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US-12623885-B2 - Elevator position measurement system

US12623885B2US 12623885 B2US12623885 B2US 12623885B2US-12623885-B2

Abstract

An elevator system includes an elevator car, an elongate tension member operably connected to the elevator car and configured to move the elevator car, and an elevator car position measurement system. The elevator car position measurement system includes a pulse generator configured to transmit a pulse along the elongate tension member; and a detector unit configured to receive the pulse from the pulse generator after the pulse has been transmitted along a length of the elongate tension member and to record a time at which the pulse is received. One of the pulse generator and the detector unit is arranged to move within the hoistway dependent on a position of the elevator car within the hoistway, such that a length of the elongate tension member along which the pulse is transmitted changes dependent on a position of the elevator car within the hoistway.

Inventors

  • Ergün Alkan

Assignees

  • OTIS ELEVATOR COMPANY

Dates

Publication Date
20260512
Application Date
20221027
Priority Date
20220302

Claims (14)

  1. 1 . An elevator system ( 200 , 400 ) comprising an elevator car ( 220 ), an elongate tension member ( 226 ) operably connected to the elevator car ( 220 ) and configured to move the elevator car ( 220 ) within a hoistway ( 240 ), and an elevator car position measurement system ( 300 , 500 ) comprising: a pulse generator ( 202 ) configured to transmit a pulse ( 334 ) along the elongate tension member ( 226 ) from a first location on the elongate tension member ( 226 ) towards a second location on the elongate tension member ( 226 ); a detector unit ( 218 ) configured to receive the pulse ( 334 ) from the pulse generator ( 202 ) after the pulse ( 334 ) has been transmitted along a length of the elongate tension member ( 226 ) and to record a time at which the pulse ( 334 ) is received; wherein (i) the pulse generator ( 202 ) is arranged to move within the hoistway ( 240 ) dependent on a position of the elevator car ( 220 ) within the hoistway ( 240 ) or (ii) the detector unit ( 218 ) is arranged to move within the hoistway ( 240 ) dependent on the position of the elevator car ( 220 ) within the hoistway ( 240 ), wherein the length of the elongate tension member ( 226 ) between the pulse generator ( 202 ) and the detector unit ( 218 ) along which the pulse ( 334 ) is transmitted changes dependent on the position of the elevator car ( 220 ) within the hoistway ( 240 ), and wherein the elevator car position measurement system ( 300 , 500 ) is configured to determine the length of the elongate tension member ( 226 ) along which the pulse ( 334 ) is transmitted based on the recorded time, and determine the position of the elevator car ( 220 ) within the hoistway ( 240 ) based on the determined length.
  2. 2 . The elevator system ( 200 , 400 ) according to claim 1 , wherein the detector unit ( 218 ) is positioned at a first end ( 208 ) of the elongate tension member ( 226 ).
  3. 3 . The elevator system ( 200 , 400 ) according to claim 1 , wherein the pulse generator ( 202 ) is configured to transmit the pulse ( 334 ) along the elongate tension member ( 226 ) in a direction towards the detector unit ( 218 ).
  4. 4 . The elevator system ( 200 , 400 ) according to claim 1 , wherein the pulse generator ( 202 ) is mounted on the elevator car ( 220 ) and the detector unit ( 218 ) is mounted at a fixed position relative to the elongate tension member ( 226 ).
  5. 5 . The elevator system ( 200 , 400 ) according to claim 1 , wherein the pulse generator ( 202 ) is mounted in a fixed position in the hoistway ( 240 ) and the detector unit ( 218 ) is mounted on the elevator car ( 220 ).
  6. 6 . The elevator system ( 200 , 400 ) according to claim 1 , wherein the elevator car position measurement system ( 300 , 500 ) further comprises an initial pulse generator ( 328 ) configured to send an initial pulse ( 332 ) along the elongate tension member ( 226 ) towards the pulse generator ( 202 ) to thereby induce a current in the pulse generator ( 202 ).
  7. 7 . The elevator system ( 200 , 400 ) according to claim 6 , wherein the pulse generator ( 202 ) is configured to transmit the pulse ( 334 ) along the elongate tension member ( 226 ) in a direction towards the detector unit ( 218 ) in response to the induced current.
  8. 8 . The elevator system ( 200 , 400 ) according to claim 6 , wherein the elevator car position measurement system ( 300 , 500 ) further comprises a terminating connector ( 334 ) coupled to the elongate tension member ( 226 ) and configured to prevent reflection of the initial pulse ( 332 ) back towards the initial pulse generator ( 328 ).
  9. 9 . The elevator system ( 200 , 400 ) according to claim 1 , wherein the detector unit ( 218 ) is configured to record a pulse start time, wherein the pulse start time is a time at which the pulse generator ( 202 ) transmits the pulse ( 334 ) along the elongate tension member ( 226 ) or a time at which the initial pulse generator ( 328 ) sends the initial pulse ( 332 ) towards the pulse generator ( 202 ).
  10. 10 . The elevator system ( 200 , 400 ) according to claim 9 , wherein the detector unit ( 218 ) further comprises a measurement system control unit ( 336 ) configured to determine a time interval between the pulse start time and the time at which the pulse ( 334 ) is received by the detector unit ( 218 ).
  11. 11 . The elevator system ( 200 , 400 ) according to claim 10 , wherein the measurement system control unit ( 336 ) is configured to calculate, from the determined time interval, position information indicating the position of the elevator car ( 220 ) within the hoistway ( 240 ).
  12. 12 . The elevator system ( 200 , 400 ) according to claim 11 , further comprising an elevator control unit ( 604 ), wherein the measurement system control unit ( 336 ) is configured to transmit the position information to the elevator control unit ( 604 ).
  13. 13 . The elevator system ( 200 , 400 ) according to claim 1 , wherein the elongate tension member ( 226 ) comprises a plurality of tension cords ( 338 a , 338 b ) surrounded by a sheath ( 342 ), and wherein the pulse generator ( 202 ) is configured to send the pulse ( 334 ) along one of the plurality of tension cords ( 338 a , 338 b ).
  14. 14 . An elevator car position measurement system ( 300 , 500 ) for an elevator system ( 200 , 400 ) comprising an elongate tension member ( 226 ) operably connected to an elevator car ( 220 ) and configured to move the elevator car ( 220 ) within the hoistway ( 240 ), the elevator car position measurement system ( 300 , 500 ) comprising: a pulse generator ( 202 ) configured for transmitting a pulse ( 334 ) along the elongate tension member ( 226 ) from a first location on the elongate tension member ( 226 ) towards a second location on the elongate tension member ( 226 ); a detector unit ( 218 ) configured to receive the pulse ( 334 ) from the pulse generator ( 202 ) after the pulse ( 334 ) has been transmitted along a length of the elongate tension member ( 226 ) and to record a time at which the pulse ( 334 ) is received; wherein (i) the pulse generator ( 202 ) is arranged to move within the hoistway ( 240 ) dependent on a position of the elevator car ( 220 ) within the hoistway ( 240 ) or (ii) the detector unit ( 218 ) is arranged to move within the hoistway ( 240 ) dependent on the position of the elevator car ( 220 ) within the hoistway ( 240 ), wherein the length of the elongate tension member ( 226 ) between the pulse generator ( 202 ) and the detector unit ( 218 ) along which the pulse ( 334 ) is transmitted changes dependent on the position of the elevator car ( 220 ) within the hoistway ( 240 ), and wherein the elevator car position measurement system ( 300 , 500 ) is configured to calculate the length of the elongate tension member ( 226 ) along which the pulse ( 334 ) is transmitted based on the recorded time, and determine the position of the elevator car ( 220 ) within the hoistway ( 240 ) based on the determined length.

