Abstract: A variable displacement hydrostatic power unit (7) is connected with an internal combustion engine (2). The power unit (7) operates as a pump to deliver hydraulic fluid to at least one consumer (V) and operates as a motor as a hydraulic starter for the internal combustion engine (2). Hydraulic fluid from a hydraulic accumulator (25) is supplied to the power unit (7) operated as a motor. The power unit (7) includes a spring device (55) which, when the internal combustion engine (2) is shut off, actuates a displacement volume control device (50) into a position with the maximum displacement volume. When the power unit (7) is actuated with hydraulic fluid from the hydraulic accumulator (25), the internal combustion engine (7) is immediately started by the power unit (7) without the need for an immediately preceding adjustment of the displacement volume control device (50) of the power unit (7).

Abstract: A drive system (1) for a harvesting machine has a drive train (4) connected by a coupling device (5) with a drive motor (6). The drive train (4) has a hydrostatic transmission (10) with a variable displacement pump (11) and a hydraulic motor (12) connected in a closed circuit to the pump (11). The hydraulic motor (12) is connected to a feeder device (2). For quickly stopping the feeder device (2), the pump (11) is set to a displacement of zero by an electronic control system (15) and the feeder device (2) is braked by a pressure protection device (40). For a chopper device (3), the hydraulic motor (12) is cut off by the electronic control system (15). The drive train (4) is isolated from the drive motor (6) by uncoupling the coupling device (5) and the pump (11) is set to the maximum displacement volume.

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 power split transmission (LG) of vehicle a traction drive (F) includes a continuously variable transmission (G) and a summing transmission (SG). The continuously variable transmission (G) has a primary unit (P) and a secondary unit (S) driven by the primary unit (P). The primary unit (P) has a driveshaft (TW1) connected, directly and without the interposition of a clutch device, with the sun gear (SR) of the summing transmission (SG). The secondary unit (S) has a driveshaft (TW2) connected, without the interposition of a clutch device, with a ring gear (HR) or a planetary carrier (PT) of the summing transmission (SG). The planetary carrier (PT) or the ring gear (HR) of the summing transmission (SG) form an output element of the summing transmission (SG), which is in a driving connection with the wheel drive.

Abstract: A hydrostatic positive displacement machine (2) is operated in a closed circuit and delivers hydraulic fluid into a working circuit. The displacement volume is varied by a control device (6) having a variable displacement piston device (7). The machine (2) has a swivel-back device (40) which, in the event of a decrease of the feed pressure from the feed pressure source (11), guarantees actuation of the machine (2) toward a reduction of the displacement volume. The swivel-back device (40) includes at least one pressure sequence valve (41), which is in communication on the input side with the working circuit of the machine (2). In the event of a decrease in the feed pressure from the feed pressure source (11) below a limit pressure, the pressure sequence valve (41) makes it possible to supply the control device (6) of the machine (2) with hydraulic fluid from the working circuit.

Abstract: A hydrostatic starter device (10) for an internal combustion engine (2) having a hydrostatic power unit (11) connected with the output shaft (4) of the internal combustion engine (2) is driven with hydraulic fluid from a hydraulic fluid accumulator (12). The hydrostatic starter device (10) has an electrohydraulic charging device (30) to charge the hydraulic fluid accumulator (12) with hydraulic fluid and the hydrostatic power unit (11) is in a drive connection by a clutch device (25) with the internal combustion engine (2). The hydrostatic power unit (11) can be connected in a drive connection with the internal combustion engine (2) by the clutch device (25).

Abstract: A drive train of a vehicle has a drive motor and a traction drive driven by the drive motor. A hydraulic work system has at least one hydraulic pump driven by the drive motor. To deliver torque into the drive train and/or to absorb torque from the drive train, the drive train is provided with an additional hydraulic machine which can be placed in communication with a hydraulic pressure accumulator and/or a tank and can be operated as a pump and a motor in the same direction of rotation. The hydraulic machine has an inlet connection and an outlet connection and a switching valve device is provided to control the connection of the inlet connection and the outlet connection with the pressure accumulator or the tank.

