JP2014086780A - Radio sensor network system for elevator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automate connection setting of radio communication between a sensor terminal and a radio base station to reduce the burden of a maintenance man.SOLUTION: Sensor terminals 20a, 20b... in response to a search signal from a radio base station 21, transmit to the radio base station 21 sensor installation information indicating at least a sensor type and an installation position, master setting information indicating presence/absence of the master setting, connection information including radio wave strength information indicating radio wave strength with the radio base station 21, together with address information for radio connection. The radio base station 21, on the basis of the connection information received from the sensor terminals 20a, 20b..., determines a sensor terminal which satisfies predetermined conditions as a connection object and registers an address of the sensor terminal to perform connection setting for radio communication.

Description

  Embodiments of the present invention relate to an elevator wireless sensor network system that measures data necessary for failure diagnosis using a sensor having a wireless function (hereinafter referred to as a sensor terminal) and collects the data wirelessly. .

  In wireless sensor network systems used in elevators, sensor terminals called “sensor nodes” are installed at each location of the elevator, and measurement is performed by sensors (acceleration sensors, temperature sensors, noise sensors, etc.) mounted on the sensor terminals. The collected data is collected by radio to make the inspection of the elevator more efficient.

  In the data collection by the wired system, it is necessary to change the sensor to be used and the mounting position depending on the elevator shape and the drive system. On the other hand, in the wireless system, the degree of freedom for adding and installing sensors is improved. Further, since the sensor terminal can be controlled wirelessly, remote measurement processing is possible. Furthermore, it is not necessary to install a relay device for each elevator by using radio, and it is possible to collect data of a plurality of elevators collectively within the radio wave range of the radio base station.

  Here, in order to realize wireless communication between the sensor terminals installed in each part of the elevator and the wireless base station in the hoistway, it is necessary to set the address of each sensor terminal in the wireless base station. is there. Normally, connection settings for wireless communication including such address settings are manually performed by maintenance personnel confirming the address of each sensor terminal with the monitoring center.

JP 2007-300572 A

  As described above, in the elevator wireless sensor network system, the wireless communication connection setting between the sensor terminal and the wireless base station is very troublesome and burdens maintenance personnel. In addition, the sensor terminal has a configuration in which the sensor unit and the wireless unit can be exchanged, and only the failure part can be exchanged at the time of failure or the like. Therefore, it is necessary to perform similar wireless communication connection settings for each exchange.

  The problem to be solved by the present invention is to provide a wireless sensor network system for an elevator that can reduce the burden on maintenance personnel by automating connection settings for wireless communication between a sensor terminal and a wireless base station. It is.

  The elevator wireless sensor network system according to the present embodiment is installed in each part of the elevator, and is installed in a hoistway with a plurality of sensor terminals capable of wireless communication for measuring data necessary for failure diagnosis. It consists of a radio base station that collects data measured by a terminal.

  Each of the sensor terminals responds to a search signal from the radio base station, together with address information for wireless connection, at least sensor installation information indicating a sensor type and an installation position, master setting information indicating presence / absence of master setting, Response means for transmitting connection information including radio field intensity information indicating radio field intensity with the radio base station to the radio base station is provided.

  Based on the connection information received from the sensor terminals, the radio base station is determined as a connection target by a connection target determination unit that determines a sensor terminal that satisfies a predetermined condition as a connection target, and the connection target determination unit. Connection setting means for registering the address of the sensor terminal and setting the connection for wireless communication.

FIG. 1 is a diagram illustrating a configuration of an elevator according to an embodiment. FIG. 2 is a block diagram showing the configuration of the elevator wireless sensor network system in the embodiment. FIG. 3 is a diagram showing a configuration of device information of the sensor terminal of the wireless sensor network system in the embodiment. FIG. 4 is a flowchart showing a processing operation related to connection setting at the initial time of the wireless base station of the wireless sensor network system in the embodiment. FIG. 5 is a flowchart showing a processing operation related to the initial connection setting of the wireless sensor network system in the embodiment. FIG. 6 is a flowchart showing a processing operation for checking the linkage with the elevator operation of the wireless base station of the wireless sensor network system in the embodiment. FIG. 7 is a diagram showing a search operation of a plurality of sensor terminals by the wireless base station of the wireless sensor network system in the same embodiment.

