JPH07259Y2 - Foam mold - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a foam molding product made of polyurethane foam or the like, for example, a foam molding die for a seat cushion, a seat back or the like for automobiles.

(Prior Art) Conventionally, for molding of the foam molded article, a foam molding die 14 including an upper mold 10 and a lower mold 12 as shown in FIG. 4 is used, and a liquid foaming raw material such as a polyurethane foam raw material is placed in a cavity 16 thereof. After injecting and foaming into cavity shape, upper mold 10 and lower mold
This is done by separating 12 and taking out the foam molded product from the foam molding die 14.

By the way, a seat cushion or the like, which is a molded product, usually has a complicated three-dimensional shape, and at the time of molding, the foaming mold has a split mold structure that does not form an undercut as much as possible. Therefore, the split surface of the foam molding die 14, that is, the mating surface 18 of the upper die 10 and the lower die 12 is also usually three-dimensionally changed.

However, in such a foam molding die 14, it is difficult to secure the sealing property at the mating surfaces 18 of the upper die 10 and the lower die 12, that is, the consistency of the die, and the liquid foaming raw material leaks from the mating surfaces to foam. Burrs are often created around molded parts.

Therefore, as shown in FIG. 5, a sealing material 20 made of an elastic foam or the like is attached to the mating surface 18 of the lower mold (or the upper mold) with an adhesive tape or the like, and the sealing property of the sealing material 20 on the mold mating surface It has become possible to increase the efficiency and prevent burrs from occurring.

However, in that case, it is difficult to attach the sealing material 20 to the correct position, and the adhesive force of the adhesive tape or the like decreases due to the release agent applied to the foam molding die or the heat during foam molding. There has been a problem that the displacement of the sealing material 20 or peeling of the sealing material is likely to occur, and the sealing property of the foaming mold becomes insufficient in a short period of time.

Further, it is possible to form a concave groove 22 as shown in FIG. 6 in the mold matching surface 26 of the foam molding die 24 and fit the sealing material 28 into the concave groove 22. -180508 gazette etc. are disclosed.

However, the foaming mold has the following problems. One of them is that the work of forming a groove in the foam molding die is more complicated and complicated than the work of simply cutting a part of the foam molding die, which makes it difficult to manufacture the foam molding die Is to increase. In addition, the inside of the groove 22 and the groove
Since the openings of 22 have substantially the same size, there is also a problem that the sealing material 28 easily comes off from the concave groove 22 when the upper mold and the lower mold are separated, that is, when the foamed molded product is taken out.

It is possible to make the inside of the concave groove 22 larger than the opening of the concave groove (make the concave groove an under shape) to make it difficult for the sealing material to come off from the concave groove. However, there is a problem that the shape of the groove becomes difficult. Also,
It has also been proposed to make a hole in the bottom of the groove and fix the sealing material to the bottom of the groove with a bolt or the like, but in that case, the production of the foaming mold becomes more troublesome.

(Problems to be solved by the invention) Therefore, in view of the above points, this invention provides a foam molding die that allows the seal material to be attached at a correct position, and that the seal material does not shift or come off and is easy to manufacture. It is intended to be provided.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a foam molding die including an upper die and a lower die, having a cavity inside.
The part between the mold matching surface and the cavity periphery is a slanting sealing surface between the upper die and the lower die, and a protrusion toward the sealing surface of the upper die is formed at the lower end of the sealing surface of the lower die, and the inner peripheral edge is the upper side. A plate-shaped frame die protruding toward the seal surface of the die is detachably attached to the die mating surface of the lower die, and the inside formed by the projecting inner peripheral edge of the frame die and the protrusion at the lower end of the seal surface is enlarged. The elastic sealing material is fitted in the groove having a substantially trapezoidal cross section.

(Function) The groove formed by the protruding inner peripheral green of the frame die mounted on the die matching surface of the lower die and the protrusion at the lower end of the lower die sealing surface has a substantially trapezoidal cross-sectional shape with an enlarged inside. For,
The elastic seal material fitted in the groove does not come off from the groove even when the foaming mold is separated.

Further, the replacement of the elastic seal material can be easily performed by removing the frame die.

On the other hand, in the production of the foaming mold, since it is not necessary to form the fitting groove for fitting the elastic sealing material on the sealing surface, the foaming mold can be easily manufactured.

(Embodiment) An embodiment of the present invention will be described below.

