JP2000117417A - Molten metal supplying pump device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a stable supply of the constant quantity of molten metal into an injection sleeve without deteriorating the quality of the molten metal caused by the surface oxidation and the surface combustion and to enable the improvement of molten metal supplying efficiency. SOLUTION: In a molten metal supplying pump device, a pump sleeve 2 disposed by dipping in the molten metal M in a closed heat-insulating furnace 7, a plunger 3 fitted in this pump sleeve 2 so that the lower end part 3a is vertically movable and also, disposed by connecting the upper end part 3b with an air cylinder 9, a stopper means 4 regulating the lower limit position of the plunger 3, molten metal supplying piping 5 connecting a spouting hole 2a in the pump sleeve 2 with a molten metal supplying hole 8a in the injection sleeve 8 and a check valve 6 disposed in the intermediate part of this molten metal supplying piping 5 and holding the surface B of the molten metal M in the piping 5 by approaching the molten metal supplying hole 8a in the injection sleeve 8, are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pump for supplying molten metal to an injection sleeve of a die casting machine.

[0002]

2. Description of the Related Art Generally, a hot water supply apparatus for supplying molten metal to an injection sleeve of a die casting machine is a ladle hot water supply system in which molten metal is drawn from an insulated furnace storing molten metal by an automatic machine using a ladle and is poured into the injection sleeve. Either an electromagnetic pump system that supplies water with an electromagnetic pump or a plunger-type hot water supply pump system that uses a plunger-type hot water supply pump to supply hot water to the injection sleeve based on the surface of the molten metal in the insulated furnace.

[0003]

However, the ladle hot water supply method has a problem that air entrapment is inevitable when pouring air into the injection sleeve with the ladle, thereby causing surface oxidation and surface combustion of the molten metal. are doing.

The electromagnetic pump system can solve the above-mentioned problem of the ladle hot water supply system because the molten metal is transported to the injection sleeve via a pipe, but the electromagnetic characteristics of the molten metal determine the amount of the molten metal. Since the amount of molten metal is controlled by time, and the amount of supplied hot water varies due to a change in passage resistance, there is a problem that it is difficult to stably supply a constant amount of hot water to the injection sleeve.

Further, the plunger type hot water supply pump system is
Since the molten metal surface in the insulated furnace is used as the basis for calculating the amount of hot water supplied, there is a difference between the height of the inlet of the injection sleeve and the reference metal surface height, and the amount of molten metal corresponding to the difference is the amount of molten metal in the injection sleeve. Therefore, there is a problem that it is necessary to prepare a large amount of hot water including waste, which leads to a decrease in hot water supply efficiency.

Therefore, the present invention enables stable and constant hot water supply to the injection sleeve without deteriorating the quality of the molten metal due to surface oxidation or surface combustion, and also improves the hot water supply efficiency at that time. It is an object of the present invention to provide a molten metal hot water supply pump device.

[0007]

In order to achieve the above object, a first aspect of the present invention is a pump which is immersed and installed in a molten metal of a closed insulated furnace into which a gas for oxidizing the molten metal is injected. A sleeve, a plunger whose lower end is vertically movably fitted to the pump sleeve and whose upper end is connected to driving means installed outside the closed insulated furnace, and a plunger installed outside the closed insulated furnace. Stopper means for regulating a lower limit position of the plunger, a molten metal supply pipe connecting the discharge port of the pump sleeve and a hot water supply port of the injection sleeve, and injecting an oxidation-resistant gas of the molten metal into an internal space, and a molten metal supply pipe A check valve installed at an intermediate portion of the pipe to maintain the level of the molten metal in the pipe close to the hot water supply port.

According to the first aspect of the present invention, the molten metal is supplied to the injection sleeve from the discharge port of the pump sleeve via the molten metal supply pipe by the downward movement of the plunger by the driving means. The lowering of the plunger is stopped at the lower limit position by the stopper means, and the hot water supply ends. After this hot water supply,
The plunger is moved upward by the driving of the driving means, and stops at the upper limit position of the driving means. The stroke of the plunger at this time is kept constant by the stopper means.

