EP1678060B1 - Passenger conveyor drive monitoring arrangement with brake actuation - Google Patents

Passenger conveyor drive monitoring arrangement with brake actuation Download PDF

Info

Publication number
EP1678060B1
EP1678060B1 EP03779401A EP03779401A EP1678060B1 EP 1678060 B1 EP1678060 B1 EP 1678060B1 EP 03779401 A EP03779401 A EP 03779401A EP 03779401 A EP03779401 A EP 03779401A EP 1678060 B1 EP1678060 B1 EP 1678060B1
Authority
EP
European Patent Office
Prior art keywords
wheels
drive
assembly
wheel
rotating
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP03779401A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP1678060A1 (en
EP1678060A4 (en
Inventor
Markus Hame
Andreas Stuffel
Thorsten Robke
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Otis Elevator Co
Original Assignee
Otis Elevator Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Otis Elevator Co filed Critical Otis Elevator Co
Publication of EP1678060A1 publication Critical patent/EP1678060A1/en
Publication of EP1678060A4 publication Critical patent/EP1678060A4/en
Application granted granted Critical
Publication of EP1678060B1 publication Critical patent/EP1678060B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B29/00—Safety devices of escalators or moving walkways
    • B66B29/005—Applications of security monitors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B23/00—Component parts of escalators or moving walkways
    • B66B23/02—Driving gear
    • B66B23/028—Driving gear with separate drive chain or belt that engages directly the carrying surface chain
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B25/00—Control of escalators or moving walkways
    • B66B25/006—Monitoring for maintenance or repair

