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:
Jul. 21, 1992
Filed:
Feb. 07, 1991
Masamoto Mizuno, Inazawa, JP;
Masanori Tawada, Inazawa, JP;
Terumi Hirabayashi, Inazawa, JP;
Toshiyuki Kodera, Inazawa, JP;
Abstract
A system for controlling operation of an elevator car door includes a torque command output device for outputting a torque command for controlling a car door driving motor on the basis of a difference between a speed command commanding the operating speed of the motor and the actual speed of operation of the motor, a door position detector for detecting the position of the car door in terms of the number of pulses in a pulse train produced by an encoder connected to the motor, and a memory for storing torque limit values as a function of the door position. The system also has a controller which reads the torque limit value corresponding to the car door position detected by the door position detector. The controller then compares the read torque limit value with a torque command output from the torque command output device and generates a reversing instruction to be given to the motor upon determining that the torque command is not smaller than the torque limit value. An obstruction of the door is sensed as a rise in the torque command so that the car door is reversed to ensure safety.