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:
May. 22, 2001
Filed:
Apr. 13, 1999
Tetsuaki Kato, Hadano, JP;
Soichi Arita, Oshino-mura, JP;
Fanau Ltd., Yamanashi, JP;
Abstract
A method of and apparatus for detecting an abnormal load on a servo gun axis, capable of quickly detecting sticking of a welding tip to an object of welding before movement of a robot, without adversely affecting the object. A load applied to a servomotor for driving a welding tip of a welding gun is detected by an observer. An abnormal load signal is output when the estimated disturbance load deviates from a range defined by a reference &bgr; (&bgr;>0). A determination as to whether or not the estimated disturbance load is larger than the reference value +&bgr; is not made during a period of time from the start of a closing motion of the welding gun until the estimated disturbance load becomes smaller than a set value &agr;. When the welding tip is stuck to a workpiece, a negative estimated disturbance load smaller than −&bgr; is derived and an abnormal load Signal is outputted.