Zf Friedrichshafen Ag

J&uuml;rgen Legner

Egon Mann

Eduard Heilig

Siegfried St&uuml;tzle

In order to reduce the shock that occurs in downshifting and up-shifting a hydraulic radial piston engine, a valve ( ), which controls the displacement of the radial piston engine, is reversed with throttling. In order to prevent the throttled reversal from being affected by the level of pressure in the hydraulic fluid intake ( ) to the hydraulic radial piston engine, a sealing point is provided in the valve ( ), which controls the hydraulic fluid intake ( ) to the torque-generating pistons. To prevent critical safety situations from arising, a valve ( ) is positioned in front of the valve ( ) that controls the displacement of the hydraulic radial piston engine; this valve ( ) always switches the valve ( ) that controls the displacement of the hydraulic radial piston engine, without pressure, when the hydraulic fluid intake ( ) from a hydraulic fluid source to the hydraulic radial piston engine falls below a certain pressure level.

Hydraulic radial piston motor

A reversing transmission shiftable under load in which the reversing clutches ( ) are automatically evacuated by the flow of pressure medium through the clutch ( ) not subjected to pressure wherein bores ( ), which in this shifting state, are connected to the oil reservoir ( ) are placed at the highest point of the piston chamber. The shifting clutches ( ) are configured as negative clutches. For modulating the pressure during a reverse shift, an accumulator ( ) is provided from which pressure medium flows out via orifices ( ). For inching a valve ( ) is provided via which the closed clutch ( ) can be subjected to a pressure whose level can be continuously varied.

Reversing gear-box which can be shifted when under load

A traveling mechanism having a driving motor (,) which drives a feed pump (,) and a hydrostatic variable displacement pump (,), a zero fluctuating hydrostatic variable displacement motor (,) which forms with the hydrostatic variable displacement pump (,) a hydrostatic circuit and a hydrostatically driven 2-speed gear mechanism (,) which is engaged when the torque to be transmitted is minimal and the hydrostatic variable displacement motor (,) is at zero displacement capacity.

Growing community of inventors

Friedrichshafen, Germany

Jürgen Legner

Growing community of inventors

Friedrichshafen, Germany

J&uuml;rgen Legner

Jürgen Legner