Method for measuring the braking distance of an escalator or a moving walkway

Abstract

The invention relates to a method for measuring the braking distance (LB) and to a braking distance measuring device (30) for carrying out the method on an escalator (1) or a moving walkway. The braking distance measuring device (30) has at least one trigger device (45) which can be connected to the controller (14) of the escalator (1) or the moving walkway, an optically detectable linear measuring scale (31), an optical sensor (35), and an acoustic sensor (36). In order to allow a more precise measurement of the braking distance (LB), a braking process is optically and acoustically recorded as an image sequence (60) with a graphically displayed audio track (65). The start point (68) and the end position (69) of braking operation noises (51) recorded on the audio track (65) can be precisely assigned to the images (62, 63) of the image sequence (60), and the braking distance (LB) is ascertained from the determined images (62, 63) by comparing the different positions of a marking (53) with the measuring scale (31).

Description

[0001] METHOD FOR MEASURING THE BRAKING DISTANCE OF AN ESCALATOR OR MOVING WALK

[0002] The invention relates to a method for measuring the braking distance of an escalator or a moving walkway, a braking distance measuring device for carrying out this method, and an escalator or a moving walkway with such a braking distance measuring device.

[0003] Escalators and moving walkways are used to transport people and are used in department stores, shopping malls, train stations, airports, and other applications. They feature a conveyor belt that is arranged in a rotating manner within the escalator or moving walkway and can be driven by a drive motor. Because these systems transport people, they are subject to stringent safety requirements, such as those defined in the European standard EN 115-1 or the US standard ASME A17.1 / CSA B44.

[0004] One of these safety regulations concerns the permissible length of the conveyor belt's braking distance. This braking distance inevitably occurs due to the inertia of the moving parts after the drive motor is disconnected from the power supply and a service brake or safety brake (hereinafter referred to as the unspecified brake) of the escalator or moving walk is activated. Most authorities require operators or companies entrusted with the maintenance of these systems to periodically check the braking distance and to service the brake if the braking performance does not meet the applicable standards. To prevent falls by users, the brake must not be applied too tightly. Therefore, the standards also specify a maximum permissible deceleration during braking. For example, ENI 15-1 specifies this for escalators and moving walks at a given nominal speed of 0.75m / s (operating speed) a standard braking distance of the conveyor belt in the range between 0.4m and 1.5m, with the maximum permissible deceleration of 1m / s. 2 must not be exceeded.

[0005] To measure the standard braking distance of a conveyor belt, JP2008265971A proposes a braking distance measuring device and a method for performing this measurement. A linear measuring scale is attached to the conveyor belt, and an optical sensor is temporarily attached to a fixed part of the escalator or moving walkway and connected to the escalator's control system. The conveyor belt is then brought up to operating speed. As soon as the optical sensor detects the leading end of the measuring scale, a stop signal is sent to the control system, and the conveyor belt is decelerated by the brake. The distance traveled by the optical sensor on the measuring scale corresponds to the standard braking distance. This measuring method therefore precisely complies with the ENI 15-1 standard, which stipulates that the braking distance must be measured from the moment the stop signal appears until the conveyor belt comes to a standstill.Furthermore, the standard recommends keeping the standard braking distance as close to the lower limit of the range as possible (in the example 0.4 m).

[0006] The braking distance measurement method described above has the disadvantage that it also records periods without braking torque, such as the reaction times of the optical sensor, the controller, and the electromechanical switch (contactor or relay) controlled by the controller, as well as the reaction time of the brake from the interruption of the ventilation current until the braking torque begins to take effect. The braking distance measurement method described therefore does not provide measurement results that reflect the actual braking behavior of the brake (braking distance while the braking torque is applied).

[0007] The object of the present invention is to provide a braking distance measuring method which provides more precise measurement results with regard to the actual braking behavior of the brake.

[0008] This task is solved by the following method for measuring the braking distance of an escalator or a moving walkway and by a braking distance measuring device for carrying out this method.

[0009] The escalator or moving walkway in which such a measurement can be performed comprises a conveyor belt, at least one drive motor for driving the conveyor belt, a brake for decelerating the conveyor belt, and a controller. The drive motor and the brake can be controlled by the controller. The method for measuring the braking distance can be used for all known brake types of escalators and moving walkways. To carry out the method, a braking distance measuring device is arranged in the area of ​​the conveyor belt. This device comprises at least one triggering device connectable to the controller, an optically detectable, linear measuring scale, and an optical sensor.

