Otis Elevator Company

Edward E Ahigian

Richard E Kulak

Richard E Peruggi

Thomas He

Jerome F Jaminet

David W Barrett

Thomas M McHugh

Thomas M Kowalczyk

Zbigniew Piech

Frank Guliuzza, Jr

Thomas M Kowalcyk

When an elevator is running, the car door 27 is locked in the closed position by a brake shoe 12 which engages the edge of the door hanger 24 in response to a push-type solenoid 19 overcoming the force of a spring. When the door is not closed, a friction brake pad 11 contacts the door hanger surface to hold the door open for passenger boarding or to stop the door in case of failure of door operator power while the door is in motion.

Elevator door brake, brake, lock, and hold-open

An electronic motor drive produces a required motion profile for an elevator door operator actuated by a three-phase, line-powered linear induction motor (LIM) by means of an array of TRIAC switches producing selected forces from the LIM. The TRIAC drive is capable of producing acceleration, deceleration or free coast in either the open or close direction of door operation. When controlled by an algorithm such as a 'time-optimal switch point' or 'bang-bang' control, the TRIAC drive produces the required motions from the linear induction motor for elevator door operation. The motor windings may be switchable between delta and wye hookups to provide two distinct thrust levels. Phase angle modulation may be used to provide finer control of thrust. The linear motor may be a 12-slot arrangement having four poles and three phases and arranged with flux emanating from the stationary primary (on the car) to a stationary backiron part of the secondary also mounted on the car, wherein the flux passes through a movable copper part of the secondary attached to the elevator door and passing between the primary and the backiron.

Triac drive for three-phase line-powered linear induction motor elevator

A linear induction motor utilizes a double-sided primary and a dual secondary to directly drive an elevator car door open and closed. The invention has the advantage of being compact: all magnetic-attractive loads are confined to a primary mount bracket, and all thrust loads are carried directly by the car header, not transferred to the cab. Also, high thrusts can be developed from a small space, i.e., short net working coil area, due to the double-sided primary winding and dual secondary arrangement. The configuration is basically simple, with a low moving mass and easy-to-fabricate parts, the primary core being particularly easily wound.

Elevator door drive using dual secondary linear induction motor

An elevator door evacuation deterrent device in combination with a moving vane elevator door coupler having a pair of coupler vanes pivotally connected by links to form a parallelogram movable between a compressed position, an expanded interlock position and a third expanded overtravel locking position when the elevator car is outside a landing zone. A top end from one of the vanes projects upwardly and abuts a locking plate on the elevator car to limit movement of the car door in the overtravel locking position when the car is outside of a landing zone.

Elevator car evacuation deterrent device

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.

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

An elevator hoistway door lock assembly comprises first and second lock subassemblies. Each lock subassembly has a rotatable latch mounted on a respective door hanger, a first and second catches are mounted on the hoistway for engagement with each respective latch, a first and second cam followers are fastened to the respective latches and movable between a first position in which each latch engages the respective catch in a locked position and a second position in which each latch is disengaged from the respective catch in an unlocked position so that the hoistway doors may be moved to an open position and each pair of electrical contacts for indicating a locked condition of the respective door when the contacts are electrically connected.

Elevator hoistway door bolt lock

The door or doors on an elevator cab are driven during their opening and closing cycles by a linear induction motor drive system. The primary of the linear motor is fixed to the cab assembly, and the secondary is mounted on the door hanger panel and moves with the door. In order for the secondary to maintain a proper spacing relative to the primary, a flexible connection is provided between the secondary and the remainder of the door. In this way, shifting of the door during its opening and closing movements will not cause misalignment of the secondary with respect to the primary.

Elevator cab door drive system

An elevator door hold-close device in combination with a moving vane elevator door coupler having first and second vanes pivotally connected by links to form a parallelogram pivotally movable between a first compressed uncoupled position and an expanded coupled position. A structural member is fixed to the elevator car and has a friction pad configured for retentive engagement with a friction pad on the vane assembly to hold the car door closed against manual operation when the elevator car is in flight.

Elevator door coupling and hold-close apparatus

A coupling for causing an elevator car door to engage an elevator hoistway door includes a pair of vanes, each end of each vane pivoted on a link connecting it with the other vane, the links being disposed for rotation between said two vanes on an elevator car door thereby forming a parallelogram. The vanes extend vertically between four rollers which rotate about horizontal axles disposed at the top of the hoistway door, and which provide rotationally stiff coupling. A solenoid actuator can move one vane up to cause the parallelogram to shrink, into an uncoupled position. When the actuator is disenergized, a spring causes the parallelogram to spread so that the vanes are wedged between the rollers and the two doors are coupled together.

Stationary actuator moving vane elevator car door coupling

The door or doors of an elevator are driven through their opening and closing cycles by one or more linear induction motor (LIM) assemblies in which the primary winding component of the LIM assembly is secured to the elevator cab structure and the LIM secondary component is secured to the cab door. If the cab has two oppositely moving doors, there will preferably be two separate motor drives, one for each door. In one embodiment, the motor components are arranged so as to create a normal force which is horizontal; and in another embodiment, the normal force created is vertical. A primary motor mount bracket is used which secures the primary winding component to the overhead component of the cab structure.

Linear induction motor door drive assembly for elevators

Rotationally stiff elevator car door coupling

An elevator car door is moved by a variable voltage, variable frequency linear induction motor which is driven open current loop to achieve a desired velocity profile indicated by an incremental linear encoder, with washed out proportional and integral gain. A magnetizing current insufficient to overcome the weight of the door is added in quadrature with the linear force current, and frequency is determined open loop in a predetermined fashion. Pulse width modulation voltage control signals are utilized to apply fixed voltages of correct polarity through a low pass three phase filter to the windings of the motor for correct intervals of time so as to synthesize desired sinusoidal winding currents. A boost of current is provided following each zero crossing of the sinusoidal winding currents to overcome lags therein. A ramp down of voltage avoids dropping the door at the end of door opening and door closing.

Velocity regulated, open current loop, variable voltage, variable

Maintaining open loop current drive to linear induction motor

Smooth and quiet linear induction motor elevator door operation

A reciprocating elevator cab door is mounted on a guide track assembly which is fixed to the cab. The cab door is provided with guide rollers which travel along the upper surface of the guide track as the door opens and closes. The door is also provided with at least one upthrust roller which engages the lower surface of the guide track so as to stabilize the door against rocking motion as it moves back and forth over the guide track. The upthrust roller is preferably spring biased against the guide track. Use of the upthrust roller allows greater flexibility of door drive systems.

Growing community of inventors

West Hartford, CT, United States of America

Edward E Ahigian