JP2003322112A - Abnormality detecting device of construction equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an abnormality detecting device of construction equipment that can detect an abnormality in a main hydraulic system. <P>SOLUTION: In a hydraulic shovel 1 including an engine 22, a hydraulic pump 23 driven by the engine 22, a hydraulic cylinder 15 for boom for driving a lower boom 9, an operation lever 27a for manually operating the cylinder 15, a control valve 25 for boom, a potentiometer 27b for detecting the amount of operation of the lever 27a, solenoid valves 31 and 32 for controlling pilot pressure to the valve 25, and a selector valve 37 to communicate with or block a pilot pipe path, there is provided an abnormality/operation information processing part 41 for determining an abnormality when the potentiometer 27b detects that the lever 27a is not operated, that a pilot pressure block control part 38 sets the valve 37 to a block position, and that the lower boom 9 is operated by an angle sensor 19 for boom. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine such as a hydraulic excavator, and more particularly to a construction machine abnormality detection device for detecting abnormality of the construction machine.

[0002]

2. Description of the Related Art For example, a hydraulic excavator, which is one of construction machines, has a lower traveling body, an upper revolving body provided on the lower traveling body so as to be revolvable, and a boom connected to the upper revolving body so as to be elevated and lowered. An articulated front device including a work tool such as an arm and a bucket is provided.

The undercarriage, the upper revolving structure, and the front device constitute a driven member of a hydraulic drive device provided in the hydraulic excavator. This hydraulic drive system
Generally, a prime mover such as an engine, a hydraulic pump driven by the prime mover, a boom hydraulic cylinder, an arm hydraulic cylinder, and a bucket hydraulic cylinder that respectively drive the boom, the arm, and the work implement by the pressure oil discharged from the hydraulic pump. Multiple hydraulic actuators, including hydraulic cylinders
It has a drive system main hydraulic system including a control valve for controlling the flow of the pressure oil discharged from the hydraulic pump to these hydraulic actuators, and an operating means for manually operating the hydraulic actuator.

The control valve drive system is usually a hydraulic pilot system. In this case, the hydraulic drive system includes a pilot circuit including, for example, a pilot pump driven by the prime mover, and a solenoid valve that controls pilot pressure to the control valve according to an operation amount (electrical signal) of the operation means. I have more.

In the hydraulic drive system thus constructed, for example, a small metal piece of a mechanical component of the hydraulic drive system may be peeled off in a hydraulic circuit including the main hydraulic system and the pilot circuit. Dust in the atmosphere may get mixed into this hydraulic circuit. At this time,
When foreign matter such as small pieces of metal or dust gets into the inside of the solenoid valve, for example, the drive part of the solenoid valve may be caught by the foreign matter and cause malfunction.

That is, when such malfunction occurs in, for example, the solenoid valve for controlling the control valve of the hydraulic cylinder for the boom, even if the operator operates the operating means so as to stop the boom, the solenoid valve moves to the control valve. The pilot pressure continues to be output. As a result, the boom hydraulic cylinder may continue to operate and the front device may collide with the ground against the intention of the operator.

In order to avoid such a situation, for example, as described in JP-A-7-19207,
A pressure sensor is provided between the solenoid valve and the control valve in the pilot circuit, and the pilot pressure signal detected by this pressure sensor is compared with the operation signal (electrical signal) output from the operating means. There is an abnormality detection device that determines that the solenoid valve is abnormal when the operation signal is not equivalent. According to this, even when the electromagnetic valve malfunctions due to the catching of foreign matter as described above, the operation signal of the operating means is a signal corresponding to the stop of the hydraulic actuator, whereas the pilot signal detected by the pressure sensor. Since the pressure signal is a signal corresponding to the driving of the hydraulic actuator, the abnormality can be immediately detected. Accordingly, it is possible to promptly take measures such as stopping the prime mover and stopping all the hydraulic actuators.

[0008]

However, the above-mentioned conventional techniques have the following problems. That is, when foreign matter such as the above-mentioned metal pieces or dust is mixed into the main hydraulic system and enters the control valve, the drive part (spool) of the control valve is caught as in the solenoid valve. It may cause malfunction. In this case, even if the operator operates the operating means so as to stop the hydraulic actuator corresponding to the control valve, and the solenoid valve is in the shut-off position, and the pilot pressure to the control valve is shut off, the spool remains caught. It may be difficult to stop the hydraulic actuator without returning to the neutral position.

At this time, since the pilot pressure signal detected by the pressure sensor and the operation signal output from the operating means are equivalent signals corresponding to the stop of the hydraulic actuator,
It is difficult to detect the abnormality of the main hydraulic system with the above-mentioned conventional technique.

An object of the present invention is to provide an abnormality detecting device for a construction machine capable of detecting an abnormality in the main hydraulic system.

[0011]

(1) In order to achieve the above object, the present invention provides a prime mover, a hydraulic pump driven by the prime mover, an articulated front device, and a front device of the front device. A hydraulic actuator for driving the drive member, an operating means for manually operating the hydraulic actuator, a hydraulic pilot type control valve for controlling the flow of pressure oil from the hydraulic pump to the hydraulic actuator, and an operating means for the operating means. An operation amount detecting means for detecting an operation amount, a solenoid valve for controlling a pilot pressure to the control valve according to the operation amount detected by the operation amount detecting means, and a pilot line from the pilot hydraulic power source to the solenoid valve. A construction machine abnormality detection device provided in a construction machine, comprising: a switching valve capable of connecting and disconnecting the hydraulic actuator. Alternatively, operation detecting means for detecting an operating state of the driven member driven by the hydraulic actuator, switching detecting means for detecting a switching state of the switching valve, the operation amount detecting means, the operation detecting means, and the First determination of abnormality based on the detection result of the switching detection means
And a determining means.

In a hydraulic drive system provided in a construction machine, for example, when foreign matter such as small metal pieces or dust enters the main hydraulic system and gets into the control valve, the drive part (spool) of the control valve is caught. It may cause a malfunction.

In the present invention, first, the operation amount detection means detects the operation amount of the operation means corresponding to the control valve, and the operation detection means detects the operation state of the hydraulic actuator or the driven member corresponding to the control valve. To do. Thereby, for example, the operation amount detecting means detects that the corresponding operating means is not operated by the operator, and the operation detecting means further detects that the hydraulic actuator or the driven member corresponding to the control valve is operating. If detected, there is something wrong with the solenoid valve that should be driven according to the operation amount to control the pilot pressure, or control that should be driven according to the pilot pressure to control the flow of pressure oil to the hydraulic actuator. It can be seen that there is something wrong with the valve. Therefore, in the present invention, the switching detecting means further connects the pilot pipe to the control valve.
The switching state of the switching valve for shutting off is detected. Thereby, for example, when the switching detection means detects that the pilot pressure to the control valve is cut off, the hydraulic actuator or driven member should normally stop if the solenoid valve is abnormal as described above. It is possible to clearly detect that the control valve is malfunctioning, and the first judging means judges that the operation is abnormal. As described above, unlike the conventional structure in which only the abnormality of the pilot circuit can be detected, the abnormality of the main hydraulic system of the construction machine can be detected.

(2) In the above (1), preferably,
In the first determination means, the operation amount detection means detects that the operation means is not operated, and the operation detection means operates the hydraulic actuator or the driven member corresponding thereto. Is detected, and when the switching detection means detects that the switching valve is switched to the shutoff position, it is determined to be abnormal.

