JPH0195856A - Pump for supplying molten metal - Google Patents

Abstract

PURPOSE:To supply molten metal without communicating a melting furnace with a die, etc., by introducing the molten metal in a cylinder and supplying the molten metal in the cylinder into the die, etc., by pushing down the piston. CONSTITUTION:A pump 40 for supplying the molten metal is hung down with a crane and submerged into the molten metal 53 in the melting furnace 30. At the time of slowly ascending the piston 41 to the upper limit, the molten metal 53 in the melting furnace 30 is flowed into a bottom chamber 45 from an introducing hole 46 and filled up in the cylinder tube 42. Next, a suction valve 48 is descended to close the introducing hole 46 and the exhaust valve 52 is ascended to communicate a runner tube 35 with a stand-up tube 49. At the time of pushing down the piston 41 under this condition, the molten metal in the cylinder tube 42 is flowed to the stand-up tube 49 and sent to the runner tube 35 and supplied to the die 20. By this method, the construction is simplified and the control of the molten metal supplying quantity can be easily and surely executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hot water supply pump for molten metal, and more particularly to a hot water supply pump for molten metal suitable for filling a mold with molten metal by pressure operation.

[Conventional technology]

A hot water supply pump is used to supply molten metal such as aluminum to die casting machines such as vertical casting machines and horizontal casting machines, holding furnaces, and the like.

For example, JP-A-57-1 applied to a vertical low-pressure casting machine.
No. 19148, in which a furnace filled with molten metal and a mold are connected by a molten metal supply furnace, and an electromagnetic pump is installed in this molten metal supply furnace, and the electromagnetic pump pressurizes and fills the mold using the pressure inside the furnace. It is configured to be carried out by

However, with such a configuration, the method of adjusting and measuring the delivery speed or amount of molten metal becomes complicated;
Hot water supply cannot be controlled accurately. This problem similarly occurs when molten metal is sent to a closed melting furnace by air pressure, not by an electromagnetic pump.

As a solution to this problem, the present applicant previously proposed a hot water supply system shown in FIG.

In FIG. 5, the melting furnace I is filled with molten metal, and is of a non-crucible type. The melting furnace 1 is provided with a valve 2 for shutting off melting to the mold in an emergency, and this valve 2 is controlled by an air cylinder 3. Furthermore, a scene sensor 4 is installed in the melting furnace 1 to detect the level of the molten metal in the furnace.

A transfer furnace 5 is connected to the valve 2, and a pump device 6 for supplying hot water is connected to the other end as an incompressible molten metal transfer means.

The pump device f6 includes a plunger 7 that pumps the molten metal from the conveyance path 5 to the mold, a cylinder 8 that is fitted onto the plunger 7, a hydraulic cylinder 9 that reciprocates the plunger 7 within the outer cylinder 8, and It is comprised of a plunger pump system 10 that serves as a driving source for the hydraulic cylinder 9.

A runner pipe 11 is arranged with an inclination on the output side of the pump device 6, and a mold 20 is connected to the upper end of the runner pipe 11. A protective cover 12 made of a heat-resistant material such as ceramic is attached to the outer periphery of the runner 11 to prevent the temperature of the molten metal from decreasing, and a heat-retaining heater 13 is disposed within the cover 12.

The mold 20 consists of a fixed mold 21 and a movable mold 22,
A sprue 23 is arranged between the fixed mold 21 and the outlet of the runner pipe 11. - In the above configuration, the plunger pump system 10
is controlled using the control system shown in FIG. 2 according to a hot water supply program determined in advance according to the shape of the mold 20.

The plunger 7 in the initial state is on the rising side and communicates the conveyance path 5 with the runner 11.

Therefore, the runner 11 is filled with molten metal at the same height as the scene level in the melting furnace 1.

The plunger pump system 10 is driven with the movable mold 22 set in the fixed mold 21, and the plunger 7
When the plunger is lowered by a predetermined amount, the molten metal immediately below the plunger is pressed, and the level of the molten metal in the runner pipe 11 rises. This descent of the plunger 7 continues until the scene reaches the sprue 23.
It is done at high speed.

Next, the plunger 7 is lowered in stages to fill the cavity with molten metal according to the shape of the cavity.

After the mold 20 has been filled with molten metal, a constant high molten metal pressure is applied, and when the product has cooled down, the plunger 7 is raised to return the molten metal.

[Problem that the invention seeks to solve]

However, in the hot water pump having the configuration shown in Fig. 5,
A melting furnace without a crucible is required, and a general crucible furnace cannot be used. Further, although it is necessary to use ceramic or the like for the runner 11, there are problems in that it is difficult to increase the diameter and it is easily damaged. Furthermore, the level of the molten metal in the runner pipe fluctuates significantly along with the level of molten metal in the melting furnace, which may cause air to be trapped in the runner pipe, making it difficult to obtain a high-quality cast product.

The purpose of the present invention is to apply it regardless of the type of melting furnace. To provide a hot water supply pump for molten metal that is easy to manufacture and does not cause level fluctuations.

