JP2023022551A - Anti-theft system for construction machine - Google Patents

Abstract

To provide an anti-theft system for a construction machine, which safely uses a password for activating an engine starter of the construction machine by a simple method without losing convenience, and the construction machine.SOLUTION: The anti-theft system for the construction machine comprises: a control unit that can operate an engine of the construction machine with a condition that a password stored in a storage unit is input; changing means for changing the stored password; a management unit that automatically stores the password changed by changing means different from the storage unit; and a display terminal that displays the password stored in a management device through authentication by specifying means for specifying an individual.SELECTED DRAWING: Figure 2

Description

The present invention relates to an anti-theft system for construction machinery.

2. Description of the Related Art An anti-theft device for construction machinery is generally known that allows rewriting of a password (personal identification number) that enables starting of an engine starter. (See Patent Document 1)

Such anti-theft devices for construction machines prevent theft of construction machines by rewriting passwords stored in the construction machines at any time.

JP-A-2004-58720

However, at construction sites, there are cases where one construction machine is used by multiple workers, and each worker arbitrarily changes the password for starting the engine starter, and the password currently stored in the construction machine is lost. may be unknown.

In addition, even if one construction machine is used by a specific worker, if the worker frequently changes the password, the worker may forget the last changed password. Remembered passwords may become unknown.

Moreover, in a certain situation, frequent changes of the password of the construction machine during operation of the construction machine not only make it difficult to remember the changed password, but also make it difficult to operate the machine by mistake while changing the password. The construction machine may move unexpectedly due to contact with the lever.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems of the prior art, and provides a construction machine theft prevention system that can safely operate a password for starting an engine starter of a construction machine by a simple method without hindering convenience. intended to provide.

In order to solve the above-described problems, the present invention provides a control unit that enables an engine of a construction machine to operate on condition that a password stored in a storage unit is entered, and a password stored in the storage unit that is changed. a management unit for automatically storing the changed password changed by the changing means; and a display terminal for displaying the changed password stored in the management device by authentication by means for identifying an individual. , and an anti-theft system for construction equipment.

The invention according to another aspect of the present invention includes a communication unit that transmits the change password to the management unit installed outside the construction machine, and the construction machine includes the storage unit, the control unit, The anti-theft system for the construction machine includes the changing means and the communication unit.

The invention according to another aspect of the present invention is the construction machine anti-theft system, wherein the specifying means includes first specifying means for causing the management unit to authenticate, and second specifying means for causing the display terminal to authenticate. consists of

The invention according to another aspect of the present invention comprises the anti-theft system for the construction machine, wherein the first identifying means is another password, and the display terminal can store the other password.

The invention according to another aspect of the present invention comprises the construction machine anti-theft system, wherein the second identification means is at least biometric authentication.

According to another aspect of the present invention, the construction machine has a cut-off lever that enables or disables an operating device that operates the construction machine, and the changing means is configured to: and a theft system for the construction machine that permits the password to be changed when the operating device is disabled.

The invention according to another aspect of the present invention provides a control unit that makes an engine operable on condition that a password stored in a storage unit is entered, and change means that changes the password stored in the storage unit. and, wherein the construction machine has a cut-off lever for enabling or disabling an operation device for operating the construction machine, and the change means is configured by the cut-off lever to cause the The construction machine is characterized by permitting a change of the password when the operating device is invalid.

According to the present invention, a password for starting an engine starter of a construction machine can be safely operated by a simple method without impairing convenience.

