Lubricating structure in piston type compressor

Abstract

A lubricating structure in a piston type compressor has a housing. a rotary shaft, a rotary valve and a shaft seal device. The housing defines a seal chamber, a plurality of cylinder bores and a suction pressure region. The rotary shaft is rotatably supported by the housing and includes a lubricating passage that interconnects the seal chamber and the suction pressure region. The rotary valve is connected to the rotary shaft and includes an introducing passage. The rotary shaft further includes a supply passage that interconnects the introducing passage and the suction pressure region for introducing fluid into the cylinder bores. The shaft seal device is located in the seal chamber and is located between the housing and the rotary shaft for preventing the fluid from leaking along a circumferential surface of the rotary shaft from the housing.

What is claimed is:  
     
         1 . A lubricating structure in a piston type compressor, comprising: 
 a housing defining a seal chamber, a plurality of cylinder bores and a suction pressure region;    a rotary shaft rotatably supported by the housing, the rotary shaft including a lubricating passage that interconnects the seal chamber and the suction pressure region;    a rotary valve connected to the rotary shaft, the rotary valve including an introducing passage, the rotary shaft including a supply passage that interconnects the introducing passage and the suction pressure region for introducing the fluid into the cylinder bores; and    a shaft seal device located in the seal chamber, the shaft seal device being located between the housing and the rotary shaft for preventing fluid from leaking along a circumferential surface of the rotary shaft from the housing.    
     
     
         2 . The lubricating structure according to  claim 1 , wherein the rotary valve is integrated with the rotary shaft, the introducing passage being formed in the rotary shaft.  
     
     
         3 . The lubricating structure according to  claim 1 , wherein the lubricating passage includes the supply passage and a communication hole formed in the circumferential surface of the rotary shaft.  
     
     
         4 . The lubricating structure according to  claim 3 , wherein the lubricating passage includes a plurality of the communication holes.  
     
     
         5 . The lubricating structure according to  claim 3 , wherein the communication hole is located near the introducing passage.  
     
     
         6 . A rotary shaft for use in a piston type compressor that has a housing including a seal chamber, a cylinder bore and a suction pressure region, and a shaft seal device located in the seal chamber, the rotary shaft comprising: 
 a supply passage communicating with the suction pressure region;    an introducing passage communicating with the supply passage for introducing fluid into the cylinder bore; and    a lubricating passage interconnecting the seal chamber and the suction pressure region for introducing the fluid with lubricant in the suction pressure region into the seal chamber, the part of lubricant staying in the seal chamber.    
     
     
         7 . The rotary shaft according to  claim 6 , wherein the lubricating passage includes the supply passage and a communication hole formed in a circumferential surface of the rotary shaft.  
     
     
         8 . The rotary shaft according to  claim 7 , wherein the communication hole is located near the introducing passage.  
     
     
         9 . A piston type compressor connected to an external refrigerant circuit, the compressor comprising: 
 a housing defining a seal chamber, a cam chamber, a plurality of cylinder bores and a suction pressure region;    a rotary shaft rotatably supported by the housing, the rotary shaft including a first lubricating passage that interconnects the suction pressure region and the seal chamber for introducing fluid with lubricant in the suction pressure region into the seal chamber, the part of lubricant staying in the seal chamber;    a cam located in the cam chamber, the cam being operatively connected to the rotary shaft;    a piston located in each of the cylinder bores, the piston engaging the cam to reciprocate in accordance with rotation of the rotary shaft through the cam;    a rotary valve connected to the rotary shaft, the rotary valve including an introducing passage, the rotary shaft including a supply passage that interconnects the introducing passage and the suction pressure region for introducing the fluid into the cylinder bore; and    a shaft seal device located in the seal chamber, the shaft seal device being located between the housing and the rotary shaft for preventing the fluid from leaking along a circumferential surface of the rotary shaft from the housing.    
     
     
         10 . The piston type compressor according to  claim 9 , wherein the supply passage interconnects the cam chamber and the suction pressure region for introducing the fluid into the cam chamber, the introducing passage communicating with the cam chamber for introducing the fluid into the cylinder bore.  
     
     
         11 . The piston type compressor according to  claim 9 , wherein the first lubricating passage includes the supply passage and a communication hole formed in the circumferential surface of the rotary shaft, the communication hole communicating with the supply passage at a first communication opening.  
     
     
         12 . The piston type compressor according to  claim 11 , the supply passage communicating with the introducing passage at a second communication opening.  
     
     
         13 . The piston type compressor according to  claim 12 , wherein the second communication opening is located near the first communication opening.  
     
     
         14 . The piston type compressor according to  claim 9 , wherein the housing includes a second lubricating passage that interconnects the seal chamber and the cam chamber.  
     
