Abstract: A hydrostatic drive system includes a differential cylinder connected in a closed circuit to a high-pressure pump. A piston-side compression chamber and a piston-rod-side compression chamber of the differential cylinder are in communication with the high-pressure pump. The closed circuit includes a protection device having first and second protection valve devices that each includes a pressure relief valve and an anti-cavitation valve. The pressure relief valve of the first protection valve device is provided with an override device, by means of which the opening pressure of the pressure relief valve can be varied. When the high-pressure pump delivers into the piston-rod-side compression chamber, the pressure relief valve of the first protection valve device is adjusted by means of the override device to a reduced opening pressure and the differential volumetric flow flows out via the pressure relief valve to a low-pressure system.

Abstract: A hydrostatic traction drive includes a first hydrostatic motor and at least one drive unit effectively connected with the motor. The motor is connected with a second motor into a modular unit, and the motors are positioned coaxially with respect to each other. At least one of the motors has a variable displacement. Between the motors and/or between at least one motor and the drive unit that is effectively connected with it, there is a clutch that can be disengaged in operation. On the motor-side of the hydrostatic traction drive, it thereby becomes possible to vary the transmission ratio continuously and without interrupting the traction. The clutch connected between the motors makes it possible to disconnect one of the motors and thereby reduce power loss and wear. Output-side clutches make it possible to disengage drive units from the motors.

Abstract: A hydrostatic traction drive includes a first hydrostatic motor and at least one drive unit effectively connected with the motor. The motor is connected with a second motor into a modular unit, and the motors are positioned coaxially with respect to each other. At least one of the motors has a variable displacement. Between the motors and/or between at least one motor and the drive unit that is effectively connected with it, there is a clutch that can be disengaged in operation. On the motor-side of the hydrostatic traction drive, it thereby becomes possible to vary the transmission ratio continuously and without interrupting the traction. The clutch connected between the motors makes it possible to disconnect one of the motors and thereby reduce power loss and wear. Output-side clutches make it possible to disengage drive units from the motors.