JPH1178788A - Anti-theft device for hydraulic machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anti-theft device for a hydraulic machine to operate a hydraulic machine even when an operator forgets an ID number or a different operator not knowing an ID number is about to operate. SOLUTION: A hydraulic shovel comprises an engine starting circuit 30, a main hydraulic pump 7, a main hydraulic circuit 101 containing an actuator, such as a boom cylinder 8 and a control valve 6, and a pilot hydraulic circuit 102 containing a pilot pump 1. An anti-theft device for a hydraulic machine comprises a lock means, such as a solenoid valve 23, to control operation of the hydraulic shovel, a code input means, such as a key input device 21, an unlocking electronic circuit 22 to generate an unlocking signal to the solenoid valve 23 when predetermined code is inputted from the key input device 21, and a second input means, such as a handy terminal 24, to generate an unlocking signal to the unlocking electronic circuit 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an anti-theft device for a hydraulic machine, and more particularly to an anti-theft device for a hydraulic machine including a construction machine such as a hydraulic shovel.

[0002]

2. Description of the Related Art As a conventional anti-theft device for a hydraulic machine, there is, for example, an invention described in Japanese Patent Application Laid-Open No. 9-50584. A conventional anti-theft device for a hydraulic machine will be described with reference to FIGS. FIG. 8 is a diagram showing an appearance of a hydraulic excavator which is a hydraulic machine. As shown in FIG. 8, the excavator includes a lower traveling unit 200, an upper revolving unit 201, and a work implement, that is, a front 202. The front 202 includes a boom 203, an arm 204, and a bucket 205 that are vertically movably connected. It is composed of The lower traveling body 200 has left and right crawlers 206 (only one is shown) driven by a traveling motor 153,
A swing motor (not shown) is built in the upper swing body 201, and swings the upper swing body 201 with respect to the lower traveling body 200. Further, the boom 203, the arm 204, and the bucket 205 are driven vertically by the boom cylinder 8, the arm cylinder 150, and the bucket cylinder 151, respectively.

FIG. 9 is a diagram showing a hydraulic circuit of the above-mentioned hydraulic excavator, including an anti-theft device. As shown in the figure, this hydraulic circuit is formed of a main hydraulic circuit 101 and a pilot hydraulic circuit 102. The main hydraulic circuit 101
A main hydraulic pump 7 driven by an engine (not shown);
An actuator driven by pressure oil discharged from the main hydraulic pump 7, for example, a boom cylinder 8, and a main control valve 6 for controlling the direction and flow rate of the pressure oil supplied from the main hydraulic pump 7 to the boom cylinder 8 The main oil pressure supply line 7a of the main hydraulic pump 7 is provided with a main relief valve 9 for regulating the maximum pressure of the main hydraulic pump 7.
The pilot hydraulic circuit 102 is driven by an engine (not shown) to generate a primary pilot pressure. The pilot hydraulic circuit 102 is connected to a discharge line of the pilot hydraulic pump 1, and a pilot relief valve that keeps the primary pilot pressure constant. 2 and a valve operation circuit 30 that drives the main control valve 6 of the main hydraulic circuit 101 using the pilot primary pressure generated by the pilot hydraulic pump 1.

The valve operating circuit 30 is connected to the pilot primary pressure lines 3, 3a for transmitting the pilot primary pressure discharged from the pilot hydraulic pump 1, and the pilot primary pressure line 3a, and converts the pilot primary pressure into a pilot secondary pressure. It comprises a pilot valve device 4, and pilot secondary pressure lines 5 a, 5 c; 5 b, 5 d connected to the pilot valve device 4 and transmitting pilot secondary pressure to the main control valve 6.