(3) In order to achieve the above object, the present invention drives a prime mover, a hydraulic pump driven by the prime mover, an articulated front device, and a driven member of the front device. A hydraulic actuator, a hydraulic pilot type control valve for controlling the flow of pressure oil from the hydraulic pump to the hydraulic actuator, a solenoid valve for controlling the pilot pressure to the control valve, and a pilot hydraulic source to the solenoid valve. And a gate lock device for setting the switching valve to the communicating position by setting the switching valve to the blocking position and the unlocking position to set the switching valve to the communicating position. In a construction machine abnormality detection device provided in a machine, a gate lock detection hand for detecting an operation state of the gate lock device. And an operation detecting means for detecting an operation state of the hydraulic actuator or the driven member driven by the hydraulic actuator, and a second judging means for judging an abnormality based on detection results of the gate lock detecting means and the operation detecting means. With.

In the present invention, the gate lock detecting means detects the operating state of the gate lock device for operating the switching valve for connecting / disconnecting the pilot conduit to / from the control valve, and the operation detecting means corresponds to the control valve. The operating state of the hydraulic actuator or the driven member is detected. Thereby, for example, the gate lock detecting means detects that the operation position of the gate lock device is the lock position and the pilot pressure to the control valve is cut off, and the operation detecting means operates the corresponding hydraulic actuator or driven member. If it is detected that the hydraulic actuator or driven member should stop normally if the solenoid valve is abnormal as in (1) above, the malfunction of the control valve is clearly detected. Therefore, it is determined that the second determination means is abnormal. As described above, the abnormality of the main hydraulic system of the construction machine can be detected.

(4) In the above (3), preferably,
In the second determination means, the gate lock detection means detects that the gate lock device is operated to the lock position, and the operation detection means operates the hydraulic actuator or the driven member. If is detected, it is determined to be abnormal.

(5) In the above item (1) or (3), and preferably, there is provided a prime mover stop control means for stopping the prime mover when the first or second determining means determines an abnormality.

Thus, when an abnormality of the main hydraulic system such as a malfunction of the control valve occurs, the prime mover is automatically stopped, so that the driving of the hydraulic actuator can be surely stopped. Therefore, the work safety of the construction machine can be improved.

(6) In the above (1) or (3), and preferably, there is provided an alarm means for issuing an alarm when the first or second determination means determines an abnormality.

In the present invention, when an abnormality of the main hydraulic system such as a malfunction of the control valve occurs, the alarm means issues an alarm, so that the operator can be immediately notified of the abnormality. In particular, it is possible to inform even when the operator is away from the construction machine, so that the operator can quickly take measures against this abnormality. Therefore, the work safety of the construction machine can be improved.

(7) In the above (1) or (3), and preferably, when the first or second determination means determines that there is an abnormality, an abnormality information storage means is stored.

Thus, for example, at the time of regular maintenance of the construction machine, the maintenance worker can view the abnormality history of the main hydraulic system by connecting a terminal or the like to the abnormality information storage means. As a result, it is possible to perform measures such as intensive maintenance on locations with a high frequency of abnormalities.

Further, there are many cases where malfunctions such as catching of the spool due to foreign matter in the control valve can be corrected immediately after catching foreign matter naturally. Even in such a case, according to the present invention, since the abnormality history is stored in the abnormality information storage means, appropriate maintenance can be performed without overlooking this abnormality. Therefore, the life of the construction machine can be extended.

(8) In any one of the above (1) to (7), and preferably, a state in which a state quantity relating to the operating speed of the hydraulic actuator or the driven member is calculated from the detection result of the operation detecting means. Based on the amount calculation means and the state quantity of the hydraulic actuator or the driven member calculated by the state quantity calculation means, it is determined whether or not the hydraulic actuator is driven by using a predetermined threshold value related to the state quantity. Drive determination means, wherein the drive determination means determines the absolute value of the threshold value of the state quantity in the gravitational force acting direction of the driven member as the absolute value of the threshold value Make it larger than the absolute value of the threshold.

Generally, in a construction machine equipped with a front device such as a hydraulic excavator, even if there is no abnormality in the pilot circuit or the main hydraulic system, due to a slight flow of hydraulic oil through a minute gap in the seal portion, self-weight This may cause the front device to gently descend naturally.

In the present invention, when the drive determining means compares the state quantity of the hydraulic actuator or the driven member with a predetermined threshold value to determine whether it is driven or stopped, the force in the direction of gravity action is determined. The absolute value of the threshold value is more than the absolute value of the threshold value in the direction opposite to the gravity action direction,
For example, the value can be increased by an amount corresponding to the above-mentioned natural descent. As a result, it is possible to prevent the first or second determination means from erroneously determining that the main hydraulic system is abnormal when the front device naturally descends, and it is possible to further improve the determination reliability.

(9) In any one of (1) to (8) above, and preferably further, a rotation detecting means for detecting the presence or absence of rotation of the prime mover is further provided, and the first or second determining means is the above-mentioned. When the rotation detecting means detects the stopped state of the prime mover, the abnormality determination is not performed.

Generally, in a construction machine such as a hydraulic excavator including a hydraulic drive system in which a hydraulic pump is driven by a prime mover, a hydraulic actuator is not driven when the prime mover is stopped. However, as described in (8) above, when the front device descends naturally, or when the control valve is in the neutral shut-off position, the pressure in the conduit between the control valve and the hydraulic actuator is set by the relief valve. When it is detected that the relief valve is operated and the driven member is operating, the first or second determination means can determine that the main hydraulic system is abnormal, even if the main hydraulic system is not abnormal. There is a nature.

Therefore, in the present invention, the presence or absence of rotation of the prime mover is detected by the rotation detecting means, and when the prime mover is stopped, the first or second determining means does not determine abnormality. As a result, it is possible to prevent erroneous determination of abnormality while the prime mover is stopped, and it is possible to further improve the reliability of determination.

(10) In any one of (1) to (9) above, and preferably, the operation detecting means is an angle sensor provided on the driven member driven by the hydraulic actuator.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an abnormality detecting device for a construction machine according to the present invention will be described below with reference to the drawings. First, a first embodiment of an abnormality detection device for a construction machine according to the present invention will be described below with reference to FIGS. 1 to 5.

FIG. 1 is a side view showing the overall structure of a hydraulic excavator provided with a first embodiment of a construction machine abnormality detection apparatus according to the present invention. In FIG. 1, reference numeral 1 is a relatively small so-called offset type hydraulic excavator, and this hydraulic excavator 1 is a traveling means including left and right endless track crawler tracks (crawler) 2L, 2R (however, in FIG. An undercarriage 3 having a track crawler track 2R only) and an upper revolving superstructure 4 rotatably mounted on an upper part of the undercarriage 3
A revolving frame 5 which forms the foundation lower structure of the upper revolving superstructure 4, an articulated front device 6 connected to a substantially central portion of the upper revolving superstructure 4, and an operation provided on the revolving frame 5. A chamber 7 and an upper cover 8 that covers a portion of the upper revolving structure 4 other than the driver's cab 7 are provided.

The front device 6 has a lower boom 9 whose base end is connected to a substantially central portion of the revolving frame 5 so as to be vertically rotatable (so as to be able to lift and lower), and a left and right ends of the lower boom 9 at the tip thereof. Upper boom 10 rotatably connected in a direction, an arm cylinder bracket 11 rotatably connected to the tip of the upper boom 10 in the left-right direction, and a tip end of the arm cylinder bracket 11 in a vertical direction. An arm 12 rotatably connected, a bucket 13 rotatably connected to the tip of the arm 12 in the vertical direction, a stay 14 (described later) that connects the lower boom 9 and the arm cylinder bracket 11 to each other. 2), a boom hydraulic cylinder 15 for driving the lower boom 9, and the arm cylinder bracket 11 together with the left boom 9 on the left side. Hydraulic cylinders for offset driving the upper boom 10 is pivotally connected to the direction 1
6, an arm hydraulic cylinder 17 for driving the arm 12, and a bucket hydraulic cylinder 18 for driving the bucket 13.

