JPH0789434A - Traveling restricting device for hydraulic shovel - Google Patents

Abstract

PURPOSE:To previously prevent the fall-down in the traveling on an ascent by sending a traveling stop signal to a return means from a controller when the calculation result exceeds a prescribed value, and by suspending the drive of a traveling motor on the basis of the traveling stop signal. CONSTITUTION:A controller 30 outputs a selection signal to the first and the second electromagnetic selector valves 28 and 29, and the pressurized oil discharged from a pilot pump 15 is returned into a tank 16. The pilot pressurized oil supplied into the pilot chambers of the first and the second direction selector valves 17 and 22 are cut off by the first and the second electromagnetic selector valves 28 and 29, and the first and the second direction selector valves 17 and 22 are automatically selected to a neutral position. Accordingly, even if an operator operates the pilot valve 18 for leftward traveling and the pilot valve 23 for rightward traveling, each revolution of the left and right traveling motors 2A and 2B is brought into stop, and a lower part traveling body 1 stops, and the fall-down of the car body can be prevented beforehand.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic excavator, and more particularly to a travel restricting device for a small turning hydraulic excavator.

[0002]

2. Description of the Related Art A hydraulic excavator comprises a lower traveling body which is driven by a traveling motor, an upper revolving body which is rotatably provided on the lower traveling body, and which is connected to the upper revolving body and includes a boom, an arm and a bucket. And a front, which is configured by, and drives the front using various cylinders to perform a required work such as digging a groove.
Also, drive the crawler track with a traveling motor to drive the undercarriage, especially when traveling on a narrow road, with the boom raised and the arm and bucket pulled forward so that the front does not get in the way. Let it run.

[0003]

By the way, in recent years, work in a narrow place such as an urban area has become extremely large, and in response to such a demand, a small turning hydraulic excavator having a small turning radius has been popularized. is doing. In such a small turning type hydraulic excavator, the turning radius is reduced by bringing the devices close to the turning center as much as possible, and the front also turns as close as possible to the turning center in a narrow place. For this reason,
The center of gravity of the vehicle body became high and became unstable, and especially when traveling with the boom raised and the arm and bucket pulled toward you when climbing uphill, there was a risk of the vehicle body falling over.

The present invention has been made in view of the circumstances of the prior art as described above, and an object thereof is to provide a hydraulic excavator capable of preventing a fall during traveling on an ascending slope.

[0005]

The above-described object of the present invention is to provide a lower traveling body, a traveling motor for driving the lower traveling body, a directional switching valve for driving and controlling the traveling motor, and a directional switching valve. A traveling pilot valve to be operated, an upper revolving structure rotatably provided on the lower traveling structure, a boom rotatably connected to the upper revolving structure, and a rotatably connected end of the boom. In a hydraulic excavator including an arm and a bucket rotatably connected to the tip of the arm, a tilt angle sensor that detects a tilt of the vehicle body in the front-rear direction, and a boom angle sensor that detects the angle of the boom. A controller for integrating the respective input signals of the tilt angle sensor and the boom angle sensor and comparing the integrated result with a predetermined value; and a return means for returning the directional switching valve to the neutral position, Calculation result is sent to the travel stop signal to said return means from said controller when exceeds a predetermined value, it is achieved by stopping the driving of the traveling motor on the basis of the travel stop signal.

Further, the above-mentioned object of the present invention is to provide a lower traveling body, a traveling motor for driving the lower traveling body, a directional switching valve for driving and controlling the traveling motor, and a traveling vehicle for operating the directional switching valve. A pilot valve, an upper revolving structure rotatably provided on the lower traveling structure, a boom rotatably connected to the upper revolving structure, and an arm rotatably connected to a tip of the boom. In a hydraulic excavator including a bucket rotatably connected to the tip of this arm, an inclination angle sensor for detecting the inclination of the vehicle body in the front-rear direction,
A boom angle sensor for detecting the angle of the boom, and a controller for accumulating the respective input signals of the tilt angle sensor and the boom angle sensor and comparing the integration result with a predetermined value are provided. This is accomplished by sending an alarm signal from the controller to the alarm means when exceeded.

