JPH08269998A - Area limit control device for construction machine - Google Patents

Abstract

PURPOSE: To quickly cancel the area limit control in response to the necessity in the work in an area limit control device for construction machine. CONSTITUTION: A floating estimation computing unit obtains an intermediate floating predicted value due to the inclination on the basis of the angle θa of inclination of a car body, which is detected by an inclination sensor 14, and obtains the intermediate floating predicted value due to the turning on the basis of the angle θt of turning of an upper turning body, which is detected by a turning angle sensor 15. The intermediate floating predicted value due on the front position is obtained on the basis of the bucket tip data, which is computed by a front position computing unit. Each obtained intermediate floating predicted value is multiplied by each other so as to obtain the final floating predicted value of a car body. In the case where the final floating predicted value is larger than the criterion, a floating predicted value judging unit judges that there is a possibility of floating of a car body, and outputs the limit OFF flag, and a command signal selecting unit cancels the area limit control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a region limiting control device for construction machines such as hydraulic excavators, and more particularly to a region limiting control device for construction machines suitable for releasing the region limiting control.

[0002]

2. Description of the Related Art A hydraulic excavator is a typical example of construction machines. The hydraulic excavator is provided with a vehicle body having a lower work structure, an upper revolving structure rotatably attached to the lower travel structure, a boom, an arm, and a bucket, which are vertically rotatable, and front work devices including front work members. The base of the boom of the front working device is supported by the front part of the upper swing body. In such a hydraulic excavator, a front work member such as a boom is operated by respective manual operation levers. However, since these front work members are connected by joints to perform a rotary motion, a predetermined movement is required. It is very difficult to operate and operate those front working members within the area. Therefore, an area limitation control device for facilitating such work with area limitation is disclosed in Japanese Patent Laid-Open No. 4-136324.
No., published in Japanese Unexamined Patent Publication No.

In this prior art, the front working device position calculating means calculates the position of the front working device based on a signal from the front working device attitude detecting means, and the lever gain calculating means obtains the front working device position calculating means. The distance between the position of the work device and the teaching area from the inaccessible area teaching means is obtained, and a signal determined from the operating lever is multiplied by a function determined according to the distance, and the actuator control means outputs the lever gain calculation means. Signal to control the movement of the actuator. With this configuration, even if an operator mistakenly attempts to move the bucket blade edge to the inaccessible area, the bucket blade edge automatically stops smoothly on the boundary line, and in the middle of that, the operator operates the speed of the front working device. It is possible to return the bucket blade edge by judging that the area is approaching the inaccessible area from the decrease of

[0004]

However, the above-mentioned prior art has the following problems. The area limitation control device was originally developed for the purpose of reducing the operational burden on a worker and improving workability. That is, by controlling the front work device so as not to enter the inaccessible area, that is, the restricted area even if the worker unknowingly works, the work is performed without being aware of the front work device entering the restricted area. It allows you to do things. For this reason, when the worker concludes that performing the area restriction control may impose an operational burden or impair the workability, he or she can cancel the area restriction function at will. .

However, when it is desired to quickly release the area limiting function, the operator tries to move the front working device to the restricted area by operating the manual operation lever immediately before the operation of releasing the area limiting function. I have something to do. However, if the area restriction function is working at this time,
Unlike the operator's will, since the speed of the front working device decreases from the time when the distance from the bucket blade edge to the boundary line of the restricted area becomes equal to or less than a predetermined value, the front work device automatically stops on the boundary line of the restricted area. It takes time and effort to release the area restriction function.

An object of the present invention is to provide an area limiting control device for a construction machine, which can quickly release the area limiting control according to work needs.

[0007]

The present invention adopts the following constitution in order to achieve the above object. That is, a vehicle body having an undercarriage, an upper revolving structure that is rotatably attached to the lower traveling structure, and an articulated front working device that is attached to the upper revolving structure and includes a plurality of front working members. (A) detecting the state quantity of the vehicle body, in a region limitation control device for a construction machine, wherein the region limitation control device for a construction machine sets a movable region of the front work device and performs a region limitation control so that the front work device moves only within the set region. And (b) a determination means for determining whether or not the vehicle body may float based on the state quantity of the vehicle body detected by the detection means; and (c) a vehicle body floated by the determination means. A control means for canceling the area limitation control when it is determined that there is a possibility.

In the area limitation control device for the construction machine described above, preferably, the control means releases the area limitation control and then the area is determined when the determination means determines that the vehicle body is not likely to float. Return to limit control.

Further, preferably, the detecting means has a means for detecting the inclination of the vehicle body, and the judging means determines whether or not the vehicle body may float based on the detected value of the inclination of the vehicle body. It is a means to judge.

