Geometric design and performance analysis of a novel smooth rotor profile of claw vacuum pumps

In view of the problems that the existing rotor profiles of claw vacuum pumps contain non-smooth connection points, a novel smooth rotor profile was proposed in this paper. The proposed profile, which can achieve correct meshing, is composed of 6 circular arcs and 3 equidistant curves of epicycloid, and its design procedures as well as equations were given. The effects of geometric parameters on the shape and performances of the claw rotor were analyzed. Besides, 3D numerical simulations of the entire working process of the claw vacuum pump with the proposed rotor profile were performed, and its performances were analyzed. The study results indicate that the proposed rotor profile of claw vacuum pumps, compared with the existing rotor profiles, has remarkable advantages of better meshing performance, smaller carryover and better mechanical properties. Thus, the new rotor profile designed and the data obtained can be applied to the design and optimization of claw vacuum pumps.