[0010] The braking distance measurement procedure comprises several steps that can be performed in the following order. However, this order is not mandatory; where appropriate, certain steps can be performed before or after other steps, or additional steps, as described in the following paragraphs, can be inserted between these steps.

[0011] In one process step, the linear measuring scale is arranged in the escalator or moving walkway in such a way that, as a result of the movement of the conveyor belt, it exhibits a relative movement sequence to a marking. This relative movement sequence can be captured by the optical sensor, for example, as an image sequence. As explained below, there are various ways to arrange a measuring scale and define or arrange a marking.

[0012] In a further process step, the conveyor belt is brought up to a specified speed. The specified speed usually corresponds to the transport speed in normal operation, which is usually referred to as the nominal speed. The specified speed can also be faster or slower than the nominal speed if different operating conditions of the service brake are to be tested. Once the specified speed is reached, a stop signal is sent to the control system via the triggering device. The stop signal can be triggered manually, for example by a manual input into the triggering device. However, it is also possible for the stop signal to be generated automatically by the triggering device; for example, if the specified speed is reached, the stop signal in the triggering device is triggered.

[0013] In a further process step, the relative movement sequence is recorded using the optical sensor, at least from the stop signal until the conveyor belt comes to a complete standstill. Furthermore, the braking distance measuring device includes an acoustic sensor that records the braking noises of the brake synchronously with the optical recording. These braking noises represent the actual braking application in chronological order. Since the relative movement sequence was recorded synchronously, the beginning of the braking noises can be clearly assigned to a specific image of the relative movement sequence recorded as an image sequence. To determine the braking distance, a subsequent image from the recorded image sequence of the movement sequence must be selected, which was clearly recorded at a time when no more braking noises were occurring.If the two images are now compared, the braking distance traveled during the actual use of the brake can be read from the different positions of the marking to the measuring scale.

[0014] The braking distance measured in this way, for example, allows the average deceleration of the brake to be calculated more precisely. It is also possible to record a braking curve (distance / time diagram, where time is defined by the number of frames per second) by evaluating the traveled braking distance step by step from frame to frame, from which the maximum deceleration can be determined. Based on these measurement results, the brake can be adjusted close to the maximum permissible deceleration. This minimizes the actual braking distance without exceeding the specified maximum deceleration value.

[0015] Measuring the braking distance during actual brake application also offers advantages when diagnosing the technical condition of the escalator or moving walkway. For example, the condition of the brake pads and / or their change compared to previous measurements can be assessed more precisely. Furthermore, the time at which the stop signal is triggered can also be recorded, allowing an image from the recorded image sequence to be assigned to it. If the optical recording of the movement sequence begins with the stop signal, it is logically the first image. The reaction time of the braking system until the brake actually applies a braking torque, and the distance traveled in this process, can now be determined by comparing the two recording times of this first image and the image with the start of the braking operation noise.The distance traveled by the marker, referred to as the reaction length, can also be determined using these two images. A reaction time or reaction length that is too long compared to empirical values ​​may indicate that, for example, the contactors mentioned above need to be replaced. As mentioned at the beginning, the ENI 15-1 standard stipulates that the braking distance must be measured from the moment the stop signal is triggered until the conveyor belt comes to a complete standstill. This standard braking distance can be determined by simply adding the reaction length and the braking distance.

[0016] As described above, this evaluation can be performed entirely manually, but this is time-consuming. In a further development of the method, the recording of the relative movement and the recording of the synchronously recorded braking noises are displayed as a graphically represented audio track parallel to each other in an image sequence. This makes it much easier to identify the two or three relevant images of an image sequence described above, since the images do not first have to be assigned based on the chronological sequence of the braking noises by reading the recording times.

[0017] A starting position of the marker relative to the measuring scale is then extracted from the image sequence using a starting point of the braking noise. Furthermore, an end position of the marker relative to the measuring scale is also extracted from the absence of the braking noise. The image containing the end position can also be defined using a fixed end position, at which braking noise is guaranteed to be eliminated, since once the conveyor belt stops, braking noise is eliminated and all subsequent images in the image sequence look exactly the same.

