JP2013147339A - Elevator system and elevator inspection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly inspect a sensor for detection of opening and closing of an elevator door.SOLUTION: A plurality of light projectors 311 are provided to one 15L of doors, and a plurality of light receivers 321 forming pairs with the opposite light projectors are provided to the other 15R of the doors. A door control device 210 determines the presence of abnormal conditions on the basis of a light receiving amount of the light receiver for each of the plurality of pairs, forcibly opens and closes the doors after the passage of a predetermined time after the abnormal conditions are detected, selects the pair detecting the abnormal condition as an inspection object pair if the abnormal conditions continue even when the doors are forcibly opened and closed, and inspects the conditions of the inspection target pair by using an inspection target light projector and an inspection target light receiver constituting the inspection target pair and at least one of another light projector positioned within a predetermined range of the inspection target light projector or another light receiver positioned within a predetermined range of the inspection target light receiver, in a predetermined combination.

Description

  The present invention relates to an elevator system and an elevator inspection method.

  An obstacle detection sensor such as a photoelectric switch is provided on the door of the elevator car, and the door is opened and closed so that passengers or luggage are not pinched by the door. In the first prior art, the sensor is operated while moving the door in the opening and closing direction, the distance when the amount of light received by the light receiver reaches a predetermined threshold is obtained, and the aging of the sensor is based on the change in the distance. (Patent Document 1). In the second prior art, it is determined that a sensor that outputs information different from other sensors among a plurality of sensors is malfunctioning (Patent Document 2).

JP 2011-26013 A JP 2006-188334 A

  In the first prior art, the amount of light received by each sensor is compared with a threshold value. The amount of light received by the light receiver changes in inverse proportion to the square of the distance between the projector and the light receiver. Therefore, since the change in the amount of received light is too large at the normal door opening / closing speed, the detection accuracy decreases. Therefore, at the time of inspection, it is necessary to gradually open and close the door at a speed slower than the normal door opening and closing speed, and inspection time is required.

  In the second prior art, it is only determined which sensor is in failure according to a so-called majority vote, and no clue for estimating the failure content is obtained.

  An object of the present invention is to provide an elevator system and an elevator inspection method capable of inspecting a pair of a projector and a light receiver relatively easily. Another object of the present invention is that the inspection object pair of the projector and the light receiver can be inspected relatively easily during the normal operation of the elevator, and the inspection result is output to the outside for use in analysis. It is an object of the present invention to provide an elevator system and an elevator inspection method.

  In order to solve the above-described problems, an elevator system according to the present invention is an elevator system that controls an elevator that operates between a plurality of floors, and opens and closes a car body that reciprocates up and down between the floors, and an entrance of the car body. A pair of doors, a plurality of projectors provided at one of the doors with a predetermined spacing, and a plurality of projectors provided with a predetermined spacing at the other of the doors so as to form a pair with a corresponding projector among the plurality of projectors. A door control device that determines the presence or absence of an abnormal state based on the amount of light received by the light receiver for each of a plurality of pairs, and controls the opening and closing of the door. A pair in which a state is detected and an inspection target pair that is determined to satisfy a predetermined inspection condition that is set in advance is subjected to a predetermined inspection. And at least one of another light projector located within a predetermined range of the inspection target light projector and another light receiver located within a predetermined range of the inspection light receiver Are used in a predetermined combination to inspect the state of the pair to be inspected.

It is a whole block diagram of an elevator system. It is explanatory drawing which shows the structure of a door sensor, and the structure of a door control apparatus. The flowchart which shows the whole operation | movement which concerns on a self-diagnosis. Explanatory drawing which shows the method for detecting the adhesion etc. of the dirt by the side of a light receiver. Explanatory drawing which shows the method for detecting the light quantity fall etc. of a light projector. The flowchart which shows the self-diagnosis process at the time of the door opening of the light receiver side. The flowchart which shows the self-diagnosis process at the time of the door closing of the light receiver side. The flowchart which shows the self-diagnosis process at the time of the door opening by the side of a projector. The flowchart which shows the self-diagnosis process at the time of the door closing by the side of a projector. The screen block diagram which shows the example of the self-diagnosis result screen provided to a maintenance worker.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, as will be described in detail below, the state of the sensor provided in the door of the elevator car is automatically inspected, and the inspection result is output to the outside.

