Hydraulic pump

Abstract

A hydraulic pump with a drive motor, a wet chamber, at least one printed circuit board which carries electronic or electrical components for controlling the drive motor and is located in the wet chamber, and an evaluation unit and at least two electrodes which are located on the printed circuit board in the wet chamber. The evaluation unit can detect a change in the capacitance of a capacitor formed by the two electrodes.

1 . Hydraulic pump with a drive motor, a wet chamber, at least one printed circuit board which carries electronic or electrical components for controlling the drive motor and is located in the wet chamber, an evaluation unit and at least two electrodes which are located on the printed circuit board in the wet chamber, wherein the evaluation unit can detect a change in the capacitance of a capacitor formed by the two electrodes. 
     
     
         2 . Hydraulic pump according to  claim 1 , wherein the electrodes are formed by conductor tracks on the printed circuit board. 
     
     
         3 . Hydraulic pump according to  claim 1 , wherein the electrodes are formed by metallized surfaces on the surface of the printed circuit board. 
     
     
         4 . Hydraulic pump according to  claim 1 , wherein the electrodes are formed by capacitor plates that are separate from the printed circuit board and mounted on it. 
     
     
         5 . Hydraulic pump according to  claim 1 , wherein the electrodes are arranged in such a way that they are located in the upper half of the wet chamber when the hydraulic pump is in the installation position. 
     
     
         6 . Hydraulic pump according to  claim 1 , wherein the evaluation unit has a signal input with which it can receive a signal that is indicative of the current consumption of the drive motor. 
     
     
         7 . Hydraulic pump according to  claim 2 , wherein the electrodes are arranged in such a way that they are located in the upper half of the wet chamber when the hydraulic pump is in the installation position. 
     
     
         8 . Hydraulic pump according to  claim 2 , wherein the evaluation unit has a signal input with which it can receive a signal that is indicative of the current consumption of the drive motor. 
     
     
         9 . Hydraulic pump according to  claim 3 , wherein the electrodes are arranged in such a way that they are located in the upper half of the wet chamber when the hydraulic pump is in the installation position. 
     
     
         10 . Hydraulic pump according to  claim 3 , wherein the evaluation unit has a signal input with which it can receive a signal that is indicative of the current consumption of the drive motor. 
     
     
         11 . Hydraulic pump according to  claim 4 , wherein the electrodes are arranged in such a way that they are located in the upper half of the wet chamber when the hydraulic pump is in the installation position. 
     
     
         12 . Hydraulic pump according to  claim 4 , wherein the evaluation unit has a signal input with which it can receive a signal that is indicative of the current consumption of the drive motor. 
     
     
         13 . Hydraulic pump according to  claim 5 , wherein the evaluation unit has a signal input with which it can receive a signal that is indicative of the current consumption of the drive motor.