JP2006015664A - Foaming and shaping mold and manufacturing method of foaming and shaping mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of inexpensively manufacturing a foaming and shaping mold capable of exactly preventing burr from being generated while reducing man-hour. <P>SOLUTION: The manufacturing method of the foaming and shaping mold 10 having a lower mold 12 and an upper mold 16 and having a groove 26 for inserting a buffering material 28 in a mating surface 24 of the upper mold 16 of the mating surfaces 22 and 24 of the lower mold 12 and the upper mold 16 comprises arranging a curable resin layer 27 in the mating portion 25 of the upper mold 16; arranging a projecting member 29 removable and attachable to the mating surface 22 of the lower mold 12; clamping the molds in this state; and opening the molds after curing the curable resin layer 27 to form the mating surface 24 of the upper mold 16 and the groove 26 on the curable resin layer 27. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a foam molding die suitable for manufacturing a seat pad, which is a cushion used mainly for automobile seats, and a method for manufacturing the foam molding die.

  A seat pad called a cushion pad or a bag pad used for a seat portion or a backrest portion of an automobile seat is made of a foamed molded body such as a flexible polyurethane foam. In general, such a foamed molded article is obtained by injecting a foamed resin stock solution into the mold using a foamed mold having an upper mold and a lower mold, and closing the mold to foam the foamed resin stock solution in the mold. Molded by curing.

  Since the foam molding die forms a foam molding space by joining two or more dies as described above, if the sealing property of the mating surface to be a joint is insufficient, The foamed resin stock solution enters between the mating surfaces with the mold, and burrs are generated around the obtained foamed molded product.

When such burrs are generated, streaks appear on the surface through the cover material covering the pads, and therefore it is necessary to perform a deburring operation after molding. In particular, with respect to the back pad 1 used for the backrest portion of the automobile seat as shown in FIG. 6, a so-called three-divided mold is used and the flange-like overhanging portion 4 facing inward is integrally formed on the back side of the pad. Since it is formed, the parting line PL corresponding to the mating surface of the upper die and the lower die comes to a place where the upper side and both sides of the pad are easy to see, and therefore it is necessary to remove the burr reliably.

  However, in the case of a foamed molded product, the burrs are formed by minute gaps between the mating surfaces, and thus tend to have a dense foamed structure. Compared to the flexible foamed molded product body, a hard burr is called a cured core. Will be formed. Therefore, the work to remove burrs without damaging the foam body requires more man-hours than repairing the missing wall at the time of molding. Therefore, in the case of foam molded products, burrs do not occur during foam molding. Such measures are important.

  For the purpose of eliminating the deburring process as described above, an electrical discharge machining surface having a width of 5 to 30 mm is provided on the mating surfaces of the pair of molding dies, and the pair of molding dies are sealed by the electrical discharge machining surfaces. A urethane foam mold configured as described above has been proposed (for example, Patent Document 1). If the mating surface is an electric discharge machined surface, the upper die and the lower die are joined together without any gaps at the mating surface, but this alone causes gas in the mold to leak from the mating surface during foam molding, and foaming occurs along with the gas. The resin stock solution enters the mating surfaces and generates burrs.

  Therefore, the present applicant has first proposed a foam molding die in which a mating surface of the upper die and the lower die is formed by electric discharge machining, and a groove for mounting a cushioning material is provided on the mating surface of the upper die. (Japanese Patent Application No. 2003-313281). In this foam molding die, gas leakage from the mating surfaces is eliminated by pressing the cushioning material against the mating surfaces of the lower mold and sealing the mating surfaces when the molds are closed. Further, the foamed resin stock solution does not enter the mating surfaces, so that the generation of burrs can be reliably prevented.

However, in the foam molding die having the above-mentioned configuration, a groove is formed on the mating surface of the upper die by machining precision machining (NC machining) after forming a mating surface that can be closely adhered by electric discharge machining, and therefore the manufacture thereof It was a problem that took a lot of time and cost.
JP-A-9-286030

  The present invention has been made in view of the above points, and provides a foam molding die and a method for producing the same, which can reduce the number of man-hours, suppress the production period and cost, and reliably prevent the generation of burrs in the foam molded article. The purpose is to provide.

  The method for producing a foamed molded article of the present invention includes a one-type mold and the other mold, and a foam in which a groove for mounting a cushioning material is provided on the mating surface of the one mold among the mating surfaces of the one mold and the other mold. In the mold manufacturing method, a curable resin layer is disposed on the mating portion of the one mold, a detachable convex member is disposed on the mating surface of the other mold, and in this state, the mold is closed to form a curable resin layer. After curing, the mold is opened to form the mating surface of the one mold and the groove in the curable resin layer.