By configuring the front device 6 as described above, as shown in FIG. 2, the offset hydraulic cylinder 1 is provided.
When 6 extends, the upper boom 10 turns in the A direction,
When the offset hydraulic cylinder 16 contracts, the upper boom 10 turns in the B direction. At this time, the stay 1
4, the upper boom 10 turns with the arm cylinder bracket 11 always facing the front of the hydraulic excavator 1 (rightward in FIG. 2). That is, while keeping the arm cylinder bracket 11, the arm 12 and the bucket 13 connected to the front end side of the arm cylinder bracket 11 in the front device 6 in the front direction of the hydraulic excavator 1, the upper boom 10 is moved in the left-right direction. You can turn.

Returning to FIG. 1, the front device 6 includes a connecting portion between the upper swing body 4 and the lower boom 9, a connecting portion between the lower boom 9 and the upper boom 10, and a connecting portion between the arm cylinder bracket 11 and the arm 12. Further, a boom angle sensor 19, an offset angle sensor 20, and an arm angle sensor 21 are provided respectively. These boom angle sensor 19, offset angle sensor 20,
And the angle sensor 21 for the arm, the vertical relative angle of the lower boom 9 to the upper revolving structure 4, the horizontal relative angle of the upper boom 10 to the lower boom 9, and the vertical relative angle of the arm 12 to the arm cylinder bracket 11. It can be detected.

Although not shown, the upper cover 8 has an engine 22 (see FIG. 3 to be described later) inside thereof.
The hydraulic pump 23 driven by the engine 22 (see FIG. 3, which will be described later), a fuel tank for storing the fuel of the engine 22, and a hydraulic oil tank that serves as a pressure oil source for the hydraulic pump 23 are housed.

In the hydraulic excavator 1 constructed as described above, the left and right crawler tracks 2L and 2R, the upper swing body 4, the lower boom 9, the upper boom 10, and the arm 1 described above.
The bucket 2 and the bucket 13 constitute a driven member driven by a hydraulic drive device provided in the hydraulic excavator 1. The boom hydraulic cylinder 15, the offset hydraulic cylinder 16, the arm hydraulic cylinder 17, and the bucket hydraulic cylinder 1 for driving the driven members.
The hydraulic actuator including 8 and the like is driven by the hydraulic drive device. The details of this hydraulic drive device will be described below by taking the boom hydraulic cylinder 15 as an example.

FIG. 3 is a hydraulic circuit diagram showing the essential structure of the boom hydraulic cylinder 15 in the hydraulic drive system of the hydraulic excavator 1. In FIG. 3, the hydraulic drive system is driven by the engine 22, the hydraulic pump 23 that is driven by the engine 22 and supplies pressure oil to the boom hydraulic cylinder 15, and is driven by the engine 22 similarly to the hydraulic pump 23. A pilot pump 24 serving as a supply source of pilot pressure, a boom control valve 25 for controlling pressure oil supplied from the hydraulic pump 23 to the boom hydraulic cylinder 15, a controller 26, and an operation unit provided in the cab 7. Hydraulic cylinder for boom 1
And an operating lever device 27 for manually operating 5.

The boom control valve 25 is
A three-position switching valve of the center closed type having pilot drive parts 25a and 25b at both ends.
Is connected to the discharge pipe line 28. Pilot drive 2
When 5a is driven by the pilot pressure, the boom control valve 25 switches to the switching position 25A, and the pressure oil from the hydraulic pump 23 is guided to the boom hydraulic cylinder 15 via the extension side pressure oil supply conduit 29. The boom hydraulic cylinder 15 is adapted to extend. On the other hand, when the pilot drive unit 25b is driven by the pilot pressure, the boom control valve 25 is switched to the switching position 25B, and the pressure oil from the hydraulic pump 23 passes through the compression side pressure oil supply conduit 30 to the boom hydraulic cylinder. 15
The boom hydraulic cylinder 15 is shortened by being guided to.

In this way, the boom control valve 2
The pilot pressure for controlling the drive of No. 5 is
The pilot pressure generated by the pump 24 is applied to the solenoid valves 31, 32.
It was decompressed with. These solenoid valves 31, 32 are
Electromagnetic provided with solenoid drive units 31a and 32a, respectively
It is a switching valve. In the solenoid drive parts 31a and 32a
Is an actuator control provided in the controller 26.
Expansion control signal S from section 33_B1(Hydraulic cylinder for boom
(Corresponding to the drive of the extension direction of the cable 15), the shortening control signal S_B2
(Compatible with driving the boom hydraulic cylinder 15 in the direction of shortening)
Each has a solenoid driven by
The magnetic valves 31 and 32 have their expansion control signals S _B1Or shortening
Signal S_B2Is controlled by.

The operation lever device 27 includes the operation lever 2
7a and a potentiometer 27b. The potentiometer 27b outputs an operation signal M corresponding to the operation amount of the operation lever 27a to the actuator control section 33 of the controller 26.

That is, the actuator controller 33
Is an expansion control signal S _B1 (or a contraction control signal S _B in accordance with the operation signal M input from the potentiometer 27b).
_B2 ) is output to the solenoid valve 31 (or the solenoid valve 32). As a result, the solenoid valve 31 (or the solenoid valve 32) is connected to the communication position 3
1A (or the communication position 32A), and the pilot pressure is reduced according to the extension control signal S _B1 (or the contraction control signal S _B2 ). In this way, the flow direction and flow rate of the pressure oil supplied from the hydraulic pump 23 to the boom hydraulic cylinder 15 by the pilot pressure generated by the solenoid valves 31 and 32 are reduced by the boom control valve 25, and the above-mentioned operation is performed. The boom hydraulic cylinder 15 can be driven according to the operation amount of the lever 27a.

When the operation lever 27a is not operated, the potentiometer 27b turns off the output of the operation signal M. Therefore, the hydraulic actuator control unit 33 outputs the extension control signal S _B1 and the contraction control signal S _B2 . Is also turned off, and the solenoid valves 31 and 32 are respectively spring 31
The urging forces of b and 32b return to the blocking positions 31B and 32B. Therefore, the boom control valve 25 also returns to the neutral position 25C by the urging force of the springs 25c and 25d,
The boom hydraulic cylinder 15 is adapted to stop.

At this time, the relief valve 34 and the check valve 3 are provided in the conduit 29a branched from the extension side pressure oil supply conduit 29.
5a are connected in parallel, and a check valve 35b is connected to the pipeline 30a branched from the compression side pressure oil supply pipeline 30. The relief valve 34 changes the value of the relief pressure that limits the maximum value of the pressure in the extension side pressure oil supply pipe 29,
The relief valve 34 is set by the urging force of a spring 34a provided in the relief valve 34. As a result, as described above, when the boom control valve 25 is in the neutral position and the boom hydraulic cylinder 15 is stopped, for example, a relatively large load in the gravity direction is generated in the lower boom 9, and the extension side pressure oil supply conduit 29 is provided. If the pressure exceeds the relief pressure, the relief valve 34 operates to prevent damage to the extension side pressure oil supply line 29 due to overload. In such a case, the hydraulic oil flows due to the operation of the relief valve 34, the boom hydraulic cylinder 15 shortens and the lower boom 9 is slightly lowered.