  FIG. 1 is an explanatory diagram showing the overall configuration of the elevator system. The elevator system includes, for example, an elevator device 10, an elevator control device 20 for controlling the elevator device 10, and a control center 50 that remotely monitors the elevator control device 20. For convenience, FIG. 1 shows one elevator apparatus 10 and one elevator control apparatus 20, but one elevator control apparatus 20 can control a plurality of elevator apparatuses 10, and one control center 50 has a plurality of elevator controls. The device 20 can be managed.

  The elevator apparatus 10 includes an elevator car (hereinafter referred to as a car) 11 that moves up and down between a plurality of landings 17, a drive apparatus 12 that moves the car 11 up and down via a rope 13, and opens and closes a door 15, and the car 11. And a weight 14 for balancing the weight of. Further, the car 11 is provided with a weight sensor 16 for detecting the weight.

  The elevator control device 20 includes, for example, an elevator operation control device 200 for controlling the operation of the elevator device 10 and a door control device 210 for controlling opening and closing of the door 15 and the like. The elevator operation control device 200 manages the operation of the car 11 based on the calls generated in the car 15 and the calls generated at the landing 17. Details of the door control device 210 will be described later.

  The control center 50 is connected to the plurality of elevator control devices 20 via the communication network CN so as to be capable of bidirectional communication. The control center 50 is packed with monitoring personnel 24 hours a day, 365 days a year, and remotely monitors the state of each elevator apparatus 10.

  The maintenance information terminal 60 is connected to the control center 50 via the communication network CN so as to be capable of bidirectional communication. The maintenance information terminal 60 is an information terminal possessed by a maintenance worker, and is configured, for example, as a personal computer or a portable information terminal (including a mobile phone). On the maintenance information terminal 60, a screen G10 (FIG. 10) including a self-diagnosis result to be described later is transmitted from the control center 50 and displayed.

  FIG. 2 is an explanatory diagram showing the configuration of the door sensor for confirming the safety of the door 15 and the configuration of the door control device 200. The door 15 includes a pair of left and right door main bodies 15L and 15R, and a plurality of door sensors provided at opening and closing ends of the door main bodies 15L and 15R.

  A plurality of door sensors are provided at predetermined distances in the longitudinal direction of the door main bodies 15L and 15R. Each door sensor includes a pair of light projectors 311 and light receivers 321 facing each other. That is, the door sensor is configured by the pair of light projectors 311 and light receivers 321 facing each other. The plurality of projectors 311 constitute a projector array 310. The plurality of light receivers 321 constitute a light receiver array 320.

  The door control device 210 includes, for example, a sensor control unit 211, a door control unit 212, a received light amount detection unit 213, a comparison determination unit 214, and a storage unit 215. The sensor control unit 211 controls the operation of the door sensor (a pair of the projector 311 and the light receiver 321), and outputs an obstacle detection signal from the door sensor to the door control unit 212. The door control unit 212 opens and closes the door 15 by driving the door driving device 150 in accordance with an opening / closing instruction from an opening / closing button in the car 11 and a button (both not shown) provided on the landing 17.

  The received light amount detector 213 detects the received light amount at each light receiver 321 based on the value of the detection signal received from each light receiver 321. The comparison determination unit 214 determines whether or not the light from the light projector 311 is received by the light receiver 321 by comparing the amount of light received by the light receiver 321 with a predetermined light reception determination threshold value set in advance. When light is received, it is determined as a light receiving state, and when it is not received, it is determined as a light blocking state. If it is determined that the light is blocked, the sensor control unit 211 determines that an obstacle has been detected.

  The storage unit 215 is used by the sensor control unit 211. The storage unit 215 temporarily stores information (such as the amount of received light) used in the self-diagnosis process.

  The normal operation of the door sensor will be described first. In accordance with a light projection command from the sensor control unit 211, the light projector 311 outputs a light beam (for example, infrared light) toward the opposing light receiver 321. The light receiver 321 that forms a pair with the projector 311 outputs an electric signal corresponding to the intensity of the light received from the projector 311 to the received light amount detection unit 213.

