System for detecting broken comb plate teeth of escalator

Abstract

The invention relates to a system for detecting broken comb plate teeth of an escalator. An escalator system is provided and includes: a comb plate including teeth; a moving step, the moving step comprising grooves and being drivable to pass through the comb plate at a step-comb plate interface at which each tooth passes through a corresponding groove when each tooth is properly positioned, and a moving step, the moving step comprising grooves and being drivable to pass through the comb plate at a step-comb plate interface at which each tooth passes through a corresponding groove when each tooth is properly positioned; and a detection system. The detection system includes a pair of transmitters and receivers and is configured to determine whether a signal pattern derived from communications of the pair of transmitters and receivers and partially reflecting a condition of the tooth indicates that at least one tooth is incorrectly positioned.

Description

Technical Field

[0001] The present disclosure relates to escalator systems, and in particular to systems and methods for detecting broken combplate teeth of an escalator. Background Art

[0002] People conveying devices such as escalators and moving walkways typically include a conveyor belt that moves with people standing thereon between opposing landing zones, and a drive machine that drives the movement of the conveyor belt and comb plates. The conveyor belt extends and moves between opposing landing zones and has a surface that typically includes cleats and grooves. Comb plates are provided at the opposing landing zones. Each comb plate includes teeth that extend into grooves in the surface of the conveyor belt as the conveyor belt moves relative to each comb plate, and a cleat moves along each of the teeth. Broken teeth of a comb plate can degrade the performance of the comb plate and the escalator as a whole.

[0003] Therefore, a need exists for a system and method that provides traffic monitoring and pinch detection for a comb plate to allow pinch events to be reliably detected. Summary of the invention

[0004] According to the disclosed aspects, an escalator system is provided and includes: a comb plate including teeth; a moving step including grooves and being drivable to pass through the comb plate at a step-comb plate interface, where each tooth passes through a corresponding groove when each tooth is correctly positioned; and a detection system. The detection system includes a transmitter and a receiver pair and is configured to determine whether a signal pattern derived from communication between the transmitter and the receiver pair and partially reflecting a condition of the teeth indicates that at least one tooth is incorrectly positioned.

[0005] According to an additional or alternative embodiment, the signal mode is a sound mode.

[0006] According to additional or alternative embodiments, the transmitter and receiver pair includes a transmitter and receiver arranged proximate to a plane of the step-comb interface.

[0007] According to additional or alternative embodiments, the transmitter and receiver pair comprises an ultrasound transmitter.

[0008] According to an additional or alternative embodiment, the transmitter and receiver pair comprises a transmitter and a receiver respectively connected to the outermost teeth of the comb plate.

[0009] According to additional or alternative embodiments, at least one of the frequency, amplitude and shape of the signal pattern indicates that at least one tooth is incorrectly positioned.

[0010] According to additional or alternative embodiments, the detection system is further configured to determine whether the signal pattern is one of: indicating that at least one tooth is incorrectly positioned such that the comb plate requires attention and no escalator stop is warranted; and indicating that at least one tooth is incorrectly positioned such that an escalator stop is warranted.

[0011] According to additional or alternative embodiments, the detection system is further configured to perform an escalator stop.

[0012] According to aspects of the present disclosure, an escalator system is provided and includes: a comb plate including teeth; a moving step including grooves and being drivable to pass through the comb plate at a step-comb plate interface, where each tooth passes through a corresponding groove when each tooth is correctly positioned; and a detection system. The detection system includes a transmitter and a receiver pair, and is configured to determine whether a signal pattern derived from communication between the transmitter and the receiver pair and partially reflecting a condition of the teeth is one of the following: a baseline signal pattern indicating that each tooth is correctly positioned; and a divergent signal pattern diverging from the baseline signal pattern and indicating that at least one tooth is incorrectly positioned.

[0013] According to an additional or alternative embodiment, the signal mode is a sound mode.

[0014] According to additional or alternative embodiments, the transmitter and receiver pair includes a transmitter and receiver arranged proximate to a plane of the step-comb interface.

[0015] According to additional or alternative embodiments, the transmitter and receiver pair comprises an ultrasound transmitter.

[0016] According to an additional or alternative embodiment, the transmitter and receiver pair comprises a transmitter and a receiver respectively connected to the outermost teeth of the comb plate.