The pilot valve device 4 includes a pair of pressure reducing valves 4a,
4b and a manual lever 4c for operating the pair of pressure reducing valves 4a and 4b, and the main control valve 6 is a hydraulic drive unit 6 connected to pilot secondary pressure lines 5a and 5c; 5b and 5d.
a, 6b and a spool 6c driven by the hydraulic drive units 6a, 6b to switch the oil passage between the main hydraulic pump 7 and the boom cylinder 8.

The anti-theft device 20 has code input means having a plurality of keys including a numeric keypad 21a from 0 to 9, for example, a key input device 21, and a numeric keypad 21a of the key input device 21 is pressed in the order of the password. When a predetermined code corresponding to a password is input, the electronic control unit includes an unlocking electronic circuit 22 for transmitting an ON electric signal as an unlocking signal, and a solenoid valve 23 as locking means. The solenoid valve 23 is an open / close valve having a solenoid driving unit 23a electrically connected to the unlocking electronic circuit 22 and a spool 23b driven by the solenoid driving unit 23a.
The pilot primary pressure line 3 is connected between the pilot hydraulic pump 1 and the pilot valve device 4.

In the conventional anti-theft device for a hydraulic machine configured as described above, when the numeric keypad 21a of the key input device 21 is pressed in the order of the password, the unlocking electronic circuit 22 sends the signal to the solenoid driving unit 23a. Thus, an electric signal for unlocking is given, and it is switched from the illustrated closed position to the open position. Then, the pilot primary pressure discharged from the pilot hydraulic pump 1 is maintained at a constant pressure by the pilot relief valve 2, and is guided to the pressure reducing valves 4a, 4b via the pilot primary pipes 3, 3a. In this situation, for example, when the operator operates the manual lever 4c in the direction A in the figure, the pressure reducing valve 4a is operated, and the hydraulic drive unit 6a is controlled by the pilot drive according to the operation amount of the manual lever 4c via the pilot secondary pressure piping 5a, 5c. The secondary pressure is led and the spool 6 of the main control valve 6
c moves in the C direction in the figure. Due to the movement of the spool 6C, the pressure oil discharged from the main hydraulic pump 7 is guided to the rod side of the boom cylinder 8, the cylinder rod is retracted, and the boom 203 attached to the cylinder rod operates. When the manual lever 4c is operated in the direction B, the pressure reducing valve 4b is operated, and a pilot secondary pressure according to the operation amount of the manual lever 4c is guided to the hydraulic drive unit 6b via the pilot secondary pressure pipes 5b and 5d. , Spool 6 of main control valve 6
c moves in the direction D in the drawing, and the pressure oil discharged from the main hydraulic pump 7 is guided to the bottom side of the boom cylinder 8 to extend the cylinder rod, and the boom 203 attached to the cylinder rod moves in the opposite direction to the above. The excavator is operated by being moved.

On the other hand, when no electric signal for unlocking is transmitted from the unlocking electronic circuit 22, the spool 23b
Is maintained at the illustrated closed position by the force of the spring 23c. Then
The pilot primary pressure discharged from the pilot hydraulic pump 1 is cut off, and the pilot secondary pressure is not generated even when the manual lever 4c of the pilot valve device 4 is operated. Therefore, the main control valve 6 and the boom cylinder 8 are operated. You will not be able to do it.

[0009]

However, in the above-mentioned prior art, if the operator forgets the password, or if another operator who does not know the password attempts to operate, the hydraulic machine cannot be operated. There is a problem.

The present invention has been made in view of such problems of the prior art, and has as its object to prevent theft as much as possible, and to allow the operator to forget the password, It is an object of the present invention to provide a hydraulic machine anti-theft device that can operate a hydraulic machine even when another operator who does not know the operation attempts to operate the hydraulic machine.