  As described above, the comparison / determination unit 214 compares the amount of received light with a predetermined threshold value to determine whether the light reception state or the light-shielding state, and outputs the determination result to the sensor control unit 211. The sensor control unit 211 determines that an obstacle is present based on the determination result that the light is blocked, and outputs an obstacle detection signal to the door control unit 212. The sensor control unit 211 adjusts the output luminous intensity of the projector 311 and adjusts the light reception gain of the received light amount detection unit 213 so that the determination result of the comparison determination unit 214 is stabilized.

  An outline of the self-diagnosis process will be described. The door control device 210 stores a value of a detection signal indicating the amount of light received by the pair of light receivers 321 that detected the obstacle in the storage unit 215. Next, in the door open state, the door control device 210 enables other light projectors or light receivers that exist in the vicinity of the pair to be inspected, detects the amount of received light according to a predetermined combination, and compares and determines The determination result (whether the light receiving state or the light shielding state) by the unit 214 is stored in the storage unit 215.

  Thereafter, the door control device 210 closes the door 15 by temporarily disabling the pair of the light projector 311 and the light receiver 321 that detect the obstacle. The door control device 210 enables other light projectors or light receivers that exist in the vicinity of the pair to be inspected in the door-closed state, detects the amount of received light according to a predetermined combination, and the comparison determination unit 214 The determination result is stored in the storage unit 215. The sensor control unit 211 of the door control device 210 performs a self-diagnosis process based on the determination result stored in the storage unit 215. The result of the self-diagnosis process is sent to the control center 50.

  FIG. 3 is a flowchart showing the entire operation related to the self-diagnosis. The door control device 210 determines whether a predetermined diagnostic condition set in advance is satisfied (S10). Here, as the predetermined diagnosis condition, for example, even if the door sensor forcibly opens and closes after the door sensor detects the presence of the obstacle for a predetermined time or longer, the door sensor continues to detect the presence of the obstacle. It is that you are.

  When a predetermined diagnosis condition is satisfied, the door sensor that continues to detect an obstacle is selected as a door sensor to be inspected and is a target of self-diagnosis processing (S11). Even though it is determined that there is no obstacle due to the forced opening / closing operation of the door 15, the obstacle is still detected, so that it becomes a target of the self-diagnosis process.

  The result of the self-diagnosis process is transmitted from the elevator control device 20 to the control center 50 via the communication network CN (S12).

  When the control center 50 receives the result of the self-diagnosis process from the elevator control device 20 (S13), the result of the self-diagnosis process is transmitted to the maintenance worker's terminal 60 and displayed as necessary (S14).

  The self-diagnosis processing method will be described with reference to FIGS. FIG. 4 shows a method for detecting dirt 400 adhering to the surface of the light receiver 321. 4A shows an inspection in a state where the door 15 is open, and FIG. 4B shows an inspection in a state where the door 15 is closed.

  A case where the dirt 400 is attached in front of the light receiver 321C will be described as an example. The dirt 400 is not transparent to the light beam from the projector 311 and has an optical property of absorbing at least a part thereof. The light receiver 321C that is at least partially covered with the dirt 400 is the inspection target light receiver, the light projector 311C that is paired with the inspection target light receiver 321C, the inspection target light projector, the inspection target light projector, and the inspection target light receiver. These pairs are called inspection target pairs.

  As shown to Fig.4 (a), in the door open state, the light projector 311D adjacent to the test object light projector 311C is made effective, and the light ray L11 is output. The light beam (optical axis) L11 travels toward the light receiver side, but is blocked or attenuated by the dirt 400. Therefore, the amount of light received by the inspection target light receiver 321C is smaller than the threshold value, and is determined to be in a light shielding state.

  Therefore, the projector 311E further adjacent to the projector 311D is enabled to output the light beam L12. Here, it is assumed that the light beam L12 is incident on the inspection target light receiver 321C without being blocked by the dirt 400.

  Since neither the light beam L10 from the inspection target projector 311C nor the light beam L11 from the light projector 311D adjacent to the inspection target projector 311C is received by the inspection target light receiver 321C, it can be estimated that this is not a problem on the projector side. Further, since the light beam L12 from the projector 311E further adjacent to the projector 311D is received by the inspection target light receiver 321C, it can be estimated that it is not a problem of the inspection target light receiver 321C. Therefore, it can be determined whether dirt or something is attached to the front side of the inspection target light receiver 321C.

