JP4685295B2 - Work vehicle anti-theft device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a work vehicle antitheft device.
[0002]
[Prior art]
Work vehicles such as hydraulic excavators and bulldozers are often left at work sites that are not well managed by the user at night and on holidays, and as a result, there is a high risk of theft. A technique for preventing this theft is disclosed in, for example, Japanese Patent Laid-Open No. 9-48324.
That is, as shown in FIG. 4, the anti-theft device 50 is provided in the engine starting system 63 that connects the starter 61 and the battery 62. The anti-theft device 50 turns on a starter control relay 53 provided in series with the engine starting system 63 when the control unit 52 determines that the password entered with the numeric keypad 51 is “true”. It is configured. For this reason, even if a third party operates the key switch 64, the starter control relay 53 is OFF, power is not supplied to the starter 61, the engine 60 cannot be started, and theft is prevented.
[0003]
Further, in this publication, as shown in FIG. 5, an example in which a solenoid valve 54 is used as a device other than the control relay 53 that operates in response to “true” and “false” of the password entered by the numeric keypad 51. Cite. That is, the solenoid valve 54 is provided in the pilot hydraulic pipe 73 between the pilot hydraulic pump 71 and the pilot valve device 72 so that the transmission of the pilot pressure to the pilot valve device 72 can be cut off. As a result, even if a third party starts the engine 60 and operates the pilot valve device 72 by lever operation, the main control valve 74 cannot be operated by the pilot pressure, and the pressure from the main hydraulic pump 75 to the hydraulic cylinder 76 cannot be controlled. Since oil cannot be supplied, the vehicle cannot be driven and theft is prevented.
[0004]
[Problems to be solved by the invention]
However, in the above-described prior art, not only a PIN number input device such as the numeric keypad 51 is required, but also a device such as a relay 53 or a solenoid 54 that operates according to the PIN code “true” or “false” is newly installed. Therefore, the anti-theft device is expensive.
[0005]
The present invention has been made paying attention to the above-described problem, and an object of the present invention is to provide a work vehicle anti-theft device that is low in cost and excellent in the anti-theft effect.
[0006]
[Means, actions and effects for solving the problems]
In order to achieve the above object, the first invention confirms that the operator is a regular user in a work vehicle including an actuator that controls the amount of fuel injected into the engine according to a command from the control means. And the control means controls the actuator so that the fuel injection amount to the engine is equal to or less than a predetermined value until it is confirmed by the regular user confirmation means that the operator is a regular user. It is configured to control.
[0007]
That is, it is possible to prevent theft by making it difficult to start the engine until it is confirmed that the operator is an authorized user.
This engine control actuator is a standard equipment, and unlike the case where a new equipment is additionally provided, there is no part cost or modification cost, resulting in a low cost.
[0008]
Further, the second aspect of the invention provides an actuator for controlling the fuel injection amount to the engine in accordance with a command from the control means, and the tilt angle of the swash plate of the variable displacement hydraulic pump driven by the engine from the control means. In a work vehicle having a swash plate drive actuator that is controlled in accordance with a command, the work vehicle is provided with a regular user confirmation unit that confirms that the operator is a regular user, and the control unit is configured such that the regular user confirmation unit The actuator is controlled so that the amount of fuel injected into the engine is less than or equal to a predetermined value until the user is confirmed to be a user, and the tilt angle of the swash plate of the variable displacement hydraulic pump is greater than or equal to a predetermined value In this way, the swash plate drive actuator is controlled.
[0009]
That is, it is possible to prevent theft by making it difficult to start the engine until it is confirmed that the operator is an authorized user. Even when the engine is started, the discharge amount of the hydraulic pump is set to a predetermined amount or more, so that the load torque becomes excessive, the engine can be stalled, and unauthorized use or theft of the work vehicle can be surely prevented. .
The engine control actuator and the pump control actuator are standard equipment, and unlike the addition of a new equipment, there is no part cost or modification cost, resulting in low costs.
[0010]
Furthermore, in a third aspect of the invention, the authorized user confirmation unit includes a switch that is also used as a switch used for an operation or setting other than the anti-theft function when the authorized user is confirmed.
[0011]
Since the authorized user confirmation means also uses the standard switches as an input device for authorized user confirmation, a new input device is unnecessary, and a low-cost anti-theft device that can be dealt with only by correcting the program. Can do.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments will be described in detail with reference to the drawings.
