Otis Elevator Company

Otiscelecator Company

Gunter Blechschmidt

Peter L Herkel

Alberto Vecchiotti

Michael Mann

Christoph M Ernecke

Stefan Spannhake

Robert Oesterle

Peter Walden

Michael Bernhard Kocur

Wolfgang Lutz Zemke

Method for controlling the drive of a conveyor device ( ), especially in the form of an escalator or moving sidewalk, switchable between load operation and no-load operation, having a drive motor ( ) and a frequency changer ( ) controllable at least with respect to frequency and phase position of its output voltage, in which the drive motor ( ) in load operation is fed with a line voltage with essentially constant line frequency and in no-load operation with the frequency changer output voltage, the phase difference between the phase position of the line voltage and the phase position of the frequency changer output voltage is determined, the phase position of the frequency changer output voltage is corrected according to the determined phase difference and therefore essentially brought into agreement with the phase position of the line voltage and switching is produced as soon as this agreement is reached.

Switch over from the mains supply to a frequency converter by a phase correction process for an escalator drive

A method of adjusting an elevator speed comprising the steps of determining a desired creep period, determining an actual creep period, determining a difference between the desired creep period and the actual creep period, determining a deceleration time for minimizing the difference between the desired creep period and the actual creep period, and adjusting the elevator speed in response to the deceleration time.

Deceleration time for an elevator car

An elevator drive fault detector for detecting operational faults in an elevator drive having an inverter and only one circuit breaker includes a current sensor, a monitoring device, a control device and an operational control system. The current sensor provides a current sensor signal. The monitoring device determines if an operational fault exists in response to the current sensor signal and provides an operational signal. The monitoring device disables the operational signal if the monitoring device determines that an operational fault exists or if the elevator drive fault detector performs a system check operation. The operational control system provides both the run command and an operational check signal and is responsive to the operational signal such that if the operational signal is disabled then the operational control system opens the one circuit breaker and disables the run command such that the control device disables a PWM signal. If the operational signal was disabled during a system check operation then the operational control provides the operational check signal to the monitoring device such that if the monitoring device does not receive the operational check signal within a predetermined time then the monitoring device continues to disable the operational signal and the drive is elevator shutdown.

Elevator drive fault detector

Growing community of inventors

Berlin, Germany

Gunter Blechschmidt