Otis Elevator Company

Herbert K Horbruegger

Ismail Agirman

Mustapha Toutaoui

Peter L Herkel

Bernd L Ackermann

Dirk Heinrich Tegtmeier

Michael Mann

Ralph S Stripling

Reinhard Henkel

Stephan Glessner

Markus Mueller

Mario Sanz Abia

Kristian Bernhard Wittjen

Jost-Ingo Eichberger

Daniel Diaz-Lopez

Virgilio Valdivia Guerrero

Method for monitoring at least part of a comb-line () of a comb plate () having a plurality of teeth (), of a people conveyor () having a movable transportation band () and the comb plate () located at the transition () between the movable transportation band () and the stationary comb plate (), wherein the method includes (a) taking a picture of the comb-line () with a camera (); (b) comparing the picture with a reference picture; (c) determining the safety state of the comb-line () based on such comparison.

Optically monitoring comb-line of escalators and moving walks

Method for performing an elevator rescue run in an emergency situation, the elevator comprising and elevator car, a counter weight, a rope suspending the car and the counterweight, a drive motor, an emergency brake for stopping the car in an emergency situation, and a motor drive unit for supplying drive power to and for controlling the drive motor, having the following rescue run sequence steps:

Method for performing an elevator rescue run

Automatic and manual adjustment of a new elevator system installation is accomplished by means of a service tool for interacting with software resident in the elevator system whereby various control parameters such as the feed forward gain of the drive system, the start time delay for delaying initiation of a start torque profile for bypassing the velocity loop during starting, the polarity of the feedback signals, e.g., armature current, velocity, motor field current, and other parameters, may be adjusted automatically, while others, such as the impedance of an elevator brake, may be adjusted by a technician responding to automatic prompts.

Adjusting technique for a digital elevator drive system

The invention concerns an open-look speed control device for an induction motor to drive an elevator cabin, approaching a premarked where braking must be initiated point in advance of stopping at a marked point at a floor level to be approached at a creep speed, and for a VVVF inverter, which supplies current to the induction motor. The current supplied to the induction motor, is measured when the cabin travels at constant speed prior to reaching the premarked point. A slippage compensation unit determines a pertinent slippage frequency from the measured active current, and from it derives the frequency specification for the upcoming creep phase. A memory stores a function that indicates creep time as a function of the measured active current. A computer unit calculates a delay time for the next run from the measured creep time. The start of the cabin's deceleration process is delayed, according to a lookup function, and after the car stops a new virtual updated creep time is again 'measured' by turning from the stopping of dictated deceleration until the actual end of the creep process.

Delayed start of elevator car deceleration and creep using VVVF

A current regulator phase controls a power signal to control silicon controlled rectifiers arranged in a bridge. The silicon controlled rectifiers excite a generator field of an elevator drive. Discontinuity in the generator field current, caused by the inductive load and latching and holding currents in the silicon controlled rectifiers, is detected to provide an analog discontinuity signal. The analog discontinuity signal is converted to digital form and used to dynamically alter the gain and response of the regulator.

Adaptive digital armature current control method for ward-leonard

Start jerk and acceleration overshoot on elevator starting are reduced by bypassing and delaying application of an elevator closed loop velocity control system. A bypassing starting torque increases the torque of the motor before the onset of motion, at which time the starting torque is leveled off and held constant and the velocity speed reference profile is started. A small creep velocity dictation injected into the closed velocity loop in addition to the starting torque command causes the difference between the speed profile and the sensed speed to be very small during starting. Moreover, by selecting lift brake current in such a way as to promote a smooth brake opening and by selecting an increasing starting torque profile which overcomes the declining brake torque just after the brake begins to open, the torque needed to compensate for the load can be evenly balanced with the release of brake torque. The timing of initiation of the starting torque may be selected according to a time delay which may vary between different installations and be adjustable in order to obtain zero rollback when the elevator car first moves. A step decrease in the starting torque may be dictated upon detecting system movement in order to compensate for the transition from static friction to sliding friction. The rate of increase of starting torque is preferably exponential.

Growing community of inventors

Berlin, Germany

Herbert K Horbruegger