Pump assembly

Abstract

A pump assembly includes an electrical drive motor, at least one impeller ( 14 ) which is rotatingly driven by the electrical drive motor as well as a control device ( 17 ) which activates the drive motor. The control device ( 17 ) is configured such that the control device ( 17 ) selectively activates the drive motor in at least one first or a second operating mode. In a first operating mode, the drive motor is activated by the control device ( 17 ) such that a rotor ( 6 ) of the drive motor continuously rotates. In the second operating mode the drive motor is controlled by the control device ( 17 ) such that the rotor ( 6 ) of the drive motor is moved further stepwise manner in at least one selected angular step of preferably smaller than 360°.

1 . A pump assembly comprising:
 an electrical drive motor;   at least one impeller which is rotatingly driven by the electrical drive motor; and   a control device which activates the drive motor, wherein the control device is configured to selectively activate the drive motor in at least one first operating mode or in a second operating mode, wherein in the first operating mode, the drive motor is activated by the control device such that a rotor of the drive motor continuously rotates for producing a flow and a pressure at the impeller, and in the second operating mode, the drive motor is controlled by the control device such that the rotor of the drive motor is moved further stepwise in at least one selected angular step for reaching a certain angular position.   
     
     
         2 . A pump assembly according to  claim 1 , wherein the control device is configured such that the drive motor rotates at higher angular speed in the first operating mode than in the second operating mode. 
     
     
         3 . A pump assembly according to  claim 1 , wherein the control device is configured such that in the first operating mode, the drive motor in is speed adjustable and closed-loop controllable. 
     
     
         4 . A pump assembly according to  claim 1 , wherein the control device is configured such that in the second operating mode, the drive motor is controlled by the control device with an open-loop. 
     
     
         5 . A pump assembly according to  claim 1 , wherein the control device is configured such that in the second operating mode, the drive motor is activated by the control device at a frequency <10 Hertz and/or the motor current corresponds to twice to fourfold the rated amperage, for which the drive motor is designed. 
     
     
         6 . A pump assembly according to  claim 1 , wherein the control device comprises a frequency converter. 
     
     
         7 . A pump assembly according to  claim 1 , wherein the control device is configured such that a number and/or a size of the individual angular steps, in which the rotor is moved in the second operating mode, is selectable. 
     
     
         8 . A pump assembly according to  claim 1 , wherein the control device is configured such that the control device activates the drive motor such that a drive motor rotation direction in the second operating mode is opposite to a drive motor rotation direction in the first operating mode. 
     
     
         9 . A pump assembly according to  claim 1 , wherein the rotor of the drive motor, in addition to being coupled to the at least one impeller, is coupled to at least one further movable component via a releasable coupling. 
     
     
         10 . A pump assembly according to  claim 9 , wherein the releasable coupling is rotation-direction dependently releasable such that in a first rotation direction the releasable coupling is engaged and in the opposite second rotation direction the releasable coupling is released. 
     
     
         11 . A pump assembly according to  claim 9 , wherein the releasable coupling is formed at a face end of a rotor shaft of the rotor and has a saw-tooth profile. 
     
     
         12 . A pump assembly according to  claim 9 , wherein the at least one further movable component is a valve element part of a mixing valve and/or switch-over valve. 
     
     
         13 . A pump assembly according to  claim 12 , wherein:
 the valve element is configured and arranged such that the valve element is rotatingly movable between at least two switching positions; and   a rotation axis of the valve element is arranged aligned to a rotation of the drive motor.   
     
     
         14 . A pump assembly according to  claim 12 , wherein the valve element is arranged in the pump assembly such that the valve element comprises a pressure surface, upon which a pressure prevailing at the outlet side of the at least one impeller acts, and the valve element is movably mounted in a direction transverse to the pressure surface between a bearing position, in which the valve element bears on at least one contact surface, and a released position, in which the valve element is released or distanced to the contact surface, wherein a restoring element is provided, said restoring element producing a restoring force which is directed oppositely to the pressing force which is produced by the pressure on the pressure surface. 
     
     
         15 . A pump assembly according to  claim 14 , wherein the contact surface is a sealing surface. 
     
     
         16 . A pump assembly according to  claim 14 , wherein a movement path between the bearing position and a released position is different to a movement path between the at least two switching positions of the valve element. 
     
     
         17 . A pump assembly according to  claim 1 , wherein the pump assembly is configured as a circulation pump assembly.