Impeller and pump

Abstract

The present application relates an impeller and a pump. The impeller includes a shaft insertion hole, a fastening hole having a diameter smaller than a diameter of the shaft insertion hole, and a sleeve insertion hole having a diameter larger than a diameter of the shaft insertion hole.

What is claimed is: 
     
         1 . An impeller, comprising:
 a shaft insertion hole into which a main shaft of an electric motor can be inserted;   a fastening hole having a diameter smaller than a diameter of the shaft insertion hole, and into which a fastener fastened to the main shaft can be inserted; and   a sleeve insertion hole having a diameter larger than a diameter of the shaft insertion hole, and into which a shaft sleeve attached to the main shaft can be inserted,   wherein the sleeve insertion hole has a seal groove formed on an opposite surface of the shaft sleeve when the shaft sleeve is inserted into the sleeve insertion hole, and   wherein the shaft sleeve is arranged in a straight line between a main plate of the impeller and a step portion of the main shaft, and the fastener is fastened to apply a fastening force to an entire shaft sleeve.   
     
     
         2 . The impeller according to  claim 1 , wherein the impeller comprises a main plate having a machined surface that is connected to the fastening hole and forms a front surface of the impeller. 
     
     
         3 . The impeller according to  claim 1 , wherein the fastening hole, the shaft insertion hole, and the sleeve insertion hole are arranged in this order, in a straight line. 
     
     
         4 . A pump comprising:
 an impeller, a fastener, and a shaft sleeve according to  claim 1 ;   a seal washer configured to close a gap between a head portion of the fastener and the fastening hole; and   a seal member attached to the seal groove and configured to close a gap between the sleeve insertion hole and the shaft sleeve.   
     
     
         5 . The pump according to  claim 4 , wherein the seal washer, the impeller, and the shaft sleeve are arranged in this order, in a straight line, and
 wherein the fastener is configured to press a metal portion of the seal washer, the metal impeller, and the metal shaft sleeve against a step portion of the main shaft by a fastening force of the fastener.   
     
     
         6 . The pump according to  claim 4 , wherein the shaft sleeve has a non-rotating groove that can fit a key formed on an inner surface of the shaft insertion hole. 
     
     
         7 . The impeller according to  claim 1 , wherein the shaft sleeve has an impeller side end portion that can be inserted into the sleeve insertion hole and an anti-impeller side end portion that can be pressed against the step portion of the main shaft and is aligned with the impeller side end portion, and
 wherein the impeller side end portion is inserted into the sleeve insertion hole, and the anti-impeller side end portion is pressed against the step portion, and the fastener is fastened to apply the fastening force to the entire shaft sleeve.