1 is a side view of a hydraulic excavator equipped with an anti-theft system for construction machinery according to an embodiment of the present invention; FIG. 1 is a schematic diagram showing a schematic configuration of an anti-theft system for construction machinery according to an embodiment of the present invention; FIG. 1 is a front view of a monitor of an anti-theft system for construction machinery according to one embodiment of the present invention; FIG. 1 is a front view of a monitor displaying a password input screen of the anti-theft system for construction machinery according to one embodiment of the present invention; FIG. 1 is a front view of a monitor displaying a state in which a part of a password is entered on a password entry screen of the anti-theft system for construction machinery according to one embodiment of the present invention; FIG. 1 is a front view of a monitor displaying a home screen of an anti-theft system for construction machinery according to an embodiment of the present invention; FIG. 1 is a front view of a monitor displaying a menu screen of an anti-theft system for construction machinery according to one embodiment of the present invention; FIG. 1 is a front view of a monitor displaying a password change screen of the anti-theft system for construction machinery according to one embodiment of the present invention; FIG. FIG. 2 is a front view of a monitor displaying a state in which a part of a password is entered on a password setting change screen of the anti-theft system for construction machinery according to one embodiment of the present invention; 1 is a front view of a monitor displaying a password change completion notification screen of the anti-theft system for construction machinery according to one embodiment of the present invention; FIG. 1 is a front view of a mobile terminal of an anti-theft system for construction machinery according to an embodiment of the present invention; FIG. 1 is a front view of a mobile terminal displaying an unlock screen of an anti-theft system for construction machinery according to an embodiment of the present invention; FIG. 1 is a front view of a mobile terminal displaying a login screen to an external server using an application of the anti-theft system for construction machinery according to one embodiment of the present invention; FIG. FIG. 2 is a front view of a mobile terminal displaying an information selection screen for selecting necessary hydraulic excavator information from an external server using an application of the construction machine anti-theft system according to one embodiment of the present invention. 1 is a front view of a mobile terminal displaying an information display screen including information stored in an external server using an application of the anti-theft system for construction machinery according to one embodiment of the present invention; FIG.

1 and 2, a hydraulic excavator 100 as a representative example of a construction machine to which the present invention is applied will be described in detail below.

The hydraulic excavator 100 includes a self-propelled lower traveling body 200, an upper revolving body 300 rotatably supported on the lower traveling body 200, and a working device 400 rotatably supported in front of the upper revolving body 300. and constitutes a part of the construction machine theft system 500 .

The lower traveling body 200 has a center frame (not shown) and side frames 210 (only one side is shown) that form a pair symmetrically with the center frame and extend in the front-rear direction. A drive wheel 211 (only one side is shown) driven by a traveling motor (not shown) is installed in , and a plurality of idler wheels 212 (only one side is shown) are arranged toward one front end. A crawler belt 213 (only one side of which is shown) is wound around the driving wheel 211 and the idler wheel 212, and a soil removing device 220 is mounted in front of the center frame.

The upper rotating body 300 is rotated by a rotating motor (not shown) via a rotating bearing (not shown). An operator's seat 310 is arranged above the upper rotating body. , an engine room 340 composed of a seat mount 320 and a bonnet 330 is arranged behind the upper revolving body. In the engine room 340, in addition to an engine (not shown), a communication device 514 for transmitting a password for starting the engine starter to an external server 530 is arranged. (not shown) drives the working device 400, the undercarriage 200, and the swing motor by an actuator through a control valve (not shown) that controls the flow rate and direction of oil.

The work device 400 includes a swing post 410 supported to rotate horizontally at the tip of the upper swing body 300 , a boom 420 supported on the swing post 410 so as to rotate vertically, and a tip of the boom 420 . and a bucket 4450 rotatably attached to the tip of the arm 430. The bucket 4450 is installed below the upper rotating body 300 to rotate the swing post 410 in the horizontal direction. A swing cylinder (not shown), a boom cylinder 421 installed below the boom 420 to move the boom 420, an arm cylinder 431 installed above the boom 420 to move the arm 430, and an arm cylinder 431 installed above the arm 430 and a bucket cylinder 451 that moves a bucket 450 via a bucket link 440 .

The operator's seat 310 includes a seat 311, and a pair of left and right travel levers 312a and 312b (only one side is shown) which are located in front of the seat 311 and are erected from the floor surface of the operator's seat 310 for performing travel operation, Between the seat 311 and the travel lever 312a is an exit 313 through which an operator can get on and off from the operator's seat 310, and a pair of left and right side levers 312c installed on both sides of the seat 311 for operating and turning the work device 400. , 312d (only one side is shown), a cut-off lever 312e projecting from below the console of the side lever 312c on one side so as to block passage of the exit 313, and the side lever 312d on the other side. and a monitor 314 for displaying the settings of a plurality of functions of the hydraulic excavator and the state quantities of the hydraulic excavator.

By pulling up the cut-off lever 312e, the side lever 312c is rotated upward to make the exit port 313 passable, and the pilot pressure for controlling the control valve is shut off to put the hydraulic excavator 100 in an inoperable state. do.

Next, with reference to FIG. 2, a schematic configuration of the construction machine theft system 500 will be described.

