US 12,231,072 B2
Encoderless motor with improved granularity and methods of use
Tien Phan, Sunnyvale, CA (US); and Doug Dority, Sunnyvale, CA (US)
Assigned to Cepheid, Sunnyvale, CA (US)
Filed by Cepheid, Sunnyvale, CA (US)
Filed on Jun. 26, 2023, as Appl. No. 18/341,280.
Application 18/341,280 is a continuation of application No. 17/217,926, filed on Mar. 30, 2021, granted, now 11,689,125.
Application 17/217,926 is a continuation of application No. 16/375,044, filed on Apr. 4, 2019, granted, now 10,972,025, issued on Apr. 6, 2021.
Application 16/375,044 is a continuation of application No. 15/217,893, filed on Jul. 22, 2016, granted, now 10,348,225, issued on Jul. 19, 2019.
Claims priority of provisional application 62/195,449, filed on Jul. 22, 2015.
Prior Publication US 2023/0421079 A1, Dec. 28, 2023
Int. Cl. H02P 6/16 (2016.01); H02K 1/27 (2022.01); H02K 1/2791 (2022.01); H02K 11/00 (2016.01); H02K 11/215 (2016.01); H02K 15/02 (2006.01); H02K 29/08 (2006.01); H02K 1/2786 (2022.01); H02K 21/22 (2006.01)
CPC H02P 6/16 (2013.01) [H02K 1/27 (2013.01); H02K 1/2791 (2022.01); H02K 11/0094 (2013.01); H02K 11/215 (2016.01); H02K 15/02 (2013.01); H02K 29/08 (2013.01); H02K 1/2786 (2013.01); H02K 21/22 (2013.01); H02K 2211/03 (2013.01); H02K 2213/03 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A DC electric motor comprising:
a stator mounted to a substrate, the stator comprising a coil assembly having a core of magnetic material and electrical windings;
a rotor mounted to the stator, the rotor comprising permanent magnets mounted to a cylindrical skirt and each extending to a distal edge; and
a plurality of sensors mounted to the substrate adjacent the permanent magnets, wherein a displacement of the motor is determinable from signals from the plurality of sensors;
wherein a clearance between the extended distal edge of each of the permanent magnets and the plurality of sensors is defined such that during operation of the motor, passage of the permanent magnets over the plurality of sensors produces a plurality of sinusoidal signals of varying voltages;
a processor module communicatively coupled with the plurality of sensors and configured to:
receive the plurality of sinusoidal signals from the plurality of sensors, during rotation of the rotor, to produce a signal pattern comprising an intersecting superimposition of the plurality of sinusoidal signals, each sinusoidal signal including one or more portions between crossing points of the signal pattern that are substantially straight line segments; and
determine a displacement of the motor based on at least one of the one or more portions between the crossing points of the signal pattern that are substantially straight line segments.