SCREW COMPRESSOR WITH VARIABLE COMPRESSION RATIO

摘要

The. invention is a screw compressor (1) comprising: a container body (2); two rotors (3, 4) arranged in the container body (2) with the respective rotation axes (X1, X2) mutually parallel, provided on corresponding side surfaces (6, 7) with helical grooves (5) that mesh with each other to delimit corresponding compression chambers; drive means suited to set the rotors (3, 4) rotating in opposite directions and to compress a fluid contained in the compression chambers; a suction duct (11) and an outlet duct (12) for the fluid, communicating with the compression chambers at the level of corresponding inlet and outlet ends (9, 10) of the rotors (3, 4); shutter means (13) interposed between the rotors (3, 4) and the outlet duct (12). The shutter means (13) comprise a through opening (14) made in the container body (2), arranged so that it faces the side surface (6, 7) of the rotors (3, 4) and associated with a shutter unit (17) suited to open and close the through opening (14).