The anti-theft system 500 includes an in-vehicle network 510 built in the hydraulic excavator 100 , an external server 530 connected to the in-vehicle network 510 via a data communication network 520 , and an external server 530 and data communication network 520 . It is composed of a mobile terminal 540 connected to the network.

The in-vehicle network 510 has an engine ECU 511 that starts the engine starter after turning the key to the start position on the condition that the password input to the monitor 314 matches the stored password after turning the key to the accessory position. In addition to transmitting the password input to the monitor 314 to the engine ECU 511, the engine E issues a command to change the password stored in the engine ECU 511 to a password newly input to the monitor 314.
A monitor ECU 512 in a monitor 314 that transmits to the CU 511; A communication device 514 that transmits the password to the outside of the in-vehicle network 510 via a data communication network 520 . The password may be stored only in the integrated ECU 513. In that case, when the password input to the monitor 314 matches the password stored in the integrated ECU 513, the integrated ECU 513 outputs a start permission command to the engine ECU 511, and the engine starts. The engine starter can be activated after turning the key to the start position.

The communication means of the engine ECU 511, the monitor ECU 512, the integrated ECU 513, and the ECU of the communication device of the in-vehicle network 510 is CAN (Controller Area Network), but is not limited to this.

The engine ECU 511, the monitor ECU 512, the integrated ECU 513, and the communication device ECU are connected to a 12-volt battery installed in the machine, and are controlled by a power supply that supplies stable voltage to each block in each ECU and various input signals. The microcomputer that calculates and outputs the amount, the input buffer that converts the digital input signal to a signal level that can be input to the microcomputer, the AD converter that converts the analog signal to a digital value that can be input to the microcomputer, and the power supply from the power supply. Also, an EEPROM (Electronically Erasable and Programmable Read Only Memory) that stores data, a communication driver that converts the output data of the microcomputer into a communication signal suitable for the communication standard, and a signal sent by another ECU to the microcomputer Consists of a communication receiver that converts to a level that can be input

The monitor 314 is composed of an operation receiving section 314b composed of button switches 314b1, 314b2, 314b3, 314b4, 314b5, and 314b6 for receiving monitor operations, and a display section 314a.

The display unit 314a is a liquid crystal display, but it may be an organic display and is not limited to this. It is composed of a part 314a3.

A first display section 314a1 positioned above the display section 314a displays information to be notified to the operator regarding display of warning icons and images displayed on the second display section 314a2.

A second display portion 314a2 located in the center of the display portion 314a and occupying most of the display portion displays state information of the excavator 100, captured images around the excavator 100, information for setting functions of the excavator 100, and the like. display.

A third display portion 314a3 positioned below the display portion 314a and above the operation reception portion 314b is positioned corresponding to the button switches 314b1, 314b2, 314b3, 314b4, 314b5, and 314b6 that constitute the operation reception portion 314b. , a mark representing the function corresponding to the operation button is displayed. The operator presses the button switches 314b1, 314b2, 314b3, 314b4, 314b5, and 314b6 corresponding to the marks displayed on the third display section 314a3 to operate the monitor 314 and set the functions of the hydraulic excavator 100. .

Next, a password input method will be described with reference to FIGS. 3 to 6. FIG.

When the engine key is inserted into the key cylinder and turned to the accessory position, power is turned on to the monitor 314, and the display section 314a shown in FIG. 3 transitions to the display section 314a shown in FIG.

The password input screen 630 displays a text 631 "Password" on the first display portion 314a1, and a text 632 "Please enter the password" displayed below the second display portion 314a2. The operator who turned the can be prompted to enter the password.

Furthermore, the password input screen 630 has password input portions 633a, 633b, 633c, and 633d each composed of four square figures for inputting a password composed of four-digit numbers, located in the center of the second display portion 314a2. is displayed, and numbers from 0 to 9 can be entered in the square figures on which the cursor 634 is placed above and below.

On the initial screen of the password input screen 630, the cursor 634 is positioned above and below the password input portion 633a, and the third display portion 314a3 displays the numbers of the password input portions 633a, 633b, 633c, and 633d where the cursor 634 is positioned. 635a means to decrease the number, 635b means to increase the number in the part where the cursor 634 is positioned, delete the number in the part where the cursor 634 is positioned, and move the cursor to the previous square figure position. 635c for moving and 635d for confirming the number of the portion where the cursor 634 is positioned are displayed.

