Abstract: A control valve assembly for an hydraulically operated elevator includes separate control valve units for controlling upwards and downwards movements of the elevator. The up valve unit is connected to a pump output and controls connection of the pump output to the elevator cylinder via a check valve. The up valve unit includes an orifice for connecting the pump output to a reservoir, and a valve member for varying the size of the orifice to control the amount of fluid passed to the reservoir, and thus the amount of fluid supplied to the elevator cylinder. The down valve unit has an inlet for connection to the elevator cylinder, a variable orifice connected to a reservoir, and a valve member for controllably varying the size of the orifice to control the rate of descent of the elevator.

Abstract: A position sensing system includes a coded tape vertically mounted in an elevator shaft and a sensor unit mounted on an elevator car to detect code indicia on the tape. The sensor unit is connected to output circuitry for converting the sensor outputs to elevator position data for transmission to an elevator controller. The tape has two parallel tracks of indicia extending along its length. The first track comprises a pseudo-random code sequence which is non-repeating along any N successive bits for the length of the tape, and the sensor unit includes a first set of sensors for detecting the indicia in the first track and producing an N-bit output representative of a coarse elevator position. The second track has spaced indicia forming a fine scale between successive coarse code positions on the first track, and a second set of sensors detects the fine code indicia and produces fine code position information at successive points between each pair of coarse code positions as the sensors traverse the tape.

Abstract: A system for reading or sensing the position of an elevator relative to a landing and for providing corresponding control signals to a controller for controlling the elevator movement in response to the sensed position comprises a tape veritically mounted in an elevator shaft and having reflective vanes positioned on it to indicate position relative to a landing. Sensors are mounted on the elevator car and produce predetermined output signals in response to detection of vanes, and suitable control circuitry responds to predetermined combinations of the sensor output signals to produce suitable output control signals to a controller which controls the car's speed, direction and positioning. The system is installed by first vertically mounting a suitable tape in an elevator shaft so that it runs through a sensor unit mounted on an elevator cab, and positioning vanes on the tape at predetermined positions relative to each floor.