[0018] In a further development of the invention, the start position and end position are determined automatically from the graphically displayed braking noise or the audio track using an image processing program. The image processing program uses known image analysis methods and algorithms known from the electronic processing of video sequences. These analysis algorithms are based, for example, on known image processing techniques that are optimized and applied in self-learning processes using artificial intelligence in neural networks. A common image processing technique for generating information from an image is, for example, the calculation of a histogram, which provides information about the statistical brightness distribution in the image.Such a histogram can, for example, serve as a configuration for further image processing steps or as information for a human user of a software. Other calculable information about an image includes its entropy or average brightness. Based on this information, vector analyses can be carried out to determine how individual prominent points shift relative to one another, and from this, conclusions can be drawn about movement scenarios of the marker relative to the measuring scale. Using the aforementioned methods, for example, an image analysis of the audio track visually displayed in the image sequence can be performed. The image in the image sequence containing the starting point of the braking noise and one of the images in the image sequence in which the absence of the braking noise can be clearly identified can be marked in the image sequence.Of course, an analysis of the noise level of the recorded braking operation noise can also be carried out so that the time of the start and end of braking operation can be determined and the corresponding images from the image sequence can be identified via the temporal assignment.

[0019] In a further automation step of this method, the distance between the start position and the end position is determined by comparing the two marked images in the image sequence. This distance corresponds to the braking distance traveled during the brake application. The different positions of the marking relative to the measuring scale can be read, for example, by optical character recognition (OCR) of numbers printed on the measuring scale and subsequent subtraction.

[0020] In one embodiment of the invention, the triggering device is connected to the controller. The triggering device retrieves operating data of the drive motor from the controller, whereby a stop signal is sent to the controller as soon as the drive motor has reached a speed that corresponds to the specified speed of the conveyor belt. In a further embodiment of the invention, the stop signal can be entered manually into the triggering device, for example by pressing a pushbutton or via a keypad on the triggering device. As soon as the stop signal is entered, it is transmitted directly from the triggering device to the controller. Further commands can be transmitted to the controller via the keypad, which can also be generated on a touch-sensitive screen on the triggering device.For example, the start command can be entered via the keyboard so that the control system sets the conveyor belt in motion. Furthermore, the conveying direction or the direction of movement of the conveyor belt can also be entered via the keyboard. It is also possible for the control system to transmit operating data of the passenger conveyor system, such as the current speed, to the triggering device, which can then be displayed on the screen. The control system can also transmit safety-relevant messages to the triggering device, so that, for example, a refusal of the start command and the underlying cause can be displayed on its screen.

[0021] In summary, the braking distance measuring device for carrying out the method described above has at least one triggering device connectable to the controller, an optically detectable, linear measuring scale, an optical sensor, and an acoustic sensor. The optical sensor, the acoustic sensor, and the triggering device are preferably part of a smartphone or tablet with a software application (computer program). The software application comprises at least program steps that enable synchronous recording of a relative movement of the arranged or defined marking to the measuring scale and of the braking operation noises. The software application can also contain program components by means of which the image processing described above can be carried out. Furthermore, a wired or wireless connection to a control system of an escalator or moving walkway can be temporarily established.

[0022] Preferably, the braking distance measuring device comprises a holder for the smartphone or tablet, which holder can be temporarily arranged on a fixed part of an escalator or moving walkway. This fixed part can be, for example, a balustrade or a balustrade base, or a floor covering of the escalator or moving walkway.

[0023] To ensure high-quality recording of braking noise, at least the linear measuring scale, the optical sensor, and the acoustic sensor of the braking distance measuring device are preferably located in a drive area of ​​the escalator or moving walk. In an escalator, the drive area is typically located in the upper access area, so that the conveyor belt is primarily subjected to tensile forces. Typically, the drive motor, a drive shaft, a gearbox, and the brake are located in the drive area beneath a walkable floor covering. The escalator conveyor belt can be entered or exited via this walkable floor covering. Moving walks are designed in a similar manner.

[0024] As mentioned above, various options are available for arranging the linear measuring scale and, if applicable, the marking. The linear measuring scale preferably has a slat-shaped support with a metric length scale and / or a length scale in inches. The marking can be an existing contour of the escalator or moving walkway, but can also be a temporarily attachable object such as a sticker, a colored dot, etc.

[0025] In a first variant, the marking is arranged or defined on the conveyor belt, and the linear measuring scale is arranged on a fixed part of the escalator or moving walkway. To simplify handling for the person entrusted with the measurement, the marking is preferably defined. In this case, the marking is, for example, a gap between two escalator steps of the escalator's conveyor belt or a gap between two pallets of the moving walkway's conveyor belt. Of course, a marking that can be temporarily applied to the conveyor belt can also be used, such as a line drawn with a waterproof felt-tip pen that extends transversely to the direction of movement of the conveyor belt.

[0026] In a second variant, the measuring scale is arranged on the conveyor belt, and the marking is defined or positioned on a fixed part of the escalator or moving walkway. For example, the marking could be a metal joint between two cladding panels of a balustrade on the escalator or moving walkway. Of course, a marking that can be temporarily applied to the balustrade, such as an arrow-shaped sticker, can also be used.