  As shown in FIG. 4B, in the door-closed state, the light projector 311D adjacent to the inspection target light projector 311C is enabled and the light beam L11 is output. When the door is closed, the distance between the projector and the light receiver is reduced, and the incident angle of the light beam changes from that when the door is opened. Therefore, the light beam L12 from the projector 311D is received by the inspection target light receiver 321C without being blocked by the dirt 400.

  In the door open state (door open end) shown in FIG. 4A, the inspection target light receiver 321C cannot receive the light beam L11 from the light projector 311D. However, in the door closed state (door closed end) shown in FIG. 4B, the inspection target light receiver 321C receives the light beam L11 from the projector 311D. Therefore, it can be determined that the dirt 400 is not attached to the inspection target light projector 311C side, but is attached to the inspection target light receiver 321C side.

  FIG. 5 shows a detection method in the case where the light amount of the light beam is reduced due to performance deterioration of the projector 311 or the like. FIG. 5A shows the inspection in the door open state, and the inspection target light receiver 321C cannot receive the light beam L20 from the inspection target light projector 311C, and is in a light shielding state. FIG. 5B shows the inspection in the door-closed state, and the inspection target light receiver 321C receives the light beam L20 from the inspection target light projector 311C.

  As shown to Fig.5 (a), the light projector 311B adjacent to the upper side of the test object projector 311C is made effective, and the light ray L21 is output. The light beam L21 is received by the inspection target light receiver 321C with a sufficient amount of light. The light projector 311D adjacent to the lower side of the light projector 311C to be inspected is enabled to output the light beam L22. The light beam L22 is also received by the inspection light receiver 321C with a sufficient amount of light. From these results, it can be seen that the light beam L20 from the inspection target projector 311C has insufficient light amount (or does not emit light at all).

  Next, the light receiver 321B adjacent to the upper side of the inspection target light receiving unit 321C is enabled, and the light beam L23 is output from the inspection target projector 311C. The light receiver 321B cannot receive the light beam L23 with a sufficient amount of light, and is determined to be in a light shielding state. Similarly, the light receiver 321D adjacent to the lower side of the inspection target light receiver 321C is enabled, and the light beam L24 is output from the inspection target light projector 311C. The light receiver 321D cannot receive the light beam L24 with a sufficient amount of light, and is determined to be in a light shielding state. From these results, the inspection target light projecting unit 311C cannot supply a sufficient amount of received light to the light receivers 321B and 321D adjacent above and below the inspection target light receiver 321C, that is, the light quantity of the inspection target light projector 311C is insufficient. Can be determined.

  5B, the light beam L20 from the inspection target projector 311C is received by the inspection target light receiver 321C with a sufficient amount of light. Since the intensity of light is inversely proportional to the square of the distance, when the distance between the light projector 311C and the light receiver 321C decreases, the amount of the light beam L20 incident on the light receiver 321C increases, and it is determined that the light is received. Therefore, it can be determined that the cause is a shortage of light due to aging degradation or the like of the inspection target light projecting unit 311C.

  FIG. 6 is a flowchart showing a self-diagnosis process when the receiver side is opened. FIG. 5 corresponds to the configuration of FIG. As described above, the door control device 210 enables the inspection target projector 311C to output the light beam L10 (S20). Outputting the light beam is expressed as turning on the projector in the flowchart.

  The door control unit 210 acquires a signal from the inspection target light receiver 321C (S21). The door control unit 210 enables the light projector 311D adjacent to the inspection target projector 311C to output the light beam L11 (S22), and acquires the signal of the inspection target light receiver 321C (S23).

  The door control unit 210 determines whether the detection signal of the inspection target light receiver 321C has changed between the time of receiving the light beam L10 (S21) and the time of receiving the light beam L11 (S23) (S24). When the signal indicating the amount of received light has changed (S24: YES), it can be determined that the inspection target light receiver 321C is normal (S25).

  When the detection signal of the inspection target light receiver 321C does not change (S24: NO), the door control unit 210 determines whether a light beam is output from a projector within a predetermined range (S26). When there is an unused projector 311E among the projectors within a predetermined range from the inspection target projector 311C (S26: NO), the door control unit 210 selects the projector 311E and outputs the light beam L12 (S27). The signal of the light receiver 321C is output (S28).

