JP5242339B2 - Molding method of different hardness pad and foaming mold used for the molding - Google Patents

Description

  The present invention relates to a method for molding a polyurethane foam different hardness pad using a breathable block and a foam molding die thereof, and more particularly, to molding a different hardness pad using a block formed of a resin foam chip. The present invention relates to a method and its foaming mold.

  As a seat cushion or seat back for an automobile seat, a polyurethane foam obtained by injecting a polyurethane raw material into a foam mold and reinforcing the foam with a frame or the like and covering with a skin material is generally used. In recent years, automobile seats have been designed so that the thighs are not subjected to loads during driving operations, the posture of the passengers is maintained against the lateral acceleration experienced during driving, and fatigue is caused by prolonged driving. In order to prevent the accumulation of heat, a different hardness pad having a partially different hardness is employed. Furthermore, an example of a different hardness pad for the purpose of shock absorption is also disclosed.

  The “method of forming a different hardness seat pad” disclosed in Patent Document 1 is such that the hardness of the side portions on both sides of the seating portion is higher than the hardness of the seating portion of the seat cushion of the automobile seat. Thus, the present invention relates to a method for forming a different hardness seat pad that makes it difficult for the occupant to collapse. According to this molding method, when the slab material is set at the left and right side portion forming portions of the pad on the cavity surface of the upper mold in the foam mold, the polyurethane material breaks up when the injected polyurethane material expands and expands. Foam gas is released from the back surface of the slab material through the exhaust pipe so that the surface of the slab material can be easily impregnated. Therefore, the polyurethane raw material is impregnated on the surface of the slab material, and an impregnation layer harder than the seating portion is formed.

  The “method for manufacturing a seat back for automobiles” disclosed in Patent Document 2 uses a foaming mold including a lower mold, an upper mold, and a middle mold disposed between the lower mold and the upper mold. When manufacturing a seat back for an automobile seat, a shock absorbing material is inserted into a middle mold for forming both side portions of the seat back to manufacture a pad with different hardness. According to this manufacturing method, the shock absorber is attached to the middle mold by fitting the concave portions of the shock absorber made of hard urethane foam to the protrusions formed on both sides of the middle mold. At that time, a back surface reinforcing material is sandwiched between the shock absorbing material and the middle mold.

The “seat pad” disclosed in Patent Document 3 is obtained by embedding and integrating a bag filled with a granular foam in a polyurethane foam. The bag body is covered with a non-breathable skin on the surface that contacts the polyurethane, and the other surface is covered with a breathable skin, so that the polyurethane raw material is prevented from entering the bag body, Air inside the bag can be circulated to the outside. Further, it is said that by adjusting the particle size and density of the granular foam, it is possible to adjust the hardness of the bag body whether it is hard or soft.
Japanese Patent Laid-Open No. 5-422 (see [Summary], paragraph [0008] of the specification) JP-A-9-70836 (see [Summary] and [FIG. 3]) JP 2003-189972 A (see [Summary], [Claims], paragraph [0034] of the specification)

  In general, in the molding of polyurethane foam, depending on the size and shape of the insert material inserted into the foam mold, or the relationship between the position where the polyurethane raw material is injected and the position where the insert material is set in the foam mold, etc. A recess may be formed around the material due to gas accumulation.

  In the molding method of Patent Document 1, the gas in the slab material can be released out of the mold through the exhaust pipe, so that no gas can be accumulated around the slab material. However, when the polyurethane material impregnation layer is formed on the surface of the slab material, the hardness is adjusted by controlling the amount of gas escaped by using the exhaust pipe. The device for controlling the timing and quantity is not simple, and the problem of increased equipment costs is inevitable.

  In the manufacturing method of Patent Document 2 using a shock absorber made of hard urethane foam, the shock absorber is foam-molded using a mold and has a high-density skin layer on the surface. The polyurethane raw material is rarely impregnated with the gas, and gas hardly leaks from the inside of the shock absorbing material. Therefore, in this manufacturing method using the shock absorbing material, it is difficult for a gas pool to occur around the shock absorbing material, and the possibility of forming a recess due to the gas pool is small.