If the button switch 314b3 or 314b4 is pressed while the cursor 634 is positioned above or below the password input area 633a, an arbitrary number is displayed in 633a. to display an arbitrary number and press the button switch 314b6, 636 is displayed like the password input section 633a in FIG. A similar operation is performed until the number of the password input section 633d is determined, and a password composed of four digit numbers is input to the password input sections 633a, 633b, 633c, and 633d.

When it is authenticated that the password entered here is the same as the password stored in engine ECU 511, home screen 610 is displayed on display portion 314a.

The home screen 610 is a display that serves as a starting point for operating the monitor 314, and displays a fuel gauge 611, a coolant temperature gauge 612, and a hydraulic oil temperature gauge 613 on the second display portion 314a2, and displays button switches on the third display portion 314a3. The text 614 "Menu" is displayed above 314b1.

After the home screen 610 is displayed on the monitor 314, the engine is started by turning the engine key inserted into the key cylinder from the accessory position to the start position.

If the four-digit numbers input to the password input sections 633a, 633b, 633c, and 633d do not match the password stored in the engine ECU 511, the display section 314a displays a message prompting re-input of the password. Even if you turn the engine key from the accessory position to the start position, the engine will not start.

Next, a password change method will be described with reference to FIGS. 6 to 10. FIG.

When the button switch 314b1 below the text 614 "Menu" on the third display portion 314a3 of the home screen 610 is pressed, the home screen 610 transitions to the menu screen 620 displayed on the display portion 314a of FIG.

The menu screen 620 is a screen for selecting items for setting functions of the hydraulic excavator 100 or checking detailed state information.

The items to be selected are displayed on the second display portion 314a2, and the respective items are arranged from top to bottom. The item for changing the password is the text 622 "change password", and the item for setting the PTO flow rate of the hydraulic excavator is the text 623 "set PTO flow rate".

An item is selected by moving the console 624 by operating the operation receiving unit 314b to highlight the selected item.

The functions assigned to the operation reception unit 314b are displayed on the third display unit 314a3.

For example, the text 625 "return" displayed above the button switch 314b1 represents the function of transitioning from the menu screen 620 to the home screen 610 by pressing the button switch 314b1.

Also, an icon 626 displayed above the button switch 314b3 and an icon 627 displayed above the button switch 314b4 represent functions of moving the console 624 up and down by pressing the button switches 314b3 and 314b4.

Furthermore, a text icon 628 labeled "determine" displayed above the button switch 314b5 represents a function of causing the menu screen 620 to transition to the password change screen 640 when the button switch 314b5 is pressed.

The password change screen 640 displays the text 641 "Change Password" in the first display portion 314a1, and the text 642 "Please enter the password to be changed" displayed below the second display portion 314a2. , the operator can naturally recognize how to change the password.

Further, the password change screen 640 includes change password input areas 643a, 643b, 643c, four square figures for inputting a change password composed of four-digit numbers, and four square figures at the center of the second display area 314a2. Numbers 0 to 9 can be entered in a square figure displaying 643d and having cursors 644 positioned above and below.

On the initial screen of the password change screen 640, the cursor 644 is positioned above and below the change password input section 643a, and the password input sections 643a, 643b, 643c, and 643d of the portions where the cursor 644 is positioned are displayed on the third display section 314a3. 645a means to decrease the number, 645b means to increase the number in the portion where the cursor 644 is positioned, deletes the number in the portion where the cursor 644 is positioned, and moves the cursor to the previous square figure position. 645c for moving to , and 645d for confirming the number at which the cursor 644 is positioned are displayed.

If the button switch 314b3 or 314b4 is pressed while the cursor 644 is positioned above or below the password input area 643a, an arbitrary number is displayed in 643a. If you press the button switch 314b6 to display an arbitrary number, 646 is displayed like the password input section 643a in FIG. A similar operation is performed until the number of the password input section 643d is determined, and a password composed of four digit numbers is input to the password input sections 633a, 633b, 633c, and 633d.

The password entered here changes not only the password stored in the engine ECU 511 but also the password stored in the integrated ECU 513 , and at the same time, the password change screen 640 changes to the password change completion notification screen 650 .

