Twin shaft helical gear rotary compressor - has annular grooves in cover and pockets in teeth to balance axial forces

摘要

The rotary compressor has a housing in which a rotor (1) with helical teeth meshes with a rotor (2) with helical grooves, and is designed to balance the forces in axial direction due to the helical shape of the teeth. Pockets (4, 10) are provided in the end faces on the suction side to counteract these forces to the extent which is compatible with the effective life of the roller bearings on the suction side. The pockets connect with annular grooves (3, 11) which communicate with annular grooves (21, 6) on the pressure side via bores (5, 13). The balancing pressure thereby obtained lies between the outlet and inlet pressure and is determined either by the geometry of recesses (7, 14) in the end cover on the pressure side, or of the end face gaps and the profile of the pockets.