Further, preferably, the detecting means has a means for detecting the inclination of the vehicle body and a means for detecting a state quantity relating to the position and orientation of the front working device, and the judging means is the vehicle body. Means for calculating the position and orientation of the front working device based on the state quantity of the vehicle, and the possibility that the vehicle body may rise based on the detected value of the inclination of the vehicle body and the calculated value of the position and posture of the front working device. And a means for determining whether there is any.

Further, preferably, the detecting means has a means for detecting a tilt of the vehicle body and a means for detecting a turning position of the upper swing body, and the judging means detects a tilt of the vehicle body. It is means for judging whether or not there is a possibility that the vehicle body will float up based on the value and the detected value of the turning position of the upper-part turning body.

Further, preferably, the detecting means detects a tilt of the vehicle body, a means for detecting a state quantity relating to a position and a posture of the front working device, and a turning position of the upper swing body. Means for calculating the position and orientation of the front working device based on the state quantity of the vehicle body, the detected value of the inclination of the vehicle body, the position and orientation of the front working device. And means for determining whether or not the vehicle body may float based on the calculated value and the detected value of the turning position of the upper swing body.

Further, preferably, the detecting means detects a tilt of the vehicle body, a means for detecting a state quantity relating to a position and a posture of the front working device, and a turning position of the upper swing body. Means for calculating the position and orientation of the front working device based on the state quantity of the vehicle body, and dividing the detected value of the inclination of the vehicle body by the limit inclination angle of the vehicle body. The first intermediate vehicle body levitation predicted value is obtained by dividing the calculated value of the position and orientation of the front working device by the limit reach length of the front working device to obtain the second intermediate vehicle body levitation predicted value. The third intermediate vehicle body levitation predicted value is obtained by dividing the detected value of the slewing position of the upper slewing body by the limit slewing angle of the upper slewing body to obtain the first intermediate vehicle body levitation predicted value. Second intermediate car body Means for calculating a final predicted vehicle body floating value by multiplying the upper predicted value and a third intermediate predicted vehicle body floating value; and the vehicle body when the final predicted vehicle body floating value exceeds a determination value. And a means for determining that there is a possibility of emergence.

In this case, preferably, the judging means is
It further comprises a judgment value changing means for changing the judgment value.

In this case, for example, the judgment value changing means has a manual setting means capable of arbitrarily setting the judgment value and a means for changing the judgment value according to the setting value by the manual setting means.

Further, the judgment value changing means is responsive to the pressure detection means for detecting the pressure in at least one of the plurality of cylinders driving the plurality of front working members, and the detection value by the pressure detection means. And a means for changing the determination value.

[0017]

In the area limitation control device for a construction machine of the present invention configured as described above, the computing means judges whether or not the vehicle body may float based on the state quantity of the vehicle body,
When it is determined that the vehicle body may float, the control means releases the area limitation control, so that when the area limitation control is working, the vehicle body may be in an unnatural posture on a slope, for example, and may float up. When this happens, the area limitation control is automatically released. Therefore, the area limitation control can be quickly released according to the work need.

Further, after canceling the area limiting control, when the determining means determines that the vehicle body is not likely to float, the control means returns to the area limiting control so that the operator can instruct the area limiting control again. There is no need to do this, and the burden on the operator is reduced.

Further, by providing a manual setting means capable of arbitrarily setting the judgment value as the judgment value changing means, the possibility of floating of the vehicle body increases when working in an unstable place such as a wetland. Decrease the value to release the area restriction control earlier, and increase the judgment value to delay the area restriction control release when working in a place where you do not want to release the area restriction control, such as in a narrow space. The worker can change the judgment value according to the situation.

Further, as the judgment value changing means, a pressure detecting means for detecting the pressure in at least one of the plurality of cylinders for driving the plurality of front working members is provided, and the front working device is determined from the value detected by the pressure detecting means. By predicting the load on the vehicle and changing the judgment value, when it is predicted that heavy excavation is likely due to the pressure in the cylinder due to the pressure inside the cylinder, the judgment value will be reduced and the region restriction control will be released earlier. As described above, the determination value is automatically changed according to the work situation, so that the burden on the worker is reduced.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. First, a first embodiment in which the present invention is applied to a hydraulic excavator will be described with reference to FIGS. In FIG. 1, a hydraulic excavator to which the present invention is applied is a hydraulic pump 2
2, a boom cylinder 23a and an arm cylinder 23 driven by pressure oil discharged from the hydraulic pump 22.
b, a plurality of actuators including the bucket cylinder 23c, and a plurality of electromagnetic operation lever devices 24a, 24b, 24 provided corresponding to each of the actuators 23a to 23c and outputting electric signals as operation signals.
c, the hydraulic pump 22, and the plurality of actuators 23a to
23c, and electromagnetic type directional control valves 25a, 25b, 25c for controlling the operation of the actuators 23a-23c by operating signals of the operating lever devices 24a-24c.
And a relief valve 26 that opens when the pressure between the hydraulic pump 22 and the direction switching valves 25a to 25c becomes equal to or higher than a set value, and these constitute a hydraulic drive device.