     
         15 . The piston type compressor according to  claim 14 , wherein the housing includes a cylinder block defining the cylinder bores, the cam chamber being defined in the cylinder block, the second lubricating passage extending through the cylinder block.  
     
     
         16 . The piston type compressor according to  claim 14 , wherein the housing includes: 
 a housing element defining the seal chamber; and    a cylinder block fastened to the housing element by a bolt, the housing element and the cylinder block defining a bolt hole, the bolt being inserted through the bolt hole, the second lubricating passage at least partially including: 
 a clearance formed between a circumferential surface of the bolt and an inner circumferential surface of the bolt hole; and  
 a groove recessed in an end surface of the cylinder block that faces the housing element, the groove communicating with the bolt hole.  
   
     
     
         17 . The piston type compressor according to  claim 14 , wherein the housing includes: 
 a housing element defining the seal chamber; and    a cylinder block fastened to the housing element by a bolt, the housing element and the cylinder block defining a bolt hole, the bolt being inserted through the bolt hole, wherein the piston type compressor further comprising: 
 a valve port plate interposed between the housing element and the cylinder block, the second lubricating passage at least partially including: 
 a clearance formed between a circumferential surface of the bolt and an inner circumferential surface of the bolt hole; and  
 a groove recessed in the valve port plate, the groove communicating with the bolt hole.  
 
   
     
     
         18 . The piston type compressor according to  claim 9 , wherein the suction pressure region includes a suction chamber that communicates with the external refrigerant circuit.  
     
     
         19 . The piston type compressor according to  claim 9 , wherein the rotary valve is integrated with the rotary shaft.  
     
     
         20 . The piston type compressor according to  claim 9 , wherein the piston is a double-headed type.  
     
     
         21 . The piston type compressor according to  claim 9 , wherein the compressor is a fixed displacement type.  
     
     
         22 . A lubricating structure in a piston type compressor connected to an external refrigerant circuit, comprising: 
 a housing defining a seal chamber, a cam chamber, a plurality of cylinder bores and a suction pressure region;    a rotary shaft rotatably supported by the housing, the rotary shaft including a communication passage that interconnects the suction pressure region and the seal chamber;    a cam located in the cam chamber, the cam being operatively connected to the rotary shaft;    a piston located in each of the cylinder bores, the piston engaging the cam to reciprocate in accordance with rotation of the rotary shaft through the cam;    a rotary valve connected to the rotary shaft, the rotary valve including an introducing passage, the rotary shaft including a supply passage that interconnects the introducing passage and the suction pressure region for introducing the fluid into the cylinder bores;    a shaft seal device located in the seal chamber, the shaft seal device being located between the housing and the rotary shaft for preventing fluid from leaking along a circumferential surface of the rotary shaft from the housing; and    a lubricating passage interconnecting the cam chamber and the seal chamber.    
     
     
         23 . The lubricating structure according to  claim 22 , wherein the housing includes a cylinder block defining the cylinder bores, the cam chamber being defined in the cylinder block, the lubricating passage extending through the cylinder block.  
     
     
         24 . The lubricating structure according to  claim 22 , wherein the housing includes: 
 a housing element defining the seal chamber; and    a cylinder block fastened to the housing element by a bolt, the housing element and the cylinder block defining a bolt hole, the bolt being inserted through the bolt hole, the lubricating passage at least partially including: 
 a clearance formed between a circumferential surface of the bolt and an inner circumferential surface of the bolt hole; and  
 a groove recessed in an end surface of the cylinder block that faces the housing element, the groove communicating with the bolt hole.  
   
     
     
         25 . The lubricating structure according to  claim 22 , wherein the suction pressure region includes a suction chamber that communicates with the external refrigerant circuit.  
     
     
         26 . The lubricating structure according to  claim 22 , wherein the communication passage includes the supply passage and a communication hole formed in the circumferential surface of the rotary shaft.  
     
     
         27 . The lubricating structure according to  claim 22 , wherein the rotary valve is integrated with the rotary shaft.  
     
     
         28 . The lubricating structure according to  claim 22 , wherein the piston is a double-headed type.  
     
     
         29 . The lubricating structure according to  claim 22 , wherein the compressor is a fixed displacement type.  
     
     
         30 . The lubricating structure according to  claim 22 , wherein the housing includes: 
 a housing element defining the seal chamber; and    a cylinder block fastened to the housing element by a bolt, the housing element and the cylinder block defining a bolt hole, the bolt being inserted through the bolt hole, wherein the lubricating structure further comprising: 
 a valve port plate interposed between the housing element and the cylinder block, the lubricating passage at least partially including: 
 a clearance formed between a circumferential surface of the bolt and an inner circumferential surface of the bolt hole; and  
 a groove recessed in the valve port plate, the groove communicating with the bolt hole.