Robert Boschgmbh

Bosch Rexroth Ag

Brueninghaus Hydromatik Gmbh

Martin Behm

Matthias Mueller

Heiko Witte

Michael Mast

Bernhard Kuemmel

Steffen Mutschler

Rolf Rathke

Christine Ehret

Matthias Müller

A hydrostatic transmission implements a braking system, in which at least one adjustable traction motor acting as a pump is supported via a closed circuit on an adjustable axial piston machine acting as a motor, which in turn is supported on an internal combustion engine. Since the internal combustion engine should not be rotated at excessive revolution rates, a control unit adjusts the swivel angle of the axial piston machine during braking. The axial piston machine is load-sensitive, as a relationship between the control pressure and the revolution rate and the pivot angle of the machine consists of a pressure difference between the two working lines of the closed circuit. Using a pre-control, a swivel angle of the axial piston machine is set during braking, and the swivel angle is corrected by a revolution rate controller, such that a target revolution rate is obtained on the combustion engine.

Hydrostatic transmission and method for braking using the same

A hydrostatic transmission for a traction drive of a mobile working machine includes a variable-displacement pump and one or more motors connected to one another in a closed hydraulic circuit. An electronic control unit of the hydrostatic transmission is configured to initiate and to end a braking operation by the hydrostatic transmission if a traveling speed of the mobile working machine reaches a threshold value. The threshold value is adjustable by the electronic control unit automatically or in a manner dependent on a driver demand. The braking torque is also adjustable.

A hydrostatic transmission for a traction drive includes a variable-displacement pump and one or more motors coupled to one another in a closed hydraulic circuit. A braking operation is introduced into the traction drive via the hydrostatic transmission, and is controlled in closed-loop fashion by an electronic control unit. A braking torque is controlled in closed-loop fashion indirectly by a swept volume of the secondary unit, for which purpose one or two closed-loop controllers are provided.

A hydrostatic transmission is configured to realize a braking operation in which at least one adjustable traction motor, which acts as a pump, is supported via a closed circuit on an adjustable axial piston pump, which acts as a motor, and which in turn is supported on an internal combustion engine. Since overspeeding of the latter should be avoided, a control unit adjusts the pivot angle of the pump in accordance with a characteristic map which represents a relationship between a setting force and a pressure difference of two working lines of a closed circuit, a pump rotational speed, and the pivot angle. Thus, characteristic-map-based pilot control of the pivot angle of the pump is possible and feedback of the present pivot angle is omitted.

A hydrostatic traction drive in a closed hydraulic circuit includes two hydraulic machines in the closed hydraulic circuit and a control unit configured to control a braking torque of the traction drive. A method for controlling the hydrostatic traction drive includes controlling the braking torque for the hydrostatic traction drive.

Hydrostatic traction drive in closed hydraulic circuit and method for controlling the hydrostatic traction drive

The invention relates to a drive () having an energy storage device and a method for storing brake energy. A drive () has an energy storage device having a hydrostatic piston engine () and a storage element () which is connected thereto. In a high-pressure storage line (), an adjustable throttle location () is arranged between the piston engine () and the storage element (). During the braking operation, the adjustable throttle location () is adjusted in accordance with a detected requested brake torque. The pressure medium is conveyed from the hydrostatic piston engine () via the adjustable throttle location () into the storage element ().

Drive having an energy storage device and method for storing kinetic energy

A method and device for controlled braking of a vehicle using a hydrostatic drive is provided. Two pivotal hydraulic motors are connected to a respective axle of the drive, driven by a hydraulic pump and regulated by a respective regulating circuit. For each axle of the drive, a respective reference variable containing the difference between a set value and the actual value of a speed of the driven wheel is continuously determined and fed back to the respective regulating circuit. A displacement of the axle load of the vehicle from a current deceleration (a) of the vehicle is dynamically determined. A resultant braking force acting on the axle driven by the hydraulic motor is determined and put into effect by the hydraulic motor through adjusting a corresponding pivot angle. A deceleration-dependent distribution of the braking force is then provided to the respective axle by a control program.

Method and device for hydrostatically braking a vehicle

The invention relates to a drive with an energy recovery and retarder function. The drive () comprises a hydrostatic piston engine () which is connected to an accumulator () for storing pressure energy and to a pressure limiting valve () for generating a braking action. Arranged downstream of the pressure limiting valve () is a cooler (). The drive () also comprises a hydraulic motor () for driving a cooler fan (), wherein the hydraulic motor () is acted on with a pressure medium which is delivered by the hydrostatic piston engine ().

Drive having an energy recovery and retarder function

The invention relates to a hydrostatic drive () and to a method of braking a hydrostatic drive (). In the hydrostatic drive (), in a closed circuit a hydraulic pump () is connected by a first and a second working line () to a hydraulic motor (). The hydrostatic drive () comprises a brake actuation device () as well as at least one pressure relief valve (), which is connected to the working line disposed downstream of the hydraulic motor (). The hydraulic pump () upon detection of an actuation of the brake actuation device () is adjustable to a braking delivery rate. The hydraulic motor () is adjusted in dependence upon the actuating intensity of the brake actuation device () in the direction of a larger absorption volume if the actuating intensity of the brake actuation device () increases.

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Ulm, Germany

Martin Behm