Emergency stop system for construction machine, emergency stop device, and method for controlling emergency stop device

Abstract

To prevent communication between an emergency stop device and a construction machine from being disabled by radio wave interference when the construction machine automatically operated in a construction site is stopped by digital radio from the emergency stop device.SOLUTION: Each of the plurality of emergency stop apparatuses includes a position information acquisition unit 53 that acquires position information of the emergency stop apparatus, a position information communication unit 54 that acquires position information of the other emergency stop apparatuses, a distance determination unit 55 that calculates a distance between the position information of the emergency stop apparatus and the other position information and determines whether or not the distance is equal to or less than a threshold value H, and a warning unit 56 that warns that the stop signal cannot be transmitted to the construction machine 2 when the distance is equal to or less than the threshold value H.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an emergency stop system, an emergency stop device, and a control method for an emergency stop device for a construction machine. [Background technology]

[0002] Construction machinery is being operated automatically to resolve labor shortages and improve productivity and safety. If such automatically operating construction machinery malfunctions, it must be brought to an emergency stop. For this reason, construction machinery is sometimes configured to stop when it receives a stop signal, and construction machinery monitors are sometimes required to carry emergency stop devices that transmit a stop signal to the construction machinery via digital radio to stop the automatic operation of the construction machinery. In this case, if the construction machinery malfunctions, the monitor can visually or otherwise confirm the malfunction and operate the emergency stop device to send a stop signal to the construction machinery, thereby stopping the construction machinery. In such a configuration, if the emergency stop device malfunctions or the battery runs out while the construction machine is operating automatically, the emergency stop device will be unable to send a stop signal to the construction machine. If the distance between the emergency stop device and the construction machine becomes too great or an obstacle is placed between them, causing communication to be cut off, the emergency stop device may be unable to send a stop signal to the construction machine. In such a case, the emergency stop device will be unable to stop the automatic operation of the construction machine.

[0003] In this regard, Patent Document 1 discloses an emergency stop system for construction machinery, which includes a construction machinery, multiple emergency stop devices, and a stop control device. The construction machinery is capable of autonomous travel. The emergency stop device is for bringing the construction machinery to an emergency stop. The stop control device is provided on the construction machinery and controls the stopping of the construction machinery's operation. The emergency stop device has a representative acceptance unit that determines which of the multiple emergency stop devices it will be the representative. The representative acceptance unit is configured to accept operations from a monitor when wireless communication is possible between the emergency stop device and the stop control device. The stop control device stops the operation of the construction machinery when wireless communication from the representative emergency stop device to the stop control device becomes impossible. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2024-039904 Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, at large-scale construction sites, multiple monitors may be mobilized, for example, when it is necessary to closely monitor a single construction machine, or when multiple construction machines are introduced at a construction site and one monitor cannot monitor all of the construction machines. In such cases, each of the multiple monitors will carry an emergency stop device. In such cases, for example, if a monitor moves and gets close to other monitors as the construction machines move, the multiple emergency stop devices may come close to each other, and radio wave interference between the emergency stop devices may cause communication between the emergency stop devices to become impossible. In this way, when multiple emergency stop devices are close to each other and communication from the emergency stop devices to the construction machinery is not possible, if a mechanism is not provided to stop the operation of the construction machinery when wireless communication from the emergency stop devices to the construction machinery becomes impossible, as in Patent Document 1, even if an attempt is made to send a stop signal from the emergency stop device, the stop signal will not be sent because communication is not possible, and the automatic operation of the construction machinery cannot be stopped.

[0006] Furthermore, in a case where a mechanism is provided to stop the operation of a construction machine when wireless communication from an emergency stop device to the construction machine becomes impossible, as in Patent Document 1, if multiple emergency stop devices are placed close to each other and radio wave interference between the emergency stop devices causes communication between the emergency stop devices and the construction machine to become impossible, the construction machine will not receive wireless communication. As a result, the construction machine will stop operating automatically even if it is not desired to stop it. This may reduce the processing efficiency of the construction machine. When automatically operating construction machinery at a construction site is stopped by transmitting a stop signal via digital radio from a portable emergency stop device, it is desirable to prevent the emergency stop devices from coming too close to each other, resulting in radio wave interference that disables communication between the emergency stop devices and the construction machinery.

[0007] The problem that the present invention aims to solve is to provide an emergency stop system, an emergency stop device, and a control method for an emergency stop device for construction machinery that can prevent communication between the emergency stop devices and the construction machinery from becoming impossible due to radio wave interference caused by emergency stop devices coming too close to each other when automatically operating construction machinery at a construction site is stopped by transmitting a stop signal via digital radio from a portable emergency stop device. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention employs the following means. That is, the emergency stop system for construction machinery of the present invention is an emergency stop system for construction machinery comprising a construction machinery that operates automatically within a construction site, and a plurality of portable emergency stop devices that transmit stop signals to the construction machinery by digital wireless communication to stop the automatic operation of the construction machinery, wherein the construction machinery comprises a drive source, a construction machinery control unit that controls the drive source to operate the construction machinery automatically, a signal receiving unit that receives the stop signals from the plurality of emergency stop devices, and a stop control unit that stops the drive source when the stop signal is received, and each of the plurality of emergency stop devices receives a stop command that stops the automatic operation of the construction machinery. a signal transmitting unit that transmits the stop signal to the construction machine by digital wireless when the input of the stop instruction is received; a position information acquiring unit that acquires its own position information; a position information communication unit that communicates wirelessly with the other emergency stop devices and transmits its own position information to the other emergency stop devices and acquires the position information of the other emergency stop devices as other position information; a distance determining unit that calculates the distance between the own position information and the other position information and determines whether the distance is equal to or less than a threshold value; and a warning unit that warns that the stop signal will not be able to be transmitted to the construction machine if the distance is equal to or less than the threshold value.

[0009] According to the above-described configuration, the emergency stop system for construction machinery includes a construction machinery that operates automatically within a construction site, and a plurality of portable emergency stop devices that transmit a stop signal to the construction machinery via digital wireless communication to stop the automatic operation of the construction machinery. The construction machinery is operated automatically by a construction machinery control unit controlling the drive source. The emergency stop devices can be carried by a supervisor or the like who monitors the construction machinery. When the construction machinery malfunctions, the supervisor who confirms the malfunction inputs a stop instruction to the emergency stop device to stop the automatic operation of the construction machinery. When the stop instruction input receiving unit receives the input of this stop instruction, the signal transmitting unit transmits a stop signal to the construction machinery via digital wireless communication. On the construction machinery side, the signal receiving unit receives the transmitted stop signal, and the stop control unit stops the drive source. In this way, the supervisor or the like can use the emergency stop devices to stop the automatically operating construction machinery. When multiple emergency stop devices transmitting via digital radio are located close to each other, radio wave interference between the emergency stop devices may prevent communication between the emergency stop devices and the construction machine. In such cases, if a configuration is not provided with a mechanism for transmitting and receiving a communication status confirmation signal between the emergency stop device and the construction machine, and for stopping the automatic operation of the construction machine when the communication status confirmation signal is not received by the construction machine and communication is impossible, it becomes impossible to stop the automatic operation of the construction machine. Furthermore, if such a mechanism is provided, the construction machine may stop even when it is not desired to stop the automatic operation of the construction machine, which could reduce the processing efficiency of the construction machine. In contrast, in the above-described configuration, each of the multiple emergency stop devices includes a location information acquisition unit that acquires its own location information, a location information communication unit that wirelessly communicates with other emergency stop devices, transmits its own location information to the other emergency stop devices, and acquires the location information of the other emergency stop devices as the other location information, a distance determination unit that calculates the distance between its own location information and the other location information and determines whether the distance is equal to or less than a threshold, and a warning unit that warns that a stop signal cannot be transmitted to the construction machine if the distance is equal to or less than the threshold. With this configuration, if monitors, etc., get too close to each other and the distance between the emergency stop devices becomes equal to or less than the threshold, the warning unit of the emergency stop device warns that a stop signal cannot be transmitted to the construction machine. Based on this warning, monitors, etc., can confirm that they are approaching other monitors, etc. In this case, a moving monitor, etc., can increase the distance between them by moving in the opposite direction. Alternatively, a monitor who confirms that other monitors, etc. are approaching can avoid further proximity between the monitors by moving in the same direction as the other moving monitors. In this way, it is possible to avoid close proximity between monitors, i.e., between emergency stop devices, thereby preventing the emergency stop devices from coming close to each other and causing radio wave interference that makes communication between the emergency stop devices and the construction machinery impossible.