The molten metal in the molten metal supply pipe is held in the pipe by bringing the surface of the molten metal close to the hot water supply port of the injection sleeve without returning to the pump sleeve even when the plunger is moved upward by the check valve. Thereby, at the time of hot water supply, almost the entire amount of molten metal of the stroke of the plunger can be supplied to the injection sleeve.

According to a second aspect of the present invention, there is provided the molten metal hot water supply pump device according to the first aspect, wherein the plunger has a plunger guide having an intermediate portion provided above a furnace lid of the closed heat insulating furnace. It is characterized by being installed so as to be vertically movable.

According to the second aspect of the present invention, since the plunger can sufficiently increase the support interval during a stroke by the pump sleeve and the plunger guide,
Even if the fitting length of the lower end portion to the pump sleeve is shortened, a smooth movement at the time of a stroke can be ensured.

According to a third aspect of the present invention, there is provided the molten metal hot water supply pump device according to the second aspect, wherein the stopper means comprises:
A stopper receiver detachably attached to an intermediate position between the driving means and the plunger guide, a stopper attached to the stopper receiver so as to be capable of adjusting a position in a vertical direction, and the driving means and the plunger being detachable. And a step portion provided on the connecting bar to be connected and abutting against the stopper when the plunger moves downward to regulate a lower limit position of the plunger.

For this reason, in the invention of claim 3, the stroke amount of the plunger is determined by the amount from the upper limit position of the driving means to the lower limit position where the step of the connecting bar abuts against the stopper.

Further, since the stopper means is set at an intermediate position between the driving means and the plunger guide, it is possible to easily adjust the position of the stopper while preventing the set position from being high.

[0015] The invention of claim 4 is the invention of claims 1 to 3
The molten metal hot water supply pump device according to any one of the above,
The molten metal supply pipe has an upper vertical pipe part whose upper part protrudes upward from the furnace lid of the closed heat insulating furnace and communicates with a hot water supply port of the injection sleeve, and whose lower part is immersed in the molten metal of the closed heat insulating furnace and opened. A portion in which an upper portion is opened to face a lower portion of the upper vertical tube portion and a lower portion is communicated with a discharge port of the pump sleeve, and a lower vertical tube portion is opened by pressing the upper vertical tube portion downward. The check valves are configured so as to be detachable from each other, and the check valve is configured by arranging a poppet in a pipe at the tapered fitting portion.

For this reason, in the invention of claim 4, the check valve is
Since it is installed immersed in the molten metal of the closed insulated furnace, no oxide is generated at the check valve.

Further, the check valve can be disassembled by releasing the downward pressing force acting on the upper vertical pipe to release the upper vertical pipe from the lower vertical pipe. Can perform maintenance.

Further, since the molten metal supply pipe is assembled by taper fitting by pressing both open portions of the upper vertical pipe section and the lower vertical pipe section, the upper vertical pipe section and the lower vertical pipe section are simultaneously assembled. Can be aligned.

[0019]

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

FIG. 1 shows a molten metal hot water supply pump device 1 as one embodiment of the present invention. This hot water supply pump device 1
Is a pump sleeve 2 which is immersed and installed in the molten metal M of a sealed insulated furnace 7 into which an oxidation-resistant gas G of the molten metal M is injected, and a lower end portion 3a of the pump sleeve 2 is vertically movably fitted. At the same time, a plunger 3 whose upper end 3b is connected to an air cylinder 9 as a driving means installed outside the closed heat insulating furnace 7 and a stopper installed outside the closed heat insulating furnace 7 and controls the lower limit position of the plunger 3 A means 4 for connecting a discharge port 2a of the pump sleeve 2 to a hot water supply port 8a of the injection sleeve 8 and injecting an oxidation-resistant gas G of the molten metal M into an internal space; A check valve 6 is provided at an intermediate portion, and has a check valve 6 for maintaining the surface B of the molten metal M in the pipe 5 close to the hot water supply port 8 a of the injection sleeve 8.

