JP2018089092A - Mold of seat pad - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold of a seat pad which has a cavity for molding a seat pad between a lower mold and an upper mold and hardly generates a defect in urethane foam molding even when a protruding standing wall is formed in an in-plane direction, when viewed from an upper surface, on a cavity surface of the lower mold.SOLUTION: A mold 10 includes: a lower mold 11; an upper mold 12 for forming a cavity 13 between the lower mold 11 and the upper mold; a front standing wall part 11b which is formed on a lower molding surface 11a of the lower mold 11, extends in a protruding shape in a perpendicular direction to a seat width direction from both end parts of the seat width direction when viewed from an upper surface, and protrudes above the lower molding surface 11a; an injection surface part 11a1 which is formed inside the protruding shape of the front standing wall part 11b for receiving a soft polyurethane foam resin raw material 20; and a plurality of weirs which are formed outside the protruding shape of the front standing wall part 11b, protrude upward at a height lower than the front standing wall part 11b in parallel to the front standing wall part 11b, and are placed at a prescribed interval.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a seat pad mold for a vehicle seat mounted on a vehicle such as an automobile, an airplane, a ship, and a train.

  2. Description of the Related Art There is known a molding die for a seat pad, which is a cushion for a vehicle seat, having a cavity formed in a predetermined shape and foam-molding by injecting a flexible polyurethane foam raw material into the cavity. As shown in FIG. 6, in the seat pad molding die 50 disclosed in Patent Document 1 below, the molding surface of the lower mold 51 formed in the shape of the seating surface side of the seat pad and the back surface side of the seat pad A cavity 53 is formed between the molding surface of the upper mold 52 formed in the shape of And in the substantially central part of the molding surface of the lower mold 51, two linear standing walls 54 extending in the seat width direction are formed in parallel to form a groove shape on the seating surface of the seat pad. . In the foam molding, with the upper mold 52 opened relative to the lower mold 51, the soft polyurethane foam raw material 55 is injected into the molding surface of the lower mold 51, and then the upper mold 52 is closed and heated for a predetermined time to be foamed and solidified. Get a seat pad.

Japanese Patent Application Laid-Open No. 2015-147312

  In the seat pad mold 50 described above, the standing wall 54 for forming a groove shape on the seating surface of the seat pad is formed to extend linearly in the seat width direction. For example, when a soft polyurethane foam raw material 55 is injected on one side across the standing wall 54, the raw material expanded by foaming flows over the standing wall 54 to the other side and solidifies while foaming and solidifying while filling the cavity 53 on the other side. It reaches the other side of the standing wall 54 almost simultaneously and exerts a pressing force. As a result, the soft polyurethane foam raw material 55 on the other side of the standing wall 54 is foamed and solidified almost simultaneously, so that defects such as voids are less likely to occur. On the other hand, when the groove formed on the seating surface of the seat pad is viewed from a direction perpendicular to the seating surface, it may be convex in the in-plane direction. At this time, the standing wall is also formed in a convex shape. In such a case, when the soft polyurethane foam raw material 55 is injected inside the convex shape on one side across the standing wall, the raw material expanded by foaming flows over the standing wall to the other side and fills the cavity 53 on the other side. However, when solidifying by foaming, the time to reach the other side of the standing wall and exert a pressing force is shifted by the portion of the standing wall. That is, the raw material arrives near the top of the convex shape in a state where foam solidification has not progressed, whereas the raw material arrives at the bottom of the convex shape in a state where foam solidification has progressed. As a result, the fluidity of the foaming raw material is lowered at the convex hem portion, and it is difficult to adhere to the standing wall, and defects such as voids are likely to occur.

  In view of such problems, an object of the present invention is to provide a cavity for molding a seat pad between a lower mold and an upper mold, and to form a standing wall having a convex shape in the in-plane direction on the cavity surface of the lower mold as viewed from above. The object of the present invention is to provide a seat pad mold that is less prone to defects during urethane foam molding.

  A first invention of the present invention is a mold for a foam-molded seat pad, wherein a lower mold, an upper mold for forming a cavity for molding the seat pad between the lower mold, and the lower mold It is formed in a portion of the molding surface that forms the cavity corresponding to the seating surface of the seat pad, and extends from both ends in the seat width direction in a convex shape in a direction perpendicular to the seat width direction when viewed from above and toward the upper side of the molding surface. A standing wall portion that protrudes and an injection surface portion that is formed on the molding surface inside the convex shape of the standing wall portion and receives at least part of the foamed resin raw material that is injected into the cavity during foam molding, It is formed on the molding surface outside the convex shape, and protrudes upward at a height lower than the standing wall portion substantially parallel to the standing wall portion along the standing wall portion, and is disposed at a predetermined interval. Duplicate Characterized in that it comprises a weir, a.

