Novel Roots rotor profile

Abstract

The invention belongs to the field of dry vacuum pumps, and particularly relates to a novel Roots rotor profile. Wherein the end face molded line comprises n curves which are connected end to end, and n is the number of blades of the roots rotor; the first curve is subjected to straight line modification at a tooth root arc envelope line, the tooth root arc envelope line, a curve obtained by cutting out a tooth crest arc by straight line modification at the tooth crest arc, the tooth root arc envelope line and straight line modification at the tooth root arc envelope line are sequentially connected anticlockwise, and the nth curve is obtained by the n first curve arrays; a straight line passing through the rotation center point O and the tooth crest arc center is used as a symmetry axis of the first molded line; the straight line modification at the tooth root arc envelope line and the straight line modification at the tooth root arc envelope line are symmetrical relative to the symmetry axis; the tooth root arc envelope line and the tooth root arc envelope line are symmetrical relative to the symmetry axis; according to the invention, the stress concentration phenomenon at the tooth crest can be effectively reduced, and the high strength is realized.

Description

technical field [0001] The invention belongs to the field of dry vacuum pumps, in particular to a new type of Roots rotor profile. Background technique [0002] The main application fields of dry vacuum pumps include semiconductor technology represented by etching process, chemical industry, polysilicon preparation process in low-pressure chemical vapor deposition, scientific experimental instrument applications, etc. Among them, the market share of dry vacuum pumps in the field of semiconductor applications up to 40%. Taking the semiconductor industry with the most extensive application of dry vacuum pumps as an example, its process environment includes three conditions: clean, medium and harsh, including process types including Load lock, gas delivery, metering, PVD process, PVD pre-cleaning, CVD, PECVD , MOCVD, etc. At present, in order to meet the requirements of different process environments in the semiconductor industry, the combination of different rotor types and t...

AI Technical Summary

Problems solved by technology

Taking the semiconductor industry, which is the most widely used dry vacuum pump, as an example, its process environment includes three conditions: clean, medium, and harsh. The process types included are Load lock, gas delivery, metering, PVD process, PVD pre-cleaning, CVD, PECVD , MOCVD, etc. At present, in order to meet the requirements of different process environments in the semiconductor industry, the combination of different rotor types and the combination of vacuum dry pumps are generally used to solve the problem, but this form is helpful to a certain extent for rapid powder discharge under actual working conditions , but due to the narrow size of the pump chamber, it is still prone to problems such as scratching between the rotors

However, in the current Roots rotor profile based on the conjugate curve, there will still be dust accumulation at the top of the teeth after meshing, which will cause scratches during meshing.

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