Time-optimal control of an AC line-driven linear motor elevator door operator

US5682023A · kind A · utility

Assignee

• OTIS ELEVATOR COMPANY · US

Inventors

• Thomas M. McHugh · Farmington, US
• Richard E. Peruggi · Glastonbury, US
• Edward E. Ahigian · Arlington Heights, US
• Jerome F. Jaminet · South Windsor, US
• Thomas He · Unionville, US
• Thomas M. Kowalczyk · Farmington, US
• Richard E. Kulak · Bristol, US
• David W. Barrett · Hartland, US

Key dates

• Filing date: Sep 25, 1995
• Grant date: Oct 28, 1997
• Expiry date: Sep 25, 2015

Classification

• Technology area (CPC G): Physics
• CPC primary: G05B2219/41327
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A linear motor for operating an elevator door is energized using a bang-bang control strategy (10) wherein three-phase AC utility mains (16) are connected (29) directly to the linear motor primary (14) by means of a motor control (12) in response to control signals (26) provided under the direction of a control strategy (10), which may be microprocessor-based. Commands (24) from an elevator controller to open/close the elevator door cause the system to operate the doors and a sensor (22) provides feedback (28) by means of which the control (10) is able to determine switch points for switching the AC mains.