Variable output centrifugal pump

Abstract

A variable output pump assembly includes an input drive member and a primary pump member operatively driven thereby. A second drive member supplements the pump assembly. A magnetic coupling is interposed between the input drive member and the second drive member to variably drive the pump assembly.

1 . A variable output pump assembly comprising:
 an input drive member;   a primary pump member operatively driven by the input drive member;   a second drive member; and   a variable torque coupling interposed between the input drive member and the second drive member to vary speed output of the second drive member.   
     
     
         2 . The variable output pump assembly of  claim 1  wherein the coupling is a variable magnetic coupling interface between the input drive member and the second drive member. 
     
     
         3 . The variable output pump assembly of  claim 2  wherein the magnetic coupling interface includes a magnet and a magnet/ferro-magnetic member in spaced relation and the spacing therebetween is selectively altered to vary the magnetic coupling strength therebetween. 
     
     
         4 . The variable output pump assembly of  claim 3  wherein one of the magnet and magnet/ferro-magnetic member is operatively connected to an actuator that selectively moves the one of the magnet and magnet/ferro-magnetic member toward and away from the other of the magnet and magnet/ferro-magnetic member. 
     
     
         5 . The variable output pump assembly of  claim 4  wherein the input drive member is connected to the primary pump member which includes a primary impeller, and a secondary pump member operatively driven by the second drive member at a speed responsive to the coupling. 
     
     
         6 . The variable output pump assembly of  claim 5  further comprising a ring gear of a planetary gear assembly also operatively connected to the input drive member for rotation therewith. 
     
     
         7 . The variable output pump assembly of  claim 6  further comprising a planetary gear operatively driven by the ring gear such that the secondary pump member that includes a secondary impeller operatively associated with the planetary gear assembly rotates at a different rotational speed. 
     
     
         8 . The variable output pump assembly of  claim 7  wherein the carrier receives one of the magnet and the magnet/ferro-magnetic member and a fixed housing assembly receives the other of the magnet and magnet/ferro-magnetic member. 
     
     
         9 . The variable output pump assembly of  claim 8  wherein the planetary gear assembly includes at least one planetary gear that receives a rotational drive input from the ring gear, and drives a sun gear in response thereto. 
     
     
         10 . The variable output pump assembly of  claim 9  wherein the secondary impeller has an inlet receiving output flow from an outlet of the primary impeller. 
     
     
         11 . The variable output pump assembly of  claim 2  wherein the magnetic coupling interface includes a magnet and a magnet/ferro-magnetic member, where one of the magnet and magnet/ferro-magnetic material is located on a first portion of a planetary gear arrangement. 
     
     
         12 . The variable output pump assembly of  claim 11  wherein the other of the magnet and magnet/ferromagnetic material is located on a second portion of the planetary gear arrangement. 
     
     
         13 . The variable output pump assembly of  claim 11  wherein the magnet is located on the transmission housing and the magnet/ferro-magnetic material is on the first portion of the planetary gear arrangement. 
     
     
         14 . The variable output pump assembly of  claim 6  wherein magnet is located on a first carrier of the planetary gear arrangement and the magnet/ferro-magnetic material is operatively associated with a planet of a second carrier. 
     
     
         15 . The variable output pump assembly of  claim 14  wherein the planet of the second carrier is operatively associated with a pinion gear to supplement rotation of the input drive member. 
     
     
         16 . The variable output pump assembly of  claim 15  further comprising an actuator that selectively advances and retracts the magnet/ferro-magnetic material of the planet toward the magnet of the first carrier. 
     
     
         17 . A method of varying speed output in a drive transmission assembly comprising:
 providing a first drive member;   providing a second drive member;   positioning a magnetic coupling between the first drive member and the second drive member to selectively vary the speed output of the second drive member relative to the first drive member.   
     
     
         18 . The method of  claim 17  wherein the magnetic coupling positioning step placing one of a magnet and magnet/ferro-magnetic member in spaced relation. 
     
     
         19 . The method of  claim 18  wherein the spacing between the magnet and magnet/ferro-magnetic member is selectively altered to vary the magnetic coupling strength therebetween. 
     
     
         20 . The method of  claim 20  further including selectively moving one of the magnet and magnet/ferro-magnetic member toward and away from the other of the magnet and magnet/ferro-magnetic member. 
     
     
         21 . The method of  claim 17  further comprising providing a primary pump member and driving an input shaft of the primary pump member via the first drive member. 
     
     
         22 . The method of  claim 21  further comprising providing a secondary pump member and operatively driving the secondary pump member via the second drive member at a speed responsive to the magnetic coupling.