[Means for solving problems]

In order to solve the above problems, the present invention provides a piston that can be operated from outside the furnace, a cylinder tube in which the piston is arranged so as to be able to reciprocate, a predetermined space is formed at the lower end of the cylinder tube, and a molten metal inlet is provided. and a bottom flange provided with a molten metal discharge port, a suction valve that opens and closes the molten metal inlet in conjunction with the operation of the piston and communicates the bottom chamber with the melting furnace, and a suction valve connected to the molten metal discharge port and connected to the piston. A discharge valve mechanism is provided for communicating the bottom flange with an object to be supplied with molten metal such as a mold in conjunction with the operation of the melting furnace, and the melting furnace is immersed in the melting furnace to supply the melt.

[Effect]

Molten metal is introduced into the cylinder by opening the suction valve and pulling out the piston, and by closing the suction valve and opening the discharge valve and pushing down the piston, the molten metal in the cylinder is supplied to the mold, etc. Therefore, it is possible to configure a hot water supply pump that can supply hot water without communicating the melting furnace and the mold.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a sectional view of a hot water supply pump for molten metal and a mold for receiving hot water supply in one embodiment of the present invention.

In FIG. 1, the same mold as the mold 20 shown in FIG. 5 is used, so redundant explanation will be omitted.

A hot water supply pump 40 according to the present invention is disposed in the melting furnace 30 (or crucible) so as to be immersable therein, and is connected to the mold 20 by a flexible runner pipe 35 .

The hot water pump 40 has a piston 41 that can be operated from outside the furnace.
It is mainly composed of a cylinder tube 42 into which the piston 41 is fitted so as to be vertically movable. The cylinder tube 42 is supported by a top flange 43 and a bottom flange 44 by bolting. A bottom chamber 45 is formed in the bottom flange 44, and an inlet 46 is provided to enable communication between the bottom chamber 45 and the melting furnace 30. A valve seat 47 is formed in the introduction port 46, and a suction valve 48 whose tip shape matches the shape of the valve seat 47 is arranged so as to be able to open and close the introduction port 46. The upper part of the suction valve 48 is slidably supported by the top flange 43.

A riser pipe 49 is further connected to the bottom flange 44 so as to communicate with the bottom chamber 45, and a branch port 50 is provided at the upper part of the riser pipe 49 to which the runner pipe 35 is connected. riser pipe 4
The upper end of the pipe 9 is supported by the top flange 43, and a valve seat 51 is provided inside the pipe, and a discharge valve 52 for opening and closing the branch port 50 is inserted up to this position. The discharge valve 52, like the suction valve 48, can be raised and lowered from outside the furnace.

The hot water pump 40 configured as described above is immersed in the molten metal 53 in the melting furnace 30 while being suspended by a crane or the like.

Next, the operation of the configuration shown in FIG. 1 will be explained with reference to the operation diagrams shown in FIGS. 2 to 4.

First, as shown in FIG. 2, the suction valve 48 is at the upper limit;
The piston 41 is at the lower limit, and the discharge valve 52 is at the branch port 5.
0 is closed.

From this state, when the piston 41 is gradually raised to its upper limit as shown in FIG. .

Next, as shown in FIG. 4, the suction valve 48 is lowered to close the inlet 46, and the discharge valve 52 is raised to communicate the runner pipe 35 and the riser pipe 49. When the piston 41 is pressed down in this state, the molten metal in the cylinder tube 42 flows out to the riser pipe 49, is sent to the runner pipe 35, and is sent to the mold 20.
is supplied to

In this way, by providing the suction valve 48 and the discharge valve 52 and operating the piston 41, the riser pipe 49 can be kept filled with molten metal at all times. No phenomena occur.

Note that by using ceramic in the portion that comes into contact with the molten metal, heat retention and heat resistance can be improved.

〔Effect of the invention〕

As explained above, according to the present invention, since no electromagnetic pump or the like is used, the structure is simplified, and since the amount of hot water dispensed is proportional to the piston stroke, the amount of hot water dispensed can be easily and reliably controlled. , it becomes possible to reduce costs. Moreover, since it is an immersion type, it can be used in both a crucible furnace and a crucible-less furnace.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention, Figs. 2 to 4 are explanatory diagrams explaining the action of the hot water supply pump of the present invention, and Fig. 5 is a vertical low pressure using a conventional hot water supply system. It is a sectional view showing a casting machine. 20... Mold, 35... Water pipe, 40
...Hot water pump, 41...Piston,
42...Cylinder tube, 43...
Top flange, 44・Old bottom flange, 45・
...Bottom chamber, 46...Introduction port, 48.
...Suction valve, 49...Rise pipe, 50.
Old... Branch, 52... Discharge valve.

Claims (1)

[Claims] (1) A piston that can be operated from outside the furnace, a cylinder tube in which the piston is reciprocally arranged, and a bottom that forms a predetermined space at the lower end of the cylinder tube and is provided with a molten metal inlet and a molten metal outlet. a flange, a suction valve that opens and closes the molten metal inlet in conjunction with the operation of the piston and communicates the bottom chamber with the melting furnace; 1. A hot water supply pump for molten metal, characterized in that the pump is provided with a discharge valve mechanism that communicates the bottom scale with a target to be supplied with molten metal, and is immersed in the melting furnace to supply hot water.