JPH03258449A - Air pressurize molten metal supplying apparatus - Google Patents

Abstract

PURPOSE:To always keep molten metal supplying quantity into an injection sleeve the constant and to stably execute die casting operation by executing pressurization to molten metal surface in a molten metal dipping-out chamber connected to an injection sleeve with a molten metal supplying tube through expansion/shrinkage of bellows at the time of casting under pressurizing the molten metal into a die in a die casting machine. CONSTITUTION:The surface of molten metal 20 of Al alloy, etc., in a pressurizing chamber 31 is pressurized with pressurized air through a pressurizing air device 34, and after pushing up the molten metal into the dipping-out chamber 22 through communicating hole 32, a valve device 30 is pushed to the communicating hole 32 with an air cylinder 33 to shut off flowing of the molten Al alloy. Successively, the heat resistant alloy-made bellows 23 arranged at upper part of the dipping-out chamber 22 is shrunk with descent of a piston rod in a molten metal supplying cylinder 25, and the molten metal 20 in the dipping-out chamber 22 is supplied into the injection sleeve 15 through the molten metal supplying tube 20, and when the fixed quality of molten metal is supplied, by pushing up the injection plunger 16, the molten metal supplying hole 18 in the molten metal supplying tube 19 is shut off from the injection sleeve 15, and the molten Al alloy is cast into cavity 14 in the die under pressurizing. As the molten Al alloy supplying from the dipping-out chamber 22 is executed only with the expansion/ shrinkage of bellows 23 regardless of temp. of the pressurizing air, the molten Al alloy is always supplied into the injection sleeve 15 at the fixed quantity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Second Industrial Fields of Application] The present invention relates to a pneumatic pressurized hot water supply device that supplies hot water by pneumatically feeding molten metal to an injection sleeve of a pressurized IA manufacturing device such as a die casting machine.

BACKGROUND ART Conventionally, this type of pneumatic pressurized hot water supply apparatus as shown in FIG. 2 has been known, and this will be explained based on the drawings.

The figure shows an example of a water heater for a vertical die-casting machine.

11 is a fixed tie plate, 12 is a movable tie plate, 1
3 is a mold device, 14 is a cavity, 15 is an injection sleeve, 16 is an injection plunger, and 17 is an injection cylinder, which shows a part of the die-casting machine. 18 is the injection sleeve 151F at the hot water supply port! It opens in the l wall and connects the hot water supply pipe 19. 20 is a molten metal.

21 is a constant molten metal level holding furnace, a part of which is omitted.

Reference numeral 22 denotes a pumping chamber, which has an airtight structure, and has a communication port 32 at its bottom to communicate with the pressurizing chamber 31. 30 is a valve device provided to open and close the communication port 32. 33 is an actuator for opening and closing the valve device 3.0 using a pneumatic cylinder.

34 is a pressurized air device that supplies pressurized air to the pressurizing chamber 31 having an airtight structure, presses the molten metal in the pressurizing chamber 31, guides the molten metal to the pumping chamber 22 through the communication port 32, and The molten metal level is detected by a molten metal level sensor 35 and a detection signal is fed back to open and close the valve device 30 to control the molten metal level in the pumping chamber 22 to be constant.

40 is a pressurized air constant supply device which supplies pressurized air into the pumping chamber 22 for each casting cycle, closes the valve device 30, presses the molten metal in the pumping chamber 22, and connects the hot water supply pipe 19 and the hot water supply port 18. By the way, in such a conventional pneumatic pressurized hot water supply device, the pressurized air constant supply device 40 The temperature of the pressurized air supplied by the pump is at room temperature, while the air temperature inside the pumping chamber 22 is high temperature. room 2
2, it comes in contact with the high-temperature air in the pumping chamber 22 and is rapidly heated to a high temperature, resulting in engraving approximately 3.3 times the size, and the pressure in the pumping chamber 22 increases rapidly. Since the pressure fluctuates greatly, the amount of hot water supplied from the hot water supply pipe 19 fluctuates, causing a problem in that the accuracy of fixed hot water supply decreases.

