Compressor having a mechanism for separating and recovering lubrication oil

Abstract

A compressor has a discharge passage, an oil separation mechanism, an oil supply passage, and a valve mechanism. The oil supply passage supplies the separated lubrication oil into an oil recovery region. The valve mechanism is formed in the oil supply passage and includes a valve chamber, a spool and an urging member. The spool separates the valve chamber into a first pressure sensing chamber and a second pressure sensing chamber. The amount of the lubrication oil supplied to the oil recovery region is adjusted in such a manner that as the pressure differential between the first and the second pressure sensing chambers increases, the spool slides in the valve chamber and the opening degree of the oil supply passage increases to the maximum and then decreases, and that when the compressor is stopped, the opening degree of the oil supply passage is minimized by the urging force of the urging member.

1 . A compressor comprising:
 an outlet for discharging refrigerant gas out from the compressor;   a discharge passage connected to the outlet, wherein the refrigerant gas is discharged through the discharge passage and the outlet;   an oil separation mechanism for separating lubrication oil from the refrigerant gas;   an oil supply passage supplying the separated lubrication oil into an oil recovery region;   a valve mechanism formed in the oil supply passage, wherein the valve mechanism includes a valve chamber, a spool and an urging member, wherein the spool separates the valve chamber into a first pressure sensing chamber and a second pressure sensing chamber;   wherein the amount of the lubrication oil supplied to the oil recovery region is adjusted in such a manner that as the pressure differential between the first pressure sensing chamber and the second pressure sensing chamber increases, the spool slides in the valve chamber and the opening degree of the oil supply passage increases to the maximum and then decreases, and that when the compressor is stopped, the opening degree of the oil supply passage is minimized by the urging force of the urging member.   
   
   
       2 . The compressor according to  claim 1 , wherein the first pressure sensing chamber is connected to a high pressure region and the second pressure sensing chamber is connected to a low pressure region. 
   
   
       3 . The compressor according to  claim 2 , wherein the high pressure region includes a discharge passage, and the low pressure region includes a suction chamber. 
   
   
       4 . The compressor according to  claim 1 , wherein the oil recovery region includes a suction chamber. 
   
   
       5 . The compressor according to  claim 1 , wherein the oil supply passage includes an oil passage which communicates the valve chamber to the oil recovery region, wherein an oil introduction hole is formed in the spool facing the first pressure sensing chamber so as to face a circumferential surface of the valve chamber at a side surface thereof, wherein the oil introduction hole overlaps an opening end of the oil passage formed in the circumferential surface of the valve chamber when the spool slides, so as to open the oil supply passage, wherein the opening degree of the oil supply passage is adjusted in accordance with an area where the oil introduction hole and the opening end of the oil passage overlap. 
   
   
       6 . The compressor according to  claim 1 , wherein a groove is formed on the valve chamber to be positioned so that the first pressure sensing chamber and the second pressure sensing chamber communicate through the groove when the spool slides so as to open the oil supply passage. 
   
   
       7 . The compressor according to  claim 1 , wherein the first pressure sensing chamber is connected to an upstream of the oil separation mechanism and the second pressure sensing chamber is connected to a downstream of the oil separation mechanism, wherein the spool is moved by the pressure differential between the upstream and the downstream of the oil separation mechanism. 
   
   
       8 . The compressor according to  claim 7 , wherein the discharge passage has a branching point connecting to the second pressure sensing chamber, and a check valve is formed between the branching point and the oil separation mechanism in the discharge passage. 
   
   
       9 . The compressor according to  claim 1 , wherein the oil separation chamber is integrally formed with the valve chamber. 
   
   
       10 . The compressor according to  claim 1 , wherein the urging member is a spring. 
   
   
       11 . The compressor according to  claim 1 , wherein the urging member is a pair of magnets to be formed to generate a repelling force with each other. 
   
   
       12 . A compressor comprising
 an outlet for discharging refrigerant gas out from the compressor;   a discharge passage connected to the outlet, wherein the refrigerant gas is discharged through the discharge passage and the outlet;   an oil separation mechanism for separating lubrication oil from the refrigerant gas;   an oil supply passage supplying the separated lubrication oil into an oil recovery region and including an oil passage;   a valve mechanism formed in the oil supply passage, wherein the valve mechanism includes a valve chamber, a spool and an urging member, wherein the spool separates the valve chamber into a first pressure sensing chamber and a second pressure sensing chamber, the spool being moved in the valve chamber in accordance with the pressure differential between the first pressure sensing chamber and the second pressure sensing chamber, wherein the spool includes an oil introduction hole facing the first pressure sensing chamber and a circumferential surface of the valve chamber;   wherein the oil passage communicates the valve chamber to the oil recovery region and has an opening end formed on the circumferential surface of the valve chamber, an opening degree of the oil supply passage being determined in accordance with a communicating area where the oil introduction hole facing the circumferential surface of the valve chamber and the opening end of the oil passage overlap;   wherein as the pressure differential increases, the spool is moved in the valve chamber against the urging member such that the oil introduction hole facing the circumferential surface of the valve chamber and the opening end of the oil passage begins to overlap, the communicating area becomes maximum and the oil introduction hole facing the circumferential surface of the valve chamber begins to pass through the opening end of the oil passage, so that the opening degree of the oil supply passage becomes maximum from minimum and then becomes smaller than the maximum, and wherein the opening degree of the oil supply passage is minimized by the urging member when the compressor is stopped.