Robert Boschgmbh

Klaus Hahn

Peter Burk

Eberhard Schnaibel

Erich Schneider

Erich Junginger

Gerhard Kolberg

In a method for tolerance compensation of a position signal (W) of a position transducer, which has two mechanical end stops, first and second end values (W1, W2) of the position signal that are assigned to the two end stops and are stored in a read-write memory. Starting values (W1S, W2S) are stored in a read-write memory of the evaluation circuit and are set within the tolerance limits of the actual signal (Wd) detected by the position transducer. The starting values (W1S, W2S) are initially taken over as the ned values (W1, W2) into a read-write memory and cyclically compared with the actual or detected position signal (Wd). If a stored end value (W2) is exceeded by the detected position signal (Wd) or if within a predetermined time period (P) no position signal above the stored end value (W2) has been detected, the position signal is taken over as a new end value (W2) into the read-write memory, and the previous value is erased. The position signal is referred to a reference value ascertained from the two end values (W1, W2) and converted into a standardized output position signal (U).

Method for tolerance compensation of a position transducer

Driving-speed adjusting arrangement

The invention is directed to a method for triggering switching functions in which the latter are triggered when the position signal emitted by a position transmitter exceeds or falls below a predeterminable signal level, the position signal being corrected and scaled in a signal-processing arrangement. A precise, long-term stable correspondence of the predeterminable signal level to a definite position of the position transmitter is assured in that the end values of the position signal corresponding to the two end stops are ascertained in a learning algorithm after each time the position transmitter is put into operation. The method is particularly suitable for triggering switching functions in a motor vehicle which has a position transmitter as a desired-value transmitter of an engine performance control or regulating system, the position transmitter being mechanically connected to the accelerator pedal of the vehicle. The triggering of the kick-down function, for example, for controlling the transmission of the vehicle occurs after a position of the accelerator pedal has been passed, the position always being located the same spacing ahead of the full-load stop. Mechanical tolerances and aging processes have no influence on this correspondence.

Method for triggering a switching function

To allow for apparatus tolerances, aging of equipment, and changes in operation, for example due to changes in temperature, in a closed-loop servo system in which an operator-controlled fuel supply control element (1) provides, via a coupled command control transducer (2), a signal to control a positioning motor (8) which moves a fuel supply control element (9, 29) in accordance with deflection of the operator control panel, a logic and calculating element, in form of a microprocessor (3) is provided, included in the control loop. When the fuel control element, for example a throttle in the induction pipe of an Otto-type internal combustion engine (ICE) or a fuel injection controller of a Diesel engine reaches a predetermined limiting position, for example no-load idling, or full-load wide-open position, and engages a corresponding stop (12, 14; 212, 214), the microprocessor provides a test or monitoring signal which algebraically differs from that which a command signal should have when the fuel control element is at the respective position. The test signal is changed, in linear steps, towards the condition at which an error signal within the servo loop becomes zero or null; the value of the test command signal is stored at that time and used as a compensation or added, algebraically, to the transduced command signal from the command control transducer (2), or interpolated with respect to the other limiting position to derive an interpolation characteristic, thereby modifying the transduced command signal, so that the actual position of the fuel supply control element will be that desired by the operator controlling the operator-controlled controller (1).

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Buhlertal, Germany

Klaus Hahn