[0010] In one aspect of the present invention, while the construction machine is operating automatically, a communication status confirmation signal is transmitted from the signal transmitting unit of each of the plurality of emergency stop devices to the signal receiving unit of the construction machine at regular time intervals, and the stop control unit stops the drive source if the communication status confirmation signal is not received.

[0011] For example, communication from the signal transmitting unit of the emergency stop device to the signal receiving unit of the construction machine may become impossible due to a malfunction of the emergency stop device, a low remaining battery charge for the emergency stop device, etc. In such a case, even if a supervisor or the like wants to stop the automatic operation of the construction machine, the automatic operation of the construction machine cannot be stopped because communication from the emergency stop device to the construction machine is not possible, and the construction machine continues to operate automatically. In contrast, in the above-described configuration, while the construction machine is operating automatically, a communication status confirmation signal is transmitted from the signal transmitting unit of each of the multiple emergency stop devices to the signal receiving unit of the construction machine at regular time intervals. Furthermore, on the construction machine side, the stop control unit stops the drive source if the communication status confirmation signal is not received. Therefore, if communication from the signal transmitting unit of the emergency stop device becomes impossible, the construction machine will no longer be able to receive the communication status confirmation signal, and the stop control unit will stop the drive source of the construction machine, thereby stopping the automatic operation of the construction machine. In this way, the automatic operation of the construction machine is automatically stopped when communication is lost, which prevents the construction machine from continuing to operate automatically even if a supervisor or other person wants to stop the automatic operation of the construction machine, as communication between the emergency stop device and the construction machine is not possible.

[0012] In one aspect of the present invention, each of the plurality of emergency stop devices includes a threshold setting unit that can set the threshold value.

[0013] With this configuration, the threshold setting unit can appropriately set the distance threshold between its own location information and other location information for each of the multiple emergency stop devices, depending on the type of digital radio used, the number and placement of monitors carrying multiple emergency stop devices, etc., and warn that the device will no longer be able to send a stop signal to the construction machinery.

[0014] The emergency stop device of the present invention is configured to be portable and transmits a stop signal via digital wireless to construction machinery operating automatically within a construction site to stop the automatic operation of the construction machinery, and is characterized by comprising: a stop instruction input receiving unit that receives input of a stop instruction to stop the automatic operation of the construction machinery; a signal transmitting unit that transmits the stop signal via digital wireless to the construction machinery when input of the stop instruction is received; a location information acquiring unit that acquires its own location information; a location information communication unit that communicates wirelessly with the outside, transmits its own location information to the outside, and acquires other location information from the outside that is different from its own location information; a distance determination unit that calculates the distance between the own location information and the other location information and determines whether the distance is equal to or less than a threshold; and a warning unit that warns that the stop signal will not be able to be transmitted to the construction machinery if the distance is equal to or less than the threshold.

[0015] According to the above configuration, the emergency stop device is portable and transmits a stop signal to the construction machine via digital wireless communication to stop the automatic operation of the construction machine. Such an emergency stop device can be carried by a supervisor or the like who monitors the construction machine. When the construction machine malfunctions, the supervisor confirms the malfunction and inputs a stop command to the emergency stop device to stop the automatic operation of the construction machine. When the stop command input receiving unit receives the input of this stop command, the signal transmitting unit transmits a stop signal to the construction machine via digital wireless communication. On the construction machine side, reception of the transmitted stop signal can be used as a trigger to stop the automatic operation. However, in cases where multiple monitors are mobilized at a construction site and each of them carries an emergency stop device, if a monitor moves and approaches other monitors as construction machinery moves, for example, the multiple emergency stop devices may come close to each other, and radio wave interference between the emergency stop devices may prevent communication from the emergency stop devices to the construction machinery. In contrast, in the above-described configuration, the emergency stop device includes a location information acquisition unit that acquires its own location information, a location information communication unit that wirelessly communicates with the outside world, transmits its own location information to the outside world, and acquires other location information different from its own location information from the outside world, a distance determination unit that calculates the distance between its own location information and the other location information and determines whether the distance is equal to or less than a threshold, and a warning unit that warns that a stop signal cannot be transmitted to the construction machine if the distance is equal to or less than the threshold. Therefore, in a case where multiple monitors each carry an emergency stop device, each emergency stop device can communicate with nearby other emergency stop devices as an external device, transmit its own location information to the other emergency stop devices, and acquire other location information from the other emergency stop devices as the location information of the other emergency stop devices. In this case, if monitors get too close to each other and the distance between the emergency stop devices becomes equal to or less than the threshold, the warning unit of the emergency stop device warns that a stop signal cannot be transmitted to the construction machine. Based on this warning, monitors can confirm their proximity to other monitors. In this case, a moving observer can increase the distance between himself and the other observers by turning around and moving in the opposite direction. Alternatively, an observer who has confirmed that another observer is approaching can move in the same direction as the other observer to avoid further proximity between the observers. In this way, it is possible to avoid close proximity between monitors, i.e., between emergency stop devices, thereby preventing the emergency stop devices from coming close to each other and causing radio wave interference that makes communication between the emergency stop devices and the construction machinery impossible.

[0016] In one aspect of the present invention, the emergency stop device of the present invention includes a threshold setting unit that can set the threshold value.

[0017] With this configuration, the threshold setting unit can appropriately set a threshold value for the distance between the location information of one device and the location information of another device, which will warn each of the multiple emergency stop devices that it will no longer be able to send a stop signal to the construction machine.

[0018] The method for controlling an emergency stop device of the present invention is a method for controlling an emergency stop device when multiple portable emergency stop devices are used, each of which transmits a stop signal via digital wireless to construction machinery operating automatically within a construction site to stop the automatic operation of the construction machinery, and is characterized by including the following steps: for each of the multiple emergency stop devices to acquire its own position information; for each of the multiple emergency stop devices to communicate wirelessly with the other emergency stop devices and transmit its own position information to the other emergency stop devices, and acquire the position information of the other emergency stop devices as the other position information; for each of the multiple emergency stop devices to calculate the distance between its own position information and the other position information and determine whether the distance is equal to or less than a threshold; and for each of the multiple emergency stop devices to issue a warning that it will not be able to transmit the stop signal to the construction machinery if the distance is equal to or less than the threshold.

