Method And Equipment For Detecting Failure In Oil Film Formation Of Swash Plate Compressor

Abstract

A swash plate compressor is provided with first conducting means conductive to a shoe of a piston and second conducting means conductive to a swash plate, a voltage with a predetermined intensity is applied from the outside to each of the shoes and the swash plate by a voltage application circuit, and a voltage value of the voltage application circuit is measured by a voltage measuring instrument so that a failure in oil film formation between the shoe and the swash plate can be detected. Thus, there is no need to install precision equipment such as a sensor, a camera or a transmitter inside the compressor body, and the failure in oil film formation can be detected more surely with a simple structure.

1 . A method for detecting failure in oil film formation of a swash plate compressor comprising a plurality of cylinders provided with an interval to each other in the circumferential direction in a compressor body, a piston reciprocating in each cylinder, a swash plate slidably engaging with one end side of the piston, and a driving shaft for rotating the swash plate, in which the one end side of the piston is slidably engaged with the swash plate through a pair of shoes opposing each other with the swash plate between them, 
 wherein a voltage of a predetermined constant voltage power supply is applied through a voltage application circuit to conducting means for conducting electricity to the shoe of the piston and the swash plate; and    a voltage value of the voltage application circuit is measured so as to determine if a value of the measured voltage is equal to or larger than a predetermined reference value or not.    
   
   
       2 . Equipment for detecting failure in oil film formation of a swash plate compressor comprising a plurality of cylinders provided with an interval to each other in the circumferential direction in a compressor body, a piston reciprocating in each cylinder, a swash plate slidably engaging with one end side of the piston, and a driving shaft for rotating the swash plate, in which the one end side of the piston is slidably engaged with the swash plate through a pair of shoes opposing each other with the swash plate between them, comprising: 
 first conducting means for conducting electricity to the shoe of the piston;    second conducting means for conducting electricity to the swash plate;    a voltage application circuit connected from the outside to the first and the second conducting means for applying a voltage of a predetermined constant voltage power supply to the first and the second conducting means;    a voltage measuring instrument for measuring a voltage value of the voltage application circuit; and    a determining processor for determining if the value of the measured voltage of the voltage measuring instrument is equal to or larger than a predetermined reference value.    
   
   
       3 . The equipment for detecting failure in oil film formation of a swash plate compressor according to  claim 2 , further comprising: 
 a terminal provided on the outer face side of the compressor body and to which the voltage application circuit can be connected;    a conductive member provided on the side of the piston for conducting electricity to the terminal; and    a conductive contact member provided at the piston and slidably contacting the conductive member,    wherein the first conducting means is formed so that the terminal, the conductive member, the contact member, the piston and the shoe are sequentially conducted.    
   
   
       4 . The equipment for detecting failure in oil film formation of a swash plate compressor according to  claim 2 , wherein the second conducting means is formed so that the compressor body, the driving shaft and the swash plate are sequentially conducted.  
   
   
       5 . The equipment for detecting failure in oil film formation of a swash plate compressor according to  claim 2 , wherein the contact member is provided so that it is pressed into contact with the conductive member by a spring.  
   
   
       6 . The equipment for detecting failure in oil film formation of a swash plate compressor according to  claim 2 , wherein the conductive member and the contact member are provided on both sides in the width direction of the piston, respectively.  
   
   
       7 . The equipment for detecting failure in oil film formation of a swash plate compressor according to  claim 6 , wherein each of the conductive members is provided so as to regulate rotation of the piston in the circumferential direction.  
   
   
       8 . The equipment for detecting failure in oil film formation of a swash plate compressor according to  claim 2 , wherein a conductive elastic member having one end side fixed to the piston so that the other end is in contact with the shoe is provided at the piston.  
   
   
       9 . The equipment for detecting failure in oil film formation of a swash plate compressor according to  claim 2 , wherein the voltage measuring instrument measures a voltage value of a variable resistor provided at the voltage application circuit.  
   
   
       10 . The equipment for detecting failure in oil film formation of a swash plate compressor according to  claim 2 , wherein the swash plate is insulated from one of the shoes by an insulating member.  
   
   
       11 . Equipment for detecting failure in oil film formation of a swash plate compressor comprising a plurality of cylinders provided with an interval to each other in the circumferential direction in a compressor body, a piston reciprocating in each cylinder, a swash plate slidably engaging with one end side of the piston, and a driving shaft for rotating the swash plate, in which the one end side of the piston is slidably engaged with the swash plate through a pair of shoes opposing each other with the swash plate between them, comprising: 
 first conducting means for conducting electricity to the shoe of the piston;    second conducting means for conducting electricity to the swash plate;    a voltage application circuit connected from the outside to the first and the second conducting means for applying a voltage of a predetermined constant voltage power supply to the first and the second conducting means;    a voltage measuring instrument for measuring a voltage value of the voltage application circuit;    a determining processor for determining if the value of the measured voltage of the voltage measuring instrument is equal to or larger than a predetermined reference value;    a terminal provided on the outer face side of the compressor body and to which the voltage application circuit can be connected;    a conductive member provided on the side of the piston for conducting electricity to the terminal; and    a conductive contact member provided at the piston and slidably contacting the conductive member,    wherein the first conducting means is formed so that the terminal, the conductive member, the contact member, the piston and the shoe are sequentially conducted;    the second conducting means is formed so that the compressor body, the driving shaft and the swash plate are sequentially conducted;    the contact member is provided so that it is pressed into contact with the conductive member by a spring;    the conductive member and the contact member are provided on both sides in the width direction of the piston, respectively;    each of the conductive members is provided so as to regulate rotation of the piston in the circumferential direction;    a conductive elastic member having the other end side fixed to the piston so that one end is in contact with the shoe is provided at the piston;    the voltage measuring instrument is constructed to measure a voltage value of a variable resistor provided at the voltage application circuit; and    the swash plate is insulated from one of the shoes by an insulating member.