On the other hand, a switching valve 37 is connected to the discharge conduit 36 of the pilot pump 24. The switching valve 37 is normally connected to the communication position 37 by the urging force of the spring 37a.
It switches to A and guides the discharge pressure of the pilot pump 24 to the solenoid valves 31 and 32. The switching valve 37 is provided with a solenoid drive unit 37b. When the solenoid drive unit 37b receives a cutoff signal _SP2 from a pilot pressure cutoff control unit 38 provided in the controller 26, the changeover valve 37 is operated. Switching to the blocking position 37B,
The pilot pressure by the pilot pump 24 is cut off (details will be described later).

A relief valve 40 is connected to a conduit 39 branched from the discharge conduit 36 of the pilot pump 24, and the relief valve 40 limits the maximum discharge pressure of the pilot pump 24 by the urging force of a spring 40a. It is designed to set the pressure value.

The hydraulic excavator 1 having the above-described structure
In the present invention, the most significant feature of the present invention is that when the operation lever is not operated, it is detected by the angle sensor that the driven member that constitutes the front device is operating, and further, it corresponds to the driven member. When the pilot pressure to the control valve is shut off, it is determined that the main hydraulic system of the hydraulic drive system is abnormal. The detailed structure of the abnormality detecting device of the present invention will be described below by taking the lower boom 9 as an example of the driven member forming the front device.

As shown in FIG. 3, the controller 26 has an abnormality / motion information processing section 41 in addition to the actuator control section 33 and the pilot pressure cutoff control section 38.
An angular velocity calculation unit 42, an alarm device control unit 43, and an abnormality / motion information storage unit 44. In addition, the abnormality / motion information processing unit 41 includes an output unit 41a.

FIG. 4 is a flow chart showing the control contents of the abnormality / motion information processing unit 41. In FIG. 4, the abnormality / motion information processing unit 41 starts this control flow when the controller 26 is powered on, and repeats this flow at a predetermined cycle until the power is turned off. There is. When the power is turned on, the abnormality / motion information processing unit 41 starts this flow regardless of whether the engine 22 is driven or stopped. First, in step 10, the operation signal M from the potentiometer 27b of the operation lever device 27 is input, and the process proceeds to the next step 20.

At step 20, it is judged based on the operation signal M inputted at step 10 whether or not the operation lever 27a is operated. If the operation lever 27a is operated, the determination is not satisfied, and the abnormality / motion information processing unit 41 ends this flow. If the operation lever 27a has not been operated, the determination is satisfied, and the routine goes to the subsequent Step 30.

In step 30, the angular velocity calculation section 42 is used.
Inputs the angular velocity V of the lower boom 9 calculated on the basis of the angle A detected by the boom angle sensor 19, and proceeds to the next step 40.

In step 40, it is determined whether or not the lower boom 9 is being driven (forced driving by an external driving force). Specifically, as shown in FIG.
It is determined whether the angular velocity V of the lower boom 9 input at 0 is larger than the threshold value X in the raising direction or smaller than the threshold value Z in the lowering direction. The threshold value X is a predetermined value indicating that the lower boom 9 is being driven upward due to an abnormal operation of the boom hydraulic cylinder 15 when the angular velocity V of the lower boom 9 is greater than the threshold value X. Similarly, when the angular velocity V of the lower boom 9 is smaller than the threshold value Z, the threshold Z is driving the lower boom 9 downward due to an abnormal operation of the boom hydraulic cylinder 15. It is a predetermined value indicating that. These threshold values X and Z are, for example, previously recorded in the controller 26 (or set and input by an appropriate external input means). If the angular velocity V of the lower boom 9 is outside the abnormal operation range (Z ≦ V ≦ X), the determination is not satisfied and the routine goes to Step 50.

In step 50, it is judged whether or not the lower boom 9 is naturally descending. Specifically, as shown in FIG. 5, it is determined whether the angular velocity V input in step 30 is smaller than the threshold value Y. When the angular velocity V of the lower boom 9 is smaller than the threshold value Y, the threshold value Y is small when the lower boom 9 passes through a minute gap in the seal portion of the boom control valve 25. It is a predetermined value indicating that it is gradually and naturally lowered due to its own weight due to flow or the like, and is recorded in advance in the controller 26 (or set and input by an appropriate external input means). If the angular velocity V is greater than or equal to the threshold value Y, the determination is not satisfied, and the abnormality / motion information processing unit 41 ends this flow. If the angular velocity V is smaller than the threshold value Y, it is regarded as a natural descent, the determination is satisfied, and the routine proceeds to Step 140 described later. If the angular velocity V is greater than or equal to the threshold value Y, the angular velocity V is in the stationary range (Y ≦ V ≦
X), and therefore the lower boom 9 is considered to be normally stationary, and the abnormality / motion information processing unit 41 ends this flow.

If the angular velocity V is larger than the threshold value X or smaller than the threshold value Z in the previous step 40, the determination is satisfied and the routine goes to step 60.

In step 60, the engine start signal S _S output from the generator 45 (see FIG. 3) installed in the engine 22 is input, and the process proceeds to the next step 70.

In step 70, it is determined whether the engine 22 is driven by the engine start signal S _S input in step 60. Specifically, it is determined whether the engine starting signal S _S which is a voltage signal is higher than the threshold value Hi or lower than the threshold value Lo. This threshold value Hi is a predetermined voltage value indicating that the engine is starting when the engine start signal S _S has a value larger than this threshold value Hi, and the threshold value Lo
Is a predetermined voltage value indicating that the engine is stopped when the engine start signal S _S is a value smaller than the threshold value Lo, and these threshold values Hi and Lo are previously stored in the controller 26, for example. It is recorded (or set and input by an appropriate external input means). If the engine start signal S _S is larger than the threshold value Ho, it is considered that the engine 22 is being driven, the determination is satisfied, and the routine goes to the subsequent Step 80.

In step 80, the cutoff control signal S _P1 is output to the pilot pressure cutoff control unit 38, and this pilot pressure cutoff control unit 38 outputs the cutoff signal S _P2 to the switching valve 37. As a result, as described above, the switching valve 37 is switched to the shutoff position 37B, and the pilot pressure by the pilot pump 24 is shut off.

In the next step 90, the angular velocity calculation unit 42
Again inputs the angular velocity V calculated based on the angle A detected by the boom angle sensor 19, and in the next step 100, it is determined whether the angular velocity V is within the abnormal operation range (V <Z or V> X). judge. If the angular velocity V is within the abnormal operation range, the determination is satisfied, it is determined in the next step 110 that the main hydraulic system is abnormal, and the routine proceeds to the next step 130. In addition,
In step 100, the angular velocity V falls outside the abnormal operation range (Z ≦
If V ≦ X), the determination is not satisfied and the routine proceeds to step 120, where it is determined that the pilot circuit is abnormal, and the routine proceeds to next step 130.

In step 130, the output unit 41a provided in the abnormality / motion information processing unit 41 outputs an alarm control signal S _A1 to the alarm device control unit 43, which causes the alarm device control unit 43 to output the alarm signal S. _A2 alarm buzzer 4
6 (see FIG. 3). As a result, the alarm buzzer 46 sounds the buzzer. Then, the process proceeds to step 160. If the angular velocity V is smaller than Y in step 50, the step 1 is performed as described above.
In step 140, it is determined to be a natural descent, and the process proceeds to the next step 160. If the engine 22 is stopped in the previous step 70, the determination is not satisfied and the routine proceeds to step 150, where it is determined that the relief valve 34 is in operation in this step 150,
Move to next step 160.