[0027] Embodiments of the invention are described below with reference to the accompanying drawings, whereby neither the drawings nor the description are to be interpreted as limiting the invention. The figures are merely schematic and not to scale. Identical or equivalent features have the same reference numerals. They show:

[0028] Figure 1: schematic sectional side view of an escalator and its main components;

[0029] Figure 2: a three-dimensional partial view of the drive area shown in Figure 1 with a braking distance measuring device;

[0030] Figure 3: a three-dimensional view of a smartphone with a software application through which the smartphone can be used as a component of the braking distance measuring device;

[0031] Figure 4: an image from an image sequence recorded by an optical sensor of the braking distance measuring device shown in Figure 2;

[0032] Figure 5A: a first image from an image sequence recorded by the braking distance measuring device at the time of input of a stop signal;

[0033] Figure 5B: a second image from the same image sequence at the time of a starting point at which parallel recorded brake operation noises begin; and

[0034] Figure 5C: a third image from the same image sequence at the time of an end position at which parallel recorded braking noises end.

[0035] Figure 1 shows a schematic, sectional side view of an escalator 1 and its most important components. With the help of the escalator 1, people can be transported, for example, between two levels E1, E2 of a building. The escalator 1 has a conveyor belt 26 with a plurality of escalator steps 3, which are arranged one behind the other and can be moved in a direction of movement 6 along a travel path with the help of two conveyor chains 5 (only one visible in Figure 1) that are closed in a ring and arranged parallel to one another. The double arrow in the direction of movement 6 indicates that the escalator 1 can transport users both from level E1 to level E2 and in the opposite direction. Each escalator step 3 is attached to the two conveyor chains 5 between them.To enable the conveyor chains 5 to be moved, the escalator 1 has a drive section 13 in which a drive shaft 17, a gear 16, a drive motor 19, and a brake 18 are arranged. The escalator 1 can have various brake types, for example, the service brake shown in Figure 1, which is typically designed as a shoe brake or band brake. Additionally, the escalator can also have a safety brake, as disclosed, for example, in WO2014 / 009227A1.

[0036] The drive area 13 is usually located on the upper level E2 of the structure, while a tensioning station 7 (shown only schematically) with a deflection shaft 15 is located on the lower level E1. The drive shaft 17 and the deflection shaft 15, as well as other load-bearing components of the escalator 1, are held in a supporting structure 2, usually in the form of a truss structure, which is shown only as an outline in Figure 1 for reasons of clarity. The escalator 1 also has two balustrades 8 (only one visible), each of which has a handrail 4 arranged circumferentially.

[0037] During an upward movement direction 6, the escalator steps 3 are moved in the forward direction from a lower access area 10 of the escalator 1 bordering on the lower level Elan, via a central inclined area 11, to an upper access area 12 bordering on the upper level Elan and then moved back in the opposite direction in the return direction.

[0038] The drive motor 19 and the brake 18 arranged in the drive area 13 are controlled and regulated by a controller 14. The torque or the rotational movement of the motor shaft (covered by the gear) of the drive motor 19 is transmitted to the drive shaft 17 via the gear 16 (shown as an example is a worm gear and a drive chain). Since two conveyor chains 5 are usually present, between which the escalator steps 3 are arranged, the drive shaft 17 must also have two drive sprockets (not shown in detail), over which the conveyor belt 26 is guided in a motion-transmitting manner. All components of the drive area 13 are also housed in the supporting structure 2 and are spanned by a walkable floor cover 9, which is part of the upper access area 12.

[0039] Furthermore, in the drive area 13 of the escalator 1, a braking distance measuring device

[0040] 30 for measuring the braking distance. In the present embodiment, this braking distance measuring device 30 is temporarily installable, meaning it can be installed, used, and removed again as needed. However, a permanent installation of the braking distance measuring device 30 is also conceivable, for example, in a balustrade base 20 of the balustrade 8.