[0007]

[Operation] When climbing a slope, the controller integrates the respective input signals of the tilt angle sensor for detecting the tilt of the vehicle body in the front-rear direction and the boom angle sensor for detecting the boom angle,
When this integrated value exceeds a preset safety value, a predetermined signal is sent to the returning means or the alarm means. Here, when the travel stop signal is sent from the controller to the return means, the direction switching valve automatically returns to the neutral position, so the travel motor stops rotating even though the travel pilot valve is operated. , Undercarriage will automatically stop before falling. Further, when an alarm signal is sent from the controller to the alarm means, when the operator operates the operation lever in the direction of lowering the boom, the center of gravity of the vehicle body is lowered, so that the vehicle can climb uphill without falling.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. First, the schematic configuration of the hydraulic excavator will be described with reference to the side view of the hydraulic excavator shown in FIG. In the figure, 1
Is a lower traveling body, 2 is a pair of traveling motors for traveling the lower traveling body 1 (hereinafter, the left traveling motor is denoted by reference numeral 2A, the right traveling motor is denoted by reference numeral 2B), and 3 is an upper portion of the lower traveling body 1. The upper revolving structure is arranged, and the lower traveling structure 1 and the upper revolving structure 3 form a vehicle body of the hydraulic excavator. 4 is a boom rotatably connected to the upper swing body 3,
5 is an arm rotatably connected to the tip of the boom 4, 6
Is a bucket rotatably connected to the tip of the arm 5,
Is a boom cylinder that drives the boom 4, 8 is an arm cylinder that drives the arm 5, and 9 is a bucket cylinder that drives the bucket 6. The boom 4, the arm 5, and the bucket 6 form the front. FIG. 5 is a configuration diagram schematically showing the upper revolving structure 3 and the front. In the figure, 10 is a boom angle sensor that detects the angle of the boom 4, and 11 is a tilt angle sensor that detects the tilt of the vehicle body in the front-rear direction. Is. The tilt angle sensor 11 is attached to an arbitrary position of the upper swing body 3 as shown in FIGS. 3 and 4,
It may be attached to the undercarriage 1.

FIG. 1 is a hydraulic circuit diagram of a travel restricting device according to an embodiment of the present invention provided in the hydraulic excavator of FIG. 4, and a description of actuators other than the travel motor 2 described above will be omitted. In these figures, 12 is a prime mover, 13 and 14 are main pumps, 15 is a pilot pump, and 16 is a tank. Reference numeral 17 denotes a first directional control valve. This directional control valve 17 has pilot chambers on both left and right sides and controls the flow of pressure oil supplied from the main pump 13 to the left travel motor 2A. 18 is a traveling motor 2
A left traveling pilot valve for operating A, 19 is an operation lever thereof, and a chamber on the left side of the left traveling pilot valve 18 and a left pilot chamber of the first direction switching valve 17 are connected via a pilot line 20. The chamber on the right side of the left traveling pilot valve 18 and the pilot chamber on the right side of the first direction switching valve 18 are connected via a pilot line 21. Reference numeral 22 denotes a second directional control valve, and the second directional control valve 22 also has pilot chambers on both left and right sides, and controls the flow of pressure oil supplied from the main pump 14 to the right travel motor 2B. . Reference numeral 23 is a right traveling pilot valve for operating the traveling motor 2B, and 24 is an operating lever thereof. The chamber on the left side of the right traveling pilot valve 23 and the pilot chamber on the left side of the second direction switching valve 22 are pilot pipes. The chamber on the right side of the right traveling pilot valve 23 and the pilot chamber on the right side of the second directional control valve 22 are connected to each other via a passage 25.
The left and right chambers of the left traveling pilot valve 18 and the right traveling pilot valve 23 are connected to the pilot pump 15 via a pipe 27.

