Patent ID: 11965757
Assignee: GUILIN GUANGLU MEASURING INSTRUMENT CO., LTD.
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 4:
5. The hybrid positioning electromagnetic induction displacement sensor according to claim 1, wherein the transceiver board (1) and the excitation board (2) may move relative to each other along a measurement axis; the transceiver board (1) is arranged with two transmitter windings (1.4, 1.5) extending along the measurement axis and three three-phase receiver windings (1.1, 1.2, 1.3) with different pitches; the first transmitter winding (1.4) separately encircles the three-phase receiver winding (1.1) with a pitch of P1 and the three-phase receiver winding (1.2) with a pitch of P2 by using two approximately closed rectangular coils (1.4.1, 1.4.2) in the same direction in series; the second transmitter winding (1.5) separately encircles the three-phase receiver winding (1.1) with a pitch of P1 and the three-phase receiver winding (1.3) with a pitch of P3 by using two approximately closed rectangular coils (1.4.1, 1.5.2) in the same direction in series; and the excitation board (2) is arranged with three rows of excitation coils (2.1, 2.2, 2.3) extending along the measurement axis, the three rows of excitation coils and the three three-phase receiver windings (1.1, 1.2, 1.3) on the transceiver board (1) having the same pitch and coincided center lines respectively, and a shape of the excitation coil is a rounded rectangular short-circuit loop; and
a spatial frequency difference between the pitches P2 and P1 is taken as a mid-pitch spatial frequency FM=1/P2−1/P1, to obtain a mid-pitch PM=1/FM=P1·P2/(P1−P2)=m·P1=(m+1)·P2 with a wavelength ratio of m; and a spatial frequency difference between the pitches P3 and P1 is taken as a coarse-pitch spatial frequency FC=1/P3−1/P1, to obtain a coarse pitch PC=1/FC=P1·P3/(P1−P3)=m·n·P1=(m·n+1)·P3 with a wavelength ratio of n.