[0041] Figure 2 shows a three-dimensional, enlarged partial view of the drive area 13 designated in Figure 1 with a braking distance measuring device 30 installed there. The braking distance measuring device 30 has a linear measuring scale 31 and a smartphone 32 with an optical sensor 35 and an acoustic sensor 36 (see Figure 3). Furthermore, the braking distance measuring device 30 comprises a holder 33 for the smartphone 32 and fastening means 34 for the linear measuring scale 31. In the present embodiment, the slat-shaped measuring scale 31 is placed with its first end 31A on the floor covering 9 and fixed to the floor covering 9 with the fastening means 34 in the shape of a brick. The linear measuring scale

[0042] 31 is arranged in the drive area 13 with respect to its longitudinal extent parallel to the direction of movement 6. Its second end 31B protrudes beyond a comb plate 27 serving as a transition from the floor covering 9 to the conveyor belt 26 and also protrudes beyond more than two escalator steps 3 of the conveyor belt 26. In the present exemplary embodiment, the holder 33 has a suction cup 37 which is fixed to a cladding plate 21 of the balustrade base 20. The smartphone 32 rests on the holder 33, wherein the holder 33 is arranged on the cladding plate 21 in such a way that the optical sensor 35 of the smartphone 32 can detect both the linear measuring scale 31 and at least two escalator steps 3 of the conveyor belt 26.Since the brake 18 is located below the floor cover, this arrangement also ideally positions the acoustic sensor 36 (see Figure 3) of the smartphone 32 for recording braking operating noises 51 (see Figures 5A to 5C).

[0043] Figure 3 shows a three-dimensional view of a smartphone 32 with a software application 38, through which the smartphone 32 can be used as a component of the braking distance measuring device 30. In addition, Figure 3 schematically illustrates the components drive motor 19, brake 18, and controller 14 of the escalator 1 to illustrate their interactions with the smartphone 32.

[0044] The use of a conventional smartphone 32 is suitable because it has sufficient computing power and storage capacity to store and process the software application 38 and features an optical sensor 35 (symbolically represented as a video camera), an acoustic sensor 36 (symbolically represented as a handheld microphone), and a touch-sensitive screen 39 on which graphic buttons 41, 42, 43, 44 and thus manually operable elements of a triggering device 45 can be generated. Furthermore, the smartphone 32 has a communications module 47 through which a data connection can be established to the escalator controller 14. Since a so-called tablet has the same components and properties, a tablet can also be used instead of the smartphone 32.Of course, generic components intended to be used instead of the smartphone 32 for the braking distance measuring device 30 can also be combined in a device specifically designed and built for the braking distance measuring device 30. It is even possible to arrange the aforementioned components separately from one another in the drive area 13, whereby a communication connection 47 must be established, at least temporarily, between the triggering device 45, the optical sensor 35, the acoustic sensor 36, and, if applicable, the controller 14. The triggering device 45 can be designed as a handheld device with a pushbutton (not shown), for example, to input a stop signal 46.

[0045] The aforementioned software application 38 for the smartphone 32 comprises at least program steps that enable synchronous recording of a relative movement of a marking 53, 54, 55 to the linear measuring scale 31 and the braking operating noise 51 of the brake 18 (see Figure 4). Further explanations of the linear measuring scale 31 and the aforementioned marking 53, 54, 55 can be found further below in the description of Figure 4.

[0046] The software application 38 also has program steps by means of which the required graphic buttons 41, 42, 43, 44 and / or graphic representations 48 of operating data can be generated on the screen 39 following the process sequence. In the present exemplary embodiment, a first button 41 serves to set the escalator 1 (see also Figure 1) in motion with a direction of movement 6 from the lower floor E1 to the upper floor E2. With a second button 42, the escalator 1 can be set in motion with a direction of movement 6 from the upper floor E2 to the lower floor E1.

[0047] In a central area of ​​the screen 39, a graphic representation 48 can be created and displayed through further program steps of the software application 38. The measurement data required for this are transmitted from the controller 14 via the communication module 47 to the smartphone 32 serving as the triggering device 45. The graphic representation 48 of the exemplary embodiment shows the acceleration behavior of the conveyor belt 26 from a standstill Vo to the nominal speed VN. As soon as the nominal speed VN is reached, a stop signal 46 can be entered via a third button 43 of the triggering device 45 and sent to the controller 14 of the escalator 1. When the stop signal 46 is entered, the optical sensor 35 and the acoustic sensor 36 are simultaneously activated in order to record an image sequence 60 and an associated sound track 65 (see Figures 4 and 5A to 5C).

[0048] The stop signal 46 is immediately processed by the controller 14, so that the drive motor 19 is disconnected from a power supply (not shown), and the brake 18 is activated by switching off a ventilation current. As soon as the brake shoes 18' of the brake 18 engage, a loud braking noise 51 is released with a decreasing tendency, and this continues until the conveyor belt 26 (see Figure 1) comes to a standstill. It should be noted at this point that the braking noise 51 of a service brake and a safety brake can differ, particularly when the braking noise 51 fades away. However, what all brake types have in common is that the onset of the braking noise 51 is clearly identifiable on the audio track 65. As soon as the conveyor belt 26 comes to a standstill, tapping a fourth button 44 of the triggering device 45 can initiate an evaluation of the measurement results and a determination of a braking distance LB from the measurement performed.The determination of the braking distance LB is shown below using Figures 5A to 5C.