FIG. 1 is a sectional view of a foaming mold according to an embodiment,
FIG. 3 is a cross-sectional view of the foaming mold before fitting the elastic sealing material, and FIG. 3 is a perspective view showing a part of the lower mold when the frame mold is attached to the lower mold.

The foam molding die 30 is composed of an upper die 32 and a lower die 34, and has a cavity 36 having a product shape inside, and has a die mating surface.
Upper mold 32 and lower mold 34 are located between 38, 40 and the periphery of cavity 36.
The sealing surfaces 42 and 44 are formed between them.

The upper and lower mold sealing surfaces 42, 44 are inclined so as to spread outward from the periphery of the cavity 36 toward the mold mating surfaces 38, 40,
At the lower end of the lower mold sealing surface 44, a protrusion 46 facing the upper mold sealing surface 42 is formed.

At the upper end of the sealing surfaces 42 and 44, a substantially horizontal mold matching surface 3
8, 40 extend outwardly, and a plate-shaped frame die 48 having an inner peripheral edge 47 protruding toward the upper die sealing surface 42 is detachably attached to the die mating surface 40 of the lower die with screws or the like. An inner peripheral edge 47 of the frame die 48 and the projection 46 at the lower end of the sealing surface form a groove 50 having a substantially trapezoidal cross-section with an enlarged inside, on the lower sealing surface as shown in FIG. .

Then, an elastic sealing material 52 made of silicon rubber or the like is fitted into the groove 50 to form the foam molding die 30.

The elastic seal material 52 is formed by filling the groove 50 formed by the frame-shaped inner peripheral edge 47 and the protrusion 46 with a curable resin and curing the resin in the groove 50, so that the seal material 52 is formed at the same time. The groove
It may be fitted to 50, or a band-shaped elastic seal material is molded from silicon rubber or the like in advance, so that when the frame die 48 is attached to the die matching surface 40 of the lower die, it is fitted in the groove 50. Good.

On the other hand, the elastic seal material 52 can be easily replaced by removing the frame die 48 from the die matching surface 40 of the lower die.

Further, the groove 50 does not necessarily have to be provided all around the cavity 36, and may be partially provided at a portion where the liquid foaming raw material injected into the cavity 36 easily leaks.

(Effect) As described above, according to the present invention, a groove having an enlarged shape is formed in the seal surface by the protrusion formed at the lower end of the seal surface and the frame mold detachably attached to the mold matching surface, Since the elastic sealing material is fitted in the groove,
It is possible to prevent the sealing material from shifting in position and coming off, and it is possible to maintain high sealing performance for a long period of time. As a result, there is an effect that a foam-molded product without burrs can be stably manufactured.

Further, in the foam molding die of the present invention, since it is not necessary to engrave the concave groove for holding the elastic sealing material on the mold matching surface, the foam molding die can be easily manufactured, and the mold manufacturing labor and the manufacturing cost are reduced. There is an effect that can be done.

Further, the foaming mold of the present invention has an effect of facilitating repairing of the foaming mold because the frame mold which is an obstacle can be removed when repairing the cavity surface and the like.

[Brief description of drawings]

FIG. 1 is a sectional view of a foaming mold according to an embodiment of the present invention, FIG. 2 is a sectional view of the foaming mold before fitting an elastic sealing material, and FIG. 3 is a frame mold for the foaming mold. FIG. 4 is a perspective view showing a part of the lower mold for mounting, and FIGS. 4 to 6 are sectional views of a conventional foaming mold. 28: Elastic seal material, 30: Foaming mold, 32: Upper mold, 34: Lower mold,
36: cavity, 38: upper die mating surface, 40: lower die mating surface, 42: upper die sealing surface, 44: lower die sealing surface, 46: protrusion, 47: inner peripheral edge of frame die, 48 : Frame type, 50: Groove

Claims (1)

[Scope of utility model registration request] 1. A foam molding die comprising an upper die and a lower die, and having a cavity inside, wherein a mating surface of the upper die and the lower die and a peripheral edge of the cavity are obliquely oriented between the upper die and the lower die. As a sealing surface, the lower die sealing surface has a lower end with a protrusion toward the upper die sealing surface, and a plate-shaped frame die whose inner peripheral edge projects toward the upper die sealing surface. It is detachably attached to the upper part, and the elastic seal material is fitted in a groove having a substantially trapezoidal cross section in which the inside formed by the protruding inner peripheral edge of the frame shape and the protrusion at the lower end of the sealing surface has an enlarged shape. A characteristic foaming mold.