Description

FOREIGN PRIORITY This application claims priority to European Patent Application No. 22159813.9, filed Mar. 2, 2022, and all the benefits accruing therefrom under 35 U.S.C. § 119, the contents of which in its entirety are herein incorporated by reference. TECHNICAL FIELD This disclosure relates to an elevator position measurement system, which determines the position of an elevator car within an elevator hoistway and a method of measuring a position of an elevator car within a hoistway of an elevator system. BACKGROUND It is known to provide an elevator hoistway with a length of tape, arranged to extend vertically in the hoistway, and fixedly fastened to the hoistway wall. The elevator car includes a sensor e.g. a camera, able to sense certain features e.g. incremental markings, along the length of the tape, and the sensed features are used to determine the position of the elevator car within the hoistway. This prior art arrangement is described in greater detail below with reference to FIG. 1. Certain drawbacks with such known position measurement tape arrangements have been appreciated and the elevator position measurement system according to the present disclosure seeks to address these shortcomings. SUMMARY According to a first aspect of this disclosure there is provided an elevator system comprising an elevator car, an elongate tension member operably connected to the elevator car and configured to move the elevator car within a hoistway, and an elevator car position measurement system comprising: a pulse generator configured to transmit a pulse along the elongate tension member; a detector unit configured to receive the pulse from the pulse generator after the pulse has been transmitted along a length of the elongate tension member and to record a time at which the pulse is received; wherein one of the pulse generator and the detector unit is arranged to move within the hoistway dependent on a position of the elevator car within the hoistway, such that a length of the elongate tension member along which the pulse is transmitted changes dependent on a position of the elevator car within the hoistway, and wherein the elevator car position measurement system is configured to determine the length of the elongate tension member along which the pulse is transmitted based on the recorded time, and determine the position of the elevator car within the hoistway based on the determined length. Optionally, the detector unit is positioned at a first end of the elongate tension member. Optionally, the pulse generator is configured to transmit the pulse along the elongate tension member in a direction towards the detector unit. Optionally, the pulse generator is mounted on the elevator car and the detector unit is mounted at a fixed position relative to the elongate tension member. Optionally, the pulse generator is mounted in a fixed position in the hoistway and the detector unit is mounted on the elevator car. Optionally, the elevator car position measurement system further comprises an initial pulse generator configured to send an initial pulse along the elongate tension member towards the pulse generator to thereby induce a current in the pulse generator. Optionally, the pulse generator is configured to transmit the pulse along the elongate tension member in a direction towards the detector unit in response to the induced current. Optionally, the elevator car position measurement system further comprises a terminating connector coupled to the elongate tension member and configured to prevent reflection of the initial pulse back towards the initial pulse generator. Optionally, the detector unit is configured to record a pulse start time, wherein the pulse start time is a time at which the pulse generator transmits the pulse along the elongate tension member or a time at which the initial pulse generator sends the initial pulse towards the pulse generator. Optionally, the detector unit further comprises a measurement system control unit configured to determine a time interval between the pulse start time and the time at which the pulse is received by the detector unit. Optionally, the measurement system control unit is configured to calculate, from the determined time interval, position information indicating the position of the elevator car within the hoistway. Optionally, the elevator system further comprises an elevator control unit, wherein the measurement system control unit is configured to transmit the position information to the elevator control unit. Optionally, the elongate tension member comprises a plurality of tension cords surrounded by a sheath, and the pulse generator is configured to send the pulse along one of the plurality of tension cords. According to a second aspect of this disclosure there is provided an elevator car position measurement system for an elevator system comprising an elongate tension member operably connected to an elevator car and configured to move the elevator car within th