The reason why the changed password is stored in the integrated ECU 513 other than the engine ECU 511 is that the operator of the hydraulic excavator 100 can directly or indirectly obtain the changed password. In addition to storing the password to periodically transmit the password to the outside for storage and management, the password can be sent from the integrated ECU 513 to the display terminal 540 by wired connection or wireless connection. Furthermore, apart from the password stored in engine ECU 511, the password stored in engine ECU 511 can be displayed on monitor 314 only by a specific administrator by means of identifying an individual.

The password can be changed if the password change screen 640 is displayed in the password display section 314a, but it is also possible to add to the password change condition that the cut-off lever 312e is pulled upward. . By adding such a condition, even if the operator unintentionally touches the side levers 312c and 312d during password change, the hydraulic excavator 100 does not move, so the password can be safely input. Adding the fact that the cut-off lever 312e is pulled upward to the condition for changing the password means that the changed password will not be stored in the integrated ECU 513 if the control for storing the changed password in the integrated ECU 513 is on. Even in such a case, it is possible to incorporate it into the hydraulic excavator 100 .

The change completion notification screen 650 displays the text 651 "Password change" in the first display section 314a1, and displays the text 652 "Password change completed" in the center of the second display section 314a2. to let the operator know that the password change operation is complete.

A text 653 reading “return” is displayed above the button switch 314b1 of the third display section 314a3.

Next, the data communication network 520 will be described. The data communication network 520 is a mobile phone network such as 3G, LTE, 4G or 5G, but is not limited to this, and may be a wireless connection such as Wi-Fi. .

An external server 530 connected to the communication device 514 via the data communication network 520 is composed of a database server and a web server/API server.

Data including a password stored in integrated ECU 513 and transmitted from communication device 514 to external server 530 at a predetermined cycle is stored in a database server. The password currently stored in the engine ECU 511 can be checked using the terminal 540 by logging into the /API server.

Next, the portable terminal 540 will be described with reference to FIGS. 11 and 12. FIG.

The mobile terminal 540 is a smart phone, and includes a camera 710 , a home button 720 integrated with a fingerprint scanner, and a display section 730 . The mobile terminal 540 is not limited to a smartphone, but may be a tablet having a communication function, a PC, or a tablet connected to the data communication network 520 via a Wi-Fi router.

When the client presses the home button 720 , the unlock screen 810 is displayed on the display unit 730 .

On the unlock screen 810, a text 811 "Enter Password" is displayed above the display portion 730, and a password input portion 812 is displayed below it. 812 A key display portion 813 for selecting numbers to be entered is displayed.

By entering the password stored in the mobile terminal 540 in the password input section 812, the mobile terminal 540 is unlocked and the application 900 for logging in to the external server 530 installed in the mobile terminal 540 is activated. This enables the administrator of the hydraulic excavator 100 to manage the password for safely starting the engine starter by a simple method without hindering convenience.

The method of unlocking mobile terminal 540 is not limited to the method of entering a password. be released.

Mobile terminal 540 may be unlocked based on facial information captured by camera 710, or may be unlocked using biometric authentication such as blood vessel, retina, and voice.

13 to 15, a password confirmation method using application 900 for logging into external server 530 will be described.

When application 900 is activated, display unit 730 displays login screen 910 .

The login screen 910 includes a user ID input section 911, a login password input section 912, a login password storage display 913 for storing the input login password, a login display section 914 for logging into the external server 530, and an external It consists of a logout display section 915 for logging out from the server 530 and a key display section 915 for selecting alphanumeric characters to be entered in the user ID input section 911 and login password input section 912 .

When the client inputs the user ID and login password registered in the external server 530 in the user ID input field 911 and the login password input field 912 and taps the login display field 914, the portable terminal 540 and the external server 530 are connected, and the client transitions to a selection screen 920 for selecting information about the hydraulic excavator 100 to be displayed on the display unit 730 of the mobile terminal 540 .

Here, after the password is entered, if the login password storage display 913 is tapped before the login display portion 914 is tapped, the mobile terminal 540 is unlocked and the application 900 is started. A login screen 910 with a user ID and a login password entered in a portion 912 is displayed on the display portion.

By storing the login password in the mobile terminal 540 in this way, the client can access the external server 530 using not only the password of the mobile terminal 540 but also biometric authentication, which is more reliable and more convenient. , and the administrator of the hydraulic excavator 100 can manage the password for safely starting the engine starter by a simpler method without hindering convenience.

