Control device for an A.C. elevator
Patent 4471855 Issued on September 18, 1984. Estimated Expiration Date: 
July 30, 2002. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
July 30, 2002. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesCommutation circuit for a converter Rectifiers Elevator control apparatus Operation control apparatus for AC motors AC/DC or DC/AC Converter system with improved AC-line harmonic reduction System for bridging brief network failures Patent #: 4379325 InventorApplicationNo. 06/403873 filed on 07/30/1982US Classes:187/296, Limited to power source (i.e., motor) utilizing A.C. power318/803, With controlled a.c. to d.c. circuit in inverter supply363/69In parallelExaminersPrimary: Truhe, J. V.Assistant: Duncanson, W. E. Jr. Attorney, Agent or FirmInternational ClassesH02M 5/458 (20060101)H02M 5/00 (20060101) Foreign Application Priority Data1981-08-04 JPAbstractThis invention is designed to prevent the large charging current from flowing to the capacitor at the start of the elevator for preventing damage of the elements of the rectifier device. Thus the present device provides a control device for an a.c. elevator which includes:a commercial a.c. source,a capacitor for smoothing the output voltage of the commercial a.c. source,an inverter for converting the smoothed output voltage of the capacitor into an a.c. power of the variable frequency,an a.c. motor for driving the elevator car by the a.c. power supplied from said inverter, anda rectifier for rectifying the voltage of the commercial a.c. source and charging said capacitor by the thus rectified voltage at least when the car is stopped. | |