Definitions

  • This invention generally relates to passenger conveyor drive systems. More particularly, this invention relates to an arrangement for monitoring the operative condition of a passenger conveyor drive system and for actuating a brake as may be needed.
  • Escalator systems typically include a chain of steps that moves along a loop to carry passengers between landings in different levels of a building, for example.
  • Most escalator systems include at least one drive machine that propels the steps in the desired direction.
  • a drive sprocket engages a step chain, which is associated with the steps to cause the desired step movement.
  • Other passenger conveyors have similar or identical arrangements although the steps may move passengers horizontally.
  • This invention addresses the need for monitoring the condition of a drive assembly and actuating a brake as may be needed in a passenger conveyor drive arrangement that includes a drive member for moving the step chain.
  • this invention is a drive assembly monitoring technique that utilizes relative speeds of sheaves or sprockets as an indication of the condition of the drive assembly.
  • One example drive assembly includes a plurality of drive wheels.
  • a drive member such as a belt is associated with each drive wheel.
  • Each drive member follows a path around the associated drive wheel and at least one deflection wheel.
  • a monitor device is associated with selected wheels to provide an indication of relative rotation between the selected wheels.
  • the monitor device when there is a difference in the speed of rotation of the selected wheels, the monitor device provides an indication of such relative rotation and facilitates actuating a brake to prevent the steps from moving.
  • the relative rotation between the sheaves indicates a broken drive member.
  • One example monitor device includes a first rotating member that is coupled to rotate with the first one of the selected wheels.
  • a second rotating member is coupled to rotate with a second one of the selected wheels.
  • the first and second rotating members begin in a first axial position and remain in that position while the selected wheels rotate at the same speed.
  • At least one of the rotating members moves to a second position responsive to relative rotation between the selected wheels.
  • the rotating member moves axially relative to the other rotating member when there is a speed difference between the sheaves and, therefore, the rotating members.
  • That movement in one example operates an actuator that, in turn, actuates a brake associated with the escalator system.
  • Figure 1 schematically shows an escalator system 20 having a plurality of steps 22 that move between landings 24 and 26 in a generally known manner.
  • the steps 22 follow a track (not illustrated) that is supported as part of an escalator truss structure 28.
  • a step chain 30 includes a plurality of links 32 that are associated with the steps 22 so that movement of the step chain 30 causes movement of the steps 22.
  • a drive assembly 40 includes a drive member 42 that interacts with the links 32 of the step chain 30 to cause the desired movement of the steps 22.
  • the drive member 42 in one example is a polyurethane belt having reinforcing members such as steel cords.
  • the drive member 42 comprises a chain.
  • the drive member 42 will be referred to as a belt.
  • the belt 42 preferably is toothed and follows a path defined by a drive wheel 44 and a deflection wheel 46.
  • a machine (i.e., motor and brake) 48 causes movement of the drive wheel 44, which propels the belt 42 around the path and, in turn, propels the step chain 30 and steps 22 in the desired manner.
  • the wheels 44, 46 comprise sprockets.
  • the wheels comprise grooved sheaves.
  • FIG 2 schematically illustrates an example drive assembly 40 having two drive members 42. Each drive member 42 is associated with a step chain 30 on the opposite lateral sides of the steps 22.
  • a machine 48 is associated with each of the drive wheels 44 and the corresponding belts 42.
  • Figure 2 schematically shows a monitor device 50 that monitors an operating condition of the drive assembly 40.
  • the monitor device 50 is capable of providing information regarding a condition of the belts 42, such as when one or both of the belts 42 breaks.
  • the monitor device 50 includes a first rotating member 52 that rotates with a shaft 54, which rotates with the deflection wheel 46.
  • a second rotating member 56 rotates in unison with a shaft 58, which rotates with the other deflection wheel 46.
  • At least one of the rotating members 52, 56 is associated with a brake actuator 60 that operates to actuate a brake 62:
  • the actuator 60 and brake 62 are schematically shown and comprise known components.
  • the brake 62 may be part of the machine brake or an auxiliary, emergency stopping brake, depending on the needs of a particular situation.
  • the actuator 60 may be electric, cable-based or some combination of these. Those skilled in the art who have the benefit of this description will be able to arrange braking components as needed to meet the needs of their particular situation.
  • the first rotating member 52 of the example monitoring device 50 is a bushing that rotates with the shaft 54, in unison with rotation of the deflection wheel 46.
  • An engaging surface 64 on the bushing 52 cooperates with a corresponding engaging surface 66 on the second rotating member 56, which also is a bushing in this example.
  • the first rotating member 52 is biased toward the second rotating member 56 such that the engaging surfaces 64 and 66 are aligned as shown in Figure 3 .
  • the engaging surfaces 64 and 66 are at least partially arranged at an oblique angle relative to the axis of rotation of the rotating members 52 and 56.
  • a spring 68 biases the first rotating member 52 toward the second rotating member 56.
  • a plate 70 is secured to rotate with the first rotating member 52.
  • the plate 70 causes a follower 72 to move axially as part of the plate 70 is received within a groove 74 on the follower 72.
  • One end 76 of the follower 72 is received to slide within a channel 78 formed on a support 80 as shown.
  • the support 80 is secured to a selected portion of a drive assembly support structure 82 ( Figure 2 ), which is associated with the escalator truss 28 in a generally known manner.
  • the axial movement of the follower 72 can be appreciated by comparing the position of the follower 72 with the setting member 84 in Figure 3 and Figure 4 . As the follower 72 moves away from the setting member 84, that provides an indication of a malfunction, such as a broken belt condition.
  • the monitoring device 50 provides an indication of a malfunction in the drive assembly, which normally has both belts 42 and all four sheaves 44, 46 rotating at the same speed. In the event that there is any relative rotation between them (i.e., a speed difference between at least two selected wheels), that is an indication of a malfunction in the drive assembly, which may be used to actuate a brake, if desired.
  • the example embodiment of Figure 2 is useful for indicating when one of the belts 42 becomes broken or damaged, for example.
  • the embodiment of Figure 5 is useful for indicating a situation where either belt 42 is damaged or both of the belts 42 are simultaneously broken or damaged. The latter condition may not be fully appreciable using an embodiment as schematically shown in Figure 2 .
  • the modified rotating member 56' includes a follower portion 90 that is associated with a connector 92, which causes the follower portion 90 to rotate at the same speed as a pulley 94 associated with a synchronizer bar 96 that rotates in unison with the drive wheels 44.
  • the follower portion 90 comprises a groove on the second rotating member 56.
  • the follower portion 90 comprises a separate sheave that is arranged to rotate in unison with at least one of the rotating members 52, 56'.
  • a single second rotating member 56' is associated with two first rotating members 52A and 52B.
  • Each of the first rotating members 52A, 52B are associated with a respective one of the deflection wheels 46 to rotate in unison with the associated sheave.
  • the second rotating member 56' will rotate relative to the corresponding first rotating member 52 (A or B) causing at least one of the rotating members to move axially as described above. This results in operating the actuator mechanism 60, which in turn may operate a brake as needed.
  • Figure 5 allows for separately monitoring each belt 42 or both belts 42 using a single monitoring device arrangement. If both belts 42 broke simultaneously, there would still be relative rotation between the members 56' and 52A, B.
  • Another example embodiment includes dedicated first rotating members 52 and second rotating members 56 associated with each deflection wheel 46 and a synchronizing arrangement to cause the rotating members to rotate in unison and at the same speed as the drive wheels 44 under normal operating conditions.

