Magnetic coupling pump

Abstract

A magnetic coupling pump according to the present invention has a housing including a pump chamber a motor chamber. The rotor includes a plurality of impellers projected from top face of a substantially disc-shaped main body of the rotor to be located in the pump chamber, and a substantially cylindrical magnet section projected from back face of the main body to be located in the motor chamber. The rotor is located in engine coolant, and is driven by a stator located inward of the magnet section in the motor chamber for sucking coolant from an inlet port and exhausting it from an outlet port. The pump is provided along an inner circumference of the stator with a cavity communicating with passages of fluid along an inner circumference of the magnet section and the back face of the main body of the magnet section. The cavity admits the coolant. The pump according to the present invention is able to prevent heat-up in the inner circumferential part of the stator.

What is claimed is:  
     
         1 . A magnetic coupling pump for sucking fluid from an inlet port and exhausting the fluid from an outlet port, the pump comprising a housing and a rotor, 
 the housing including a pump chamber having the inlet and outlet ports of fluid and a motor chamber,    the rotor including: 
 a plurality of impellers projected from top face of a substantially disc-shaped main body of the rotor to be located in the pump chamber; and  
 a magnet section projected from back face of the main body to be located in the motor chamber, the magnet section having a substantially cylindrical shape,  
   the rotor being located in the fluid and driven by a rotating magnetic field generated by a stator located inward of the magnet section in the motor chamber, wherein    a cavity is located along an inner circumference of the stator, the cavity communicating with passages of fluid along an inner circumference of the magnet section and the back face of the main body of the magnet section.    
     
     
         2 . The magnetic coupling pump according to  claim 1 , wherein: 
 the main body of the rotor includes a plurality of through holes in the vicinity of an inner circumferential part of the stator, the through holes being through from the top face to the back of the main body.    
     
     
         3 . The magnetic coupling pump according to  claim 1 , wherein: 
 the rotor includes a shaft section projecting into the cavity; and    the shaft section is provided in the outer circumference thereof with a plurality of impellers for stirring the fluid.    
     
     
         4 . The magnetic coupling pump according to  claim 2 , wherein: 
 the rotor includes a shaft section projecting into the cavity; and    the shaft section is provided in the outer circumference thereof with a plurality of impellers for stirring the fluid.    
     
     
         5 . The magnetic coupling pump according to  claim 1 , wherein: 
 the rotor includes a shaft section projecting into the cavity; and    the shaft section internally includes a passage with apertures opening in the cavity and in a top face of the main body,    whereby the fluid in the cavity circulates to the top face side of the main body through the passage.    
     
     
         6 . The magnetic coupling pump according to  claim 2 , wherein: 
 the rotor includes a shaft section projecting into the cavity; and    the shaft section internally includes a passage with apertures opening in the cavity and in a top face of the main body,    whereby the fluid in the cavity circulates to the top face side of the main body through the passage.    
     
     
         7 . The magnetic coupling pump according to  claim 3 , wherein: 
 the shaft section internally includes a passage with apertures opening in the cavity and in a top face of the main body,    whereby the fluid in the cavity circulates to the top face side of the main body through the passage.    
     
     
         8 . The magnetic coupling pump according to  claim 1 , wherein the rotor is rotatably supported at two positions of a position proximate to the main body and at a position in the cavity.  
     
     
         9 . The magnetic coupling pump according to  claim 2 , wherein the rotor is rotatably supported at two positions of a position proximate to the main body and at a position in the cavity.  
     
     
         10 . The magnetic coupling pump according to  claim 3 , wherein the rotor is rotatably supported at two positions of a position proximate to the main body and at a position in the cavity.  
     
     
         11 . The magnetic coupling pump according to  claim 4 , wherein the rotor is rotatably supported at two positions of a position proximate to the main body and at a position in the cavity.