Robert Boschgmbh

Georg Pfaff

Gerhard Sohner

Gerd Hohne

Werner Jundt

Manfred Mezger

Bernd Bodig

Wolfram Bauer

Markus Klausner

Heinz Decker

Helmut Schmied

Johannes Artzner

Karl Seeger

Bernd W Kalkhof

Rainer Erhardt

Karl-Heinz Adler

Herbert Keller

Reinhard Leussink

Thomas Jokh

A method for recording data from parameter values captured using sensors in a vehicle, particularly for the reconstruction of accidents, as well as a memory device and a device for recording such data, it being possible to record all relevant data continuously using low memory volume, and to save it permanently in a short period of time. For this purpose, the parameter values and/or data calculated from them are recorded at increasing time intervals for the instantaneous capturing point in time at decreasing density. A suitable storage device has a RAM (random access memory) for recording the data in each case over a certain time space and in a nonvolatile memory (such as EEPROM), to which the recorded data can be transmitted in parallel from the RAM within a few ms. An ASIC is suitable for its implementation.

Method and device for recoding vehicle data

Method and circuit for monitoring the functioning of a sensor bridge

Device for ascertaining a rate of rotation

A countdown counter (14) counts out a speed dependent number to determine the start of the dwell period when a comparison number (Z17) is reached which is adjusted dynamically by a regulation counter (17). The countdown counter's contents are reduced by a value dependent upon acceleration when acceleration is present in order to improve the dynamic correction. In the case of strong accelerations these dynamic corrections are insufficient and when such a strong acceleration occurs the regulation counter content is set to a high value to assure a succession of strong ignition sparks. The high value of acceleration necessary for this precaution may be determined by comparing the difference of successive engine speed counts with a predetermined value or it may be determined by the failure of the current in the ignition coil primary to reach some predetermined value. After the generation of strong sparks is thus assured, the comparison count value provided by the regulation counter gradually returns to normal by the operation of the provisions for normal accommodation to dynamic conditions.

Dwell period control for engine ignition

An overvoltage protection circuit is galvanically, directly connected across at least part of the secondary winding in the ignition system of an internal combustion engine. The input portion of the overvoltage protection circuit is a voltage divider preferably constituted by RC elements. The voltage at the tap of the voltage divider is applied to a Schmitt trigger. When the voltage across the secondary winding becomes excessively high, the Schmitt trigger output pulse triggers a monostable multivibrator whose output pulse in turn increases the conductivity of a transistor switch located in series with the primary. The increase in primary current tends to oppose further increases in primary and secondary voltages. Alternatively, the output from the multivibrator could be used to shorten the time of current flow in the primary winding in subsequent ignition time intervals or to completely block any subsequent ignition process.

Ignition coil with overvoltage protection connected to the secondary

To improve an ignition system as described in U.S. Pat. No. 4,176,645, Jundt et al., in which a threshold switch is provided which controls current flow through the ignition coil, the turn-ON point of the current flow being determined, in part, by an integrator, and to prevent malfunction due to corroded terminals, improper installation and the like, a variable resistance branch, including a transistor 66, is connected across the integrator 31, 44, and so connected that, as the supply voltage drops, the effect of the integrator 31, 44 on the threshold switch 15, 16 is decreased, thus preventing modification of the inherent threshold level of the threshold switch by the action of the integrator. The transistor 66 in the variable resistance circuit 64 may be connected as a comparator, having its base connected to a junction J at fixed voltage (Zener diode 68, resistor 69), which is compared with the emitter-collector voltage, connected across the integrator 31, 44, and simultaneously changing its resistance value as the comparison is effected.

Ignition system for an internal combustion engine

The voltage across a capacitor is changed in a first direction while the current in the primary winding of the ignition coil increases to a predetermined value less than the value required for ignition and is thereafter changed in a second direction until ignition takes place. The voltage across the capacitor is applied to the inverting input of a difference amplifier constituting a threshold stage controlling the initiation and termination of current flow through the ignition coil. The two changes are symmetrical when the engine speed remains constant. The residual voltage across the capacitor at the end of the second change is maintained until the start of the next subsequent first change, so that the time at which the threshold stage switches in, that is the time at which primary current starts to flow in the ignition coil changes as a function of the residual voltage in the capacitor.

Ignition system with improved temperature and voltage compensation

Growing community of inventors

Markgroeningen, Germany

Georg Pfaff