HK40011122A - Monitoring the mechanical state of an escalator or a moving walkway - Google Patents

Description

Monitoring scheme for mechanical state of escalator or moving walkway

Technical Field

The invention relates to a method for detecting and monitoring the mechanical state of an escalator or moving walkway, and to an escalator or moving walkway having at least one detection device for detecting and monitoring the mechanical state.

Background

It is known that escalators and moving walks have detection devices for detecting and monitoring the mechanical state in order to ensure safe operation of these people moving devices. For example, CN201132723Y discloses an escalator, the step belt of which is monitored by a sensor. When the steps have separated from the step band, a gap is created, and the sensor detects the gap and outputs a corresponding signal to the escalator controller. The escalator controller stops the step band immediately after the input signal.

JP2010269884A discloses an escalator with a detection device for detecting and monitoring the mechanical state of the step band. Here, images of the escalator steps are taken and evaluated by two cameras.

In JP 2009190818A, the gap between the step band and the base plate is monitored by a plurality of sensors.

A high monitoring density, or more precisely monitoring as many key points of the escalator or moving walkway as possible, requires a large number of sensors. This has the disadvantage that such detection devices are very expensive, and in particular that each additional sensor increases the susceptibility of the entire system or escalator or moving walkway to failure with a high monitoring density.

Disclosure of Invention

It is therefore an object of the present invention to provide a method and a detection device for detecting and monitoring the mechanical state of an escalator or moving walkway, which allow a high monitoring density, but the detection device is inexpensive and ensures high reliability and usability. An escalator or a moving walkway.

This object is achieved by a method for detecting and monitoring the mechanical state of an escalator or moving walkway having at least one revolving belt and at least one detection device. The method comprises at least the following method steps performed by the detection device:

at least one aerial image of at least one segment of the revolving band is generated or created,

at least one region of the aerial image is selected,

comparing the selected area with at least one comparison area, which is defined by three-dimensional coordinates and represents a virtual space that can uniquely correspond to the selected area, an

If the selected range differs from the comparison area by more than the predetermined boundary, an alarm signal is generated.

Since the method compares the position of points, surfaces and edges of the aerial image with the virtual space, accurate and therefore interference-free monitoring depends on how the image and the comparison region spatially correlate.

According to the invention, the comparison area is simply and accurately corresponded to the selected area by the reference mark. These reference marks correspond to the fixed parts of the escalator or moving walkway. Thus, the reference marker can be recognized as a reference marker image in the aerial image. In practice, the markings are arranged on a fixed area, for example on a truss or on a rail of a revolving belt, or the area has a unique appearance in relation to the design, for example a conspicuously protruding screw head. In the comparison area, for example defined by spatial coordinates, reference markers, hereinafter referred to as virtual reference markers, are also stored. In this case, the correspondence is very simple because the virtual reference mark and the reference mark image can be used as a zero point of the spatial coordinate system of the image and the comparison area.

By means of this method of generating a spatial image of the instantaneous actual state, comparing the image with a corresponding virtual space and analyzing it, a large number of critical points can be monitored simultaneously by means of a single detection device.

The present invention is based on the following findings: most of the escalators or moving walks are accompanied by spatial displacement of the moving parts from the direction of movement or path of movement in which they are set, which is critical for safety or for damage-related events. In particular, this relates in particular to a turn-around arranged step belt of a turn-around arranged step belt or pallet belt of a moving walkway of an escalator and to the side of the step belt or pallet belt arranged in parallel turn-around handrails or handrail belts or limb handrails. For reasons of better readability, these components which can be moved in a revolving manner relative to the fixed part of the escalator or moving walkway are referred to below as revolving belts.

The fixed parts of an escalator or moving walkway include, for example, a load-bearing structure or truss and components fixed therein, such as ribs, guide rails, trim components of the guardrail base, etc.

The following are examples in which an impending safety critical event and/or incipient damage event from spatial displacement of a moving component may be detected by its intended direction of motion. These events are not exhaustive. There may be various other reasons for spatial displacement of the moving part from its intended direction of movement.

The first possible event involves the lowering or raising of the tread surface, e.g. a step or pallet, from right to left. In other words, the foot tread surface is skewed transverse to the direction of travel. The reason for such a skewed placement may be, for example, a broken step shaft, a reduced diameter due to wear or breakage of the tug or chain roller, a broken step or pallet panel, a damaged step sleeve, a broken connection between the pallet or step and the step band or pallet band chain, or an enlarged chain or drag roller due to contamination on the running surface. It is also possible that the guide rail has sunk.

Excessive deflection of the tread surface can not only disturb the user of the escalator or moving walkway, but can also lead to the tread surface colliding with the comb plate or to damage to the guide rails and the base plate.

For example, to detect the skewed placement of the tread surface, the spatial position of the lower edges of the side panels of the steps and pallets can be monitored. In this case, these lower edges are selected from the aerial image and compared with the comparison area. Strictly speaking, the spatial coordinates of the detected points of the selected area of the spatial image are compared with the spatial coordinates that can be recalled from the electronic data memory. By comparison, the spatial deviation of the image and the coordinates from each other is determined. It is important that the comparison area can be unambiguously assigned to the selected area. The correspondence relationship will be described in more detail below.