As shown in FIG. 2, the hydraulic excavator includes a lower traveling body 10A, an upper revolving body 10B attached to the lower traveling body 10A so as to be rotatable, and an upper revolving body 1.
The vehicle body 10 has a multi-joint type front working device 10C that is attached to the front part of 0B and is driven by a boom cylinder 23a, an arm cylinder 23b, and a bucket cylinder 23c, and includes a boom 10a, an arm 10b, and a bucket 10c. .

The above-described hydraulic excavator is provided with the area limiting control device of this embodiment. This area restriction control device sets an arbitrary restricted area in advance by a worker, compares the position of the front working apparatus 10C with the set restricted area, and when the front working apparatus 10C attempts to enter the restricted area, A device that stops the front working device 10C or operates along the boundary of the restricted area, and operates the front working device 10C so as not to enter the restricted area.
The boom angle sensor 11, the arm angle sensor 12, the bucket angle sensor 13, the tilt sensor 14, the turning angle sensor 15, the area limitation control instruction switch 19, the limitation area setting switch 20, the determination value setting switch 21, and the controller. And 27.

The boom angle sensor 11, the arm angle sensor 12, and the bucket angle sensor 13 are used for the boom 10 respectively.
a, the arm 10b, and the bucket 10c are provided at the fulcrum of rotation, and the respective rotation angles (boom angle θ _BM , arm angle θ) are provided as state quantities related to the position and posture of the front working device 10C.
_AM , bucket angle θ _BK ) are detected. The tilt sensor 14 is provided on the upper swing body 10B and detects the tilt angle (absolute value) θ _a of the vehicle body 10. The swing angle sensor 15 is provided on the upper swing body 10B and detects the swing angle θ _t of the upper swing body 10B. Here, the boom angle sensor 11, the arm angle sensor 12, the bucket angle sensor 13, the tilt sensor 14,
The turning angle sensor 15 constitutes a detecting means for detecting the state quantity of the vehicle body 10.

The area restriction control instruction switch 19 is a switch for instructing area restriction control. The restriction area setting switch 20 is a switch for instructing the setting of the restriction area when the area restriction control instruction switch 19 instructs the area restriction control. For example, as shown in FIG. It is possible to set restriction regions in the height direction of the water, the depth direction for preventing collision with a buried object such as a water pipe, and the length (reach) direction for preventing collision with the front. Here, when the work is stopped, there is no possibility that the front working device 10C enters the restricted area, and therefore it is not necessary to set the restricted area. Further, since it is not possible to travel if there is a restricted area during traveling, it is not necessary to set the restricted area even when traveling. The judgment value setting switch 21 is used for the controller 2
7 is a manual setting means capable of arbitrarily setting a determination value H used when determining whether or not the vehicle body 10, which will be described later, may float. This judgment value setting switch 21
Indicates several kinds of judgment values H (for example, 0.4, 0.5, 0.6
Etc.) are prepared and can be selected by the operator according to the work situation.

The controller 27 includes the operation lever devices 24a to 24c, the boom angle sensor 11, the arm angle sensor 12, the bucket angle sensor 13, the tilt sensor 14,
Turning angle sensor 15, area limitation control instruction switch 19,
Signals from the restricted area setting switch 20 and the judgment value setting switch 21 are input and predetermined arithmetic processing is performed.
As shown in, the operation signal-command signal conversion unit 27a, the front position calculation unit 27b, the limit control calculation unit 27c, the flying prediction calculation unit 27d, the determination value setting unit 27e, the flying prediction determination unit 27f, and the command signal selection unit 27g. It has each function.

The operation signal-command signal conversion unit 27a is based on the relationship between the operation signal and the command signal, and the directional control valve 2 responds to the operation signals from the operation lever devices 24a to 24c.
The command signal to 5a-25c is generated.