[0011]

According to a first aspect of the present invention, there is provided an anti-theft apparatus for a hydraulic machine, comprising: an engine; an engine starting system circuit for starting the engine; A main hydraulic circuit including a main hydraulic pump to be driven, an actuator driven by hydraulic oil discharged from the main hydraulic pump, and a main control valve for controlling a flow rate of hydraulic oil supplied from the main hydraulic pump to the actuator. And a pilot hydraulic circuit including a pilot hydraulic pump, and a pilot hydraulic circuit that controls the main hydraulic circuit using a pilot pressure generated by the pilot hydraulic pump, and controls the operation of the hydraulic machine. Means, code input means, and, when a predetermined code is input to the code input means, generates an unlock signal to the lock means. In anti-theft device for a hydraulic machine comprising a unlocking electronic circuit that is characterized by having a second input means for generating an unlock signal to the unlocking electronic circuit.

According to the above construction, the locking means provided in the hydraulic system shuts off the hydraulic oil flowing through the hydraulic pipeline and disables the operation of the hydraulic machine, thereby preventing theft. By issuing a signal instructing the unlocking electronic circuit to unlock the hydraulic circuit, the hydraulic pipeline blocked by the locking means can be communicated.

Therefore, even if the password is forgotten or another operator who does not know the password attempts to operate, the hydraulic machine can be operated.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment of the present invention.
This will be described with reference to FIG. FIG. 1 is a hydraulic circuit diagram provided with a theft prevention device according to a first embodiment of the present invention, FIG. 2 is a block diagram showing details of an unlocking electronic circuit in FIG. 1, and FIG. 3 is a flowchart showing an unlocking operation. is there. The same parts as those in FIG. 9 used in the description of the related art described above are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 1, the anti-theft device of a hydraulic machine such as a hydraulic shovel according to the present embodiment comprises an unlocking electronic circuit 2.
2, a communication device 25 for transmitting a signal output from a handy terminal 24 as an external input device to the unlocking electronic circuit 22 is attached. The communication device 25 is provided with a service switch 26 for switching between conduction and disconnection between the unlocking electronic circuit 22 and the handy terminal 24. When the service switch 26 is turned on, the handy terminal 24 and the unlocking electronic circuit 22 become conductive. It is supposed to. The handy terminal 24 is provided with an operation switch (not shown), and an unlock instruction signal can be output by operating the switch (not shown). That is, the unlock instruction signal from the handy terminal 24 can be transmitted to the unlocking electronic circuit 22 only after the switch (not shown) of the handy terminal 24 and the service switch 26 are turned on.

As shown in FIG. 2, the unlocking electronic circuit 22 stores an input section 22a for receiving signals from the key input device 21 and other external input devices, and an electric signal pattern for instructing unlocking. Storage unit 22b to perform
a comparison / arithmetic unit 22c that compares the electric signal input to a with the electric signal pattern stored in the storage unit 22b and indicates an electric signal to be output to the outside based on the result of the comparison;
An output unit 22d for transmitting a signal based on an instruction from the comparison / calculation unit 22c to a solenoid driving unit 23a of the solenoid valve 23 shown in FIG. Also, the comparison / arithmetic unit 2
2c, the service switch 26 is turned on and the input unit 22
It is possible to measure the time when “a” is enabled to receive a signal from an external input device other than the key input device 21.

Next, the operation will be described with reference to FIG. First, it is checked in step S1 whether the service switch 26 is ON. If the service switch 26 is ON, the process proceeds to the next step S2.

In step S2, it is determined whether or not a signal transmitted from the handy terminal 24 to the input section 22a of the unlocking electronic circuit 22 is an instruction for unlocking. At this time, the comparison / calculation unit 22c compares the signal input to the input unit 22a with the signal pattern stored in the storage unit 22b to determine whether they match, and if they match, the procedure proceeds to step S3. Proceed to.

In step S3, an unlocking process is performed by outputting an electric signal from the output unit 22d to the solenoid driving unit 23a. Note that this unlocking process is the same as the unlocking process described in the section of the related art, and a description thereof will be omitted.

In the present embodiment, the case where "a signal for instructing unlocking is not transmitted to the unlocking electronic circuit 22 even if, for example, 10 seconds or more have passed since the service switch 26 was turned on" is set in this processing. It is set as a condition to exit the loop.