  The bag body filled with the granular foam of Patent Document 3 is covered with a non-breathable film on the surface in contact with the polyurethane raw material, and the other surface is covered with a breathable sheet. Therefore, the bag body is more expensive than a simple granular foam block. In addition, there is no mention of the problem that a recess due to a gas reservoir is formed around the bag body.

  In general, using a block with a resin foam chip bonded, a different hardness pad that is harder than the foam around the block is formed as a resin foam chip when molding the resin foam. Since it is possible to use a loss of burr or the like, a defective molded product, or a recycled material of used foam, there is an advantage in price.

  By the way, in the seat back 50 which is a different hardness pad in the prior art, as shown in FIG. 5, a non-woven reinforcing material 53 is on the back surface portion 54 of the bag-shaped portion 52 surrounded by the flange portion 51 on three sides. A block 55 in which a resin foam chip is bonded is embedded in a back surface portion 54 that is integrally formed so as to form a layer and is separated from the reinforcing material 53. The surface of the block 55 and the surface of the back surface part 54 are the same height. In addition, the lower left side of FIG. 5 is the lower part 57, the upper right side is the top part 56, and a headrest (not shown) is arranged on the top part 56.

  Around the block 55 embedded in the polyurethane foam in this way, there is a problem that a recess having a size that causes an appearance defect is easily formed due to gas accumulation, and the position where the recess is formed is not constant. is there. The mechanism of the concave portion generation will be briefly described with reference to FIG.

  As shown in FIG. 6A, below the block 55 supported by the cavity surface 61 of the middle mold 60, a foam 62 in which a polyurethane raw material injected into a lower mold (not shown) is expanded. Then, the foam 62 further expands to increase its height, and as shown in FIG. 6 (b), a part of the foam 62 comes into contact with the lower surface of the block 55, and a gas reservoir 63 having nowhere to go is generated. To do. The component of the gas reservoir 63 is composed of a gas generated when the air present in the foaming mold and the polyurethane raw material chemically react. Then, the mixed gas in the gas reservoir 63 is pressed by the foam 62 and enters the block 55. However, there is already air in the block 55 between the chips of the resin foam, and the air expands due to the heat of the foaming mold whose temperature is adjusted and the chemical reaction heat of the polyurethane raw material. Then, in the block 55, the mixed gas to enter and the expanding air cannot be accommodated, and the block 55 discharges the gas to the periphery.

  Further, as shown in FIG. 6C, when the foam 62 expands and covers the periphery of the block 55, the expansion of the foam 62 is prevented by the mixed gas that has lost the escape space, and the recess 64 is formed. Is done. The position where the concave portion 64 is generated is not fixed, and it is difficult to prevent the concave portion 64 from being generated depending on molding conditions.

  The present invention has been made paying attention to such problems, and the object of the present invention is a method of forming a different hardness pad using a breathable block, which increases equipment costs and material costs. It is another object of the present invention to provide a method for forming a different hardness pad in which a gas reservoir is not formed around a breathable block. Another object of the present invention is to provide a foam mold used for the molding method.

  In order to solve the above-mentioned problem, the invention of the different hardness pad molding method according to claim 1 is a polyurethane foam different hardness pad molding method in which a breathable block is embedded so that the hardness is partially different. The breathable block is disposed on a cavity surface of the middle mold or upper mold of the foam molding die, and a part of the breathable block is connected to a breathable sheet disposed on the cavity surface, so that the inside of the breathable block is The breathable sheet is connected to a state allowing gas movement, and is a side surface of the breathable block, and is a remote side surface farthest from a connecting portion between the breathable block and the breathable sheet. A shield plate is brought into contact with the base plate.

