The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 14, 2020
Filed:
Apr. 03, 2017
Topcon Corporation, Tokyo, JP;
TOPCON CORPORATION, Tokyo, JP;
Abstract
Provided is a method for controlling an ultrasonic motor to reduce deterioration of automatic tracking performance, and a surveying instrument for the same. The present invention provides a method for controlling an ultrasonic motor in a surveying instrument including a rotary shaft, an ultrasonic motor that drives a rotary shaft, a tracking unit that includes a light emitting unit and a light receiving unit and tracks a target, and a clock signal oscillation unit that outputs a clock signal, wherein at the time of low-speed rotation of the ultrasonic motor, based on the clock signal, a ratio of an acceleration period in which a drive signal is applied and a deceleration period in which the drive signal is stopped in a drive cycle of the drive signal of the ultrasonic motor is set, and the light emitting unit is made to emit light in the deceleration period.