US 12,222,226 B2
Variable reluctance position sensor
Juha Pyrhönen, Lappeenranta (FI); Chong Di, Lappeenranta (FI); and Ilya Petrov, Lappeenranta (FI)
Assigned to LAPPEENRANNAN-LAHDEN TEKNILLINEN YLIOPISTO LUT, Lappeenranta (FI)
Appl. No. 17/927,845
Filed by LAPPEENRANNAN-LAHDEN TEKNILLINEN YLIOPISTO LUT, Lappeenranta (FI)
PCT Filed May 24, 2021, PCT No. PCT/FI2021/050373
§ 371(c)(1), (2) Date Nov. 25, 2022,
PCT Pub. No. WO2021/240059, PCT Pub. Date Dec. 2, 2021.
Claims priority of application No. 20205541 (FI), filed on May 27, 2020.
Prior Publication US 2023/0221148 A1, Jul. 13, 2023
Int. Cl. G01D 5/20 (2006.01); G01B 7/00 (2006.01)
CPC G01D 5/2046 (2013.01) [G01B 7/003 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A variable reluctance position sensor comprising:
a first element comprising a plurality of magnetic sensor sections equidistantly successively, and
a second element moveable with respect to the first element and comprising an air-gap surface having a periodically meandering profile with at least two spatial meandering periods,
wherein:
each of the magnetic sensor sections is configured to conduct a magnetic flux to and from the second element via the airgap surface of the second element, and
the magnetic sensor sections comprise excitation coils, first detection coils configured to produce a first alternating output signal when alternating excitation signal is supplied to the excitation coils, and second detection coils configured to produce a second alternating output signal when the alternating excitation signal is supplied to the excitation coils, amplitudes of the first and second alternating output signals being dependent on a position of the second element with respect to the first element so that envelopes of the first and second alternating output signals have a phase-shift with respect to each other,
wherein a number N of the magnetic sensor sections of the first element is:
N=1+n P2/P1,
where P1 is a spatial shift between successive ones of the magnetic sensor sections, P2 is the spatial meandering period of the profile of the airgap surface of the second element, P2/P1 is an integer greater than one, and n is a positive integer.