  In the first aspect of the present invention, a breathable block is disposed on a cavity surface of a middle mold or an upper mold of a foam mold for molding a different hardness pad made of polyurethane foam, and a part of the breathable block is disposed in the cavity. The inside of the air permeable block and the air permeable sheet were connected to each other in a state in which gas movement was allowed, connected to the air permeable sheet disposed on the surface. And the remote side surface which is a side surface of the air permeable block and is farthest from the side surface to which the air permeable sheet is connected is in contact with the shield plate. Therefore, when the polyurethane raw material expands and comes into contact with the breathable block, even if a mixed gas of the air in the foaming mold and the gas generated by the chemical reaction of the polyurethane raw material enters the breathable block, the mixed gas Since the path is blocked by the shield plate, it can move to the side where the breathable sheet is connected, and can diffuse into the breathable sheet. Therefore, the mixed gas released around the breathable block and the mixed gas confined in the lower part of the side surface of the breathable block by the foam form a recess due to a gas reservoir in an indefinite position, which may cause poor appearance. Is prevented.

  According to a second aspect of the present invention, in the method for forming a different hardness pad according to the first aspect, the air permeable block has a rectangular parallelepiped shape in which a resin foam chip is bound by a binder, and one side surface thereof. The remote side surface facing the one side surface is in contact with the shield plate.

  According to the second aspect of the present invention, the air permeable block is a plate-shaped rectangular parallelepiped in which a resin foam chip is bound by a binder. This resin foam chip can be used for loss of burrs, etc. formed during molding of the resin foam, defective molded products or recycled material of used resin foam, and the chip can be used with a binder. Since the air-permeable block is simply joined, an increase in material cost can be prevented.

  According to a third aspect of the present invention, in the method for forming a different hardness pad according to the first or second aspect, the breathable sheet is a non-woven fabric, a woven fabric or a net-like material disposed in the middle mold or upper mold of the foam mold. It is a sheet formed of any one of the bodies.

  According to the third aspect of the present invention, since the breathable sheet is formed of any one of a nonwoven fabric, a woven fabric, or a net-like body, the back surface of the different hardness pad is used as a reinforcing material or the back surface of the pad is a frame. It can be appropriately selected and used as an anti-noise material for preventing abnormal noise generated by contacting the

  According to a fourth aspect of the present invention, in the method for forming a different hardness pad according to the first or second aspect, the breathable sheet includes a breathable reinforcing material that reinforces the back surface of the different hardness pad, and the reinforcing material. It comprises a strip-like breathable connecting material that is connected in a breathable manner and is connected to the breathable block in a breathable manner.

  According to the invention described in claim 4, the breathable reinforcing material and the breathable block are connected to each other so as to be ventilated by the strip-shaped breathable connecting material. Therefore, the size of the reinforcing material does not need to be a size that can be directly connected to the air-permeable block, and can be set to a minimum size required for reinforcement. The connecting material may be any material as long as it can maintain air permeability even when in contact with the polyurethane raw material, and does not need to have a function as a reinforcing material. It is possible to select and use a low-cost material as compared with the above.

  According to a fifth aspect of the present invention, in the method for forming a different hardness pad according to any one of the first to fourth aspects, the end of the breathable sheet disposed on the cavity surface is the breathable block. And the cavity surface of the middle mold or the upper mold.

According to the fifth aspect of the present invention, since the end of the breathable sheet is sandwiched between the breathable block and the cavity surface, there is no need to provide a pin or the like for fixing the end of the breathable sheet.
The foam molding die according to claim 6 is a foam molding die for molding a different hardness pad made of polyurethane foam, and a breathable sheet is supported on a cavity surface of the middle mold or upper mold of the foam mold. A support part is provided, and a sandwiching part for sandwiching the breathable block on its left and right side surfaces is provided, and is a side surface of the breathable block sandwiched by the sandwiching part, and faces the breathable sheet. A shield plate is provided at a position where it can come into contact with a remote side surface located farthest from the side surface.

