| 摘要 |
PCT No. PCT/SE89/00299 Sec. 371 Date Nov. 27, 1990 Sec. 102(e) Date Nov. 27, 1990 PCT Filed May 29, 1989 PCT Pub. No. WO89/12752 PCT Pub. Date Dec. 28, 1989.The rotary positive displacement compressor has an intermediate port (42) for fluid from an intermediate pressure channel (30) and has a bleed port (44) for recirculation of partly compressed fluid through a return channel (32). It is suggested to provide the compressor with valve means (36), selectively adjustable between two end positions. In a first end position it opens up a direct communication between these channels (30, 32) and opens the bleed port (44), whereby fluid flows directly from the intermediate pressure channel (30) to the return channel (32) simultaneously as fluid within the working space of the compressor flows to the return channel (32) through the intermediate port (42) as well as through the bleed port (44). In a second end position the bleed port (44) is closed and said direct communication is blocked. The disclosure also relates to a refrigeration plant comprising such a compressor. |