[0017] According to additional or alternative embodiments, the divergent signal pattern diverges from the baseline signal pattern in at least one of frequency, amplitude, and shape.

[0018] According to additional or alternative embodiments, the detection system is further configured to determine whether the divergent signal pattern is one of: indicating that at least one tooth is incorrectly positioned such that the comb plate requires attention and no escalator stop is warranted, and indicating that at least one tooth is incorrectly positioned such that an escalator stop is warranted.

[0019] According to additional or alternative embodiments, the detection system is further configured to perform an escalator stop.

[0020] According to the disclosed aspects, a method of operating a detection system for an escalator system is provided, in which a moving step including a groove passes through a comb plate at a step-comb plate interface, where each tooth of the comb plate passes through a corresponding groove when each tooth is correctly positioned. The method includes performing communication of a transmitter and a receiver pair, obtaining a signal pattern from the communication of the transmitter and the receiver pair, wherein the signal pattern partially reflects the condition of the teeth, and determining whether the signal pattern is one of the following: a baseline signal pattern indicating that each tooth is correctly positioned; and a divergent signal pattern, the divergent signal pattern diverging from the baseline signal pattern and indicating that at least one tooth is incorrectly positioned.

[0021] According to additional or alternative embodiments, determining includes determining whether the divergent signal pattern diverges from the baseline signal pattern in at least one of frequency, amplitude, and shape.

[0022] According to additional or alternative embodiments, determining includes determining whether the divergent signal pattern is one of: indicating that at least one tooth is incorrectly positioned such that the comb plate requires attention and no escalator stop is warranted; and indicating that at least one tooth is incorrectly positioned such that an escalator stop is warranted.

[0023] According to additional or alternative embodiments, the method further comprises performing an escalator stop.

[0024] Additional features and advantages are achieved through the technology of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be part of the claimed technical concept. In order to better understand the disclosure with advantages and features, reference is made to the specification and to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] For a more complete understanding of this disclosure, reference is now made to the following brief description, taken in conjunction with the accompanying drawings and detailed description, wherein like reference numerals represent like parts:

[0026] Figure 1 is a perspective view of an escalator system according to an embodiment;

[0027] Figure 2 According to the embodiment Figure 1 An enlarged perspective view of a landing of an escalator system;

[0028] Figure 3 is a schematic diagram of components of a detection system for use with an escalator system according to an embodiment;

[0029] Figure 4 According to the embodiment Figure 3 Graphical depiction of the baseline and divergent signal patterns of the detection system;

[0030] Figure 5 is a schematic diagram of teeth of a comb plate that are out of position but do not necessarily require an escalator stop according to an embodiment;

[0031] Figure 6 is a schematic diagram of teeth of a comb plate that are out of position and may require an escalator to be stopped, according to an embodiment; and

[0032] Figure 7 is a flow chart illustrating a method of operating a detection system of an escalator system according to an embodiment. DETAILED DESCRIPTION

[0033] In escalator technology, a comb plate is a safety item that ensures that parts of a passenger's body or other materials do not get caught in the transition between the moving steps and the floor plate. The main factor for a comb plate to be effective is that all teeth of the comb plate are in good condition and that the combs are correctly attached to the comb plate. Currently, there is no system to monitor the condition of the teeth of a comb plate or of the comb plate as a whole, other than manual inspection. Such inspections rely entirely on analysis by the corresponding technician.

[0034] Therefore, as will be described below, a method and system for monitoring the condition of the teeth of a comb plate of an escalator or moving walkway is provided. A transmitter, such as an ultrasonic transmitter or another similar transmitter, is connected to the side of the comb plate, and a receiver for the transmitter is connected to the opposite side of the comb plate. The signal transmitted by the transmitter and received by the receiver will have a certain signal pattern that will be associated with the condition of the teeth of the comb plate and reflect the condition of the teeth of the comb plate. When the teeth of the comb plate are in good condition, the signal pattern will have a corresponding baseline waveform that can be recognized by the processor. In contrast, when one or more of the teeth of the comb plate are not in good condition (i.e., because it / they are bent), the signal pattern will diverge from the baseline waveform, and the processor will recognize that this divergence indicates a problem that needs to be solved, such as by shutting down the escalator or walkway.

