Robert Boschgmbh

Achim Schreiber

Alfred Muller

Gerhard Eschrich

Manfred Schwab

Joseph Sauer

Meinrad Feder

Klaus Ries-Mueller

Joachim Luh

A method and apparatus for adjusting the torque output of a power train of a motor vehicle. An engine is connected to the input end of a continuously variable belt-type transmission. The output end of the belt-type transmission is operably connected to the drivable wheels of a motor vehicle. Open-loop torque control for the power train of the motor vehicle is effected based on specific operating states of the power train and the mechanical tension acting on the belt of the continuously variable belt-type transmission.

Method and device for adjusting a torque output of a power train of a motor vehicle

Reference values are stored for various conditions of gear shift operations of a vehicle motor of a particular type and model for various motor speed and load combinations, the reference values having a magnitude characterizing the gear shifting operation, for example the time interval required from the appearance of a gear shift command until the end of slip in a coupling indicates that the gear shift is complete. As the vehicle is driven, actual values of this magnitude are stored and averaged for a predetermined number of shift operations under the same class of condition. Correction values for the pressure of hydraulic fluid of the gear shift control, originally set at zero for all conditions, are determined by comparison of reference values with average actual values and stored. In subsequent driving, the stored correction values are used to control the pressure of the hydraulic medium to maintain a standard of comfort for all shift operations and new average actual values are used from time to time to modify the correction values for compensation of aging effects.

Method of controlling frictionally engageable couplings of an automatic

Method and apparatus for control of gear changing under load in a

The time required for shifting gears from an old to a new gear and the jolt created by the shift is decreased by initiating a known overlap of disengagement of the friction elements of the old gear and engagement of the friction elements of the new gear at the time the hydraulic unit operating the friction elements of the new gear is completely filled. Since a voltage pulse occurs across the solenoid winding of the pressure regulator when the hydraulic unit is completely filled, the solenoid valve is monitored by a threshold circuit which responds to the pulse. The output of the threshold circuit sets a flipflop. The flipflop is reset in response to a gear shift initiation signal furnished by a microprocessor. The microprocessor samples the flipflop output to determine whether the hydraulic unit is completely filled and initiates the overlap portion of the gear shift when this is so.

Gear shift control in motor vehicles with automatic transmissions

The hydraulic regulating device for an automatic transmission system in motor vehicles having a plurality of hydraulic couplings, includes a single pressure build-up regulating valve and a single pressure decrease regulating valve and assigned to each coupling a solenoid operated directional control valve having its working port connected to the couplings, its pressure port connected via a switch-on reversing valve to the pressure build-up regulating valve, and its return port connected via a switch-off reversing valve to a return conduit; both reversing valves are controlled according to predetermined pressure levels on the coupling so that in the working position of the switch-on reversing valve the coupling is connected to a stable high pressure and when the coupling process is initiated by reversing the position of the directional control valve, the switch-off reversing valve connects the coupling element to the pressure decrease regulating valve.

Hydraulic regulating device for load shifted gears

The invention pertains to a hydraulic control system for servos in automatic transmissions, which, in a known fashion, utilizes a main pressure valve to regulate the pressure within the control system and further utilizes a converter pressure valve to supply a hydrodynamic torque converter and the lubrication system. The servos (for example, the clutches) utilized in this type of automatic transmissions cooperate with electromagnetically actuated pressure regulating valves have a current-proportional response. These electromagnetic valves are actuated by electronic control signals generated by sensors which monitor various parameters during operation, making previously utilized sensors superfluous. By control of the pressure regulating valves the forward gear, the reverse gear or the neutral gear can be engaged in the simplest fashion. By means of a magnet valve associated with the main pressure valve the levels of pressure may be varied. It is also possible, via simple associated elements, to install an emergency system which during a failure of the electrical system allows the transmission to continue to operate.

Growing community of inventors

Schwieberdingen, Germany

Achim Schreiber