Abstract: A hydrostatic axial piston machine (1), in particular an axial piston motor, has a rotating cylinder block (3) with a cylinder block body (3a) and a cylinder block neck (3b), and a drive shaft (14). Located in the cylinder block body (3a) are a plurality of piston bores (4) with pistons (5) that can move longitudinally and which are supported on a swashplate (7). Between the cylinder block neck (3b) which projects from the cylinder block body (3a) and extends in the direction of the swashplate (7) and the drive shaft (14) there is a synchronization gearing (20) and a braking device (25) that acts on the cylinder block (3). In the vicinity of the cylinder block neck (3b) within the axial dimension of the cylinder block body (3a), there is an additional synchronization gearing (21). The additional synchronization gearing (21) has a larger gear tooth clearance (SF) in the vicinity of the cylinder block body (3a) than the synchronization gearing (21) in the vicinity of the cylinder block neck (3b).

Abstract: A hydromechanical transmission has a hydraulic pump-driven hydraulic motor of a hydrostatic continuously variable transmission and a mechanical multi-step variable speed transmission connected to a drive shaft of the hydraulic motor, which can be shifted into operation by a gear shifting device. In order to adapt the hydromechanical transmission with as compact as possible a design to diverse installation cases with little effort, the gear shifting device is arranged directly adjacent to the hydraulic motor and is consolidated with the latter into a preassembled constructional unit.

Abstract: A hydrostatic power-unit (7) is connected with an internal combustion engine (2). The suction side (S) of the power-unit (7), when operating as a pump, sucks hydraulic fluid from a tank (9) and delivers into a delivery side (P), and when operating as a motor is driven by hydraulic fluid from a hydraulic accumulator (20). A check valve device (30) is located in the suction side (S) to provide a pressure increase when the power-unit (7) is operated as a motor. The check valve device (30) has a check valve (32) operated by an actuator device (31). The actuator device (31) actuates the check valve (32) between a closed position (32a) in which a connection of the suction side (S) with the tank (9) is shut off, and an open position (32b) in which the connection of the suction side (S) to the tank (9) is opened.

Abstract: A hydrostatic variable displacement pump (2) has a displacement volume set by an electro-hydraulic control device (10) provided with a safety function. In a fault scenario, the variable displacement pump (2) is set to a neutral position. The electro-hydraulic control device (10) has a single electro-hydraulic setpoint encoder (30) to specify the setpoint of the displacement volume of the variable displacement pump (2) and an electrically actuatable valve device (35) connected in series downstream of the setpoint encoder (30), by which the direction of displacement of the variable displacement pump (2) is controlled and which is provided with the safety function.

Abstract: A power split transmission (LG) of vehicle a traction drive (F) includes a continuously variable transmission (G) and a summing transmission (SG). The continuously variable transmission (G) has a primary unit (P) and a secondary unit (S) driven by the primary unit (P). The primary unit (P) has a driveshaft (TW1) connected, directly and without the interposition of a clutch device, with the sun gear (SR) of the summing transmission (SG). The secondary unit (S) has a driveshaft (TW2) connected, without the interposition of a clutch device, with a ring gear (HR) or a planetary carrier (PT) of the summing transmission (SG). The planetary carrier (PT) or the ring gear (HR) of the summing transmission (SG) form an output element of the summing transmission (SG), which is in a driving connection with the wheel drive.

Abstract: A variable displacement hydrostatic power unit (7) is connected with an internal combustion engine (2). The power unit (7) operates as a pump to deliver hydraulic fluid to at least one consumer (V) and operates as a motor as a hydraulic starter for the internal combustion engine (2). Hydraulic fluid from a hydraulic accumulator (25) is supplied to the power unit (7) operated as a motor. The power unit (7) includes a spring device (55) which, when the internal combustion engine (2) is shut off, actuates a displacement volume control device (50) into a position with the maximum displacement volume. When the power unit (7) is actuated with hydraulic fluid from the hydraulic accumulator (25), the internal combustion engine (7) is immediately started by the power unit (7) without the need for an immediately preceding adjustment of the displacement volume control device (50) of the power unit (7).

