Robert Bosch

Rolf Reischl

Claudius Bevot

Klaus Mueller

Axel-Werner Haag

Klaus Joos

Guenther Hohl

Hubert Stier

Norbert Keim

Werner Jundt

Markus Amler

Thomas Frenz

Matthias Boee

Wolfgang Ruehle

Andreas Eichendorf

Bernhard Ledermann

Norbert Schneider

Wolfgang Kosak

Manfred Strohrmann

Ulf Pischke

Juergen Eckhardt

Benjamin Sillmann

Joerg Brueckner

Hans Loistl

Thomas Classen

Marco Neuscheler

Thomas Schulz

Ralf Kraemer

Andreas Kuehn

Andreas Gess

Frank Engelke

Karl Wenzel

Metin Guerer

Andreas Pschera

A method for determining a temperature of a gas flowing past a sensing element, the sensing element being situated in or on a housing. The method includes reading in a sensing element signal and a housing signal, the sensing element signal representing a temperature of the sensing element and the housing signal representing a temperature of the housing. The method also includes ascertaining the temperature of the gas using the sensing element signal, the housing signal and a thermal resistance of the housing as a function of a material and/or a shape of the housing.

Method and device for determining a temperature of a gas flowing past a sensing element

A circuit system for measuring a sensor element capacitance of a sensor element, in particular of a capacitive humidity sensor, including: the sensor element, which has the sensor element capacitance; a charge storage element, which is connected directly, or only via a resistor element, in series to the sensor element; and a control unit, which is configured to charge the charge storage element to a reference voltage and to successively transfer the charge via the sensor element capacitance until the charge storage element has reached a particular comparison voltage, the sensor element number of transfer processes thus ascertained representing information about the sensor element capacitance of the sensor element.

Circuit system for measuring a sensor element capacitance

In a method for operating a heatable exhaust-gas sensor, which supplies at least one measuring signal and in which a sensor heater is operated using a pulse-width modulated operating voltage, the detection of the at least one measuring signal has priority over the supply of the pulse-width modulated operating voltage for sensor heater, and at least during a predefined time window in which the measuring signal is detected, the supply of the pulse-width modulated operating voltage for the sensor heater is suppressed using a blocking signal.

Method and devices for operating a heatable exhaust-gas sensor

A method for determining a polarization of a pump cell and/or a Nernst cell of a lambda probe for the diagnosis of the broadband lambda probe. A voltage or current pulse is applied to the pump/Nernst cell in a first method task, and, in a second method task, a voltage at the pump cell and/or the Nernst cell, or a variable that is related to the polarization or its time characteristic is determined and used as a measure of the polarization, and the function of the broadband lambda probe is monitored via the ascertained polarization. The determination of the polarization may be performed as a voltage measurement performed once or multiple times, or by determining the effect of the polarization in an associated controller, such as a pump current controller of an engine control unit. The variable associated with the polarization may be the reaction of the pump current control.

Method for monitoring a broadband lambda probe

Methods for detecting the type of lambda probes having at least two electrodes disposed on and/or in a solid electrolyte, of which at least one electrode is separated from a gas mixture by a diffusion barrier, and a pump current Ip being applied to at least one of the electrodes. Either the internal resistance of the lambda probe between the electrodes is determined and the type of probe is inferred on the basis of this resistance, or currents are impressed between the electrodes and the type of probe is inferred based on the voltages or resistance ratios thereby resulting.

Method for detecting the type of lambda probes

In a method and with a circuit for operating a nitrogen oxide sensor for determining the nitrogen oxide (NOx) concentration in a gas mixture, in particular in post-treatment of an automotive exhaust, an electric pumping voltage (U_APE,IPE) which induces a pumping current (I_pump) being applied between an internal pump electrode (IPE) and an external pump electrode (APE) of a pumping cell, by which a constant oxygen partial pressure is established in a first test gas space by pumping oxygen in or out, the pumping voltage (U_APE,IPE) being regulated so that a constant voltage value is established at electrodes of a concentration cell, a NOx-sensitive third electrode situated in a second test gas space being operated as the second pumping cell in which a limit pumping current is established, indicating the NOx concentration, in order to minimize the influence of oxygen on the nitrogen oxide signal measured, the pumping current (I_pump) is switched off or reduced in a controlled manner within a measurement time window (T_Mess) and the NOx concentration is determined within the measurement time window (T_Mess).