Once the spatial deviation of the selected region exceeds a predetermined virtual space defined by boundary values or the selected region protrudes therefrom, it can be assumed that an event to be monitored occurs, in this example a deflection of the foot tread region. This means that an excessive deflection exceeding the boundary value is detected and an alarm signal is generated by the detection means. The alarm signal may trigger various actions. The alarm signal can be forwarded to the escalator control, which then stops the revolving belt. For example, the detection device may also have an optical and/or acoustic output device that alerts the user.

If the entire footboard element is missing, the region to be selected and therefore the spatial coordinates of the selected region are missing on the aerial image, which leads to a maximum deviation or an exceeding of the boundary values compared to the comparison region. In this case, the control of the escalator or moving walkway must immediately initiate the emergency braking and fix the tread or pallet belt.

Furthermore, the traction rollers or chain rollers of the step band or pallet band can be selected from the aerial image and monitored accordingly. If the traction or chain rollers are missing or have an outer diameter that is too large, the selected region (e.g., the cylindrically defined virtual space) is inconsistent with a comparison region called from the data store that may uniquely correspond to the selected region.

In this case, the spatial image is preferably selected to be a region which, in the case of a possible event to be monitored, has a particularly strong deviation from the corresponding comparison region and thus represents a distinct surface or edge of the possible event.

A second possible event involves deflection of the tread surface. In this case, the tread surface of the tread surface is indeed horizontally disposed, but the side panels of the pallets or steps are not parallel to the guardrail base and the floor, or the front and rear edges of the tread surface are not perpendicular to the floor. The cause of such skew may be a defective step wrap on the left or right side. Or due to asymmetric wear on one side of the step or pallet belt, the chain length of one of the conveyor chains may be greater than the chain length of the other side. Furthermore, a broken connection (step axle) between the step or pallet and the conveyor chain or a defective slide, which holds the step belt or pallet belt at a defined distance from the base plate, can also lead to a skewed position of the tread surface.

For example, to detect the deflection of the treads, the spatial position of the side panels or the front or rear edges of the steps and pallets treads may be monitored. In this case, these regions are selected from the aerial image and compared with the comparable regions, which may correspond.

On the aerial image, but not only the area of the revolving belt is shown, but also a stationary component, such as a section of the base plate or of the guide rail. To control the distance and angular position or parallelism of the side panels, the front or rear edges of the treads of the steps and pallets can be measured and evaluated using values that can be recalled from the data storage comparison area.

A third possible event involves a so-called step skew, as described in detail in KR 920007689U, for example. There is a larger clearance between the rail and the step due to defects or damage. The user must take one step before he leaves the step band and must step on the comb plate. In this case, the user steps on the front edge of the step (edge between the tread surface and the mounting surface), and the rear edge may rise due to a large clearance in the system and then move toward the comb plate. The larger gaps are typically the result of wear of the step chain, chain pins, step axles, step wraps, and step bosses of the steps.

For example, to detect the deflection of the tread surface, the spatial position of the front or rear edges of the tread surfaces of the steps and pallets can be monitored. In this case, these regions are selected from the aerial image and compared with the comparable regions, which may correspond.

A fourth possible event involves detecting an increase in the gap between the step or pallet and the substrate. This critical area is caused by many accidents between the fixed guardrail base and the moving steps or pallets, which are caused by squeezing shoes, fingers, clothing, etc. In particular for escalators in the transition region from a deflection region to a horizontal region, in which the steps additionally move vertically relative to one another, it is possible to involve articles such as soft foam materials like PCCR (proprietary closed cell). The gap between the steps and the floor should ideally be 3 mm. In the case of a cramped shoe/garment/finger, the gap increases. On the aerial image, the enlargement of the gap or foreign matter (shoes, clothes, etc.) as well as the movement of the step belt or pallet belt from the left side to the right side (or vice versa) and the bending of the bottom plate can be seen. This possible event is detected, for example, by monitoring the spatial position of the lateral edges of the tread surfaces of the steps and pallets. In this case, these regions are selected from the aerial image and compared with the comparable regions, which may correspond. Once a deviation is detected, for example, an alarm signal is sent to the escalator controller and the escalator is stopped immediately before the components of the article are further rolled in or cut off at the comb plate.

A fifth possible event involves the transition from a tread surface to a tread surface (the void between the two tread surfaces). Once garments or other items are positioned in the void between the treads, they are displayed on the aerial image. When the face of the edge region of the foot tread is selected, the shape and position of the selected region of the spatial map deviates from the associated comparison region and a problem is identified.

A sixth possible event involves handrail stress around the revolving handrail or the revolving belt. In this case, the detection device is arranged such that a segment of the handrail return segment is also detected together. If the handrail is to be monitored, the detection device is preferably arranged in the escalator, for example, in the lower transition region from the horizontal section to the deflecting section, since the revolving belt sags in the first occurring upper transition region due to the gravity and the arrangement of the handrail drive. A small sagging is necessary, since otherwise the revolving belt is stretched too tightly and has a high wear. There is a risk that the friction between the handrail drive and the revolving belt is too small, due to too little stress and correspondingly large sagging. The slack recorded in the aerial image is evaluated, for example, by a selected curved longitudinal edge of the handrail belt, which at the boundary must lie within a range predetermined by the comparison area.

