| 摘要 |
1,197,432. Rotary positive-displacement machines. SVENSKA ROTOR MASKINER A. B. July 11, 1967 [July 29, 1966], No.34217/66. Heading F1F. In a rotary positive-displacement machine e.g. a compressor, of the externally-meshing screw-type the profiles of the flanks 50, 52 of each groove in a female rotor 26 are such that a line of contact 82 between the flank 52 and a flank 62 of a land 54 on a male rotor 12 travels towards the bottom of the groove so that torque acting on the female rotor due to trapping of working fluid in a pocket 76 is minimal. The profiles of the flanks 50, 52 are an epicycloidal curve and an arc of a circle, together with a line tangential thereto respectively. The profiles of the flanks 60, 62 of the land 54 are an epicycloidal curve and an envelope curve generated by the flank 52, respectively. Details of these profiles and minor modifications thereof, Figs. 2 and 4 and Figs. 6 to 7d (not shown), are given in the Specification. In the modification according to Figs. 6 to 7d sealing strips (110) are formed on the lands of the male rotor. Liquid for sealing purposes may be injected into the working spaces through channels (88), Fig. 2. |
