Robert Boschgmbh

Ewald Stuible

Walter Berger

Friedrich Rabus

Gunter Grather

Rupert Fackler

Martin Pfau

Willi Kuehn

Christian Klein

Christian Schwientek

Ingo Mueller-Vogt

Bernd Gussmann

Robert Weiland

A method for regulating the current through an electromagnetic actuator. The actuator, a first switch and a current-measuring circuit form a series circuit. A free-wheeling diode is parallel-connected to the actuator. The first switch is closed and opened by a control and a pulse generator using a PWM signal (PWM=pulse width modulation) in such a way that the current flowing through the actuator and measured by the current-measuring circuit is regulated to a setpoint value (SW). The time duration of one on and off switching cycle of the PWM signal is altered, and a so-called dither function in the form of a low-frequency oscillation is superimposed on the PWM signal.

Method for regulating the current through an electromagnetic actuator

The invention proceeds from a system for detecting a condition of the wheels of a motor vehicle. For this purpose, means are provided for generating rpm signals, which represent the rotational movements of the wheels, and evaluation means, by means of which a signal is outputted in dependence upon the generated signals, which signal represents the display-relevant condition. The essence of the invention is that the evaluation means are so configured that, first, and dependent upon the generated rpm signals, first difference values are formed for the rpm differences of at least two vehicle wheels on the two sides of the vehicle. Depending upon a first comparison of the formed difference values to each other and/or to pregivable first threshold values, the signal, which represents a display-relevant condition, is outputted. With the invention, one obtains a very simple and cost-effective wheel condition detection (emergency wheel detection, tire air loss detection) which operates correctly also when the vehicle drives through a curve.

System for monitoring tire status

An error signal is generated in a motor vehicle with at least two wheels located on the right and left in the front and rear areas of the motor vehicle. This is accomplished by detecting signals representing the rotational speeds of the vehicle wheels. In addition, cornering is detected, depending on the signals detected in particular. The signals detected in cornering are then compared with an ideal cornering performance, whereupon the error signal is generated, depending on the result of the comparison. With the comparison, it is possible to detect by a simple method erroneous rotational speed sensor signals, e.g., due to transposition of the lines.

Process and device for generating an error signal in a motor vehicle

At certain operating points, a plausibility test of the detected rotational speed signals is used to recognize an existing defect. The operating point for implementing the plausibility test is determined when it is detected that the motor vehicle has accelerated. The operating point at which defects in speed sensors are detected is determined in a simple manner but in such a way that any defect which may be present can be recognized reliably.

Method for defect detection in rotational speed sensors

To accurately determine the dwell time as well as the ignition instant in a digitally controlled ignition system to provide essentially constant ignition energy to a spark plug, and permit ready adjustment and matching of a basic system to various types of internal combustion engines, a counter is controlled to count up at a rate depending on speed of the engine starting from a predetermined angular position of the crankshaft of the engine with respect to a piston, then count down at a second rate, which may be fixed; a fixed number is introduced into the counter which changes the count state during either the first or the second count cycle, or upon transition of counting from the first to the second count cycle, the determination of the number being readily changed by specific connection of output terminals from the counter to a decoding stage, thus avoiding the necessity of reconnecting the internal wiring of a group of gates to match the system to any given engine.

Growing community of inventors

Eberdingen, Germany

Ewald Stuible