Compressor

Abstract

A compressor includes a housing, a rotary shaft, a bearing, a seal, a shaft seal chamber, a lug plate, a thrust bearing, a first passage for connecting the crank chamber to the shaft seal chamber, a second passage provided in the housing for connecting the crank chamber to the shaft seal chamber, a third passage provided in the rotary shaft for connecting the shaft seal chamber to a discharge pressure region of the compressor, a partition provided in the shaft seal chamber for dividing the shaft seal chamber into a seal-side chamber and a bearing-side chamber and a clearance formed through the partition for drawing the refrigerant gas from the seal-side chamber of the shaft seal chamber to the bearing-side chamber of the shaft seal chamber, the clearance being formed radially inward of the inner circumferential surface of the shaft seal chamber.

1 . A compressor comprising:
 a housing defining therein a crank chamber;   a rotary shaft having opposite ends at least one end of which extends out of the housing;   a bearing provided in the housing for rotatably supporting the rotary shaft;   a seal provided on the rotary shaft at a position which is 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 lug plate fixed to the rotary shaft;   a thrust bearing for axially supporting the lug plate such that the lug plate is rotatable relative to the housing;   a first passage provided in the housing for connecting 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 provided in the housing for connecting the crank chamber to the shaft seal chamber so that the refrigerant gas in the shaft seal chamber is drawn into the crank chamber;   a third passage provided in the rotary shaft for connecting the shaft seal chamber to a discharge pressure region of the compressor so that the refrigerant gas in the discharge pressure region is drawn into the shaft seal chamber;   a partition provided in the shaft seal chamber for dividing the shaft seal chamber into a seal-side chamber and a bearing-side chamber; and   a clearance formed through the partition for drawing the refrigerant gas from the seal-side chamber of the shaft seal chamber to the bearing-side chamber of the shaft seal chamber, the clearance being formed radially inward of the inner circumferential surface of the shaft seal chamber,   wherein the first passage is in communication with the seal-side chamber of the shaft seal chamber,   wherein the second passage is in communication with the bearing-side chamber of the shaft seal chamber,   wherein the third passage is in communication with the bearing-side chamber of the shaft seal chamber,   wherein the refrigerant gas in the discharge pressure region of the compressor is flowed through the third passage into the bearing-side chamber of the shaft seal chamber such that the refrigerant gas is brought into contact with the partition, and   wherein the refrigerant gas in the bearing-side chamber of the shaft seal chamber is flowed through the second passage into the crank chamber.   
   
   
       2 . The compressor according to  claim 1 , further comprising:
 a space defined by the housing, the lug plate and the thrust bearing; and   a fourth passage provided above the shaft seal chamber as seen from the gravity direction in the housing for connecting the space to the crank chamber.   
   
   
       3 . The compressor according to  claim 1 , wherein the second passage is provided below the shaft seal chamber as seen from the gravity direction. 
   
   
       4 . The compressor according to  claim 1 , wherein a recess is formed in the circumferential direction of the rotary shaft at one end of the fourth passage which is in communication with the space. 
   
   
       5 . The compressor according to  claim 1 , wherein the clearance is formed between the inner circumferential surface of the partition and the outer circumferential surface of the drive shaft which faces the inner circumferential surface. 
   
   
       6 . The compressor according to  claim 1 , wherein the clearance has a cross section whose area is smaller than that of the first passage. 
   
   
       7 . The compressor according to  claim 1 , wherein the third passage is formed obliquely in facing relation to the partition. 
   
   
       8 . The compressor according to  claim 1 , wherein the fourth passage is formed extending along the gravity direction.