JPH06218773A - Injection molding device - Google Patents

Abstract

PURPOSE:To produce high-quality resin product such as a cartridge and the like and contrive improvement in moldability and cost. CONSTITUTION:When a resin product is molded in a mold 2 through a resin supplying gate 5, a core pin 21 is arranged adjustably in a resin reservoir 20 opposed to the gate 5 whereby faulty molding and/or faulty appearance, which are due to shrinkage cavities, can be eliminated, various characteristics required for a resin product such as a cartridge or the like can be satisfied, beautiful appearance and good presentation can be obtained, a high-quality product can be produced, productivity is also improved and improvement in cost can be contrived.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for molding a cartridge, and more particularly to an injection molding apparatus for manufacturing resin molded products such as tape cassettes and disk cartridges with male and female molds.

[0002]

2. Description of the Related Art Conventionally, in this type of molding die, a resin supply gate is provided in the die, and resin injected through the gate is introduced to form a case body as a product in the cavity. It is known to be molded. Then, in this type of injection molding die, as shown in FIG. 5, a cavity portion a is formed by a fixed side mold plate b and a movable side mold plate d having a core c, and a resin pool e is formed in this core. Is often used to face the gate f.

[0003]

However, the resin pool e (slug well) provided in this conventional injection molding die is subject to molding conditions such as the type of resin material, the shape of the gate, and the way of mounting the gate. Although an optimum material pool is produced, a small resin pool portion having a small pool amount is previously prepared, and the actual molding is performed while adjusting the additional size by cutting to an appropriate size. But,
Conventionally, a resin pool portion e provided to face the gate f
Since it is directly engraved on the movable core c, if it is over-processed too much, it cannot be redone, resulting in sink marks or burns or strange flow marks on the product. There are problems that defects and appearance defects are likely to occur, the appearance is not noticeable, the appearance and product value are reduced, and the moldability is also deteriorated. The present invention is intended to eliminate these conventional drawbacks, the amount of accumulation can be adjusted, there is no molding defect or appearance defect due to sink marks, and various characteristics required for resin products such as cartridges can be satisfied, and the appearance is The purpose of the present invention is to provide an injection molding machine that is clean, good in appearance, and capable of producing high-quality products, and that can improve productivity and cost. It is what

[0004]

The present invention is characterized in that, in an injection molding apparatus having a resin supply gate in a mold, a resin pool forming core pin opposed to the gate is adjustably arranged. Injection molding apparatus.

[0005]

In the injection molding apparatus having the resin supply gate in the mold, the resin pool forming core pin opposed to the gate is arranged so as to be adjustable, so that the amount of the resin pool can be easily adjusted. Moldability can be greatly improved and the appearance can be made beautiful, that is, there are no molding defects and appearance defects due to sink marks, the various characteristics required for resin products such as cartridges can be satisfied, and the appearance is beautiful. In addition, it is possible to produce a product with good appearance and high quality, which improves the productivity and also the cost.

[0006]

1 and 2, a resin supply sprue bush 3 is provided in a mold 2 for molding a case body 1 of a cartridge, and a runner communicating with the sprue bush 3 is provided. When the case body 1 is molded in the cavity portion 6 through the gate 4 and the gate 5, the resin pool 2 provided opposite to the gate 5 as a pinpoint gate.
0 is provided with a core pin 21 so that the core pin 21 can be adjusted freely to form an injection molding device.

The gate 5 is one of a pinpoint gate, a direct gate, and a direct hot runner provided on the stationary mold plate 10, and the mold 2
It is preferable that the movable side template 11 is provided at a position facing the core pin 21 that is replaceably fitted and arranged.

The embodiment shown in FIG. 3 is applied to the direct gate type, in which the resin reservoir 20 is provided in opposition to the resin injection passage of the sprue bush 3 and the core pin 21 is arranged so as to be adjustable.

In the embodiment shown in FIG. 4, the mold is used for a direct hot runner mold, and the resin reservoir 20 is provided in opposition to the resin injection passage of the hot runner 22, and the core pin 21 is arranged so as to be adjustable.

In the figure, 12 is a knockout pin, 13 is a locate ring, 16 is a receiving plate, and 18 is an ejector guide pin.

[0011]

INDUSTRIAL APPLICABILITY According to the present invention, in an injection molding apparatus having a resin supply gate in a mold, a resin pool forming core pin opposed to the gate is provided so as to be adjustable, so that molding defects due to sink marks and It has no appearance defects, can satisfy various characteristics required for resin products such as cartridges, has a beautiful appearance, good appearance, and can produce high quality products. Can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is an enlarged vertical sectional view of a part of the example of FIG.

FIG. 3 is a vertical sectional view of another embodiment of the main part of the present invention.

FIG. 4 is a vertical sectional view of still another embodiment of the essential part of the present invention.

FIG. 5 is a vertical cross-sectional view of a main part of a conventional example.

[Explanation of symbols]

 1 Case Main Body 2 Mold 3 Sprue Bushing 4 Runner 5 Gate 6 Cavity 10 Fixed Side Mold 11 Movable Side Mold 20 Resin Pool 21 Core Pin

Claims (2)

[Claims] 1. An injection molding apparatus having a resin supply gate in a mold, wherein a resin puddle forming core pin opposed to the gate is arranged so as to be adjustable. 2. The core pin, wherein the gate is one of a pinpoint gate, a direct gate, and a direct hot runner, and the core pin is slidably or replaceably fitted to the movable mold plate of the mold. The injection molding device according to claim 1, wherein the injection molding device is provided at opposite positions.