CN201696296U

CN201696296U - Vacuum pump structure

Info

Publication number: CN201696296U
Application number: CN2010202242036U
Authority: CN
Inventors: 张振厚; 王光玉; 孔祥玲
Original assignee: Shenyang Scientific Instrument R&D Center of CAS
Current assignee: Sky Technology Development Co Ltd
Priority date: 2010-06-12
Filing date: 2010-06-12
Publication date: 2011-01-05
Anticipated expiration: 2020-06-12

Abstract

The utility model discloses a vacuum pump structure, which comprises a vacuum cavity body, a gear box, a motor cavity, a shield motor, a shaft seal structure, a motor main shaft, a driven shaft, a Roots rotor and the like, wherein the vacuum pump drives the shield motor for use, the shield motor is completely arranged in the motor cavity, the vacuum pump motor main shaft and the driven shaft are in a cantilever structure in the vacuum cavity, are not supported by a bearing, so that the processing and assembly difficulty can be reduced, and probability that the during the working process, the bearing is damaged because of being polluted by a transmission medium in the pump can be reduced. The shaft seal component structure is arranged in the gear box, so that the lubricating oil in the cavity of the motor can be prevented from diffusing into the vacuum cavity, the air passage in the gear box is used for the air to enter the shaft seal component, so that the temperature at the shaft seal is prevented from rising too quickly or the dust can be prevented from entering the shaft seal. The transmission device of the vacuum pump is a gear, and the transmission ratio is 1:1.

Description

A kind of vacuum pump structure

Technical field

The utility model relates to the vacuum equipment field, is a kind of vacuum pump structure specifically.

Background technique

Roots pump is a kind of rotary volume vacuum pump, its structural type is to be developed by Roots blower, its working principle is also similar to Roots blower, majority is vertically mounted in the pump chamber by two " 8 " font rotors, the synchronous backward rotation, and, reach gap sealed purpose, because rotor constantly rotates between rotor, maintain certain interval between rotor and pump case.Pumped gas is drawn between rotor and the pump chamber from suction port, discharges through relief opening again.

The kind of drive of Roots pump roughly is divided into two kinds, the one, motor and gear are placed on the rotor homonymy, driven rotor is driven by the motor terminal direct geared, the torsional deflection of power rotor axle is little like this, the gap can not change greatly because of the driving shaft torsional deflection between rotor, but shortcoming is to arrange three bearings on the driving shaft, increases the assembling and the difficulty of processing of pump, and the gear dismounting is also inconvenient.The another kind of kind of drive be motor and gear in the rotor both sides, the overall structure of this form pump is well-balanced, convenient disassembly is widely adopted, but input torque is big, and the rigidity of main shaft is had requirement.The lubricant housings of Roots pump mainly contains three places: the axle envelope place of main shaft motive sealing, generally use cascade oiling; Spatter oil with gear or disc and guarantee to lubricate at gear and bearing place, and reinforced seal, labyrinth seal or piston ring sealing etc. are adopted in common axle envelope place motive sealing, can not make an envelope place avoid the lubricant oil of gear side to spread in vacuum cavity.

The vacuum pump structure that the utility model relates to is the Roots pump structure, adopt motor and gear structure at homonymy, make pump have the characteristics that gap between lesser trochanter can not change greatly because of the driving shaft torsional deflection of reversing of power rotor axle, and in vacuum chamber, adopt the cantilevered axle structure, reduce bearings, improve the rigidity of axle, avoided the constant and big problem of difficulty of processing of dismounting of pump.And utilize the gland seal assembly structure, diaphragm seal is laid at the two ends of cover, overcoat in sealing, and the Teflon material need not to lubricate, and motive sealing is effective, has avoided the interior lubricant oil of motor cavity to enter in the vacuum pump chamber, pollutes vacuum environment.

The model utility content

For solving the problems of the technologies described above, the purpose of this utility model provides a kind of vacuum pump structure, and concrete scheme is as follows:

A kind of vacuum pump structure comprises vacuum cavity 1, and gear-box 2, motor cavity 3, shield electric machine 4, gland seal assembly 10, electric machine main shaft 5, driven shaft 6, roots rotor 11, described gear-box 2 are arranged between vacuum cavity 1 and the motor cavity 3; Shield electric machine 4 is fixed in the motor cavity 3, and the overhanging end of electric machine main shaft 5 and driven shaft 6 is in the vacuum cavity 1; Roots rotor 11 relies on the expansion set assembly to be fixed on the overhanging end of electric machine main shaft 5 and driven shaft 6; Gland seal assembly 10 is installed in the center of gear-box 2, is enclosed within on electric machine main shaft 5 and the driven shaft 6 blocking-up vacuum cavity 1 and motor cavity 3;

In the utility model, vaccum pump motor main shaft and driven shaft are divided into cantilever structure in vacuum cavity inside, no bearings, concrete structure is: described electric machine main shaft 5 is by shield electric machine 4 centers, support by spring bearing A7 and spring bearing B9, driven shaft 6 is also supported by spring bearing A7 and spring bearing B9, and described spring bearing A7 is in motor cavity 3, and spring bearing B9 is in gear-box 2;

For making near the gas the vacuum pump relief opening partly suck the gear-box top, and send in the gland seal assembly, gas channel 13 is arranged in the described gear-box and be communicated with two pores 12 that are arranged on the gear-box top by two pores 12 at gear-box top;

Described gland seal assembly 10 comprises the diaphragm seal 14 at two ends, cover 15 and hermetically sealed case 16 in the middle sealing;

The material of diaphragm seal is a Teflon in the described gland seal assembly;

Transmission device between electric machine main shaft and driven shaft is a gear, and velocity ratio is 1: 1.

