JPH08168866A - Pressure pin device - Google Patents

Abstract

PURPOSE: To shorten the arranging time of a metallic mold and to improve the productivity by fitting a hydraulic device for operating pressure pins to a fixed die plate and arranging the pressure pin device on the metallic mold side while breaking it up. CONSTITUTION: In the case of partially pressurizing a formed product during pressure casting by using the metallic mold 6, the push-out plate 3 guided with two guide bars 5 is pressed to a pressure plate 8 with a hydraulic cylinder 2 and the pressure pins 7 fixed to the pressure plate 8 are pushed in just before solidifying to reduce or eliminate casting cavity. After completing the partial pressurization with the pressure pins 7, at the time of retracting the hydraulic cylinder 2, the pressure plate 8 is returned back with springs 9 attending the retraction. At this time, the pressure plate 8 collides against a stopper 10 to be stopped. Therefore, the pressure pin device is fitted to the fixed mold plate 1, and since the pressure plate 8 fixed with the pressure pins 7 is fitted to the metallic mold 6 side, the pressure pins 7 can be fitted to the desired position matching the metallic mold 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a local pressure pin device for controlling the stroke value during pressure casting to reduce or eliminate porosity.

[0002]

2. Description of the Related Art Conventionally, when a casting is produced by a pressure casting method using a die, the volume of the molten metal injected into the cavity of the die shrinks when it is cooled and solidified.
Cause inward shrinkage.

Further, since the molten metal is injected at a high speed, air is entrained in the molten metal to form porosity inside the casting.
In order to eliminate defects such as internal shrinkage and the formation of porosity, a method has been adopted in which the pressure pin is projected into the cavity immediately before the molten metal in the cavity is solidified.

As an example, Japanese Utility Model Laid-Open No. 61-167258 (referred to as Kokoku) and Japanese Utility Model Laid-Open No. 1-299753 (referred to as Otsuku) show conventional pressurizing pin devices for die casting machines. The first publication discloses a pressure pin device for a vertical die casting machine, and the second publication discloses a pressure pin device for a horizontal die casting machine. Further, in both Kokoku and Kotsu gazette, a pressure pin device including a hydraulic cylinder is attached to the die on the moving die plate side.

[0005]

According to the prior art, there were the following technical problems.

[0006] Both the first and second publications are mobile die presses.
Since the pressure pin device including the actuator is attached to the die on the upper side, it is necessary to manually remove the hydraulic cylinder from the die when exchanging the die.

Further, if the hydraulic cylinder and the pressurizing device are built in each mold, the cost of the pressurizing pin device becomes expensive. Further, since the hydraulic cylinder is attached to the die on the moving die plate side, the stroke of the hydraulic cylinder is limited, so that not only the number of pressurizing pins is limited but also there is a problem in maintenance.

Further, if a pressure pin device including an actuator is attached to the die on the moving die plate side, the length of the pipe from the hydraulic device to the die on the moving die plate side becomes long, resulting in pressure loss. Not only is there a problem, but there is a problem such as an increase in cost.

According to the present invention, the pressure pin is actuated in order to reduce or eliminate the porosity by pressing the pressure pin with the hydraulic cylinder immediately before solidification on the molded product under pressure casting using the mold. By providing a hydraulic device on a fixed die plate and providing a pressure pin device separately on the mold side, the mold setup time can be shortened, and a pressure pin device that can improve productivity is provided. To do.

[0010]

In order to solve the above problems, the pressure pin device of the present invention has the following means.

In a pressure pin device in which a pressure pin is pressed by a hydraulic cylinder immediately before solidification to reduce or eliminate a porosity, a fixed die pre-press is applied to a molded product under pressure casting using a die. A hydraulic cylinder for actuating the pressurizing pin is mounted on the press side, and an extruding plate is fixed to the rod tip of the hydraulic cylinder, and at least two guide bars are fixed to the extruding plate. Supporting so as to be guided by the fixed die plate, and a pressurizing pin for fixing the local pressurization with a spring interposed between the mold and the pressurizing plate on the mold side. A plate is provided so as to be movable back and forth toward the cavity of the mold, and a stopper for preventing the pressurizing plate from being separated from the mold side is provided on the mold side. The pressure plate is configured to abut It was.

[0012]

The operation of the pressure pin device of the present invention constructed as described above will be described below.

In order to reduce or eliminate the porosity, a hydraulic cylinder pushes an extrusion plate against a molded product under pressure casting using a die, and the extrusion is guided by two guide bars. Press the plate against the pressure plate and press
Press the pressure pin fixed to the tray just before solidification.

Next, after the pressurizing step with the pressurizing pin is completed,
When the hydraulic cylinder is retracted, the pressurizing plate is returned by the spring along with this and stops against the stopper.

