In a method for determining the reset time in a pressure sensor that detects the pressure in a combustion chamber of an internal combustion engine and emits a corresponding pressure signal, with the pressure curve in the combustion chamber having at least one high-pressure region the reset time is determined as a function of at least one pressure value detected in the high-pressure phase, so that it is possible, within the sensor, to determine a favorable time at which to reset the drift, based on the pressure range In the method according to the invention, information about the auxiliary rotation speed is determined based on the pressure curve of the compression phase and is then used to generate the reset time, the method entails only slight circuitry-related expense and can therefore be implemented even in an ASIC without complex signal processing, and it functions in almost all known engine operating states.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view showing a typical pressure curve over time,
FIG. 2 is a view showing shows a flow chart of the process, and
FIG. 3 is a view showing schematically a device according to the exemplary embodiment of the invention.
Claims
1. A method for determining a reset time in a pressure sensor that detects a pressure in a combustion chamber of an internal combustion engine and emits a corresponding pressure signal, in which a pressure curve in the combustion chamber has at least one high-pressure region, the method comprising the steps of detecting at least one pressure value during a high pressure phase; and determining a reset time as a function of the at least one pressure value detected during the high-pressure phase.
2. A method as defined in claim 1, wherein said determining the reset time includes determining the reset time in such a way that during the high-pressure region a time between two predetermined values of the pressure signal is detected and the reset time is determined as a function of this time between the two predetermined values of the pressure signal.
3. A method as defined in claim 2; and further comprising multiplying the detected time between the two predetermined values of the pressure signal by a factor (F_mult) at an additional time; said determining the reset time including determining the reset time after the pressure signal has reached a second predetermined value and the additional time has expires.
4. A method as defined in claim 2; and further comprising multiplying the detected time between two predetermined values of the pressure signal by a factor (F_mult) at an additional time, said determining the reset time includes determining the reset time after the pressure signal has reached a second predetermined value, the additional time has expired, and the pressure signal has fallen before a third value.
5. A method for drift compensation of a pressure sensor that detects the pressure in a combustion chamber of an internal combustion engine and emits a corresponding pressure signal, in which a pressure curve in the combustion chamber has at least one high-pressure region and a reset time is determined for the drift compensation, wherein the reset time is determined as a function of at least one pressure value detected during a high-pressure phase s defined in claim 1.
6. A device for executing a method for determining a reset time in a pressure sensor that detects a pressure in a combustion chamber of an internal combustion engine and emits a corresponding pressure signal, in which a pressure curve in the combustion chamber has at leas tone high-pressure region, the method comprising the steps of detecting at least one pressure value during a high pressure phase, and determining a reset time as a function of the at least one pressure value detected during a high-pressure phase.
7. A device for executing a method for drift compensation of a pressure sensor that detects the pressure in a combustion chamber of an internal combustion engine and emits a corresponding pressure signal, in which a pressure curve in the combustion chamber has at least one high-pressure region and a reset time is determined for the drift compensation, wherein the reset time is determined as a function of at least one pressure value detected during a high-pressure phase for a drift compensation.
Patent Application
20070192044