[0019] With this configuration, when multiple portable emergency stop devices are used that transmit stop signals via digital radio to construction machinery operating automatically at a construction site to stop the automatic operation of the machinery, it is possible to prevent the emergency stop devices from coming too close to each other, i.e., to prevent radio wave interference that would cause communication between the emergency stop devices and the construction machinery to become impossible. [Effects of the Invention]

[0020] According to the present invention, when automatically operating construction machinery within a construction site is stopped by transmitting a stop signal via digital radio from a portable emergency stop device, it is possible to prevent the emergency stop devices from coming too close to each other, resulting in radio wave interference that disables communication between the emergency stop devices and the construction machinery. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a diagram showing the configuration of an emergency stop system for a construction machine according to an embodiment of the present invention. [Figure 2]1 is a block diagram showing the functional configuration of a construction machine, a remote control device, and an emergency stop device in an emergency stop system for a construction machine according to an embodiment of the present invention. [Figure 3] FIG. 1 is a diagram showing a construction machine equipped with a signal receiving unit capable of receiving stop signals from a plurality of emergency stop devices. [Figure 4] 1 is a diagram showing an example of the appearance of an emergency stop device according to an embodiment of the present invention; [Figure 5] 3 is a flowchart showing the flow of a control method for the emergency stop device in the present embodiment. [Figure 6] FIG. 10 is a diagram illustrating a state in which the distance between multiple emergency stop devices is greater than a threshold value. [Figure 7] FIG. 10 is a diagram illustrating a state in which the distance between a plurality of emergency stop devices is equal to or less than a threshold value. [Figure 8] FIG. 8 is a diagram showing a state in which, from the state shown in FIG. 7, a monitor carrying an emergency stop device moves, and the distance between a plurality of emergency stop devices becomes greater than a threshold value. DETAILED DESCRIPTION OF THE INVENTION

[0022] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an emergency stop system, an emergency stop device, and a control method for an emergency stop device for a construction machine according to the present invention will be described with reference to the accompanying drawings. FIG. 1 shows a configuration of an emergency stop system for a construction machine according to an embodiment of the present invention. As shown in Fig. 1, the emergency stop system 1 for construction machinery includes a construction machine 2 that operates automatically within a construction site G, a remote control device 3, and multiple emergency stop devices 5. The emergency stop system 1 for construction machinery of this embodiment stops the automatic operation of the construction machine 2 by transmitting a stop signal via digital wireless from the multiple emergency stop devices 5 when the construction machine 2 is operating automatically.

[0023] The construction machine 2 operates automatically within the construction site G based on a preset operation program (operation scenario), traveling by itself along a set route within the construction site G and performing predetermined work at predetermined locations on the route. As an automatic operation based on a preset operation program, the construction machine 2 may only travel by itself along a set route, or may only perform predetermined work at predetermined locations. Examples of the construction machine 2 include bulldozers, excavators, backhoes, and dump trucks. A plurality of construction machines 2 are deployed within the construction site G. There may be two or more types of construction machines 2 deployed within the construction site G, or a plurality of construction machines 2 of one type may be deployed.

[0024] FIG. 2 is a block diagram showing the functional configuration of the construction machine, the remote control device, and the emergency stop device in the emergency stop system for the construction machine according to this embodiment. As shown in Figure 2, each of the multiple construction machines 2 is equipped with a drive source 22, a construction machine control unit 23, a signal receiving unit 24, a stop control unit 25, a construction machine position information acquisition unit 27, a distance measuring unit 28, and an on-board camera 29.

[0025] The drive source 22 drives each part of the construction machine 2. The drive source 22 drives a traveling mechanism that causes the construction machine 2 to travel, a steering mechanism, a working mechanism for performing various tasks, etc. The drive source 22 is, for example, an engine, a motor, a cylinder, a control valve, etc.

[0026] The construction machine control unit 23 controls the operation of the drive source 22. The construction machine control unit 23 controls the drive source 22 based on a preset operation program, thereby causing the construction machine 2 to operate automatically.

[0027] FIG. 3 is a diagram showing a construction machine equipped with a signal receiving unit capable of receiving stop signals from a plurality of emergency stop devices. The signal receiving unit 24 receives a stop signal from the emergency stop device 5. In this embodiment, the signal receiving unit 24 is capable of receiving stop signals from a plurality of emergency stop devices 5. As will be described later, the plurality of emergency stop devices 5 transmit stop signals to the signal receiving unit 24 of the construction machine 2 by digital radio on mutually different frequency channels. The signal receiving unit 24 is capable of receiving digital radio on each frequency channel of the plurality of emergency stop devices 5. In other words, the signal receiving unit 24 is capable of receiving digital radio signals on mutually different frequency channels. As shown in FIG. 3, in this embodiment, a plurality of signal receiving units 24 are provided corresponding to each of the plurality of emergency stop devices 5 (their frequency channels). That is, in this embodiment, one emergency stop device 5 and one signal receiving unit 24 are provided as a pair. Each of the plurality of signal receiving units 24 is capable of receiving digital wireless signals of one frequency channel. That is, the plurality of signal receiving units 24 are each capable of receiving a different digital wireless frequency channel. By providing a plurality of such signal receiving units 24, the plurality of signal receiving units 24 as a whole are configured to be able to receive digital wireless signals of a plurality of different frequency channels. A plurality of signal receiving units 24 are provided in each construction machine 2.

[0028] The stop control unit 25 stops the driving source 22 when the signal receiving unit 24 receives a stop signal transmitted from at least one of the plurality of emergency stop devices 5. Furthermore, the stop control unit 25 stops the driving source 22 when a communication state confirmation signal periodically transmitted from a signal transmitting unit 52 (described later) of the emergency stop device 5 is not received.

[0029] The construction machine position information acquisition unit 27 acquires position information of the construction machine 2. For example, a GNSS (Global Navigation Satellite System) receiver can be used as the construction machine position information acquisition unit 27. The position information acquired by the construction machine position information acquisition unit 27 is output to the construction machine control unit 23 or the remote operation device 3 as necessary, and is used to determine the self-position of the construction machine 2 in the construction machine control unit 23 or the remote operation device 3.

[0030] The distance measurement unit 28 measures the distance to an object around the construction machine 2. For example, a LiDAR (Light Detection And Ranging) that measures the distance to an object by emitting laser light can be used as the distance measurement unit 28. The distance measurement results by the distance measurement unit 28 are output to the construction machine control unit 23 or the remote operation device 3 and used as necessary.

[0031] The on-board camera 29 captures images of the surroundings from the construction machine 2. The on-board camera 29 outputs, for example, images or videos of the surroundings captured from the driver's seat of the construction machine 2 to, for example, the remote control device 3.

[0032] The remote control device 3 remotely controls the construction machine 2 based on the operation of an operator. The remote control device 3 is installed, for example, in a control room 30 provided outside the construction site G. The remote control device 3 includes, for example, an operation input device 31, an operation device main body 32, a monitor 33, and an operation signal output unit 34.