[0049] Figure 4 shows an image 64 from an image sequence 60 recorded by the optical sensor 35 of the braking distance measuring device 30 shown in Figures 1 and 2. The linear measuring scale 31 arranged above the escalator steps 3 of the conveyor belt 26 is clearly visible. Furthermore, the balustrade base 20 is partially visible, in particular two cladding sheets 22, 23 of the balustrade base 20 as well as the floor cover 9 and the comb plate 27.

[0050] As already mentioned above, the linear measuring scale 31 is arranged in the drive area 13 and a marking 53, 54 is defined or also arranged. In the actual arrangement captured in the image, a gap arranged between two escalator steps serves as a marking 53, which moves relative to the stationary measuring scale 31 when the conveyor belt 26 is running. In other words, the gap is defined as a marking 53. Alternatively, a special marking 54 can also be temporarily applied to the conveyor belt 26, for example the arrow indicated by a broken line, which is preferably applied to one of the escalator steps 3 using a clearly visible color or as a sticker. It should also be noted that in the case of a conveyor belt 26 of a moving walkway, the gap between two pallets can be defined as a marking 53.Due to the very narrow design of pallets, it may be better to provide a temporary marking 54.

[0051] As shown by the dot-dash line, the measuring scale 56 can also be arranged, for example, as a sticker on the conveyor belt 26. In this embodiment, the marking 24, 55 is provided on a fixed part of the escalator 1 or the moving walkway. For example, the marking 24 can be defined as a sheet metal joint between the two cladding panels 22, 23. In this alternative, the marking 55 can also be an arrow-shaped sticker, which can be temporarily affixed to a fixed part of the escalator 1 or the moving walkway.

[0052] The method that can be carried out with the braking distance measuring device 30 described above is explained below with reference to Figures 5A to 5C and with the aid of Figures 2 and 3. Figure 5A shows a first image 61 from an image sequence 60 recorded by the braking distance measuring device 30 at the time of input 67 of a stop signal 46. Figure 5B shows a second image 62 from the same image sequence 60 at the time of a starting point 68 at which parallel-recorded braking noises 51 begin. Figure 5C shows a third image 63 from the same image sequence 60 at the time of an end position 69 at which the parallel-recorded braking noise 51 ends.

[0053] The method for measuring the braking distance LB of an escalator 1 or a moving walk comprises, on the one hand, preparatory steps and, on the other hand, measurement and evaluation steps. The preparatory steps include arranging a braking distance measuring device 30 in the drive area 13 above the conveyor belt 26. Possible embodiments of this have already been described above with reference to Figures 2 and 4. Furthermore, the triggering device 45 of the braking distance measuring device 30 is connected to the control system 14 of the escalator 1 in a signal-transmitting manner.

[0054] The measurement steps include the process steps required to generate image sequences 60 and an associated audio track 65 with the braking operation noises 51. Thus, by a manual input on the triggering device 45, the conveyor belt 26 is brought to a predetermined speed Vv, for example, the nominal speed VN. After the predetermined speed Vv is reached, a stop signal 46 is sent to the controller 14 by means of the triggering device 45. It is also possible for the triggering device 45 to receive operating data from the drive motor 19 from the controller 14 and to automatically send a stop signal 46 to the controller 14 as soon as the drive motor 19 has reached a speed that corresponds to the predetermined speed Vv of the conveyor belt 26.Upon input of the stop signal 46, the optical sensor 35 begins recording the relative movement sequence between the marking 53 and the linear measuring scale 31, at least from the stop signal 46 until the conveyor belt 26 comes to a standstill Vo. Synchronously with the optical recording, the audio track 65 with the braking operating noises 51 of the brake 18 is recorded by the acoustic sensor 36 of the braking distance measuring device 30.

[0055] As shown in Figures 5A to 5C, for simpler and clearer evaluation, the recording of the relative movement between the marking 53 and the linear measuring scale 31 and the recording of the synchronously recorded sound track 65 are combined parallel to each other in an image sequence 60.

[0056] The first recorded image 61 of the image sequence 60 can be assigned to the time of input 67 of the stop signal 46. The sound track 65 is not simply a horizontal line, but has a noise level that represents the normal operating noise of the escalator 1 at the rated speed VN. The signal input position 81, shown with a dashed line, at the time of the stop signal 46 can be read and noted on the first image 61 from the position of the marker 53 to the measuring scale 31.