  The door control device 210 returns to step S24 and determines whether the signal of the inspection target light receiver 321C has changed. In this way, if the signal of the inspection target light receiver 321C does not change even if light is successively output from all the light projectors within the predetermined range from the inspection target light projector 311C (S26: YES), the inspection target light receiver 321C It can be determined that there is an abnormality (S29).

  FIG. 7 is a flowchart showing self-diagnosis processing in the door-closed state on the light receiver side. FIG. 7 corresponds to the configuration of FIG. First, the door control device 210 outputs the light beam L10 from the inspection object projector 311C (S40), and acquires the signal of the inspection object light receiver 321C (S41).

  Next, the door control device 210 outputs the light beam L11 from the light projector 311D adjacent to the inspection target light projector 311C (S42), and determines whether the inspection target light receiver 321C is in a light receiving state (S43). When the inspection light receiver 321C does not enter the light receiving state (S43: NO), it can be determined that the inspection light receiver 321C is abnormal (S44).

  When the inspection target light receiver 321C is in a light receiving state (S43: YES), the door control device 210 determines whether the self-diagnosis process at the time of opening the door is in a light shielding state (NO in S24 in FIG. 6). (S45). In the self-diagnosis process when the door is open, when the inspection light receiver 321C has received the light beam L11 from the light projector 311D (S45: NO), it can be determined that the inspection light projector 311C has an abnormality (S46).

  In the self-diagnosis process when the door is opened, when the inspection light receiver 321C cannot receive the light beam L11 from the projector 311D (S45: YES), it is determined that the dirt 400 is attached to the inspection light receiver 321C side. (S47).

  FIG. 8 is a flowchart showing the self-diagnosis process in the door open state on the projector side. FIG. 8 corresponds to the configuration of FIG. The door control device 210 outputs the light beam L21 from the projector 311B adjacent to the upper side of the inspection target projector 311C (S50), and acquires the signal of the inspection target light receiver 321C (S51). The door control device 210 determines whether or not the inspection light receiver 321C is in a light receiving state (S52), and if it is in a light blocking state (S52: NO). It is determined that there is an abnormality in the inspection target light receiver 321C (S60).

  When the inspection target light receiver 321C is in a light receiving state (S52: YES), the door control device 210 outputs the light beam L22 from the light projector 311D adjacent to the lower side of the inspection target light projector 311C (S53), and the inspection target light receiver 321C. A signal is acquired (S54).

  The door control device 210 determines whether or not the inspection target light receiver 321C is in a light receiving state (S55). If the inspection target light receiver 321C is not in a light receiving state (S55: NO), the door control device 210 determines that there is an abnormality in the inspection target light receiver 321C (S60).

  When the inspection target light receiver 321C is in a light receiving state (S55: YES), the door control device 210 outputs a light beam L20 from the inspection target light projector 311C (S56), and adjacent light receivers 321B above and below the inspection target light receiver 321C, Each of the 321D signals is acquired (S57).

  The door control device 210 determines whether or not the light receivers 321B and 321D are in a light receiving state (S58). If each of the light receivers 321B and 321D is in a light receiving state (S58: YES), only the result is stored and the process ends. In contrast, when each of the light receivers 321B and 321D is not in a light receiving state (S58: NO), the door control device 210 determines that there is an abnormality in the inspection target light projector 311C (S59).

  FIG. 9 is a flowchart of the self-diagnosis process in the door-closed state on the projector side. FIG. 9 corresponds to the configuration of FIG. The door control device 210 outputs the light beam L20 from the inspection target light projector 311C (S70), acquires the signal of the inspection target light receiver 321C (S71), and determines whether the inspection target light receiver 321C is in a light receiving state (S72). .

  When the inspection target light receiver 321C is in a light receiving state (S72: YES), it is determined that the inspection target light projector 311C has an abnormality. When the inspection light receiver 321C is in a light-shielded state (S72: NO), only the result is stored and the process is terminated.

  FIG. 10 is an example of a self-diagnosis result screen G10 that is transmitted from the control center 50 to the information terminal 60 of the maintenance worker and displayed. This screen G10 includes, for example, a name for specifying an elevator to be inspected, information for specifying a door sensor to be inspected, and information indicating a self-diagnosis result of the inspection target door sensor.

