JPH0740118U - In-mold foam molding Mold slit - Google Patents

Abstract

(57) [Summary] [Purpose] As a slit for in-mold foam molding dies, it is intended to have excellent wear resistance, impact resistance, lubricity, and chemical resistance, and at the same time reduce manufacturing costs. [Structure] Synthetic resin material in which abrasion-resistant material is mixed in slit S for foam molding in a mold in which a cylindrical portion 1 and a bottomed cylindrical body having a bottom surface 2 at one end surface are provided with a plurality of pores 3 in the bottom surface 2. It is formed by the molded body of.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a slit which is used by driving into a small hole for distribution of steam or the like in an in-mold foam molding die.

[0002]

[Prior art]

 As shown in FIG. 3, in-mold foam molding is performed by using a thermoplastic resin such as polystyrene called beads in a cavity 13 formed by a mold made of both concave and convex molds A and B attached to a fixed frame 11 and a movable frame 12. The pre-expanded particles of the above are filled through the auto feeder 21, steam is introduced from the fluid inlets 14 and 15 and jetted from the spray nozzle 16 to heat-melt the pre-expanded particles, and after the fusion, the cooling water is introduced. This is a molding mode in which the mold is cooled and the product is taken out. For taking out the molded product, an eject pin 18 having a spring 19 and an adjustment pin 20 is attached to the cavity bottom plate of the concave mold B by a pin holder 17.

A plurality of molding dies including the convex mold A and the concave mold B as described above are usually arranged in the vertical and horizontal directions so that a plurality of products can be obtained at one time. A and concave mold B have a plurality of slits S so that steam does not penetrate into the bead evenly and heats and melts uniformly to promote heating and melting without being limited to heating the molding surface in contact with the mold. Is fitted into the small hole.

The slit S is generally made of a metal material such as brass, aluminum or stainless according to the mold material, and is formed into a bottomed cylindrical body having a bottom surface having a plurality of holes at one end surface by cutting. Has been done.

[0005]

[Problems to be solved by the device]

 However, the slits made of metal materials as described above often melt the beads when used for in-mold foam molding and excessively heat them, and the molded product bites and catches, increasing clogging and producing burrs. However, there is a problem that the appearance is deteriorated.

Therefore, when repairing the mold, the slits are usually replaced at the same time. For this replacement work, a round bar is used from the inner surface of the mold to punch out the old slit, and then a new slit is driven in using a hammer. If the small holes for slits are large and loose, the slits are tapped lightly with a hammer to form an elliptical shape, but with the increase in the number of replacement work, the cost of conventional metal material slits is economical because of the cost. There is a problem with.

The present invention addresses the above situation, pays attention to the reduction of molding cost by using a synthetic resin material, and simplifies the molding, and at the same time, wear resistance, impact resistance, lubricity, The object is to provide a slit having excellent properties such as chemical properties.

[0008]

[Means for Solving the Problems]

 In order to achieve the above object, in the present invention, a cylindrical bottomed cylinder having a bottom surface at the one end surface is provided with a slit having a plurality of pores in the bottom surface, and is formed by a molded body of a synthetic resin material mixed with an abrasion resistant material.

Here, the synthetic resin material for forming the slit is preferably a thermoplastic synthetic resin, and examples thereof include vinyl chloride, nylon, polyester, polyethylene, polypropylene, aramid, etc., but polycarbonate resin, acetal resin, etc. The known synthetic resin for molding may be used.

As the wear resistant material, molybdenum, carbon powder, etc. can be used alone or in combination of two or more kinds. Among them, those having excellent lubricity are preferable, and the purpose thereof can be adjusted by mixing an appropriate amount. Can be reached.

It should be noted that the pores provided on the bottom surface may be slit-shaped or may be provided as a plurality of small holes.

[0012]

[Action]

 When using the slit according to the present invention, when it is fitted into the slit hole of the mold, for example, in the case of a 10φ slit hole, a hole is drilled using a 9.7 to 9.8φ cone and the slit hole is lightly hammered. By hitting and fitting, the flexible resilience inherent in the synthetic resin material ensures that it is fitted into the slit hole.

When replacing the slit, punching is performed using a round bar as in the conventional case. However, both fitting and withdrawing have better slipperiness than metal materials and are easy to insert and remove.

Moreover, during in-mold foam molding, bead plucking due to excessive heat does not occur, clogging at the slits is reduced, and product cost is reduced by using injection molding and the like, which is economical. Improve sex.

[0015]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1A and 1B show an example of a slit of the present invention, in which S is a slit composed of a cylindrical portion 1 and a bottom face 2 at one end face thereof, and a bottom face 2 is shown in FIG. As shown, a plurality of elongated slit strips 3 are provided.

The slit S is formed by injection molding of a nylon resin mixed with molybdenum and carbon powder, and the number and shape of the slit strips are not necessarily fixed, but may be any number and any shape.

2 (a) and 2 (b) show a case in which the pores of the bottom surface 2'at one end of the cylindrical portion 1'of the slit S are a plurality of circular small holes 3 ', and the small holes 3'radiate from the central portion. It is provided in. In this case as well, it is molded by injection molding of thermoplastic synthetic resin mixed with wear resistant material such as molybdenum and carbon powder, and the number of small holes and the shape of the holes are not fixed, but any number and other such as square holes can be used. It may have a shape, but it is preferable to arrange them at substantially equiangular angles on the same circumference.

In each of the above examples, it is preferable that the wall thickness of the cylindrical portion 1, 1 ′ and the bottom surface 2, 2 ′ be substantially the same as that of the conventional metal material.

[0020]

[Effect of device]

 As described above, the present invention is a slit for molding a synthetic resin material mixed with a wear resistant material, and by using injection molding, the manufacturing cost of the slit can be significantly reduced compared to the conventional slit made of a metal material. In addition, it is possible to use not only abrasion resistance but also chemical resistance, impact resistance and slipperiness by using a synthetic resin material mixed with abrasion resistant material, making it easy to punch into die slit holes and punch. it can .

Further, since it is made of a synthetic resin material, even if too much heat is applied during heating by introducing steam, the beads will be melted like a metallic material, the product will not be eaten in, burrs will not be generated, and the lubricity will be good. As a result, the mold release is smooth and there is an advantage that the appearance of the product is not deteriorated.

[Brief description of drawings]

FIG. 1 is a view showing an example of a slit according to the present invention,
(A) is a bottom view and (b) is a longitudinal sectional view.

2 is another embodiment of the slit according to the present invention, (a)
Is a bottom view and (b) is a vertical sectional view.

FIG. 3 is a partially cutaway side sectional view showing an in-mold foam molding die device using a slit according to the present invention.

FIG. 4 is a partially enlarged cross-sectional view showing an aspect of slit arrangement.

[Explanation of symbols]

 S Slit 1,1 'Cylindrical part 2,2' Bottom surface 3,3 'Pore

Claims (1)

[Scope of utility model registration request] 1. An in-mold foam molding die characterized in that it is made of a synthetic resin material mixed with an abrasion resistant material, and a bottomed cylindrical body having a bottom surface at one end surface is provided with a plurality of pores. Slits.