In step S2, the handy terminal 2
If it is determined that the signal transmitted from Step 4 to the unlocking electronic circuit 22 is not a signal instructing unlocking, the process proceeds to Step S4, and it is determined whether the time measured by the comparison / calculation unit 22c is within 10 seconds. I do. If the measurement time is within 10 seconds, the process returns to step S2, and it is determined again whether a signal instructing unlocking is transmitted from the handy terminal 24 to the unlocking electronic circuit 22. Therefore, if the data received by the unlocking electronic circuit 22 does not indicate the unlocking, the procedure S2 →
The process of step S4 → step S2 is repeated, and after 10 seconds have elapsed from when the service switch 26 was turned on, when the process reached step S4, that is, the service switch 26
If the signal for instructing unlocking is not transmitted for 10 seconds after is turned on, the process is terminated.

Also, in step S1, if the service switch 26 is off, this process is terminated.

Therefore, according to the present embodiment, by switching the solenoid valve 23 provided in the pilot hydraulic circuit, the pilot hydraulic circuit can be controlled and theft can be prevented. Since a signal for instructing unlocking can also be transmitted from the handy terminal 24, which is an input device, even if the security code is forgotten or another operator who does not know the security code attempts to operate, the hydraulic pressure is not changed. Excavator can be operated.

In the present embodiment, the hydraulic circuit having the boom cylinder 8 is described as an actuator.
50, the bucket cylinder 151, the travel motor 153, the turning motor, and the like also have the same valve operation circuit 30, so that they can have the same configuration.

In this embodiment, the input wait time of the unlock instruction signal is set to 10 seconds, but this value may be arbitrarily changed.

Further, in this embodiment, the start measurement time of the unlocking process is set when the service switch 26 is turned on.
May be set as the start measurement time of the service mode processing.

In the present embodiment, the handy terminal 24 is provided as an external input means, but a portable personal computer or the like may be used.

A second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a view showing an anti-theft device according to a second embodiment of the present invention. It should be noted that the above-described prior art and the first
The same reference numerals are given to the same parts as those described in the embodiments, and the description thereof will be omitted.

Reference numeral 41 denotes key input means. The key input means 41 includes numeric keys 41a from 0 to 9 and a display portion 41b for displaying the input value when the numeric key 41a is input. I have. The key input means 41 is connected to the unlocking electronic circuit 22, and the signal output from the key inputting means 41 is taken into the unlocking electronic circuit 22 and the signal output from the unlocking electronic circuit 22 is input to the unlocking electronic circuit 22. A part is taken into the key input means 41. Other configurations are the same as those of the first embodiment.

Next, the operation will be described. When a switch (not shown) of the handy terminal 24 is turned on, a signal for displaying a password is transmitted from the handy terminal 24. When the service switch 26 is turned on to make the unlocking electronic circuit 22 and the handy terminal 24 conductive, a signal transmitted from the handy terminal 24 is taken into the unlocking electronic circuit 22. When it is determined that the signal input in the comparison / calculation unit 22c of the unlocking electronic circuit 22 is a signal instructing the display of the personal identification number, the output unit 22d causes the key input device 41 to display the personal identification number on the display unit 41b. Is output, and the password is displayed on the display section 41b.

Therefore, according to the present embodiment, the operator can output a signal for instructing the unlocking electronic circuit 22 to unlock by pressing the numeric keypad 41a in the order of the password displayed on the display section 41b. Therefore, the same effect as in the first embodiment can be obtained.

In this embodiment, the display 41 is connected to the unlocking electronic circuit 22 from the handy terminal 24.
A command signal instructing b to display the personal identification number is transmitted, and this command signal forms one of the signals for causing the unlocking electronic circuit 22 to generate the unlocking signal.

