US 12,132,359 B2
Electric actuator
Takamitsu Suzuki, Zama (JP); Kei Sato, Zama (JP); and Masaya Furushou, Zama (JP)
Assigned to NIDEC TOSOK CORPORATION, Kanagawa (JP)
Filed by Nidec Tosok Corporation, Zama (JP)
Filed on Aug. 22, 2022, as Appl. No. 17/892,210.
Claims priority of application No. 2021-134810 (JP), filed on Aug. 20, 2021.
Prior Publication US 2023/0055495 A1, Feb. 23, 2023
Int. Cl. H02K 11/21 (2016.01); H01H 3/26 (2006.01); H02K 7/00 (2006.01); H02K 7/14 (2006.01); H02K 11/30 (2016.01)
CPC H02K 11/30 (2016.01) [H01H 3/26 (2013.01); H02K 7/003 (2013.01); H02K 7/14 (2013.01); H02K 11/21 (2016.01)] 8 Claims
OG exemplary drawing
 
1. An electric actuator to switch a shift position, the electric actuator comprising:
a motor;
an output shaft to be driven by the motor;
a detent plate fixed to the output shaft and including valley portions including a first valley portion corresponding to a parking position provided on one end side in a circumferential direction and a second valley portion corresponding to a non-parking position provided on another end side in the circumferential direction;
an elastic portion including a contacted portion to be brought into contact with any one of the valley portions by an elastic force generated by rotation of the detent plate;
a first rotation sensor to detect a first rotation angle that is a rotation angle of the motor;
a second rotation sensor to detect a second rotation angle that is a rotation angle of the output shaft; and
a controller to control the motor based on detection results of the first rotation angle and the second rotation angle; wherein
when an abnormality occurs in the second rotation sensor, the controller is configured or programmed to execute:
abutting the contacted portion on a first side wall portion located on one end side in the circumferential direction of the first valley portion in the detent plate by rotating the motor;
acquiring, as a side wall position angle, the first rotation angle detected by the first rotation sensor when the contacted portion abuts on the first side wall portion;
a reverse rotation process of reversely rotating the motor to an angle at which the first rotation angle corresponds to a target rotation angle with reference to the side wall position angle; and
a stationary determination process of determining that the contacted portion is stationary at the parking position when the first rotation angle detected by the first rotation sensor continues to fall within a first tolerance having the target rotation angle as a reference value within a first predetermined time.