JPS5852397Y2 - Molten metal pumping device - Google Patents

Description

[Detailed description of the invention] This invention relates to a molten metal pumping device that can continuously transport molten metal, such as non-ferrous metal, which is easily solidified at high temperatures, to a high place, just like pumping up water.

Although vertical pumps generally have excellent efficiency, they cannot be used to pump molten metal at high temperatures.

Although the present invention has some efficiency, it has a high temperature of 300~
The purpose is to be able to pump up molten metal at 800°C, and also to be able to pump it up again even if pumping is temporarily stopped.

An embodiment of the present invention will be described with reference to drawings. A cylindrical suction pipe 2 has a plurality of small holes 1, 1 for suctioning molten metal in its lower part. A pump chamber 3 of a slightly larger diameter is concentrically provided in the upper part of the pipe, and The main body 5 is attached to the upper part of the support pipe 4 connected to the upper part of the chamber 3.

The lower part of a rotary shaft 7 rotatably supported by bearings 6, 6 provided in this main body is located slightly above the support tube 4, and a shaft 9 is connected to the lower end of this support tube 4 via a joint 3. An impeller 17 located at the lower end is rotatably located within the pump chamber 3.

A plurality of discharge ports 10.degree. 10 having openings sufficiently long in the vertical direction are provided on the wall surface of the same circumference of the support tube 4, located below the joint 8.

A downward slope 3a is provided on the bottom surface of the pump chamber 3 in the direction of the opening of the upper end of the suction pipe 2, so that the molten metal does not remain in the pump chamber 3 when the suction pipe 2 is taken out from the crucible 20.

Further, the upper surface of the pump chamber 3 is provided with a gently tapered upward slope 3b, and a tapered hole 11 is further formed upward from the upper end of the upward slope 3b.

Reference numeral 12 denotes a discharge pipe having an upright portion connected to one side of the pump chamber 3, and an outlet 13 is provided at the upper end.

Reference numeral 14 denotes a variable speed motor attached to the upper part of the main body 5, and the variable speed motor 14 and the upper part of the rotating shaft 7 are interlocked by an interlocking means 15 such as a chain or a belt.

Further, the rotating shaft 7 and the bearings 6, 6 are cooled by air blowing from an air blower 16 installed inside the main body.

Then, the suction pipe 2 is inserted into the molten metal of the crucible 20 to a point where the pump chamber 3 is immersed, and the variable speed motor 21 is driven to transmit the rotation of the variable speed motor 21 to the rotating shaft 7 using a belt, chain, etc. The rotation of the wheel 10 sucks molten metal into the pump chamber 3.

It is dangerous to rotate the impeller 10 with this pump chamber sealed and air trapped, but in this application, the small hole 1
．． As the molten metal enters the pump chamber 3, the air in the pump chamber 3 easily rises along the upward slope 3b, and the generated oxides can float together, so there is no danger.

Further, the molten metal in the pump chamber 3 is rotated at high speed by the impeller 10, and most of it is pressurized and sent to the discharge pipe 12 by centrifugal force.
However, a part of the molten metal rises within the tapered part 11 while rotating.

The upper part of the pump chamber is provided with a tapered hole 11 so that the distance from the shaft 9 gradually narrows, so the volume of the molten metal is narrowed by the wall surface of this taper hole 11, and the pressure is reduced. As a result, a reaction occurs in which the molten metal rising inside the tapered hole 11 is pushed back.

Therefore, the leakage of molten metal from the outlet 10° 10 provided in the support tube 4 is smaller than in the case without the tapered hole 11, but on the other hand, the centrifugal force generated in the pump chamber 3 is increased. As a result, a larger amount of the molten metal is supplied into the discharge pipe 12 and rises, and the amount of molten metal transferred from the outlet 13 at the tip of the discharge pipe 12 to the gutter 21 increases due to the rotation of the variable speed motor 21.
Further, the molten metal surface 22 shown in FIG. 2 descends within the crucible 20 over time.

If it becomes necessary to temporarily stop sucking up the molten metal when the molten metal surface 22' has fallen below the position of the pump chamber 3, it will be impossible to pump up the molten metal again if the rotation of the impeller 170 is stopped. The molten metal is discharged from the discharge port 10 by slowing down the rotation speed of the variable speed motor 21 and keeping the water head 23 of the molten metal in the discharge pipe 12 lower than the outlet 13 and higher than the discharge port 10 of the support pipe (Fig. 3). Continuing to keep the inside of the pump chamber 3 in a vacuum.

In this state, if the molten metal is to flow out from the outlet 13 again, the variable speed motor 21 is rotated at a high speed to increase the pressure in the pump chamber 3, and the water head 23 in the discharge pipe 12 rises again.
The molten metal can flow out from the outlet 13.

In addition, since the discharge port 10 provided in the support pipe 4 functions as an outlet for the molten metal circulated by the impeller 17, the molten metal does not solidify in the pump chamber, suction pipe, or support pipe, and the shaft 9 or This is convenient for removing oxides adhering to the inner surface of the support tube 4, and also serves as a peephole for viewing the inside of the pump chamber, which has the advantage of making work easier.

Further, unlike a water pump, the blades of the impeller 17 cannot be adjusted.

For this reason, this impeller is initially rotated at high speed by the variable speed motor 14 to prevent the molten metal from solidifying in the discharge pipe 12, but after discharge, the speed of the motor is adjusted to continue discharging the required amount, thereby increasing the head. Adjust the rotation speed according to the change.

If a motor with constant rotation is used, it is impossible to pause during discharge.

The present invention as described above has the following effects.

■ There is an upwardly tapered hole between the outlet provided at the bottom of the support tube and the pump chamber.
It generates the function of pushing back the molten metal pushed up from below downwards to prevent leakage from the discharge port as much as possible, but it also has the advantage of increasing the amount of flow out from the tip of the discharge pipe and enhancing the pumping effect. Since the outlet is provided with a sufficient opening at the bottom, the molten metal in the support tube leaks from the outlet without rising, so the joint will not be immersed in the molten metal.

■ When pumping molten metal is temporarily stopped by adjusting the speed of the variable speed motor, the impeller in the pump chamber is slowly rotated to pump the molten metal to the suction pipe, pump pipe, support pipe, and crucible. Since it functions as an outlet for the molten metal in the pump chamber during circulation, the molten metal will not solidify.

(2) Each of the discharge ports has a sufficient length in the vertical direction, which is convenient for removing oxides adhering to the shaft and the inner surface of the support tube.

■ This discharge port functions as a peephole to view the pump chamber.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view, FIG. 2 is a cross-sectional view showing the pumping state, and FIG. 3 is a cross-sectional view of the discharge stop state.

Claims (1)

[Scope of utility model registration request] A slightly larger diameter pump chamber 3 is concentrically connected to the suction pipe 2, which has a plurality of small holes 1, 1 in its lower part, and the support pipe 4, which has a plurality of discharge ports 10, 10 in the same circumferential side wall. A tapered hole 11 is provided between the upper part of the pump chamber and the discharge port 10, and a discharge pipe 12 having an upright portion is connected to the negative side of the pump chamber in the tangential direction. The lower part of the rotating shaft 7 is supported in the main body 5 attached to the upper part of the pipe 4 and the lower part is located in the support pipe 4, and is attached and detached with a joint 8 located above the discharge port 10 provided in the support pipe. An impeller 17 provided at the lower end of the freely connected shaft 9 is rotatably located in the pump chamber, and this rotary shaft 7 and a variable speed motor 14 attached to the main body are interlocked, and the rotary shaft is cooled within the main body. blower 1
Molten metal pumping device comprising 6