[0035] refer to Figure 1, an escalator 10 is provided. In the subsequent description, it should become apparent that the invention is applicable to other passenger conveyor systems, such as moving walkways. The escalator 10 generally includes a truss 12 extending between a lower landing 14 and an upper landing 16. A plurality of sequentially connected steps or pallets 18 are connected to a step chain 20 and travel through a closed loop path within the truss 12. A pair of handrails 22 are provided on either side of the escalator 10, wherein each handrail 22 includes a movable handrail 24. A drive machine 26 or drive system is typically located in a machine space 28 below the upper landing 16. An additional machine space 28' may be located below the lower landing 14. The drive machine 26 is configured to drive the pallet 18 and / or handrail 24 via the step chain 20. Under normal operating conditions, the drive machine 26 operates to move the pallet 18 in a selected direction at a desired speed.

[0036] The pallet 18 makes a 180 degree heading change in a turning area 19 located below the lower landing 14 and the upper landing 16. The pallet 18 is pivotally attached to a step chain 20 and runs along the closed loop path of the step chain 20 from one landing to another and back again.

[0037] The drive machine 26 includes a first drive member 32, such as a motor output sheave, connected to a drive motor 34 through a drive belt reduction assembly 36, which includes a second drive member 38, such as an output sheave, driven by a tension member 39, such as an output drive belt. In some embodiments, the first drive member 32 is a driving member and the second drive member 38 is a driven member.

[0038] As used herein, in various embodiments, the first drive member 32 and / or the second drive member 38 can be any type of rotating device, such as a sheave, pulley, gear, wheel, sprocket, cog, pinion, etc. In various embodiments, the tension member 39 can be configured as a chain, a belt, a cable, a strap, a band, a strip, or any other similar device that operatively connects two elements to provide a driving force from one element to another. For example, the tension member 39 can be any type of interconnecting member that extends between the first drive member 32 and the second drive member 38 and operatively connects the first drive member 32 and the second drive member 38. In some embodiments, as Figure 1As shown in , the first drive member 32 and the second drive member can provide a belt reduction. For example, the first drive member 32 can be about 75 mm (2.95 inches) in diameter, while the second drive member 38 can be about 750 mm (29.53 inches) in diameter. For example, the belt reduction allows the replacement of the sheave to change the speed of a 50 or 60 Hz electrical supply power application, or different step speeds. However, in other embodiments, the second drive member 38 can be substantially similar to the first drive member 32.

[0039] As described, the first drive member 32 is driven by the drive motor 34 and is therefore configured to drive the tension member 39 and the second drive member 38. In some embodiments, the second drive member 38 may be an idler gear or similar device driven by the operative connection between the first drive member 32 and the second drive member 38 through the tension member 39. The tension member 39 travels around a loop set by the first drive member 32 and the second drive member 38, which may be referred to as a small loop hereinafter. The small loop is provided for driving a larger loop consisting of the step chain 20 and is driven by, for example, an output sheave 40. Under normal operating conditions, based on the movement speed of the first drive member 32 as driven by the drive motor 34, the tension member 39 and the step chain 20 move together.

[0040] The escalator 10 also includes a controller 115 in electronic communication with the drive motor 34. As shown, the controller 115 can be located in the machine space 28 of the escalator 10 and is configured to control the operation of the escalator 10. For example, the controller 115 can provide a drive signal to the drive motor 34 to control the acceleration, deceleration, stopping, etc. of the pedal 18 through the step chain 20. The controller 115 can be an electronic controller including a processor and an associated memory, wherein the associated memory includes computer executable instructions that, when executed by the processor, cause the processor to perform various operations. The processor can be, but is not limited to, a single processor or multi-processor system of any one of a wide range of possible architectures, including field programmable gate arrays (FPGAs), central processing units (CPUs), application specific integrated circuits (ASICs), digital signal processors (DSPs), or graphics processing units (GPUs) hardware arranged homogeneously or heterogeneously. The memory can be, but is not limited to, random access memory (RAM), read-only memory (ROM), or other electronic, optical, magnetic, or any other computer-readable medium.

[0041] Although described herein as a specific escalator drive system and specific components, this is merely exemplary, and those skilled in the art will appreciate that other escalator system configurations may operate with the invention disclosed herein.

