Swash plate-type compressors

Abstract

A swash plate-type compressor includes a housing having a cylinder block with a plurality of cylinder bores formed therethrough. The cylinder block encloses a crank chamber, a suction chamber, and a discharge chamber. The compressor also includes a drive shaft rotatably supported by the housing, a plurality of pistons positioned within a corresponding one of the cylinder bores, and a swash plate rotatably mounted on the drive shaft. The compressor further includes a discharge path formed between the crank chamber and the suction chamber. Moreover, the compressor includes a check valve positioned within the discharge path. The check valve is adapted to open the discharge path when a first pressure in the crank chamber is greater than a second pressure in the suction chamber and to close the discharge path when the first pressure is less than or equal to the second pressure. Consequently, a refrigerant within the crank chamber is discharged into the suction chamber when the first pressure is greater than the second pressure. Nevertheless, the refrigerant within the suction chamber is not discharged into the crank chamber when the first pressure is less than or equal to the second pressure.

What is claimed is:  
     
         1 . A swash plate-type compressor comprising: 
 a housing having a cylinder block with a plurality of cylinder bores formed therethrough, wherein the cylinder block encloses a crank chamber, a suction chamber, and a discharge chamber;    a drive shaft rotatably supported by the housing;    a plurality of pistons each of which is positioned within a corresponding one of the cylinder bores;    a swash plate rotatably mounted on the drive shaft;    a discharge path formed between the crank chamber and the suction chamber; and    a check valve positioned within the discharge path, wherein the check valve is adapted to open the discharge path when a first pressure in the crank chamber is greater than a second pressure in the suction chamber, and to close the discharge path when the first pressure is less than or equal to the second pressure, such that a refrigerant within the crank chamber is discharged into the suction chamber via the discharge path when the first pressure is greater than the second pressure.    
     
     
         2 . The swash plate-type compressor of  claim 1 , wherein the discharge path comprises a center bore formed in the cylinder block.  
     
     
         3 . The compressor of  claim 1 , wherein the check valve comprises: 
 a case having a substantially cylindrical shape and a bottom portion, wherein at least one first opening is formed through the bottom portion,    a valve seat adapted to close an open end of the case, wherein a second opening is formed through the valve seat;    a valve element positioned within the case and fixed to a biasing member; and    a plurality of supports extending from the bottom portion of the case.    
     
     
         4 . The compressor of  claim 1 , wherein the check valve comprises: 
 a penetration path formed through the check valve;    a valve seat having a substantially funnel-like shape and formed at an end of the penetration path; and    a valve element adapted to be received by the valve seat.    
     
     
         5 . The compressor of  claim 1 , wherein the check valve comprises: 
 a case having a substantially cylindrical shape and a bottom portion, wherein a first opening is formed through the bottom portion and at least one second opening is formed through a side wall of the case, and wherein there is a clearance between the side wall and an inner surface of the discharge path;    a cap adapted to close an opening of the case; and    a valve element positioned within the case and fixed to a biasing member.