  Further, the foam molding die of the present invention is provided with one mold and the other mold, and foam molding in which a groove for mounting a cushioning material is provided on the mating surface of one mold among the mating surfaces of the one mold and the other mold. The mold is characterized in that a curable resin layer is disposed on the mating portion of the one mold, and the mating surface of the one mold and the groove are provided in the curable resin layer.

  In this way, the curable resin layer is disposed on the mating portion of the one mold, the convex member is disposed on the mating surface of the other mold, and the mold is closed in this state, thereby closely contacting the mating surface of the other mold to the curable resin layer. Since the possible mating surfaces and the groove for mounting the cushioning material can be stamped at the same time, electric discharge machining and mechanical precision machining become unnecessary, and therefore the manufacturing period and cost can be reduced.

  According to the present invention, since the mating surface and the groove are simultaneously molded by press-curing the curable resin layer, electric discharge machining and mechanical precision machining become unnecessary, and the manufacturing man-hour and manufacturing cost of the foam mold are suppressed. be able to.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional view of a foam molding die 10 according to the present embodiment, FIG. 2 is a cross-sectional view showing the foam molding die 10 before the curable resin layer 27 is disposed, and FIG. FIG. 4 is a cross-sectional view of the foam molding die 10 on which the cushioning material 28 is mounted, and FIG. 5 is an enlarged cross-sectional view of the main part of FIG.

  This embodiment relates to a foam molding die 10 shown in FIG. 1 for foam molding of a seat pad 1 used for a backrest portion of a front seat of an automobile made of a flexible polyurethane foam shown in FIG. 6, and a method for manufacturing the same. is there.

  As shown in FIG. 1, the foam molding die 10 includes a lower die 12 that opens upward, an upper die 16 that opens and closes an upper surface opening of the lower die, and a core die 18 provided in the upper die 16. This is a three-part mold. Specifically, the lower mold 12 is a mold for molding the surface side of the pad 1 and has a concave portion corresponding thereto. The upper mold 16 and the core mold 18 are molds for molding the back side of the pad 1, and the upper mold 16 is attached to the lower mold 12 in a state where the core mold 18 is bonded to the lower surface of the upper mold 16. By closing, a foam molding space 20 corresponding to the pad shape is formed inside the foam molding die 10.

  The lower mold 12 and the upper mold 16 are respectively provided with mating surfaces 22 and 24 that serve as joints, and the mating surface 24 of the upper mold 16 is provided with a groove 26 for mounting a cushioning material 28. The material 28 is in contact with the mating surface 22 of the lower mold 12 so that the foam molding space 20 is sealed. The mating surface 24 and the groove 26 of the upper mold 16 are provided in a curable resin layer 27 disposed in the mating portion 25.

  As shown in FIGS. 2 and 3A, the foam mold 10 is finished with the lower mold 12, the upper mold 16 and the core mold 18 cast into a predetermined shape, and then the lower mold 12. The upper die 16 and the upper die 16 are assembled so as to be rotatable via the hinge portion 14, and the core die 18 is assembled to the lower surface of the upper die 16 by the driving means 19. Specifically, the lower mold 12 includes a concave portion that matches the shape of the surface side of the pad 1 for the sheet, and a mating surface 22 that has a substantially constant width along the entire periphery of the opening along the peripheral edge of the opening of the concave portion. Molded. Further, the upper die 16 and the core die 18 are molded so as to correspond to the back surface shape of the sheet pad 1 in a state where they are joined, and the upper die 16 further includes an upper surface opening of a concave portion of the lower die 12. A matching portion 25 having a substantially constant width is disposed at a position corresponding to the mating surface 22 of the lower mold 12 when the is closed, that is, on the entire outer circumference of the bottom surface of the upper mold 16. Molded to provide.

  Next, a groove 26 for mounting the mating surface 24 of the upper mold 16 and the buffer material 28 is provided. Specifically, as shown in FIG. 3, a curable resin layer 27 having a substantially uniform thickness is disposed by applying a curable resin to the mating portion 25 of the upper mold 16, and the mating surface 22 of the lower mold 12 is disposed. A resin-made or metal-made convex member 29 extending along the entire length, that is, in the circumferential direction is disposed (see FIG. 3B). In this state, the curable resin layer 27 is not cured and is a resin layer in a gel state. Further, the convex member 29 is attached and fixed by, for example, a double-sided tape so that it can be removed later. Next, the upper die 16 is closed with respect to the lower die 12, and the shape of the mating surface 22 of the lower die 12 and the shape of the convex member 29 are embossed into the gel curable resin layer 27 (FIG. 3 (c). )reference). Then, after the curable resin layer 27 is cured by being left for a predetermined time in this state, the mold opening is performed, so that the surface of the curable resin layer 27 has a mating surface 24 that can adhere to the mating surface 22 of the lower mold 12. Grooves 26 are formed (see FIG. 3D), and the convex member 29 is removed from the mating surface 22 of the lower mold 12 to complete the foam mold 10.

