Abstract: A brake triggering device for an elevator car actuates a pair of brake devices (13) disposed at opposite sides at a car structure (1) from a limiter cable (11) and an entraining lever (10) utilizing a trigger element (2). A small upward movement of the entraining lever (10) releases, by way of a Bowden pull (9) and a trigger mechanism (4), the trigger element (2) which is moved by a spring force to actuate the two brake devices (13) simultaneously. The trigger element (2) is constructed as a torsion spring and has a very short reaction time.
Abstract: An elevator safety based on having the elevator lift-rod, under the influence of the elevator governor, cause to rotate approximately elliptical cams, called quasi-elliptical cams. The cams are wider in one orientation, just as an ellipse has a major axis, wider than its minor axis. The cams are positioned to push against a brake pad as they rotate so that the major axis of each cam changes orientation with the minor axis. The cams can be shaped to simulate a wedge-type safety, even one using a wedge with multiple ramp angles. With essentially no additional complexity, the cam safety can be designed to operate with a bi-directional governor, one which exerts, usually through an intermediate linkage, force on the lift-rod in either the up or down motion depending on the unintended motion of the elevator.
Abstract: A brake assembly by means of which rotational motion and also linear motion, i.e. faulty motion of lifting platforms, especially dropping, is braked. The assembly comprises a braking gear (20, 21) fitted onto axle (4), a coupling (25, 26) to transmit rotational motion and furnished with a locking device (27) that releases by an adjusted rate of centrifugal force generated by the rotational motion and locks the coupling to transmit rotational motion between the axle and the locking device. Upon locking, the locking device in the coupling is fitted to transmit rotational motion also in the opposite direction of the direction produced by the locking device in order to open the locking device by turning axle (4) in the opposite direction, and the coupling has a retaining shoulder (50) to prevent the locking device from returning immediately to an unlocked position when the brake is opened by rotating axle (4) in the opposite direction.
Abstract: A governor for a moving device, such as an elevator, includes a primary assembly that generates a magnetic field and a secondary assembly extending through the generated magnetic field. The assemblies define a rotor and a stator that rotate at a relative speed that is proportional to the speed of the moving device. The stator is biased into a stationary position. If the relative rotational speed exceeds a predetermined limit, the bias on the stator is overcome by the interaction of the secondary assembly with the magnetic field. Movement of the stator away from the stationary position actuates an apparatus to prevent an overspeed condition of the moving device.
Type:
Grant
Filed:
January 26, 1996
Date of Patent:
August 25, 1998
Assignee:
Otis Elevator Company
Inventors:
Sanjay Kamani, John K. Salmon, deceased
Abstract: An elevator overspeed protection apparatus includes a brake apparatus which makes use of eddy currents. The brake apparatus includes a magnetic spring placed on a car in the proximity of a pickup of the elevator overspeed protection apparatus such that, when an arm of the brake apparatus is in a horizontal condition, a displacement of the pickup is prevented with a strong attracting force by the magnetic spring, but when the arm is inclined obliquely, the attracting force of the magnetic spring is prevented from acting upon the pickup. Due to the construction, the brake apparatus operates stably and with certainty and has an increased life.
Abstract: The overspeed governor is provided with a switch to disable the operation of the elevator motor. The apparatus includes a controllable actuator which resets the switch into a state enabling the operation of the elevator motor. The actuator is preferably a geared d.c. motor.
Abstract: Lifting apparatus comprising first and second generally vertical masts, an assembly including a frame moveable along the masts, and a load engaging mechanism mounted on the frame, a first brake mechanism which, upon actuation, engages the first mast to prevent downward movement of the frame relative to the first mast, a second brake mechanism which, upon actuation, engages the second mast to prevent downward movement of the frame relative to the second mast, an overspeed mechanism for sensing the downward velocity of the assembly and for actuating the first brake mechanism when the overspeed mechanism senses that the downward velocity of the assembly exceeds a predetermined value, a first electrical device for providing an electrical signal when the first brake mechanism is actuated, and a second electrical device for actuating the second brake mechanism in response to the electrical signal.
Abstract: A safety brake apparatus for a vehicle traveling in an elevator hoistway is provided, comprising a first link, a pair of second links, a connector rod, and an intermediate link. The first link is pivotly attached to a first side member of the vehicle. The connecting rod extends through the first and second side members, pivotly mounted within each side member. One of the second links is fixed to the connecting rod on the first side member side of the vehicle and the other second link is fixed to the connecting rod on the second side member side of the vehicle. The intermediate link is pivotly attached to both the first and second links on the first side member side of the counterweight. Each second link is connected to a safety brake. Actuating the first link causes the intermediate link to rotate the second links and therefore the connector rod, and causes the second links to actuate the respective safety brake.
Abstract: A safety brake (14) for an elevator (or other) car has a plurality of permanent magnets (21, 23) arranged along the car guide rail (13) with alternate magnets disposed with opposite polar orientation so as to provide loops of flux (23) between the magnets and in the guide rail when the brake is actuated. A pawl (27) engages a latch (30) to retain the brake lifted when not in use; a governor operated safety rod (34) rotates the pawl to disengage the latch for actuation of the brake in an emergency. Guides (55-59) stabilize the brake against the braking forces. A jack screw (49) overcomes attractive magnetic forces to reset the brake into the lifted position.
Abstract: An elevator apparatus having an easily mountable position detector and capable of detecting the position of a car with good precision. The apparatus has a position detector and a governor driven by a cable connected to an emergency stop device mounted on a car and capable of actuating the emergency stop device when the speed of the car has exceeded a prescribed speed, the position detector being driven by the governor, the apparatus includes a power transmission mechanism for causing rotation of the position detector at a speed higher than the speed of rotation of the governor.
Type:
Grant
Filed:
September 16, 1993
Date of Patent:
October 17, 1995
Assignees:
Hitachi, Ltd., Hitachi Building Systems Engineering & Services Co., Ltd.
Inventors:
Masakatsu Tanaka, Seinosuke Yahiro, Jun Sugahara, Satoru Sasaki
Abstract: An elevator includes a cab supported and guided by guide rails for travel along the guide rails. Emergency stop devices for stopping the travel of the cab are fixed to the cab. Mounted on the cab is a governor for actuating the stop devices when the traveling speed of the cab exceeds a predetermined speed. The governor includes a roller mounted on the cab and in rolling contact with one of the guide rails so that the roller rolls on the guide rail in interlocking engagement upon travel of the cab. A governor pulley is rotatably mounted on the cab and connected to the roller through a belt so as to rotate in interlocking cooperation with the roller. A safety Link mechanism is mounted on the cab and actuates the stop devices when the rotating speed of the governor pulley exceeds a predetermined speed.