Numeral 28 is a first solenoid operated directional control valve.
The electromagnetic switching valve 28 has a port connected to the pilot lines 20 and 21 and a port connected to the tank 16. Reference numeral 29 denotes a second electromagnetic switching valve, and the second electromagnetic switching valve 29 is used for both the pilot pipe lines 25 and 26.
And a port connected to the tank 16, and these first and second electromagnetic switching valves 2
The return means is constituted by 8, 29. Reference numeral 30 denotes a controller. The controller 30 inputs signals from the boom angle sensor 10 and the tilt angle sensor 11, and performs arithmetic processing to be described later on these input signals,
A switching signal is output to the first electromagnetic switching valve 28 and the second electromagnetic switching valve 29. That is, as shown in FIG. 2, the controller 30 controls the signal corresponding to the angle α sensed by the boom angle sensor 10 and the angle θ sensed by the tilt angle sensor 11.
And a calculation unit 32 for calculating a product of both signals input to the input unit 31 to obtain an integrated value S = α × θ, and the integrated value S is set in advance. A comparing unit 33 which determines whether or not the safety value Sa is exceeded.
The output unit 34 that outputs a switching signal to the first electromagnetic switching valve 28 and the second electromagnetic switching valve 29 based on the determination result of the comparison unit 33 is built in.

The operation of this embodiment will now be described. When there is no danger of the vehicle body falling over, the first electromagnetic switching valve 28 is at the right position 28b and the second electromagnetic switching valve 29 is at the right position. 29b. In this state, the operation lever 19 is
The pressure oil discharged from the pilot pump 15 passes through the conduit 27, the chamber on the left side of the left traveling pilot valve 18, the first electromagnetic switching valve 28, and the pilot conduit 20 in the first direction. It is supplied to the pilot chamber on the left side of the switching valve 17. As a result, the first directional control valve 17 starts to operate, and the first directional control valve 17 moves to the left position 1 from the neutral position.
When switched to 7a, the pressure oil of the main pump 13 is supplied to the left travel motor 2A via the first direction switching valve 17, and the left travel motor 2A rotates in one direction. On the contrary, when the operation lever 19 is tilted to the right side in FIG. 1, the pressure oil discharged from the pilot pump 15 is discharged from the conduit 2
7, the chamber on the right side of the left traveling pilot valve 18, the first electromagnetic switching valve 28, and the pilot conduit 21 are supplied to the pilot chamber on the right side of the first direction switching valve 17. As a result, the first direction switching valve 17 starts to operate, and when the first direction switching valve 17 is switched from the neutral position to the position 17b on the right side, the pressure oil of the main pump 13 is changed to the first direction switching valve 17. Is supplied to the left traveling motor 2A, and the left traveling motor 2A rotates in the other direction.

Similarly, when the operating lever 24 is tilted to the left side in FIG. 1, the pressure oil discharged from the pilot pump 15 is supplied to the pipe line 27, the chamber on the left side of the right traveling pilot valve 23, the second chamber.
It is supplied to the pilot chamber on the left side of the second directional control valve 22 via the electromagnetic switching valve 29 and the pilot conduit 25. As a result, the second directional control valve 22 starts to operate, and when the second directional control valve 22 is switched from the neutral position to the position 22a on the left side, the pressure oil of the main pump 14 is changed to the second directional control valve 22. Is supplied to the right-side traveling motor 2B, and the right-side traveling motor 2B rotates in one direction. On the contrary, when the operation lever 24 is tilted to the right side in FIG. 1, the pressure oil discharged from the pilot pump 15 is supplied to the pipe line 27, the chamber on the right side of the right traveling pilot valve 23, and the second electromagnetic switching valve. Two
9 and is supplied to the pilot chamber on the right side of the second directional control valve 22 via the pilot pipe line 26. As a result, the second directional control valve 22 starts operating and the second directional control valve 22
Is switched from the neutral position to the right position 22b,
The pressure oil of the main pump 14 is supplied to the right traveling motor 2B via the second direction switching valve 22, and the right traveling motor 2B is supplied.
B rotates in the other direction. Therefore, both operating levers 1
The left and right traveling motors 2A and 2B are rotated in the forward direction or the reverse direction by operating the 9 and 24 individually or in combination, and the lower traveling body 1 is rotated in accordance with the rotation direction of these traveling motors 2A and 2B.
Moves forward or backwards.