[0042] refer to Figure 2, Figure 1 The pedal 18 may be provided as a plurality of steps, and Figure 1 The lower and upper landings 14, 16 of the present invention may include a floor panel 201. The upper surface of each step (i.e., the tread 18) of the steps may be provided with a plurality of alternating grooves 202 and wedges 203 extending in the conveying direction C. A comb plate 210 is arranged adjacent to the floor panel 201 on a side of the floor panel 201 facing the steps. The comb plate 210 includes a plurality of teeth 211 extending parallel to the conveying direction C. The teeth 211 are arranged in a staggered relationship with the wedges 203 of the steps and extend into the grooves 202.

[0043] refer to Figure 3 and Figure 4 , an escalator system 301 is provided. The escalator system 301 includes a comb plate 310 and a moving step 320. The comb plate 310 includes teeth 311. The moving step 320 includes grooves 321 and can be driven along the conveying direction to pass through the comb plate 310 at a step-comb plate interface 330. At this step-comb plate interface 330, when each tooth 311 is correctly positioned (i.e., when each tooth 311 is not bent, broken or loose), each tooth 311 passes through the corresponding groove 321. The escalator system 301 also includes a detection system 340, and the detection system 340 includes a transmitter and receiver pair 350 and a processor 351, such as Figure 1 Controller 115 or a dedicated controller.

[0044] The detection system 340 is configured to determine a signal pattern 401 resulting from the communication of the transmitter and receiver pair 340 and partially reflecting the condition of the tooth 311 (see Figure 4 ) is one of the baseline signal pattern 410 and the divergent signal pattern 420. The baseline signal pattern 410 may be identified by the detection system 340 (i.e., by the processor 351) as indicating a condition in which each tooth 311 of the comb plate 310 is correctly positioned. The divergent signal pattern 420 may be identified by the detection system 340 (i.e., by the processor 351) because the divergent signal pattern 420 diverges from the baseline signal pattern 410 and indicates a condition in which at least one tooth 311 of the comb plate 310 is incorrectly positioned.

[0045] The processor 351 of the detection system is operably coupled to the transmitter and receiver pair 340 and includes a processing unit, a networking unit through which the processing unit communicates with the transmitter and receiver pair 340 and with external devices and a memory. The memory has executable instructions stored thereon that, when executed, cause the processing unit to operate as described herein. The following description will generally refer to the processor 351.

[0046] According to an embodiment, the transmitter and receiver pair 350 of the detection system 340 may include a transmitter 3501 and a receiver 3502, both of which are coupled to and in communication with the processor 351. The transmitter 3501 may be provided as an ultrasound transmitter, and the receiver 3502 may be provided as a receiver configured to receive ultrasound signals from the transmitter 3501. In these or other cases, the signal pattern 401 may be a sound waveform pattern.

[0047] According to further embodiments, the transmitter 3501 and the receiver 3502 of the transmitter and receiver pair 350 may be arranged at a position close to the plane P of the step-comb interface 330. In these or other cases, as Figure 3 As shown in , the transmitter 3501 and the receiver 3502 can be respectively connected to the outermost teeth 311 of the comb plate 310.

[0048] Continue to refer Figure 3 and Figure 4 , the divergent signal pattern 420 may diverge from the baseline signal pattern 410 in at least one or more of frequency, amplitude, and shape or waveform.

[0049] During normal operation when the escalator system 301 is running and each tooth 311 of the comb plate 310 is correctly positioned (i.e., when each tooth 311 is not bent, broken, or loose), the transmitter 3501 periodically sends a signal, such as an ultrasonic signal, to the receiver 3502. Because each tooth 311 is correctly positioned and passes through the corresponding groove 321, the passage of the moving step 320 by the comb plate 310 tends to produce a specific and predictable range of sounds at the step-comb plate interface 330. These sounds may or may not interact with the ultrasonic signal, such as through interference or resonance, so that the signal ultimately received by the receiver 3502 will tend to be regular, and therefore can be considered as a baseline signal pattern 410. The processor 351 can be trained to recognize the baseline signal pattern 410.