[0033] The operation input device 31 is a device through which the operator makes operation inputs to remotely operate the construction machine 2, and has buttons, keys, switches, etc. that can be operated by the operator. The operation input device 31 outputs an input signal corresponding to the operation input made to the operation input device 31 to the operation device main body 32. The operation input device 31 is configured to be able to make operation inputs for, for example, setting an operation scenario for automatically operating the construction machine 2 within the construction site G, starting and stopping the automatic operation of the construction machine 2 based on the set operation scenario, remotely manually operating the construction machine 2 when the construction machine 2 is not automatically operated based on the operation scenario, emergency stopping of the construction machine 2, etc.

[0034] The operation device main body 32 outputs operation signals to the construction machine 2 for remotely operating the construction machine 2 based on operation input made to the operation input device 31. The operation device main body 32 is composed of, for example, a personal computer (PC). The operation device main body 32 automatically operates the construction machine 2 to travel within the construction site G along a predetermined route based on a pre-registered operation scenario and perform predetermined operations at predetermined positions on the route. In response to operation input made to the operation input device 31, the operation device main body 32 outputs operation signals to the construction machine 2 for setting an operation scenario, starting and stopping the automatic operation of the construction machine 2 based on the operation scenario, remotely manually operating the construction machine 2 when the construction machine 2 is not automatically operated based on the operation scenario, and performing an emergency stop of the construction machine 2.

[0035] The monitor 33 displays to the operator various information indicating the status of the construction machine 2, including images and videos taken by the on-board camera 29. The operator understands the status of the construction machine 2 based on the various information displayed on the monitor 33, and inputs operations into the operation input device 31 as required.

[0036] The operation signal output unit 34 transmits the operation signal output by the operation device main body 32 to the construction machine 2 wirelessly, such as via Wi-Fi.

[0037] The multiple emergency stop devices 5 are portable. The multiple emergency stop devices 5 are carried by multiple monitors. Each of the multiple monitors carries one emergency stop device 5. Each monitor carries one emergency stop device 5 and visually monitors the multiple construction machines 2 operating automatically within the construction site G. The multiple monitors monitor the multiple construction machines 2 from different positions. The emergency stop device 5 carried by each of the multiple monitors is capable of communicating with the multiple construction machines 2 via digital wireless. Each of the multiple monitors operates the emergency stop device 5 when any of the multiple construction machines 2 they are monitoring reaches a state where an emergency stop is required. When the monitor inputs an operation, the emergency stop device 5 transmits a stop signal via digital wireless to the multiple construction machines 2 within the construction site G, stopping the automatic operation of the multiple construction machines 2.

[0038] FIG. 4 is a diagram showing an example of the appearance of the emergency stop device according to this embodiment. As shown in FIG. 4, each of the multiple emergency stop devices 5 includes, for example, an emergency stop device control unit 50 housed within the housing 5c ​​of the emergency stop device 5, an emergency stop button 101, a power lamp 102, an emergency stop lamp 103, a warning lamp 104, and a setting dial 105.

[0039] An emergency stop button 101, a power lamp 102, an emergency stop lamp 103, a warning lamp 104, and a setting dial 105 are provided on the front surface of the housing 5c. The emergency stop button 101 is pressed by a supervisor when any of the multiple construction machines 2 being monitored reaches a state where an emergency stop is required. When the emergency stop button 101 is pressed by the supervisor, it outputs a stop command to stop the automatic operation of the construction machine 2.

[0040] The power lamp 102 lights up when a power switch (not shown) is ON. The power lamp 102 does not light up when the power switch is OFF, or when the remaining charge of the battery housed in the housing 5c ​​is insufficient (i.e., the battery is dead) even if the power switch is ON.

[0041] The emergency stop lamp 103 lights up when the emergency stop button 101 is pressed.

[0042] As will be described later, the warning lamp 104 lights up when the distance L (see FIG. 3) between the emergency stop device 5 and another emergency stop device 5 becomes equal to or less than a preset threshold value H.

[0043] The setting dial 105 is used to adjust the threshold value H. A display unit 106 that displays the threshold value H that is set by the setting dial 105 is provided on the front surface of the housing 5c.

[0044] As shown in Figure 2, the emergency stop device control unit 50 includes a stop instruction input receiving unit 51, a signal transmitting unit 52, a position information acquiring unit 53, a position information communicating unit 54, a distance determining unit 55, a warning unit 56, and a threshold setting unit 57.

[0045] The stop instruction input receiving unit 51 receives an input of a stop instruction to stop the automatic operation of the construction machine 2, which is output by the emergency stop button 101 when the supervisor operates the emergency stop button 101.

[0046] The signal transmitting unit 52 transmits various signals to the signal receiving unit 24 of the construction machine 2 by digital wireless communication. While the construction machine 2 is operating automatically, the signal transmitting unit 52 periodically transmits a communication status confirmation signal via digital wireless to the signal receiving unit 24 of the construction machine 2 at predetermined fixed time intervals. Furthermore, when the stop instruction input receiving unit 51 receives an input of a stop instruction, the signal transmitting unit 52 transmits a stop signal to the construction machine 2 by digital radio. The signal transmitting unit 52 transmits the stop signal by digital radio on the same frequency channel to the multiple construction machines 2 that are being monitored.

[0047] In this embodiment, communication between the signal transmitting unit 52 of the emergency stop device 5 and the signal receiving unit 24 of the construction machine 2 is realized by digital simplex radio, which does not require the acquisition of a radio operator license or the procedures for opening a radio station, in order to enable quick and easy installation at a construction site. In digital simplex radio, a carrier sense function is implemented to prevent interference between multiple communications in the same frequency band. This function prevents communication if another wireless terminal is using the same frequency channel when transmitting data. In order to avoid communication being disabled due to the carrier sense function as described above and to suppress interference, each of the multiple emergency stop devices 5 is set to use a different frequency channel for the digital simplex radio. However, even if the frequency channels used by each of the multiple emergency stop devices 5 are different as described above, if the distance L between the multiple emergency stop devices 5 is short, radio wave interference may prevent normal communication between the emergency stop device 5 and the construction machine 2. To prevent such a situation, the emergency stop device 5 of this embodiment includes a position information acquisition unit 53, a position information communication unit 54, a distance determination unit 55, and a warning unit 56.

[0048] The position information acquisition unit 53 acquires position information of itself (emergency stop device 5). As the position information acquisition unit 53, for example, a GNSS receiver can be used.

[0049] The position information communication unit 54 communicates wirelessly with other emergency stop devices 5. Here, the wireless communication between the position information communication unit 54 and other emergency stop devices 5 is performed using a different communication method (communication standard) than the communication performed by the signal transmission unit 52. In this embodiment, the position information communication unit 54 performs communication using a communication method such as LTE-M. The position information communication unit 54 transmits to the outside the position information of its own device acquired by the position information acquisition unit 53. More specifically, the position information communication unit 54 transmits the position information of its own device acquired by the position information acquisition unit 53 to another emergency stop device 5. The position information communication unit 54 externally acquires other position information different from the position information of the accident. More specifically, the position information communication unit 54 acquires the position information of the other emergency stop devices 5 transmitted from the other emergency stop devices 5 as the other position information.

