JPH08312600A - Vacuum pump device - Google Patents

Abstract

PURPOSE: To provide a vacuum pump device capable of keeping high the suction efficiency of an ejector and the pumping efficiency of a circulating pump. CONSTITUTION: An ejector 2 is mounted to the upper part of a tank 1. The lower end 7 of a diffuser 6 is opened into the tank 1. Partition wall members 4, 5 are disposed on the outer periphery of the diffuser 6. A collision plate 8 is mounted below the diffuser 6. The opening 11 in the lower part of the tank 1 is connected to a circulating pump 3 and a discharging port 12 of the circulating pump 3 is connected to the ejector 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum pump device combining an ejector, a tank and a circulation pump, and more particularly,
The present invention relates to a device capable of increasing the suction efficiency of an ejector and maintaining a high pump efficiency of a circulation pump. A combined vacuum pump using an ejector causes a drive fluid such as water to be ejected by a circulation pump to a nozzle in the ejector, and a suction force is generated in the ejector by the velocity energy of the fluid.
It sucks fluids such as gas and steam into the ejector, and is used as various vacuum sources such as suction / removal of exhaust gas and recovery of steam.

[0002]

2. Description of the Related Art As a conventional vacuum pump device, for example, the one shown in Japanese Patent Publication No. 57-32240 has been used. This is one in which a diffuser of an ejector and a suction port of a spiral pump as a circulation pump are connected to each other through an open tank, and a cooling water supply passage and a control valve for supplying cooling water to the open tank are provided. The temperature of the circulating fluid passing through the ejector can be controlled to maintain the vacuum suction force at the ejector at a predetermined value.

[0003]

The above-mentioned conventional vacuum pump device has a problem that a sufficient suction force cannot be obtained depending on the amount of the circulating fluid passing through the ejector. This is because the ejector and diffuser are installed in the tank from the bottom to the top in the vertical direction, and especially when the circulating flow rate is low, 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.

Further, if the ejector and the diffuser are installed vertically from top to bottom, it is possible to prevent a decrease in suction force due to the influence of gravity, but when the ejector sucks a large amount of gas such as air. In addition, the circulation pump may inhale the gas and reduce the pump efficiency.

Therefore, it is a technical object of the present invention to prevent a decrease in pump efficiency due to suction of gas and to obtain a sufficient suction force of an ejector.

[0006]

The structure 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 arranged in a tank, and the tank and the ejector are connected via a circulation pump. The ejector is arranged vertically from top to bottom, and the diffuser is arranged. A partition member is arranged on the outer periphery of the chamber, and a collision unit against which fluid collides is attached below the outlet of the diffuser.

[0007]

By arranging the ejector vertically from the upper side to the lower side, the circulating fluid is not affected by gravity and the discharge flow is not disturbed, and the suction force of the ejector does not decrease.

Since the partition member is arranged on the outer periphery of the diffuser and the collision portion is attached below the outlet portion, the fluid exiting the diffuser first collides with the collision portion and the difference in mass causes gas and liquid. Separates. Since the gas is light, it collects inside the partition wall member on the outer periphery, and the liquid drops to the lower part.
That is, gas and liquid are separated into the inside and outside of the partition member. By discharging the gas inside the partition member to the outside and sucking only the liquid accumulated in the lower part by the circulation pump, the pump efficiency does not decrease.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The illustrated embodiment will be described in detail. FIG. 1 shows an overall configuration diagram of the vacuum pump device. Tank 1 and ejector 2
And a circulation pump 3 arranged between the tank 1 and the ejector 2.
And constitute a vacuum pump device. The ejector 2 is attached to the upper part of the tank 1, and the lower end portion 7 of the diffuser 6 is formed in the tank 1 by opening it. 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 portion 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 welded and attached to the inner surface of the upper plate of the tank 1. Install. A plurality of through holes 10 are provided above 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 attached so as to be positioned between the lower end portions of the partition members 4 and 5.

Lower opening 11 of tank 1 and circulation pump 3
Of the circulation pump 3 is connected to the ejector 2. Although not shown, the ejector 2 has a nozzle and a suction chamber around the nozzle.
The discharge port 12 of the circulation pump 3 is connected to the nozzle portion, the suction chamber is connected to the suction passage 13, and the suction passage 13 is connected.
The exhaust gas and the recovered steam are sucked from the air.

An atmosphere communication pipe 16 is attached to the upper portion of the tank 1 via a valve 15, and a blow pipe 17 is attached to the lower portion.
Attach.

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 the gas or the vapor sucked by 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 the collision with the collision plate 8, the gas with a small mass reaches the inside of the partition member 4 or the inside of the partition member 5 and is removed from the atmosphere communication pipe 16 to the outside, and the liquid with a large mass falls below the partition members 4, 5. As a result, gas-liquid is separated. The liquid is sucked from the opening 11 by the circulation pump 3 and circulates again.

In this embodiment, the two partition members 4,
Although the example using 5 is shown, one partition member may be sufficient, or two or more partition members may be used. Further, in the present embodiment, an example in which the collision plate 8 is used is shown, but instead of the plate 8, the inner surface of the bottom portion of the tank 1 may be used as the collision portion.

[0014]

Since the ejector is installed vertically downward from above, the circulating fluid is not affected by gravity, a sufficient suction force can be secured by the ejector, and the collision plate and the partition member. By arranging, the gas and liquid can be separated, the exhaust gas and the gas such as air are not sucked into the circulation pump, and the pump efficiency does not decrease.

[Brief description of 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]

 1 Tank 2 Ejector 3 Circulation Pump 4 Partition Member 5 Partition Member 6 Diffuser 8 Collision Plate 13 Suction Passage

Claims (1)

[Claims] 1. A structure in which at least a part of an ejector or a part of a diffuser is arranged in a tank, and the tank and the ejector are connected via a circulation pump, the ejector is arranged vertically from top to bottom. A vacuum pump device, characterized in that a partition member is disposed on the outer periphery of the diffuser, and a collision portion against which fluid collides is attached below the outlet portion of the diffuser.