A third embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a hydraulic circuit diagram provided with the anti-theft device according to the third embodiment of the present invention, and FIG. 6 is a flowchart showing the unlocking operation of the third embodiment. Note that the same reference numerals are given to the same portions as those described in the above-described related art and the first embodiment, and description thereof will be omitted.

In FIG. 5, reference numeral 27 denotes a key switch for communicating with the unlocking electronic circuit 22; 27a denotes its key hole; 28 denotes a key inserted into a key hole 27a of the key SW 27;
This is a judgment circuit for judging whether or not N has been reached. Key S
When W27 is turned on, the determination circuit 28 determines whether the key SW2
7 is transmitted to the unlocking electronic circuit 22 to instruct the unlocking electronic circuit 22 to unlock. In addition, the first determination circuit 28
A service switch 26 similar to that of the embodiment is provided. When the service switch 26 is turned on, the key S
The signal output from W27 communicates with the unlocking electronic circuit 22.

Next, the operation will be described with reference to FIG. First, in step S11, it is confirmed whether the service switch 26 is ON. If the service switch 26 is ON, the process enters a service mode in which an external input signal other than the key input device 21 is validated, and proceeds to step S12.

In step S12, it is determined whether or not the key SW 27 is ON. If the key SW 27 is ON, the process proceeds to step S13, where the unlocking electronic circuit 22 performs an unlocking process. The determination process in step S12 and the unlocking process in step S13 are the same as those in the first embodiment, and a description thereof will not be repeated.

In this embodiment, as in the first embodiment, a signal for instructing the unlocking electronic circuit 22 to unlock is transmitted to the unlocking electronic circuit 22 even if, for example, 10 seconds or more have passed since the service switch 26 was turned on. "No" is set as a condition for exiting this service mode.

If it is determined in step S12 that the ON signal has not been transmitted from the key SW 27 to the unlocking electronic circuit 22, the flow advances to step S14 to determine whether the time measured by the comparison / calculation unit 22c is within 10 seconds. If the measurement time is within 10 seconds, the procedure returns to step S12, and it is determined again whether a signal instructing the unlocking electronic circuit 22 to unlock is transmitted from the key SW 27. Therefore, as long as the unlocking electronic circuit 22 does not receive the ON signal from the key SW 27, the procedure S12 is performed.
→ Step S14 → Step S12 is repeated, and after 10 seconds have elapsed from the time when the service switch 26 is turned ON, when the procedure S14 is reached, that is, the service switch 2
If no unlock instruction signal is transmitted for 10 seconds after the switch 6 is turned on, the service mode process is terminated.

In step S11, if the service switch 26 is turned off, the service mode process is terminated.

Therefore, according to this embodiment, the pilot hydraulic circuit can be controlled by switching the solenoid valve 23 provided in the pilot hydraulic circuit to prevent theft, while the key input device 21 can be controlled in the service mode. A signal for instructing unlocking can also be transmitted with the key SW which is an input device other than the above, so even if you forget the password or if another operator who does not know the password tries to operate it, Can operate hydraulic machines.

Further, if the key SW 27 of the present embodiment is arranged in a place where it is difficult to understand, a normal ignition key can be used instead of creating a special key.

A fourth embodiment of the present invention will be described with reference to FIG. FIG. 7 is a circuit diagram including the anti-theft device according to the fourth embodiment of the present invention. Note that the same reference numerals are given to the same portions as those described in the above-described related art and the first embodiment, and description thereof will be omitted.

In FIG. 7, 31 is a battery, 32 is a starter circuit, 33 is a battery relay, and 34 is locking means, for example, a relay interposed between lead wires connecting the starter circuit 32 and the battery relay 33. , Starter circuit 32, battery relay 33,
The relay 34 forms an engine start system circuit 30.

