Cooling for an electrically operated displacement pump

Abstract

An electrically operated displacement pump includes an electric motor having a stator and a rotor. The rotor is connected to the fluid displacer to power pumping by the fluid displacer. A cooling circuit extends at least partially about an exterior of a motor housing that houses the electric motor. A fan assembly blows cooling air through the cooling circuit.

1 . A displacement pump for pumping a fluid, the displacement pump comprising:
 an electric motor including a stator and a rotor;   a fluid displacer configured to pump fluid and connected to the rotor to be driven by the rotor;   a cooling circuit including a flowpath about an exterior of a motor housing that houses the electric motor, the flowpath wrapping at least 90-degrees about the motor housing; and   a fan assembly configured to blow air through the cooling circuit.   
     
     
         2 . The displacement pump of  claim 1 , further comprising:
 a control housing extending from the motor housing, wherein electrical control components of the displacement pump are disposed in the control housing; and   wherein at least a portion of the flowpath is disposed between the motor housing and the control housing such that the air blown by the fan assembly flows over and contacts both the control housing and the motor housing.   
     
     
         3 . The displacement pump of  claim 2 , wherein the portion of the flowpath is defined by a thermally conductive wall of the control housing and a thermally conductive body of the motor housing. 
     
     
         4 . The displacement pump of  claim 3 , wherein the thermally conductive body curves away from the thermally conductive wall. 
     
     
         5 . The displacement pump of  claim 3 , wherein the electrical control elements are mounted on a first side of the thermally conductive wall and a second side of the thermally conductive wall is exposed to the flowpath, the first side opposite the second side. 
     
     
         6 . The displacement pump of  claim 2 , wherein at least a portion of the fan assembly is disposed directly between the motor housing and the control housing. 
     
     
         7 . The displacement pump of  claim 1 , wherein the flowpath wraps at least 120-degrees about the motor housing. 
     
     
         8 . The displacement pump of  claim 7 , wherein the flowpath wraps at least 180-degrees about the motor housing. 
     
     
         9 . The displacement pump of  claim 1 , wherein the fan assembly includes an impeller configured to generate a radial output flow relative to a fan axis on which the impeller rotates. 
     
     
         10 . The displacement pump of  claim 9 , wherein the impeller is configured to draw air into the fan assembly from multiple inlet locations disposed about around the motor housing. 
     
     
         11 . The displacement pump of  claim 1 , wherein the flowpath is curved such that an inlet of the flowpath and an outlet of the flowpath are disposed on a same side of the motor relative to a radial line through an axis of rotation of the rotor. 
     
     
         12 . The displacement pump of  claim 11 , wherein a control housing that extends from the motor housing and within which electrical control components of the displacement pump are disposed is disposed on an opposite side of the radial line from the inlet and the outlet. 
     
     
         13 . The displacement pump of  claim 1 , wherein a main flow vector of cooling air exiting the fan assembly is perpendicular to a fan axis on which an impeller of the fan rotates and is directed directly between the motor and electrical control elements of the displacement pump. 
     
     
         14 . The displacement pump of  claim 1 , wherein a housing cover is mounted to a pump body of the displacement pump, the pump body including the motor housing, and wherein the housing cover at least partially encloses the flowpath. 
     
     
         15 . The displacement pump of  claim 14 , wherein the housing cover includes an exhaust cover extending over a portion of the motor housing downstream of the fan assembly. 
     
     
         16 . The displacement pump of  claim 15 , wherein the exhaust cover extends to a top dead center location of the motor housing. 
     
     
         17 . The displacement pump of  claim 15 , wherein the housing cover includes a baffle having a curved surface exposed to the flowpath, wherein the curved surface is configured to redirect cooling flow through the flowpath from an intermediate passage of the cooling circuit to an exhaust passage of the cooling circuit, wherein the intermediate passage is disposed between the motor housing and a housing block within which control elements of the displacement pump are disposed; and wherein the exhaust passage is disposed between the motor housing and the exhaust cover. 
     
     
         18 . The displacement pump of  claim 1 , further comprising:
 a control housing extending radially from the motor housing relative to the axis, wherein electrical control components of the displacement pump are disposed in the control housing;   wherein a portion of the flowpath is disposed between the motor housing and the control housing such that the air blown by the fan assembly flows over and contacts both the control housing and the motor housing;   wherein the portion of the flowpath is defined by a thermally conductive wall of the control housing and a thermally conductive body of the motor housing; and   wherein the electrical control components are mounted to the thermally conductive wall on an opposite side of the thermally conductive wall from the portion of the flowpath.   
     
     
         19 . The displacement pump of  claim 18 , wherein the portion of the flowpath is formed as a plurality of channels at least partially defined by the motor housing and the control housing. 
     
     
         20 . The displacement pump of  claim 18 , wherein an outlet of the fan assembly is disposed directly between the motor housing and the control housing.