Piston assembly of cooler

Abstract

There is provided a piston assembly configured to include: a hollow cylinder-shaped magnet sleeve having a magnet(s) bonded on external circumferential surface thereof; a hollow cylinder-shaped piston inserted into a hollow space of the magnet sleeve; and a hollow disc-shaped ring fixed to the piston by a shrink fitting process, and welded to the magnet sleeve which is made of the same material as the ring so as to obtain a configuration of the piston assembly in which the magnet sleeve and the piston are coupled to each other.

1 . A piston assembly comprising: 
 a hollow cylinder-shaped magnet sleeve having a magnet(s) bonded on external circumferential surface thereof;    a hollow cylinder-shaped piston inserted into a hollow space of the magnet sleeve; and    a hollow disc-shaped ring fixed to the piston by a shrink fitting process, and welded to the magnet sleeve which is made of the same material as the ring so as to obtain a configuration of the piston assembly in which the magnet sleeve and the piston are coupled to each other.    
   
   
       2 . The piston assembly according to  claim 1 , wherein the ring is inserted between the piston and the magnet sleeve by the shrink fitting process.  
   
   
       3 . The piston assembly according to  claim 1 , wherein the magnet sleeve and the ring are welded by a friction welding method.  
   
   
       4 . The piston assembly according to  claim 1 , wherein the magnet sleeve and the ring are welded by an electric resistance welding method.  
   
   
       5 . The piston assembly according to  claim 1 , wherein the magnet sleeve and the ring are welded by a plasma welding method.  
   
   
       6 . The piston assembly according to  claim 1 , wherein the magnet sleeve and the ring are welded by a laser welding method.  
   
   
       7 . A piston assembly comprising: 
 a hollow cylinder-shaped magnet sleeve having a bent portion inwardly bent at one end of a hollow space thereof, and a magnet bonded on an external circumferential surface thereof;    a hollow cylinder-shaped piston insertedly equipped in the hollow space of the magnet sleeve and having a fixing member-inserting hole formed in a flange part thereof; and    a fixing member fusion-fixed to the magnet sleeve by an applied electric current, and functioning as a solvent to fix the bent portion of the magnet sleeve and the flange part of the piston to each other.    
   
   
       8 . The piston assembly according to  claim 7 , wherein the fixing member is made of a material which is possibly fused by the applied electric current.  
   
   
       9 . The piston assembly according to  claim 7 , wherein the fixing member is entirely rivet-shaped.  
   
   
       10 . The piston assembly according to  claim 7 , wherein the fixing member is coupled using an electric resistance welding method to weld the bent portion of the magnet sleeve and the flange part of the piston.  
   
   
       11 . A piston assembly comprising: 
 a hollow cylinder-shaped magnet sleeve having a bent portion inwardly bent at one end of a hollow space thereof, and a magnet(s) bonded on an external circumferential surface thereof, the bent portion having a fixing member-inserting hole;    a hollow cylinder-shaped piston insertedly equipped in the hollow space of the magnet sleeve and having a fixing member-inserting hole formed in a flange part thereof; and    a fixing member fusion-fixed to the magnet sleeve by an applied electric current, and functioning as a solvent to fix the bent portion of the magnet sleeve and the flange part of the piston to each other.    
   
   
       12 . The piston assembly according to  claim 11 , wherein the fixing member is made of a material which is possibly fused by the applied electric current.  
   
   
       13 . The piston assembly according to  claim 11 , wherein the fixing member is entirely rivet-shaped.  
   
   
       14 . The piston assembly according to  claim 11 , wherein the fixing member is fixed using an electric resistance welding method to weld the bent portion of the magnet sleeve and the flange part of the piston.