  According to the sixth aspect of the present invention, the breathable sheet can be supported by the support portion on the cavity surface of the middle mold or the upper mold of the foam mold for molding the different hardness pad made of polyurethane foam. Can be clamped by the clamping part. In the cavity surface, a shield plate is provided at a position that can be brought into contact with the side surface of the breathable block that is sandwiched by the sandwiching portion and that is farthest from the surface facing the breathable sheet. Therefore, it is possible to provide a foam molding die for molding a pad of different hardness using a breathable block with such a simple structure.

  According to the present invention, a pad having a different hardness is formed using a breathable block, which prevents an increase in equipment costs and material costs, and prevents formation of a gas reservoir around the breathable block. It is possible to provide a method for forming a different hardness pad with good appearance. Moreover, the foaming mold used for the molding method can be provided.

(Embodiment)
Hereinafter, embodiments embodying the present invention will be described with reference to FIGS. In addition, about the same structure as a prior art, the same code | symbol used in the description shall be used.

  First, the configuration of the foam molding die 70 of the present embodiment is a conventionally known configuration. As shown in FIG. 7, the lower die 72, the upper die 71 that is closed with respect to the lower die 72, and the The middle mold 60 is supported by the upper mold 71 and disposed between the lower mold 72 and the upper mold 71. The middle mold 60 supported by the upper mold 71 is supported so as to be separated from the upper mold 71 in order to release the molded foam after the upper mold 71 is opened. However, since the mechanism is publicly known, illustration and description are omitted.

  Hereinafter, as shown in FIG. 1, an aluminum alloy middle mold 60 for molding a seat back 30 which is a different hardness pad made of polyurethane foam will be described with a focus on the portion relating to the molding method of the present invention. 1 is a lower end portion 60b corresponding to the lower portion 57 of the seat back 30, and an upper side is an upper end portion 60a corresponding to the top portion 56.

  The cavity surface 61 of the middle mold 60 is provided with a plurality of steel support pins 14 (six in the present embodiment) as support portions for supporting a non-woven reinforcing material 53 (breathable sheet) having air permeability. ing. In addition, the cavity surface 61 has a plurality of steel-made pin 12 (in this embodiment) as a pinch portion for pinching the block 55, which is a breathable block, on the left and right side surfaces (left and right in FIG. 1A). 2 on each side). The cavity surface 61 is provided with a shield plate 11 made of an aluminum plate in a direction perpendicular to the direction in which the two left and right holding pins 12 are arranged and perpendicular to the cavity surface 61.

Next, a method for forming the seat back 30 which is a pad of different hardness using the foaming mold will be described.
First, the reinforcing material 53 is pressed against the six support pins 14 in the cavity surface 61 of the middle die 60 that is opened with the upper die and is directed toward the worker side, and the support pins 14 are stuck in the reinforcing material 53. The reinforcing material 53 is arranged so as to be supported. At this time, since one end of the strip-like connecting material 13 (breathable sheet) also made of the nonwoven fabric is stitched as a connecting portion to the felt-like nonwoven fabric reinforcing material 53 of the present embodiment, it faces the one end. The other end of the connecting member 13 on the side is in a suspended state. In the present embodiment, the reinforcing material 53 and the connecting material 13 are formed using a non-woven sheet, but a woven cloth or a net-like body can be used instead of the non-woven cloth.

  Next, a rectangular parallelepiped block 55 in which a polyurethane foam chip is bonded as a resin foam by a binder is pressed between the sandwiching pins 12 so that the block 55 is sandwiched between the two sandwiching pins 12 on the left and right sides. Try to be pinched. At this time, the block 55 is arranged so that the side surface 55 b which is the remote side surface farthest from the side surface 55 a facing the connecting material 13 of the block 55 comes into contact with the side surface of the shield plate 11. Then, at the time of the arrangement, on the side surface 55 a side of the block 55, the other end of the connecting material 13 is sandwiched between the block 55 and the cavity surface 61 of the middle mold 60, so that the block 55 and the connecting material 13 are arranged. And connecting.