As described above, while the lower traveling vehicle 1 is traveling, the controller 30 calculates the product of the angle α sensed by the boom angle sensor 10 and the angle θ sensed by the tilt angle sensor 11, and the integrated value S = α. The magnitude relationship between × θ and the safety value Sa is successively compared. When the undercarriage 1 is traveling on a flat road, no matter what the posture of the front, the angle θ sensed by the inclination angle sensor 11 is 0 or a value close thereto, so the integrated value S = α. Since xθ does not exceed the safe value Sa, the lower traveling body 1 can travel without falling.

On the other hand, while the lower traveling body 1 is traveling uphill on a slope having a large inclination angle θ, in particular, as shown in FIG. 4, with the boom 4 raised and the arm 5 and the bucket 6 pulled toward you, the angle θ is increased.
When the vehicle goes up a hill, the angle α and the angle θ both become large values, so the integrated value S = α × θ exceeds the safety value Sa, and there is a risk of the vehicle body falling over. In this case, the controller 30
Outputs a switching signal to the first electromagnetic switching valve 28 and the second electromagnetic switching valve 29, and as a result, the first electromagnetic switching valve 28 and the second electromagnetic switching valve 29 are both on the left side positions 28a, 29a. The pressure oil discharged from the pilot pump 15 is returned to the tank 16. As a result, the pilot pressure oil that has been supplied to the pilot chambers of the first direction switching valve 17 and the second direction switching valve 22 is shut off by the first electromagnetic switching valve 28 and the second electromagnetic switching valve 29. The first directional control valve 17 and the second directional control valve 22 are automatically switched to the neutral position. Therefore, even though the operator is operating the left traveling pilot valve 18 and the right traveling pilot valve 23, the left and right traveling motors 2A and 2B stop rotating and the lower traveling body 1 stops, and the vehicle body falls over. Can be prevented in advance. When the undercarriage 1 is stopped in this way, when the operator drives the boom cylinder 7 with an operation lever (not shown) to lower the boom 4 from the position shown in FIG. 4, that is, when the value of the angle α is reduced, Since the above-mentioned integrated value S becomes smaller than the safety value Sa, the first and second electromagnetic switching valves 28, 29 are again moved to the right position 28 by the switching signal from the controller 30.
It is possible to continue climbing as it is by switching to b and 29b.

As described above, in the above-described embodiment, the controller 3 is operated when there is a risk of the vehicle body falling over while traveling uphill.
Since the first directional switching valve 17 and the second directional switching valve 22 are switched to the neutral position by the switching signal from 0,
Although the operator operates the left traveling pilot valve 18 and the right traveling pilot valve 23, the left and right traveling motors 2A and 2B stop rotating and the lower traveling body 1 is automatically moved before the vehicle body falls. Can be stopped.

FIG. 3 is a circuit diagram showing an essential part of a travel restricting device according to another embodiment of the present invention. This embodiment is different from the above-mentioned embodiment in that the first and second electromagnetic switching valves 2
Instead of providing the resetting means composed of 8 and 29, an alarm device 35 including an alarm lamp, an alarm buzzer, etc. is provided, and the alarm device 3 is generated by an output signal from the controller 30.
5 is operated, and other circuit configurations are basically the same.