The reason why the air cylinder 9 is used as the driving means is to avoid troubles caused by a fire danger caused by oil leakage or the like in consideration of the case where the molten metal M is a magnesium alloy.

The closed insulated furnace 7 has an upper opening portion covered with a furnace lid 11, the molten metal M is stored therein, and the acid-resistant material of the molten metal M is formed in a space between the furnace lid 11 and the molten metal surface A. It is configured by injecting a forming gas G. For this reason, the furnace lid 11
A gas injection valve 29 for injecting the oxidation resistant gas G is provided.

The pump sleeve 2 has a bottomed cylindrical shape with an open top, a flange portion 2c formed at the outer periphery of the upper end, a suction port 2b formed at the top of the side wall, and a discharge port 2a formed at the bottom wall.
The flange portion 2c and the furnace lid 1
1 is connected to a frame 31 provided with the opening 1 and is immersed in the molten metal M and installed.

The lower end 3 a of the plunger 3 is fitted to the pump sleeve 2 so as to be vertically movable, and the upper end 3 b pulled out above the furnace lid 11 is connected to the cylinder of the air cylinder 9 via a connecting bar 15. It is installed by being connected to a cylinder rod joint shaft 17 screwed to the rod. The air cylinder 9 is attached to the top of the pump frame 10 erected on the frame 31 with the cylinder rod joint shaft 17 facing downward.

FIG. 2 shows a connection structure between the connection bar 15 and the cylinder rod connecting shaft 17. That is, a large-diameter head 16 is formed on the upper part of the connecting bar 15,
A stepped engagement recess 16 </ b> A is formed in the head 16 so as to open to the upper end surface and side surfaces of the head 16. The stepped engagement recess 16A is formed in the radial direction by vertically connecting the lower wide engagement recess 16b and the upper narrow engagement recess 16c. The lower surface of the head 16 is a step 16a that constitutes the stopper means 4, and a peripheral step 16d is formed in the middle of the outer periphery of the head 16.

On the other hand, at the lower part of the cylinder rod joint shaft 17, a stepped shaft portion 17A engaged with the stepped engagement recess 16A is provided.
Are formed. The stepped shaft portion 17A has a diameter substantially equal to the width of the narrow engagement recess 16c, and has a small diameter shaft portion 17b protruding from the lower end surface of the cylinder rod joint shaft 17 and a width of the wide engagement recess 16b. And a large-diameter shaft portion 17a formed below the small-diameter shaft portion 17b. A collar 18 is externally attached to the cylinder rod joint shaft 17 so as to be vertically movable.

The connecting bar 15 and the cylinder rod connecting shaft 17 are connected to the wide engaging recess 16 of the stepped engaging recess 16A.
b and the narrow engaging concave portion 16c
A, the large-diameter shaft portion 17a and the small-diameter shaft portion 17b are fitted, and the collar 18 is moved downward so that the peripheral step portion 16d of the connecting bar 15 is moved.
And the fitting portion is surrounded by the collar 18, whereby the stepped engagement recess 16A and the stepped shaft portion 17A are prevented from separating from each other and connected. In such a connection structure, the connection bar 15 and the cylinder rod connecting shaft 17 are moved upward by the collar 18 to release the surrounding of the fitting portion, so that the stepped engagement concave portion 16A and the stepped shaft portion 1 are released.
7A can be separated from each other, and thereby can be easily separated.

The connecting bar 15 and the plunger 3 also
They are connected by the same connection structure as described above. Therefore, the connection bar 15 is detachably connected between the cylinder rod joint shaft 17 of the air cylinder 9 and the plunger 3. The through-hole 15a provided at an intermediate portion of the connection bar 15 supports the collar on the plunger 3 side by a pin (not shown) inserted through the through-hole 15a at a position where the collar has been moved upward when the connection is released. It is for.