In step 160, the previous step 11
0, step 120, step 140, or step 1
"Main hydraulic system abnormality", "Pilot circuit abnormality", "Spontaneous descent", or "Relief valve operation" determined in 50
Of the abnormality / operation information history of the output unit 41a stores the storage signal S _M
Is output to the abnormality / operation information storage unit 44. The abnormal / motion information history is stored in the abnormal / motion information storage unit 44, and the abnormal / motion information processing unit 41 ends this flow.

Although the lower boom 9 among the driven members constituting the front device 6 has been described above as an example,
The upper boom 10 and the arm 12 also have the same configuration.

In the above, the hydraulic excavator 1 constitutes the construction machine according to the claims, and the lower boom 9,
The upper boom 10 and the arm 12 constitute a driven member of the front device, and include a boom hydraulic cylinder 15, an offset hydraulic cylinder 16, and an arm hydraulic cylinder 1.
7 is a hydraulic actuator for driving the driven member of the front device, and the boom control valve 25 is
A hydraulic pilot type control valve for controlling the flow of pressure oil from the hydraulic pump to the hydraulic actuator is configured. Further, the operation lever device 27 constitutes an operating means for manually operating the hydraulic actuator, and the potentiometer 27b constitutes an operation amount detecting means for detecting an operation amount of the operating means.

The boom angle sensor 19, the offset angle sensor 20, and the arm angle sensor 21 are
Abnormality / motion information processing is configured by configuring motion detection means for detecting the motion state of the hydraulic actuator or a driven member driven by this hydraulic actuator, and also configuring an angle sensor provided on the driven member driven by the hydraulic actuator. Step 80 in the flow shown in FIG. 4 performed by the section 41 constitutes a switching detection means for detecting the switching state of the switching valve, and step 110 is abnormal based on the detection results of the operation amount detection means, the movement detection means, and the switching detection means. It constitutes a first determination means for determining.

Further, the angular velocity V constitutes a state quantity relating to the operating speed of the hydraulic actuator or the driven member, and the angular velocity calculating section 42 constitutes a state quantity calculating means for calculating the state quantity, and abnormality / motion information processing is performed. Step 40 in the flow shown in FIG. 4 performed by the unit 41 constitutes drive determination means for determining whether or not the hydraulic actuator is driven by using a predetermined threshold value regarding the state quantity.

Further, the engine 22 constitutes a prime mover, the generator 45 constitutes a rotation detecting means for detecting the presence or absence of rotation of the prime mover, and the abnormality / operation information storage unit 44 stores abnormality information storage means for storing abnormality information. The alarm buzzer 46 constitutes an alarm means for issuing an alarm.

Next, the operation and action of the first embodiment of the abnormality detecting apparatus for the construction machine of the present invention having the above-mentioned structure will be described below. When the controller 26 is powered on and the operator operates the operation lever 27a to perform the work,
The motion information processing unit 41 repeats steps 10 to 20 shown in FIG.

On the other hand, when the operator has not operated the operation lever 27a, the determination at step 20 in FIG. 4 is satisfied, and the routine goes to step 30. Here, the angle A is detected by the boom angle sensor 19 provided in the lower boom 9, for example, and is input to the angular velocity calculation unit 42. The angular velocity calculation unit 42 calculates the angular velocity V of the lower boom 9 based on the input angle A, and in Step 30, the angular velocity V is input to the abnormality / motion information processing unit 41.

In this way, the abnormality / motion information processing unit 41
The angular velocity V input to is determined based on the determination criteria shown in FIG. At this time, the angular velocity V is in the stationary range (Y ≦ V ≦
If it is within X), the lower boom 9 is considered to be normally stationary, the determinations in step 40 and step 50 in FIG. 4 are not satisfied, and steps 10 to 50 are repeated.

On the other hand, the angular velocity V is in the natural descending range (Z≤V <
If it is within Y), the determination at step 50 in FIG. 4 is satisfied, and at the next step 140, it is determined that the lower boom 9 naturally descends regardless of whether the engine 22 is driven or stopped. This determination result is obtained in the next step 160.
It is stored in the abnormality / motion information storage unit 44 as motion information “natural descent”.

On the other hand, the angular velocity V is in the abnormal operation range (V <Z,
Or, if V> X), the possible causes differ depending on whether the engine 22 is being driven or stopped. That is, when the engine 22 is being driven, as a cause thereof, there is a configuration related to the pilot circuit, such as abnormality of the solenoid valves 31 and 32 or abnormality of the controller actuator control unit 33 that outputs a control signal to the solenoid valves 31 and 32. It is conceivable that this is either an abnormality or an abnormality of the main hydraulic system, such as a spool malfunction due to foreign matter being caught in the control valve 25.

At this time, in the present embodiment, the determination in step 70 in FIG. 4 is satisfied, and in the next step 80, the abnormality / motion information processing section 41 controls the pilot pressure cutoff control section 38 to cause the switching valve to operate. 37 is a blocking position 37B
The pilot pressure by the pilot pump 24 is shut off. Next, Step 90 and Step 10
At 0, the angular velocity V of the lower boom 9 is input again, and the determination is performed, as in steps 30 and 40. At this time, if the angular velocity V is outside the operation abnormality range (Z ≦ V ≦ X), it means that the operation abnormality of the lower boom 9 has been improved by cutting off the pilot pressure, and the former pilot of the above two causes. It can be regarded as an abnormality in the configuration related to the circuit. Therefore, the determination in step 100 is not satisfied, and the process proceeds to step 120, and this step 120
At, it is determined that the pilot circuit is abnormal. Based on this determination result, in the next step 130, the abnormality / motion information processing unit 41 controls the alarm device control unit 43 to issue the alarm buzzer 46. Thereafter, this determination is stored in the abnormality / operation information storage unit 44 as abnormality information "pilot circuit abnormality" in the next step 160.

On the other hand, when the angular velocity V input after shutting off the pilot pressure is within the abnormal operation range (V <Z or V> X), even if the pilot pressure is shut off, the abnormal operation of the lower boom 9 is not improved. It turns out that the pilot circuit is not abnormal. That is, it can be regarded as an abnormality of the main hydraulic system. Therefore, step 10
The determination of 0 is satisfied, and it is determined in step 110 that the main hydraulic system is abnormal. Based on this judgment result, the next step 1
An alarm buzzer 46 is issued at 30 and this determination is stored in the abnormality / operation information storage unit 44 as abnormality information "main hydraulic system abnormality" in the next step 160.

In this way, according to the present embodiment,
Abnormal operation of solenoid valves 31, 32 or these solenoid valves 31, 3
Unlike the conventional structure which can detect only the abnormality of the pilot circuit due to the abnormality of the actuator control unit 33 for controlling the control unit 2, the abnormality of the main hydraulic system due to the stick of the boom control valve 25 can be clearly detected. In addition, by issuing an alarm buzzer when the "pilot circuit abnormality" or "main hydraulic system abnormality" is determined, the operator can be immediately notified even when the operator is away from the hydraulic excavator 1. Can be notified of abnormalities. As a result, the operator can quickly take measures against these abnormalities, and thus the operational safety of the hydraulic excavator 1 can be improved.

Further, by storing the abnormality information such as "pilot circuit abnormality" and "main hydraulic system abnormality" in the abnormality / operation information storage section 44, for example, at the time of periodic maintenance of the hydraulic excavator 1, the maintenance worker can perform the above-mentioned operation. Similarly to the above, for example, the terminal 47 (see FIG. 3) can be used to view it as the abnormality information history. As a result, it is possible to perform measures such as intensive maintenance on locations with a high frequency of abnormalities. Further, for example, the malfunction of the boom control valve 25 due to the biting of a foreign substance such as a stick is often corrected immediately after the foreign substance is naturally caught. Even in such a case, according to the present embodiment, it is surely stored in the abnormality / operation information storage unit 44 as "main hydraulic system abnormality". Therefore, by looking at the abnormality information history, it is possible to appropriately check the abnormality. Maintenance can be performed. Therefore, the life of the hydraulic excavator 1 can be extended.