[0050] The distance determination unit 55 calculates the distance L between its own position information acquired by the position information acquisition unit 53 and the other position information of the other emergency stop devices 5 acquired by the position information communication unit 54. The distance determination unit 55 targets all other emergency stop devices 5 used at the construction site G and calculates the distance L between its own position information and the other position information of all other emergency stop devices 5. The distance determination unit 55 determines whether the calculated distance L is equal to or less than a preset threshold H. Here, the threshold H of the distance L between its own position information and the other position information is set to be greater than the distance L at which radio wave interference occurs between the emergency stop device 5 and the other emergency stop devices 5. This threshold H can be, for example, 10 to 20 m.

[0051] When the distance L between its own position information and the other position information is equal to or less than the threshold H, the warning unit 56 turns on the warning lamp 104 to warn the supervisor that radio wave interference may cause normal communication between the emergency stop device 5 and the construction machine 2, making it impossible to send a stop signal to the construction machine 2. The supervisor who recognizes the warning from the warning unit 56 (warning lamp 104) visually checks the positions of other supervisors carrying emergency stop devices 5 in the vicinity, and moves so that the distance L to the other emergency stop devices 5 is equal to or greater than the threshold H. This prevents radio wave interference from making it impossible to send a stop signal to the construction machine 2.

[0052] The threshold setting unit 57 can arbitrarily set a threshold H for the distance L between its own location information and other location information by operating the setting dial 105. Since the distance at which radio wave interference can occur varies depending on the frequency channel of the digital radio (digital simplex radio) used by the emergency stop device 5, the threshold setting unit 57 can adjust the threshold H as appropriate depending on the frequency channel used.

[0053] In such an emergency stop system 1 for construction machinery, automatic operation of a plurality of construction machines 2 within a construction site G is started by remote control of a remote control device 3. When automatic operation of a plurality of construction machines 2 within a construction site G is started by remote control of a remote control device 3, a plurality of monitors each activate an emergency stop device 5 that they carry with them. When the emergency stop device 5 is activated, a signal transmitting unit 52 establishes communication with a signal receiving unit 24 of the construction machine 2 via digital radio (digital simplex radio).

[0054] While the construction machine 2 is operating automatically, an operator of the remote control device 3 and multiple observers carrying multiple emergency stop devices 5 monitor the operating status of the construction machine 2. When the operator of the remote control device 3 determines that an emergency stop of the construction machine 2 is necessary, the operator performs a predetermined operation to bring the construction machine 2 to an emergency stop using the operation input device 31. In response to this, the operation device main body 32 outputs an operation signal to bring the construction machine 2 to an emergency stop via the operation signal output unit 34, based on the operation input made to the operation input device 31. Furthermore, when a monitor carrying the emergency stop device 5 determines that an emergency stop of the construction machine 2 is necessary, the monitor presses the emergency stop button 101 of the emergency stop device 5 that is connected to communication with the construction machine 2. Then, the stop instruction input receiving unit 51 of the emergency stop device 5 receives the input of a stop instruction to stop the automatic operation of the construction machine 2, and the signal transmitting unit 52 transmits a stop signal via digital wireless to the multiple construction machines 2 that are being monitored. When the signal receiving unit 24 of the construction machine 2 receives an operation signal from the remote control device 3 to emergency stop the construction machine 2, or a stop signal from one of the multiple emergency stop devices 5, the stop control unit 25 of the construction machine 2 stops the drive source 22 and stops the automatic operation of the construction machine 2.

[0055] Furthermore, while the construction machine 2 is operating automatically, the signal transmitting unit 52 periodically transmits a communication status confirmation signal to the signal receiving unit 24 of the construction machine 2 at predetermined fixed time intervals. In each construction machine 2, if the communication status confirmation signal, which is periodically transmitted from the signal transmitting unit 52 of the emergency stop device 5 to the signal receiving unit 24, is not received for a predetermined period of time or longer, the stop control unit 25 stops the drive source 22. As a result, if the periodic transmission of the communication status confirmation signal is interrupted due to a low remaining battery charge in the emergency stop device 5, poor communication via digital wireless between the emergency stop device 5 and the construction machine 2, a malfunction of the emergency stop device 5, or the like, the automatic operation of the construction machine 2 is stopped. This configuration prevents the occurrence of a situation in which, despite a supervisor wanting to press the emergency stop button 101 of the emergency stop device 5 to stop the automatic operation of the construction machine 2, he or she is unable to stop the automatic operation of the construction machine 2 due to a lack of communication between the emergency stop device 5 and the construction machine 2.

[0056] FIG. 5 is a flowchart showing the flow of the control method for the emergency stop device in this embodiment. The method for controlling the emergency stop devices includes step S11 of connecting to the construction machine, step S12 of acquiring its own position information, step S13 of transmitting its own position information and acquiring other position information, step S14 of calculating the distance between its own position information and the other position information, step S15 of determining whether the distance between its own position information and the other position information is equal to or less than a threshold, and step S16 of issuing a warning. These steps S11 to S16 are executed in each of the multiple emergency stop devices 5 while the construction machine 2 is automatically operating.

[0057] As described above, when automatic operation of the construction machine 2 is carried out, the emergency stop device 5 is activated and connected to the construction machine 2 (step S11), and the emergency stop device control unit 50 of the emergency stop device 5 executes the processing from step S12 onwards at preset time intervals (for example, every second). In step S12, the position information acquisition unit 53 of each of the plurality of emergency stop devices 5 acquires its own position information.

[0058] Also, in step S13, in each of the multiple emergency stop devices 5, the location information communication unit 54 communicates wirelessly with the other emergency stop devices 5, transmits its own location information to the other emergency stop devices 5, and obtains the location information of the other emergency stop devices 5 as other location information.

[0059] Next, in step S14, the distance determination unit 55 calculates the distance L between the emergency stop device 5's own position information acquired in step S12 and the other position information of the other emergency stop device 5 acquired in step S13. Subsequently, in step S15, the distance determination unit 55 determines whether the distance L between the own position information and the other position information calculated in step S14 is equal to or less than a preset threshold value H.

[0060] FIG. 6 is a diagram illustrating a state in which the distance between a plurality of emergency stop devices is greater than a threshold value. As a result, for example, as shown in Fig. 6, if the distance L between the own position information of the emergency stop device 5 carried by the monitor and the other position information of the other emergency stop device 5 carried by the other monitor is greater than the preset threshold H (No in step S15), it means that there is a sufficient distance L between the own emergency stop device 5 and the other emergency stop device 5 so that radio wave interference does not occur. In this case, the process transitions to step S12, and the above process is repeated. In this case, the monitor continues monitoring the construction machine 2 as is.

[0061] FIG. 7 is a diagram showing a state in which the distance between a plurality of emergency stop devices is equal to or less than a threshold value. 7, if in step S15 the distance L between the own position information and the other position information is equal to or less than the preset threshold H (Yes in step S15), in step S16 the warning unit 56 turns on the warning lamp 104 (see FIG. 4). This warns the monitor that there is a possibility that radio wave interference may prevent the transmission of a stop signal to the construction machine 2.