Also, is it possible to eliminate pressure fluctuations in the pumping chamber due to temperature changes in the pressurized air by preheating room temperature pressurized air to almost the same high temperature as the pumping chamber before supplying it? The disadvantage is that it requires complicated equipment to heat and insulate the supply piping system.

The present invention has been made in view of the above-mentioned problems, and is a pneumatic system that improves the accuracy of quantitative hot water supply by essentially eliminating the cause of pressure fluctuations in the pumping chamber due to temperature changes in pressurized air during pressurized hot water supply. The purpose is to provide a pressurized water heater.

Means for Solving Two Problems] In order to achieve the above object, the present invention provides an airtight pressurized chamber that holds molten metal, and a communication port that connects the pressurized chamber to the pressurized chamber through a communication port provided with a valve device that is opened and closed by an actuator. an airtight pumping chamber that communicates with the pumping chamber; and a hot water level sensor that introduces pressurized air into the pressurizing chamber to press the molten metal and guide it to the pumping chamber through the communication port, and detects the surface of the molten metal in the pumping chamber. opening and closing the valve device in response to a signal to maintain the molten metal in the pumping chamber at a constant level;
In an air pressurized hot water supply device configured to press the held molten metal with pressurized air and supply hot water through a hot water supply pipe connected to a hot water supply port on the wall of an injection sleeve 1llI of a die-casting machine,
A pneumatic system characterized in that a bellows made of a heat-resistant alloy material is airtightly attached to the pumping chamber, and the volume of the upper space of the pumping chamber is varied to apply air pressure and supply a fixed amount of hot water to the injection sleeve of the die casting machine. It was a pressurized water heater.

Two functions: The volume of the upper space of the pumping chamber is changed by a bellows made of a heat-resistant alloy material that is airtightly installed in the pumping chamber, and when hot water is supplied under pressure, the bellows is compressed and the high-temperature air in the upper space of the pumping chamber is directly pumped. , the volume is reduced and the molten metal in the pumping chamber is pumped to supply a fixed amount to the injection sleeve of the die-casting machine.

Second Embodiment Hereinafter, an embodiment of the pneumatic pressurized water heater according to the present invention will be described.
A detailed description will be given based on the accompanying drawings.

For convenience of explanation, the same members as in the conventional pressurized pneumatic water heater shown in FIG. 2 are given the same reference numerals, and the explanation will be simplified.

FIG. 1 shows an embodiment of a water heater for a vertical die-casting machine. 11 is a fixed tie plate, 12 is a movable tie plate, 13 is a mold device, 14 is a cavity, 15 is an injection sleeve, 16 is an injection plunger, 17 is an injection cylinder,
1 illustrates a portion of a die casting machine. Reference numeral 18 denotes a hot water supply port, which opens in the side wall of the injection sleeve 15 and connects a hot water supply pipe 19 thereto. 20 is a molten metal, and 621 is a constant molten metal level holding furnace, some of which are omitted from the illustration.

22 is a pumping chamber, and 23 is a bellows made of a heat-resistant metal material.
4 to shape the upper space of the pumping chamber 22 as an airtight structure, and the piston rod 26 of the hot water supply sill 25 is attached to the push plate 24, so that the volume of the upper space can be varied by expanding and contracting the bellows 23. It is supposed to be done.

The hot water supply cylinder 25 is fixed to a frame 27 fixed to the earthen wall of the furnace. The frame 27 is definitely surrounded by a board,
The outside of the bellows 23 may be kept warm.

Reference numeral 28 denotes a position sensor for the hot water supply cylinder, which is a potentiometer or the like, and is designed to detect the stroke of the hot water supply cylinder and obtain a water supply completion signal for quantitative hot water supply.

Reference numeral 29 is a solenoid valve that is controlled to close when a hot water supply start signal is received and to open when a hot water supply completion signal is received.

A valve device 30 is provided on the bottom of the pumping chamber 22 and opens and closes a communication port 32 with the pressurizing chamber 31.

33 is a pneumatic syringe and is an actuator of the valve device 30.

34 is a pressurized air device that supplies the pressurized chamber 31;
1 is pressed to supply the molten metal to the pumping chamber 22 through the communication port 32, and the signal from the molten metal level sensor 35 that detects the molten metal surface in the pumping chamber 22 is fed back to keep the molten metal in the pumping chamber 22 at a constant level. The valve device 30 is closed when the pumping chamber 22 reaches a constant level.