  Hereinafter, embodiments will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration of an elevator according to an embodiment. In the example of FIG. 1, the configuration of a machine room race type elevator is shown, but the present invention is not particularly limited to a machine room race type elevator, and is applicable to any type of elevator. Is possible.

  Guide rails 11 and 12 are erected in an elevator hoistway 10, and a car 13 is installed on the guide rail 11, and a counterweight 14 is installed on the guide rail 12 so as to be raised and lowered.

  A small hoisting machine 15 is installed in the upper part of the hoistway 10, and a car 13 is provided at one end of the main rope 16 wound around the hoistway 10, and a counterweight 14 is provided at the other end of the main rope 16 at 2: 1. Connected by roving. Thereby, when the hoisting machine 15 is rotationally driven, the car 13 and the counterweight 14 are lifted and lowered in a slidable manner via the main rope 16.

  In the machine room race type, an elevator control device 17 is installed in the upper part of the hoistway 10 together with the hoisting machine 15. The control device 17 is a so-called “control panel”, and includes a computer having a CPU, a ROM, a RAM, and the like, and performs operation control of the entire elevator including drive control of the hoisting machine 15.

  Here, sensor terminals 20a, 20b,... Are installed at each location of the elevator including the car 13 as a moving body. In the example of FIG. 1, the sensor terminal 20a is installed in the vicinity of the door 18 of the car 13, and the sensor terminal 20b is installed in the vicinity of the door opening / closing mechanism 19. It is assumed that it is installed in.

  The sensor terminals 20a, 20b,... Are also called “sensor nodes”, have a built-in wireless communication function with the sensor, and transmit data measured by the sensor to the external wireless base station 21 by wireless communication. Examples of the sensor type include a temperature sensor, an acceleration sensor, a sound sensor, a voltage sensor, a current sensor, a temperature sensor, and the like, which are properly used depending on the content of the device failure diagnosis.

  The radio base station 21 is also called a “gateway”, is installed in the upper part of the hoistway 10, and is connected to the control device 17 by a transmission cable (not shown). In the example of FIG. 1, the control device 17 and the radio base station 21 are individually installed, but the function of the radio base station 21 may be provided in the control device 17.

  When the sensor terminals 20a, 20b... Are slaves, the wireless base station 21 becomes a master that performs wireless communication with these slaves. The wireless base station 21 wirelessly connects to the sensor terminals 20a, 20b ... within a predetermined wireless communication range, and collects data measured by the sensor terminals 20a, 20b ....

  FIG. 2 is a block diagram showing a configuration of an elevator wireless sensor network system. The same parts as those in FIG.

  The system includes a plurality of sensor terminals 20a, 20b, and a radio base station 21 that performs radio communication between the sensor terminals 20a, 20b, and so on. As shown in FIG. 1, the sensor terminals 20 a, 20 b... Are installed at each location of the elevator including the car 13. The radio base station 21 is installed in the hoistway 10.

  Each of the sensor terminals 20a, 20b,... Includes a measurement sensor 31, a CPU 32, and a wireless unit 33.

  The sensor 31 includes, for example, a temperature sensor, an acceleration sensor, a sound sensor, a voltage sensor, a current sensor, a temperature sensor, and the like, and is exchangeably mounted in the sensor terminals 20a, 20b. Two types of sensors (sensors 1 and 2 in the figure) can be mounted in one sensor terminal.

  The CPU 32 controls the entire sensor terminal, such as transmission processing of data measured by the sensor 31. In this embodiment, in response to the search signal from the radio base station 21, the CPU 32 includes at least sensor installation information indicating the sensor type and installation position, as well as master information indicating the presence / absence of master setting, together with address information for wireless connection. A response unit 32 a that transmits connection information including setting information and radio wave intensity information indicating radio wave intensity between the radio base station 21 and the radio base station 21 is provided.

  The radio unit 33 performs radio communication in a predetermined frequency band with an external device (here, the radio base station 21). As a wireless communication method, a generally known method is used, and detailed description thereof is omitted here.

  On the other hand, the radio base station 21 includes two radio units 41 and 42, a CPU 43, a storage unit 44, and an external communication unit 45.