The front position calculating section 27b has a distance L ₁ between the pivot fulcrum of the boom 10a and the pivot fulcrum of the arm 10b stored in advance, and a distance between the pivot fulcrum of the arm 10b and the pivot fulcrum of the bucket 10c. L ₂ , the distance L ₃ between the rotation fulcrum of the bucket 10c and the tip of the bucket 10c, the boom angle sensor 11, the arm angle sensor 1
2, the boom angle θ _BM , the arm angle θ _AM , the bucket angle θ _BK, and the tilt angle θ _a detected by the bucket angle sensor 13 and the tilt sensor 14, respectively.
The positions of 0b and the bucket 10c are calculated and output as front position information _If . Here, the front position information I _f
Includes the distance L _BK between the pivot fulcrum of the boom 10a and the tip of the bucket 10c as bucket tip data.

When the area restriction control instruction switch 19 instructs the area restriction control, the restriction control calculation unit 27c sets the restriction area in accordance with the setting instruction from the restriction area setting switch 21, and the front position calculation unit 27c. 27
The operation signals from the operation lever devices 24a to 24c are corrected based on the front position information _If from b, and the command signals to the directional control valves 25a to 25c are set so as not to enter the restricted area set by the front working device 10C. Calculate

When the area limitation control instruction switch 19 gives an instruction for area limitation control, the flying height calculation section 27d detects the inclination angle θ _a of the vehicle body 10 detected by the inclination sensor 14,
Turning angle theta _t of the upper frame 10b detected by the turning angle sensor 15, based on the front position information I _f calculated by the front position calculation unit 27b, calculates a flying predicted value k _d of the vehicle body 10. The details of this calculation will be described below.

That is, as shown in FIG. 5, when the vehicle body 10 is extremely inclined, depending on the position of the upper swing body 10B, the position of the front working device 10C, the state of the front working device 10C (during excavation, etc.), etc. The vehicle body 10 becomes easier to fly than in the normal state, that is, in the horizontal position. For example, when the vehicle body 10 is tilted in a state where the upper swing body 10B is at a position of 90 ° with respect to the lower traveling body 10A, the probability that the vehicle body will fly is higher than in the normal state. Also,
As shown in FIG. 6, when the tip of the front working device 10C is located farther than the upper swing body 10B (a), the center of gravity of the boom 10a, the arm 10b, and the bucket 10c are also far from each other, so that the front working device is far away. The probability of levitating is higher than in the case (b) in which the tip of 10C is located closer to the upper swing body 10B.

Therefore, in the present embodiment, the possibility of levitation due to the inclination angle of the vehicle body 10 is determined based on the inclination angle θ _a of the vehicle body 10 detected by the inclination sensor 14 as an intermediate levitation prediction value due to the inclination, and the upper revolving structure is determined. The possibility of levitation due to the turning angle of 10B is obtained as an intermediate floating prediction value due to turning based on the turning angle θ _t of the upper-part turning body 10B detected by the turning angle sensor 15, and the levitation depending on the position and attitude of the front working device 10C. Is calculated based on the front position information I _f calculated by the front position calculation unit 27b as an intermediate floating predicted value based on the front attitude, and the intermediate floating predicted value thus obtained is multiplied to obtain the value of the vehicle body 10. The final predicted flying height value is k _d . Here, the inclination angle of the vehicle body 10 (absolute value)
When θ _a is 30 °, the intermediate leaning prediction value due to the tilt at this time is taken as the limit lean angle of the vehicle body 10, and the turning angle θ _t of the upper swing body 10B is 90 °. When the intermediate levitation predicted value due to the turning at this time is set as 1.0 as the limit turning angle of 10B, and the distance L _BK between the turning fulcrum of the boom 10a and the tip of the bucket 10c is at the longest L, the front working device 10C. As the limit reach length of 1.
Set to 0. The limit tilt angle of the vehicle body 10 and the upper swing body 1
The limit turning angle of 0B and the limit reach length of the front working device 10C may not be the above values.

The judgment value setting unit 27e performs the setting calculation of the judgment value H according to an instruction from the judgment value setting switch 21.

The levitation prediction judging unit 27f compares the final levitation prediction value k _{d of} the vehicle body 10 obtained by the levitation prediction calculating unit 27d with the judgment value H set by the judgment value setting unit 27e, and the vehicle body 1
If the final predicted flying height k _{d of} 0 is larger than the judgment value H, it is judged that the vehicle body 10 may float and the limit is turned off.
The flag F _OFF is output.

