JPS60142090A - Multi-stage gas-discharge type rotary vacuum pump - Google Patents

Abstract

PURPOSE:To aim at miniaturizing a rotary vacuum pump of multi-stage gas-discharge type, at reducing the drive power thereof, and as well at enhancing the gas-discharge efficiency thereof, by forming a low pressure side operating chamber having a large volume and a high pressure side operating chamber having a small volume in a cylinder chamber so that multi-stage gas discharge may be carried out with only one set of a rotor and a stator. CONSTITUTION:A rotor 4 is disposed in a cylinder 3 at a position where the rotor 4 divides the cylinder chamber 3 into two parts, asymmetrically in one diametrical direction thereof, so that there are provided, in the cylinder chamber 3, a low pressure side operating chamber 6 having a large volume and a high pressure operating chamber 7 having a small volume in order to enhance the efficiency of gas-discharge. With this arrangement low pressure side gas is sucked into the large volume operating chamber 6 through a port 9 in association with the movement of a vane 5 and is discharged through a discharge valve 11 which is opened. The discharged gas is transferred under pressure through a discharge port 10 and a communication hole 14 and is introduced into the small volume operating chamber 7 where the gas is subjected to a gas-discharge process, and is then discharged to the atmosphere through a discharge port 15. With this arrangement multi-stage gas-discharge may be carried out with only one set of a rotor 4 and a stator 2, thereby miniaturization of the multi-stage gas-discharge type rotary vacuum pump and reduction of drive power thereof may be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a multi-stage single-gas rotary vacuum pump that performs multi-stage evacuation using a set of rotors and data.

(Prior Art) In most conventional rotary vacuum pumps, one working chamber is formed within the cylinder chamber, as seen in the Goo γ type, for example.

Conventionally, when attempting to create a high vacuum with such a rotary vacuum pump, multiple sets of rotors and data are connected in tandem via a common rotor shaft, and the discharge ports of each pump are By connecting the suction port and the suction port, multi-stage exhaust was created.

However, such a configuration has disadvantages in that the device becomes larger and more complex, and the driving power increases.

(Objective of the Invention) The object of the present invention is to miniaturize the device and reduce the driving power by performing multi-stage exhaust using one set of rotors and data.

(Structure of the Invention) In order to achieve the above object, this ffff1 light includes a rotor that is horizontally suspended rotatably in a cylinder chamber and partitions the cylinder chamber into a plurality of working chambers, and a rotor that moves forward and backward in the radial direction of the rotor. A multi-stage 1') F-type rotary vacuum pump comprising a plurality of vanes capable of being intoxicated and a communication passage connecting the discharge port of the previous-stage working chamber and the suction port of the next-stage working chamber, It is characterized in that the volume of the stage side working chamber is smaller than the volume of the previous stage side working chamber.

(Description of an Embodiment) The attached drawing shows a two-stage exhaust type rotary vacuum pump according to an embodiment of the present invention. In the figure, a casing 1 accommodates a stator 2 having a substantially cylindrical inner circumference.

At the front and rear of the stator 2, a Freon 1 hexide block and a rear side block (not shown) are respectively attached, and an elliptical cylinder chamber 3 is formed by these blocks.

A rotor 4, which has a plurality of vanes 5 installed in the cylinder chamber 3 so as to be able to advance and retreat in the radial direction, is rotatably mounted horizontally, and the rotor shaft 4a is attached to the floated side block and the rear side block. It is a support.

The rotor is installed at a position that asymmetrically bisects the cylinder chamber 3 in the longitudinal direction, and as a result, crescent-shaped working cavities 6 and 7 with different volumes are formed on both sides of the cylinder chamber 3 in the longitudinal direction. .

The stator 2 has a first suction boat 9 communicating with the large-volume work chamber 6. Discharge boat 1OJ3J: Small volume work chamber 7
A second suction boat 13° and a discharge boat 15 communicating with
is formed. J, ta, each discharge bow 1 to 10.1
Discharge valves 11. , 16 are attached.

The discharge boat 10 includes a stator 2 and a casing 1.
It communicates with the space 12 formed between, and this space 1
2 communicates with the small-volume work chamber 7 through a communication hole 1/I provided perpendicularly to the second suction boat 13.

Furthermore, the first suction bows 1-0 communicate with the low-pressure gas side via the suction port 8 that opens on the side of the controller 1 and the reed block, and the discharge bows 1-15 communicate between the stator 2 and the casing 1. It communicates with the outside through a space 17 formed in the rear side block and a vent formed in the rear side block.

With this configuration, when the rotor 4 rotates clockwise, the vanes 5 protrude and their tips come into sliding contact with the inner wall surface of the cylinder, and air is sucked and extracted in each working chamber 6.7.

First, in the large-volume work chamber 6, low-pressure gas is sucked in through the suction port 8 and the first suction boat 9 by the movement of the vane 5 as the rotor 4 rotates, and then the discharge valve 11 is opened to draw υ1 air. . Exhaust gas is discharged from 1 to 10. The second suction boat 1 via the space 12 and the communication hole 14
3 to the small volume working chamber 7.

In the small-volume work chamber 7, this exhaust gas is further subjected to exhaust work. As a result, the lively gas hears the discharge valve 16,
U1 is discharged from the discharge boat 15 into the atmosphere.

In this way, a two-stage evacuation is performed with the two working chambers 6.7. At this time, the volume of the work chamber 7 on the low pressure side is large, and the volume of the work chamber 7 on the high pressure side is small, so that the exhaust efficiency is improved.

(Effects of the Invention) Since the present invention is configured as described above, multi-stage activation is possible with one set of rotor and stator, and it is possible to downsize the device and reduce driving power. At this time, since the volume of the next-stage work chamber is smaller than the volume of the previous-stage work chamber,
The IJI efficiency of the vacuum pump can be increased.

[Brief explanation of the drawing]

The attached figure is a side sectional view showing a two-stage exhaust type rotary vacuum pump according to an embodiment of the present invention. 1...Singing 2...Stator 3...Cylinder chamber 4...Rotor 5...Vane 6.7...Working chamber 9...First suction bow 1-10.15 ...Discharge boat 11.16...Discharge valve 12...Space section 14...Connection hole and above Applicant Seiko Seiki Co., Ltd. Agent fKT Senior Affairs

Claims (1)

[Claims] (1) A rotor that is rotatably suspended horizontally in a cylinder chamber and partitions the cylinder chamber into a plurality of working chambers, a plurality of vanes that are arranged so as to be movable in the radial direction of this 1:1 rotor, and a front stage side A multi-stage exhaust type rotary vacuum pump equipped with a communication passage connecting a discharge port of a working chamber and a suction port of a next-stage working chamber, the volume of the next-stage working chamber being smaller than the volume of the preceding-stage working chamber. A multi-stage exhaust rotary vacuum pump characterized by: