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:
Sep. 25, 2001
Filed:
Jun. 14, 1999
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A method of controlling a mounting unit having a shaft operated under servo control using a current driven actuator, comprises the steps of detecting interrruption of the servo control, and switching from a positioning control mode to a constant current control mode for supplying an constant amount of current to the shaft actuator to suspend the shaft. In an embodiment the method further includes engaging a gripping device, for holding the shaft, so as to keep the shaft from free-falling when interruption of the servo control is detected, and maintaining the constant current control mode at least until the gripping device grips the shaft. Still further, the current control mode optionally includes the steps of maintaining the supply of the constant amount of current for a predetermined period of time, and disengaging power supplied to the actuator after the predetermined period of time has elapsed.