  In this manner, when the setting of the reinforcing material 53 and the connecting material 13 with respect to the cavity surface 61 of the middle mold 60 and the block 55 is completed, the polyurethane raw material is injected into the lower mold (not shown) and then the upper mold (not shown) together with the middle mold 60. ) Is closed, and the seat back 30 which is a different hardness pad made of polyurethane foam is molded. In this molding method, a state in which the recess 64 due to the gas reservoir is not formed around the block 55 will be described with reference to the foam 62 and the gas behavior shown in FIG. The description of the same parts as those described with reference to FIG. 6 is simplified or omitted.

  The state shown in FIG. 2A is different from the state shown in FIG. 6A in that the side surface 55b of the block 55 is in contact with the shield plate 11, and the block 55 on the side surface 55a side and the cavity surface 61 of the middle die 60. The other parts are the same except that the connecting member 13 is sandwiched between them.

  The expanded state of the foam 62 shown in FIG. 2B is almost the same as the state shown in FIG. 6B, but the path of the gas toward the side surface 55b is blocked by the shield plate 11. And is not discharged to the outside of the block 55 through the side surface 55b. Therefore, the expanded air in the block 55 and the mixed gas that has entered the block 55 diffuse to the reinforcing material 53 side through the connecting material 13. At this time, if a gap is formed in the fitting hole of the support pin 14 with respect to the middle mold 60 as described above, the gas is easily discharged out of the mold from the gap.

As shown in FIG. 2C, the recess 64 is not formed around the block 55, and the block 55 is embedded in the foam 62 without a gap.
As shown in FIGS. 3 and 4, the seat back 30 molded by the molding method of the present embodiment has the connecting material 13 that connects the reinforcing material 53 and the block 55, and the front surface and the back surface portion 54 have the same height. The seat back 50 is embedded in the foam 62 as the surface and the connecting material 13 is not embedded, only the presence or absence of the connecting material 13 is different, and the other parts are the same. Of course, the recess 64 having a size corresponding to the appearance defect seen in the seat back 50 is not formed in the seat back 30. A hole denoted by reference numeral 58 in FIG. 4 is an insertion hole 58 for inserting a cylindrical support body that supports the headrest stay.

  As shown in FIG. 4, the slit portion 40 is drawn between the side surface 55 b of the block 55 and the foam body 62, but the slit portion 40 is normally closed by pressure from the surroundings on the foam body 62. It is a narrow gap, and cannot be a recess corresponding to an appearance defect.

Therefore, according to the above embodiment, the following effects can be obtained.
(1) In the said embodiment, the block 55, the reinforcing material 53, and the connection material 13 were arrange | positioned in the cavity surface 61 of the intermediate mold 60 of the foam molding die which shape | molds the different hardness pad made from a polyurethane foam. And the inside of the block 55 and the reinforcing material 53 were connected to the state in which the movement of gas is permitted via the connecting material 13. On the other hand, the shield plate 11 is in contact with the side surface 55b which is the remote side surface farthest from the side surface 55a facing the connecting member 13 of the block 55. Therefore, even if the mixed gas of the air in the foaming mold and the gas generated by the chemical reaction of the polyurethane raw material enters the block 55, the gas is blocked by the shield plate, so the side of the connecting material 13 And can diffuse in the reinforcing material 53. Therefore, formation of a recess due to a gas reservoir at an indefinite position around the block 55 is prevented, and a pad with a different hardness can be formed with a good appearance. Furthermore, since the polyurethane raw material is impregnated on the side surface of the block 55 where the shield plate 11 is not in contact, the block 55 and the foam 62 can be firmly bonded.

  (2) In the above embodiment, the block 55 has a rectangular parallelepiped shape in which a polyurethane foam chip is bound by a binder. The polyurethane foam chip can use a loss such as a burr formed at the time of molding the polyurethane foam, a defective molded product, or a recycled material of used polyurethane foam. Therefore, since the block 55 in which the chip is simply bonded with the binder is used, it is possible to provide a method for forming a different hardness pad in which an increase in material cost is prevented.

