US 12,237,781 B2
Ultrasonic motor, robot, and life diagnostic method of ultrasonic motor
Kiichi Kajino, Matsumoto (JP)
Assigned to SEIKO EPSON CORPORATION, Tokyo (JP)
Filed by SEIKO EPSON CORPORATION, Tokyo (JP)
Filed on Dec. 15, 2022, as Appl. No. 18/081,713.
Claims priority of application No. 2021-204006 (JP), filed on Dec. 16, 2021.
Prior Publication US 2023/0198426 A1, Jun. 22, 2023
Int. Cl. H02N 2/00 (2006.01); G01R 31/34 (2020.01)
CPC H02N 2/008 (2013.01) [G01R 31/343 (2013.01); H02N 2/0025 (2013.01); H02N 2/0065 (2013.01)] 5 Claims
OG exemplary drawing
 
1. An ultrasonic motor comprising:
a vibration section having a piezoelectric element configured to generate vibration by receiving a drive voltage;
a driven section;
a convex section connected to the vibration section and configured to transmit vibration of the vibration section to the driven section;
a drive circuit configured to generate the drive voltage;
an encoder configured to detect a movement amount of the driven section;
a storage section configured to store a specified voltage value; and
a determination section configured to receive position information from the encoder when the driven section starts to move and a voltage value from the drive circuit at time of start up and to determine that least one of the convex section or the driven section is worn out when the voltage value at the time of start up is larger than the specified voltage value.