  According to the first invention, when the foamed resin raw material is injected into the cavity in the foam molding of the seat pad, at least part of the foamed resin foams over the standing wall portion from the injection surface portion side of the standing wall portion and the plurality of weirs. It flows out in between. At this time, the foamed resin raw material is temporarily stored between the convex outside of the standing wall portion and the plurality of weirs, and then the convex wall outside of the standing wall portion from the upper portion of the plurality of weirs or a portion without a weir at a predetermined interval. It overflows on the molding surface and foams. When the foamed resin raw material is filled into the cavity, the foamed resin raw material is stored between the convex outside of the standing wall and the plurality of weirs, so there is a gap in the convex outer part of the standing wall. Occurrence of defects such as voids can be suppressed. Here, the outside of the protruding shape of the standing wall means the side in the direction in which the standing wall protrudes in the in-plane direction when viewed from above, and the inside of the protruding shape of the standing wall means that the standing wall is in-plane when viewed from above. The opposite side of the direction protruding in the direction.

  According to a second aspect of the present invention, in the first aspect, the injection surface portion is formed to have a height in a vertical direction higher than the molding surface outside the convex shape of the standing wall portion.

  According to the second aspect of the invention, the foamed resin raw material injected into the injection surface portion easily gets out of the standing wall portion at a high flow rate between the plurality of weirs. Thus, in the case of such a mold, when a plurality of weirs are provided and the foamed resin raw material is temporarily stored between the convex outside of the standing wall portion and the plurality of weirs, compared to the case where the plurality of weirs are not provided. The effect of suppressing the occurrence of defects such as voids becomes significant.

  According to a third aspect of the present invention, in the first or second aspect of the invention, the protruding height of the plurality of weirs from the forming surface is 1/6 of the protruding height of the standing wall portion from the forming surface. -1/2.

  According to the third aspect of the invention, the height of the plurality of weirs is set to a level necessary to suppress the occurrence of defects such as voids, so that the foamed seat pad is molded while suppressing the occurrence of defects such as voids. It becomes easy to remove from the mold without damage.

  According to a fourth aspect of the present invention, in the third aspect, a distance between the plurality of weirs and the standing wall portion in a top view is 1/3 to 3/4 of a protruding height of the standing wall portion from the molding surface. It is the length equivalent to.

  According to the fourth aspect of the present invention, the distance between the plurality of weirs and the standing wall is set to an extent necessary to suppress the occurrence of defects such as voids, so that the sheet is foam-molded while suppressing the occurrence of defects such as voids. The pad can be easily removed from the mold without damage.

  According to a fifth aspect of the present invention, in the fourth aspect, the predetermined interval in the plurality of weirs corresponds to 1/5 to 1/2 of a length extending along the standing wall portion of the plurality of weirs. It is characterized by a length.

  According to the fifth aspect of the present invention, the intervals between the plurality of weirs are set to the extent necessary to suppress the occurrence of defects such as voids. It becomes easy to remove from the mold without damage.

It is the top view which looked at the cushion pad shape | molded using the shaping | molding die of the seat pad concerning one Embodiment of this invention from the seating surface side. It is the II-II arrow directional cross-sectional view of FIG. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 1. FIG. 3 is a cross-sectional view of a seat pad mold corresponding to FIG. 2. It is an enlarged view of the V part in FIG. It is sectional drawing of the shaping | molding die of the conventional seat pad.

  1 to 5 show an embodiment of the present invention. The molding die 10 of this embodiment is a die for molding the urethane foam cushion pad 1 disposed in the seat cushion of the front seat of the automobile shown in FIG. In each figure, each direction of the automobile and the front seat when the cushion pad 1 is incorporated in the front seat and attached to the automobile is shown by arrows. In the following description, the description regarding the direction is made based on this direction. Here, the cushion pad 1 corresponds to a “seat pad” in the claims.

