HK1079171B - A passenger conveyor device assembly - Google Patents

Description

Passenger conveyor belt driving assembly

Technical Field

The present invention relates generally to escalator drive mechanisms, and more particularly to a fault detection and brake triggering device for an escalator drive mechanism.

Background

An escalator is a passenger conveyor that is commonly used to transport passengers between landings at different levels in a building, for example. The drive chain of the steps is typically driven by the use of a motor driven assembly. There are a variety of motorized drive assemblies that are proposed or currently in use. The introduction of new drive mechanisms necessitates new developments in control devices.

There are various situations when a brake should be activated to automatically stop or prevent further movement of an escalator step chain. For example, when the drive between the motor and the step chain fails, it is necessary to control the position of the escalator steps. For example, without the motive force of the motor, normal gravitational forces would cause undesirable movement of the escalator steps.

The present invention provides a sensor and brake triggering mechanism that can provide an indication and easily trigger a brake when a normal driving operation fails.

Disclosure of Invention

In general terms, the present invention is a sensor that provides an indication of whether the drive assembly of a passenger conveyor is operational and that can readily apply a braking force to resist further movement of the conveyor.

Specifically, the present invention provides a passenger conveyor drive assembly comprising: a motor; a driving member which moves in accordance with motive power from the motor; a driven member engaged with the drive member for movement in response to movement of the drive member, the movement of the driven member causing movement of the passenger conveyor; and a sensor member configured for movement with the driven member and to sense relative movement between the sensor member and the driven member.

An exemplary assembly designed according to this invention includes a motor and a drive member that moves in response to power from the motor. A driven member is engaged with the drive member for movement in response to movement of the drive member. When the driven member moves, it causes movement of the passenger conveyor. A sensor member moves relative to a selected portion of the drive assembly when the drive assembly fails. This movement of the sensor provides an indication that, for example, the brake should be applied.

In one example, the sensor member rotates in unison with the drive member under normal operating conditions. The sensor member engages the driven member and moves to provide an indication that braking is required based on the relative movement between the driving member and the driven member.

In one example, the drive member includes a drive wheel and a drive belt. The driven member includes a stopper chain having a plurality of links. During normal operation, the teeth on the drive belt engage corresponding teeth on the step chain. In the event of a failure of the transmission of drive from the drive assembly to the driven assembly, at least one of the step chain links will engage the sensor component. In this case, the sensor member is in one example a flange associated with the drive wheel that moves a selected distance relative to the drive wheel to indicate the need to stop the escalator.

In one example, movement of the sensor member relative to the drive member triggers a switch that provides a signal indicating that a problem with the normal condition is present in order to desire operation of the escalator drive assembly. The switch is used to activate a brake for stopping the escalator system.

In another example, the sensor member is biased to engage the drive belt. If the drive belt breaks, the sensor member will move because the belt is no longer in its intended position. This movement of the sensor member provides an indication that the brake should be applied.

The various advantages and features of this invention will become apparent to those skilled in the art from the following detailed description of the presently preferred configurations. The drawings that accompany the detailed description can be briefly described as follows.

Drawings

Figure 1 illustrates an escalator system designed according to this invention.

Figures 2A and 2B illustrate selected elements of an example escalator assembly including an example sensor designed according to this invention in greater detail.

FIG. 3 illustrates selected portions of the embodiment of FIG. 2A.

Fig. 4 shows in more detail the part enclosed in fig. 3 with the ring symbol 4.

Fig. 5 illustrates selected components of the step chain link used in the example of fig. 3.

FIG. 6 illustrates selected components of another exemplary sensor embodiment.

Figure 7 shows selected elements of another switch-activated embodiment in a first position.

Fig. 8 shows the element of fig. 7 in a second position.

Fig. 9 illustrates selected components of the exemplary sensor device of fig. 6 and 7.

Figure 10 illustrates another exemplary sensor designed according to this invention.

Figure 11 illustrates another exemplary sensor designed according to this invention.

