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:
Dec. 08, 1987
Filed:
May. 14, 1986
Robert R Boldt, Taylor Ridge, IL (US);
East Moline Metal Products Company, East Moline, IL (US);
Abstract
To a controller utilizing thyristors have been added delayed resetting circuits connected to timing circuits for enabling delayed firing, and also circuits for inverting polarity of error signal in order to accommodate regenerative and reverse-plug braking. Other additional circuits include circuits for controlling a ramp generator for developing different segments of a ramp required for different modes of operation of a motor. Sequence switching circuits in the circuits controlling operation of the motor determine that full acceleration or deceleration of a selected mode is completed before a newly selected mode is started. For smooth starting and stopping of elevators, a curve-shaping circuit succeeding the ramp generator gradually changes the slope at the very ends of a selected segment of the ramp, and a brake control circuit having an input connected to the motor and output switching circuits for controlling disconnection of the motor and application of holding brakes, synchronizes disconnection of the motor and application of mechanical brakes when the motor ceases rotation.