With a suitable arrangement of the detection means, the above-mentioned possible events can be detected by means of a single aerial image of the detection means at the monitoring instant by selecting the respective regions of the aerial image and comparing them with the correspondingly comparable regions. In this case, since several possible events can be checked by comparing the image with the comparison area, each selected area or each protruding area and edge, for example the lower edge of a step panel having multiple purposes, can be checked.

The selected area is a particular area of the footboard elements or a handrail part of the belt protruding the arrises or turns around. The spatial positions of the zeros of the regions in the aerial image are compared by comparing them to predetermined boundaries of their expected positions. Based on the predetermined boundary (allowable deviation), the comparison area is always a virtual space in which the spatial arrangement or position of points, edges or areas of the aerial image is determined.

The predetermined boundary of the comparison area is exceeded when the selected area protrudes from the virtual space of the comparison area at least one position. If an edge or region is missing from the selected region, this is also considered to exceed the predetermined boundary. The same applies to edges or regions of the selected region that are arranged outside the predetermined angular tolerance boundary and are not parallel to corresponding edges or regions of the virtual space.

It goes without saying that the above-described detection devices are repeatedly represented spatially during the operation of the escalator or moving walkway, and these are evaluated in order to achieve sufficient operation monitoring. The chronological order of the individual images and the number of images per time unit are based on legislator's regulations and standards, operator's requirements and monitoring goals. Thus, for example, during the stationary time of an escalator or moving walkway, four images per hour are taken during so-called creep (unloading at reduced speed), while one image per minute is taken during nominal speed and evaluated. Preferably, the detection means are controlled such that the entire belt is imaged on the image during a complete rotation of the revolving belt. The selection and comparison may also be very different for the various regions of the image. For example, the position of the footboard elements in each aerial image can be compared with the comparison area, while the handrail belt sagging is only checked for every hundred images.

It is not necessary to evaluate each aerial image or compare a selected region to a comparison region. For example, a series of aerial images of a segment of the band of revolutions may be generated or created and selected by comparing the distances of the surfaces and edges on the aerial image with at least one reference marker image that best matches the associated comparison region and its virtual reference. Therefore, a correction of the aerial image may not be necessary, since the region selected from the best matching aerial image has at least approximately the same position relative to the reference marker image as the comparison region associated with the virtual reference marker.

In order to be able to further reduce the required computational power, it is advantageous if the reference mark image is approximately always reproduced at the same position in each aerial image. To achieve this, a position-determining device arranged on a stationary part of the escalator or moving walkway can be provided. This detects a distinct surface, edge or marking of the footboard element or handrail part of the revolving belt. Upon detection, the position determining device generates a trigger for triggering the image capture device based on the detected current position of the surface, edge or mark of the position determining device. Thus, for example, the image of the tread elements of the revolving belt to be detected is always produced in the same position relative to the fixed part of the escalator. In other words, although the figures show different footboard elements, all footboard elements are acquired in almost exactly the same position with respect to the co-imaged stationary part. Thus, if a sufficient match or congruency is established by a comparison of the positions of the virtual reference mark and the reference mark image, only a very small correction has to be made or a comparison with the comparison area can be made directly. Accordingly, correction of distortions due to different shooting angles of the aerial image and the comparison area can be omitted, which is necessary if the positional deviation is too large.

Preferably, the detection means comprise an electronic processing unit. With this, for example, selection of a region of the aerial image and correspondence with the comparison region can be performed. The processing unit may further comprise an analyzing unit. By means of the evaluation unit, the position of the regions or edges of the selected region can be evaluated with respect to the boundaries of the comparison region, and a position reserve can be determined. Based on the determined location reserve and/or by analyzing a history of several previously determined, stored location reserves, a next maintenance appointment may be determined. Thus, emerging lesions that may lead to serious consequential lesions are discovered at an early stage and their development is monitored.

From the classification of the analysis unit as a maintenance-related position reserve, the possible work steps to be performed and the maintenance material that may need maintenance can be determined. This can also be done automatically, if appropriate, for example by means of an analysis unit.

The comparison area can be generated in various ways and stored, for example, in a data memory of the detection device or in a control of the escalator or moving walkway. The comparison area may also be stored in an external data storage, such as a usb disk, an external hard drive mobile phone, through an internet database or a world wide web cloud, and may be recalled from these storage media.

In order to generate and store the comparison region, for example, learning travel may be performed using an envelope element representing the maximum allowable deviation, and a spatial image thereof may be stored in one of the above-described data memories.

Of course, the comparison area and the components of the escalator or moving walkway can also be built on a 3D-CAD system and stored in the data memory.

