关键词: 圆渐开线, 非对称等壁厚型线, 涡旋齿, 变壁厚型线, 气体力

Abstract:  In view of the problems of low compression ratio and small displacement volume of equal wall thickness profiles， the gas force of the variable wall thickness profile changed greatly and it was difficult to machine and measure， a design method of asymmetric equal wall thickness profiles was proposed using base circle involute. Using this method， the fully engaged asymmetric scroll teeth with equal wall thickness were established， and the calculation formula of the working chamber volume was derived. The dynamic change processes of the axial， tangential and radial gas forces exerted on the orbiting scroll tooth were obtained with the spindle angles. The results show that compared with the traditional scroll profiles with equal wall thickness and variable wall thickness profile， the displacement volume of the newly constructed asymmetrical scroll profiles with equal wall thickness is increased by 25.99% and 7.82% respectively， and the compression ratio is increased by 19.70% and 2.04% respectively. While the variation range of the axial， tangential and radial gas forces is significantly reduced. It also shows that the asymmetric scroll profiles with equal wall thickness may give better consideration to the advantages of the traditional profiles， and has more superiorities in volume performance and dynamic performance. 

Key words: base circle involute, asymmetric profile with equal wall thickness, scroll teeth, variable wall thickness profile, gas force