Zahnradfabrik Friedrichshafen, Ag.

Zf Friedrichshafen Ag

Helmut Eymuller

Egon Mann

Eduard Heilig

Gerhard Buck

Powershift reversing transmission

Failsafe brake system for a motor vehicle, in particular for a

Drive device with gearbox

Engine-rpm-dependent arrest device to prevent non-permitted down shifts

Driving mechanism with two speed clutch

Compact hydraulic drive mechanism for wheel assemblies

Each wheel of a road roller is provided with a drive which has a hydraulic motor with a radial output shaft coupled to the drive shaft of the wheel by bevel gearing. At one side of the housing containing the bevel gearing and the hydraulic motor, a brake is provided for the drive shaft whose opposite end is connected by a toothed coupling to the sun gear shaft of a planetary gearing transmission in a second housing disposed at least in part within the wheel. A flange of this transmission is connected to the planet carriers and to the wheel to rotate the latter.

Travelling drive for road rollers, more particularly with vibratory

In a cement-mixer truck having a mixing drum rotated via a step-up transmission by a hydrostatic motor in turn energized by a power pump driven by the vehicle engine, the motor is disposed in a chamber at least partially filled with coolant replenished by leakage from the power pump and the motor and by oil from a valve housing supplied via a pressure-regulating and a bleeding valve respectively tapping high-pressure and low-pressure pumping conduits of a hydraulic circuit. The motor coolant chamber is surrounded by an oil reservoir connected at an output via an internal filter and a second engine-driven pump to the hydraulic circuit for feeding oil thereto and at an input via a heat exchanger to the motor chamber for drawing hot fluid from the motor bath, the reservoir serving in part to reduce noise from the hydraulic motor. A ventilating fan at the heat exchanger and a water pump are driven directly by the same shaft that is connected to the step-up transmission.

Hydrostatic-mechanical drive for vehicular cement mixers

A wheel-mounted drive system usable for a sprocket wheel of a chain-drive vehicle has a nonrotatable two-part housing adapted to be mounted directly and substantially immovably on the vehicle frame. A hydraulic motor is mounted in one part of this housing and has a motor output extending through the other part of the housing which contains a transmission whose input is connected to the motor output and whose output is directly connected to the drive wheel and to a brake. A bearing rotatably mounts the transmission output directly on the housing. The brake can be pressurized through axial passages extending through the main shaft of the motor. The transmission includes planetary gearing, and the motor, transmission, and output member are all rotatable about the same central axis.

Wheel-mounted hydraulic drive system

Growing community of inventors

Friedrichshafen, Germany

Helmut Eymuller