Detailed Description

The escalator system 20 shown in fig. 1 includes a conventional escalator support structure 22 for supporting a plurality of steps 24 and handrails 26 for transporting passengers between floors within a building. A drive 30 operates under normal operating conditions to move the steps 24 in a selected direction at a desired speed.

Referring to fig. 2A and 2B, for example, the drive device 30 includes a motor assembly 32, which preferably includes a motor and a brake. The motor 32 provides a motive force to the drive wheel 34. The V-belt 35 is preferably driven by the motor 32 and the drive pulley 34. In this example, the belt has reinforcing cords surrounded by polyurethane. The internal teeth on the belt cooperate with the external teeth on the drive wheel 34.

The motive force on the belt 35 is preferably transferred to a plurality of step chain links 36 as the belt 35 is moved about an endless arrangement by the drive pulley 34 and the driven pulley 37. Under normal operating conditions, the belt 35 and the step chain links 36 move in unison based on the speed of movement of the drive pulley 34.

The engagement of the teeth on the drive belt 35 and the corresponding teeth 38 on the step chain links 36 provides the desired movement of the escalator steps at which point the step chain links 36 are coupled to the steps in a manner sufficient to cause such movement. Accordingly, the step chain links 36 preferably follow the entire path of movement of the steps as the drive belt 35 travels around a shorter loop.

A synchronizer bar 50 extends approximately the width of the steps so that the drive belt 35 and the series of step chain links 36, respectively, move synchronously with the edges of the steps to provide smooth, stable operation of the conveyor belt.

The device of the present invention includes a sensor that provides an indication of an undesirable condition of the drive device 30. In this example, the sensor includes a sensor member 40 coupled to the drive wheel 34. The sensor member 40 preferably includes a flange body portion 42 having a plurality of radially extending portions 44. In the example of fig. 2A, the sensor member 40 is generally star-shaped. The illustration of fig. 2B has the sensor component 40 removed.

Under normal operating conditions, the sensor member 40 rotates in unison with the drive wheel 34, which has no effect on the movement of the step chain. When a malfunction occurs during normal operating conditions of the drive, such as when the belt 35 breaks or breaks, there is relative movement between the drive pulley 34 and the step chain links 36. In such circumstances, a portion of at least one of the step chain links 36 engages at least one radially extending portion 44 on the sensor member 40 to cause the sensor member 40 to rotate relative to the drive pulley 34. This relative movement between the drive wheel 34 and the sensor member 40 triggers an indication that the drive device is malfunctioning relative to normal requirements.

An exemplary arrangement utilizing limited relative movement between the sensor member 40 and the drive wheel 34 is shown in fig. 3 and 4. In this example, the sensor member 40 generally rotates about the drive wheel 34. The synchronization device 60 maintains rotation of both under normal operating conditions.

The sensor member 40 is preferably first positioned relative to the drive wheel 34 such that a stop 62, which in this example is a bolt secured to the drive wheel 34, is positioned relative to a support surface 64 formed in a generally arcuate recess 66 in the sensor member 40. The support surface 64 preferably includes a partially rounded profile so that the bolt 62 rests on the surface 64. The bolt 62 is shown at one end 68 of the groove 66.

A spring 70 biases the sensor member 40 away from the drive wheel 34, generally in a direction parallel to the drive wheel axis of rotation. Initially, in the normal operating position, the spring 70 helps maintain the bolt 62 on the support surface 64. The contour of the surface 64 and the bias of the spring 70 are preferably arranged such that a minimum force required will cause the bolt 62 to move within the recess 66.

As can be seen in fig. 3 and 4, a plurality of synchronizing devices 60 are preferably spaced apart on the drive wheel 34 and the sensor member 40.

When there is relative motion between the step chain links 36 and the drive pulley 34, the engagement between the sensor member 40 and the step chain links 36 will cause relative motion between the drive pulley 34 and the sensor member 40. The bolt 62 will move away from the surface 64 and slide into one end 68 of the generally arcuate groove 66 depending on the direction of such relative movement. This movement of the bolt 62 within the recess 66 is a result of relative rotational movement between the drive wheel 34 and the sensor member 40.

