All-engaged variable wall thickness vortex vacuum pump

Abstract

The invention discloses an all-engaged variable wall thickness vortex vacuum pump. An inner side engagement molded line and an outer side engagement molded line of a movable vortex gear of the vortexvacuum pump and an inner side molded line and an outer side molded line of a stationary vortex gear are obtained from a vortex middle line formed by a circle involute and a high-order continuous curvein the normal direction in an equally-spaced manner. Molded lines of the outermost circles of the obtained vortex gears can be involved into engagement; the air suction capacity can be increased; inaddition, the vortex number required under the high pressure-ratio and large air capacity requirements is small; and the leakage rate is low. The vortex middle line is formed by connecting two arcs inthe center, wherein the two arcs are different in radius. When a final engagement point of a stationary vortex coincides with a final engagement point of a movable vortex, two formed minimum closed working cavities are unequal in volume. The volume ratios of two air suction cavities to the corresponding minimum closed working cavities can be equal, and thus the problems that at the moment when anexhaust port of an existing all-engaged vortex vacuum pump is opened, efficiency of the vortex vacuum pump is lowered and a vortex disc vibrates due to mixing of gases at different pressures are solved; and work efficiency of the vortex vacuum pump is improved.

Description

technical field [0001] The invention belongs to the technical field of scroll vacuum pumps, and in particular relates to a movable scroll and a static scroll of a full mesh variable wall thickness scroll vacuum pump suitable for an oil-free lubricating vacuum system. Background technique [0002] Scroll vacuum pump is a positive displacement fluid machine. Due to its simple structure, few parts, stable operation and low vibration and noise, it has been widely used in oil-free vacuum environment, semiconductor industry, scientific instrument industry, and medical equipment industry. Existing scroll vacuum pumps usually use a circular involute as the scroll tooth profile, and the profiles of the outermost ring of the movable scroll and the fixed scroll cannot all participate in the meshing during operation, resulting in a large scroll structure , the structure is not compact; when the internal volume ratio of the scroll vacuum pump is required to be high, the number of scroll ...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the unequal volume ratio of the two sets of suction chambers and the corresponding minimum closed working chambers of the existing fully meshing scroll vacuum pump due to the unequal volumes of the suction chambers formed, the gas with different pressures during the exhaust process Mixing leads to a decrease in the efficiency of the scroll vacuum pump, and at the same time causes the problem of scroll vibration, and the existing scroll vacuum pump requires a large number of scroll turns for a single-shaped scroll under the requirements of high internal volume ratio and large suction volume. To solve the problem of long leakage line, the present invention proposes a fully meshing variable wall thickness scroll vacuum pump, the scroll tooth profile adopts a combination of circular involute and high-order continuous curve; the obtained movable scroll and The outermost profiles of the fixed scroll can participate in meshing to form a working cavity, which reduces the size of the scroll and increases the suction capacity; the proposed scroll profile of the movable scroll and the fixed scroll is determined by the The centerline of the vortex is equidistant from the normal direction of the centerline of the vortex. The centerline of the vortex is connected by two arcs with unequal radii at the center, and the position of the connection point does not pass through the center of revolution. The thickness of the tooth head at the center of the fixed scroll is not equal; at the center of the revolution, the positions of the final meshing point of the fixed scroll and the final meshing point of the moving scroll are asymmetrical with respect to the center of the revolution, ensuring that the two sets of suction chambers and The volume ratio of the corresponding minimum closed working chamber is equal, which solves the problem that the efficiency of the scroll vacuum pump is reduced due to the mixing of gases at different pressures during the exhaust process of the existing fully meshing scroll vacuum pump, which causes scroll vibration and overturning.

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