In the present embodiment, the plunger 3 is installed so that its intermediate portion is vertically movable and supported by a plunger guide 12 provided above the furnace lid 11 of the closed heat insulating furnace 7. Specifically, as shown in FIG. 1, the plunger guide 12 has a substantially cylindrical shape with a bottom as a whole, and has a guide hole 12a formed in the bottom. The plunger guide 12 has an opening facing downward so that the bottom is upward, and the opening communicates with the opening of the frame 31 so that the guide hole 12 a is positioned concentrically with the pump sleeve 2. It is positioned and attached to the frame 31. At this time, the plunger guide 12 is detachably attached to the frame 3 in consideration of maintenance.
Attach to 1. Pins (not shown) are inserted into the plunger 3 at the time of maintenance, and the pins are brought into contact with the upper surface of the plunger guide 12 to support the plunger 3 at a desired height. It is drilled in.

The plunger 3 has a guide hole 1 at an intermediate portion thereof.
The lower end 3a is guided by the pump sleeve 2 while being guided by the pump sleeve 2 so as to be vertically movable.

According to the supporting structure of the plunger 3, the plunger 3 is composed of the pump sleeve 2 and the plunger guide 1.
2, the support interval at the time of a stroke can be made sufficiently long. Therefore, even if the fitting length of the lower end portion 3a to the pump sleeve 2 is shortened, the plunger 3 can smoothly move without slack at the time of the stroke. be able to. Therefore, by shortening the fitting length of the lower end 3a of the plunger 3 to the pump sleeve 2, the weight of the plunger 3 can be reduced.
And the pump body (the periphery of the pump sleeve 2) can be made compact, and the plunger 3
And the heat capacity of the plunger 3 can be reduced, and the amount of drop in the temperature of the molten metal when the plunger 3 is placed in the molten metal M can be reduced.

In addition, since the supporting interval of the plunger 3 can be made sufficiently long, the molten metal attached to the plunger 3 during the stroke can be prevented from reaching the plunger guide 12, thereby guiding the guide hole 12a. Functions can be sufficiently secured.

The stopper means 4 is provided outside the closed heat-retaining furnace 7. In the present embodiment, as shown in FIG. 1, the stopper means 4 includes a stopper receiver 13 detachably mounted at an intermediate position between the air cylinder 9 and the plunger guide 12, and a vertical position adjustment on the stopper receiver 13. The connecting bar 1 for detachably connecting the stopper 14, which is detachably attached, and the air cylinder 9 and the plunger 3.
5, a step 16a that abuts against the stopper 14 when the plunger 3 moves downward and regulates the lower limit position of the plunger 3.
It is composed of

The stopper receiver 13 is formed of a rectangular plate having a screw hole having a diameter sufficiently larger than the outer diameter of the plunger 3 at the center, and an intermediate position between the air cylinder 9 and the plunger guide 12. Pump frame 10 corresponding to
Stopper dies 10 formed on both sides of the intermediate portion
The two side portions are fixed to and supported by the position bars 13a, 13a. This stopper receiver 13 is
By pulling out the position bars 13a, 13a, they can be easily detached from the stopper dies 10a, 10a,
In addition, by rotating 90 ° horizontally from the fixed position, it is possible to move up and down along the plunger 3 while avoiding interference with the stopper dies 10a, 10a.

The stopper 14 has a stopper receiver 13 on its outer periphery.
A screw thread to be screwed into the screw hole is engraved, and is formed of a cylindrical body having an inner diameter substantially equal to the outer diameter of the plunger 3, and a connecting body between the connecting bar 15 and the plunger 3 is provided inside. It is inserted and screwed into the screw hole of the stopper receiver 13. For this reason, the stopper 14 can be adjusted in the vertical direction by rotating about the axis, so that the stopper 14 is positioned above the stopper receiver 13 and can be fixed in position by the nut 19 screwed to the stopper 14. Has become.

The step 16a is connected to the connecting bar 1 as described above.
5 is formed as a lower surface of the head 16 (see FIG. 2), and is located above the connecting bar 15 through which the stopper 14 is inserted.

According to the stopper means 4 configured as described above, the stroke amount S of the plunger 3 is an amount from the upper limit position of the air cylinder 9 to the lower limit position where the step 16a of the connecting bar 15 abuts against the stopper 14. Thus, the stroke amount S of the plunger 3 can be accurately set. The stroke amount S at this time can be steplessly adjusted by adjusting the screw of the screw portion of the stopper 14.

