Underwater motor pump

Abstract

An underwater motor pump includes a motor case that accommodates an electric motor which supplies a rotational force to an output shaft, a pump case that has a discharge pipe and that accommodates a first impeller provided on the output shaft, and an inverter case that accommodates an inverter device which controls the electric motor. The inverter case is disposed between the pump case and the motor case.

What is claimed is: 
     
         1 . An underwater motor pump comprising:
 a motor case configured to accommodate an electric motor that supplies a rotational force to an output shaft;   a pump case including a discharge pipe and configured to accommodate a first impeller provided on the output shaft; and   an inverter case configured to accommodate an inverter device that controls the electric motor,   wherein the inverter case is disposed between the pump case and the motor case.   
     
     
         2 . The underwater motor pump according to  claim 1 ,
 wherein the inverter device is disposed in contact with a lower partition wall of the inverter case.   
     
     
         3 . The underwater motor pump according to  claim 1 ,
 wherein the inverter device is disposed apart from an upper partition wall and a lower partition wall of the inverter case.   
     
     
         4 . The underwater motor pump according to  claim 1 , further comprising:
 a mechanical seal case configured to accommodate a mechanical sealing portion that rotatably seals the output shaft and a lubricating liquid that lubricates the mechanical sealing portion,   wherein the inverter case is disposed between the mechanical seal case and the motor case.   
     
     
         5 . The underwater motor pump according to  claim 1 , further comprising:
 a mechanical seal case configured to accommodate a mechanical sealing portion that rotatably seals the output shaft and a lubricating liquid that lubricates the mechanical sealing portion,   wherein the inverter case is disposed between the mechanical seal case and the pump case.   
     
     
         6 . The underwater motor pump according to  claim 4 ,
 wherein the output shaft includes a second impeller that is disposed inside the mechanical seal case and that causes the lubricating liquid to flow toward the inverter case.   
     
     
         7 . The underwater motor pump according to  claim 1 ,
 wherein the inverter case accommodates a mechanical sealing portion that rotatably seals the output shaft and a lubricating liquid that lubricates the mechanical sealing portion, and   the inverter device is disposed inside the inverter case.   
     
     
         8 . The underwater motor pump according to  claim 7 ,
 wherein the output shaft includes a second impeller that is disposed inside the inverter case and that causes the lubricating liquid to flow toward the inverter case.   
     
     
         9 . The underwater motor pump according to  claim 2 , further comprising:
 a mechanical seal case configured to accommodate a mechanical sealing portion that rotatably seals the output shaft and a lubricating liquid that lubricates the mechanical sealing portion,   wherein the inverter case is disposed between the mechanical seal case and the motor case.   
     
     
         10 . The underwater motor pump according to  claim 3 , further comprising:
 a mechanical seal case configured to accommodate a mechanical sealing portion that rotatably seals the output shaft and a lubricating liquid that lubricates the mechanical sealing portion,   wherein the inverter case is disposed between the mechanical seal case and the motor case.   
     
     
         11 . The underwater motor pump according to  claim 2 , further comprising:
 a mechanical seal case configured to accommodate a mechanical sealing portion that rotatably seals the output shaft and a lubricating liquid that lubricates the mechanical sealing portion,   wherein the inverter case is disposed between the mechanical seal case and the pump case.   
     
     
         12 . The underwater motor pump according to  claim 3 , further comprising:
 a mechanical seal case configured to accommodate a mechanical sealing portion that rotatably seals the output shaft and a lubricating liquid that lubricates the mechanical sealing portion,   wherein the inverter case is disposed between the mechanical seal case and the pump case.   
     
     
         13 . The underwater motor pump according to  claim 9 ,
 wherein the output shaft includes a second impeller that is disposed inside the mechanical seal case and that causes the lubricating liquid to flow toward the inverter case.   
     
     
         14 . The underwater motor pump according to  claim 10 ,
 wherein the output shaft includes a second impeller that is disposed inside the mechanical seal case and that causes the lubricating liquid to flow toward the inverter case.   
     
     
         15 . The underwater motor pump according to  claim 11 ,
 wherein the output shaft includes a second impeller that is disposed inside the mechanical seal case and that causes the lubricating liquid to flow toward the inverter case.   
     
     
         16 . The underwater motor pump according to  claim 12 ,
 wherein the output shaft includes a second impeller that is disposed inside the mechanical seal case and that causes the lubricating liquid to flow toward the inverter case.   
     
     
         17 . The underwater motor pump according to  claim 2 ,
 wherein the inverter case accommodates a mechanical sealing portion that rotatably seals the output shaft and a lubricating liquid that lubricates the mechanical sealing portion, and   the inverter device is disposed inside the inverter case.   
     
     
         18 . The underwater motor pump according to  claim 3 ,
 wherein the inverter case accommodates a mechanical sealing portion that rotatably seals the output shaft and a lubricating liquid that lubricates the mechanical sealing portion, and   the inverter device is disposed inside the inverter case.   
     
     
         19 . The underwater motor pump according to  claim 17 ,
 wherein the output shaft includes a second impeller that is disposed inside the inverter case and that causes the lubricating liquid to flow toward the inverter case.   
     
     
         20 . The underwater motor pump according to  claim 18 ,
 wherein the output shaft includes a second impeller that is disposed inside the inverter case and that causes the lubricating liquid to flow toward the inverter case.