In the example of fig. 3-5, the radial projections 44 on the sensor member 40 preferably mate with reference surfaces 72 formed on the step chain links 36. Under normal operating conditions, the radial projections 44 follow the datum surfaces 72 but do not engage them. When there is relative movement between the drive pulley 34 and the step chain links 36, the engagement between the reference surface 72 and the radial projections 44 will cause movement between the drive pulley 34 and the sensor member 40. In one example, the teeth 38 on the step chain links 36 are formed in a casting process and the datum surfaces 72 are machined separately. The present invention is not limited to this arrangement. It will be appreciated that various configurations for causing cooperative movement between the step chain links 36 and the sensor member 40 are within the scope of the present invention.

When the bolt 62 moves into one end 68 of the recess 66, the spring 70 causes relative movement of the sensor member 40 outwardly further away from the drive wheel 34. This movement will preferably trigger a switch 80. The switch 80 is preferably positioned relative to the sensor member 40 in such an instance that the switch is activated when there is relative movement between the step chain links 36 and the drive pulley 34. Activation of the switch 80 thus provides some indication of a failure of the drive connection between the drive pulley 34 and the step chain links 36.

In the exemplary embodiment, an electrical signal generated by switch 80 is received by a controller 82 that controls operation of motor and brake assembly 32. In one example, the controller 82 is an integral part of the motor assembly. The controller 82 preferably controls the operation of the motor assembly and the brake to ensure that the escalator steps 24 do not move in an undesirable manner after interruption of the normal operation of the drive assembly.

The controller 82 may be, for example, a conventional microprocessor suitably programmed to interpret signals from the switch 80 and control the motor and brake assembly 32 accordingly. In one example, the controller 82 is part of a controller that is already coupled with the escalator system. In another example, the controller 82 is a dedicated microprocessor system. Given this description, one of ordinary skill in the art will be able to select from among commercially available components and program a computer or controller to perform the functions necessary to achieve the results provided by the present invention.

Some failure of the drive assembly 30 (i.e., when the belt 35 breaks) will not allow the drive pulley 34 to apply any driving or braking force to the step chain links 36. For this case, some example embodiments of the present invention include a backup component that can operate independently of the functionality of the sensor described above. Referring again to fig. 2B, the drive wheel 34 includes a backup flange 100. For example, in contrast to fig. 2A or 3, the sensor component 40 in fig. 2B is removed to expose the back-up flange 100 that was hidden in fig. 2A and 3.

The back-up flange 100 in this example is preferably designed according to the teachings of published application WO02062694, which is commonly owned with the present application. The backup flange 100 in this example is fixed so as to remain stationary relative to the drive wheel 34. The backup flange 100 includes a plurality of teeth 102, the teeth 102 adapted to selectively engage the datum surfaces 72 on the step chain links 36 in the event of a failure of the engagement between the drive pulley 34, the drive belt 35, and the step chain links 36. In this situation, the teeth 102 transmit a driving or braking force to the step chain links 36 depending on the operation of the motor and brake assembly of the drive unit 30. In this example, the teeth 102 are not normally engaged with the reference surface 72 but only follow the reference surface as the drive pulley 34 and drive belt 35 rotate.

In one example, the teeth 102 of the backup flange 100 pull the radially extending portion 44 of the sensor 40 a small distance. In one example, a one millimeter difference is preferably provided between the teeth 102 on the backup flange 100 and the radially extending portion 44 on the sensor member 40. In this example, once the backup flange 100 is loaded due to relative movement between the drive pulley 34 and the step chain links 36, the protrusions 44 of the sensor member will align with the teeth 102 on the backup flange 100. When they move out of this alignment, the sensor component 40 triggers the switch 80 and the controller 82 takes appropriate action.

