# US 11,112,277 B2 · Camshaft or crankshaft sensor for automotive vehicle and diagnostic method for such a sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,112,277 B2 - Document ID: US11112277B2 - Status: Granted - Kind: B2 - Application number: 15/531,338 - Filed: 2015-11-26 - Published: 2017-11-09 - Granted: 2021-09-07 - Earliest claimed: 2014-11-28 - Assignees: Continental Automotive France; Continental Automotive GmbH - Applicants: Continental Automotive France; Continental Automotive GmbH - Inventors: David Mirassou; Marie-Nathalie Larue; Yann Dinard; Olivier Marle - Web page: https://patentgrep.com/patent/US11112277B2 ## CPC - G01D 5/24476: {Signal processing (G01D5/2448 - G01D5/24495 take precedence)} - G01D 1/12: giving a maximum or minimum of a value - G01D 3/028: mitigating undesired influences, e.g. temperature, pressure - G01D 5/24495: {using previous values} - G01D 18/00: Testing or calibrating apparatus or arrangements provided for in groups G01D1/00 - G01D15/00 - G01D 5/145: {influenced by the relative movement between the Hall device and magnetic fields (see G01R33/06)} - G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR ## Abstract Disclosed is a camshaft or crankshaft sensor including a toothed target, a measuring cell adapted to supply a raw signal and a processor module having two modes of operation: 1) a measurement mode in which the processor module is adapted to supply an output port of the sensor a measurement signal representing the times of passage of the teeth of the target at the level of the measuring cell; and 2) a diagnostic mode in which the processor module is adapted to supply at the output port of the sensor a diagnostic signal different from the measurement signal and representing the amplitude of the raw signal. Also disclosed is a method and a module for diagnosing such a sensor. ## Claims ### Claim 1 A motor vehicle camshaft or crankshaft sensor (10), said sensor comprising: a toothed target (11); a measuring cell (12) that supplies a raw analog signal corresponding to variations of a magnetic field induced by a rotation of the toothed target (11); an output port; and a processor module (14), connected to the output port and the measuring cell (12), that processes the raw signal received from the measuring cell (12), the processor module (14) configured to operate in either of two distinct operating modes, a first of the operating modes being a measurement mode and a second of the operating modes being a diagnostic mode, the processor module (14) further configured to switch between operating in the measurement mode and the diagnostic mode in response to receiving a predefined message for configuring the processor module (14), wherein in the measurement mode, the processor module (14) processes the raw signal and supplies at said output port (17) a measurement signal representing times of passage of teeth of the target (11) at a level of the measuring cell (12), and wherein in the diagnostic mode, the processor module (14) supplies at said output port (17) a diagnostic signal, different from the measurement signal and representing amplitudes of the raw signal. ### Claim 2 (depends on 1) The motor vehicle camshaft or crankshaft sensor (10) according to claim 1, wherein the processor module (14) is adapted to switch from the measurement mode to the diagnostic mode in response to reception of the predefined message at one of the output port (17) of the sensor and an electrical power supply port (15) of the sensor. ### Claim 3 (depends on 1) The motor vehicle camshaft or crankshaft sensor (10) according to claim 1, wherein in the diagnostic mode of operation the diagnostic signal corresponds to one or more local maxima values and/or local minima values of the raw signal. ### Claim 4 (depends on 3) The motor vehicle camshaft or crankshaft sensor (10) according to claim 3, wherein in the diagnostic mode of operation the diagnostic signal corresponds to a value of a last local maximum identified and/or a value of a last local minimum identified. ### Claim 5 (depends on 1) The motor vehicle camshaft or crankshaft sensor (10) according to claim 1, comprising only three ports: said output port, a power supply port for supplying operative energy to the sensor (10), and a reference port for connection to ground, wherein the processor module is adapted to be configured to switch between operating in the measurement mode and the diagnostic mode in response to receiving the predefine message from one or more of the electric power supply port, the reference port, and the output port. ### Claim 6 (depends on 1) The motor vehicle camshaft or crankshaft sensor (10) according to claim 1, further comprising: a power supply port for supplying operative energy to the sensor (10); and a reference port for connection to ground, wherein the processor module is adapted to be configured to switch between operating in the measurement mode and the diagnostic mode in response to receiving the predefine message from one or more of the electric power supply port, the reference port, and the output port. ### Claim 7 (depends on 1) The motor vehicle camshaft or crankshaft sensor (10) according to claim 1, wherein in the measurement mode, the measurement signal supplied by the processor module (14) to the output port (17) is a pulse signal consisting of pulses that correspond to a temporal representation of the geometry of the periphery of the toothed target (11), and wherein in the diagnostic mode, the amplitudes of the raw signal are represented by the diagnostic signal as values of local maxima and of local minima of the raw signal, correspondent to deformations of the teeth of the target (11). ### Claim 8 (depends on 1) The motor vehicle camshaft or crankshaft sensor (10) according to claim 1, wherein in the diagnostic mode, the amplitudes of the raw signal represented by the diagnostic signal consist in local maxima values of local maxima of the raw signal, generated by analog-to-digital conversion. ### Claim 9 A method (50) of diagnosing a motor vehicle camshaft or crankshaft sensor (10), comprising: a step of providing a sensor for sensing a presence of a tooth of a toothed target that rotates with the camshaft or crankshaft, the sensor having each of a measuring cell (12) that supplies a raw analog signal corresponding to variations of a magnetic field induced by a rotation of the toothed target, an output port (17), and a processor module (14), connected to the output port and the measuring cell (12), that processes the raw signal, the processor module (14) configured to operate in either of two distinct operating modes, a first of the operating modes being a measurement mode and a second of the operating modes being a diagnostic mode, the processor module (14) further configured to switch between i) operating in the measurement mode in which the processor module (14) supplies at said output port (17) a measurement signal representing times of passage of teeth of the target (11) at a level of the measuring cell (12), and ii) operating in the diagnostic mode in which the processor module (14) supplies at said output port (17) a diagnostic signal, different from the measurement signal and representing amplitudes of the raw signal; a configuration step (51) of sending a predefined message to the processor module (14) to cause the processor module (14) to operate in the diagnostic mode; a recurrent recovery step (52) of recovering the diagnostic signal at the output port (17), the diagnostic signal corresponding to a value of a local maximum and/or a local minimum of the raw signal; and a diagnostic step (53) of diagnosing the sensor (10) by comparing the diagnostic signals recovered at the output port of the sensor. ### Claim 10 (depends on 9) The method (50) according to claim 9, wherein the recurrent recovery step (52) is executed at particular times as a function of a predefined maximum value of the rotation speed of the target so as to recover in one rotation of the target values of the local maxima and/or local minima corresponding to each of the teeth of said target. ### Claim 11 (depends on 9) The method (50) according to claim 9, wherein the recurrent recovery step (52) is executed at particular times as a function of an estimate of a real rotation speed of the target so as to recover in one rotation of the target values of the local maxima and/or the local minima corresponding to each of the teeth of said target. ### Claim 12 (depends on 9) The method (50) according to claim 9, wherein, in the recurrent recovery step (52), the diagnostic signal corresponds to a value of the local maximum of the raw signal, and wherein during the diagnostic step (53) the sensor (10) is determined to be faulty if a ratio between a maximum value and a minimum value of the local maxima of the raw signal is greater than a predefined threshold value. ### Claim 13 (depends on 9) The method according to claim 9, wherein, during the configuration step, the predefined message is received via either of the outlet port and an electrical power supply port (15) for supplying operative power to the sensor. ### Claim 14 A diagnostic module (40) for diagnosing a camshaft or crankshaft sensor (10), comprising: means for interfacing with an output port of the camshaft or crankshaft sensor (10); and processing means having a memory connected thereto, said processing means configured to perform functions of transmitting a message via the output port to a processor module (14) of the camshaft or crankshaft sensor (10) that causes said processor module (14) to switch from operating in a measurement mode in which the processor module (14) supplies at said output port a measurement signal representing times of passage of teeth of a target at a level of a measuring cell (12) to a diagnostic mode in which the processor module supplies at said output port a diagnostic signal, different from the measurement signal and representing an amplitude of a raw analog signal produced by the measuring cell, recurrently recovering the diagnostic signal from the output port and storing the diagnostic signal in the memory, so as to recurrently store a plurality of diagnostic signals corresponding to a value of a local maximum and/or a local minimum of a raw signal generated by the sensor, and comparing the diagnostic signals. ### Claim 15 (depends on 2) The motor vehicle camshaft or crankshaft sensor (10) according to claim 2, wherein the diagnostic signal corresponds to one or more local maxima values and/or local minima values of the raw signal. ### Claim 16 (depends on 14) The module for diagnosing a camshaft or crankshaft sensor according to claim 14, wherein the processing means recurrently stores a plurality of diagnostic signals corresponding to a value of the local maximum of the raw signal generated by the sensor (10), and wherein the processing means determines that the sensor (10) is faulty if a ratio between a maximum value and a minimum value of the local maxima of the raw signal is greater than a predefined threshold value. ### Claim 17 An electronic sensing apparatus for sensing a position of a toothed target (11) that rotates with an operative rotation of a machine, the apparatus comprising: a measuring cell (12) that detects variations in a magnetic field inducted thereupon by rotation of the toothed target (11); an output port; and a processor module (14), connected to the output port and the measuring cell (12), that processes a raw analog signal received from the measuring cell (12), the processor module (14) configured to operate in either of two distinct operating modes, a first of the operating modes being a measurement mode and a second of the operating modes being a diagnostic mode, the processor module (14) further configured to switch between operating in the measurement mode and the diagnostic mode in response to receiving a predefined message for configuring the processor module (14), wherein in the measurement mode, the processor module (14) processes the raw signal and supplies at said output port (17) a measurement signal representing times of passage of teeth of the target (11) at a level of the measuring cell (12), and wherein in the diagnostic mode, the processor module (14) supplies at said output port (17) a diagnostic signal, different from the measurement signal and representing amplitudes of the raw signal. ### Claim 18 (depends on 17) The electronic sensing apparatus according to claim 17, comprising only three ports: said output port, a power supply port for supplying operative energy to the apparatus, and a reference port for connection to ground, wherein the processor module is adapted to be configured to switch between operating in the measurement mode and the diagnostic mode in response to receiving the predefine message from one or more of the electric power supply port, the reference port, and the output port. ### Claim 19 (depends on 17) The electronic sensing apparatus according to claim 17, further comprising: a power supply port for supplying operative energy to the apparatus; and a reference port for connection to ground, wherein the processor module is adapted to be configured to switch between operating in the measurement mode and the diagnostic mode in response to receiving the predefine message from one or more of the electric power supply port, the reference port, and the output port. ### Claim 20 (depends on 17) The electronic sensing apparatus according to claim 17, wherein the processor module (14) is adapted to switch from the measurement mode to the diagnostic mode in response to reception of the predefined message at one of the output port (17) of the sensor and an electrical power supply port (15) for supplying operative energy to the apparatus.