Hinge mechanism for variable displacement compressor

Abstract

By changing the inclination of a cam plate, the stroke of a piston is changed to change the discharge displacement a of compressor. A hinge mechanism is positioned between a rotating support and the cam plate. The hinge mechanism includes a guide pin, and the guide pin transfers the rotational motion of the rotating support to the cam plate and permits inclination of the cam plate. At least a part of the guide pin is hollow.

1 . A variable displacement compressor comprising: 
 a housing including a cylinder bore;    a piston accommodated in the cylinder bore;    a drive shaft supported by the housing;    a rotating support integrally fixed to the drive shaft;    a cam plate connected to the piston for converting rotational motion of the drive shaft to reciprocation of the piston, wherein the cam plate inclines with respect to the drive shaft, and wherein the stroke of the piston changes to vary the discharge displacement of the compressor when the inclination of the cam plate changes; and    a hinge mechanism positioned between the rotating support and the cam plate, wherein the hinge mechanism includes a guide pin for transferring rotation of the rotating support to the cam plate and for permitting the inclination of the cam plate, wherein a part of the guide pin is hollow.    
     
     
         2 . The compressor according to    claim 1   , wherein the hinge mechanism includes a supporting arm extending from the rotating support toward the cam plate and a guide portion provided in the support arm, the guide pin comprising: 
 a shaft portion, which is fixed to the cam plate, and a spherical portion, which has a larger diameter than the shaft portion and is provided on the shaft portion, wherein the spherical portion engages the guide portion, and at least a part of the spherical portion is hollow.    
     
     
         3 . The compressor according to    claim 2   , wherein the guide pin has a hollow chamber that is open on the outer periphery of the spherical portion, wherein the hollow chamber extends substantially to the center of the spherical portion.  
     
     
         4 . The compressor according to    claim 2   , wherein the guide pin has a hollow chamber that is open on the outer periphery of the spherical portion, wherein the hollow chamber extends to the shaft portion.  
     
     
         5 . The compressor according to    claim 2   , wherein a part of the shaft portion is embedded in the cam plate, and a part of the shaft portion is exposed from the cam plate, and wherein the guide pin has a hollow chamber that is open on the outer surface of the spherical portion, wherein the hollow chamber extends within the entire exposed portion of the shaft portion.  
     
     
         6 . The compressor according to    claim 1   , wherein the hinge mechanism comprises: 
 a swing arm extending from the cam plate toward the rotating support;    a supporting arm on the rotating support;    a guide hole formed in one of the swing arm and the supporting arm; and    a mounting hole formed in the other of the swing arm and the supporting arm, wherein the guide pin is located within the guide hole and the mounting hole.    
     
     
         7 . The compressor according to    claim 6   , wherein the guide hole is formed in the supporting arm and the mounting hole is formed in the swing arm.  
     
     
         8 . The compressor according to    claim 7   , wherein the swing arm is a first swing arm and the mounting hole is a first mounting hole, and the compressor further comprises a second swing arm and a corresponding second mounting hole, the first and second swing arms being arranged on opposite sides of the supporting arm, wherein the first mounting hole is coaxial with the second mounting hole, and end portions of the pin, which extend between the swing arms and the supporting arm, are solid.  
     
     
         9 . The compressor according to    claim 1   , wherein the guide pin is manufactured by forging.  
     
     
         10 . The compressor according to    claim 2   , wherein the distal end portion of the spherical portion is truncated.  
     
     
         11 . A guide pin used in a compressor, the compressor comprising: 
 a housing including a cylinder bore;    a piston accommodated in the cylinder bore;    a drive shaft supported by the housing;    a rotating support integrally fixed to the drive shaft;    a cam plate connected to the piston for converting the rotational motion of the drive shaft to reciprocation of the piston, wherein the cam plate inclines with respect to the drive shaft, and wherein the stroke of the piston changes to vary the discharge displacement of the compressor when the inclination of the cam plate changes;    a hinge mechanism positioned between the rotating support and the cam plate, wherein the hinge mechanism includes a guide pin for transferring rotation of the rotating support to the cam plate and for permitting the inclination of the cam plate, wherein a part of the guide pin is hollow.    
     
     
         12 . The guide pin according to    claim 11   , wherein the hinge mechanism includes a supporting arm extending from the rotating support toward the cam plate and a guide portion provided in the support arm, the guide pin comprising: 
 a shaft portion, which is fixed to the cam plate, and a spherical portion, which has a larger diameter than the shaft portion and is provided on the shaft portion, wherein the spherical portion engages the guide portion, and at least a part of the spherical portion is hollow.    
     
     
         13 . The guide pin according to    claim 12   , wherein the guide pin has a hollow chamber that is open on the outer periphery of the spherical portion, wherein the hollow chamber extends substantially to the center of the spherical portion.  
     
     
         14 . The guide pin according to    claim 12   , wherein the guide pin has a hollow chamber that is open on the outer periphery of the spherical portion, wherein the hollow chamber extends to the shaft portion.  
     
     
         15 . The guide pin according to    claim 12   , wherein a part of the shaft portion is embedded in the cam plate, and a part of the shaft portion is exposed from the cam plate, and wherein the guide pin has a hollow chamber that is open on the outer surface of the spherical portion, wherein the hollow chamber extends within the entire exposed portion of the shaft portion.