JPH06126413A - High speed injection casting device - Google Patents

Abstract

PURPOSE:To enable high speed injection, in which drawing cavity and running shortage are not developed even in the case of casting a thin formed product, by constituting this device so as to arrange plural injection pistons in pallel. CONSTITUTION:At first, molten aluminum is introduced into a cylinder 3. Thereafter, the pistons 4a, 4b shift into two directions in a cavity with pressurizing cylinders 5a, 5b to inject the molten aluminum into the cavity 2. Then molten aluminum is filled up into the cavity 2 at two times of the injection speed compared with the ordinary method. Therefore, even in the case of forming the thin formed body, the formed product without developing the drawing cavity and the running shortage can be obtd. Further, in the case of arranging two or more sprues in parallel, even if the total area of the sprue is equaled to the sprue area of the single piston, the filling ratio into the cavity is better than that in the case of the single piston.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casting device capable of high-speed injection for casting aluminum die casting and the like.

[0002]

2. Description of the Related Art Conventionally, as a method for performing high-speed injection, there is an invention described in, for example, JP-A-61-193763. The above invention detects a decrease in the speed of the injection piston immediately before the completion of filling and performs the pressure increasing operation by the pressure increasing piston.

[0003]

However, in the method of the prior art described above, in the case of molding a thin-walled molded product, the injection speed is insufficient even if a pressure boosting piston is provided, and a sink mark or short circuit occurs in the molded product. was there.

Therefore, the present invention was developed in view of the above-mentioned drawbacks of the prior art, and an object of the present invention is to provide a high-speed injection casting apparatus in which sink marks or shorts do not occur even when casting a thin molded product.

[0005]

The present invention is an injection casting apparatus having an injection piston provided in a cylinder, wherein a plurality of injection pistons are provided in parallel.

[0006]

In the present invention, the cavity can be filled at high speed. For example, if two pistons having the same diameter are pressurized at the same speed, the filling speed into the catty is doubled, and the molten metal can be filled into the cavity without further cooling. This can prevent the occurrence of sink marks and shorts.

[0007]

[Embodiment 1] FIG. 1 is a partial sectional view showing the present embodiment.
Reference numeral 1 is a mold having a cavity 2, and a cylinder 3 is fitted in the mold 1. Two independent pistons 4a and 4b are fitted in the cylinder 3 in parallel and slidably. Pressurizing cylinders 5a and 5b are connected to the pistons 4a and 4b, respectively.

The high-speed injection casting apparatus having the above structure is
First, molten aluminum is introduced into the cylinder 3 through a hole (not shown). After that, the pistons 4a and 4b are moved toward the cavity 2 by the pressurizing cylinders 5a and 5b (to the right in the drawing).
Then, the molten aluminum is injected into the cavity 2. At this time, the cavity 2 is filled at an injection speed twice as high as usual.

According to this embodiment, it is possible to perform molding without sink marks or shorts even when molding a thin molded body. In addition, when two or more gates are provided in parallel, even if the total area of the gates is equal to the area of the gate of a single piston, the filling rate into the cavity is better than that of a single piston.

[0010]

Second Embodiment FIG. 2 is a partial sectional view showing the present embodiment.
In the present embodiment, the cylinder 3 in the first embodiment is eliminated, and instead, a cylinder 11 in which two pistons 4a and 4b can be arranged in a V-shape that converges in the direction of the cavity 2 is used. However, other configurations are composed of the same components, and the same components are designated by the same reference numerals and the description of the components is omitted.

The high-speed injection casting apparatus having the above structure is
By arranging the two pistons 4a and 4b in a V shape, the gate can be provided close to each other. In addition, the diameter of the pressurizing cylinders 5a and 5b can be increased.

According to the present embodiment, it is possible to perform injection at a higher speed than in the first embodiment, and it is possible to form a thinner molded product.

[0013]

[Embodiment 3] FIG. 3 is a partial sectional view showing the present embodiment.
In this embodiment, the two pistons 4 in the first embodiment are used.
It is different in that it is configured so that a position difference δ is added to a and 4b, and other configurations are composed of the same configuration parts, and the same numbers are given and description of the configuration is omitted.

The high-speed injection casting apparatus having the above structure is
The piston 4a is provided with a position difference δ on the cavity 2 side with respect to the piston 4b, and the piston 4a moves in a push-down manner.

According to this embodiment, the capacity of the biscuit portion 21 is halved, so that the material can be effectively used.

Although two pistons are used in each of the above embodiments, the present invention is not limited to this.
A plurality of three or more pistons can be used as required.

[0017]

As described above, according to the high-speed injection casting apparatus according to the present invention, it is possible to obtain a high-speed casting apparatus which does not cause sink marks or shorts by utilizing the conventional pressure cylinder.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing a first embodiment.

FIG. 2 is a partial cross-sectional view showing a second embodiment.

FIG. 3 is a partial sectional view showing a third embodiment.

[Explanation of symbols]

 1 type 2 cavity 3 cylinder 4a, 4b piston 5a, 5b pressurizing cylinder

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takuya Kodama 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd.

Claims (1)

[Claims] 1. A high-speed injection casting apparatus, comprising a plurality of injection pistons arranged in parallel in an injection casting apparatus having an injection piston provided in a cylinder.