The learning operation can also be carried out using the revolutionary frequency bands provided for the operation and a spatial image of the frequency band region can be generated or created. Thereafter, a comparison area is generated from the aerial image by defining boundary values in the form of three-dimensional coordinates as distinct edges and surfaces of the aerial image, and defining a virtual space larger than the boundary values as the comparison area.

Furthermore, a test driver with at least one test element can be implemented to check the operability of the detection device. The test element is designed either to be mounted in place of a segment of the revolving belt (for example instead of a step) or to be designed as an attachment for temporary fixing to the revolving belt (for example as a cuff for a handrail belt attachment). The test element is dimensioned such that it protrudes at least one point from the comparison area. Therefore, when evaluating the aerial image of the test element by selection and comparison, the detection device has to output an alarm signal.

In order to carry out the above-described method for detecting a state, there are escalators or moving walkways with revolving belts and detection devices for detecting and at least one monitoring of the machine condition. The detection device comprises at least one image recording device, by means of which an aerial image can be generated. The aerial image according to the present document is a virtual 3D model. More precisely, such a spatial mapping is a true scale shot structure which represents the digitized version in three dimensions as much as possible, wherein the individual points of the spatial mapping in the virtual space are defined by three-dimensional and/or vector coordinates.

By means of the detection device, the state of the revolving belt and/or the arrangement of the area of the belt relative to the fixed part of the escalator or moving walkway can be detected by means of at least one aerial image of a section of the revolving belt. The marking area or the edge of the part captured on the image can be selected by the processing unit of the detection device and can be compared with a three-dimensional comparison area stored in the data memory. If the selected area differs from the comparison area by more than a predetermined boundary, an alarm signal is generated by the detection means.

As already mentioned, the detection device can comprise a position detection device which is arranged on a fixed part of the escalator or moving walkway, by means of which a distinct region, edge or marking of the tread or handrail part can be detected. By means of the position detection device, a trigger for triggering the image recording device is provided for generating the current position of the detection surface, edge or marking of the position detection device.

The detection device or its image recording device can be arranged between the feed of the revolving belt and the return of the revolving belt. The detection device can also have a plurality of image recording devices which are distributed over the length of the escalator or moving walkway, preferably in the region of critical points of the escalator or moving walkway.

Dirt accumulates on escalators and moving walkways, usually during the operating phase. This can also be established on the image recording device. If the layer of dirt becomes too dense, this can cover and affect the emitting device, e.g., the laser of a laser scanner, and the camera, e.g., the photocell of a laser scanner. The image recording device can therefore be provided with a transparent protective cover which covers the transmitting device and the image recording device of the image recording device from above. Furthermore, the detection device can have a cleaning device by means of which at least part of the surface of the transparent protective cover is periodically cleaned.

It should be understood that some of the possible features and advantages of the present invention have been described herein with reference to different embodiments. In particular, some features are described with respect to a method according to the invention and other features are described with respect to an apparatus according to the invention. Those skilled in the art will appreciate that these features can be combined, adapted or substituted as appropriate to arrive at further embodiments of the invention.

Drawings

Embodiments of the invention will now be described with reference to the accompanying drawings, which together with the description are not intended to limit the invention.

Fig. 1 shows an escalator with a detection device according to an embodiment of the invention.

Fig. 2 schematically shows the main method steps of the method according to an embodiment of the invention and the operating principle of the detection device with the aid of partial fig. 2A to 2C.

Fig. 3 shows the escalator steps as a segment of a revolving belt, by means of which the deflection relative to the set position is shown.

Fig. 4 shows a possible design of the envelope elements suitable for learning to travel.

The figures are purely diagrammatic and not true to scale. The same reference numbers in different drawings identify the same or functionally similar features.

Detailed Description

Fig. 1 shows a side view of an exemplary escalator 1, by means of which a person can be transported, for example, between two levels E1, E2. The escalator 1 has a load-bearing structure 2 in the form of a truss, which is shown only in its outline for the sake of clarity. The load bearing structure 2 houses the components of the escalator 1 and supports them within the building. These components include, for example, a guard rail 3 (only one visible in the side view) with a handrail 5 arranged in a revolving manner. The railing 3 is connected to the load-bearing structure 2 by a railing base 4. The handrail 5 or the turn 5 is driven by a friction drive 6, the friction drive 6 being operatively connected to a drive assembly 25 of the escalator 1. The correct stress of the handrail 5 is maintained by means of a handrail tensioning device 7, which is only schematically shown.

The escalator 1 also has two endless revolving conveyor chains 11, of which only one is visible from the side view. The two conveyor chains 11 are composed of a plurality of chain links. The two conveyor chains 11 can be moved along the travel path 8 in the direction of travel. The conveyor chains 11 are parallel to each other and spaced apart in a direction transverse to the direction of travel. In the end regions adjoining the horizontal planes E1, E2, the conveyor chain 11 is deflected by the diverting sprockets 15, 16.

