Abstract: A method and an arrangement are provided for monitoring the safety of a counterweighted elevator. In the method, an elevator car is driven with a hoisting machine towards the top end of the elevator hoistway, contact between the counterweight and the end buffer of the elevator hoistway is determined, a reference point for the location of the elevator car is registered when detecting contact between the counterweight and the end buffer, the distance that the elevator car travels onwards from the aforementioned reference point for the location is measured, and if the distance traveled by the elevator car onwards from the aforementioned reference point exceeds a threshold value a signal indicating a risk of slackening of the traction rope is formed.

Abstract: An elevator system is a one-shaft double-car elevator system and includes a floor-recognition abnormality detector to detect, with respect to one of the cars, a floor recognition abnormality that at least one of a car position and floor information cannot be normally recognized, a terminal-floor driving mechanism to make, on the basis of a notification of floor-recognition abnormality information detected by the floor-recognition abnormality detector, the other one of the cars travel to a terminal floor in a direction opposite to a direction toward the one of the cars, and a floor-recognition-abnormality correcting-operation mechanism to perform, on the basis of terminal-floor traveling information from the terminal-floor driving mechanism, a floor-recognition-abnormality correcting-operation to correct the floor recognition abnormality of the one of the cars; therefore, an operation to recover from the abnormality can be safely performed without collision of the cars.

Abstract: An elevator includes at least one elevator car driving along an elevator shaft as well as an elevator control measuring the car position. The elevator further includes a buffer in the shaft pit, whose length is adjustable in response to the car position and car speed. Via this measure, the shaft pit can be reduced in high speed elevator requiring large buffer lengths.

Abstract: An elevator system includes a car traveling up and down along a hoistway; a buffer for stopping the car at an end of the hoistway; brakes for braking travel of the car; a car traveling-information acquisition mechanism for acquiring information as to speed of the car; and a brake control unit for controlling the brake by comparing a speed of the car with a speed pattern curve created based upon a speed curve of the car when braking force is forcedly exerted by the brakes to enable the buffer to absorb a shock at the collision of the car with the buffer to a level below a predetermined specified value.

Abstract: The invention relates to an elevator system and also to a method for monitoring the movement an elevator car. In the method a first emergency braking procedure is activated for braking the elevator car at a first deceleration if the speed of the elevator car exceeds the first limit value for permitted speed, and also a second emergency braking procedure is further activated for braking the elevator car at a second deceleration that is greater than the first, if the speed of the elevator car exceeds the second limit value for permitted speed that is greater than the first limit value for permitted speed.

Abstract: The safety device according to the invention for operator protection in elevators with a low-height shaft bottom (5), is characterized in that it uses a brace (1) hinged on abase plate (3) secured to the bottom of the shaft (5) and arranged when folded in the horizontal position at a reduced height above the shaft bottom (5) in normal elevator operation, and a buffer element (9) secured underneath the car (11) and adapted to come into contact with a horizontal side surface of the brace (1) in its folded position, wherein said brace (1) is adapted to be moved by an appropriate lifting device (31) to a vertical lifted position in which the buffer element (9) can come into contact with an upper surface (15) of the brace (1), in a condition where the operator can work in the shaft bottom (5), wherein the length of the 15 brace added (1) to the thickness of the buffer element (9) provides for a sufficient depth between the underside of the car (11) and the shaft bottom (5) to suppress any risk for the operator to

Abstract: An elevator system in which a controller monitors whether or not a speed of an ascending/descending body reaches a preset overspeed. At a time of maintenance work, a stopper is interposed between a buffer and the ascending/descending body to limit a lowered position of the ascending/descending body. Stopper detection means detects installation of the stopper onto at least one of the buffer and the ascending/descending body. When the stopper is detected by the stopper detection means, the controller lowers a set value of the overspeed.

Abstract: An elevator car position measuring system includes a strip having a code mark pattern mounted near the elevator car and parallel to a travel direction, a code reading device mounted on the elevator car for contactless scanning of the code mark pattern and an evaluating unit connected to the code reading device for evaluating the scanned code mark pattern. A code word is formed by “n” successive code marks of the code mark pattern, a plurality of different ones of the code words are unambiguously arranged in an n-digit pseudo random sequence, the code words form a single-track of the code mark pattern and each of the code words represents an absolute car position. A floor sensor mounted on the elevator car detects position markings at floor levels along the travel direction and is connected to the evaluating units for evaluating the detected position markings against said scanned code words.

Abstract: An elevator system in which an elevator-car and a counter weight are suspended on a pulley system in a hoistway. The elevator system includes a receiving unit for receiving an electric power from a feeding unit provided in the hoistway, an inverter for converting the received electric power into ac power, a motor connected to an ac side of the inverter for driving the counter weight in up and down directions, a sensor for detecting a position of the receiving unit, and a control unit for controlling an inverter on the basis of the position detected by the position sensor. The counter weight carries the receiving means, the inverter, and the motor.

