Motor pump bearing

Abstract

A bearing that is used in a motor pump in which a liquid is, not only pumped by means of an impeller driven by the pump, but also is used to lubricate components of the motor pump including the motor pump shaft. The bearing is for supporting the shaft at at least one location of the shaft. The bearing is constructed of a bronze material having added thereto a small amount of graphite, preferably around 2.5%.

1 . A bearing that is used in a motor pump in which water is not only pumped by means of an impeller driven by the pump, but also is used to lubricate components of the motor pump including the motor pump shaft which is a ceramic shaft, the bearing for supporting the shaft at at least one location of the shaft, and the bearing constructed of a bronze material having added thereto a small amount of graphite. 
     
     
         2 . The bearing of  claim 1  wherein the small amount of graphite is in a range of 1% to 10% of the total material comprising the bearing. 
     
     
         3 . The bearing of  claim 2  wherein the small amount of graphite is in a range of 2.5% to 5% of the total material comprising the bearing. 
     
     
         4 . The bearing of  claim 1  wherein the bearing is constructed using a sintering technique that defines a porosity of the bearing. 
     
     
         5 . The bearing of  claim 4  wherein the graphite is mixed as a powder with a bronze powder prior to sintering. 
     
     
         6 . The bearing of  claim 4  wherein the graphite is impregnated into the bronze after sintering. 
     
     
         7 . The bearing of  claim 1  wherein the motor pump is a canned motor pump. 
     
     
         8 . The bearing of  claim 1  wherein the bearing is non-oil impregnated. 
     
     
         9 . A method of forming a sleeve type bearing for use in a motor pump in which water is not only pumped by means of an impeller driven by the pump, but also is used to lubricate components of the motor pump including the motor pump shaft which is a ceramic shaft, the method comprising the steps of:
 providing a main bearing component as a bronze powder;   providing a small amount of an additive as a graphite powder;   wherein the small amount of the additive is less than 10% of the total material of the combined powders;   mixing the bronze and graphite powders together to form a composite material; and   heating the mixed composite material to form the sleeve type bearing.   
     
     
         10 . The method of  claim 9  wherein the heating step includes sintering the powder mixture. 
     
     
         11 . The method of  claim 9  wherein the small amount of graphite is in a range of 1% to 10% of the total material comprising the bearing. 
     
     
         12 . The method of  claim 10  wherein the small amount of graphite is in a range of 2.5% to 5% of the total material comprising the bearing. 
     
     
         13 . The method of  claim 9  wherein the bearing is non-oil impregnated. 
     
     
         14 . A method of forming a sleeve type bearing for use in a motor pump in which water is not only pumped by means of an impeller driven by the pump, but also is used to lubricate components of the motor pump including the motor pump shaft which is a ceramic shaft, the method comprising the steps of:
 providing a main bearing component as a bronze powder;   providing a small amount of an additive as a graphite powder;   wherein the small amount of the additive is less than 10% of the total material of the combined powders;   heating the bronze powder to form the sleeve type bearing; and   adding the small amount of graphite to the formed sleeve type bearing.   
     
     
         15 . The method of  claim 14  wherein the heating step includes sintering the bronze powder. 
     
     
         16 . The method of  claim 14  wherein the graphite is added after sintering by impregnating the graphite into the bronze bearing. 
     
     
         17 . The method of  claim 14  wherein the small amount of graphite is in a range of 1% to 10% of the total material comprising the bearing. 
     
     
         18 . The method of  claim 17  wherein the small amount of graphite is in a range of 2.5% to 5% of the total material comprising the bearing. 
     
     
         19 . The method of  claim 14  wherein the bearing is non-oil impregnated. 
     
     
         20 . A motor pump comprising:
 a pump housing;   a motor housing;   a pump shaft supported in the motor housing and including an impeller extending into the pump housing;   a rotor-stator structure in the motor housing for driving the shaft;   a front bearing and a rear bearing for supporting the shaft;   an annular bearing support member to which the front bearing is mounted;   wherein each bearing is constructed of a bronze material, and each bearing has added thereto a small amount of graphite;   and wherein each bearing is non-oil impregnated.   
     
     
         21 . The motor pump of  claim 20  wherein the motor is a canned motor pump in which the fluid that is being pumped is water and passes through the motor housing. 
     
     
         22 . The motor pump of  claim 20  wherein the small amount of graphite is in a range of 1% to 10% of the total material comprising the bearing. 
     
     
         23 . The motor pump of  claim 20  wherein the small amount of graphite is in a range of 2.5% to 5% of the total material comprising the bearing. 
     
     
         24 . The motor pump of  claim 20  wherein the bearing is constructed using a sintering technique that defines a porosity of the bearing. 
     
     
         25 . The motor pump of  claim 24  wherein the graphite is mixed as a powder with a bronze powder prior to sintering. 
     
     
         26 . The motor pump of  claim 20  wherein the graphite is impregnated into the bronze after sintering.