As shown in FIG. 1, the discharge oil from a variable displacement hydraulic pump 2 driven by an engine 1 is supplied to a hydraulic actuator 4 such as a hydraulic cylinder or a hydraulic motor via an operation valve 3. Yes. The engine 1 is provided with a fuel injection pump 11 and a governor 12 in parallel. The fuel control lever 12a of the governor 12 is driven by a motor 13 that is driven and controlled by the controller 5, and the driving position of the fuel control lever 12a is detected by a position sensor 14 (for example, a potentiometer). The detection signal of the position sensor 14 is input to the controller 5 as a feedback signal when driving the motor 13.
The throttle dial 15 for setting the target rotational speed when the engine 1 is idling includes a potentiometer, and outputs a throttle signal corresponding to the target rotational speed to the controller 5.
An electromagnetic pickup type rotation sensor 16 is provided in parallel on the output shaft of the engine 1 and outputs a detection signal to the controller 5.
[0013]
The variable displacement hydraulic pump 2 includes a swash plate 2a whose tilt angle is driven by a swash plate drive actuator 17, and one rotation of the hydraulic pump 2 according to a change in the tilt angle of the swash plate 2a. The hit discharge flow rate is changed.
The swash plate drive actuator 17 takes in the load pressure PLS of the hydraulic actuator 4 and the pump discharge pressure Pp of the hydraulic pump 2, and includes a solenoid 17 a that is driven by a command from the controller 5. Based on the command, the tilt angle of the swash plate 2a is controlled in accordance with the load pressure PLS and the pump discharge pressure Pp, and the flow rate control or horsepower control of the hydraulic pump 2 is performed.
[0014]
The monitor panel 20 includes a liquid crystal display 21, a switch unit 22 including a plurality of switches, and a control unit 23, and exchanges various signals with the controller 5.
As shown in FIG. 2, the switch unit 22 includes vehicle operation switches such as a work mode selection switch, a travel speed changeover switch, a lighting switch, and a wiper switch, and switches for selecting display items on the liquid crystal display 21. It is installed. Some of these switches are switched to the function of the numeric keypad 22a according to the display contents, and are used for selection of display items and numerical value input.
The control unit 23 controls display contents including screen switching on the liquid crystal display 21 according to operation signals of the switches of the switch unit 22 and signals from the controller 5, and control signals such as work mode and travel mode. Is output to the controller 5.
[0015]
On the liquid crystal display 21, display items such as menu display, monitoring display, failure history display, initial value setting display, maintenance display, brightness / contrast adjustment display, and anti-theft display are allocated and displayed on a plurality of screens. The monitoring display for displaying the vehicle state includes a meter display relating to an engine coolant temperature gauge, a fuel remaining amount gauge, and the like, and an alarm display relating to engine oil pressure, engine oil amount, hydraulic oil amount, and the like. The maintenance display items include engine oil, engine oil filter, and the like that need periodic replacement / inspection replenishment, and display a maintenance history or display that prompts maintenance.
[0016]
By switching from the menu display to the anti-theft display, the anti-theft function can be set. By setting the anti-theft function to ON, every time the vehicle is turned on by the key switch from the next time, a display for requesting the input of a password is displayed. Until the correct password is input, an engine stop command is output to the controller 5, and the display on the liquid crystal display 21 is not switched from the password input request display to another screen, and the engine 1 cannot be started. .
[0017]
The control contents of the control unit 23 in the anti-theft function will be described with reference to FIG.
When the control unit 23 is turned on by the key switch operation, it is determined in step S1 whether or not the anti-theft function is set to ON. If “YES”, the process proceeds to step S2 and the liquid crystal display 21 is activated. A password input request screen is displayed on the screen and switch operations other than the numeric keypad 22a are invalidated. Next, in step S3, it is confirmed whether or not a password is entered by the numeric keypad 22a. If "YES", the process proceeds to step S4, and it is determined whether or not the entered password is correct. If “NO” in the step S3 or step S4, the process proceeds to a step S5 to output a “fuel cut command” and a “discharge flow rate MAX command” to the controller 5 and then return to the step S2. If “NO” in step S1 or “YES” in step S4, the process proceeds to step S6 to shift to normal control, and the liquid crystal display 21 is switched to menu display and each switch operation is validated.
[0018]
In response to the “fuel cut command”, the controller 5 drives the motor 13 so that the fuel control lever 12 a of the governor 12 moves to a lever position where the fuel injection amount becomes zero, and prohibits the start of the engine 1. The controller 5 receives the “discharge flow rate MAX command” and outputs a drive signal to the solenoid 17 a of the swash plate drive actuator 17 so that the tilt angle of the swash plate 2 a of the hydraulic pump 2 is maximized. Since the discharge side hydraulic circuit of the hydraulic pump 2 is closed when the vehicle is started, the hydraulic pressure increases when the hydraulic pump 2 is driven, and the pump absorption torque becomes a large value. Even if the engine 1 is started, the load torque Stall.