  The wireless unit 41 is wirelessly connected to a wireless unit 33 provided in the sensor terminals 20a, 20b, and performs wireless communication in a predetermined frequency band. The same applies to the wireless unit 42, and wireless communication is possible with the sensor terminals 20a, 20b.

  The CPU 43 performs overall control of the radio base station such as connection processing to the sensor terminals 20a, 20b. In this embodiment, the CPU 43 includes a connection target determination unit 43a that determines a sensor terminal that satisfies a predetermined condition as a connection target based on the connection information received from the sensor terminals 20a, 20b, and the connection target determination unit. There is provided a connection setting unit 43b for registering the address of the sensor terminal determined to be connected by 43a and performing connection setting for wireless communication.

  Further, the CPU 43 outputs a radio wave intensity measurement command to the sensor terminals 20a, 20b... During the operation of the elevator, and the connection setting for the sensor terminals 20a, 20b. A setting confirmation unit 43c that determines whether or not the connection setting is correct and deletes the information of the sensor terminal when the connection setting is incorrect is provided.

  The storage unit 44 stores data measured by the sensor terminals 20a, 20b,. The storage unit 44 is provided with a database 44a. The database 44a stores information (address, etc.) related to connection settings of the sensor terminals 20a, 20b.

  The external communication unit 45 controls communication with an external remote monitoring center 51 via a communication network 50 such as a telephone public network. The measurement data stored in the storage unit 44 is sent from the external communication unit 45 to the remote monitoring center 51 via the communication network 50 at a predetermined timing.

  The remote monitoring center 51 exists in a remote place, and performs display / data storage / analysis based on the measurement data sent from the radio base station 3. The remote monitoring center 51 is also connected to the control device 17 shown in FIG. The remote monitoring center 51 acquires information related to the operation state of the elevator from the control device 17 via the communication network 50 to determine whether there is an abnormality. If any abnormality is detected, the remote monitoring center 51 responds by dispatching a maintenance staff to the site. To do.

  FIG. 3 is a diagram showing a configuration of device information of the sensor terminals 20a, 20b... In this system.

  The device information of the sensor terminals 20a, 20b... Consists of address information 61 and connection information 62. The address information 61 includes an address for wireless connection and a security passcode. The connection information 62 includes sensor installation information 63 indicating the sensor type and installation position (sensor 1 and sensor 2 type and port number), master setting information 64 indicating presence / absence of master setting, and radio wave intensity information indicating radio wave intensity. 65.

  In such a configuration, in order to perform wireless communication between the plurality of sensor terminals 20a, 20b... Installed at each location of the elevator and the wireless base station 21 in the hoistway 10, the sensor terminals 20a, 20b are previously provided. It is necessary to set a unique address to the radio base station 21 for. Conventionally, maintenance personnel have been performing operations such as checking the addresses of the sensor terminals 20a, 20b... And setting them to the radio base station 21 one by one.

  In this system, connection settings for wireless communication including such address settings can be automated to reduce the burden on maintenance personnel.

  Hereinafter, operations related to connection settings for wireless communication in this system will be described in detail.

(1) Connection setting at initial time First, connection setting in the case of performing wireless communication between the sensor terminals 20a, 20b... Installed in each part of the elevator and the radio base station 21 in the hoistway 10 A description will be given separately for the processing operation of the radio base station and (b) the processing operation of the sensor terminal.

(A) Processing Operation of Radio Base Station FIG. 4 is a flowchart showing a processing operation relating to the initial connection setting of the radio base station 21 in this system. Note that the processing shown in this flowchart is executed by the CPU 43 mounted on the radio base station 21 reading a predetermined program.

  The radio base station 21 transmits a search signal of a specific frequency band to search for the sensor terminals 20a, 20b,... In the network (step A11), and scans the frequencies used by the sensor terminals 20a, 20b,. Step A12).

  If it is now possible to search for the sensor terminal 20a by frequency scanning (Yes in step A13), the radio base station 21 issues a device information disclosure request to the sensor terminal 20a (step A14). If there is no response from the sensor terminal 20a to this disclosure request (No in step A15), the radio base station 21 excludes the sensor terminal 20a from the connection target (step A19).

