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:
Jan. 28, 1992
Filed:
May. 01, 1991
Applicant:
Inventor:
Masashi Yonemoto, Aichi, JP;
Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B66B / ;
U.S. Cl.
CPC ...
187109 ; 187 89 ;
Abstract
A safety device for an elevator which detects a trouble of the control device quickly to apply an emergency brake, thereby to ensure the safety of the people in the cage. The elevator safety device is so designed that the harmonic wave component produced by an inverter is detected with the aid of a band-pass filter, and when the harmonic wave component thus detected becomes abnormal, an emergency stop instruction is produced.