Landscapes

  • Escalators And Moving Walkways (AREA)
  • Braking Arrangements (AREA)
EP03779401A 2003-10-29 2003-10-29 Passenger conveyor drive monitoring arrangement with brake actuation Expired - Lifetime EP1678060B1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US2003/034258 WO2005051811A1 (en) 2003-10-29 2003-10-29 Passenger conveyor drive monitoring arrangement with brake actuation

Publications (3)

Publication Number Publication Date
EP1678060A1 EP1678060A1 (en) 2006-07-12
EP1678060A4 EP1678060A4 (en) 2009-07-22
EP1678060B1 true EP1678060B1 (en) 2011-05-04

Family

ID=34632373

Family Applications (1)

Application Number Title Priority Date Filing Date
EP03779401A Expired - Lifetime EP1678060B1 (en) 2003-10-29 2003-10-29 Passenger conveyor drive monitoring arrangement with brake actuation

Country Status (8)

Country Link
EP (1) EP1678060B1 (ja)
JP (1) JP4783148B2 (ja)
CN (1) CN1860074B (ja)
AT (1) ATE508079T1 (ja)
AU (1) AU2003285085A1 (ja)
DE (1) DE60337037D1 (ja)
HK (1) HK1098443A1 (ja)
WO (1) WO2005051811A1 (ja)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ATE456030T1 (de) 2006-04-25 2010-02-15 Busch Dieter & Co Prueftech Verfahren zum überwachen der torsionsfestigkeit einer welle
CN101264843B (zh) * 2008-03-05 2010-06-02 上海中业电梯有限公司 自动扶梯运行安全监控方法及装置
US11230459B2 (en) 2020-06-26 2022-01-25 Otis Elevator Company Belt-driven escalator
EP3929138A1 (en) * 2020-06-26 2021-12-29 Otis Elevator Company Belt-driven escalator

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1610428A (en) * 1922-08-30 1926-12-14 Otis Elevator Co Safety device for escalators
JPS45757Y1 (ja) * 1966-03-16 1970-01-13
JPS5823823Y2 (ja) * 1978-10-31 1983-05-21 三菱電機株式会社 乗客コンベヤ装置
GB8602846D0 (en) * 1986-02-05 1986-03-12 Fletcher Sutcliffe Wild Ltd Belt conveyor drive system
MY106142A (en) * 1990-02-20 1995-03-31 Toshiba Kk Man conveyor.
US5076568A (en) * 1990-07-26 1991-12-31 Xerox Corporation Damping servo-motor control
JPH04191289A (ja) * 1990-11-27 1992-07-09 Hitachi Building Syst Eng & Service Co Ltd 乗客コンベアの監視装置
JP3061484B2 (ja) * 1992-09-07 2000-07-10 株式会社東芝 マンコンベアの制御装置
CN2229917Y (zh) * 1993-09-16 1996-06-26 苏州迅达电梯有限公司 自动扶梯运行及故障监控装置
CN1086673C (zh) * 1996-09-03 2002-06-26 奥蒂斯电梯公司 一种乘客输送机
CN2375603Y (zh) * 1999-06-11 2000-04-26 承德特种输送机实业有限公司 输送线双机驱动电气控制装置

Also Published As

Publication number Publication date
WO2005051811A1 (en) 2005-06-09
ATE508079T1 (de) 2011-05-15
HK1098443A1 (en) 2007-07-20
CN1860074B (zh) 2010-06-02
EP1678060A1 (en) 2006-07-12
JP4783148B2 (ja) 2011-09-28
DE60337037D1 (de) 2011-06-16
JP2007521207A (ja) 2007-08-02
EP1678060A4 (en) 2009-07-22
AU2003285085A1 (en) 2005-06-17
CN1860074A (zh) 2006-11-08

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