Therefore, since the pressurizing pin is pushed by the hydraulic cylinder immediately before the solidification to locally pressurize the molded product under pressure casting, the porosity is reduced or eliminated.

[0016]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a partial cross-sectional view showing a mold clamping portion of a horizontal mold clamping vertical injection die casting machine as viewed from the side, showing a state before mounting a mold. FIG. 2 is a partial cross-sectional view showing the mold clamping portion, showing a state after the mold is mounted.

In FIG. 1, a fixed die plate 1 is equipped with a hydraulic cylinder 2 for operating a pressure pin. An extrusion plate 3 is fixed to the tip of the rod 2a of the hydraulic cylinder 2, and at least two guide bars 5 are attached to the extrusion plate 3.
Is fixed and is supported so as to be guided through a bush 3a provided on the fixed die plate 1.

FIG. 2 shows a state in which a pair of molds 6 are mounted on the fixed die plate 1 and the movable die plate 4, respectively. In the figure, a concave portion is formed on the back surface of the mold 6, and a spring 9 is interposed between the mold 6 and the pressure plate 8 on the mold 6 side to form a pressure pin for local pressure. A pressure plate 8 to which the pressure plate 7 is fixed is provided to be movable back and forth toward the cavity 6a of the mold 6, and a stopper 10 for preventing the pressure plate 8 from coming off from the mold 6 side is provided. It was provided on the side, and the extrusion plate 3 and the pressure plate 8 were in contact with each other.

A stopper 22 is provided on the die 6 side so that the spring 9 is not compressed more than necessary by the pressure plate 8.

The operation of the pressure pin device of the present invention will be described.

First, at the start of the work, as shown in FIG. 2, a pair of molds 6 are attached to the fixed die plate 1 and the movable die plate 4 from the state before mounting the molds in FIG. Put on.

The plunger chip 20a is injected into the injection sleeve 2
1, and hot water is supplied from a hot water supply device (not shown), and the injection cylinder 20 is operated to inject it into the cavity 6a of the die 6 for pressure casting.

Next, in the case of locally pressurizing the molded product under pressure casting using the die 6, the extrusion plate 3 guided by the hydraulic cylinder 2 to the two guide bars 5 is used. Is pressed against the pressure plate 8 and the pressure pin 7 fixed to the pressure plate 8 is pressed immediately before solidification to reduce or eliminate the porosity. At this time, the pressure plate 8 abuts against the stopper 22, and the spring 9 is protected by the stopper 22 so that the spring 9 is not compressed more than necessary.

When the hydraulic cylinder 2 is retracted after the local pressurization by the pressurizing pin 7 is completed, the pressurizing plate 8 is returned by the spring 9 accordingly. At this time, the pressure plate 8 and the stopper 10 collide with each other and stop.

The pressure pin device of this embodiment is a fixed die press.
Since the pressure plate 8 having the pressure pin fixed to the mold side can be mounted on the mold, the pressure pin can be positioned at a desired position according to the mold without being restricted by the shape of the mold. Since it can be mounted, the mold setup time can be shortened as compared with the conventional technique, and the productivity can be improved.

Further, since a plurality of pressure pins can be simultaneously operated by one actuator, it can be manufactured at low cost.

[0028]

The pressure pin device of the present invention is a fixed die press.
It can be mounted on a mold and a pressure plate with a pressure pin fixed to the mold side, so without being restricted by the mold shape,
Since the pressure pin can be attached to the desired position according to the mold,
The die setup time can be shortened as compared with the conventional technique, and the productivity can be improved.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a horizontal mold clamping vertical injection die casting machine as viewed from the side showing a mold clamping portion before mounting a mold.

FIG. 2 is a partial cross-sectional view showing the mold clamping part after the mold is mounted, as seen from the side of the horizontal mold clamping vertical injection die casting machine.

[Explanation of symbols]

 1 Fixed Die Plate 2 Hydraulic Cylinder 3 Extrusion Plate 4 Moving Die Plate 6 Die 7 Pressure Pin 8 Pressure Plate 9 Spring 10 Stopper 22 Stopper

Claims (1)

[Claims] 1. A pressure pin device for fixing a molded product, which is being pressure-molded using a mold, by a hydraulic cylinder to press the pressure pin immediately before solidification to reduce or eliminate the porosity. On the die plate side, a hydraulic cylinder for operating the pressurizing pin is mounted, and an extruding plate is fixed to the rod tip of the hydraulic cylinder, and at least two guide bars are fixed to the extruding plate. And supported so as to be guided by the fixed die plate, and a pressure pin for local pressure was fixed on the mold side with a spring interposed between the mold and the pressure plate. A pressing plate is provided so as to be movable back and forth toward the cavity of the mold, and a stopper for preventing the pressing plate from coming off from the mold side is provided on the mold side. And the pressure plate contact each other A pressure pin device characterized in that