JPH0619962U - Suction casting equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide a suction casting apparatus which has a small flow rate control valve to speed up the operation speed and enables fine movements, thereby improving control accuracy. [Structure] In a circuit 16 connecting a chamber 7 having a mold 6 inside and a vacuum pump 14, flow control valves 13a and 13b capable of varying exhaust flow rate are arranged in parallel, and each flow control valve 1
One control means 1 for simultaneously controlling the operation of 3a and 13b
It is configured by including 5.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a suction casting device.

[0002]

[Prior art and its problems]

 Conventionally, in a suction casting device, when exhausting with a vacuum pump to reduce the pressure inside an airtight container (pressure reducing chamber), a single flow rate control valve is provided and pressure reduction is performed by adjusting this flow rate control valve. However, since there is only one flow rate control valve, a large flow rate is required, and the operating speed is slow and it is difficult to perform fine movements, resulting in poor control accuracy.

[0003]

[Means for Solving the Problems]

 The present invention was devised in view of the above conventional problems, and an object thereof is not to provide a suction casting apparatus capable of improving control accuracy, and the gist thereof is to dispose a mold in an airtight container. Then, a suction casting apparatus for filling and casting the molten metal in the melting furnace or the molten metal holding furnace into the mold through the molten metal supply pipe by exhausting and depressurizing the inside of the container with a vacuum pump, the container and the vacuum pump Two or more flow control valves capable of changing the exhaust flow rate are arranged in parallel in the circuit connecting the two, and one control means for simultaneously controlling the operation of the two or more flow control valves is provided.

[0004]

[Action]

 Since two or more flow rate control valves are arranged in parallel in the circuit connecting the container and the vacuum pump, each flow rate control valve can be of a small flow rate, which increases the operating speed and Fine control is possible and the accuracy of exhaust control can be improved.

[0005]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a suction casting apparatus. A crucible 2 is arranged in a molten metal holding furnace 1, a molten metal 3 is put in the crucible 2, and the molten metal 3 is inside. A stalk (molten metal supply pipe) is provided above and below, and the upper end of the stalk 4 is communicated with a mold 6 arranged on a lower die base 5.

Further, an airtight chamber 7 is provided on the outer periphery of the mold 6, and a circuit 16 is connected to an exhaust port 8 of the chamber 7, and a valve 12 and a flow rate control are provided in the circuit 16. A valve 13a is provided and its tip is connected to the vacuum pump 14. Further, in this example, a bypass 17 is arranged in parallel in the circuit 16, and a flow control valve 13b is arranged in parallel with the flow control valve 13a in the circuit 17. An exhaust valve 11 is provided at the end of the branch circuit 18 branched from the circuit 16. The flow rate control valves 13a and 13b are electrically connected to the control means 15.

A circuit 19 is also connected to the pressure outlet 9 of the chamber 7, and a vacuum pressure sensor 10 is arranged in the circuit 19. The vacuum pressure sensor 10 is electrically connected to the control means 15. Connected to each other. When casting is performed in such an apparatus, the vacuum pump 14 is operated to evacuate the air inside the chamber 7 and decompress the inside of the chamber 7, so that the molten metal 3 is filled into the mold 6 through the stalk 4. It After the filling, the inside of the chamber 7 is further kept in a reduced pressure state, and the molten metal 3 is solidified in the mold 6.

Such a procedure is controlled by the control means 15, which receives the signal from the vacuum pressure sensor 10 to detect the pressure in the chamber 7, and based on this, stores it in the control means 15. The flow-rate control valves 13a and 13b are operated at the same time by performing a comparison calculation with the pressure-time pattern that has been performed and outputting an operation signal to the flow-rate control valves 13a and 13b to perform control along the pressure-time pattern. By operating the flow rate control valves 13a and 13b, the exhaust amount of the vacuum pump 14 is adjusted.

In this example, the flow rate control valves 13a and 13b can be made smaller, the operating speed can be made faster than before, and the small size enables fine operation. It is possible to improve the control accuracy as compared with the related art. In this example, two flow rate control valves 13a and 13b are arranged in parallel, but three or more flow rate control valves may be arranged in parallel, and one control means 15 can effectively control the flow rate control valves. Can be controlled.

[0010]

[Effect of device]

 According to the present invention, a mold is disposed in an airtight container, and the inside of the mold is evacuated by a vacuum pump to depressurize the molten metal in a melting furnace or a molten metal holding furnace through a molten metal supply pipe. In a suction casting device that fills and casts into a container, two or more flow control valves that can change the exhaust flow rate are arranged in parallel in the circuit that connects the container and the vacuum pump, and the two or more flow control valves are operated simultaneously. By having one control means for controlling, the flow rate control valve can be made to have a small flow rate to increase the operating speed, and fine operation is possible, which has the effect of improving control accuracy.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a suction casting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 molten metal holding furnace 2 crucible 3 metal molten metal 4 stalk (molten metal supply pipe) 6 mold 7 chamber 10 vacuum pressure sensor 13a, 13b flow control valve 14 vacuum pump 15 control means

Claims (1)

[Scope of utility model registration request] 1. A mold is disposed in an airtight container,
Regarding a suction casting apparatus for filling and casting a molten metal in a melting furnace or a molten metal holding furnace into the mold through a molten metal supply pipe by exhausting and decompressing the inside of the container with a vacuum pump, a circuit connecting the container and the vacuum pump Inside, two or more flow control valves that can change the exhaust flow rate are arranged in parallel.
A suction casting apparatus comprising one control means for simultaneously controlling the operation of two or more flow control valves.