On the other hand, the angular velocity V is in the abnormal operation range (V
<Z or V> X), when the engine 22 is stopped, since the hydraulic pump 23 is not driven, the boom hydraulic cylinder 15 is driven by the pressure oil of the hydraulic pump 23. It cannot happen. Here, the reason why the lower boom 9 operates while the engine 22 is stopped is that the above-described spontaneous descent or the above-mentioned relief valve 3 is performed.
It is conceivable that there will be a descent due to the operation of 4. At this time, the descent angular velocity V due to the operation of the latter relief valve 34 tends to be relatively larger than the natural descent angular velocity V. Therefore, when the angular velocity V of the lower boom 9 is within the abnormal operation range (V <Z or V> X) as in this case, the relief valve 3
4 can be considered activated. Therefore, the determination in step 70 is not satisfied, and the process proceeds to step 150,
In step 150, it is determined that the relief valve is operating. This determination is stored in the abnormality / motion information storage unit 44 as motion information “relief valve actuation” in the next step 160.

As described above, according to the present embodiment, the natural lowering of the lower boom 9 and the lowering due to the operation of the relief valve 34 can be detected as normal operation without abnormality. Thereby, the reliability of the determination of the abnormality / motion information processing unit 41 can be improved. Further, by storing the operation information such as “natural descent” and “relief valve operation” in the abnormality / operation information storage unit 44, for example, a maintenance worker connects the terminal 47 to the controller 26 at the time of maintenance or the like. It can be seen as a history of motion information. Thereby, for example, the control valve 2
It is possible to understand that the seal of No. 5 is deteriorated, a relatively large load is generated on the lower boom 9 while the engine 22 is stopped, and appropriate measures can be taken before an abnormality occurs. Therefore, the life of the hydraulic excavator 1 can be extended.

Next, a second embodiment of the abnormality detecting apparatus for a construction machine according to the present invention will be described below with reference to FIGS. 6 and 7. In this embodiment, the engine is automatically stopped when the abnormality of the main hydraulic system is determined. FIG. 6 is a hydraulic circuit diagram showing a main configuration of a boom hydraulic cylinder 15 in the hydraulic drive system of the hydraulic excavator 1 including the second embodiment of the abnormality detecting device for a construction machine according to the present invention. is there. In FIG. 6, the same parts as those in FIG. 3 according to the first embodiment of the present invention described above are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 6, the controller 26 'includes an engine stop control unit 50 and the engine stop control unit 50.
And an abnormality / motion information processing unit 41 'having an output unit 41'a further added with the control function of. _Reference numeral 51 is a fuel injection device for injecting fuel into the engine 22, and when the stop signal S _EN2 is input from the engine stop control unit 50, the injection of fuel into the engine 22 is stopped. .

FIG. 7 shows the abnormality / motion information processing unit 41 '.
3 is a flowchart showing the control contents of FIG. In FIG. 7, when the power of the controller 26 'is turned on, the abnormality / motion information processing unit 41' starts this control flow, and repeats this flow at a predetermined cycle until the power is turned off. Has become. When the power is turned on, the abnormality / operation information processing unit 41 'starts this flow regardless of whether the engine 22 is driven or stopped. In FIG. 7, step 210 to step 31
0 is the same as step 10 to step 110 of FIG. 4 in the first embodiment of the present invention described above, and the abnormality / motion information processing unit 41 'inputs the operation signal M from the operation lever 27a to operate. If the lever 27a is not operated, the angular velocity V of the lower boom 9 is input, and this angular velocity V is shown in FIG.
If the operation abnormality range (V <Z or V> X) is within, the engine start signal S _S is input, and if the engine 22 is being driven, the switching valve 37 shuts off the pilot pressure. Similarly, if the angular velocity V of the lower boom 9 is within the operation abnormality range, it is determined that the main hydraulic system is abnormal.

In the next step 320, the output unit 4
1'a sends a stop control signal S to the engine stop control unit 50.
Output _EN1 . The engine stop control unit 50, to which the stop control signal S _EN1 is input, outputs the stop signal S _EN2 to the fuel injection device 51, whereby the fuel injection device 51.
Stops the injection of fuel into the engine 22. In this way, the engine 22 is stopped.

The following steps 340 to 370 are
This is the same as Step 130 to Step 160 in FIG. 4 described above, and is “main hydraulic system abnormality” or “pilot circuit abnormality”.
If it is determined that the alarm buzzer is issued and stored as an abnormality history in the abnormality / operation information storage unit 44, and if it is determined to be "natural descent" or "relief valve operation", the abnormality / operation information storage unit 44 Only the operation history is stored.

Although the lower boom 9 among the driven members constituting the front device 6 has been described above as an example,
Similar to the above-described first embodiment, the upper boom 10
Also, the arm 12 has the same configuration.

In the above, the engine stop control unit 50
Constitutes a prime mover stop control means for stopping the prime mover according to each of the claims, and the abnormality / motion information processing unit 41 '.
Step 240 in the flow shown in FIG. 7, which is performed by the above, constitutes drive determination means for determining whether or not the hydraulic actuator is driven using a predetermined threshold value regarding the state quantity.

According to the second embodiment of the construction machine abnormality detecting apparatus of the present invention having the above-mentioned structure, when the abnormality / motion information processing unit 41 'determines that the main hydraulic system is abnormal, the engine stop control unit is operated. The engine 22 can be automatically stopped by the control of 50. As a result, the driving of the hydraulic actuator including the boom hydraulic cylinder 15 can be reliably stopped. Therefore, the operational safety of the hydraulic excavator 1 can be improved.

Next, a third embodiment of the abnormality detecting apparatus for a construction machine according to the present invention will be described below with reference to FIGS. 8 and 9. In this embodiment, an abnormality of the main hydraulic system is detected based on the operation position of the gate lock lever and the operating state of the driven member. FIG. 8 is a hydraulic circuit diagram showing a main configuration of a boom hydraulic cylinder 15 in a hydraulic drive system of a hydraulic excavator 1 having a third embodiment of the construction machine abnormality detecting apparatus according to the present invention. is there. In addition,
In FIG. 8, the same parts as those in FIG. 3 in the first embodiment of the present invention described above are designated by the same reference numerals and the description thereof will be omitted.

In FIG. 8, the controller 26 ″ controls the gate lock lever 60 by a gate lock signal L described later.
pilot with an abnormal-operation information processing unit 41 'having the function of detecting the operating position of a, that is input to the gate lock signal L a function to switch to outputting the interrupting signal S _P2 into the switching valve 37 shut-off position 37B A gate lock lever device 60 is provided in the cab 7. The gate lock lever device 60 includes a lock lever 60a and a switch 60b. The switch 60b is adapted to output a gate lock signal L corresponding to the operation position of the lock lever 60a to the abnormality / motion information processing unit 41 ″ and the pilot pressure cutoff control unit 38 ′. At this time,
When the lock lever 60a is in the lock position, the switch 6
0b outputs a gate lock signal L to the pilot pressure cutoff control section 38 ', and the pilot pressure cutoff control section 38' which receives the gate lock signal L outputs a cutoff signal S _P2 to the switching valve 37, thereby switching. Valve 37 is in shut-off position 3
It switches to 7B to shut off the pilot pressure. On the other hand, when the lock lever 60a is in the unlocked position, the gate lock signal L output from the switch 60b to the pilot pressure cutoff control section 38 'is turned off, whereby the pilot pressure cutoff control section 38' transfers to the switching valve 37. The cutoff signal _SP2 that is output is also OFF,
The switching valve 37 returns to the communication position 37A.