Between the two conveyor chains 11, an arrangement of a plurality of tread elements 9 in the form of tread surfaces is arranged, which connect the conveyor chains 11 to one another transversely to the stroke 8. With the aid of the conveyor chain 11, the footboard elements 9 can be moved in the direction of travel along the travel path 8. The tread elements 9 guided on the conveyor chain 11 form a tread surface belt 10 or a revolving belt 10, wherein the tread elements 9 are arranged one behind the other along the travel path 8 and can be stepped on by the user at least in the conveying region 19. The revolving belt 10 is guided by schematically shown guide rails 12 and is supported against gravity. These guide rails 12 are fixedly arranged in the load-bearing structure 2.

To move the conveyor chain 11, the sprockets 16 of the upper level E2 are connected to the drive assembly 25. The drive assembly 25 is controlled by a controller 24 (which is only very schematically shown in fig. 1). The step band 10 forms together with the drive assembly 25 and the diverting wheels 15, 16 a conveyor for users and articles, the tread elements 9 being movable relative to the load-bearing structure 2 to which the fixtures in the building are firmly anchored.

As mentioned above, most safety-critical and/or damage-critical events in escalators 1 or moving walkways are accompanied by spatial displacement of the moving parts from the direction of movement in which they are set. Thus, in particular by monitoring the revolving belt 5, 10, for example the step belt 10 or the revolving handrail 5, the occurrence of damage can be detected. To achieve this, a detection device 20 is provided in the escalator 1, which detection device 20 comprises, in the present example, two image recording devices 21 and a processing unit 22. The image recording device 21 is arranged in a fixed manner on the structure 2 in the transition region between the horizontal sections of the escalator 1 arranged on the level planes E1, E2 and the inclined middle section of the escalator 1. Since, in particular, the forward part of the step band 10, which is loaded by the user, is to be monitored and evaluated, the image recording device 21 is arranged between the forward part and the return part of the step band 10 or of the revolving band 10. The image recording device 21 has a technically limited detection region α, which is schematically illustrated in fig. 1 by a dashed line and an angle α. The image recording device 21 can thus detect only one segment of the revolving belt 10.

The image recording device 21 arranged in the transitional region of the lower level E1 can additionally also detect the sagging 28 of the armrest 5. The sagging occurs exactly at this location due to the lack of stress of handrail tensioning device 7 on handrail 5 and the force of gravity.

The two image capture devices 21 communicate with a processing unit 22, the processing unit 22 being arranged in and connected to a control box of a controller 24. Of course, the detection device 20 may also comprise an image recording device 21 and a processing unit 22, which are arranged in a common housing. The processing unit 22 may also be implemented as a pure software application in the data memory of the computing unit and the controller 24. Of course, there are other possibilities to arrange the various parts of the detection device 20 distributed in the escalator 1.

Fig. 2 schematically shows, with reference to fig. 2A to 2C, method steps of a method performed together with a detection device 20 according to an embodiment of the invention.

As already indicated with reference to fig. 1, and also in fig. 2A, the image recording device 21 of the detection device 20 is also arranged in a positionally fixed manner relative to the guide rail 12 between the forward part 14 and the return part, not shown. The image photographing device 21 has a hemispherical transparent protection cover 23. In order to periodically clean them of dirt and dust, there is a cleaning device 18, which in this example is shown as a compressed air blast pipe.

Furthermore, fig. 2A shows a segment of the revolving belt 10, more precisely two tread elements 9 of the step band 10. One of the two footboard elements 9 has lost the traction roller 13, causing its tread 29 to deflect.

For the sake of clarity, the conveyor chains 11 arranged on both sides of the footboard elements 9 and the representations of the step shafts 26 connecting them and of the guide rails 12 supporting the conveyor chain rollers 42 are omitted (these components are shown in fig. 3). On the two rails 12 shown are traction rollers 13 of the footboard element 9. One of the guide rails 12 has a reference mark 30, which can be detected by the image recording device 21.

Since the image capture device 21 is always fixedly located in the same position, no position compensation is required between the reference mark 30 and the image capture device 21. However, during the generation or creation of the aerial image, the footboard element 9 is moved relative to the guide rail 12 and the image recording device 21, so that here a position compensation or correspondence represented by the spatial coordinates x, y, z is required. This may be accomplished by reference numeral 30 as described below.

In fig. 2B, an aerial image 40 of the segmented tread elements 9 shown in fig. 2A of the step band 10 is schematically shown by means of dashed lines or image points. Furthermore, the corresponding virtual space 41 is shown in dash-dot lines. The spatial image 40 is generated or created by an image capture device 21, which may be, for example, a laser scanner or a time-of-flight camera. The digital imaging device 21, which generates the digital spatial image 40, detects the three-dimensional structure and images the faces and edges of the structure by means of a plurality of image points P ', each defined by spatial image coordinates x', y ', z' and vector coordinates, starting from a virtual zero point.

The fixed components may also be displayed together. In this example, one section of the guide rail 12 and the reference mark 30 mounted on the guide rail 12 have been shown as reference mark image 30'. The virtual zero point may be, for example, the center of the reference mark image 30'.

The aerial image 40 is sent to the processing unit 22 (see fig. 1). In the processing unit 22, at least one region 27' of the aerial image 40 is then selected, for example, the image of the lower edge 27 of the rest step of the tread element 9. The selection is made according to criteria stored in the processing unit 22, for example, based on the region that deviates the most from its original or set position when wear or damage occurs.