Further, since the stopper means 4 is set at an intermediate position between the air cylinder 9 and the plunger guide 12, it is possible to easily adjust the position of the stopper 14 while preventing the set position from being high. Therefore, workability can be improved.

The molten metal supply pipe 5 is provided so as to communicate the pump sleeve 2 and the injection sleeve 8, and the check valve 6 is provided at an intermediate portion of the molten metal supply pipe 5.

In the present embodiment, the molten metal supply pipe 5 has an upper part projecting upward from the furnace lid 11 of the closed heat insulating furnace 7 to communicate with the hot water supply port 8 a of the injection sleeve 8 and a lower part inside the molten metal M of the closed heat insulating furnace 7. Vertical pipe section 20 which is immersed and opened in
And a lower vertical tube portion 21 whose upper portion is opened facing the lower portion of the upper vertical tube portion 20 and whose lower portion communicates with the discharge port 2a of the pump sleeve 2 is opened by pressing the upper vertical tube portion 20 downward. The tapered portions are detachably taperedly fitted to each other. The check valve 6 has a poppet 2 in a pipe at a portion where the upper vertical pipe 20 and the lower vertical pipe 21 are tapered.
2 are arranged.

More specifically, as shown in FIG. 1, the upper portion of the upper vertical tube portion 20 is pulled out of the furnace upward from a pipe guide 40 provided on a frame 31 covering the opening of the furnace lid 11. It communicates with the molten metal pipe 26 bent in an L shape,
The vertical pipe of the molten metal pipe 26 is connected to an inclined pipe 27, and the inclined pipe 27 is connected to a vertical discharge pipe 28 connected to a hot water supply port 8a of the injection sleeve 8. It is formed in a large-diameter portion having a large pipe inner diameter, and a lower inner peripheral surface of the large-diameter portion is formed in a tapered surface 20a. It is installed immersed in. A heater 41 is provided on the outer peripheral portion of the upper vertical pipe portion 20 up to the inclined pipe 27 disposed above the molten metal surface A. A gas injection valve 30 for injecting the oxidation resistant gas G into the space of the molten metal pipe 26 is provided at an upper opening of the vertical pipe of the molten metal pipe 26. In addition, the lower end of the discharge pipe 28 and the hot water supply port 8a are not brought into close contact (push contact) in consideration of movement, heat influence, and the like, and the oxidation-resistant gas G injected from the gas injection valve 30 is invisible. Install the unit close enough to prevent diffusion.

The other lower vertical tube portion 21 has an opening on one side whose outer peripheral surface has a tapered surface 2 corresponding to the tapered surface 20a.
1a, the inner peripheral surface is formed to be a tapered surface 21b which functions as a seat of the poppet 22, and the other side is connected to the pump sleeve 2 via a molten metal path 35.
And is entirely immersed in the molten metal M.

The molten metal supply pipe 5 is connected to the upper vertical pipe section 2.
0 and the lower vertical tube portion 21 are taperedly fitted to each other by pressing the upper vertical tube portion 20 downward, and the pressing mechanism at this time is as follows.

That is, the pressing mechanism is a pump frame 10
And a heat insulating piece 23 interposed between the pipe pressing tool 24 and the upper end of the vertical portion of the upper vertical pipe section 20. Have been. The pipe pusher 24 has a nut 24
a is screwed, and by pressing down the nut 24 a, the upper vertical pipe portion 20 can be pressed downward through the heat insulating piece 23.

The molten metal supply pipe 5 presses the upper vertical pipe section 20 downward by the pressing mechanism, so that the tapered surface 20 is pressed.
The upper vertical pipe 20 and the lower vertical pipe 21 are connected by taper fitting of the upper and lower pipes 21a and 21a. Since this taper fitting is performed while picking up the cores of the tapered surfaces 20a and 21a, the upper vertical tube 20 and the lower vertical tube 21 can be simultaneously aligned.