  As shown in FIGS. 1 to 3, the cushion pad 1 is a cushion body made of a soft polyurethane resin that exhibits a moderate cushion feeling formed in a pad shape having a predetermined thickness, and is bent by receiving a load from a seated person. However, the reaction force is exerted by elasticity to support the seated person. The cushion pad 1 includes a main portion 2 that occupies the center in the seat width direction, and a side support portion 3 that occupies both the left and right portions of the main portion 2. A longitudinal groove portion 4 extending in the front-rear direction is formed between the main portion 2 and the left and right side support portions 3. The main portion 2 includes a front horizontal groove portion 5 extending in a convex shape toward the front by connecting the vicinity of the center portion in the front-rear direction of the left and right vertical groove portions 4 and a rear portion in the front-rear direction of the left and right vertical groove portions 4. A rear lateral groove portion 6 that is connected and extends linearly in the left-right direction is formed. Specifically, the left and right vertical groove portions 4 extend substantially parallel to each other along the front-rear direction behind the front connection portion 7, which is a connection portion with the front horizontal groove portion 5. Further, the left and right vertical groove portions 4 extend so as to be gradually separated from each other toward the front in front of the front connecting portion 7. The front horizontal groove portion 5 is formed in a smooth curved shape that connects the left and right front connecting portions 7 and passes through a top portion 5a that is the most projecting position forward in the central portion in the left-right direction. The distance in the front-rear direction from the front end of the cushion pad 1 to the top portion 5 a is about half of the distance in the front-rear direction from the front end of the cushion pad 1 to the front connecting portion 7. The distance in the front-rear direction from the rear end of the cushion pad 1 to the rear lateral groove 6 is set substantially equal to the distance in the front-rear direction from the front end of the cushion pad 1 to the top 5a. The left and right vertical groove portions 4, the front horizontal groove portion 5 and the rear horizontal groove portion 6 are secured by pulling portions of a cushion cover (not shown) as a skin material to be put on the cushion pad 1 into the cushion pad 1. It functions as a groove for this purpose. Wires (not shown) for fastening the cushion cover are inserted into the bottoms of the left and right vertical groove portions 4, the front horizontal groove portion 5 and the rear horizontal groove portion 6.

  As shown in FIGS. 1 to 3, a portion of the main portion 2 in front of the front lateral groove portion 5 is formed so as to gradually protrude upward toward the front, and the thigh of the seated occupant This is the part that mainly supports the vicinity of the tip. Moreover, the part behind the front horizontal groove part 5 of the main part 2 is formed substantially horizontally, and is a part which mainly supports the buttocks from the thigh root of the seated occupant. The left and right side support parts 3 are each formed in a shape that rises in a mountain shape upward from the left and right vertical groove parts 4 toward the both outer sides, and supports the butt and thigh sides of the seated occupant from the outside. Part.

  As shown in FIG. 2, the front horizontal groove portion 5 and the rear horizontal groove portion 6 are formed in a substantially U shape whose cross section is open upward, and the depth from the seating surface side surface of the main portion 2 is The width is about 20 to 30 mm, and the width is about 10 mm. As shown in FIG. 3, the longitudinal groove portion 4 is formed in a substantially U shape whose cross section is open upward, and the depth from the seating surface side surface of the main portion 2 is about 20 to 30 mm, Its width is about 10 mm. That is, the cross sections of the front horizontal groove portion 5, the rear horizontal groove portion 6, and the vertical groove portion 4 are formed in substantially the same shape.

  As shown in FIGS. 1 and 2, seven shallow grooves 8 are formed symmetrically on the front side corresponding to the convex outer side in a top view of the front lateral groove portion 5. Each of the seven shallow grooves 8 has the same cross section, and is substantially U-shaped opening upward, and the depth from the seating surface side surface of the main portion 2 is about 5 to 10 mm. Its width is about 3-5 mm. Further, the seven shallow grooves 8 are arranged substantially parallel to the front horizontal groove portion 5 along a line separated from the center line of the front horizontal groove portion 5 by about 10 to 15 mm in the top view. The seven shallow grooves 8 have a length of about 30 to 50 mm in a top view, and an interval between adjacent shallow grooves 8 is about 10 to 15 mm. The seven shallow grooves 8 are formed by a weir 11d provided in the mold 10 in order to suppress the occurrence of defects such as voids in the vicinity of the front surface portion of the front lateral groove portion 5 when foaming the cushion pad 1 as will be described later. However, the cushion pad 1 does not have a function as a product. That is, as the product of the cushion pad 1, the seven shallow grooves 8 are preferably as small as possible.

  As shown in FIGS. 2 and 3, the surface opposite to the seating surface of the cushion pad 1 is integrally formed with a breathable thick nonwoven fabric (not shown) and adapted to the shape of the cushion frame forming the skeleton. It is shaped so that it is mounted.

