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:
Mar. 18, 2014
Filed:
Nov. 15, 2012
Panasonic Corporation, Osaka, JP;
Masatoshi Atsumi, Shiga, JP;
Kenichirou Inagaki, Osaka, JP;
Hiroyuki Kaizo, Kyoto, JP;
Tadashi Arimura, Kyoto, JP;
Yutaka Yamada, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A speed-changing device includes a motor, a reduction gear train that reduces a rotation speed of the motor in accordance with a speed reduction ratio and transmits the rotation at the reduced speed, and a speed reduction ratio switching unit that switches the speed reduction ratio. The speed reduction ratio switching unit includes an actuator that switches the speed reduction ratio, a controller that controls the actuator, and a drive state detector that detects an index value representing load torque applied to the motor. The controller activates the actuator when the index value exceeds a first threshold value and activates the actuator when the index value fluctuates between the first threshold and a second threshold thereby forming an undulated pattern that satisfies a predetermined condition.