A backup flange, such as flange 100 of this example, is preferably included in the drive assembly regardless of the selected sensor embodiment. By using a sensor designed according to the present invention to separate backup and detection functions, it is possible to provide a necessary amount of force transfer while using a backup brake to avoid undesirable false shutdowns of the sensor device.

Another exemplary sensor 40' designed according to this invention is shown in fig. 6. The operation of this example is preferably similar to that shown in fig. 3 and 4, except for the engagement between the sensor flange portion 42 'and the step chain links 36'. In this example, the step chain links 36' preferably do not include a reference surface 72. Typically, the flange projections 44 'engage the teeth on the drive belt 35, but here the flange projections 44' directly engage the teeth 38 'on the step chain links 36' to provide an indication that the drive system is malfunctioning. Otherwise, the movement and support of the flange 42' is functionally identical to the flange 42 shown in fig. 3 and 4.

As can be appreciated from the example, the teeth 120 on the drive belt 35 pull the leading edge 122 of the radial projection 44 'so that the belt teeth 120 normally engage the teeth 38' on the step chain links 36 ', but the projection 44' does not. If the drive belt 35 breaks or wears such that the drive from the drive pulley 34 is no longer transmitted to the step chain, the projections 44 'will engage the step chain link teeth 38'. As the flange portion 42 'moves relative to the drive wheel 34, the sensor 40' provides the necessary indication of the condition sensed by the drive assembly in a manner similar to the flange 42 described above.

Another example sensor embodiment is shown in fig. 7 and 8. In this example, the sensor includes a pin 160 that engages the switch 80, rather than directly between the flange portion 44 of the sensor member 40 and the switch 80 in the previous example.

In this example, the drive wheel 34 preferably supports a pin 160 within a receiver portion 162, which may be, for example, a hole in the drive wheel. A biasing member 164, such as a spring, urges the pin 160 in a direction outward of the receiver portion 162. The exemplary pin 160 includes a base portion 166 and an extension arm 168.

Fig. 7 shows the pin 160 in a first position within the receiving portion 162. A solid portion 170 on the sensor member 40 maintains the pin 160 in a recessed position within the receiving portion 162. An opening 172 is provided on one side of the solid portion 170 and a second opening 174 is provided on the opposite side. When there is relative rotation between the sensor member 40 and the drive wheel 34, the pin arm 168 is biased outwardly from the receiving portion 162 and through a corresponding opening 172 or 174. This can be understood from, for example, fig. 8.

In the illustrative example, the pin 160 is allowed to slide within the groove of the drive wheel 34 after the pin extends through an opening in the sensor member 40. This arrangement is shown in fig. 9, in which a portion of the drive wheel 34 is shown. The receiver portion 162 extends a first depth into the drive wheel 34. An arcuate groove 190 corresponds to the receiver portion 162 but does not extend to a depth into the body of the drive wheel 34. Thus, when the pin is in the first position shown in fig. 7, it is retained within the receiver portion 162. When the pin 160 has extended through an opening in the sensor member 40, the base 166 is free to slide within the groove 190 so that there is a desired amount of relative rotation between the drive wheel 34 and the sensor member 40. The relative rotation of the pin 160 within the groove 190 prevents the pin from breaking or shearing as a result of forces associated with relative movement between the sensor member 40 and the drive wheel 34.

Figure 10 shows another example sensor device designed according to this invention. In this example, the sensor is particularly adapted to directly monitor the condition of the drive belts 35 and to correspondingly activate the brake device 32 when it is determined that at least one of the belts 35 is not operating as desired. In this example, the sensor 200 includes a roller 202 that is biased into engagement with the inside of the belt 35. In this example, a coil spring biasing member 204 urges roller 202 into engagement with the inner surface of belt 35. If the belt breaks, it will no longer move around the loop created by drive pulley 34 and driven pulley 37. Thus, the roller 202 will move outwardly (i.e., upwardly according to the illustration) and provide an indication that the roller is moving in that direction. Since the roller 202 moves in response to the absence of the belt 35, the switch 80 communicates to the controller 82 the need to trigger the brake mechanism 32 to apply a braking force. Given these descriptions, one of ordinary skill in the art will be able to select an appropriate switching element to implement such a braking application depending on the particular configuration and particular system design needs.