  When the address information 61 and the connection information 62 are sent as device information from the sensor terminal 20a (Yes in step A15), the radio base station 21 determines the master setting based on the master setting information 64 included in the connection information 62. The presence or absence is checked (step A16).

  Here, when another radio base station is already set as the master in the sensor terminal 20a (No in Step A16), the radio base station 21 excludes the sensor terminal 20a from the connection target (Step A19).

  That is, when a plurality of elevators are installed adjacent to each other, communication with sensor terminals installed in other elevators may be possible. Therefore, first, the presence / absence of the master setting is checked, and if another radio base station is already set as the master, it is determined that the sensor terminal is not under its management and is excluded from the connection target.

  If the master is not set in the sensor terminal 20a (Yes in Step A16), the radio base station 21 subsequently transmits radio waves to and from the sensor terminal 20a based on the radio field intensity information 65 included in the connection information 62. The intensity value is checked (step A17). The radio wave intensity information 65 is measured when the sensor terminal 20 a receives a radio wave from the radio base station 21 and is incorporated in the connection information 62.

  As a result, if the value of the radio field intensity is equal to or greater than a reference value set in advance as a wireless connection condition (Yes in step A17), the wireless base station 21 uses the sensor terminal under its management as the sensor terminal 20a. It is determined that there is a wireless communication connection setting (step A18). Specifically, the address included in the address information 61 received from the sensor terminal 20 a is decoded with a pass code, and registered in the database 44 a of the storage unit 44 together with the sensor installation information 63.

  On the other hand, when the value of the radio field intensity does not satisfy the reference value (No in Step A17), the radio base station 21 determines that the sensor terminal 20a is not a sensor terminal under its management and excludes it from the connection target ( Step A19). That is, when the value of the radio field intensity does not satisfy the reference value, it can be determined that the sensor terminal 20a is installed in a place outside the network range of the wireless base station 21, and therefore it is excluded from the connection target. .

  In this way, the wireless base station 21 selects only the sensor terminals that meet the wireless connection conditions from the sensor terminals 20a, 20b,... Searched by scanning, and performs wireless communication connection settings for the sensor terminals. Information necessary for wireless communication such as the address and sensor type is registered in the database 44a of the storage unit 44.

(B) Processing operation of sensor terminal FIG. 5 is a flowchart showing a processing operation related to the connection setting at the initial time of the sensor terminals 20a, 20b. The processing shown in this flowchart is executed by the CPU 32 mounted on the sensor terminals 20a, 20b... Reading a predetermined program.

Now, in order to simplify the description, the sensor terminal 20a will be described.
When a power switch (not shown) is turned on after the sensor 31 is attached to the sensor terminal 20a (step B11), the CPU 32 displays address information 61, sensor installation information 63, and master setting information 64 as device information of the sensor terminal 20a. It is created and stored in a memory (not shown) (step B12). As shown in FIG. 2, the address information 61 indicates an address and a pass code, the sensor installation information 63 indicates a sensor type and an installation position, and the master setting information 64 indicates the presence / absence of master setting. In the initial state, no master setting is registered in the master setting information 64.

  Here, when the sensor terminal 20a receives a specific search signal from the radio base station 21 and receives a device information disclosure request (Yes in step B13), the sensor terminal 20a measures the radio field intensity with the radio base station 21. (Step B14). Then, the sensor terminal 20a adds the radio wave intensity information 65 indicating the value of the radio wave intensity to the connection information 62 of the device information and responds to the radio base station 21 (step B15).

  If there is a notification of completion of setting from the wireless base station 21 after the response (Yes in Step B16), the sensor terminal 20a recognizes the wireless base station 21 as a master and registers the presence of the master in the master setting information 64 (Step S16). B16).

  The same applies to the other sensor terminals 20b..., And responds to the radio base station 21 including the information on the radio field strength in response to the device information disclosure request from the radio base station 21.

  As described above, the address information 61 of the sensor terminals 20a, 20b... Is expanded, and connection information 62 including sensor installation information 63, master setting information 64, and radio wave intensity information 65 is incorporated in the expanded portion. Thereby, in the wireless base station 21, it is possible to determine only the sensor terminal that satisfies the predetermined condition from the connection information 62 as a connection target, and perform connection setting for wireless communication.