The corresponding comparison area 27 "is called up from the electronic data memory 39 by the processing unit 22. For example, a part of the virtual space defined by the virtual coordinates x ', y ', z ', whose faces and edges correspond to the boundary-value-modified spatial image of a segment of the revolving band 10 in the starting position, can be retrieved from the data memory 39. The initial position of the segment should be considered as the home position before wear, damage and contamination cause a change in position. In the virtual space 41, a virtual reference mark 30 "is present. The virtual space 41 shown in fig. 2B is used only as an example, which may be used entirely as the comparison area 27 ″. For example, the entire virtual space 41 shown may be used as the comparison area 27 ". However, it is also possible to store only the individual spatially extended edges 27 or surfaces of the footboard elements 9 with respect to the virtual reference marking 30 "as comparison regions 27". Of course, other components of the revolving belt 10 may be imaged in the comparison area 27 ".

In addition, spatial image coordinates x ', y', z 'between the reference mark image 30' and uniquely identifiable points, for example the point P at which the step lower edge 27 is placed or the detected image point P 'of the selected region 27', can be determined in the processing unit 22. If, when an aerial image is generated or created, the point P of the foot element 9 has spatial coordinates x, y, z relative to the reference marking 30, the aerial image coordinates x ', y ', z ' of the image point P ' imaged on the aerial image 40 are logically identical to the spatial distance coordinates x, y, z relative to the reference marking 30 ' likewise imaged. Ideally, a uniquely identifiable point P is selected.

If the aerial image 40 is taken by the image capture device 21 at any given time, it is a pure coincidence if the selected region 27 ' of the aerial image 40 has exactly the same aerial image coordinates x ', y ', z ' relative to the reference landmark image 30 ' as the corresponding comparison region 27 "relative to the virtual reference marker 30". Thus, in a first step, the selected areas 27' are assigned to the respective comparison areas 27 ″.

Precisely, by means of the reference marker image 30 'and the virtual reference marker 30 ", for example, the spatial position difference Δ of the image point P' and the corresponding virtual point P" of the respective comparison area 27 "is calculated, and the virtual reference marker 30" is calculated, and the coordinates of the image point P 'of the selected area 27' are scaled using the calculated position difference Δ. It is also necessary to take into account the optical distortion that may occur due to the aerial image 40 resulting from the point symmetry. After the above-described correspondence, for example, the aerial image 40 of the tread element 9 of the newly replaced unloaded step band 10 almost coincides with the virtual space 41 and also with the selected region 27 'and the corresponding comparison region 27 ", since the comparison region 27" is always greater than the corresponding selected region 27' by a boundary value and therefore almost coincides.

In a second step, it can be determined whether the image point P 'of the selected region 27' is still within the corresponding comparison region 27 ".

This comparison is schematically illustrated in fig. 2C. By means of the correspondence, the comparison area 27 ″ and the selection area 27' are superimposed on one another and the maximum deviation can now be determined. In the present example, the aerial image 40 of the footboard element 9 deviates in an impermissible manner from the aerial image of the virtual space 41, which is represented by the angles β and γ. Since the lower edge 27 of the resting steps of the tread elements 9 selected as the selected region 27' has an impermissible angular deviation β, the detection device 20 generates a warning signal by means of the control device 24, which immediately decelerates and stops the revolving belt 10. It can be well seen that some areas of the aerial image 40, for example the lower edges of the side panels 31' of the aerial image 40, protrude from the corresponding comparison areas 31 ". Thus, the lower edge of the side panel 31' can be selected. The more regions 27 ', 31' of the aerial image 40 are selected and compared with univocally or singly corresponding comparison regions 27 ", 31" that are within their envelope but not necessarily identical in their position, the more accurately a deviation of the moving belt 10 can be detected and thus the problems of the prior art.

Fig. 3 shows the footboard element 9 as a segment of a revolving belt 10. Although the tread surface 29 of the tread element 9 is oriented horizontally, it has an inclination, represented by the angle ψ, which is shown exaggerated in FIG. 3. A possible cause of such a deviation from the set direction of movement may be uneven wear on the conveyor chain 11, which results in conveyor chains 11 of different lengths. Deflection of the footrest elements 9 can result in an enlarged gap between the adjacent guardrail base 4 and the side edges 36 of the tread surface 29, thereby not allowing easy gripping of the user's item or limb. In order to detect the degree of skewing, the lateral edges 36 and the transverse edges 37 of the retaining tread surface 29, which are held fixed on the aerial image 40, can be selected and imaged by means of reference points, not shown, corresponding to the respective comparison regions 36 ″ and compared with them.

