Abstract: A hydrostatic drive system of a mobile machine includes a hydraulic work system and a hydraulic work pump that is driven by an internal combustion engine and, when operated as a pump, takes in hydraulic fluid with a suction side from a tank and, with a delivery side, delivers into a delivery line that leads to the hydraulic work system. A bypass valve is provided with which, when the hydraulic work pump is operated as a motor to start the shut-off internal combustion engine, the volume flow delivered by the hydraulic work pump operated as a motor to the delivery side is diverted to the tank. The bypass valve, in the motor operation to start the shut-off internal combustion engine, is actuated into an open position that connects the delivery side of the hydraulic work pump with the tank.

Abstract: A hydrostatic drive system of a mobile machine includes a hydraulic work system and a hydraulic work pump that is driven by an internal combustion engine and, when operated as a pump, takes in hydraulic fluid with a suction side from a tank and, with a delivery side, delivers into a delivery line that leads to the hydraulic work system. A bypass valve is provided with which, when the hydraulic work pump is operated as a motor to start the shut-off internal combustion engine, the volume flow delivered by the hydraulic work pump operated as a motor to the delivery side is diverted to the tank. The bypass valve, in the motor operation to start the shut-off internal combustion engine, is actuated into an open position that connects the delivery side of the hydraulic work pump with the tank.

Abstract: A working machine, such as an industrial truck, having a spring-loaded brake having a braking position and a release position and controlled by a brake valve producing a brake-release pressure. The brake valve is operatively connected to a service brake input device, such as a brake pedal, and can be acted upon in the direction of a reduction in the brake-release pressure arising at the spring-loaded brake when the service brake input device is actuated. It being possible, on actuation, for the service brake input device to be operatively connected to a pre-stressed spring device, which is operatively connected to the brake valve and can be acted upon in the direction of an increase in the spring force on increasing actuation of the service brake input device.

Abstract: A hydrostatic drive system has a pump (1) and at least one consumer (5) controlled by a control valve (4) that can be actuated by control signals. A precharge device (10) that generates a precharge pressure is located in a reservoir line (7) that leads from the control valve (4) to a reservoir (2). The precharge device can be pressurized as a function of the control signals of the control valve (4). To make possible a recharge during the deceleration of a consumer, the precharge device (10) can be pressurized in the direction of an elevation of the precharge pressure when there is a decreasing control signal of the control valve (4).

Abstract: A hydrostatic drive system has a consumer (7), in particular a hydraulic motor, located in the open circuit. Associated with the consumer (7) is at least one pressure limiting device (11a; 11b) that can be actuated in the braking phase for the generation of a braking pressure that is present on the discharge side of the consumer (7) from a minimum response pressure in the direction of an increase of the response pressure. A feeder device (12a; 12b) provides a feed of pressure fluid into the admission side of the consumer (7). The pressure limiting device (11a; 11b) and the feeder device (12a; 12b) are integrated into a valve unit (10a; 10b).