[0062] FIG. 8 is a diagram showing a state in which, from the state shown in FIG. 7, a monitor carrying an emergency stop device moves and the distance between the plurality of emergency stop devices becomes greater than the threshold value. The monitor, who has recognized the warning from the warning unit 56 (warning lamp 104), visually checks the positions of other monitors carrying emergency stop devices 5 in the vicinity, and moves so that the distance L to the other emergency stop devices 5 is equal to or greater than the threshold H, as shown in FIG. 8. After moving, when the processing from step S12 onwards is next repeated, in step S15, the distance L between the monitor's own position information and the other position information becomes greater than the preset threshold H, so the processing transitions to step S12 instead of step S16, and the warning lamp 104 is turned off instead of turned on. In other words, the monitor can confirm that the distance L to the other emergency stop devices 5 is equal to or greater than the threshold H by the warning lamp 104 transitioning from the on state to the off state.

[0063] The emergency stop system 1 for construction machinery as described above is a system for emergency stop for construction machinery comprising a construction machine 2 that operates automatically within a construction site G, and a plurality of portable emergency stop devices 5 that transmit stop signals to the construction machine 2 by digital wireless to stop the automatic operation of the construction machine 2, wherein the construction machine 2 comprises a drive source 22, a construction machine control unit 23 that controls the drive source 22 to operate the construction machine 2 automatically, a signal receiving unit 24 that receives stop signals from the plurality of emergency stop devices 5, and a stop control unit 25 that stops the drive source 22 when a stop signal is received, and each of the plurality of emergency stop devices 5 receives a stop instruction to stop the automatic operation of the construction machine 2. a signal transmitting unit 52 that transmits a stop signal to the construction machine 2 by digital radio when it receives the input of a stop command; a position information acquiring unit 53 that acquires its own position information; a position information communicating unit 54 that communicates with other emergency stop devices 5 by radio and transmits its own position information to the other emergency stop devices 5 and acquires the position information of the other emergency stop devices 5 as other position information; a distance determining unit 55 that calculates the distance L between its own position information and the other position information and determines whether the distance L is equal to or less than a threshold value H; and a warning unit 56 that warns that it will not be possible to transmit a stop signal to the construction machine 2 if the distance L is equal to or less than the threshold value H.

[0064] According to the above-described configuration, the emergency stop system 1 for construction machinery includes a construction machine 2 that operates automatically within a construction site G, and multiple portable emergency stop devices 5 that transmit stop signals to the construction machine 2 via digital wireless communication to stop the automatic operation of the construction machine 2. The construction machine 2 is operated automatically by a construction machine control unit 23 controlling the drive source 22. The emergency stop devices 5 can be carried by a supervisor or the like who monitors the construction machine 2. If the construction machine 2 malfunctions, the supervisor who confirms the malfunction inputs a stop command to the emergency stop device 5 to stop the automatic operation of the construction machine 2. When the stop command input receiving unit 51 receives the input of this stop command, the signal transmitting unit 52 transmits a stop signal to the construction machine 2 via digital wireless communication. On the construction machine 2 side, the signal receiving unit 24 receives the transmitted stop signal, and the stop control unit 25 stops the drive source 22. In this way, the supervisor or the like can use the emergency stop devices 5 to stop the automatically operating construction machine 2. Here, when multiple emergency stop devices 5 transmitting by digital wireless are close to each other, radio wave interference between the emergency stop devices 5 may prevent communication between the emergency stop devices 5 and the construction machine 2. In such a case, if a mechanism is provided that transmits and receives a communication status confirmation signal between the emergency stop devices 5 and the construction machine 2, as described in this embodiment, and that stops the automatic operation of the construction machine 2 when the communication status confirmation signal is not received by the construction machine 2 and communication is impossible, the construction machine 2 may stop even when it is not desired to stop the automatic operation of the construction machine 2, which may reduce the processing efficiency of the construction machine 2. In contrast, in the above-described configuration, each of the multiple emergency stop devices 5 includes a location information acquisition unit 53 that acquires its own location information, a location information communication unit 54 that wirelessly communicates with the other emergency stop devices 5, transmits its own location information to the other emergency stop devices 5, and acquires the location information of the other emergency stop devices 5 as the other location information, a distance determination unit 55 that calculates the distance L between its own location information and the other location information and determines whether the distance L is equal to or less than a threshold H, and a warning unit 56 that warns that a stop signal cannot be transmitted to the construction machine 2 if the distance L is equal to or less than the threshold H. With this configuration, if observers, etc. get too close to each other and the distance between the emergency stop devices 5 becomes equal to or less than the threshold, the warning unit 56 of the emergency stop device 5 warns that a stop signal cannot be transmitted to the construction machine 2. Based on this warning, observers, etc. can confirm that they are approaching other observers, etc. In this case, an observer, etc. who is moving, can increase the distance L between himself, etc., by moving in the opposite direction. Alternatively, a monitor who has confirmed that another monitor is approaching can move in the same direction as the other monitor who is moving, thereby preventing further proximity between the monitors. In this way, it is possible to avoid close proximity between monitors, i.e., between emergency stop devices 5, thereby preventing the emergency stop devices 5 from coming close to each other and causing radio wave interference that makes it impossible to communicate between the emergency stop devices 5 and the construction machine 2.

[0065] Furthermore, while the construction machine 2 is operating automatically, a communication status confirmation signal is transmitted from the signal transmitting unit 52 of each of the multiple emergency stop devices 5 to the signal receiving unit 24 of the construction machine 2 at regular time intervals, and the stop control unit 25 stops the drive source 22 if the communication status confirmation signal is not received.

[0066] For example, due to a malfunction of the emergency stop device 5 or a low remaining battery charge of the emergency stop device 5, communication from the signal transmitting unit 52 of the emergency stop device 5 to the signal receiving unit 24 of the construction machine 2 may become impossible. In such a case, even if a supervisor or the like wants to stop the automatic operation of the construction machine 2, the automatic operation of the construction machine 2 cannot be stopped because communication from the emergency stop device 5 to the construction machine 2 is not possible, and the construction machine 2 will continue to operate automatically. In contrast, in the above configuration, while the construction machine 2 is operating automatically, a communication status confirmation signal is transmitted from the signal transmitting unit 52 of each of the multiple emergency stop devices 5 to the signal receiving unit 24 of the construction machine 2 at regular time intervals. Furthermore, on the construction machine 2 side, the stop control unit 25 stops the drive source 22 when the communication status confirmation signal is not received. Therefore, if communication from the signal transmitting unit 52 of the emergency stop device 5 becomes impossible, the construction machine 2 will no longer be able to receive the communication status confirmation signal, and the stop control unit 25 will stop the drive source 22 of the construction machine 2, thereby stopping the automatic operation of the construction machine 2. In this way, the automatic operation of the construction machine 2 is automatically stopped when communication is lost, which prevents the construction machine 2 from continuing to operate automatically, even though a supervisor or the like wants to stop the automatic operation of the construction machine 2, due to a lack of communication between the emergency stop device 5 and the construction machine 2.

[0067] Each of the emergency stop devices 5 includes a threshold value setting unit 57 that can set the threshold value H.

[0068] With this configuration, the threshold setting unit 57 can appropriately set the threshold H of the distance L between its own position information and other position information for each of the multiple emergency stop devices 5, which warns that it will no longer be able to transmit a stop signal to the construction machine 2, depending on the type of digital radio used, the number and placement of monitors carrying multiple emergency stop devices 5, etc.