The utlity model has following advantage:

1. the motor in the utility model is a shield electric machine, is placed in the motor cavity, and the motive sealing of rotary main shaft and shield electric machine is converted into the static seal of pump inside, the leakage of having avoided motive sealing to cause.

2. the spring bearing of vacuum pump shaft is all on the motor cavity side, and the extension of axle is a cantilever structure in the vacuum cavity, has reduced processing, assembling difficulty, has reduced bearing and has been subjected to transmission medium pollution in the pump in the course of the work and damage probability.3. the gas channel of gear-box can make gas directly be blown in the axle envelope, avoids temperature rise too fast on the one hand the cooling of axle envelope, and avoiding a small amount of vacuum chamber side dust to enter in the axle envelope on the one hand influences sealing effect.4. the material selection Teflon material of gland seal assembly axis mounting, wear-resistant and good airproof performance.

Description of drawings

Fig. 1 is vacuum pump structure figure;

Fig. 2 is gear box structure figure;

Fig. 3 is seal component architecture figure.

Among Fig. 1: 1, vacuum cavity; 2, gear-box; 3, motor cavity; 4, shield electric machine; 5, electric machine main shaft; 6, driven shaft; 7, spring bearing A; 8, driving gear; 9, spring bearing B; 10, gland seal assembly; 11, roots rotor.

Among Fig. 2: 12, pore; 13, gas channel.

Among Fig. 3: 14, diaphragm seal; 15, cover in the sealing; 16, hermetically sealed case.

Embodiment

The utility model is a kind of vacuum pump structure, and its structural drawing as shown in Figure 1.The vacuum pump cavity is made up of vacuum cavity 1, gear-box 2 and motor cavity 3.Shield electric machine 4 is fixed in the motor cavity 3, electric machine main shaft 5 is by shield electric machine 4 centers, support by the spring bearing B9 that is arranged on the spring bearing A7 in the motor cavity and be arranged in the gear-box, driven shaft 6 is also supported by spring bearing A7 and spring bearing B9, and the overhanging end of electric machine main shaft 5 and driven shaft 6 is in the vacuum cavity 1.Roots rotor 11 relies on the expansion set assembly to be fixed on the overhanging end of electric machine main shaft 5 and driven shaft 6.Gland seal assembly is installed in the center of gear-box 2, is enclosed within on electric machine main shaft 5 and the driven shaft 6 blocking-up vacuum cavity 1 and motor cavity 3.

Shield electric machine 4 energising backs drive electric machine main shaft 5 rotations, and driving gear 8 drives driven shaft 6 and rotates with electric machine main shaft 5 synchronous backwards, rotate thereby drive the roots rotor 11 that is installed on the diaxon, make vacuum pump realize bleeding function.

For making near the gas the vacuum pump relief opening partly suck gear-box 2 tops, and send in the gland seal assembly 10, gas channel 13 is arranged in the described gear-box and be communicated with two pores 12 that are arranged on gear-box 2 tops by two pores at gear-box 2 tops;

The material of diaphragm seal is a Teflon in the described gland seal assembly 10;

The transmission device that electric machine main shaft 5 and driven shaft are 6 is a gear, and velocity ratio is 1: 1.

Claims

1. vacuum pump structure, it is characterized in that: comprise vacuum cavity (1), gear-box (2), motor cavity (3), shield electric machine (4), gland seal assembly (10), electric machine main shaft (5), driven shaft (6), roots rotor (11), described gear-box (2) are arranged between vacuum cavity (1) and the motor cavity (3); Shield electric machine (4) is fixed in the motor cavity (3), and the overhanging end of electric machine main shaft (5) and driven shaft (6) is in the vacuum cavity (1); Roots rotor (11) relies on the expansion set assembly to be fixed on the overhanging end of electric machine main shaft (5) and driven shaft (6); Gland seal assembly (10) is installed in the center of gear-box (2), is enclosed within on electric machine main shaft (5) and the driven shaft (6) blocking-up vacuum cavity (1) and motor cavity (3).

2. by the described vacuum pump structure of claim 1, it is characterized in that: electric machine main shaft (5) is by shield electric machine (4) center, support by spring bearing A (7) and spring bearing B (9), driven shaft (6) is also supported by spring bearing A (7) and spring bearing B (9), described spring bearing A (7) is in motor cavity (3), and spring bearing B (9) is in gear-box (2).

3. by the described vacuum pump structure of claim 1, it is characterized in that: gas channel (13) is arranged in the described gear-box (2) and be communicated with two pores (12) that are arranged on gear-box (2) top.

4. by the described vacuum pump structure of claim 1, it is characterized in that: described gland seal assembly (10) comprises the diaphragm seal (14) at two ends, cover (15) and hermetically sealed case (16) in the middle sealing.