Cylinder head for piston refrigeration compressor, compression unit including such cylinder head, and piston refrigeration compressor including said compression unit

Abstract

A cylinder head for a piston refrigeration compressor that includes at least a first part defining a cooling-gas suction chamber and at least a second part defining a cooling-gas discharge chamber, the first and second parts being distinct from each other, and the suction and discharge chambers each being intended to be brought into communication with a compression chamber provided in the compressor. The cylinder head includes thermal insulation means provided between the first and second parts, the thermal insulation means including an insulation chamber defined by the first and second parts.

1 . A cylinder head for piston refrigeration compressor, comprising at least a first part defining a cooling-gas suction chamber and at least a second part defining a cooling-gas discharge chamber, the first and second parts being distinct from each other, the suction and discharge chambers each being designed to be brought into communication with a compression chamber provided in the compressor, comprising thermal isolation means situated between the first and second parts, the thermal isolation means including an isolation chamber defined by the first and second parts wherein one of the first and second parts comprises a tubular portion and wherein the other part comprises a through passage, the tubular portion being arranged to be inserted into the through passage so as to define the isolation chamber between the outer wall of the tubular portion and the inner wall of the through passage. 
     
     
         2 . The cylinder head of  claim 1 , wherein the isolation chamber includes a volume of air at atmospheric pressure, a volume of cooling gas, such as CO 2 , at low or high pressure, a thermally isolating material, or a combination of these different elements. 
     
     
         3 . The cylinder head of  claim 1 , wherein the tubular portion has a groove extending over its entire periphery. 
     
     
         4 . The cylinder head of  claim 1 , wherein the part comprising the through passage has a return turned toward the inside of the through passage, the return being arranged to cooperate with the tubular portion. 
     
     
         5 . The cylinder head of  claim 4 , wherein the return extends over the entire circumference of the through passage. 
     
     
         6 . The cylinder head of  claim 4 , wherein a gasket is situated between the return and the tubular portion. 
     
     
         7 . The cylinder head of  claim 4 , wherein the return and the tubular portion define a groove designed to be filled with cooling gas under operating conditions of the piston refrigeration compressor. 
     
     
         8 . The cylinder head of  claim 1 , wherein the isolation chamber is essentially annular. 
     
     
         9 . A compression unit for piston refrigeration compressor, comprising a valve plate and a cylinder block, wherein it comprises a cylinder head according to  claim 1 . 
     
     
         10 . A piston refrigeration compressor comprising a compression unit according to  claim 9 .