The check valve 6 is provided by mounting the poppet 22 on the tapered surface 21b at the upper open end of the lower vertical pipe portion 21 so as to close the pipe line.
It is configured at the large diameter portion at the lower end of the zero. Thereby, the check valve 6
The poppet 22 closes the conduit of the lower vertical pipe portion 21 by its own weight, and the surface B of the molten metal M in the molten metal supply pipe 5 can be kept close to the hot water supply port 8 a of the injection sleeve 8. Specifically, the molten metal surface B in the molten metal supply pipe 5 is
It is maintained at the communication portion of the zero inclined pipe 27.

Since the check valve 6 is immersed in the molten metal M of the closed heat-retaining furnace 7, no oxide is generated in the check valve 6.

Further, the check valve 6 releases the downward pressing force acting on the upper vertical pipe section 20 to release the upper vertical pipe section 2.
0 can be disassembled by detaching it from the lower vertical tube portion 21, and maintenance can be performed by this disassembly.

The molten metal hot water supply pump device 1 configured as described above operates as follows.

The state shown by the solid line in FIG. 1 shows the state before hot water supply. That is, the cylinder rod joint shaft 17 is located at the upper limit position of the air cylinder 9, whereby the lower end 3 a of the plunger 3 is located above the pump sleeve 2 that opens the suction port 2 b. Then, the molten metal M in the closed insulated furnace 7 flows from the suction port 2b and flows into the pump sleeve 2b.
And the lower vertical tube portion 21 and the upper vertical tube portion 2
The inside of the molten metal supply pipe 5 is filled so that the molten metal surface B comes to the communication part of the 0 inclined pipe 27. In addition, the inclined pipe 27 and the discharge pipe 2 extend from the surface B of the molten metal pipe 26 of the molten metal supply pipe 5.
8 and the gap in the tube leading to the injection sleeve 8 are filled with the oxidation-resistant gas G injected from the gas injection valve 30.

When the air cylinder 9 is driven in this state, the plunger 3 moves down until the step 16a of the connecting bar 15 abuts against the stopper 14, whereby the lower end 3a of the plunger 3 in the pump sleeve 2 moves the stroke amount. S
Only move down. Due to the downward movement of the lower end 3 a of the plunger 3, the molten metal M filled in the pump sleeve 2 and the molten metal supply pipe 5 flows while pushing up the poppet 22 of the check valve 6, and the discharged molten metal corresponding to the stroke amount S is discharged. Is supplied to the injection sleeve 8 from the hot water supply port 8a via the inclined pipe 27 and the discharge pipe 28.

When the supply of the molten metal M to the injection sleeve 8 is completed, the plunger 3 is moved upward by the air cylinder 9 to the upper limit position of the air cylinder 9. At this time, the molten metal M in the molten metal supply pipe 5 does not return to the pump sleeve 2 even when the plunger 3 is moved upward by the check valve 6, and the molten metal surface B
Is brought close to the hot water supply port 8a of the injection sleeve 8 and is held in the pipe. This eliminates the movement of the discharge-side molten metal when the plunger 3 is moved upward, thereby eliminating the entrainment of air due to the movement of the discharge-side molten metal.

As described above, in the molten metal feed pump device 1, the molten metal M is supplied to the injection sleeve 8 through the molten metal supply pipe 5.
Molten metal M by surface oxidation or surface combustion
Since the quality of the plunger 3 is not deteriorated and the stroke amount S of the plunger 3 is kept constant by the stopper means 4 (stopper 14), stable fixed-quantity hot water supply to the injection sleeve 8 is possible. Hot water supply port 8
Since the molten metal surface B is approached from a, the discharged molten metal for the stroke amount S is supplied to the injection sleeve 8, so that an unnecessary amount of hot water is not required, thereby improving the hot water supply efficiency. did.

In addition, the closed heat-retaining furnace 7 is repeatedly operated and stopped, and accordingly, the molten metal M in the furnace is repeatedly melted and solidified. At this time, if the plunger 3 is left assembled to the pump sleeve 2, since these are made of a metal material, they do not break or break, but they are deformed, and the plunger 3 cannot move smoothly. For this reason, when the operation is stopped, the plunger 3 is removed from the molten metal M, and when the operation is performed, the plunger 3 is inserted into the pump sleeve 2 again. In the present embodiment, this operation is performed as follows.

