die 40 is not hindered and the problem of scraping of the core 46 and the lower die 42 is also eliminated. Moreover, post-processing to form the slit 26 is not required, so manufacturing costs can be reduced. In addition, restrictions on the position of the slit 26 are reduced, allowing for more precise adjustment of the burst line of the seat back 14, which stabilizes the deployment performance of the side airbag. Furthermore, restrictions on the position of the stitching line of the seat back 14 are reduced, so the degree of freedom in designing the seat back 14 is improved.

[0044] Furthermore, in this embodiment, the elastic body 50 is detachable from the tip of the partition portion 46A, so that the elastic body 50 can be replaced when it deteriorates.

[0045] In the above embodiment, the foam molding mold 40 includes a core 46, and the elastic body 50 is attached to the tip of the partition 46A provided on the core 46, but the present invention is not limited to this. For example, if the foam molding mold 60 does not include a core 46 and the partition 44A that separates the interior of the cavity 48 is provided on the upper mold 44 of the foam molding mold 60, as in the modified example shown in Figure 5, the elastic body 50 may be attached to the tip of the partition 44A of the upper mold 44. In this case, the elastic body 50 attached to the tip of the partition 44A of the upper mold 44 comes into contact with the side surface 48R of the cavity 48 when the molds are clamped.

[0046] In addition, the present invention can be implemented with various modifications within the scope of the gist thereof. Furthermore, it goes without saying that the scope of the rights of the present invention is not limited to the above-described embodiment. [Explanation of symbols]

[0047] 10 Vehicle seats 12 seat cushions 14 Seat back 24 Seat back pad (seat pad) 26 Slit (opening) 28 Side airbag device 40 Foam molding mold 42 Lower mold 44 Upper mold 44A Partition 46 Core 46A Partition 48 Cavity 48R Right side (side) 50 Elastic Body 60 Foam molding mold

Claims

1. Lower mold and an upper mold that forms a cavity between itself and the lower mold when the molds are clamped, and has a partition that divides the cavity; an elastic body attached to the tip of the partition portion and contacting the side surface of the cavity when the mold is closed; Foam molding mold for seat pad.

2. Lower mold and an upper mold that forms a cavity between itself and the lower mold when the molds are clamped; a core that is placed in the cavity when the mold is clamped and has a partition that divides the cavity; an elastic body attached to the tip of the partition portion and contacting the side surface of the cavity when the mold is closed; Foam molding mold for seat pad.

3. 3. The foam molding mold according to claim 1, wherein the elastic body is detachable from the tip of the partition portion.

4. A method for manufacturing a seat pad, using the foam molding mold according to claim 1 or 2.

5. A seat pad made of a foam material, with an opening foam-molded into the side facing outward in the left-right direction of the seat, and the entire inner surface of the opening being a molded surface formed by contact with a foam molding mold.

6. A seat cushion on which an occupant sits; a seat back having the seat pad according to claim 5 and supporting the back of the occupant; a side airbag device mounted on the seat back and configured to inflate and deploy a side airbag through the opening in the seat pad; A vehicle seat comprising:

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