Zf Friedrichshafen Ag

Zahnradfabrik Friedrichshafen, Ag.

Wilhelm Härdtle

Friedrich J Ehrlinger

Manfred Schwab

Walter Frei

Gunter Schwarz

Peter Hartig

A shaft-gear connection comprises a shaft and a shrunk-on gear that has an axial first section, attached by a first shrink-fit bond, and an axial second section, attached by a second shrink-fit bond. The second shrink-fit bond is greater than the first shrink-fit bond so that a greater maximum torque to be transmitted from the gear to the shaft by the second shrink-fit bond than by the first shrink-fit bond. An axial intermediate section, attached by a third shrink-fit bond, is located between the axial first section and the axial second section. Both a surface pressure and a maximum torque that can be transmitted by the third shrink-fit bond are greater than the surface pressure and the maximum torque that can be transmitted by the first shrink-fit bond, but are less than the surface pressure and the maximum torque that can be transmitted by the second shrink-fit bond.

Shaft-gear connection

A method for the control of an actuator of a starting clutch of a motor vehicle. The actuator is so regulated by a control apparatus that the starting clutch is closed upon the presence of a desire for starting, as well as closed by an adjusted, transmission ratio, and the clutch is opened upon the termination of the starting procedure. For the freeing of a vehicle from a roadway obstruction by way of a rocking process of the vehicle, it is proposed that the starting clutch, during a starting procedure and by way of control of the actuation actuator, is operated in a fully automatic manner in such a way, that the torque (M_K) periodically varies.

Method for controlling an actuator of a starting clutch in the automatic transmission of a vehicle

An apparatus and a process for the prevention of the rollback of a vehicle with a vehicle braking system (), wherein a braking system () comprises a vehicle brake pressure modifying apparatus (); a device () which are enabled to recognize a forward movement of the vehicle, and a brake control apparatus (), which is connected to the vehicle brake pressure modifying apparatus () and the device (). There is generated in the control apparatus () a signal which, upon a standstill of the vehicle, activates a brake and sensor combination () which acts upon a transmission () of the vehicle, the brake and the sensor combination () being supplementary to the brakes of the vehicle brake system () and, upon a recognition of a forward motion of the vehicle, the braking fluid pressure in the vehicle brake pressure modifying apparatus () is reduced and thus the brake and the sensor combination () acting upon the transmission is released.

Preventing reverse creep in a motor vehicle

A vehicle gearbox () comprises a centrally operating device () for releasing the clutch (), which is provided between the clutch disc and the clutch bell housing of the gearbox (). A transmission control unit () provided on or in the gearbox () is both electrically connected directly with the device () and the medium for actuating the clutch () is received directly from the transmission control unit ().

Gearbox with central clutch release

Gearshift device for electrically controlled gearboxes

In a pressure-control device for affecting the closing behavior of powershift clutches (K.sub.1 -K.sub.X) in a powershift transmission, a regulating valve (1) cooperates with a damping device (2) as pressure-control valve. Chokes (4, 40, 400) for a more or less smooth connection are arranged in combination with pressure lines (P.sub.S, P.sub.R) over the pressure cycle when the clutch concerned (K.sub.1 -K.sub.X) is engaged. The travel of the damper piston (21) in a direction toward the regulating valve (1) is shortened by a pressurizing piston device (3) cooperating with the piston (21) of the damping device (2). Thus the time for the slipping phase in the engaged clutch concerned is shortened and, together with a higher initial pressure after the clutch is filled, the friction is limited. The limitation of the friction can also be obtained by adding a second choke in parallel in the control pressure line (Pr) by which the choked cross section is increased.

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Markdorf, Germany

Wilhelm Härdtle