Compressor

Abstract

A compressor includes a housing, a rotary shaft, a bearing, a seal, a shaft seal chamber, a first passage, a second passage and the fluid passage. The first passage connects a crank chamber to the shaft seal chamber The second passage is formed between a lug plate fixed to the rotary shaft and the housing so as to connect the bearing to the crank chamber. The partition is provided in the shaft seal chamber for dividing the shaft seal chamber into a seal-side chamber and a bearing-side chamber. The first passage is in communication with the seal-side chamber of the shaft seal chamber. The fluid passage for accumulating the lubricating oil and for communicating the first passage and the second passage is formed radially inward of an inner circumferential surface of the shaft seal chamber.

1 . A compressor comprising: 
 a housing defining a crank chamber;    a rotary shaft at least one end of which extends out from the housing;    a bearing provided in the housing for rotatably supporting the rotary shaft;    a seal provided on the rotary shaft on an axially outer side of the bearing for preventing refrigerant gas from leaking out of the housing along the rotary shaft;    a shaft seal chamber defined by the seal, the bearing, the housing and the rotary shaft;    a first passage which connects the crank chamber to the shaft seal chamber so that the refrigerant gas containing therein lubricating oil in the crank chamber is drawn into the shaft seal chamber;    a second passage formed between a lug plate fixed to the rotary shaft and the housing so as to connect the bearing to the crank chamber; and    a fluid passage for accumulating the lubricating oil and for communicating with the first passage and the second passage, the fluid passage being formed radially inward of an inner circumferential surface of the shaft seal chamber.    
   
   
       2 . The compressor according to  claim 1 , further comprising: 
 a partition provided in the shaft seal chamber for dividing the shaft seal chamber into a seal-side chamber and a bearing-side chamber;    wherein the first passage is in communication with the seal-side chamber of the shaft seal chamber, the partition having the fluid passage through which the refrigerant gas is drawn from the seal-side chamber of the shaft seal chamber to the bearing-side chamber of the shaft seal chamber which is in communication with the second passage through the bearing.    
   
   
       3 . The compressor according to  claim 2 , wherein the fluid passage is formed between an inner circumferential surface of the partition and an outer circumferential surface of the rotary shaft which faces the inner circumferential surface.  
   
   
       4 . The compressor according to  claim 2 , wherein the fluid passage is a hole that extends through the partition.  
   
   
       5 . The compressor according to  claim 2 , wherein the rotary shaft includes a third passage which connects the bearing-side chamber of the shaft seal chamber to a discharge pressure region thereby to supply the refrigerant gas in the discharge pressure region to the bearing-side chamber to be in contact with the partition.  
   
   
       6 . The compressor according to  claim 2 , wherein the rotary shaft includes a fourth passage which connects the bearing-side chamber of the shaft seal chamber to the second passage thereby to supply the refrigerant gas on the bearing-side chamber of the shaft seal chamber to the second passage.  
   
   
       7 . The compressor according to  claim 1 , wherein cross sectional area of the fluid passage is smaller than that of the first passage.  
   
   
       8 . The compressor according to  claim 1 , wherein the bearing is a plain bearing, the refrigerant gas in the shaft seal chamber being drawn into the second passage through the fluid passage between an inner circumferential surface of the plain bearing and an outer circumferential surface of the rotary shaft.  
   
   
       9 . A compressor comprising: 
 a housing defining a crank chamber;    a rotary shaft at least one end of which extends out from the housing;    a bearing provided in the housing for rotatably supporting the rotary shaft;    a seal provided on the rotary shaft on an axially outer side of the bearing for preventing refrigerant gas from leaking out of the housing along the rotary shaft;    a shaft seal chamber defined by the seal, the bearing, the housing and the rotary shaft;    a first passage which connects the crank chamber to the shaft seal chamber so that the refrigerant gas containing therein lubricating oil in the crank chamber is drawn into the shaft seal chamber; and    a partition provided in the shaft seal chamber for dividing the shaft seal chamber into a seal-side chamber and a bearing-side chamber;    wherein the rotary shaft includes a fifth passage which connects the seal-side chamber of the shaft seal chamber to a suction pressure region and which has a throttle whose cross sectional area is smaller than that of the first passage.