Fig. 11 shows another example of a belt sensor 210. In this example, the roller 212 is rotatably supported on a support member 214. The axis 215 extends from one side of the support 214 and is received in a through hole in a support bracket 216 that is secured to an appropriate portion of the structure to support the drive assembly 30. The support 214 and roller 212 are urged toward the belt 35 by a biasing member 218, which in this example comprises two coil springs.

Under normal operating conditions, the rollers 212 ride along the sides of the belt 35. Under certain conditions, it is desirable to monitor not only whether the belt is broken but also whether the teeth on the belt are fully engaged with the teeth on the step chain links. Wear or breakage of the belt teeth, for example, may occur even if the entire belt 35 is not broken. The examples of fig. 3-8 provide such monitoring capabilities.

The examples of fig. 9 and 10 show some possible sensor configurations to directly monitor the presence or condition of the belt 35. In some cases, it may be desirable to monitor not only whether the belt is broken, but also whether the teeth on the belt are adequately engaged with the teeth in the stepchain links. For example, it may occur that the belt teeth wear or break even though the entire belt 35 does not break. The examples of fig. 3-8 provide such monitoring possibilities.

The above example includes a switch activation where power is used to transmit a signal indicating that a brake should be applied. In some cases, a purely mechanical brake triggering mechanism may be required. For example, many encoders require a mechanical brake application mechanism for applying an auxiliary brake (i.e., applying an auxiliary brake to the brake associated with the motor and brake mechanism of the drive assembly). Any of the above-described exemplary sensor arrangements are effective with either an electric brake trigger or a purely mechanical brake trigger arrangement. The action of the sensor components of the various embodiments is effective to activate the switch. In some examples, the action of the sensor member may be used to apply a force to move a linkage of a mechanically triggered brake. For example, movement of the sensor member may pull a cable or a hard link member, which in turn moves an appropriate portion of a mechanical brake activation device.

The device of the present invention may be effective to activate a brake associated with the drive or to activate an auxiliary brake for preventing further undesirable movement of a passenger conveyor when normal force transmission between the drive assembly and the steps is interrupted due to a failure of one or more components of the drive.

The present invention provides a unique fault indicator and brake activation device for an escalator drive. The invention is particularly applicable to escalator drive arrangements which include a drive belt driven by a drive wheel, but is not limited to such arrangements.

The preceding description is exemplary rather than limiting in nature. It will be apparent to those skilled in the art that various changes and modifications can be made to the disclosed examples without departing from the spirit of the invention. The scope of legal protection given to this invention can only be determined by studying the following claims.

Claims (21)

1. A passenger conveyor belt drive assembly comprising:

a motor;

a driving member which moves in accordance with motive power from the motor;

a driven member engaged with the drive member for movement in response to movement of the drive member, the movement of the driven member causing movement of the passenger conveyor; and

a sensor member configured for movement with the driven member and to sense relative movement between the sensor member and the driven member.

2. The assembly of claim 1 including a brake that is activated in response to movement of the sensor member, the brake preventing further movement of the driven member.

3. An assembly according to claim 2, including a brake switch and a controller for controlling activation of the brake, wherein movement of the sensor member causes the switch to provide a signal to the controller.

4. The assembly of claim 1, wherein the drive member includes a drive guide roller that rotates in response to force from the motor, and wherein the sensor member includes a flange that rotates with the drive guide roller, and wherein the sensor movement includes rotation relative to the flange of the drive guide roller in response to relative movement between the drive member and the driven member.

5. The assembly of claim 4 wherein the drive member comprises a drive belt moving with the drive guide roller and the driven member comprises a chain, the sensor member having a plurality of radial projections which engage corresponding portions of the chain of the driven member during relative movement between the drive member and the driven member.