That is, when the closed heat insulating furnace 7 is stopped, a pin is inserted into the through hole 15b at the upper limit position of the air cylinder 9 and the pin is brought into contact with the upper surface of the plunger guide 12 to stop the downward movement of the plunger 3. After that, the stopper receiver 13 together with the stopper 14 is removed from the stopper die 10a and placed on the upper surface of the plunger guide 12. Thereafter, the connecting bar 15 is connected to the cylinder rod 17 and the plunger 3.
Then, the stopper receiver 13 is removed together with the stopper 14 from the system using the space between the cylinder rod 17 and the plunger 3. Thereafter, the plunger 3 is manually moved upward, a pin is inserted into the through hole 15c, and this pin is brought into contact with the upper surface of the plunger guide 12, and
The state in which the lower end 3a of the plunger 3 has come off from the molten metal M is maintained.

When the furnace temperature is lowered in this state, the molten metal M becomes
It solidifies below its freezing point. During this time, since the oxidation-resistant gas G is in the injected state, there is no oxidation of the molten metal M attached to the surface of the plunger 3.

When the furnace is operated again, the temperature of the closed heat-retaining furnace 7 is raised to melt the molten metal M, the pin of the through hole 15c is removed, and the plunger 3 is moved downward. And the pin of the through hole 15b is brought into contact with the upper surface of the plunger guide 12 to stop the plunger 3 from moving further downward. Then, the stopper 1
4 is inserted through the plunger 3, the stopper receiver 13 is placed on the upper surface of the plunger guide 12, the connecting bar 15 is connected between the cylinder rod joint shaft 17 and the plunger 3, and the stopper receiver 13 is connected to the stopper die 10a. Attachment is completed by removing the pin of the through hole 15b, and the operation of the molten metal feed pump 1 can be restarted. In the operation of the molten metal feed pump 1 at this time, the plunger 3 can be driven with the same stroke amount S as the previous operation because the height position of the stopper 14 is maintained as it was during the previous operation.

Further, since the check valve 6 is immersed in the molten metal M and is installed therein, no oxide is generated there. However, since the molten metal M is easily oxidized, oxides and the like are repeatedly subjected to repeated operations. The contamination may reach the check valve 6. In this case, since a sheet failure or the like occurs, maintenance such as repair of the check valve 6 is required. This maintenance is performed by separating the upper vertical pipe portion 20 and the lower vertical pipe portion 21 of the molten metal supply pipe 5. Can be performed more easily.

[0059]

As described above, according to the first aspect of the present invention, the molten metal is conveyed to the injection sleeve via the molten metal supply pipe, so that quality deterioration of the molten metal due to surface oxidation and surface combustion can be prevented. Since the amount of plunger stroke is kept constant by the stopper means without any accompanying, stable hot water supply to the injection sleeve is possible and a check valve is provided in the middle of the molten metal supply pipe. Since the hot water is supplied from the surface of the pipe close to the hot water supply port at that time, the discharge molten metal corresponding to the stroke amount is supplied to the injection sleeve, so that an extra hot water supply amount is not required, and as a result, hot water is supplied. A molten metal hot-water supply pump device that can also improve the efficiency can be provided.

Further, according to the second aspect of the present invention, a smooth movement during a stroke can be ensured even if the fitting length of the lower end of the plunger to the pump sleeve is shortened. By shortening the length, in addition to the effect of the first aspect of the invention, the weight of the plunger and the size of the pump body can be reduced, and
The heat capacity of the plunger is reduced, so that the amount of drop in the temperature of the molten metal when the plunger is put into the molten metal can be reduced, and the handling of the plunger becomes easier.

In addition, by making the plunger support interval sufficiently long, it is possible to prevent the molten metal adhering to the plunger during the stroke from reaching the plunger guide, thereby ensuring a sufficient guide function of the guide hole. be able to.