  A molding die 10 for molding the cushion pad 1 described above will be described with reference to FIGS. 1, 4, and 5. The molding die 10 includes a lower die 11 having a lower molding surface 11a for molding an upper surface portion which is a seating surface portion of the cushion pad 1, and an upper die having an upper molding surface 12a for molding a lower surface portion which is a back surface portion of the cushion pad 1. 12 and. A cavity portion surrounded by the lower molding surface 11a of the lower mold 11 and the upper molding surface 12a of the upper mold 12 is a cavity 13, and the shape of the cavity 13 corresponds to the shape of the cushion pad 1. As shown in FIG. 4, a front standing wall portion 11 b, a rear standing wall portion 11 c, and a weir 11 d are erected on the lower molding surface 11 a of the lower mold 11. The front standing wall portion 11b, the rear standing wall portion 11c, and the weir 11d are disposed in shapes and positions corresponding to the front lateral groove portion 5, the rear lateral groove portion 6 and the shallow groove 8 of the cushion pad 1, respectively. That is, the front wall portion 11b is formed so as to be curved and extend in a convex shape toward the front in a top view, and the left and right side connection portions corresponding to the left and right front connection portions 7 and the top portion 5a of the cushion pad 1. (Not shown) and a top portion 11b1. The weir 11d is disposed substantially parallel to the standing wall portion 11b along a line separated from the center line of the standing wall portion 11b by about 10 to 15 mm in front view. Although not shown in FIG. 4, left and right side wall portions corresponding to the left and right vertical groove portions 4 of the cushion pad 1 are also provided. Here, the standing wall portion 11b corresponds to a “standing wall portion” in the claims. Further, the lower molding surface 11a and the upper molding surface 12a correspond to the “molding surface” in the claims.

  As shown in FIG. 5, the standing wall 11b has a height H1 of about 20 to 30 mm and a width W1 of about 10 mm in its transverse cross section. Further, the weir 11d has a height H2 of about 5 to 10 mm and a width W2 of about 3 to 5 mm in the transverse section. And the distance D of the centerline in the cross section of the standing wall part 11b and the centerline in the cross section of the weir 11d is about 10-15 mm. Seven weirs 11d are provided corresponding to the shallow grooves 8 in FIG. 1, each having a length of about 30 to 50 mm, and the gap G (see FIG. 1) between the adjacent weirs 11d and weirs 11d is It is about 10-15 mm. The lower molding surface 11a is formed so as to incline upward (in the direction of the lower mold) toward the front in a portion in front of the rear standing wall 11c in a substantially horizontal state at a portion rearward from the rear standing wall 11c. ing. Here, the height H1, the height H2, the distance D, and the gap G are respectively “protrusion height from the molding surface of the standing wall portion”, “projection height from the molding surface of the weir” in the claims, This corresponds to “the interval between the weir and the standing wall” and “the predetermined interval”.

  The lower molding surface 11a between the front wall portion 11b and the rear wall portion 11c is provided with an injection surface portion 11a1 on which the soft polyurethane foam raw material 20 is placed when the soft polyurethane foam raw material 20 is injected into the cavity 13. ing. When the soft polyurethane foam raw material 20 is injected into the cavity 13, all remains in the injection surface portion 11a1 in a state before foaming. However, a part of the soft polyurethane foam raw material 20 may be injected forward from the front wall portion 11b and remain in the state before foaming. The lower molding surface 11a is formed so as to incline upward (in the direction of the lower mold) toward the front in the portion in front of the rear wall portion 11c, so that the injected flexible polyurethane foam raw material 20 is foamed. However, it flows over the front wall 11b. Here, the flexible polyurethane foam raw material 20 corresponds to the “foamed resin raw material” in the claims.

  The upper mold surface 12a of the upper mold 12 is provided with a locking mechanism (not shown) for temporarily fixing a thick nonwoven fabric. Further, a sealing member (not shown) is disposed on the parting surface portions of the lower mold 11 and the upper mold 12 as necessary. Moreover, the lower mold | type 11 and the upper mold | type 12 are temperature-controlled to predetermined temperature as needed.