  Here, “N3 on-N3R off” in FIG. 10 means that a light beam is output from the N3 th projector, but the N3 th photoreceiver constituting the pair is in a light shielding state. Similarly, “N4 ON-N3R ON” means that the inspection target light receiver (N3R) has received a light beam from the light projector (N4) adjacent to the inspection target light projector (N3).

  The information indicating the result of the self-diagnosis may include diagnosis advice. As advice of diagnosis, there are, for example, “There is a possibility of dirt on the light receiver side”, “There is a possibility that the light quantity of the projector is reduced”, and the like. As described above, one or more causes derived from the result of the self-diagnosis may be displayed on the screen G10.

  According to the present embodiment configured as described above, the self-diagnosis can be performed only on the door sensors (311 and 321) to be inspected in a series of opening / closing operations of the car 11, and the inspection can be completed promptly. Can do. Therefore, it is not necessary to stop the elevator only for self-diagnosis, and the service can be prevented from being lowered.

  Furthermore, in this embodiment, since the result of self-diagnosis can be transmitted to the control center 50, maintenance workers who have prepared for the cause of the failure can be promptly sent to the site, and the maintenance service can be improved. .

  Furthermore, in this embodiment, the result of the self-diagnosis is also displayed on the maintenance worker's terminal 60, so that the maintenance worker can prepare and go to the site, and can reduce the time required to isolate the cause of the failure. As a result, the workability of maintenance work is improved.

  In addition, this invention is not limited to the Example mentioned above. A person skilled in the art can make various additions and changes within the scope of the present invention.

  DESCRIPTION OF SYMBOLS 10: Elevator apparatus, 11: Car, 15: Door, 20: Elevator control apparatus, 210: Door control apparatus, 311: Light projector, 321: Light receiver

Claims (6)

In an elevator system that controls an elevator that operates between multiple floors,
A car body reciprocating up and down between the floors;
A pair of doors for opening and closing the doorway of the car body;
A plurality of projectors provided at a predetermined interval on one of the doors;
A plurality of light receivers provided at predetermined intervals apart from the other of the doors so as to form a pair with a corresponding light projector among the light projectors;
A door control device that determines the presence or absence of an abnormal state based on the amount of light received by the light receiver for each of the plurality of pairs, and controls the opening and closing of the door;
The door control device performs a predetermined inspection on an inspection target pair that is determined to satisfy a predetermined inspection condition that is a pair that has detected the abnormal state among the plurality of pairs. And
In the predetermined inspection, the inspection target light projector and the inspection target light receiver constituting the inspection target pair, and another light projector located within a predetermined range of the inspection target light projector, or within a predetermined range of the inspection target light receiver Inspecting the state of the pair to be inspected by using at least one of the other light receivers located in a predetermined combination,
Elevator system. The predetermined inspection condition is a case where the abnormal state continues even if the door is forcibly opened and closed after the abnormal state is continuously detected for a predetermined time or more.
The elevator system according to claim 1. The predetermined inspection is executed in each of an open state and a closed state of the door.
The elevator system according to claim 2. The other projector is a projector capable of outputting light that can be received by the inspection target receiver among the plurality of projectors,
The other light receiver is a light receiver capable of receiving light output from the inspection target projector among the plurality of light receivers.
The elevator system according to claim 3. The door control device can output the result of the predetermined inspection to the outside.
The elevator system according to claim 4. In the elevator system inspection method for automatically inspecting elevators operating between multiple floors,
One of the pair of doors for opening and closing the doorway of the car body is provided with a plurality of light projectors separated by a predetermined interval,
The other of the doors is provided with a plurality of light receivers spaced apart by a predetermined distance so as to form a pair with the light projectors facing each other among the plurality of light projectors,
Determine the presence or absence of an abnormal state based on the amount of light received by the light receiver for each of the plurality of pairs,
Forcibly opening and closing the door after a lapse of a predetermined time after the abnormal state is detected,
If the abnormal state continues even if the door is forcibly opened and closed, select the pair that detected the abnormal state as an inspection target pair,
Inspection target light projector and inspection target light receiver constituting the inspection target pair, and other light projectors positioned within a predetermined range of the inspection target light projector, or other light receivers positioned within a predetermined range of the inspection target light receiver Inspecting the state of the pair to be inspected by using at least one of the above in a predetermined combination,
Elevator system inspection method.

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