FIG. 9 shows the abnormality / motion information processing unit 41 ".
3 is a flowchart showing the control contents of FIG. In FIG. 9, the abnormality / motion information processing unit 41 ″ starts this control flow when the controller 26 ″ is powered on, and repeats this flow at a predetermined cycle until the power is turned off. Has become. When the power is turned on, the abnormality / motion information processing unit 41 ″ starts this flow regardless of whether the engine 22 is driven or stopped. First, at step 410, the gate lock lever device 6 is started.
The gate lock signal L from the 0 switch 60b is input, and the routine goes to the subsequent Step 420.

In step 420, it is determined whether or not the operation position of the gate lock lever 60a is the lock position based on the gate lock signal L input in the above step 410. If the gate lock lever 60a is in the lock position and the pilot pressure is cut off, the determination is satisfied, and the routine goes to the subsequent Step 430.

Steps 430 to 470 are the same as those described above.
Step 30 to Step of FIG. 4 in one embodiment of
Similar to 70, the input angular velocity V of the lower boom 9 is
Within the abnormal operation range (V <Z or V> X) shown in FIG.
Engine start signal S _SAnd the engine 22
Determine if it is driving. Engine 22 drive
If so, the determination at step 470 is satisfied and the next
Move to step 480.

In step 480, the abnormality / motion information processing unit 41 "determines that the main hydraulic system is abnormal.

The following steps 490 to 520
Similar to steps 130 to 160 in FIG. 4 described above, when it is determined that "main hydraulic system abnormality", an alarm buzzer is issued and stored in the abnormality / operation information storage unit 44 as an abnormality history, and "natural" is displayed. "Descent" or "Relief valve actuation"
If it is determined that the operation history is stored in the abnormality / operation information storage unit 44, only the operation history is stored.

In the above description, the lower boom 9 among the driven members constituting the front device 6 has been described as an example.
Similar to the first and second embodiments described above, the upper boom 10 and the arm 12 also have the same configuration.

In the above, the gate lock lever device 6
Reference numeral 0 denotes a gate lock device that sets the switching valve to the shut-off position and the unlock position to set the switching valve to the communication position by setting the switch to the lock position described in the claims, and the switch 60b is a gate lock device. A gate lock detecting means for detecting an operation state of the device is configured.

Further, step 480 in the flow shown in FIG. 9 performed by the abnormality / motion information processing unit 41 ″ constitutes second judgment means for judging abnormality based on the detection results of the gate lock detection means and the motion detection means, Step 440
A drive determination unit that determines whether or not the hydraulic actuator is driven using a predetermined threshold value regarding the state quantity is configured.

Next, the operation and action of the third embodiment of the construction machine abnormality detection device of the present invention having the above-mentioned structure will be described below. When the gate lock lever 60a is in the unlocked position, for example, when the controller 26 ″ is powered on and the operator operates the operation lever 27a to perform the work, the abnormality / motion information processing unit 41 ″ is shown in FIG. Steps 410 to 420 shown therein are repeated.

On the other hand, when the operator finishes the work and leaves the hydraulic excavator 1, for example, the gate lock lever 60a is normally operated to the lock position. As a result, the switching valve 37 is switched to the shutoff position 37B and the pilot pressure is shut off. That is, the determination at step 420 in FIG. 9 is satisfied, and the routine goes to step 430.

Thereafter, steps 430 and 440 are performed.
Then, similarly to the above-described first embodiment, the angular velocity V of the lower boom 9 is input and is determined based on the determination criteria shown in FIG. Here, the angular velocity V is in the abnormal operation range (V <Z or V
> X), since the pilot pressure is shut off by the gate lock lever in step 420, the solenoid valves 31, 32 or these solenoid valves 31, 32 are shut off.
It can be seen that this is not an abnormality in the configuration related to the pilot circuit such as an abnormality in the actuator control unit 33 that controls the. That is, it is found that the abnormality is caused in the main hydraulic system or the operation of the relief valve.

Therefore, in the next steps 460 and 470, it is determined whether the engine 22 is being driven. Here, as described above, it can be considered that the relief valve is operating when the engine 22 is stopped, and that the main hydraulic system is abnormal when the engine 22 is being driven. Therefore, when the engine 22 is being driven, the determination at step 470 is satisfied, and at the next step 480, it is determined that the main hydraulic system is abnormal. Based on this determination result, the alarm buzzer 46 is issued in the next step 490, and the next step 5
At 20, the abnormality / operation information storage unit 44 stores the abnormality information “main hydraulic system abnormality”.

As described above, according to this embodiment, it is possible to clearly detect the abnormality of the main hydraulic system as in the case of the first embodiment.

In the above-described first to third embodiments of the abnormality detecting device for a construction machine according to the present invention,
Boom angle sensor 19, offset angle sensor 20, and arm angle sensor 2 used as motion detecting means.
For No. 1, the existing interference prevention sensor may be used without being newly provided. Thereby, cost reduction can be achieved.

Further, in the first to third embodiments, the operating state of the driven member such as the lower boom 9 is detected by the angle sensor, but the present invention is not limited to this. For example, a known stroke sensor may be used. The stroke speed of a hydraulic actuator (for example, the boom hydraulic cylinder 15) that drives the driven member may be detected. That is, it is sufficient if the operating state of the driven member can be detected.

Further, although the alarm buzzer 46 is used as the alarm device in the first to third embodiments, the alarm device is not limited to this and may be a device such as an alarm lamp that visually indicates an abnormality. That is, it is sufficient if the operator can be notified of the abnormality.

[0104]

According to the first aspect of the present invention, the operation amount detecting means detects that the operating means is not operated, and the operation detecting means operates the hydraulic actuator or the driven member corresponding thereto. Is detected, and the switching detection means switches the switching valve to the shut-off position and shuts off the pilot pressure to the corresponding control valve, the first determination means determines that there is an abnormality. . Thereby, the abnormality of the main hydraulic system of the construction machine can be detected.

According to the third aspect of the present invention, the gate lock detecting means detects that the gate lock device is operated to the lock position, and the operation detecting means further corresponds to the hydraulic actuator or the driven member. Is detected to be abnormal by the second determining means. Thereby, the abnormality of the main hydraulic system of the construction machine can be detected.

[Brief description of drawings]

FIG. 1 is a side view showing an overall structure of a hydraulic excavator including a first embodiment of an abnormality detection device for a construction machine according to the present invention.

FIG. 2 is a top view showing the turning operation of the front device of the hydraulic excavator including the first embodiment of the abnormality detection device for a construction machine according to the present invention.

FIG. 3 is a hydraulic circuit diagram showing a main part configuration relating to a boom hydraulic cylinder in the hydraulic drive system of the hydraulic excavator provided with the first embodiment of the abnormality detection device for a construction machine according to the present invention.

FIG. 4 is a flowchart showing the control contents of the abnormality / motion information processing unit that constitutes the first embodiment of the construction machine abnormality detection device of the present invention.

FIG. 5 is a diagram showing a criterion for determining a boom angular velocity V in the abnormality / motion information processing unit that constitutes the first embodiment of the abnormality detecting device for a construction machine according to the present invention.

FIG. 6 is a hydraulic circuit diagram showing a main configuration of a boom hydraulic cylinder in a hydraulic drive system for a hydraulic excavator including a second embodiment of the abnormality detection apparatus for a construction machine according to the present invention.

