Injectible two-stage compression rotary compressor

Abstract

An injectable two-stage compression rotary compressor includes a compressor housing; a low-stage compressing section provided in the compressor house; a high-stage compressing section provided near the low-stage compressing section; a motor for driving the low-stage compressing section and the high-stage compressing section; an accumulator held at an outer side portion of the compressor housing; a low-pressure connecting pipe connecting the accumulator and the low-stage compressing section; an intermediate connecting pipe connecting the low-stage compressing section and the high-stage compressing section outside the compressor housing; and an intermediate suction pipe for introducing a medium pressure injection refrigerant into the intermediate connecting pipe. The intermediate suction pipe is connected to the intermediate connecting pipe so that an outlet of the intermediate suction pipe faces in a flowing direction of a medium pressure gas refrigerant in the intermediate connecting pipe.

1 . An injectable two-stage compression rotary compressor used for a heat pump system utilizing an injection refrigerating cycle, the compressor comprising:
 a sealed cylindrical compressor housing in which first, second, and third communication holes are sequentially provided apart in an axial direction on an outer peripheral wall thereof;   a low-stage compressing section provided within the compressor housing with one end of a low-stage suction pipe connected to a low-stage suction hole through the second communication hole and one end of a low-stage discharge pipe connected to a low-stage muffler discharge hole through the first communication hole;   a high-stage compressing section provided near the low-stage compressing section within the compressor housing with one end of a high-stage suction pipe connected to a high-stage suction hole through the third communication hole and a high-stage muffler discharge hole communicating with an inside of the compressor housing;   a motor for driving the low-stage compressing section and the high-stage compressing section;   a sealed cylindrical accumulator held at an outer side portion of the compressor housing;   a low-pressure connecting pipe connecting a bottom communication hole of the accumulator and the other end of the low-stage suction pipe;   an intermediate connecting pipe connecting the other end of the low-stage discharge pipe and the other end of the high-stage suction pipe; and   an intermediate suction pipe for introducing a medium pressure injection refrigerant into the intermediate connecting pipe, the medium pressure injection refrigerant being a wet refrigerant of the injection refrigerating cycle side,   wherein the intermediate suction pipe is connected to the intermediate connecting pipe so that an outlet of the intermediate suction pipe faces in a flowing direction of a medium pressure gas refrigerant in the intermediate connecting pipe.   
   
   
       2 . The injectable two-stage compression rotary compressor according to  claim 1 ,
 wherein the second and third communication holes are provided in substantially the same circumferential position of the compressor housing,   the first communication hole is provided in a different circumferential position from the second and third communication holes,   the accumulator is held in substantially the same circumferential position as the second and third communication holes, and   the low-pressure connecting pipe and the intermediate connecting pipe, each being bent in a two-dimensional manner, are provided so that interference between the low-pressure connecting pipe and the intermediate connecting pipe is avoided.   
   
   
       3 . The injectable two-stage compression rotary compressor according to  claim 1 ,
 wherein the first and third communication holes are provided in substantially the same circumferential position of the compressor housing,   the second communication hole is provided in a different circumferential position from the first and third communication holes,   the accumulator is held in substantially the same circumferential position as the second communication hole, and   the low-pressure connecting pipe and the intermediate connecting pipe, each being bent in a two-dimensional manner, are provided so that interference between the low-pressure connecting pipe and the intermediate connecting pipe is avoided.   
   
   
       4 . An injectable two-stage compression rotary compressor according to  claim 1 , adapted to variable rotational speed drive.