Hydraulic drive

Abstract

A hydraulic drive for a hydraulic load or for a hydraulic system includes a variable-displacement pump which is mechanically coupled to a variable-speed drive motor. The hydraulic drive also includes a control configured to adjust at least the capacity of the pump and optionally the speed of the drive motor. The hydraulic drive also includes a torque detecting device configured to detect or calculate a current output torque of the drive motor. Based on the current output torque of the drive motor, the capacity of the pump is set to a value at which the current output torque is at or below a set maximum value.

1 . A hydraulic drive for a hydraulic consumer or a hydraulic system comprising:
 a variable displacement pump mechanically coupled to a variable speed drive motor; and   a control configured to adjust a stroke volume of the variable displacement pump,   wherein the variable displacement pump is configured to be torque-controlled.   
     
     
         2 . The hydraulic drive as claimed in  claim 1 , further comprising:
 a pressure sensing device configured to sense a prevailing pressure at the hydraulic consumer or in the hydraulic system,   wherein the variable displacement pump is configured to be adjusted such that a predetermined value of an output torque of the drive motor is equivalent to a constant value which is equivalent to the consumer/hydraulic system pressure multiplied by the stroke volume of the variable displacement pump.   
     
     
         3 . The hydraulic drive as claimed in  claim 2 , wherein the variable displacement pump is equipped with a mechanical-hydraulic torque regulator. 
     
     
         4 . The hydraulic drive as claimed in  claim 1 , wherein the drive motor is configured such that a rotation speed thereof is adjusted based upon a prevailing stroke volume of the variable displacement pump such that a predetermined movement rate of the hydraulic consumer is maintained.