[0069] The emergency stop device 5 as described above is configured to be portable and transmits a stop signal via digital wireless to construction machinery 2 operating automatically within a construction site G, thereby stopping the automatic operation of the construction machinery 2. The emergency stop device 5 includes a stop instruction input receiving unit 51 that receives input of a stop instruction to stop the automatic operation of the construction machinery 2, a signal transmitting unit 52 that transmits a stop signal via digital wireless to the construction machinery 2 when input of a stop instruction is received, a location information acquiring unit 53 that acquires its own location information, a location information communication unit 54 that communicates wirelessly with the outside (other emergency stop devices 5) and transmits its own location information to the outside (other emergency stop devices 5) and acquires other location information (location information of the other emergency stop devices 5) that is different from its own location information from the outside (other emergency stop devices 5), a distance determination unit 55 that calculates the distance L between its own location information and the other location information and determines whether the distance L is equal to or less than a threshold H, and a warning unit 56 that warns that it will not be able to transmit a stop signal to the construction machinery 2 if the distance L is equal to or less than the threshold H.

[0070] According to the above configuration, the emergency stop device 5 is configured to be portable, and transmits a stop signal to the construction machine 2 by digital wireless communication to stop the automatic operation of the construction machine 2. Such an emergency stop device 5 can be carried by a monitor or the like who monitors the construction machine 2. If the construction machine 2 malfunctions, the monitor who confirms the malfunction inputs a stop command to the emergency stop device 5 to stop the automatic operation of the construction machine 2. When the stop command input receiving unit 51 receives the input of this stop command, the signal transmitting unit 52 transmits a stop signal to the construction machine 2 by digital wireless communication. On the construction machine 2 side, reception of the transmitted stop signal can be used as a trigger to stop the automatic operation. Incidentally, in the case where multiple monitors are mobilized at a construction site G and each of the multiple monitors carries an emergency stop device 5, if a monitor moves and approaches other monitors as the construction machinery 2 moves, for example, the multiple emergency stop devices 5 may come into close proximity to each other, and radio wave interference between the emergency stop devices 5 may prevent communication from the emergency stop devices 5 to the construction machinery 2. In contrast, in the above configuration, the emergency stop device 5 is configured to include a location information acquisition unit 53 that acquires its own location information, a location information communication unit 54 that wirelessly communicates with the outside, transmits its own location information to the outside, and acquires other location information different from its own location information from the outside, a distance determination unit 55 that calculates the distance L between its own location information and the other location information and determines whether the distance L is equal to or less than a threshold H, and a warning unit 56 that warns that it will not be possible to transmit a stop signal to the construction machine 2 if the distance L is equal to or less than the threshold H. Therefore, in a case where multiple monitors each carry multiple emergency stop devices 5, each emergency stop device 5 can communicate with nearby other emergency stop devices 5 as the outside, transmit its own location information to the other emergency stop devices 5, and acquire other location information from the other emergency stop devices 5 as the location information of the other emergency stop devices 5. In this case, if the observers get too close to each other and the distance L between the emergency stop devices 5 falls below the threshold H, the warning unit 56 of the emergency stop device 5 warns that it will no longer be possible to send a stop signal to the construction machine 2. Based on this warning, the observer can confirm that he or she is approaching another observer. In this case, the observer who is moving can increase the distance L between himself or herself and the other observer by turning around and moving in the opposite direction. Alternatively, an observer who confirms that another observer is approaching can move in the same direction as the other observer to avoid further approach between the observers. In this way, it is possible to avoid close proximity between monitors, i.e., between emergency stop devices 5, thereby preventing the emergency stop devices 5 from coming close to each other and causing radio wave interference that makes it impossible to communicate between the emergency stop devices 5 and the construction machine 2.

[0071] Furthermore, the above-described method for controlling an emergency stop device is a method for controlling an emergency stop device when a plurality of emergency stop devices 5 are used, each of which is configured to be portable and which transmits a stop signal via digital wireless to a construction machine 2 operating automatically within a construction site G to stop the automatic operation of the construction machine 2, and includes the following steps: step S12, in which each of the plurality of emergency stop devices 5 acquires its own position information; step S13, in which each of the plurality of emergency stop devices 5 communicates wirelessly with the other emergency stop devices 5 and transmits its own position information to the other emergency stop devices 5, and acquires the position information of the other emergency stop devices 5 as the other position information; steps S14 and S15, in which each of the plurality of emergency stop devices 5 calculates the distance L between its own position information and the other position information, and determines whether the distance L is equal to or less than a threshold value H; and step S16, in which each of the plurality of emergency stop devices 5 issues a warning that it will not be able to transmit a stop signal to the construction machine 2 if the distance L is equal to or less than the threshold value H.

[0072] With this configuration, when multiple portable emergency stop devices 5 are used, which transmit stop signals by digital radio to construction machines 2 operating automatically within a construction site G to stop the automatic operation of the construction machines 2, it is possible to prevent the monitors, i.e., the emergency stop devices 5, from coming too close to each other. This prevents the emergency stop devices 5 from coming too close to each other, which would cause radio wave interference and prevent communication between the emergency stop devices 5 and the construction machines 2.

[0073] (Modification of the embodiment) The emergency stop system, emergency stop device, and control method for the emergency stop device for a construction machine of the present invention are not limited to the above-described embodiments explained with reference to the drawings, and various modifications are possible within the technical scope. For example, in the above embodiment, while the construction machine 2 is operating automatically, a communication status confirmation signal is transmitted from the signal transmitting unit 52 of each of the multiple emergency stop devices 5 to the signal receiving unit 24 of the construction machine 2 at regular time intervals, and the stop control unit 25 stops the drive source 22 if the communication status confirmation signal is not received, but this is not limited to this. In other words, the emergency stop system for construction machinery may be configured in such a way that the above-described transmission and reception of a communication status confirmation signal between the emergency stop device 5 and the construction machinery 2 is not performed, and the automatic operation of the construction machinery 2 is not stopped when the communication status confirmation signal is not received by the construction machinery 2 and communication is not possible.

[0074] When using such a configuration, for example, if two monitors, i.e., two emergency stop devices 5, come close to each other and radio wave interference prevents communication from the signal transmitting unit 52 of the emergency stop device 5 to the signal receiving unit 24 of the construction machine 2, even if the monitor or other person wants to stop the automatic operation of the construction machine 2, they will not be able to stop the automatic operation of the construction machine 2 because they cannot communicate from the emergency stop device 5 to the construction machine 2, and the construction machine 2 will continue to operate automatically. In contrast, by configuring the emergency stop device 5 to have the position information acquisition unit 53, position information communication unit 54, distance determination unit 55, and warning unit 56 as in the above embodiment, it is possible to prevent close proximity between monitors, i.e., between emergency stop devices 5. This prevents the emergency stop devices 5 from coming close to each other, causing radio wave interference that disables communication between the emergency stop device 5 and the construction machine 2, resulting in the construction machine 2 continuing to operate automatically even if an attempt is made to stop the automatic operation of the construction machine 2.

[0075] However, while the configuration of this modified example can prevent communication between the emergency stop device 5 and the construction machine 2 from being disabled due to radio wave interference, it cannot prevent communication between the emergency stop device 5 and the construction machine 2 from being disabled due to a battery failure or insufficient charge in the emergency stop device 5. Therefore, if the battery is low on charge or has a malfunction, the automatic operation of the construction machine 2 cannot be stopped, and the construction machine 2 will continue to operate automatically. For this reason, it goes without saying that it is more desirable to configure the emergency stop system for construction machinery to send and receive a communication status confirmation signal, as in the above embodiment.

