Pump Device

Abstract

A centrifugal pump includes a pump body that defines a partition between a rotor chamber and a pump chamber, a motor case that forms the rotor chamber together with the pump body, a pump cover that forms the pump chamber together with the pump body, and a bearing that rotatably supports a rotor shaft of a rotor with respect to the pump body. The pump body includes a boss part that projects from a partition wall toward the rotor chamber and rotatably supports the bearing. A projection part projects from a lateral section of the boss part. The projection part has an inclined surface section inclined radially inward toward the leading end side of the boss part. The boss part has a connection hole that extends from the rotor chamber to the pump chamber. A rotor chamber side opening end portion of the connection hole opens to the inclined surface section.

1 . A pump device, comprising:
 a rotor chamber and a rotor rotatably disposed in the rotor chamber;   a pump chamber and an impeller rotatably disposed in the rotor chamber, wherein the impeller is coupled to the rotor and is configured to rotate with the rotor;   a partition wall defining a partition between the rotor chamber and the pump chamber;   a motor case that forms the rotor chamber together with the partition wall;   a pump cover that forms the pump chamber together with the partition wall; and   a bearing that rotatably supports a rotor shaft of the rotor with respect to the partition wall;   wherein:   a boss part projects from the partition wall toward the rotor chamber and supports the bearing;   a projection part extends from a lateral section of the boss part, the projection part having an inclined surface section inclined radially inward toward a leading end side of the boss part;   the boss part has formed therein a connection hole that extends from the rotor chamber to the pump chamber; and   a rotor chamber side opening end of the connection hole opens along the inclined surface section.   
     
     
         2 . The pump device according to  claim 1 , wherein the projection part has a conical shape or a polygonal pyramid shape formed concentrically with the boss portion. 
     
     
         3 . The pump device according to  claim 1 , wherein a pump chamber side opening end of the connection hole is positioned radially nearer a hollow part of the boss part than the rotor chamber side opening end of the connection hole. 
     
     
         4 . The pump device according to  claim 1 , wherein:
 the partition wall is made of a material having a thermal conductivity greater than a thermal conductivity of a material of the motor case, and   a portion of the partition wall is exposed to the outside of the motor case.   
     
     
         5 . The pump device according to  claim 1 , wherein the pump device further comprises:
 a first positioning portion for concentrically arranging the partition wall and the pump cover; and   a second positioning portion for concentrically arranging the partition wall and the motor case.   
     
     
         6 . The pump device according to  claim 1 , wherein:
 the pump device includes a first sealing member for face-sealing the partition wall and the pump cover, and   the pump device includes a second sealing member for face-sealing the partition wall and the motor case.   
     
     
         7 . The pump device according to  claim 1 , wherein the pump cover and the motor case are fastened together with the partition wall sandwiched therebetween. 
     
     
         8 . The pump device according to  claim 1 , wherein the connection hole extends in a direction oriented perpendicular to the inclined surface section. 
     
     
         9 . The pump device according to  claim 1 , wherein the connection hole extends in a direction non-parallel to a central axis of the rotor shaft.