  Therefore, it is not necessary for the maintenance staff to set the addresses of the sensor terminals 20a, 20b, etc. one by one as in the prior art, and after installing the sensor terminals 20a, 20b,. By simply turning ON, it is possible to easily connect to the wireless base station 21 and construct a wireless network.

  Thereafter, data such as noise measured by the sensor terminals 20a, 20b... During the operation of the elevator is sent to the radio base station 21 by radio communication. The radio base station 21 collects measurement data obtained by the sensor terminals 20a, 20b... And stores it in the storage unit 44 and transmits it to the remote monitoring center 51 via the communication network 50 at a predetermined timing. Thereby, the remote monitoring center 51 can grasp the operation state of the elevator based on the measurement data sent from the radio base station 3 without dispatching maintenance personnel to the site.

  The sensor terminals 20a, 20b,... Have a structure in which the sensor 31 or the wireless unit 33 can be freely replaced. The same applies to the case where the sensor 31 or the wireless unit 33 is replaced. Once the parts are replaced and initialized, the wireless communication connection setting with the wireless base station 21 can be automatically performed.

(2) Confirmation of setting In this system, the radio base station 21 has a function of confirming the radio wave intensity of the sensor terminals 20a, 20b,... doing.

  FIG. 6 is a flowchart showing a processing operation for checking the linkage with the elevator operation of the radio base station 21 in this system. Note that the processing shown in this flowchart is executed by the CPU 43 mounted on the radio base station 21 reading a predetermined program.

  Now, in order to simplify the description, the sensor terminal 20a will be described. The sensor terminal 20a is installed in the car 13 as shown in FIG.

  During operation of the elevator, the radio base station 21 receives an elevator (car 13) up / down signal from the control device 17 (step C11). At this time, the radio base station 21 outputs a radio wave intensity measurement command to the sensor terminal 20a (step C12). In response to this measurement command, the sensor terminal 20 a measures the radio wave intensity with the radio base station 21 and returns the measurement result to the radio base station 21.

  Here, the radio base station 21 confirms the measurement result of the radio field intensity received from the sensor terminal 20a (step C13). As a result, when the radio wave intensity changes in conjunction with the elevator ascending / descending operation (Yes in Step C14), the radio base station 21 determines that the connection setting for the sensor terminal 20a is correct, and the storage unit 44 The setting contents stored in the database 44a are held as they are (step C15).

  In the example of FIG. 1, the radio base station 21 is installed at the top of the hoistway 10. Therefore, the radio wave intensity obtained from the sensor terminal 20a installed in the car 13 which is a moving body becomes stronger as the elevator ascends.

  On the other hand, when the radio wave intensity does not change in conjunction with the elevator up / down operation, that is, when there is no change in the radio wave intensity, or when the radio wave intensity changes regardless of the elevator up / down operation (Yes in step C14). ), Likely a sensor terminal installed in another elevator. In such a case, the radio base station 21 determines that there is an error in the connection setting, and deletes the information (address, etc.) of the sensor terminal from the database 44a of the storage unit 44 (step C15).

  The same applies to the other sensor terminals 20b..., It is determined whether the setting is correct from the change in radio field intensity obtained during operation of the elevator, and incorrect settings are deleted appropriately. Accordingly, wireless communication can be performed only for the sensor terminals 20a, 20b,.

  The function of confirming the wireless communication connection setting in conjunction with the elevator operation is applied to a moving body of the elevator, that is, a sensor terminal installed on the car 13 or the counterweight 14.

(3) Search for a plurality of sensor terminals As shown in FIG. 2, the radio base station 21 of this system is provided with a plurality of radio modules (two radio units 41 and 42 in FIG. 2). . The search for sensor terminals at the time of initial setting described above collects information on all sensor terminals to which the first wireless module that has issued the search command may be connected.

  Here, some sensor terminals can be connected to only one wireless module. For example, in the case of a sensor terminal equipped with a sensor that outputs a signal continuously, such as a sound sensor, a situation occurs in which one wireless module is occupied during measurement. For this reason, it is necessary to connect with another sensor terminal by another wireless module.

This is shown in FIG.
Now, description will be made assuming that three sensor terminals 20a, 20b, and 20c (sensor nodes 1-3) are searched.

