A multi-cavity scroll vacuum pump

Abstract

The invention relates to a multi-cavity vortex vacuum pump, which breaks the traditional design idea and proposes a multi-cavity structure design scheme for the first time, and provides an effective means for breaking through the limitations of compression ratio, pumping speed and ultimate vacuum degree. The parallel multi-cavity scroll vacuum pump of the present invention changes the existing double-sided, multi-head and other structural forms, realizes simultaneous pumping through the parallel multi-chamber structure, effectively improves the pumping speed and working efficiency, and makes the pump body The structure is more compact. The series-type multi-cavity scroll vacuum pump of the present invention changes the existing double-stage, multi-vortex and other structural forms, and adopts the existing double-stage, multi-vortex structural forms of the vacuum pump, which is useful for realizing a lower ultimate vacuum degree and It is difficult to achieve a higher compression ratio, so scroll vacuum pumps with more stages can only be designed, which also leads to higher leakage rates. The pump body of the present invention is not only simple and compact in structure, but also has more The performance of the series scroll vacuum pump is much lower at the same time.

Description

technical field [0001] The invention belongs to the technical field of dry vacuum pumps, in particular to a multi-cavity scroll vacuum pump. Background technique [0002] With the rapid development of industries such as semiconductors, new materials and biopharmaceuticals and the continuous maturity of vortex theory, coupled with people's urgent requirements for a clean and oil-free vacuum environment, technicians from Japan and the United States took the lead in applying vortex theory to vacuum acquisition equipment The oil-free scroll vacuum pump has been successfully developed, and the oil-free scroll vacuum pump has the characteristics of clean and oil-free, wide working pressure range, reliable performance, small torque change and strong ability to adapt to harsh operating conditions. [0003] With the deepening of research, more and more oil-free scroll vacuum pumps with structural improvements have been developed and applied. The following are some typical oil-free sc...

AI Technical Summary

Problems solved by technology

[0004] ① The Chinese patent application number 201410804998.0 discloses a double-sided scroll dry vacuum pump, which uses a bellows to seal and isolate the outer circumference of the first scroll working chamber from the outer circumference of the second scroll working chamber. The tube provides sealing and prevents the rotation of the moving plate. However, since the bellows are in motion during work, the bellows must have good flexibility to ensure the performance of the vacuum pump. Most of the bellows on the market at this stage Insufficient flexibility, which will have a considerable impact on the performance of the vacuum pump, and the vacuum pump does not have the ability to further increase the pumping speed;

[0005] ②A Chinese patent with application number 201310085446.4 discloses a scroll vacuum pump with an integral pump casing, which adopts a single cantilever eccentric main shaft structure, and the compression scroll line increases by 1 / 3 (the same diameter scroll), and the same diameter The scroll disc has fewer leakage points and lower ultimate vacuum; the vacuum pump adopts an integral pump casing structure, although it has the characteristics of less parts, small volume and light weight, but the vacuum pump does not have the ability to further increase the compression ratio and pumping speed;

[0006] ③The Chinese patent application number 200920106785.5 discloses a scroll dry vacuum pump, which reduces the friction between the curved tooth surface of the moving disk and the static disk by correcting the curved tooth involute of the static disk and the moving disk , and solved the problems of high noise of the vacuum pump and serious wear between the moving plate and the static plate, but the vacuum pump did not involve how to increase the compression ratio and pumping speed;

[0007] ④ The Chinese patent application number 200810013021.1 discloses a small pumping speed oil-free scroll vacuum pump, which adopts a double-sided symmetrical scroll structure and has the advantages of compact structure, small volume and low ultimate pressure, but the vacuum pump mainly Aiming at the 8L / s products in the domestic market, a 4L / s small pumping speed vacuum pump was developed. Due to the limitation of the structure, the vacuum pump does not have the ability to increase the pumping speed;

[0008] ⑤ Chinese patent application number 200420030463.4 discloses a multi-vortex double-sided scroll vacuum pump, the working surfaces of the front and rear static scrolls and movable scrolls are all provided with 2 to 6 scrolls, and the scrolls are circular One of the involutes and Archimedes spirals, through the cooperation of multiple vortex lines, the air is pumped at the same time, so that the pumping capacity of the vacuum pump is stronger and the work efficiency is improved. However, because the double-sided scroll vacuum pump is composed of Composed of two stator scrolls and one rotor scroll, the two sides of the rotor are composed of scroll bodies, which require high symmetry and are extremely difficult to locate during processing. At the same time, the vacuum pump adopts a through-type eccentric spindle structure, resulting in complex structure and low rotation speed. The shortcomings of many parts, high leakage rate, small compression, high friction coefficient and high noise, and the vacuum pump cannot provide greater pumping speed;

[0009] ⑥The Chinese patent application number 200320105195.3 discloses a single-side scroll oil-free vacuum pump, which adopts the form of a single-side scroll and uses the scroll profile of a combined curve to increase the scroll wall of the inner ring, effectively Reducing the backflow of gas along the axial gap can increase the ultimate vacuum; however, since the vacuum pump adopts the form of a single-sided scroll, when the pumping speed is required to be high, a large scroll expansion size is required. This will cause the structure of the vacuum pump to become very large, which cannot meet the actual design requirements

[0010] 7. The Chinese patent application number 97219914.4 discloses a double-sided oil-free scroll vacuum pump, which has sealing grooves on the rotor and stator scroll end faces, and small holes are drilled at regular intervals in the sealing grooves. Elastomer is installed inside, so that it can have better sealing performance, and it is also equipped with a gas ballast valve, which can have high compression efficiency and exhaust efficiency; however, because the vacuum pump is limited by the double-sided scroll structure, its It is impossible to further increase the compression ratio and pumping speed;

[0011] ⑧ U.S. Patent Publication No. US2013 / 0315765 (A1), which discloses a three-stage scroll vacuum pump, which realizes three stages in series in the axial direction, effectively reduces the ultimate vacuum degree, and is provided with cooling at each stage The device uses spiral heat dissipation ribs; however, the transmission and cooling structure of the vacuum pump is relatively complicated, and its leakage rate is high, which has a lot of restrictions on further expanding the ultimate vacuum of the vacuum pump.

[0012] It can be seen from the above-mentioned several typical oil-free scroll vacuum pumps that although their respective advantages are obvious, there are more or less limitations in breaking through the compression ratio, pumping speed and ultimate vacuum degree. How to break through the above-mentioned Restricting and expanding the development direction of oil-free scroll vacuum pumps has become an urgent problem to be solved at this stage

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