  In addition, as a curable resin used for the curable resin layer 27, a well-known substance can be employ | adopted, for example, an epoxy resin, a phenol resin, a melanin resin, an unsaturated polyester resin etc. can be mentioned.

  Further, after the convex member 29 is disposed on the mating surface 22 of the lower mold 12 (see FIG. 3B), a release agent may be applied to the convex member 29 and the mating surface 22. This facilitates the mold opening process after the stamping.

  As shown in FIGS. 4 and 5, the foam molding die 10 thus formed is a string-like cushioning material made of a rubber elastic body as a sealing material into a groove 26 provided on the mating surface 24 of the upper die 16. It is used after attaching 28.

  Although the groove 26 is provided over the entire length of the mating surface 24 in the present embodiment, it is not necessarily required to be provided over the entire length. That is, although it is necessary to provide the buffer material 28 in order to reliably prevent the generation of burrs on the upper side and both sides of the pad 1, the lower side of the pad 1 is a portion that is not exposed on the sheet surface, and burrs are generated. However, the buffer material 28 is not necessarily provided for this portion.

  The cushioning material 28 is not particularly limited as long as it can be pressed against the flat mating surface 22 of the lower mold 12 when the mold is closed to ensure the sealing performance between the mating surfaces 22, 24. In consideration of the properties, a solid rubber cushioning material 28 made of silicone rubber is used. In addition, the cross-sectional shape of the cushioning material 28 is circular in consideration of mounting properties and sealing properties. Further, the cushioning material 28 is set to a size such that a part of the cushioning material 28 protrudes from the mating surface 24 by a predetermined height when fitted into the groove 26. The protrusion height h is such that the mating surfaces 22 and 24 of the lower mold 12 and the upper mold 16 can come into contact with each other while exhibiting the above-mentioned sealing performance by compressing the cushioning material 28 when the mold is closed. It is preferable to set to about 0.3-0.5 mm specifically ,. In this embodiment, the cushioning material 28 is attached over the entire circumference of the mating surface 24. In this case, when the string-like cushioning material 28 is used, a seam that connects both ends of the cushioning material 28 can be formed. The seam is preferably arranged on the lower side of the pad 1 which does not cause a problem even if burrs occur.

  Here, if an example of each dimension is given with reference to FIG. 5A, for example, when the width W of the mating surface 24 is 15 to 30 mm, the diameter of the cushioning material 28 may be about 6 to 8 mm. In the case where W = 20 mm and the diameter of the buffer material is 8 mm, the opening width w1 of the groove 26 can be 7 mm and the depth d of the groove 26 can be 6.5 mm. As described above, the groove 26 is preferably set such that both the opening width and the depth thereof are smaller than the diameter of the buffer material 28 in order to prevent the buffer material 28 from falling off.

  When the pad 1 is formed using the foaming mold 10 in which the cushioning material 28 is mounted in the groove 26 as described above, the upper mold 16 is opened with respect to the lower mold 12 as shown in FIG. As a state, the foamed urethane stock solution M is injected into the recess of the lower mold 12. Next, as shown in FIG. 4B, the upper mold 16 is closed together with the core mold 18, and the foamed urethane stock solution M is foamed and cured in the foam molding space 20. At that time, as shown in an enlarged view in FIG. 5 (b), the cushioning material 28 provided on the mating surface 24 of the upper mold 16 is pressed against the mating surface 22 of the lower mold 12 by closing the mold, so that both mating surfaces Between 22 and 24 is sealed. That is, while the cushioning material 28 of the upper mold 16 is pressed against the mating surface 22 of the lower mold 12 and elastically deformed, the mating surfaces 22 and 24 of the lower mold 12 and the upper mold 16 are brought into contact with each other. To seal.

  In this way, the seal between the mating surfaces 22 and 24 of the lower mold 12 and the upper mold 16 is sealed not only by the mating of the mating surfaces 22 and 24 but also by the cushioning material 28, so that the mating surface 22 is formed during foam molding. , 24 eliminates gas leakage. That is, the gas in the mold 10 is blocked from leaking outside by the buffer material 28. Therefore, even if the gas in the mold 10 has entered between the mating surfaces 22 and 24, the gas accumulates on the inner peripheral side 30 by the buffer material 28 and is compressed there. The foamed urethane stock solution M cannot enter the inner peripheral side 30 of 28. Therefore, generation | occurrence | production of a burr | flash can be prevented reliably.