[0076] Furthermore, in the above embodiment, the warning unit 56 turns on the warning lamp 104 when the distance L between its own position information and the other position information is equal to or less than the threshold H, thereby warning the supervisor that radio wave interference will prevent transmission of a stop signal to the construction machine 2, but this is not limited to this. The warning unit 56 may also issue a warning by sounding a buzzer, playing a voice message, emitting vibrations using a vibrator built into the emergency stop device 5, displaying a text message, or other means.

[0077] In the above embodiment, the threshold value H is set by the threshold value setting unit 57, but this is not limiting. For example, the threshold value H may be automatically calculated and set by the emergency stop device control unit 50 based on the frequency channels of the digital radio used by the emergency stop device 5 and other emergency stop devices 5.

[0078] Furthermore, in the above embodiment, each construction machine 2 is provided with a plurality of signal receiving units 24 so that digital wireless signals of a plurality of different frequency channels can be received from a plurality of emergency stop devices 5, but this is not limited to this. For example, each construction machine 2 may be provided with a single signal receiving unit 24 having a plurality of receiving circuits so that digital wireless signals of a plurality of different frequency channels can be received.

[0079] In the above embodiment, the signal transmitting unit 52 of the emergency stop device 5 communicates by digital simplex radio as digital radio, but other digital radio communication methods may be used.

[0080] Furthermore, in the above embodiment, a situation has been described in which a plurality of monitors or the like monitor a plurality of construction machines 2, but this is not limiting. The above emergency stop system 1 may also be used in a situation in which a plurality of monitors simultaneously monitor one construction machine 2.

[0081] In the above embodiment, as shown in Figs. 1 and 3, for example, the monitor etc. is described as carrying the emergency stop device 5 and monitoring the construction machine 2 at a position outside the construction site G, but this is not limited to this. The monitor etc. may also carry the emergency stop device 5 at a position inside the construction site G and monitor the construction machine 2. The monitor etc. may be located anywhere as long as the signal transmitting unit 52 of the emergency stop device 5 that the monitor etc. carries and the signal receiving unit 24 of the construction machine 2 can communicate by digital wireless.

[0082] In the above embodiment, the signal receiving unit 24 that receives stop signals from multiple emergency stop devices 5 and the stop control unit 25 that stops the drive source when a stop signal is received have been described as being provided only in the automatically operating construction machine 2, but this is not limited to this. For example, if a construction machine operated by a construction worker is also provided at the construction site G in addition to the automatically operating construction machine 2 and performs construction work together with the automatically operating construction machine 2, the construction machine operated by the construction worker may also be provided with a signal receiving unit that receives stop signals from multiple emergency stop devices 5 and a stop control unit that stops the drive source when a stop signal is received, just like the automatically operating construction machine 2. In this case, when a supervisor or the like stops the automatically operating construction machine 2 using the emergency stop device 5 provided corresponding to the automatically operating construction machine 2, the operation of the construction machine operated by the construction worker may also be stopped at the same time. Alternatively, an emergency stop device may be provided separately and independently from the emergency stop device 5 provided corresponding to the automatically operating construction machine 2 to stop the operation of the construction machine operated by the construction worker.

[0083] In addition, the configurations given in the above embodiments can be selected or changed as appropriate without departing from the spirit of the present invention. [Explanation of symbols]

[0084] 1 Emergency stop system 2. Construction machinery 5 Emergency stop device 22 Power Source 23 Construction machinery control unit 24 Signal receiving unit 25 Stop control section 51 Stop instruction input reception unit 52 Signal transmitter 53 Location information acquisition unit 54 Location Information Communication Department 55 Distance determination unit 56 Warning section 57 Threshold setting unit

Claims

1. An emergency stop system for construction machinery, comprising: a construction machinery that operates automatically within a construction site; and a plurality of portable emergency stop devices that transmit a stop signal to the construction machinery by digital radio to stop the automatic operation of the construction machinery; The construction machine is A driving source; a construction machine control unit that controls the drive source to automatically operate the construction machine; a signal receiving unit that receives the stop signals from the plurality of emergency stop devices; a stop control unit that stops the drive source when the stop signal is received; Equipped with Each of the plurality of emergency stop devices is a stop instruction input receiving unit that receives an input of a stop instruction to stop the automatic operation of the construction machine; a signal transmitting unit that transmits the stop signal to the construction machine by digital wireless when the input of the stop instruction is received; a location information acquisition unit that acquires its own location information; a position information communication unit that wirelessly communicates with the other emergency stop devices, transmits the position information of the own device to the other emergency stop devices, and acquires position information of the other emergency stop devices as other position information; a distance determination unit that calculates a distance between the own location information and the other location information and determines whether the distance is equal to or less than a threshold; a warning unit that warns that the stop signal cannot be transmitted to the construction machine when the distance is equal to or less than the threshold value; An emergency stop system for construction machinery, comprising:

2. While the construction machine is automatically operating, a communication status confirmation signal is transmitted from the signal transmitting unit of each of the plurality of emergency stop devices to the signal receiving unit of the construction machine at regular time intervals, The stop control unit stops the driving source when the communication state confirmation signal is not received.

2. The emergency stop system for a construction machine according to claim 1.

3. Each of the plurality of emergency stop devices includes a threshold setting unit that can set the threshold.

3. An emergency stop system for a construction machine according to claim 1 or 2.

4. An emergency stop device that is portable and transmits a stop signal via digital radio to a construction machine that is automatically operating at a construction site to stop the automatic operation of the construction machine, a stop instruction input receiving unit that receives an input of a stop instruction to stop the automatic operation of the construction machine; a signal transmitting unit that transmits the stop signal to the construction machine by digital wireless when the input of the stop instruction is received; a location information acquisition unit that acquires its own location information; a location information communication unit that wirelessly communicates with an external device, transmits the location information of the device to the external device, and acquires other location information from the external device that is different from the location information of the device; a distance determination unit that calculates a distance between the own location information and the other location information and determines whether the distance is equal to or less than a threshold; a warning unit that warns that the stop signal cannot be transmitted to the construction machine when the distance is equal to or less than the threshold value; An emergency stop device comprising:

5. A threshold setting unit is provided that can set the threshold.

5. The emergency stop device according to claim 4.

6. A method for controlling an emergency stop device when a plurality of portable emergency stop devices are used, the emergency stop devices being configured to transmit a stop signal by digital radio to a construction machine operating automatically at a construction site to stop the automatic operation of the construction machine, acquiring position information of each of the plurality of emergency stop devices; a step in which each of the plurality of emergency stop devices wirelessly communicates with the other emergency stop devices, transmits its own position information to the other emergency stop devices, and acquires position information of the other emergency stop devices as other position information; a step of calculating a distance between the position information of the emergency stop device itself and the other position information in each of the plurality of emergency stop devices, and determining whether the distance is equal to or less than a threshold; a step of issuing a warning in each of the plurality of emergency stop devices that the stop signal cannot be transmitted to the construction machine when the distance is equal to or less than the threshold value; 1. A control method for an emergency stop system of a construction machine, comprising:

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