  While the sensor terminals 20a, 20b, and 20c are activated, the wireless base station 21 is turned on to perform a search. The search at this time is executed by the radio unit 41 of the radio base station 21. That is, the wireless unit 41 receives responses from the three sensor terminals 20a, 20b, and 20c, and obtains connection information (address, etc.).

  Here, only the sensor terminal 20a is connected by the wireless unit 41, and for the other sensor terminals 20a and 20b, connection information (address, etc.) is stored in the database 44a of the storage unit 44 via the CPU 43 in the wireless base station 21. Remember. Then, the wireless unit 42 uses the information of the sensor terminals 20a and 20b stored in the database 44a to perform connection settings for wireless communication.

  In this way, the wireless unit 41 searches all the sensor terminals and stores the information obtained at that time in the database 44a, so that the wireless unit 41 is connected to a certain sensor terminal, and the wireless unit 41 In 42, another sensor terminal can be connected without re-searching using the information stored in the database 44a.

  According to at least one embodiment described above, an elevator wireless sensor network system capable of automating wireless communication connection settings between a sensor terminal and a wireless base station and reducing the burden on maintenance personnel is provided. can do.

  In addition, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Hoistway, 11, 12 ... Guide rail, 13 ... Car, 14 ... Counterweight, 15 ... Hoisting machine, 16 ... Main rope, 17 ... Control device, 18 ... Door, 19 ... Door opening / closing mechanism, 20a, 20b ... sensor terminal, 21 ... radio base station, 31 ... sensor, 32 ... CPU, 32a ... response unit, 33 ... radio unit, 41,42 ... radio unit, 43 ... CPU, 43a ... connection target determination unit, 43b ... connection Setting unit, 43c ... Setting confirmation unit, 44 ... Storage unit, 44a ... Database, 45 ... External communication unit, 50 ... Communication network, 51 ... Remote monitoring center, 61 ... Address information, 62 ... Connection information, 63 ... Sensor installation information 64: Master setting information, 65: Radio wave intensity information.

Claims (5)

A plurality of sensor terminals installed at each location of the elevator and capable of wireless communication for measuring data necessary for failure diagnosis,
In an elevator wireless sensor network system, which is installed in a hoistway and consists of a wireless base station that collects data measured by each of the sensor terminals,
Each sensor terminal is
In response to the search signal from the wireless base station, together with address information for wireless connection, at least sensor installation information indicating the sensor type and installation position, master setting information indicating presence / absence of master setting, between the wireless base station Response means for transmitting connection information including radio field intensity information indicating the radio field intensity to the radio base station,
The radio base station
Based on the connection information received from each of the sensor terminals, a connection target determination unit that determines a sensor terminal that satisfies a predetermined condition as a connection target;
An elevator wireless sensor network system comprising: a connection setting unit configured to register a wireless communication connection setting by registering an address of a sensor terminal determined to be a connection target by the connection target determination unit. In the above wireless base station,
The connection target determining means is
When the master setting information included in the connection information is checked for the presence of master setting, if the master is not set, the sensor terminal is determined as a connection target, and another radio base station is set as the master 2. The elevator wireless sensor network system according to claim 1, wherein the sensor terminal is excluded from connection targets. In the above wireless base station,
The connection target determining means is
The radio field strength between each of the sensor terminals and the radio base station is checked from the radio field intensity information included in the connection information, and the radio field intensity value is equal to or higher than a reference value set in advance as a wireless connection condition. 2. The elevator wireless sensor network system according to claim 1, wherein the sensor terminal is determined as a connection target, and if the reference value is not satisfied, the sensor terminal is excluded from the connection target. The radio base station
During operation of the elevator, a radio wave intensity measurement command is output to each sensor terminal, and it is determined whether or not the connection setting for each sensor terminal is correct from the change in radio wave intensity obtained as a result of the measurement. 2. The elevator wireless sensor network system according to claim 1, further comprising setting confirmation means for deleting the information of the sensor terminal when the error is incorrect. In the above wireless base station,
The above setting confirmation means
It is judged that the connection setting is correct when the signal strength changes in conjunction with the elevator up / down operation, and the connection setting is incorrect when the signal strength does not change in conjunction with the elevator up / down operation. The elevator wireless sensor network system according to claim 4, wherein:

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