[0050] In the event that at least one tooth 311 is incorrectly positioned, the passage of the moving step 320 by the comb plate 310 at the step-comb plate interface 330 will tend to produce a unique range of sounds that depends on various factors, such as the number of incorrectly positioned teeth 311, the nature of the incorrect positioning of the teeth 311, and the degree to which the incorrectly positioned teeth 311 are not in their correct positions. These unique sounds will interact with the ultrasonic signal, such as through unique interference or resonance patterns, whereby the signal ultimately received by the receiver 3502 will diverge from the baseline signal pattern 410 in at least one or more of frequency, amplitude, and shape or waveform. The processor 351 can be trained to thereby recognize this signal as a diverging signal pattern 420.

[0051] refer to Figure 5 , the divergence of the divergent signal pattern 420 from the baseline signal pattern 410 can be read by the processor 351 as indicating that at least one tooth 311 is incorrectly positioned to the extent that the comb plate 310 requires attention, but no escalator stop is warranted. An example of this instance is Figure 5 It is described in Figure 5 The teeth 311 are depicted slightly offset from their normal angle. As the moving step 320 passes the comb plate 310 at the step-comb plate interface 330, the offset teeth 311 gently rub against the walls of the groove 321 and produce a continuous grinding sound that may or may not interact with the ultrasonic signal as described above.

[0052] refer to Figure 6 , the divergence of the divergent signal pattern 420 from the baseline signal pattern 410 can be read by the processor 351 as indicating that at least one tooth 311 is incorrectly positioned to such an extent that an escalator stop is warranted. An example of this is shown in Figure 5 It is described in Figure 5 A tooth 311 is depicted as loose. As the moving step 320 passes the comb plate 310 at the step-comb plate interface 330, the loose tooth 311 bounces around and generates a slightly randomized acoustic wave that interacts with the ultrasonic signal described above. In the event that the divergence of the divergent signal pattern 420 can be read as indicating that at least one tooth 311 is incorrectly positioned to such an extent that an escalator stop is warranted, the processor 351 can be further configured to execute an escalator stop.

[0053] Return to reference Figure 3 and Figure 4 , and additionally refer to Figure 7, a method of operating a detection system (such as the detection system 340 described above) is provided. The method includes performing communication of a transmitter and receiver pair 350 (box 701) and obtaining a signal pattern 401 from the communication of the transmitter and receiver pair 350, wherein the signal pattern 401 partially reflects the condition of the tooth 311 (box 702). The method also includes determining whether the signal pattern is one of the following: a baseline signal pattern 410 (box 703) and a divergent signal pattern 420 (box 704), wherein the baseline signal pattern 410 indicates that each tooth 311 is correctly positioned, and the divergent signal pattern 420 diverges from the baseline signal pattern 410 in at least one of frequency, amplitude, and shape or waveform and thus indicates that at least one tooth 311 is incorrectly positioned. The determination of block 704 may also include determining whether the divergent signal pattern 420 is one of: indicating that at least one tooth is incorrectly positioned such that the comb plate requires attention and no escalator stop is warranted (block 7041); and indicating that at least one tooth is incorrectly positioned such that an escalator stop is warranted (block 7042). In the event that the divergent signal pattern 420 is determined in block 7042 to be incorrectly positioned such that an escalator stop is warranted, the method may also include performing an escalator stop (block 705).

[0054] The technical effect and benefit of the present disclosure is to provide a detection system for use with an escalator system to detect teeth of a comb plate that are out of place, loose, bent, broken, etc. With such a detection system, in addition to improved safety, productivity gains may also be achieved due to the possibility of increased time between manual inspections by a technician.

[0055] The corresponding structures, materials, actions and equivalents of all parts or steps plus function elements in the following claims are intended to include any structure, material or action for performing a function in combination with other claimed elements as specifically claimed. The description of the present disclosure has been presented for the purpose of illustration and description, but it is not intended to be exhaustive or limited to the technical concepts of the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the disclosure. The embodiments are selected and described in order to best explain the principles and practical applications of the disclosure, and to enable other persons of ordinary skill in the art to understand the disclosure of various embodiments with various modifications as suitable for the specific purposes envisioned.

[0056] Although the preferred embodiments of the present disclosure have been described, it will be understood that various improvements and enhancements may be made by those skilled in the art, both now and in the future, which improvements and enhancements fall within the scope of the appended claims. These claims should be construed to maintain the proper protection for the disclosure first described.