As can be seen from the example of fig. 3, the side edges 36 and the transverse edges 37 or the selected region of the image with these side edges 36 and transverse edges 37 have not yet exceeded the predetermined boundary of the comparison region 36 ″. However, some parts of the side edges 36 and the transverse edges 37 are already close to the above-mentioned boundary of the comparison area 36 ″. Preferably, the detection device 20 comprises an electronic processing unit 22 with an analysis unit 38. By means of the evaluation unit 38, the position of the faces or edges of the selected area relative to the borders of the comparison area 36 ″ is evaluated and a position reserve ψ or, in the present case, an angle ψ of skew can be determined. From the determined position reserve ψ and/or by analyzing the history of a plurality of previously determined position reserves ψ or angles ψ, the next maintenance appointment can be determined. In this way, newly emerging lesions that may lead to serious consequential lesions can be detected as early as possible and their development monitored.

Starting from the position reserve ψ classified as critical for maintenance by the analysis unit 38, the work steps expected to be performed and the maintenance material expected to be required for maintenance are determined, in the present example the conveyor chain 11 with its chain rollers 17 can be determined. This can also be done automatically if necessary, for example by the evaluation unit 38.

The sagging 28 of the handrail 5 shown in fig. 1 can be monitored in exactly the same way. In this case, the corresponding comparison area is a tubular virtual space whose central longitudinal axis corresponds to the curvature present in the setting up of the escalator 1 in that section of the handrail 5. An excessively strongly stressed handrail 5 protrudes at the upper boundary and has an excessively loosely stressed handrail 5 at the lower boundary of the corresponding comparison region.

As already mentioned, there may also be a position determination device 42 arranged on a fixed part of the escalator or moving walkway. Such a position-determining device detects distinct faces, edges or markings of the footboard elements 9 or of the handrail sections of the revolving belts 5, 10. In fig. 3, a push button switch on one of the guide rails 12 is provided as the position determining means 42. As soon as the axle of the traction roller 13 passes the position determination device 42, it generates a trigger for triggering the image recording device 21 as a function of the detected instantaneous position of the surface, edge or marking relative to the position determination device 42. Thus, an aerial image of the footboard element 9 is produced almost in the same position as the guide rail 12 with respect to the fixing part. In other words, although the aerial image shows the various footboard elements 9, they are all captured almost in exactly the same position in relation to the fixing means surrounding the footboard elements. Therefore, correction of distortion of the aerial image can be omitted if necessary, and comparison with the comparison area can be performed directly after performing position compensation by the reference mark.

Possible failure of the position detection means 42 is no longer a problem, since the reference marks can be made at any time with the necessary correspondence and correction. This considerably increases the availability of the detection device and thus also of the escalator or moving walkway.

Fig. 4 shows a possible embodiment of an envelope volume element 32 suitable for a learning operation. The enveloping element 32 is, for example, a conventional trigger element 9, to which additional components 33, 34, 35 representing boundary values are attached. The enveloping body element 32 is then inserted into the revolving belt 10 and moved to the image recording device 21. The aerial image generated by the image recording device 21 also has the reference mark image 30' described in fig. 2 and can be prepared by the processing unit 22, for example by correcting distortions due to the punctiform image by the image recording device 21. In order to reduce the amount of data and save memory resources, only the envelope of the prepared spatial image may be stored in the data memory 39 as the virtual space 41. The respective areas of the virtual space 41 can then be selected and saved as corresponding comparison areas 27 ", 31".

Although the invention has been described by showing specific embodiments, it is obvious that many other embodiments can be provided with the knowledge of the invention, for example by combining features of the various embodiments and/or exchanging functional units of the various embodiments. For example, the laser scanner itself can also be a position determination device, for example by continuously monitoring a specific position of a room, for example whether a clearly identifiable distinct body part of an escalator step is located there. The shooting time can also be triggered by the armrest, but optionally a marking is provided as a distinct body part for triggering the trigger. For the sake of overview, the exemplary embodiments shown in fig. 1 to 4 substantially omit illustration of signal transmission means, power lines, etc. However, these are not necessarily few, so that an escalator with a monitoring device according to the invention can be used without problems. Accordingly, a suitably configured escalator is included within the scope of the present claims.

Finally, it should be noted that terms such as "having," "including," and the like do not exclude other elements or steps, and that terms such as "a" or "an" do not exclude a plurality. Reference signs in the claims shall not be construed as limiting.

Claims (14)

1. Method for detecting and monitoring the mechanical state of an escalator (1) or moving walkway having at least one revolving belt (5, 10) and at least one detection device (20), wherein at least the following method steps are carried out by the detection device (20):

generating at least one aerial image (40) of at least one segment of the revolving belt (5, 10),

selecting at least one region (27 ', 31') of the aerial image (40),

comparing the selected region (27 ', 31 ') with at least one comparison region (27 ', 31 '), wherein the comparison region (27 ', 31 ') is defined by three-dimensional coordinates (x ', y ', z ') and represents a virtual space (41) which can unambiguously correspond to the selected region (27 ', 31 '), and

when the selected area (27 ', 31') differs from the comparison area (27 ', 31') beyond a predetermined boundary, an alarm signal is generated,

characterized in that the correspondence of the comparison zone (27 ', 31') to the selected zone (27 ', 31') is realized by means of a reference mark (30 ') corresponding to a fixed part (12) of the escalator (1) or moving walkway, and that the reference mark (30' ) can be identified both in the aerial image (40) and in the respective comparison zone (27 ', 31').

