Oil Compensation In A Refrigeration Circuit

Abstract

The invention relates to a refrigeration circuit with at least two compressors, each compressor comprising at least one lubrication point and at least one oil pump having an outlet for providing oil to said lubrication point; wherein the outlet of the oil pump of at least one of the compressors is fluidly connected to the lubrication point of at least one different compressor.

1 . Refrigeration circuit with at least two compressors, each compressor comprising at least one lubrication point and at least one oil pump having an outlet for providing oil to said lubrication point;
 wherein the outlet of the oil pump of at least one of the compressors is fluidly connected to the lubrication point of at least one different compressor.   
     
     
         2 . Refrigeration circuit according to  claim 1 , wherein the outlet of the oil pump of each compressor is fluidly connected to the lubrication point of at least one different compressor. 
     
     
         3 . Refrigeration circuit according to  claim 1 , wherein the lubrication point of each compressor is fluidly connected to the oil pump of at least one different compressor. 
     
     
         4 . Refrigeration circuit according to  claim 1 , wherein the outlets of the oil pumps of all compressors are fluidly connected by a common oil compensation line. 
     
     
         5 . Refrigeration circuit according to  claim 4 , wherein the common oil compensation line is fluidly connected to the lubrication points of all the compressors. 
     
     
         6 . Refrigeration circuit according to  claim 1 , wherein the compressors comprise oil sumps and the oil pumps are configured for delivering oil from the oil sumps of the compressors to the lubrication points. 
     
     
         7 . Refrigeration circuit according to  claim 6 , wherein the oil sumps of the compressors are fluidly connected. 
     
     
         8 . Refrigeration circuit according to  claim 6 , wherein the oil sumps of the compressors are not fluidly connected. 
     
     
         9 . Refrigeration circuit according to  claim 1 , wherein at least one of the compressors comprises a variable speed drive. 
     
     
         10 . Refrigeration circuit according to  claim 1 , wherein there is at least one switchable valve arranged between the outlet of the oil pump of at least one of the compressors and at least one of the lubrications points. 
     
     
         11 . Refrigeration circuit according to  claim 4 , wherein there is at least one switchable valve arranged between the outlet of the oil pump of at least one of the compressors and the common oil compensation line. 
     
     
         12 . Refrigeration circuit according to  claim 10 , wherein the at least one switchable valve is a solenoid valve. 
     
     
         13 . Method of operating a refrigeration circuit comprising a least two compressors each of the compressors having at least one lubrication point and at least one oil pump with at least one outlet, wherein the method comprises supplying oil from the outlet of one of the oil pumps to the lubrication point of at least one other compressor. 
     
     
         14 . Method of  claim 13  further comprising to supply oil from one of the oil pumps to the lubrication points of all compressors. 
     
     
         15 . Method of  claim 13  further comprising to supply oil from the oil pumps of all compressors to the lubrications points of all compressors. 
     
     
         16 . Method of  claim 13  further comprising delivering the oil through a common oil compensation line fluidly connecting the outlets of the oil pumps of the compressors. 
     
     
         17 . Method of  claim 16  further comprising actuating at least one switchable valve arranged between the outlet of the oil pump of one of the compressors and the common oil compensation line. 
     
     
         18 . Method of  claim 13  further comprising delivering oil from an oil sump formed in at least one of the compressors. 
     
     
         19 . Method of  claim 13  further comprising regulating the speed of at least one of the compressors.