On the other hand, when the control unit 23 shifts to the normal control, the monitor panel 20 can be switched from the menu display to a desired display item, and each switch operation is also effective, so that the vehicle can be driven freely.
[0019]
According to the above-described embodiment, the anti-theft function is turned on so that the monitor panel 20 requests the password input every time the vehicle is started, and the fuel injection amount is set to zero until the correct password is input. Since the control for prohibiting the starting of 1 is performed, unauthorized driving of the vehicle by a third party can be prohibited, and theft can be prevented. Furthermore, until the correct password is input, control for maximizing the pump discharge amount is performed in addition to the fuel injection amount control. As a result, even if the engine starts, a large load torque acts on the engine 1 and the engine 1 is stalled, so that unauthorized driving of the vehicle by a third party can be surely prohibited. Obtainable.
In addition, the anti-theft device of the above embodiment does not need to install a new device for a standard specification vehicle, and can be handled only by changing the control program using the standard specification vehicle equipment. Is also a very good device.
[0020]
Note that the present invention is not limited to the above-described embodiment, and it goes without saying that changes and modifications can be made within the scope of the present invention.
For example, the anti-theft control performed by the control unit 23 of the monitor panel 20 may be controlled on the controller 5 side.
Further, the anti-theft effect can be obtained by omitting the anti-theft control for maximizing the pump discharge amount and using only the anti-theft control for reducing the fuel injection amount to zero.
A touch panel may be attached to the surface of the liquid crystal display, a numeric keypad may be displayed on the display screen, and a numerical value such as a password may be input.
If the monitor panel does not have a numeric keypad, use switches arranged in parallel on the monitor panel, and switch multiple switches after simultaneous operation of multiple switches (for example, keep pressing the vehicle speed selector switch and lighting switch simultaneously for 5 seconds). You may comprise so that it may confirm a legitimate user by the PIN code input operated in a predetermined order. The plurality of switches used for the regular user confirmation are not limited to those provided in parallel on the monitor panel, and for example, switches provided on a console near the driver's seat may be used.
As a means for confirming that the user is a legitimate user, it is possible to use a method such as an ID card, a hidden switch, and a fingerprint collation in addition to a password and a password.
Note that the fuel injection amount does not need to be completely reduced to zero. When the antitheft control for maximizing the pump discharge amount (tilt angle of the swash plate) is used in combination, for example, the fuel injection amount of about the low idle rotation Then, the engine can be surely stalled by the load torque of the pump. Further, at this time, it is not necessary to maximize the pump discharge amount, and the engine can be stalled if a load torque larger than the engine torque during low idling can be generated.
[0021]
As described above, according to the present invention, the engine is prohibited from starting unless it is confirmed that the user is a legitimate user, so that unauthorized driving of the vehicle by a third party is impossible, and theft is surely ensured. Can be prevented.
Further, the anti-theft device of the present invention can be handled only by changing the control program using a device mounted on a standard specification vehicle, so that it is not necessary to add a new device. Is obtained.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram according to an embodiment.
FIG. 2 is a plan view of a monitor panel.
FIG. 3 is a control flowchart according to the embodiment.
FIG. 4 is a system configuration diagram of a prior art.
FIG. 5 is a system configuration diagram of another aspect of the prior art.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Hydraulic pump, 2a ... Swash plate, 3 ... Operation valve, 4 ... Hydraulic actuator, 5 ... Controller, 11 ... Fuel injection pump, 12 ... Governor, 12a ... Fuel control lever, 13 ... Motor, 17 ... Swash plate drive actuator, 17a ... solenoid, 20 ... monitor panel, 21 ... liquid crystal display, 22 ... switch part, 22a ... numeric keypad, 23 ... control part.

Claims (2)

An actuator for controlling the fuel injection amount to the engine according to a command from the control means, and a swash plate for controlling the tilt angle of the swash plate of the variable displacement hydraulic pump driven by the engine according to the command from the control means In a work vehicle equipped with a drive actuator,
The controller includes a regular user confirmation unit that confirms that the operator is a regular user, and the control unit determines the amount of fuel injected into the engine until the regular user confirmation unit confirms that the operator is a regular user. The actuator is controlled so as to be below a predetermined value, and the swash plate is driven so that the tilt angle of the swash plate of the variable displacement hydraulic pump is maximized so that the engine is stalled by the load even when the engine is started. An anti-theft device for a work vehicle, characterized by controlling an actuator.   2. The antitheft device for a work vehicle according to claim 1, wherein the authorized user confirmation means includes a switch that is also used as a switch used for an operation or setting other than the antitheft function when the authorized user is confirmed. .

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