2. A method as claimed in claim 1, wherein a section of the handrail (5) or at least one distinct face or distinct edge (27, 31) of the footboard element (9) is selected as the selected region (27 ', 31') of the revolving belt.

3. Method according to claim 2, wherein the predetermined boundary of the comparison region (27 ", 31") is exceeded when the selected region (27 ', 31') protrudes from the virtual space (41) over at least one location and/or an edge (27) or a face (31) is absent in the selected region (27 ', 31') and/or the edge or face of the selected region (27 ', 31') is arranged non-parallel to the corresponding edge or face of the virtual space (41) in a manner that exceeds the predetermined angular tolerance boundary.

4. A method as claimed in claim 2 or 3, wherein a segmented series of aerial images (40) of the revolving belt (5, 10) is detected and by comparing the distances of the faces and edges which are fixedly maintained on the images (40) with at least one reference mark image (30 '), an aerial image (40) which best matches the corresponding comparison region (27 ", 31") and its virtual reference mark (30 ") is selected and at least one selected region (27 ', 31 ') of the aerial image (40) is compared with the comparison region (27", 31 ").

5. A method as claimed in any one of claims 1 to 3, wherein there is a position determination device (42) arranged on a stationary part (12) of the escalator (1) or moving walkway, which position determination device detects a distinct face, edge (27) or marking of the footboard elements (9) or handrail sections of the revolving belt (5, 10) and generates a trigger for triggering the image recording device (21) of the detection device (20) as a function of the detected instantaneous position of the face, edge (27, 31) or marking relative to the position determination device (42).

6. Method according to one of claims 1 to 3, wherein the position of the faces or edges of the selected region (27 ', 31') relative to the boundaries of the comparison region (27 ", 31") is analyzed by means of an analysis unit (38) and a position reserve (ψ) is determined and the next maintenance booking time is determined on the basis of the determined position reserve (ψ) and/or by analyzing a history of a plurality of previously determined, stored position reserves (ψ).

7. Method according to claim 6, wherein the work steps to be performed are anticipated and the maintenance materials required for maintenance are anticipated are determined starting from the position reserves (ψ) classified as critical for maintenance by the analysis unit (38).

8. Method according to one of claims 1 to 3, wherein, for generating and storing the comparison regions (27 ", 31"), a learning run is carried out with an envelope element (32) representing the maximum permissible deviation and the spatial image (40) thereof is stored in a data memory (39).

9. A method as claimed in one of claims 1 to 3, wherein the learning travel is carried out with a revolving belt (5, 10) provided for the operation and a segmented aerial image (40) of the revolving belt (5, 10) is generated and, on the basis of the aerial image (40), the comparison regions (27 ", 31") are generated by adding boundary values in the form of three-dimensional coordinates to the distinct edges and faces of the aerial image (40).

10. Method according to one of claims 1 to 3, wherein, for checking the function of the detection device (20), a test run is carried out with at least one test element, which is set in such a way that: so that the test element protrudes from the comparison region (27 ', 31') in at least one region.

11. Escalator (1) or moving walk with revolving belts (5, 10) and at least one detection device (20) for detecting and monitoring the mechanical state of the escalator (1) or moving walk, wherein the detection device (20) comprises at least one image recording device (21) by means of which a spatial image (40) can be generated, and by means of which the state of the revolving belts (5, 10) and/or the arrangement of the sections of the revolving belts (5, 10) relative to the fixed parts (12) of the escalator (1) or moving walk can be detected by means of the detection device (20) in such a way that: at least one spatial image (40) of a segment of the revolving belt (5, 10) is generated, distinct faces or edges (27 ', 31') of the segment captured on the image (40) can be selected by a processing unit (22) of the detection device (20) and can be compared with three-dimensional comparison regions (27 ", 31") stored in a data memory (39), characterized in that,

the comparison region (27 ', 31 ') can correspond to the selected region (27 ', 31 ') by means of a reference mark (30 ' ), the reference mark (30 ' ) corresponding to a fixed part (12) of the escalator (1) or moving walkway, and the reference mark (30 ' ) can be identified both in the aerial image (40) and in the respective comparison region (27 ', 31 ').

12. Escalator (1) or moving walk according to claim 11, wherein the escalator or moving walk has a position-determining device (42) arranged on a stationary part (12) of the escalator (1) or moving walk, by means of which a distinct face, edge (27, 31) or marking of the footboard elements (9) or handrail sections of the revolving belt (5, 10) can be detected and by means of which a trigger for triggering the image capture device (21) can be generated as a function of the detected instantaneous position of the face, edge (27, 31) or marking relative to the position-determining device (42).

13. Escalator or moving walk according to claim 11 or 12, wherein the detection device (20) is arranged between a forward part (14) of the revolving belt (5, 10) and a return part of the revolving belt (5, 10).

14. Escalator or moving walk according to claim 11 or 12, wherein the image recording device (21) is provided with a transparent protective cover (23) and the detection device (20) has a cleaning device (18) by means of which at least one facet of the transparent protective cover (23) is periodically cleaned.