Abstract: A variable displacement hydrostatic power unit (7) is in a drive connection with an internal combustion engine (2). When operated as a pump, the power unit (7) delivers hydraulic fluid to at least one consumer (V). When operated as a motor, the power unit (7) is a hydraulic starter for the internal combustion engine (2) and is supplied with hydraulic fluid from a hydraulic accumulator (25). The displacement volume of the power unit (7) is set by a displacement volume control device (50) actuated by a positioning device (52). The displacement volume control device (50) is displaced into a position with maximum displacement volume by a corresponding actuation of the positioning device (52) chronologically prior to the shutoff of the internal combustion engine (2). A securing device (60) holds the displacement volume control device (50) in the maximum displacement volume position when the internal combustion engine (2) is shut off.

Abstract: A drive train (1) includes an internal combustion engine (2) and working hydraulics (4) having at least one hydraulic pump (7). When operated as a pump, the hydraulic pump (7) sucks hydraulic fluid from a tank (9) and delivers into a delivery line (10) that leads to the working hydraulics (4). When operated as a motor, the hydraulic pump (7) is supplied with hydraulic fluid from a hydraulic accumulator (25). The drive train (1) has a charge pump (20) to supply a charging circuit (23). The charge pump (20), when operated as a pump, sucks hydraulic fluid out of the tank (9) and delivers into a charge pressure line (22) that leads to a charging circuit (23), and the charge pump (20) when operated as a motor is supplied with hydraulic fluid from the hydraulic accumulator (25).

Abstract: A drive train (1) has an internal combustion engine (2), a traction drive (3), and working hydraulics (4) having at least one hydraulic pump (7). A connecting line (26) leads to a hydraulic accumulator (25) and is connected to a delivery line (10) of the hydraulic pump (7) that leads to the working hydraulics (4). A shutoff valve (30) is located in the connecting line (26). The shutoff valve (30) is a check valve (31) that opens automatically and as a function of the pressure to allow a flow to the hydraulic accumulator (25). A pressure relief valve (32) is operatively associated with the connecting line (26) between the shutoff valve (30) and the hydraulic accumulator (25).

Abstract: A hydrostatic starter device (10) for an internal combustion engine (2) having a hydrostatic power unit (11) connected with the output shaft (4) of the internal combustion engine (2) is driven with hydraulic fluid from a hydraulic fluid accumulator (12). The hydrostatic starter device (10) has an electrohydraulic charging device (30) to charge the hydraulic fluid accumulator (12) with hydraulic fluid and the hydrostatic power unit (11) is in a drive connection by a clutch device (25) with the internal combustion engine (2). The hydrostatic power unit (11) can be connected in a drive connection with the internal combustion engine (2) by the clutch device (25).

Abstract: A hydrostatic positive displacement machine (1) with a variable displacement volume includes a cradle (3) pivoted by a hydraulic positioning device (7) having a positioning piston device (8). A position-controlled control valve (10) generates a control pressure and includes axially displaceable and locked setting valve means (20) and the rotatable feedback valve means (21). Control cross sections are exposed by an axial displacement of the setting valve means (20) relative to the feedback valve means (21) and are closed by rotational movement of the feedback valve means (21) relative to the setting valve means (20).

Abstract: A drive system (1) for a harvesting machine has a drive train (4) connected by a coupling device (5) with a drive motor (6). The drive train (4) has a hydrostatic transmission (10) with a variable displacement pump (11) and a hydraulic motor (12) connected in a closed circuit to the pump (11). The hydraulic motor (12) is connected to a feeder device (2). For quickly stopping the feeder device (2), the pump (11) is set to a displacement of zero by an electronic control system (15) and the feeder device (2) is braked by a pressure protection device (40). For a chopper device (3), the hydraulic motor (12) is cut off by the electronic control system (15). The drive train (4) is isolated from the drive motor (6) by uncoupling the coupling device (5) and the pump (11) is set to the maximum displacement volume.

Abstract: A hydrostatic positive displacement machine (2) is operated in a closed circuit and delivers hydraulic fluid into a working circuit. The displacement volume is varied by a control device (6) having a variable displacement piston device (7). The machine (2) has a swivel-back device (40) which, in the event of a decrease of the feed pressure from the feed pressure source (11), guarantees actuation of the machine (2) toward a reduction of the displacement volume. The swivel-back device (40) includes at least one pressure sequence valve (41), which is in communication on the input side with the working circuit of the machine (2). In the event of a decrease in the feed pressure from the feed pressure source (11) below a limit pressure, the pressure sequence valve (41) makes it possible to supply the control device (6) of the machine (2) with hydraulic fluid from the working circuit.