Abstract: The elevator safety device creates a false pit beneath the elevator frame using left and right laterally-spaced, fixed stop members fixedly attached to the car frame, and left and right laterally-spaced safety columns affixed to the pit floor and pivotable between an extended position in vertical alignment with the left and right stop members, respectively, and a retracted position clear of the car, the frame, and the left and right stop members. The safety columns are bumper-type devices designed to support full car weight should the need arise, and provides the ASME A17.1 minimum depth of pit for the refuge area. Actuators are operatively connected to the safety columns to pivot them between their extended and retracted positions. A pressure-sensitive detector located on the pit floor below the car detects the presence of a person on the pit floor. The actuators are electronically activated to pivot the safety columns from their retracted to their extended positions.

Abstract: A normal terminal stopping device (NTSD) using terminal zone position checkpoint detection with a binary coding method to identify a checkpoint within a terminal zone, and a digital shaft encoder mounted on the shaft of the hoist motor to determine a car position relative to a target stopping point. A microprocessor-based controller is used to compare a velocity command signal to a velocity limit reference. If the velocity command exceeds the velocity limit, the NTSD functions will take over to cause the elevator car to decelerate at the NTSD rate. In particular, the velocity limit reference is computed according to lead compensation and curve shaping techniques to attain better drive tracking characteristics of the motion controller. Binary coded checkpoints are used to eliminate error introduced in a car position derived from a motor shaft digital encoder.

Abstract: An emergency terminal speed limiting device (ETSLD) uses terminal zone position checkpoint detection with a binary coding method for the sensible stationary part mounted in the terminal zone. Instead of using three separate stationary vanes of different lengths as cams for actuating three separate switches on the car as they pass by the cams, only two vanes are needed. They can be of shorter length, e.g. equal length, and overlapped in a central part of the terminal zone to create three distinct subzones to thereby create a sensible binary coded subzone indicator. The boundaries of the subzones can be used as position checkpoints. Material and manpower for installation are thereby reduced. The stationary part need not be vanes but could take other forms such as reflective tape. Likewise, the moving sensor part can be other than a cam-operated switch, such as an optical transceiver.

Abstract: 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.

Abstract: An apparatus for generating function signals to an elevator controller for controlling an elevator car (1) at terminal landings in a building includes an upper cam (3) and a lower cam (4) for mounting on a wall (2a, 2b) in an elevator shaft (2) at a top landing and a bottom landing respectively, an upper switch (5) and a lower switch (8) for mounting on the elevator car and for connection to a source of electrical power (12) and an interface circuit (10) connected to the switches. The interface circuit (10) has a lower limit relay coil (16), an upper limit relay coil (27), normally closed up relay contact sets (17,19,35) and normally closed down relay contact sets (24,28,30) which cooperate with the switches (5,8) for generating upper and lower limit function signals to control car travel and upper and lower slow down signals to control car speed.

Abstract: A method for performing a correction run by an elevator system having an elevator car following a loss of an elevator car position information includes: detecting a terminal landing magnet in response to the loss of the elevator position information; moving the elevator car away from a predetermined terminal landing until the terminal landing magnet is not detected; running the elevator car toward the predetermined terminal landing in response to not detecting the terminal landing magnet in said moving step; detecting two magnets simultaneously in response to running the elevator car toward the predetermined landing terminal; stopping the elevator car in response to simultaneously detecting the two magnets; and resetting the elevator position information in response to said stopping step.

Abstract: An elevator system includes a CPU to dictate speed signals during a normal elevator car run, and a normal terminal stopping device (NTSD) to dictate maximum allowable speeds approaching the top and bottom terminal floors. The NTSD system normally operates in monitor mode, where the NTSD profile has the same deceleration rate as the normal speed dictation signals. Should the normal speed dictation signal exceed the NTSD value, the NTSD system switches to a violation mode, having a rate of deceleration greater than the normal deceleration.A plurality of vanes are located in the hoistway to provide absolute position signals for generating NTSD values. Preferably, when operating in the monitor mode, the NTSD software calculates pseudo checkpoints between the actual vanes, to readjust the NTSD values. Also, preferably the NTSD values during jerk into deceleration are calculated based on the constant deceleration rate during slowdown.

Abstract: An elevator safety device in which a counterweight cam is attached to the counterweight and top terminal landing final limit switches are disposed below the bottom terminal landing of the hoistway so that it is operated by the counterweight cam. The top terminal landing final limit switches only need to be provided in accordance with the counterweight buffer stroke, regardless of to what extent the car has been flung upward, with the result that fewer final limit switches are required.