JPH0328993Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a device for changing a casting piston or a piston ring in a hot chamber die-casting machine.

[Prior Art] As is well known, the casting piston in a hot chamber die-casting machine is fitted into a casting cylinder fixed to a gooseneck that is immersed in the molten metal in the furnace. The casting piston rod is operated by an injection cylinder and an injection piston disposed outside the molten metal to deliver the molten metal to the mold outside the furnace.

Conventionally, the cast-in piston and piston ring have been replaced manually in the following manner. (1) When replacing the piston ring, remove the casting piston from the casting cylinder in the gooseneck and replace the ring while lifting it above the molten metal in the furnace.

(2) That is, when replacing the casting piston, remove the casting piston rod from the coupling and pull out the casting piston from the casting cylinder inside the gooseneck. The replaced casting piston is then placed into the casting cylinder within the gooseneck, which is submerged in the molten metal (and therefore invisible), and the casting piston rod is attached to the coupling.

Currently, these manual tasks are performed relying on experience and intuition.

[Problems to be solved by the invention] Conventionally, casting pistons and piston rings have been replaced by inefficient manual work, but this work is also very difficult as it involves overlapping the molten metal in the furnace. It also had the disadvantage of being extremely dangerous as it was carried out in an environmentally friendly environment.

The purpose of this invention is to improve the conventional inefficient manual work by automatically attaching and detaching the casting piston from inside the Gooseneck casting cylinder, making it easy to replace the casting piston and piston ring. An object of the present invention is to provide a device for replacing a casting piston in a hot chamber die-casting machine.

[Means and effects for solving the problem] In the present invention, the operating stroke of the injection piston inside the injection cylinder is adjusted, and when replacing the casting piston, the injection piston is raised to a position outside the molten metal on the furnace. A stroke adjusting piston is provided to move the piston, and the casting piston is automatically pulled out from the casting cylinder in the gooseneck.When inserting the casting piston into the gooseneck cylinder, the stroke adjusting piston is used. The stroke of the injection piston is moved back to the position where it returns to its normal operating state.

[Example] The present invention will be explained below with reference to the illustrated example. FIG. 1 is a cross-sectional view of a casting piston exchange device in a hot chamber die-casting machine showing an embodiment of the present invention, in which a gooseneck 2 is disposed immersed in the molten metal 1 in the furnace. A casting cylinder 3 is fixed to this. The upper surface of the casting cylinder 3 is sunk below the upper surface of the molten metal 1, and a piston ring 4 is disposed inside the casting cylinder 3, and a casting piston is fixed to the tip of a casting piston rod 6. 5 is inserted so that it can move up and down. The piston rod 6 extends above the surface of the molten metal, and its upper end is connected via a coupling 7 to the lower end of an injection piston 8 extending from the injection cylinder 9. The injection piston 8 is above the furnace, and the gooseneck 2 is placed on the upper surface of the molten metal.
The injection cylinder 9 is fitted into the lower part of the injection cylinder 9, which is disposed corresponding to the injection cylinder 9, so as to be vertically movable.

A stroke adjustment piston 10, which is a stroke adjustment member, is disposed directly above the injection piston 8 in the injection cylinder 9 so as to be able to move up and down within the pressurizing chamber 9a. The above pressurized chamber 9
a is a lower pressurizing chamber 9b in which the injection piston 8 is raised;
and an upper pressurizing chamber 9c for lowering the piston 8, and the upper and lower side walls of the chamber 9a are provided with supply and discharge ports 9d and 9e for a hydraulic device 11 having a directional switching valve. There is. Further, the upper pressurizing chamber 9c and the lower pressurizing chamber 9b are also respectively provided with supply/discharge ports (not shown) to which a hydraulic device (not shown) having a directional switching valve is connected.

Further, the stroke adjusting piston 10 has a flange portion 10a for position regulation on its outer periphery, and also has a through hole 10b in its central shaft portion communicating with the upper pressurizing chamber 9c.

In the device of this embodiment configured as described above, hydraulic pressure is applied from the hydraulic device 11 to the pressurizing chamber 9a through the supply/discharge port 9d, so that the stroke adjusting piston 10 moves to the flange 10a.
The lower surface of the pressurizing chamber 9a is regulated in a lowered position until it comes into contact with the bottom surface of the pressurizing chamber 9a. Therefore, in this state, the feeding operation of the molten metal 1 is performed as follows. That is, by pressurizing the lower pressurizing chamber 9b, the injection piston 8 rises until its upper surface abuts the lower surface of the stroke adjustment piston 10, and thereby the casting piston 5 also rises within the casting cylinder 3. . Next, when the upper pressurizing chamber 9c is pressurized, the injection piston 8 is lowered through the through hole 10b, so that the casting piston 5 is lowered within the casting cylinder 3, and the molten metal 1 is fed through the gooseneck 2.

When replacing the piston ring 4 or the cast piston 5, the direction switching valve of the hydraulic device 11 is operated to switch the oil supply direction, and hydraulic pressure is applied to the pressurizing chamber 9a through the supply/discharge port 9e. Then, as shown in FIG. 2, the stroke adjusting piston 10 is placed in a raised position until the upper surface of the flange portion 10a comes into contact with the upper wall surface of the pressurizing chamber 9a. When the lower pressurizing chamber 9b is pressurized in this state, the injection piston 8 rises significantly to a position where its upper surface abuts the lower surface of the stroke adjustment piston 10.
As a result, the casting piston 5 also comes out of the casting cylinder 3, and also comes out of the molten metal 1 and is positioned on the upper surface of the molten metal 1, after which the piston rod 6
etc. from the coupling ring 7, and remove it from the furnace (not shown).
Lower it from above.

Therefore, in this state, the piston ring 4 and the cast piston 5 can be easily replaced. After replacing these, attach the piston rod 6 etc. to the coupling 7 on the furnace, then switch the directional control valve of the hydraulic system 11 to the supply/discharge port 9.
When hydraulic pressure is applied to the pressurizing chamber 9a through d, the stroke adjusting piston 10 is lowered, and when the injection piston 8 is lowered, the casting piston 5 is automatically inserted into the casting cylinder 3 submerged in the molten metal 1. It moves back to the position shown in FIG. 1 where it is inserted. After that,
Returning to the normal state, the molten metal 1 is fed by the raising and lowering operation of the injection piston 8.

[Effects of the invention] As described above, according to the invention, the only work required on the furnace is replacing the piston ring or attaching and detaching the cast piston rod to the coupling ring, which improves workability and safety compared to conventional methods. performance is greatly improved.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a casting piston exchange device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing the operation mode of the exchange device shown in FIG. 1. 1... Molten metal, 3... Casting cylinder, 5... Casting piston, 6... Piston rod, 8... Injection piston, 9... Injection cylinder, 10... Stroke adjustment piston, 11... Hydraulic system.

Claims (1)

[Scope of utility model registration request] Hot chamber die casting in which a casting cylinder and a casting piston are disposed within the molten metal, and the casting piston is operated via a piston rod by an injection cylinder and an injection piston disposed outside the molten metal on a furnace. A casting piston changing device for a machine, which is an adjusting means comprising an adjusting piston disposed on an injection piston in an injection cylinder and having a flange, and a hydraulic device for regulating the vertical position of this adjusting piston in the injection cylinder. and
The adjusting means adjusts the operating stroke of the adjusting piston so that when replacing the casting piston and piston ring, the casting piston is raised to a position out of the gooseneck or to a position outside the molten metal in the furnace. A device for changing the casting piston in a hot chamber die casting machine.