US 12,140,498 B2
Method for authorising updating of a magnetic sensor for a combustion engine with immunity to magnetic disturbances
Denis Bouscaren, Toulouse (FR)
Assigned to Continental Automotive GmbH, Hannover (DE)
Appl. No. 17/432,274
Filed by Continental Automotive GmbH, Hannover (DE)
PCT Filed Feb. 25, 2020, PCT No. PCT/EP2020/054921
§ 371(c)(1), (2) Date Aug. 19, 2021,
PCT Pub. No. WO2020/173947, PCT Pub. Date Sep. 3, 2020.
Claims priority of application No. 1901954 (FR), filed on Feb. 26, 2019.
Prior Publication US 2022/0252484 A1, Aug. 11, 2022
Int. Cl. G01D 5/12 (2006.01); G01D 5/244 (2006.01); G01M 15/06 (2006.01)
CPC G01M 15/06 (2013.01) [G01D 5/24438 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A method for authorizing an update of a switching threshold of a magnetic-field sensor for an internal combustion engine of a motor vehicle, for use with a target comprising an alternating succession of teeth and recesses being associated with an element of the internal combustion engine, the method comprising:
detecting, by the magnetic-field sensor, magnetic-field variations induced by a passage of the teeth of the target in proximity to the sensor by:
generating, from said variations, a magnetic signal exhibiting oscillations each having an amplitude comprised between a maximum and a relative minimum, certain of the oscillations being due to high-frequency external magnetic disturbances and not taking into account the high-frequency external magnetic disturbances in the update of the switching threshold by the sensor, wherein the high-frequency external magnetic disturbances comprise any external magnetic disturbance frequency higher than a maximum oscillation frequency at any engine speed, said maximum oscillation frequency being computed from a calibratable predetermined speed of rotation of the engine,
recomputing the switching threshold depending on a detected amplitude of at least two consecutive magnetic-field oscillations, and
comparing an oscillation frequency computed between said at least two consecutive oscillations to the maximum oscillation frequency computed based on a maximum speed of rotation of the engine and on a number of teeth on the target,
suspending the update of the switching threshold when the oscillation frequency is higher than the maximum oscillation frequency, and
providing an immunity of the sensor to the high-frequency external magnetic disturbances based on the recomputed switching threshold.