JP3574220B2 - Vacuum pump device - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a vacuum pump device that combines an ejector, a tank, and a circulation pump, and more particularly to a vacuum pump device that can increase the suction efficiency of the ejector and maintain the pump efficiency of the circulation pump high. A combined vacuum pump using an ejector ejects a driving fluid such as water to a nozzle in the ejector by a circulating pump, generates a suction force in the ejector by the velocity energy of the fluid, and sends a fluid such as gas or vapor to the ejector. It is used for various vacuum sources such as exhaust elimination of exhaust gas and recovery of steam.
[0002]
[Prior art]
As a conventional vacuum pump device, for example, a device as disclosed in Japanese Patent Publication No. 57-32240 has been used. This is a device in which a diffuser of an ejector communicates with a suction port of a spiral pump as a circulation pump through an open tank, and a cooling water supply passage for supplying cooling water to the open tank and a control valve are provided. The vacuum suction force at the ejector can be maintained at a predetermined value by controlling the temperature of the circulating fluid passing through the ejector.
[0003]
[Problems to be solved by the present invention]
The above-described conventional vacuum pump device has a problem that a sufficient suction force cannot be obtained depending on the amount of circulating fluid passing through the ejector. This is because the ejector and the diffuser are installed vertically upward from the bottom in the tank, and especially when the circulation flow rate is small, the fluid discharged from the ejector nozzle is easily affected by gravity. This is because the discharged flow is disturbed by the sucked fluid, and a sufficient suction force is not generated.
[0004]
In addition, if the ejector and diffuser are installed vertically downward from the top, it is possible to prevent the suction force from decreasing due to the effect of gravity.However, when the ejector sucks a large amount of gas such as air, The pump may draw the gas and the pump efficiency may be reduced.
[0005]
Accordingly, it is an object of the present invention to obtain a sufficient ejector suction force while preventing a decrease in pump efficiency due to gas suction.
[0006]
[Means for Solving the Problems]
The configuration of the vacuum pump device of the present invention is as follows. At least a part of the ejector or a part of the diffuser is disposed in the tank, the tank and the ejector are connected via a circulation pump, the ejector is disposed vertically downward from above, and a partition member is provided on the outer periphery of the diffuser. in that place, by attaching a collision portion for separating the gas and liquid by the difference in mass fluid collides with the lower outlet portion of the diffuser, to connect the suction port and the tank of the circulation pump, the discharge port of the circulating pump And the ejector, and the circulation pump supplies the fluid in the tank to the ejector .
[0007]
[Action]
By disposing the ejector vertically downward from above, the discharge flow is not disturbed by the influence of gravity on the circulating fluid, and the suction force of the ejector does not decrease.
[0008]
By placing the partition member on the outer periphery of the diffuser and attaching the collision part below the outlet, the fluid that has exited the diffuser first collides with the collision part, and the gas and liquid are separated by the difference in mass . Since the gas is light, it stays inside the partition member on the outer periphery, and the liquid falls to the lower part. That is, gas-liquid is separated into and out of the partition member. By discharging the gas inside the partition member to the outside and sucking only the liquid stored in the lower part by the circulation pump, the pump efficiency does not decrease.
[0009]
【Example】
The illustrated embodiment will be described in detail.
FIG. 1 shows an overall configuration diagram of a vacuum pump device. A vacuum pump device is constituted by the tank 1 and the ejector 2, and the circulation pump 3 disposed between the tank 1 and the ejector 2. The ejector 2 is attached to the upper part of the tank 1, and the lower end 7 of the diffuser 6 is formed in the tank 1 by opening. The partition members 4 and 5 are arranged on the outer periphery of the diffuser 6, and a collision plate 8 as a collision portion is attached below the lower end 7 of the diffuser 6. The partition members 4 and 5 are arranged concentrically with the diffuser 6, and the upper end of the partition member 4 is attached by welding to the inner surface of the upper plate of the tank 1. The partition member 5 is concentric with the partition member 4 by the rib 9. Attach. A plurality of through holes 10 are provided in the upper part of the partition member 4. The collision plate 8 is provided with an uneven portion on the end surface on the diffuser 6 side, and is mounted so as to be located between the lower ends of the partition members 4 and 5.
[0010]
The lower opening 11 of the tank 1 is connected to the suction port of the circulation pump 3, and the discharge port 12 of the circulation pump 3 is connected to the ejector 2. Although not shown, the ejector 2 is provided with a nozzle therein and a suction chamber around the nozzle, and connects the discharge port 12 of the circulation pump 3 to the nozzle portion, and connects the suction chamber to the suction passage 13. The suction passage 13 sucks exhaust gas, collected steam, and the like.
[0011]
An air communication pipe 16 is attached to the upper part of the tank 1 via a valve 15, and a blow pipe 17 is attached to the lower part.
[0012]
Next, the operation will be described.
By driving the circulation pump 3 to supply the fluid in the tank 1 to the ejector 2, the ejector 2 sucks exhaust gas, steam, and the like from the suction passage 13. The gas such as gas or vapor sucked into the ejector 2 is discharged from the diffuser 6 together with the circulating fluid and collides with the upper surface of the collision plate 8. After colliding with the collision plate 8, the gas having a small mass reaches the inside of the partition member 4 or the inside of the partition member 5 and is discharged to the outside from the atmosphere communication pipe 16. Thereby, gas-liquid is separated. The liquid is sucked by the circulation pump 3 from the opening 11 and circulates again.
[0013]
In this embodiment, an example using two partition members 4 and 5 has been described. However, one partition member may be sufficient, or two or more partition members may be used. Further, in the present embodiment, the example in which the collision plate 8 is used has been described.
[0014]
【The invention's effect】
By placing the ejector vertically downward from the top, the circulating fluid is not affected by gravity, ensuring a sufficient suction force with the ejector, and by arranging the collision plate and the partition member Gas and liquid can be separated, and no gas such as exhaust gas or air is sucked into the circulation pump, and the pump efficiency does not decrease.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional configuration diagram of an embodiment of a vacuum pump device of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Tank 2 Ejector 3 Circulation pump 4 Partition member 5 Partition member 6 Diffuser 8 Impact plate 13 Suction passage

Claims (1)

At least a part of the ejector or a part of the diffuser is disposed in the tank, the tank and the ejector are connected via a circulation pump, the ejector is disposed vertically downward from above, and a partition member is provided on the outer periphery of the diffuser. in that place, by attaching a collision portion for separating the gas and liquid by the difference in mass fluid collides with the lower outlet portion of the diffuser, to connect the suction port and the tank of the circulation pump, the discharge port of the circulating pump A vacuum pump device , wherein the fluid in the tank is supplied to the ejector by the circulation pump .

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