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:
Nov. 03, 1987
Filed:
Jan. 26, 1983
Applicant:
Inventor:
Isao Sasao, Inazawa, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
B66B / ;
U.S. Cl.
CPC ...
187134 ;
Abstract
An elevator cage travel detector includes an apertured disc 8 whose rotational movement is sensed by a photo encoding pulse generator 9 which produces two phase displaced outputs 10b, 11b. To prevent motion detection errors due to false generations of one of the pulse outputs when the cage is at rest, due to vibrations or the like, each pulse train is fed to both its own flip-flop 14C, 14D and to a leading and trailing edge detector 14A, 14B whose output enables a flip-flop for the other pulse train. The further processing of the two pulse trains is thus mutually dependent upon the continuing generation of both of them.