That is, the controller 30 inputs a signal corresponding to the angle α sensed by the boom angle sensor 10 and a signal corresponding to the angle θ sensed by the tilt angle sensor 11,
If the integrated value S = α × θ of these two signals and the safety value Sa are compared in magnitude, and if the integrated value S exceeds the safety value Sa,
An alarm signal is sent to the alarm device 35 to operate it. Therefore, the operator can detect that the vehicle body is in danger of falling while traveling uphill by activating the alarm device 35 such as turning on a lamp or an alarm sound. In that case, lower the boom 4 to climb uphill as described above. All you have to do is continue running.

[0018]

As described above, according to the travel restriction device for a hydraulic excavator of the present invention, the tilt angle sensor for detecting the tilt of the vehicle body in the front-rear direction when there is a risk of the vehicle body falling over. Based on the input signals of the boom angle sensor that detects the boom angle, the travel motor rotation is automatically stopped, and an alarm is issued to notify the operator of the dangerous state. It can be prevented.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram of a travel restriction device according to an embodiment of the present invention.

FIG. 2 is a block diagram of a controller included in the travel restriction device of FIG.

FIG. 3 is a circuit diagram showing a main part of a travel restriction device according to another embodiment of the present invention.

FIG. 4 is a side view of a hydraulic excavator targeted by the present invention.

5 is a configuration diagram schematically showing an upper revolving structure and a front provided in the hydraulic excavator of FIG.

[Explanation of symbols]

 1 Lower Traveling Body 2, 2A, 2B Traveling Motor 3 Upper Revolving Body 4 Boom 5 Arm 6 Bucket 7 Boom Cylinder 10 Boom Angle Sensor 11 Inclination Angle Sensor 13, 14 Main Pump 16 Tank 17 First Directional Change Valve 18 For Left Traveling Pilot valve 19,24 Operating lever 20,21,25,26 Pilot line 22 Second direction switching valve 23 Right travel pilot valve 28 First electromagnetic switching valve 29 Second electromagnetic switching valve 30 Controller 31 Input section 32 Calculation unit 33 Comparison unit 34 Output unit 35 Alarm device

Claims (3)

[Claims] 1. A lower traveling body, a traveling motor for driving the lower traveling body, a direction switching valve for driving and controlling the traveling motor, a traveling pilot valve for operating the direction switching valve, and the lower traveling body. An upper revolving structure that is rotatably provided in the upper revolving structure, and a boom that is rotatably connected to the upper revolving structure,
In a hydraulic excavator including an arm rotatably connected to the tip of the boom and a bucket rotatably connected to the end of the arm, an inclination angle sensor that detects an inclination of the vehicle body in the front-rear direction, A boom angle sensor that detects the boom angle, a controller that integrates the respective input signals of the tilt angle sensor and the boom angle sensor, and compares the integrated result with a predetermined value, and the directional switching valve is returned to the neutral position. A resetting means, and when the integrated result exceeds a predetermined value, a traveling stop signal is sent from the controller to the restoring means, and the drive of the traveling motor is stopped based on the traveling stop signal. A travel restriction device for hydraulic excavators. 2. The return means according to claim 1, wherein the returning means is provided in a pilot pipe line connecting the directional control valve and the traveling pilot valve, and the pilot pipe line is selectively connected to a tank. A travel restriction device for a hydraulic excavator, which is composed of an electromagnetic switching valve. 3. A lower traveling body, a traveling motor for driving the lower traveling body, a direction switching valve for driving and controlling the traveling motor, a traveling pilot valve for operating the direction switching valve, and the lower traveling body. An upper revolving structure that is rotatably provided in the upper revolving structure, and a boom that is rotatably connected to the upper revolving structure,
In a hydraulic excavator including an arm rotatably connected to the tip of the boom and a bucket rotatably connected to the end of the arm, an inclination angle sensor that detects an inclination of the vehicle body in the front-rear direction, A boom angle sensor for detecting the angle of the boom, and a controller for accumulating the respective input signals of the tilt angle sensor and the boom angle sensor and comparing the integration result with a predetermined value are provided. A traveling restriction device for a hydraulic excavator, wherein an alarm signal is sent from the controller to an alarm means when it exceeds.