[0057] If, in the present embodiment of Figures 5A to 5C, the sound track 65 is moved with the finger 74 according to the arrow 70 against the fixed mark 75 generated on the screen 39 by the software application 38 (see Figure 3), the subsequent images of the image sequence 60 are displayed on the screen 39 in chronological order.

[0058] As Figures 5A and 5B show, the audio track 65 exhibits a sudden increase in the noise level, which then continuously decreases. This section of the audio track 65 exhibits the braking noise 51. The second image 62 shows the position of the marker 53 relative to the linear measuring scale 31 at a starting point 68 at which the parallel recorded braking noise 51 begins. The second image 62 is displayed when the sudden increase in the noise level coincides with the fixed mark 75. Again, the position of the marker 53 can be read from the measuring scale 31 and recorded as the starting position 82 of the braking noise 51.The distance traveled by the marking 53 between the signal input position 81 and the start position 82 is the reaction length LR, which arises because the control 14 and the components involved in a brake application, such as contactors for interrupting the ventilation current (not shown) and the brake 18 itself, have a certain reaction time.

[0059] The third image 63 of the image sequence 60 shows the position of the marker 53 relative to the linear measuring scale 31 at the time of an end position 69, at which the parallel recorded braking noises 51 end on the audio track 65 and thus the conveyor belt 26 is stationary. The third image 63 is displayed when the noise level of the audio track 65 has dropped to its lowest level. The audio track 65 only has a background noise. Since the conveyor belt 26 is stationary from this point onwards, all subsequent images in the image sequence 60 look exactly the same. Instead of precisely determining the end of the braking noise 51, it is preferable to select an image 63 which reliably reproduces a static state of the conveyor belt 26. This is the case when two images at the end of the image sequence 60 that are separated in time have an identical position of the marker 53 relative to the measuring scale 31.Again, the position of the mark 53 can be read from the measuring scale 31 and recorded as the end position 83.

[0060] As Figures 5B and 5C show, the marker 53 defined in Figure 5A disappears when the sound track 65 is moved further with the finger 74 at the lower edge of the image, which is why in Figure 5B the subsequent gap between two escalator steps 3 is alternatively defined as marker 53'. Accordingly, a new starting position 82' is also alternatively read and recorded on the measuring scale 31.

[0061] The distance traveled by the marker 53' between the start position 82' and the end position 83 is the actual braking distance LB during the application of brake 18. As mentioned above, the ENI 15-1 standard stipulates that the braking distance must be measured from the input 67, or from the occurrence of the stop signal 46, until the conveyor belt 26 comes to a complete standstill. This standard braking distance can be determined by simply adding the reaction length Ln and the braking distance LB.The previously described manual evaluation of the image sequence 60 can also be carried out automatically using an image processing program by performing an image analysis of the course of the recorded braking noises 51 visually displayed in the image sequence 60 and marking in the image sequence 60 the image of the image sequence 60 containing the starting point 68 of the braking noise 51 and one of the images of the image sequence 60 in which the absence of the braking noise 51 is clearly recognizable. In the automated process, the braking distance LB between the starting position 82 and the end position 83 is also determined by comparing the two marked images of the image sequence 60. The different positions of the marking 53 relative to the measuring scale 31 are read out, and the braking distance LB is determined by calculating the difference.

[0062] Although escalators are shown in Figures 1 and 2, it is obvious that the braking distance measuring device 30 and the associated method can also be used for moving walks.

[0063] Finally, it should be noted that terms such as "having," "comprising," etc., do not exclude other elements or steps, and terms such as "a" or "an" do not exclude a plurality. Furthermore, it should be noted that features or steps described with reference to one of the above embodiments may also be used in combination with other features or steps of other embodiments described above. Reference signs in the claims are not to be considered as limitations.

Claims

Patent claims 1. A method for measuring the braking distance (LB) of an escalator (1) or a moving walkway, wherein the escalator (1) or the moving walkway comprises a conveyor belt (26), at least one drive motor (19) for driving the conveyor belt (26), a brake (18) for braking the conveyor belt (26), and a control unit (14), wherein the drive motor (19) and the brake (18) are controllable by the control unit (14), and wherein a braking distance measuring device (30) is arranged at least temporarily in the area of ​​the conveyor belt (26), which comprises at least one triggering device (45) connectable to the control unit (14), an optically detectable linear measuring scale (31), and an optical sensor (35), characterized in that • that the linear measuring scale (31) is arranged on the escalator (1) or on the moving walkway in such a way that its relative movement sequence to a marking (24, 53, 54, 55) as a result of a movement of the conveyor belt (26) can be detected by the optical sensor (35); • that the conveyor belt (26) is brought to a predetermined speed (Vv); • that after reaching the specified speed (Vv) a stop signal (46) is sent to the control unit (14) by means of the triggering device (45); • that the recording of the relative motion sequence is carried out at least from the stop signal (46) until the conveyor belt (26) has come to a complete standstill by means of the optical sensor (35); and • that the braking distance measuring device (30) also includes an acoustic sensor (36) which records the braking operating noises (51) of the brake (18) synchronously with the optical recording.