6. An assembly as claimed in claim 5 wherein the chain of driven members comprises a plurality of links, each link having a first set of teeth engaging a corresponding surface on the drive belt and a plurality of datum surfaces engaging the radial projections during the relative movement.

7. The assembly of claim 4 including a stop member movable with the drive roller, the sensor member including a recess through which at least a portion of the stop member is received, the stop member being movable within the recess in response to relative movement between the drive member and the driven member from a first position in which the sensor member and the drive member move synchronously to a second position.

8. The assembly of claim 7 including a biasing member biasing the sensor member away from the drive roller, the biasing member causing relative movement between the drive roller and the sensor member in a direction corresponding to movement of the stop member in the groove to the second position.

9. The assembly of claim 4, including a pin coupled to the drive member and biased to a trigger position, wherein the sensor member retains the pin from the trigger position when the sensor member moves with the drive member but releases the pin for movement to the start position in response to relative movement between the drive member and the sensor member.

10. The assembly of claim 1, wherein the drive member comprises a belt and the sensor member is biased into engagement with the belt, the sensor member moving in response to the bias when the belt condition changes.

11. The assembly of claim 10 wherein the sensor member comprises a roller biased against a side of the belt, the roller rotating about an axis in response to movement of the belt and moving laterally relative to the axis in response to a change in the condition of the belt, the lateral movement providing an indication of the change in the condition of the belt.

12. The assembly of claim 10 wherein the sensor member comprises a roller biased against an inner surface of the belt, the roller rotating about an axis in response to movement of the belt and moving laterally relative to the axis in response to a change in a condition of the belt, the lateral movement providing an indication of the change in the condition of the belt.

13. The assembly of claim 1, wherein the drive member includes a pulley driven by the motor, the driven member including a step chain having a plurality of links engaged by the engagement member to move the step chain in response to movement of the drive member, wherein the sensor member rotates in unison with the pulley member, the sensor member engaging a mating portion of the step chain and moving relative to the pulley member in response to relative movement between the step chain and the pulley member.

14. The assembly of claim 13 wherein the drive member comprises a belt movable in response to movement of the pulley member, the belt having a plurality of teeth for engaging corresponding teeth on the step chain links.

15. The assembly of claim 13 including a brake associated with the motor, wherein the brake is activated in response to relative movement between the pulley member and the sensor member.

16. The assembly of claim 13 including a biasing member biasing the sensor member away from the pulley member in a direction parallel to the axis of rotation of the pulley member, the biasing member operating to move the sensor member away from the pulley member to provide an indication of relative movement between the pulley member and the sensor member.

17. The assembly of claim 13, wherein the step chain links include datum surfaces and the sensor component includes a flange having radial projections, wherein the radial projections engage the datum surfaces in response to relative movement between the step chain and the pulley.

18. The assembly of claim 1, wherein the drive member includes a pulley member driven by the motor and a belt moving in response to movement of the pulley member, the driven member including a step chain having a plurality of links engaged by the belt to move the step chain in response to movement of the drive member; the sensor member is biased towards and into engagement with the belt, the sensor member moving out of the engaged position in response to a change in the condition of the belt, movement of the sensor member beyond the engaged position providing an indication of a change in the condition of the belt.

19. The assembly of claim 18 wherein the sensor member comprises a roller laterally biased against the belt, the roller rotating about an axis in response to movement of the belt and moving laterally relative to the axis in response to a change in the condition of the belt, the lateral movement providing an indication of the change in the condition of the belt.

20. The assembly of claim 18 wherein the sensor member comprises a roller biased against an inner surface of the belt, the roller rotating about an axis in response to movement of the belt and moving laterally relative to the axis in response to a change in the condition of the belt, the lateral movement providing an indication of the change in the condition of the belt.

21. The assembly of claim 1 wherein the sensor member moves in response to relative movement between the driving member and the driven member.