Variable displacement compressor

Abstract

A variable displacement compressor includes a housing, a rotary shaft, a bearing, a seal member, a shaft seal chamber, a discharge refrigerant passage and a partition. The partition is provided in the shaft seal chamber for partitioning the shaft seal chamber into a first seal chamber to which the discharge refrigerant passage is opened and a second seal chamber part of the periphery of which is formed by the bearing and the seal member. The partition is provided with a first guide passage through which refrigerant containing lubricating oil flowed from the discharge refrigerant passage into tho first seal chamber is substantially all supplied to the seal member of the second seal chamber.

1 . A variable displacement compressor comprising;
 a housing having a crank chamber;   a rotary shaft disposed in the crank chamber with at least one end thereof exposed outside the housing;   a bearing disposed in the housing for rotatably supporting the rotary shaft;   a seal member disposed in the housing at a position between the exposed end of the rotary shaft and the bearing for preventing refrigerant mixed with lubricating oil from leaking out of the housing along the rotary shaft;   a shaft seal chamber defined by the housing, the rotary shaft, the bearing and the seal member;   a discharge refrigerant passage formed in the rotary shaft, wherein the refrigerant flows into the shaft seal chamber through the discharge refrigerant passage; and   a partition provided in the shaft seal chamber for partitioning the shaft seal chamber into a first seal chamber to which the discharge refrigerant passage is opened and a second seal chamber part of the periphery of which is formed by the bearing and the seal member, wherein the partition is provided with a first guide passage through which the refrigerant flowed from the discharge refrigerant passage into the first seal chamber is substantially all supplied to the seal member of the second seal chamber.   
   
   
       2 . The variable displacement compressor according to  claim 1 , further comprising a lug plate fixed on the rotary shaft for rotation therewith, wherein the shaft seal chamber is defined by the housing, the rotary shaft, the lug plate, the bearing and the seal member. 
   
   
       3 . The variable displacement compressor according to  claim 2 , wherein the partition is provided on the lug plate. 
   
   
       4 . The variable displacement compressor according to  claim 1 , wherein the partition is provided on the rotary shaft. 
   
   
       5 . The variable displacement compressor according to  claim 1 , wherein the first guide passage is formed between the end of the partition and the outer surface of the rotary shaft. 
   
   
       6 . The variable displacement compressor according to  claim 5 , wherein the first guide passage is formed along the outer surface of the rotary shaft and toward the seal member. 
   
   
       7 . The variable displacement compressor according to  claim 1 , wherein the first seal chamber is defined between the partition and the rotary shaft so that a sectional area of the first seal chamber decreases from a position adjacent to the discharge refrigerant passage toward the first guide passage. 
   
   
       8 . The variable displacement compressor according to  claim 1 , wherein the partition is further provided with a second guide passage through which the refrigerant flowed through the first guide passage is allowed to flow along an outer circumferential surface of the seal member.