According to the third aspect of the present invention, the amount of stroke of the plunger is determined by the amount from the upper limit position of the drive means to the lower limit position where the step of the connecting bar abuts against the stopper. In addition to the effects of the second invention,
The stroke amount of the plunger can be set with high accuracy.

In addition, since the stopper means is set at an intermediate position between the driving means and the plunger guide, it is possible to easily adjust the position of the stopper while preventing the set position from being high. Thereby, workability can be improved.

According to the fourth aspect of the present invention, the check valve is immersed and installed in the molten metal of the closed insulated furnace, so that the check valve is provided in addition to the effect of the first aspect of the present invention. hand,
Oxide generation at the check valve can be prevented.

In addition, the molten metal supply pipe is assembled by taper fitting by pressing the open portions of both the upper vertical pipe section and the lower vertical pipe section. The vertical pipe portion can be centered, thereby facilitating the assembly, and the check valve is configured at the tapered fitting portion, so that the upper vertical pipe portion and the lower vertical pipe portion can be aligned. Can be dismantled, and maintenance can be easily performed by this dismantling.

[Brief description of the drawings]

FIG. 1 is a sectional view of a molten metal hot water supply pump device as one embodiment of the present invention.

FIG. 2 is an exploded perspective view illustrating a connection state between a connection bar and a cylinder rod used in the molten metal hot water supply pump device of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Molten hot-water supply pump apparatus 2 Pump sleeve 2a Discharge port (of a pump sleeve) 3 Plunger 3a Lower end part (of a plunger) 3b Upper end part (of a plunger) 4 Stopper means 5 Molten supply pipe 6 Check valve 7 Closed insulation furnace 8 Injection sleeve 8a Hot water supply port (of injection sleeve) 9 Air cylinder (driving means) 11 Furnace lid 12 Plunger guide 13 Stopper receiver 14 Stopper 15 Connecting bar 16a Step 20 Upper vertical pipe 21 Lower vertical pipe 22 Poppet A (In furnace) B Surface level (in molten metal supply pipe) G Oxidation resistant gas M Molten metal

Claims (4)

[Claims] 1. A pump sleeve which is immersed and installed in a molten metal of a sealed insulated furnace into which an oxidation-resistant gas of the molten metal is injected, a lower end of which is fitted to the pump sleeve so as to be vertically movable and an upper end of the pump sleeve. A plunger installed and connected to driving means installed outside the closed insulated furnace; stopper means installed outside the closed insulated furnace to regulate a lower limit position of the plunger; and a discharge port and an injection port of the pump sleeve. A molten metal supply pipe in which an antioxidant gas for molten metal is injected into an internal space portion by connecting a hot water supply port of a sleeve and a molten metal supply pipe which is installed at an intermediate portion of the molten metal supply pipe and closes a surface of the molten metal in the piping to the hot water supply port. A hot-water supply pump device, comprising: 2. The molten metal hot-water supply pump device according to claim 1, wherein the plunger is vertically movably supported by a plunger guide provided above a furnace lid of the closed insulated furnace. A molten metal hot water supply pump device that is installed. 3. The molten metal hot-water supply pump device according to claim 2, wherein the stopper means includes a stopper receiver detachably attached to an intermediate position between the driving means and the plunger guide, and a stopper receiver. A stopper mounted to adjust the position in the up-down direction and a connecting bar for detachably connecting the driving means and the plunger are provided, and the lower movement of the plunger abuts on the stopper to regulate the lower limit position of the plunger. A molten metal hot water supply pump device comprising a step portion. 4. The molten metal feed pump device according to claim 1, wherein an upper part of the molten metal supply pipe projects upward from a furnace lid of the closed heat insulation furnace and the molten metal supply pipe has an upper part. An upper vertical pipe portion which communicates with a hot water supply port and has a lower portion opened by being immersed in the molten metal of the closed insulated furnace; The lower vertical pipe portion communicating with the outlet is configured to be taperedly fitted so that the portions opened by the downward pressing of the upper vertical pipe portion are detachable from each other, and the check valve is formed by the taper fitting. A molten metal hot water supply pump device comprising a poppet arranged in a pipe at a joint portion.