The unlocking operation of the present embodiment configured as described above is performed according to the above-described flowchart shown in FIG. 3, as in the first embodiment. Since the processes in steps S1, S2, and S4 are the same as those in the first embodiment, only the unlocking process in step S3 will be described here. When a signal for instructing unlocking is output from the handy terminal 24 to the unlocking electronic circuit 22, a signal for driving the relay 34 is output from the unlocking electronic circuit 22. Then relay 3
4, the engine starting system circuit is closed, the starter circuit 32 operates to start the prime mover (not shown), and the prime mover is driven by supplying fuel to the prime mover via a throttle lever or the like (not shown). .

Therefore, according to the present embodiment, the switching operation of the relay 34, which is a locking means provided on the circuit, can control the starting system of the engine and prevent theft. Since a signal for instructing unlocking can also be transmitted from the handy terminal 24 which is an input device other than the input device 21, if the security code is forgotten or another operator who does not know the security code attempts to operate. In this case, the hydraulic machine can be operated.

[0046]

According to the anti-theft device for a hydraulic machine of the present invention, the lock oil provided in the pilot hydraulic system shuts off the hydraulic oil flowing through the hydraulic pipeline, or the engine is started by the lock provided in the engine start system circuit. To prevent the theft by controlling the operation of the hydraulic machine, and to provide a second input means capable of transmitting a signal to the unlocking electronic circuit. By issuing a signal for instructing unlocking, the hydraulic line blocked by the locking means can be connected or the engine can be started, so if you forget your security code or if you do not know the security code, Can operate the hydraulic machine even if the operator attempts to operate the hydraulic machine.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram including a first embodiment of the present invention.

FIG. 2 is a flowchart showing an unlocking operation in the first embodiment shown in FIG.

FIG. 3 is a block diagram showing details of an unlocking electronic circuit provided in the first embodiment shown in FIG. 1;

FIG. 4 is a circuit diagram showing a second embodiment of the present invention.

FIG. 5 is a hydraulic circuit diagram including a third embodiment of the present invention.

FIG. 6 is a flowchart showing an unlocking operation in the third embodiment shown in FIG.

FIG. 7 is a circuit diagram showing a fourth embodiment of the present invention.

FIG. 8 is a side view showing the appearance of a general hydraulic excavator.

FIG. 9 is a hydraulic circuit diagram provided with a conventional anti-theft device provided in the hydraulic excavator shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pilot hydraulic pump 6 Main control valve 7 Main hydraulic pump 8 Boom cylinder (actuator) 21 Key input device (Code input device) 22 Unlocking electronic circuit 23 Solenoid valve (Lock means) 24 Handy terminal (Input means) 27 Key SW ( Input means) 31 Battery 32 Starter circuit 34 Relay (Lock means) 41 Key input device (Code input device)

Claims (4)

[Claims] 1. An engine, an engine starting system circuit for starting the engine, a main hydraulic pump driven by the engine, an actuator driven by pressure oil discharged from the main hydraulic pump, and A main hydraulic circuit including a main control valve that controls a flow rate of the hydraulic oil supplied to the actuator; and a pilot hydraulic pump. The main hydraulic circuit is controlled using a pilot pressure generated by the pilot hydraulic pump. A lock unit provided in a hydraulic machine having a pilot hydraulic circuit and controlling the operation of the hydraulic machine, a code input unit, and a lock unit when a predetermined code is input to the code input unit. An anti-theft device for a hydraulic machine having an unlocking electronic circuit for generating an unlocking signal, wherein the unlocking electronic circuit generates an unlocking signal. An anti-theft device for a hydraulic machine, comprising a second input means for causing the anti-theft device to operate. 2. The anti-theft device for a hydraulic machine according to claim 1, wherein said lock means is provided in at least one of said pilot hydraulic circuit and said engine starting system circuit. 3. The anti-theft device for a hydraulic machine according to claim 1, wherein the second input means is a handy terminal. 4. The anti-theft device for a hydraulic machine according to claim 1, wherein said second input means is a key switch.