  (3) In the above embodiment, the reinforcing material 53 and the connecting material 13 are formed of any one of a nonwoven fabric, a woven fabric, or a net-like body. Therefore, the material can be appropriately selected as a reinforcing material in the back surface portion 54 of the seat back 30 or as a noise preventing material that prevents noise generated by the back surface portion 54 coming into contact with the frame.

  (4) In the above embodiment, the breathable reinforcing member 53 and the breathable block 55 are connected to each other by the strip-shaped breathable connecting member 13 so as to allow ventilation. Therefore, in order to allow gas to flow, the size of the reinforcing member 53 does not need to be a size that can be directly connected to the block 55, and can be a minimum necessary size for reinforcement. Therefore, the material cost concerning a nonwoven fabric can be reduced.

  (5) In the above embodiment, the breathable reinforcing material 53 can be supported by the support pins 14 on the cavity surface 61 of the middle mold 60 of the foam molding die for molding the different hardness pad made of polyurethane foam. The block 55 can be clamped by the clamp pin 12. In the cavity surface 61, the shield plate 11 is provided at a position where it can come into contact with the side surface 55b, which is the remote side surface farthest from the side surface 55a facing the connecting member 13 in the sandwiched block 55. Therefore, it is possible to provide a foam molding die for molding the different hardness pad with such a simple structure.

  (6) In the above embodiment, the end portion of the connecting material 13 can be held between the block 55 and the cavity surface 61 of the middle mold 60. Therefore, there is no need to provide a pin or the like for fixing the end portion of the connecting material 13, and the structure of the middle mold 60 can be simplified. Furthermore, since the connecting material 13 that is a breathable sheet is provided on the upper surface of the block 55, the air and gas in the block 55 can be transmitted to the connecting material 13.

(Example of change)
In addition, the said embodiment can also be changed and actualized as follows.
The seat back 30 is described as a different hardness pad, and the reinforcing material 53 is disposed on the back surface portion 54 of the bag-like portion 52 of the seat back 30, and the block 55 is disposed on the back surface portion 54 spaced from the reinforcing material 53, The form which connected between the block 55 and the reinforcing material 53 so that ventilation | gas_flowing with the connection material 13 was demonstrated. However, the arrangement of the block 55 and the reinforcing material 53 is possible at an arbitrary position, and can be arranged according to the respective needs. For example, after the blocks 55 are arranged at the left and right ends of the back surface portion 54 and the connecting material 13 is arranged in the two blocks 55, the connecting material 13 ventilates between the blocks 55 and the reinforcing material 53. You may make it connect as possible. In addition, according to such arrangement | positioning of the block 55, it becomes possible to support a seated person's waist | hip | lumbar part by a different hardness part with high hardness.
-Although the shaping | molding method of the seat back 30 of a different hardness pad was demonstrated, this shaping | molding method should be applied to the seat cushion which is not shown in figure. At that time, since the foaming mold used is generally composed of a lower mold and an upper mold, the block 55, the reinforcing material 53, the connecting material 13 and the like are set on the cavity surface of the upper mold. The arrangement of the block 55 and the reinforcing member 53 is the same as in the case of the seat back 30, for example, the seating portion except the front side where the thigh hits or the side portions on both sides of the seating portion are made harder pads than other portions. Is optional.
The reinforcing material 53 and the connecting material 13 are formed from a non-woven fabric sheet. However, the reinforcing material 53 and the connecting material 13 are formed of different materials, for example, the non-woven material reinforcing material 53 is formed of the connecting material 13 by cold-cooling. To do. By doing so, any material can be used as long as the material of the connecting material 13 can maintain air permeability even in contact with the polyurethane raw material, and there is no need to have a function as a reinforcing material. Therefore, a low-priced material can be selected and used as compared with the nonwoven fabric.
-The nonwoven fabric reinforcing material 53 and the nonwoven fabric connecting material 13 are stitched to form a breathable sheet. However, one sheet of nonwoven fabric is cut out to form a breathable sheet.
An aluminum plate-like body was used as the shield plate 11, but another metal plate-like body such as stainless steel, or a synthetic resin plate-like body that has heat resistance higher than the reaction heat of the polyurethane raw material and does not soften, For example, use a synthetic resin plate-like body having poor adhesion to polyurethane raw materials such as polyethylene, polypropylene or polyamide.
・ A polyurethane foam chip assembly was used as the resin foam, but a known foam chip made of thermoplastic resin such as polyethylene, polypropylene, polystyrene, or the polyurethane foam chip and thermoplastic was used. Use a mixture of resin foam chips.
-Although the shape of the block 55 is a plate-shaped rectangular parallelepiped, it should be a hexahedron other than a rectangular parallelepiped, or a deformed block having a surface that abuts against the cavity surface 61 of the middle die 60.
The block 55 is sandwiched between the sandwiching pins 12, but the block 55 is pressed against the sandwiching pin 12 so that the block 55 is supported while the sandwiching pin 12 is stuck in the block 55.