Claims

1. An escalator system, comprising: a comb plate including teeth; a moving step including grooves and being drivable to pass over the comb plate at a step-comb plate interface where each tooth passes through a corresponding groove when each tooth is properly positioned; as well as A detection system includes a transmitter and receiver pair and is configured to determine whether a signal pattern resulting from communications of the transmitter and receiver pair and reflecting in part a condition of the teeth indicates that at least one tooth is improperly positioned.

2. The escalator system according to claim 1, wherein: The signal mode is a sound mode.

3. The escalator system according to claim 1, wherein: The transmitter and receiver pair includes a transmitter and a receiver disposed proximate a plane of the step-comb interface.

4. The escalator system according to claim 1, wherein: The transmitter and receiver pair includes an ultrasound transmitter.

5. The escalator system according to claim 1, wherein: The transmitter and receiver pair includes a transmitter and a receiver respectively connected to the outermost teeth of the comb plate.

6. The escalator system according to claim 1, wherein: At least one of a frequency, an amplitude, and a shape of the signal pattern indicates that the at least one tooth is improperly positioned.

7. The escalator system according to claim 1, wherein: The detection system is further configured to determine whether the signal pattern is one of the following: indicating that the at least one tooth is incorrectly positioned such that the comb plate requires attention and no escalator stoppage is warranted, and An indication that the at least one tooth is incorrectly positioned is provided such that a stop of the escalator is warranted.

8. The escalator system according to claim 7, wherein: The detection system is also configured to perform a shutdown of the escalator.

9. An escalator system, comprising: a comb plate including teeth; a moving step including grooves and being drivable to pass over the comb plate at a step-comb plate interface where each tooth passes through a corresponding groove when each tooth is properly positioned; as well as A detection system comprising a transmitter and receiver pair and configured to determine whether a signal pattern resulting from communication between the transmitter and receiver pair and partially reflecting a condition of the tooth is one of the following: a baseline signal pattern indicating that each tooth is properly positioned, and A divergent signal pattern diverges from the baseline signal pattern and indicates that at least one tooth is improperly positioned.

10. The escalator system according to claim 9, wherein: The signal mode is a sound mode.

11. The escalator system according to claim 9, wherein: The transmitter and receiver pair includes a transmitter and a receiver disposed proximate a plane of the step-comb interface.

12. The escalator system according to claim 9, wherein: The transmitter and receiver pair includes an ultrasound transmitter.

13. The escalator system according to claim 9, wherein: The transmitter and receiver pair includes a transmitter and a receiver respectively connected to the outermost teeth of the comb plate.

14. The escalator system according to claim 9, wherein: The divergent signal pattern diverges from the baseline signal pattern in at least one of frequency, amplitude, and shape.

15. The escalator system according to claim 9, wherein: The detection system is further configured to determine whether the divergent signal pattern is one of the following: indicating that the at least one tooth is incorrectly positioned such that the comb plate requires attention and no escalator stoppage is warranted, and An indication that the at least one tooth is incorrectly positioned is provided such that a stop of the escalator is warranted.

16. The escalator system according to claim 15, wherein: The detection system is also configured to perform a shutdown of the escalator.

17. A method of operating a detection system for an escalator system in which a moving step including a groove passes through a comb plate at a step-comb plate interface where each tooth of the comb plate passes through a corresponding groove when each tooth is correctly positioned, the method comprising: performing communication between a transmitter and a receiver pair; deriving a signal pattern from said communication of said transmitter and receiver pair, wherein said signal pattern reflects in part a condition of said tooth; as well as Determine if the signal mode is one of the following: a baseline signal pattern indicating that each tooth is properly positioned, and A divergent signal pattern diverges from the baseline signal pattern and indicates that at least one tooth is improperly positioned.

18. The method according to claim 17, wherein: The determining includes determining whether the divergent signal pattern diverges from the baseline signal pattern in at least one of frequency, amplitude, and shape.

19. The method according to claim 17, wherein: The determining includes determining whether the divergent signal pattern is one of the following: indicating that the at least one tooth is incorrectly positioned such that the comb plate requires attention and no escalator stoppage is warranted, and An indication that the at least one tooth is incorrectly positioned is provided such that a stop of the escalator is warranted.

20. The method of claim 19, further comprising performing a shutdown of the escalator.

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