  A method for manufacturing the cushion pad 1 using the mold 10 described above will be described. As shown in FIG. 4, in a state where the upper mold 12 is opened with respect to the lower mold 11, a predetermined amount of the flexible polyurethane foam raw material 20 is injected into the injection surface portion 11 a 1 of the lower mold 11 to close the upper mold 12. As a result, the soft polyurethane foam raw material 20 expands and fills the cavity 13 while expanding. At this time, the soft polyurethane foam raw material 20 that flows forward through the standing wall portion 11b moves over the weir 11d while being stored in the region between the standing wall portion 11b and the weir 11d, or the weir 11d. It flows forward from the gap with the weir 11d. And when it reaches the uppermost part of the lower molding surface 11a (the most depressed part in the lower mold direction), the foaming is carried out upward from there to advance the expansion. Due to the expansion accompanying the foaming, the soft polyurethane foam raw material 20 reaches the upper molding surface 12a of the upper mold 12 and fills the cavity 13 from the front to the rear. Then, the mold-clamping state is maintained for a predetermined time while the inside of the cavity 13 is filled with the soft polyurethane foam raw material 20, whereby the soft polyurethane foam raw material 20 is solidified in the foamed state to form the cushion pad 1. Here, a part of the injected soft polyurethane foam raw material 20 is foamed and solidified in a state where it is stored in a region between the standing wall portion 11b and the weir 11d. Thus, a void or the like is formed on the front surface side of the front wall portion 11b as compared with the case where the flexible polyurethane foam raw material 20 once flows to the uppermost portion of the lower molding surface 11a and then expands and expands rearward without the weir 11d. It is hard to generate the trouble. In particular, in the vicinity of the connecting portion between the left and right side standing wall portions of the front wall portion 11b, the soft polyurethane foam raw material 20 arrives in a more advanced state of solidification, so that defects such as voids are likely to occur. The molded cushion pad 1 is removed from the lower mold 11 by opening the upper mold 12. At this time, since the height, width, length, and distance from the standing wall portion 11b of the weir 11d are set appropriately, the occurrence of problems such as breakage of the cushion pad 1 can be suppressed.

  As mentioned above, although specific embodiment was described, this invention is not limited to those external appearances and structures, A various change, addition, and deletion are possible in the range which does not change the summary of this invention. For example, the following can be mentioned.

  1. In the said embodiment, although the top part 5a of the front horizontal groove part 5 of the cushion pad 1 was set as the front, it is good not only as this but the structure which the top part 5a of the front horizontal groove part 5 exists in the back.

  2. In the above embodiment, the present invention is applied to the mold 10 of the cushion pad 1 of the front seat of the automobile. However, the present invention is not limited to this, and the present invention may be applied to a mold for forming a back pad for an automobile front seat, or may be applied to a mold for cushion pad or back pad for an automobile rear seat. Furthermore, the present invention may be applied to a seat mounted on an airplane, a ship, a train, or the like.

  3. In the above-described embodiment, the front lateral groove 5 has a shape that is curved and extends in a convex shape toward the front symmetrically in a top view, but is not limited to this, and the top portion 11b1 is shifted to either the left or right. It may be a shape. The same applies to the case where the shape is curved and extended in a convex shape toward the rear.

1 Cushion pad (seat pad)
10 Mold 11 Lower mold 11a Lower molding surface (Molding surface)
11a1 Injection surface part 11b Standing wall part (standing wall part)
11b1 Top 11d Weir 12 Upper mold 12a Upper molding surface (molding surface)
13 Cavity 20 Soft polyurethane foam raw material (foamed resin raw material)
H1 height (height protruding from the molding surface of the standing wall)
H2 height (height protruding from the weir molding surface)
D distance (distance between weir and standing wall)
G gap (predetermined interval)

Claims (5)

A mold for a seat pad to be foam-molded,
With the lower mold,
An upper mold for forming a cavity for molding the seat pad between the lower mold and the lower mold;
The molding surface of the lower mold is formed in a portion corresponding to the seating surface of the seat pad and extends in a convex shape from both ends in the seat width direction in a direction perpendicular to the seat width direction when viewed from above. A standing wall portion projecting upward from
An injection surface portion for receiving at least a part of a foamed resin raw material formed on the molding surface inside the convex shape of the standing wall portion and injected into the cavity at the time of foam molding;
It is formed on the molding surface outside the convex shape of the standing wall portion, protrudes upward along the standing wall portion at a height lower than the standing wall portion substantially parallel to the standing wall portion, and with a predetermined interval. A plurality of weirs disposed;
A mold for forming a seat pad.   2. The seat pad molding die according to claim 1, wherein the injection surface portion has a height in a vertical direction higher than that of the molding surface outside the convex shape of the standing wall portion.   3. The seat pad molding according to claim 1, wherein a protruding height of the plurality of weirs from the molding surface is 1/6 to 1/2 of a protruding height of the standing wall portion from the molding surface. Type.   4. The seat pad according to claim 3, wherein a distance between the plurality of weirs and the standing wall portion in a top view is a length corresponding to 1/3 to 3/4 of a protruding height of the standing wall portion from the molding surface. Mold. 5. The seat pad mold according to claim 4, wherein the predetermined interval in the plurality of weirs is a length corresponding to 1/5 to 1/2 of a length extending along the standing wall portion of the plurality of weirs. .

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