BRIEF DESCRIPTION OF THE DRAWINGS The reinforcement material, connecting material, and block which were set to the intermediate | middle type | mold of embodiment of this invention and a middle type | mold are shown typically, (a) is a front view, (b) is a side view. Sectional drawing which demonstrates typically the effect | action in embodiment of the shaping | molding method of this invention in order of (a)-(c) using the AA arrow line view of Fig.1 (a). The perspective view which shows the seat back obtained by the shaping | molding method of this invention. Sectional drawing of the BB arrow in FIG. The perspective view which shows the seat back in a prior art. Sectional drawing which demonstrates typically the effect | action at the time of shape | molding the seat back of a prior art in order of (a)-(c). Sectional drawing which shows a foaming mold typically.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Shield plate, 13 ... Connection material, 53 ... Reinforcement material, 55a, 55b ... Side surface, 60 ... Medium type, 61 ... Cavity surface, 70 ... Foam molding die, 71 ... Upper die, 72 ... Lower die

Claims (6)

  In the method of molding a different hardness pad made of polyurethane foam in which a breathable block is embedded so that the hardness is partially different, the breathable block is disposed on a cavity surface of a middle mold or an upper mold of a foam mold, A part of the breathable sheet is connected to the breathable sheet disposed on the cavity surface, so that the breathable block and the breathable sheet are connected to each other in a state that allows gas movement, and the breathable block is connected. A method of forming a pad with different hardness, wherein a shield plate is brought into contact with a remote side surface that is the farthest side from the connecting portion between the breathable block and the breathable sheet.   The air-permeable block has a rectangular parallelepiped shape in which a resin foam chip is bonded by a binder, and is connected to the air-permeable sheet on one side surface, and the remote side surface facing the one side surface is the shield. The method for forming a different hardness pad according to claim 1, wherein the pad is brought into contact with a plate.   The air-permeable sheet is a sheet formed of any one of a nonwoven fabric, a woven fabric, or a net-like body disposed in the middle mold or the upper mold of the foam molding die. The forming method of the different hardness pad of description.   The breathable sheet includes a breathable reinforcing material that reinforces the back surface of the pad of different hardness, and a strip-shaped breathable connection that is connected to the reinforcing material so as to allow ventilation, and is connected to the breathable block so as to allow ventilation. The method for forming a different hardness pad according to claim 1, wherein the pad is made of a material.   The end of the breathable sheet disposed on the cavity surface is sandwiched between the breathable block and the middle or upper cavity surface. The method for forming the different hardness pad according to item.   In a foam molding die for molding a different hardness pad made of polyurethane foam, a support portion for supporting a breathable sheet is provided on the cavity surface of the middle mold or the upper mold of the foam mold, and the breathable block is attached to the cavity mold surface. A sandwiching portion is provided to be sandwiched between the left and right side surfaces, and can be brought into contact with the side surface of the breathable block sandwiched by the sandwiching portion and farthest from the side surface facing the breathable sheet. A foaming mold characterized in that a shield plate is provided at an appropriate position.

Images