Next, the operation of the pneumatic water heater of the present invention will be explained.

Keeping the hot water level in the pumping chamber 22 constant and closing the valve device 30,
The hot water supply cylinder 25 operates with the hot water supply start signal, and the bellows 2
3 to reduce the volume of the upper space of the pumping chamber 22, and increase the pressure in the pumping chamber 22 to forcefully feed the molten metal 20,
Molten metal is supplied to the injection sleeve 15 from the hot water supply port 18 via the hot water supply port 9 . The forward movement of the hot water supply cylinder 25 is stopped in response to a hot water supply completion signal from a hot water supply control panel having a timer (not shown) or a hot water supply completion signal detected by the position sensor 28 of the hot water supply cylinder 25 to detect the stroke of the piston rod 26 of the hot water supply cylinder 25. At the same time, the injection plunger 16 is moved forward to close the hot water supply port 18 and completely cut off the supply of molten metal.

The injection plunger 16 is detected by the limit switch 36 and the injection plunger stroke detection means by the dog 37.
After confirming that the hot water supply port 18 is completely closed, a signal is sent, and in response to this signal, the hot water cylinder 25 is moved back, the volume in the drawing chamber 22 is filled, the pressure in the same chamber is reduced, and the hot water supply port 18 is closed. The molten metal in the vicinity of No. 18 is made to flow back into the pumping chamber No. 22 to empty it (to ensure that the hot water drains well).

Then, the solenoid valve 29 is opened to release the pressure inside the pumping chamber 22 to the atmosphere.

Since the volume of the high-temperature air in the upper space of the pumping chamber 22 is compressed in this way, stable pneumatic pressurized hot water supply is possible, and it is easily possible to maintain the quantitative accuracy of the hot water supply amount.

The present invention is not limited to vertical injection pressure casting machines such as vertical die casting machines, but can also be applied to horizontal injection pressure casting machines such as horizontal die casting machines.

[Effects of the Invention] As described above, the pressure inside the pumping chamber is controlled by the pneumatic pressurizing means that changes the volume of the upper space of the pumping chamber to supply hot water under pneumatic pressure. It is possible to essentially eliminate the cause of pressure fluctuations caused by sudden changes in temperature of pressurized air at room temperature, and this has the effect of improving the accuracy of quantitative hot water supply.

Furthermore, since pressurized air is not introduced from the outside, equipment for heating and insulating the pressurized air supply piping system is not required.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a pneumatic pressurized water heater showing an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional pneumatic pressurized water heater. 11... Fixed tie plate, 12... Movable tie plate, 13... Mold device, 1
5... Injection sleeve, 16... Injection plunger, 1
7... Injection cylinder, 18... Hot water supply port, 19...
Hot water supply pipe, 20... Molten metal, 21... Constant molten metal level holding furnace, 22... Pumping chamber, 23...
・Bellows, 24... Push plate, 25... Hot water cylinder, 26... Piston rod, 27... Frame, 2
8...Position sensor, 29...Renoid valve,

Claims (1)

[Claims] an airtight pressurized chamber that holds the molten metal; an airtight pumping chamber that communicates with the pressurized chamber through a communication port provided with a valve device that is opened and closed by an actuator; and pressurized air is introduced into the pressurized chamber and the molten metal is is pressed to guide the molten metal into the drawing chamber through the communication port, and the molten metal in the drawing chamber is maintained at a constant level by opening and closing the valve device in response to a signal from a molten metal level sensor that detects the molten metal level in the drawing chamber. , a pneumatic pressurized hot water supply device configured to press the held molten metal with pressurized air and supply hot water through a hot water supply pipe connected to a hot water supply port on a side wall of an injection sleeve of a die casting machine, in which a heat-resistant alloy material is placed in the pumping chamber. A pneumatic pressurized hot water supply device, characterized in that a bellows is airtightly attached, and the volume of the upper space of the pumping chamber is varied to apply pneumatic pressure and supply a fixed amount of hot water to the injection sleeve of the die casting machine.