FIG. 7 is a flowchart showing the control contents of an abnormality / motion information processing unit which constitutes the second embodiment of the abnormality detection device for the construction machine of the present invention.

FIG. 8 is a hydraulic circuit diagram showing a main configuration of a hydraulic cylinder for a boom in a hydraulic drive system for a hydraulic excavator including a third embodiment of the abnormality detecting apparatus for a construction machine according to the present invention.

FIG. 9 is a flowchart showing the control contents of an abnormality / motion information processing unit constituting the third embodiment of the construction machine abnormality detection device of the present invention.

[Explanation of symbols]

1 Hydraulic Excavator (Construction Machinery) 6 Front Device 9 Lower Boom (Driven Member) 10 Upper Boom (Driven Member) 12 Arm (Driven Member) 15 Hydraulic Cylinder for Boom (Hydraulic Actuator) 16 Hydraulic Cylinder for Offset (Hydraulic Actuator) 17 Arm Hydraulic Cylinder (Hydraulic Actuator) 19 Boom Angle Sensor (Motion Detection Means; Angle Sensor) 20 Offset Angle Sensor (Motion Detection Means; Angle Sensor) 21 Arm Angle Sensor (Motion Detection Means; Angle Sensor) 22 Engine (Motor) 23 Hydraulic pump 25 Boom control valve 27 Operating lever device (operating means) 27b Potentiometer (operating amount detecting means) 31 Electromagnetic valve 32 Electromagnetic valve 37 Switching valve 41 Abnormal / motion information processing unit (switching detecting means;
First determination means; drive determination means) 41 'Abnormal / motion information processing unit (switch detection means;
First determination means; drive determination means) 41 ″ abnormality / motion information processing unit (switch detection means;
Second determination unit; drive determination unit) 42 angular velocity calculation unit (state amount calculation unit) 44 abnormality / motion information storage unit (abnormality information storage unit) 45 generator (rotation detection unit) 46 alarm buzzer (alarm unit) 50 engine stop Control unit (motor stop control means) 60 Gate lock lever device (gate lock device) 60b Switch (gate lock detection means) V Angular velocity (state quantity)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takeshi Yamaguchi             1-2, Sasagaoka, Mizuguchi Town, Koga District, Shiga Prefecture             Hitachi Construction Machinery Tierra Shiga Factory (72) Inventor Kazuo Fujishima             Hitachi Construction Machinery Co., Ltd.             Ceremony Company Tsuchiura Factory (72) Inventor Hiroshi Ogura             Hitachi Construction Machinery Co., Ltd.             Ceremony Company Tsuchiura Factory (72) Inventor Junji Tsumura             Hitachi Construction Machinery Co., Ltd.             Ceremony Company Tsuchiura Factory F-term (reference) 2D003 AA01 AB03 AB04 AC06 BA07                       CA02 DA04 DB04 DB05 DC02                 3H082 AA03 AA12 BB17 CC02 DA09                       DA23 DA39 DA41 DA42 DB26                       DB28 DB34 DE05 EE02                 3H089 BB12 BB28 CC01 DA02 DA08                       DA13 DB03 DB46 DB49 EE17                       EE22 FF04 FF05 FF10 FF25                       GG02 JJ02

Claims (10)

[Claims] 1. A prime mover, a hydraulic pump driven by the prime mover, an articulated front device, a hydraulic actuator for driving a driven member of the front device, and an operation for manually operating the hydraulic actuator. Means, a hydraulic pilot type control valve for controlling the flow of pressure oil from the hydraulic pump to the hydraulic actuator, an operation amount detecting means for detecting an operation amount of the operating means, and an operation amount detecting means for detecting the operation amount. Construction provided on a construction machine equipped with a solenoid valve for controlling pilot pressure to the control valve according to an operation amount, and a switching valve capable of connecting / disconnecting a pilot line from a pilot hydraulic source to the solenoid valve In a machine abnormality detection device, the hydraulic actuator or the driven member driven by the hydraulic actuator. Detection means for detecting the operation state of the switching valve, switching detection means for detecting the switching state of the switching valve, abnormality determination based on the detection results of the operation amount detection means, the operation detection means, and the switching detection means. An abnormality detection device for a construction machine, comprising: a first determination means. 2. The abnormality detecting device for a construction machine according to claim 1, wherein the first determining means detects that the operating means is not operated by the operation amount detecting means, and the operation detecting means operates. It is detected that the hydraulic actuator or the driven member corresponding to this is operating,
Further, the abnormality detecting device for a construction machine, wherein when the switching detecting unit detects that the switching valve is switched to the shut-off position, it is determined to be abnormal. 3. A prime mover, a hydraulic pump driven by the prime mover, an articulated front device, a hydraulic actuator for driving a driven member of the front device, and a pressure from the hydraulic pump to the hydraulic actuator. A hydraulic pilot type control valve for controlling the flow of oil, a solenoid valve for controlling the pilot pressure to this control valve, and a switching valve capable of connecting and disconnecting a pilot line from the pilot hydraulic power source to the solenoid valve, An abnormality detection device for a construction machine provided in a construction machine, comprising: a gate lock device that brings the switching valve into a closed position and the unlock position into an unlocked position to bring the switching valve into a communication position; Gate lock detecting means for detecting an operating state of the gate lock device, the hydraulic actuator or the hydraulic actuator. And a second determination unit for determining an abnormality based on the detection results of the gate lock detection unit and the operation detection unit, the operation detection unit detecting an operation state of the driven member driven by the user. Abnormality detection device for construction machinery. 4. The abnormality detecting device for a construction machine according to claim 3, wherein the second determining means detects that the gate lock detecting means operates the gate lock device to a lock position, and An abnormality detection device for a construction machine, which is determined to be abnormal when the operation detecting means detects that the hydraulic actuator or the driven member is operating. 5. The construction machine abnormality detection device according to claim 1, further comprising a prime mover stop control means for stopping the prime mover when the first or second determination means determines that there is an abnormality. Anomaly detection equipment for construction machinery. 6. The construction machine abnormality detection device according to claim 1, further comprising an alarm means for issuing an alarm when the first or second determination means determines an abnormality. Abnormality detection device for construction machinery. 7. The abnormality detecting device for a construction machine according to claim 1 or 3, further comprising an abnormality information storage unit that stores abnormality information when the first or second determination unit determines that the abnormality is present. Anomaly detection equipment for construction machinery. 8. The abnormality detecting device for a construction machine according to any one of claims 1 to 7, wherein a state quantity relating to an operation speed of the hydraulic actuator or the driven member is calculated from a detection result of the operation detecting means. State quantity calculation means for
Based on the state quantity of the hydraulic actuator or the driven member calculated by the state quantity calculation means, drive determination means for determining whether or not the hydraulic actuator is driven using a predetermined threshold value related to the state quantity. Prepare,
The drive determination means determines the absolute value of the threshold value of the state amount in the gravity acting direction of the driven member from the absolute value of the threshold value of the state amount in the direction opposite to the gravity acting direction of the driven member. An abnormality detection device for construction machinery, which is also characterized by being made larger. 9. The abnormality detecting apparatus for a construction machine according to claim 1, further comprising rotation detecting means for detecting the presence or absence of rotation of the prime mover, and the first or second determining means. An abnormality detection device for a construction machine, wherein abnormality determination is not performed when the rotation detection means detects a stopped state of the prime mover. 10. The construction machine abnormality detecting device according to claim 1, wherein the operation detecting means comprises:
An abnormality detection device for a construction machine, which is an angle sensor provided on the driven member driven by the hydraulic actuator.