The selection screen 920 transitions to an information selection display 922 for selecting necessary hydraulic excavator information displayed below a text display 921 labeled "Menu" displayed above the display unit 730, and a login screen 910. and an input display 927 for transitioning to an information display screen 930 displaying information on the selected hydraulic excavator.

The information selection display 922 includes an error information selection display 923, an operation information selection display 924, a position information selection display 925, and a password selection display.

The client selects hydraulic excavator information by displaying a check display by tapping each display. For example, in FIG. 14, only the password selection display is selected, and the selection screen 920 transitions to the information display screen 930 by tapping the input display 927 .

The information display screen 930 is composed of an information display section 932 that displays the password change history displayed below the user ID 931 displayed above the display section 730, and a return display 934 for transitioning to the selection screen 920. It is

The information display unit 920 highlights the current password with a cursor 930 to display the password currently set in the hydraulic excavator 100 so that the client can easily recognize it.

Modifications of the embodiment are listed below. Modifications described below can be applied in combination as appropriate.

The anti-theft system 500 can be composed of an in-vehicle network 510 and a mobile terminal 540 . For example, the password stored in integrated ECU 513 may be displayed on mobile terminal 540 by wirelessly communicating between mobile terminal 540 and integrated ECU 513 . As wireless communication, Bluetooth communication can be used, but it is not limited to this. When the portable terminal 540 and the integrated ECU 513 are paired by Bluetooth communication, the password registered in the memory of the integrated ECU 513 is input into the portable terminal 540 so that the administrator of the hydraulic excavator 100 can easily and safely enter the password into the portable terminal 540 . can be displayed.

Alternatively, the anti-theft system 500 may be composed only of the in-vehicle network 510 . For example, the monitor 314 may be provided with a biometric authentication device such as a fingerprint scanner. By doing so, the password stored in the integrated ECU 513 can be easily and safely displayed on the display section 314 a of the monitor 314 . Furthermore, identification means for identifying an individual is not limited to authentication based on biometric information, and authentication may be performed using an operation pattern such as a combination of operation of the operation reception unit 314b and operation of an engine key, for example.

In the above description, a hydraulic excavator is used as an example of a construction machine, but the construction machine is not limited to a hydraulic excavator, and may be a wheel loader, a compact track loader, or other construction machine.

Although the embodiment of the present invention has been described above, the scope of the present invention is not limited to this, and can be expanded or modified without departing from the gist of the invention.

INDUSTRIAL APPLICABILITY The present invention relates to an anti-theft system for construction machinery and has industrial applicability.

500 construction machine theft system 510 in-vehicle network 511 engine ECU 512 monitor ECU 513 integrated ECU 514 communication device 520 data communication network 530 external server 540 portable terminal

Claims (7)

a control unit that enables the engine of the construction machine to operate on condition that the password stored in the storage unit is entered; a changing unit that changes the password stored in the storage unit; An anti-theft system for construction machinery, comprising: a management unit that automatically stores a changed password; and a display terminal that displays the changed password stored in the management device by authenticating with a specific means for identifying an individual. The anti-theft system for a construction machine includes a communication section that transmits the changed password to the management section installed outside the construction machine, and the construction machine comprises the storage section, the control section, and the changing means. , and said communication unit. 3. The anti-theft system for construction machinery according to claim 2, wherein said identifying means comprises first identifying means for causing said management unit to authenticate, and second identifying means for causing said display terminal to authenticate. 4. The anti-theft system for construction machinery according to claim 3, wherein said first identifying means is another password, and said display terminal can store said other password. The construction machine anti-theft system, wherein the second identifying means is at least biometric authentication. The construction machine has a cut-off lever for enabling or disabling an operation device for operating the construction machine, and the change means is the cut-off lever, and when the operation device is disabled, the password is changed. 6. The anti-theft system for construction machinery according to any one of claims 1 to 5, wherein A construction machine comprising: a control unit that enables operation of an engine on condition that a password stored in a storage unit is entered; and change means that changes the password stored in the storage unit, wherein The construction machine has a cut-off lever that enables or disables an operating device that operates the construction machine, and the changing means changes the password when the operating device is disabled by the cut-off lever. A construction machine characterized by permitting

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