  After foaming and curing the foamed urethane stock solution M in the foaming mold 10 in this way to form polyurethane foam, the upper mold 16 is opened, and the core mold 18 is separated from the lower surface of the upper mold 16 by the driving means 19. Thus, the sheet pad 1 can be taken out. Thereby, the pad 1 for sheets without a burr | flash in an outer peripheral part can be shape | molded.

  According to the manufacturing method of the foaming mold according to the present embodiment, since the mating surface 24 that can be in close contact with the mating surface 22 and the groove 26 for mounting the buffer material 28 are embossed, electrical discharge machining and machine precision It is possible to obtain a foaming mold having a dimensional accuracy equivalent to that obtained by processing and having excellent burr prevention properties. In addition, the foaming mold obtained in this way does not require electric discharge machining or mechanical precision machining that requires a great amount of time and cost, so that the production period and cost can be greatly reduced.

  In the present embodiment, the mating surface 24 and the groove 26 of the upper mold 16 are formed after the core mold 18 is assembled to the upper mold 16, but even before the core mold 18 is assembled to the upper mold 16. Good. That is, after the lower mold 12 and the upper mold 16 are assembled via the hinge portion 14, the mating surface 24 and the groove 26 of the upper mold 16 are formed as described above, and then the core mold 18 is replaced with the upper mold 16 May be assembled. Alternatively, the lower mold 12, the upper mold 16, and the core mold 18 are assembled after the mating surface 24 and the groove 26 of the upper mold 16 are formed before the lower mold 12 and the upper mold 16 are assembled through the hinge portion 14. May be. Further, in this embodiment, the curable resin layer 27 having the mating surface 24 and the groove 26 is disposed on the mating portion 25 provided on the upper mold 16. However, these are provided on the lower mold 12 instead of the upper mold 16. You can also. Further, in the above-described embodiment, the split mold is described. However, the present invention can be similarly applied to a split mold including only an upper mold and a lower mold. Furthermore, the present invention can be applied not only to a mold having a pair of upper and lower molds but also to a mold having a pair of left and right molds.

  The foam mold of the present invention and the manufacturing method thereof are suitable for a mold for a pad for a seat, which is a cushion body mainly used for an automobile seat. However, the present invention is not limited to this, and the cushion mold for various vehicles and homes. It can be used as a mold for various foamed molded articles, including pads used.

It is sectional drawing of the foaming mold which concerns on one Embodiment of this invention, (a) shows the state which opened the upper mold | type, (b) shows the state which closed the upper mold | type, respectively. It is sectional drawing which showed the foaming mold before a curable resin layer is arranged. (A)-(d) is a principal part expanded sectional view in the production process of a foaming mold. It is sectional drawing of the foaming shaping | molding die with which the shock absorbing material was mounted | worn, (a) shows the state which opened the upper mold | type, (b) shows the state which closed the upper mold | type, respectively. FIG. 5 is an enlarged cross-sectional view of a main part of FIG. 4, in which (a) shows the mating surface of the upper mold, and (b) shows a state in which the mating surface of the lower mold is mated. (A) is the perspective view seen from the front of the pad for sheets, (b) is the perspective view seen from the back surface.

Explanation of symbols

10 ... Foam mold 12 ... Lower mold (other mold)
16 …… Upper die (one side)
22 …… Molding surface of lower mold 24 …… Mating surface of upper mold 25 …… Matching portion 26 …… Groove 27 …… Curable resin layer 28 …… Buffer material 29 …… Convex member 1 …… Seat pad M… ... urethane foam stock solution

Claims (2)

In the manufacturing method of the foaming mold comprising a one-type mold and the other mold, wherein a groove for mounting a cushioning material is provided on the mating surface of the one mold among the mating surfaces of the one mold and the other mold.
A curable resin layer is disposed on the mating portion of the one mold, and a detachable convex member is disposed on the mating surface of the other mold. After the curable resin layer is cured by closing the mold in this state, the mold is opened. Thus, the foaming mold manufacturing method is characterized in that the one-side mating surface and the groove are formed in the curable resin layer. In a foam molding die comprising one mold and the other mold, wherein a groove for mounting a cushioning material is provided on the mating surface of one mold among the mating surfaces of the one mold and the other mold,
A foaming mold characterized in that a curable resin layer is disposed on the mating portion of the one mold, and the mating surface of the one mold and the groove are provided on the curable resin layer.

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