Nitrogen oxide sensor with attenuated oxygen dependence of the NOx signal

A measuring device, with a digital interface for the transmission of digital signals to an evaluation unit, is disclosed, whereby the interface includes a clock input, to which a system clock signal is fed, a signal input, to which a measured signal is applied, an arithmetic unit, which derives an output signal from the clock signal and measured signal, and a signal output where the output signal is output and transmitted to the evaluation unit. Measurement accuracy may be improved by transmitting a reference signal that is a signal derived from the clock signal, and using this reference signal to correct the output signal.

Measuring system with ratiometric frequency output

In an internal combustion engine, the fuel enters at least one combustion chamber of the internal combustion engine via at least one fuel injection device. A piezoelectric actuator moves a valve element of the fuel injection device. The function of the piezoelectric actuator is monitored and a malfunction is detected. To minimize the risk of damage to the internal combustion engine in the event of a malfunction of the piezoelectric actuator, the fuel mass flow to the fuel injection device is reduced if a malfunction of the piezoelectric actuator is detected.

Method and control and regulating device for operating an internal combustion engine with piezoelectrically actuated fuel injection valves

A method and device for triggering a solenoid valve for injecting fuel into an internal combustion engine is described. The triggering phase of the solenoid valve is subdivided into a pull-up phase and a holding phase. During the pull-up phase, a valve needle of the solenoid valve is caused to open by a first current intensity flowing through a magnetic coil of the solenoid valve. During the holding phase, the valve needle is held in the open state by a second, lower current intensity flowing through the magnetic coil. At least once at the beginning of the pull-up phase, a booster phase is activated during which a pulse-shaped booster current from a booster capacitor charged to a high voltage flows through the magnetic coil. During the triggering phase of the solenoid valve, a plurality of booster pulses are activated in succession, whose time position within the triggering phase is freely selectable.

Method and device for triggering a fuel injector

A method of metering fuel with a fuel injector, in particular a fuel injector for fuel injection systems in internal combustion engines is described, having a piezoelectric or magnetostrictive actuator and a valve closing body which is operable by the actuator with a valve lift, cooperating with a valve seat face provided on a valve seat body to form a sealing seat. The valve lift may be adjusted variably as a function of a variable control signal triggering an actuator to produce a variable fuel flow at the sealing seat. To produce afitted curve, the fuel flow of the fuel jet sprayed by the fuel injector is measured as a function of the control signal to produce a fitted curve, and a predetermined fuel flow is set with the control signal by using the fitted curve.

Method of metering fuel using a fuel injector

The invention is directed to a current regulator for an electromagnetic load used in conjunction with an internal combustion engine. The regulator produces positive and/or negative currents flowing through an electromagnetic load. In this arrangement, the two potentials present at a precision resistor that is connected in series with the load are adjusted to freely selectable values. To obtain both positive and negative currents, the current defined by the voltage drop occurring along the precision resistor is provided by a bridge circuit made up of four current-controlling arrangements. Allowance can be made for particular operating conditions of the current regulator simply by presetting desired values.

Current regulator for an electromagnetic load utilized in conjunction

The invention is directed to a method and an apparatus for controlling the air-fuel ratio of the operating mixture supplied to an internal combustion engine. The apparatus includes an oxygen sensor that is responsive to the oxygen content of the burnt operating mixture. The operating state of the sensor is detected by superposing a constant reference quantity on the oxygen sensor output quantity. The resultant of these quantities is fed to at least two comparators having different thresholds. The comparator outputs are processed to detect the operational readiness of the sensor. In this arrangement, the air-fuel ratio of the operating mixture is adjustable in dependence on the output quantity of the comparator to which the higher threshold is applied. This upper threshold and the special course of the Lambda sensor output voltage coact to compensate for the lean shift of the Lambda control during the warm-up phase of the internal combustion engine. In addition, this method largely avoids the transient response behavior of the control apparatus referred to as 'idle hunting' without necessitating additional circuit configurations. The use of the higher one of the two thresholds as the control threshold results in a significant improvement of the behavior of the internal combustion engine during the warm-up phase.

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Stuttgart, Germany

Rolf Reischl