2. The method of claim 1, wherein the recording of the relative motion as well as the recording of the data recorded synchronously with the relative motion Brake operating noises (51) are presented as a graphically represented sound track (65), parallel to each other in a picture sequence (60).

3. Method according to claim 2, wherein a starting position (82, 82') of the marking (24, 53, 54, 55) relative to the measuring scale (31) is extracted from the image sequence (60) by means of a starting point (68) of the brake operating noise (51), and an end position (83) of the marking (24, 53, 54, 55) relative to the measuring scale (31) is extracted from the cessation of the brake operating noise (51).

4. Method according to claim 3, wherein the determination of the start position (82, 82') and the end position (83) is carried out by means of an image processing program by performing an image analysis of the optically represented course of the recorded brake operating noises (51) in the image sequence (60) and marking the image (62) of the image sequence (60) containing the start point (68) of the brake operating noise (51) and one of the images of the image sequence (60) in which the cessation of the brake operating noise (51) is clearly recognizable in the image sequence (60).

5. Method according to claim 4, wherein the determination of the braking distance (LB) between the start position (82, 82') and the end position (83) is carried out by means of an image comparison of the two marked images (62, 63) of the image sequence (60), by reading out the different positions of the marking (24, 53, 54, 55) to the measuring scale (31) and determining the braking distance (LB) by calculating the difference.

6. Method according to any one of claims 1 to 5, wherein the triggering device (45) is connected to the control unit (14) and receives operating data of the drive motor (19) from it, wherein a stop signal (46) is sent to the control unit (14) as soon as the drive motor (19) has reached a rotational speed which corresponds to the predetermined speed (Vv) of the conveyor belt (26).

7. Method according to one of claims 1 to 5, wherein a stop signal (46) can be manually entered into the triggering device (45), which stop signal (46) is transmitted directly from the triggering device (45) to the control (14).

8. Braking distance measuring device (30) for carrying out the method on an escalator (1) or a moving walkway according to one of claims 1 to 7, characterized in that the braking distance measuring device (30) has at least one triggering device (45) connectable to the control unit (14), an optically detectable, linear The measuring scale (31), an optical sensor (35) and an acoustic sensor (36) are included.

9. Braking distance measuring device (30) according to claim 8, wherein the optical sensor (35), the acoustic sensor (36) and the triggering device (45) are part of a smartphone (32) or tablets with a software application (38), wherein the software application (38) includes at least program steps which enable a synchronous recording of a relative movement of the marker (24, 53, 54, 55) to the measuring scale (31) and the brake operating noises (51).

10. Braking distance measuring device (30) according to claim 9, wherein this device has a holder (33) for the smartphone (32) or tablet includes a holder (33) that can be temporarily attached to a fixed part of an escalator (1) or moving walkway.

11. Escalator (1) or moving walkway with a braking measuring device (30) according to one of claims 8 to 10, characterized in that at least the linear measuring scale (31), the optical sensor (35) and the acoustic sensor (36) of the braking distance measuring device (30) are arranged in a drive area (13) of the escalator (1) or the moving walkway.

12. Escalator (1) or moving walkway according to claim 11, wherein the marking (53, 54) is arranged or defined on the conveyor belt (26), and the measuring scale (31) is arranged on a fixed part of the escalator (1) or moving walkway.

13. Escalator (1) or moving walkway according to claim 12, wherein the marking (53) is a gap between two escalator steps (3) of the conveyor belt (26) of the escalator (1), or a gap between two pallets of the conveyor belt (26) of the moving walkway, or a marking (54) that can be temporarily attached to the conveyor belt (26).

14. Escalator (1) or moving walkway according to claim 11, wherein the measuring scale (56) is arranged on the conveyor belt (26), and the marking (24, 55) is arranged on a fixed part of the escalator (1) or moving walkway.

15. Escalator (1) or moving walkway according to claim 14, wherein the marking (55) is an arrow-shaped sticker which can be temporarily attached to a fixed part of the escalator (1) or moving walkway.

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