Abstract: A system of sensing elevator car position is presented that dynamically compensates for problems due to frictional slippage of its mechanical connection and/or building settlement. The system comprises an elevator car within an elevator hoistway. An encoder is mounted within the elevator hoistway and mechanically connected to the elevator car. The mechanical connection drives the encoder which generates data indicative of the position of the elevator car. Either one of a position sensor and a position sensor actuator is mounted to a landing of the hoistway. The other one of the position sensor and position sensor actuator is mounted to the elevator car. The position sensor generates data indicative of the elevator car floor reaching a predetermined distance from the elevator landing when actuated by the position sensor actuator. An elevator position controller receives the data generated by both the position sensor and the encoder.

Abstract: A system of sensing elevator car position is presented that dynamically compensates for problems due to frictional slippage of its mechanical connection and/or building settlement. The system comprises an elevator car within an elevator hoistway. An encoder is mounted within the elevator hoistway and mechanically connected to the elevator car. The mechanical connection drives the encoder which generates data indicative of the position of the elevator car. Either one of a position sensor and a position sensor actuator is mounted to a landing of the hoistway. The other one of the position sensor and position sensor actuator is mounted to the elevator car. The position sensor generates data indicative of the elevator car floor reaching a predetermined distance from the elevator landing when actuated by the position sensor actuator. An elevator position controller receives the data generated by both the position sensor and the encoder.

Abstract: A system of sensing elevator car position is presented that dynamically compensates for problems due to frictional slippage of its mechanical connection and/or building settlement. The system comprises an elevator car within an elevator hoistway. An encoder is mounted within the elevator hoistway and mechanically connected to the elevator car. The mechanical connection drives the encoder which generates data indicative of the position of the elevator car. Either one of a position sensor and a position sensor actuator is mounted to a landing of the hoistway. The other one of the position sensor and position sensor actuator is mounted to the elevator car. The position sensor generates data indicative of the elevator car floor reaching a predetermined distance from the elevator landing when actuated by the position sensor actuator. An elevator position controller receives the data generated by both the position sensor and the encoder.

Abstract: Retroreflective tape 28, 29 disposed on select positions on an elevator guide rail 13 is sensed by infrared transceivers 24, 25 disposed on an elevator car 10 to provide a signal indicative of the elevator as being at a vertical position in a hoistway designated by said retroreflective tape.

Abstract: A telephone transmit circuit is connected through a resistor to a junction at which a telephone line interface circuit is connected, a transhybrid cancellation circuit is connected to the transmit circuit and includes a high frequency shunt matching network having capacitive and inductive components and a low frequency matching circuit which comprises a lead lag network having capacitive components, the output of the transhybrid circuit being connected to a summing junction at the input of a telephone receiver. The other input of the summing network is connected between the resistor and the interface circuit, whereby a portion of the transmit signal is fed back out of phase to the receive amplifier so as to cancel out undesirable side tones, across a predetermined frequency range.

Abstract: In an elevator system, primary marking means, placed near every floors and secondary marking means placed near alternate floors are read by a scanner. Upon scanning, a marking number signal is provided indicating whether a primary marking means and secondary marking means, or only a primary marking means, is read at a floor level. As the car moves in the hoistway, current position, direction of the elevator car, and the marking number signal is continuously updated and stored in non-volatile memory. Upon recovery from a loss of power, the car is moved to the next floor in the direction it was moving prior to loss of power. By comparing the marking number signal stored in non-volatile memory before power was lost with the marking number signal generated after regaining power, the stored position can be confirmed to be correct or, if incorrect, incremented or decremented by one floor, depending upon whether the car was moving up or down respectively, to identify the actual car position.

Abstract: A serial signal communications system includes a central station unit connected through a balanced impedance signal communication bus to one or more remote station units.