The command signal selection unit 27g switches the switches 27ga and 27gb according to the area restriction control instruction signal from the area restriction control instruction switch 19 and the restriction OFF flag F _OFF from the levitation determination unit 27f, and the direction switching valve 25.
A command signal to be output to a to 25c is selected. That is,
When the area restriction control instruction switch 19 does not instruct the area restriction control, the switch 27ga is kept open and the switches 27gb are kept at the positions shown.
On the other hand, when the area limiting control instruction switch 19 instructs the area limiting control, the switch 27ga is switched from the open state to the closed state shown in the figure, and therefore the switch 27gb is switched from the position shown in the figure. Further, when the area limiting control instruction switch 19 instructs the area limiting control and the flying height determining unit 27f outputs the limitation OFF flag F _OFF , the switch 27ga is switched from the closed state to the open state, and the switches 27gb are respectively switched. Switch to the position shown.

The control function of the controller 27 will be further described with reference to the flow charts shown in FIGS. First, Fig. 7
In step 101, it is determined whether or not there is an instruction for area limitation control from the area limitation control instruction switch 19,
If it is determined that there is no area restriction control instruction, normal processing without area restriction control is performed in step 102, and if it is determined that there is area restriction control instruction, the vehicle body 10 is levitated in step 103. Do what you expect.

Details of the processing in step 103 are shown in FIG.
Shown in First, in step 131, the inclination sensor 14
The inclination angle θ _a of the vehicle body 10 detected in Step 1 is input to determine whether the vehicle body 10 is leaning. When it is determined that the vehicle body 10 is not leaning, the routine proceeds to step 139, where the vehicle body 1
When it is determined that 0 is inclined, in step 132, the input inclination angle θ _a is set to 30 ° which is the limit inclination angle.
In intermediate floating predicted value k _da due inclined by dividing
Ask for.

Next, at step 133, the turning angle θ _t of the upper-part turning body 10B detected by the turning angle sensor 15 is inputted, and then at step 134, the inputted turning angle θ _t is divided by 90 ° which is the limit turning angle. By doing this, the intermediate predicted flying value due to turning is obtained, and step 1
Multiplying the intermediate levitation predicted value k _da by the tilt obtained in 32, the intermediate levitation predicted value k _dt by the tilt / turn
Ask for.

[0039] Then, in step 135, enter the bucket tip data reception location information I _f calculated by the reception position calculating section 27b, then in step 136, the distance L _BK between the tip of the pivot point and the bucket 10c of the boom 10a Is divided by the longest value L, which is the limit reach length of the front working device 10C, to obtain an intermediate levitation predicted value due to the front posture. By multiplying _dt , the final predicted flying height k _d of the vehicle body 10 is obtained.

Next, at step 137, the vehicle body 10
The final floating predicted value k _d is determined whether the determination value is greater than H set by the determination value setting unit 27e, when the final floating predicted value k _d is determined to be greater than the judgment value H , Area restriction OFF flag F in step 138
After setting _OFF , the process proceeds to step 104 of FIG. 7, and when it is determined that the final predicted flying height k _d is not larger than the determination value H, the region restriction OFF is performed in step 139.
After clearing the flag F _OFF , the process proceeds to step 104 in FIG. 7.

[0041] Returning to FIG. 7, in step 104, to determine whether the area limiting OFF flag F _OFF is set, in step 105 when the area limiting OFF flag F _OFF is determined not to be set, the area When the limit control is performed and it is determined that the output region limit OFF flag F _OFF is set, in step 102, the region limit control is released and normal processing without the region limit control is performed.

In the above, the process of step 101 is performed by the switch 27gb of the command signal selection unit 27g, and the process of step 103 is performed by the flying height calculation unit 27d, the judgment value setting unit 27e, and the flying height judgment unit 27f. 1
The process of 04 is the switch 27ga of the command signal selection unit 27g.
The operation signal-command signal converter 27a performs the process of step 102, and the front position calculator 27b and the limit control calculator 27c perform the process of step 105. In step 103, steps 131 to
The processing of 136 is performed by the flying height calculation unit 27d, the processing of step 137 is performed by the determination value setting unit 27e and the flying height determination determination unit 27f, and the processing of steps 138 and 139 is performed by the flying height determination determination unit 27f.

Further, the processing of step 103 is based on the state quantity of the vehicle body 10 detected by the detecting means.
0 constitutes a judging means for judging whether there is a possibility that the vehicle body 10 may float, and the processing of steps 104 and 102 cancels the area limitation control when the judging means judges that the vehicle body 10 may float. The control means is configured to do so.

Next, the operation of this embodiment having the above configuration will be described. First, when the operator does not instruct the area restriction control instruction switch 19 to perform the area restriction control, the switch 27ga of the command signal selection unit 27g is kept in the open state shown in the figure, and the switch 27gb is kept in the position shown in the figure. As a result, command signals corresponding to the operation signals of the operation lever devices 24a to 24c, which are generated by the operation signal-command signal conversion unit 27a, are output to the direction switching valves 25a to 25c.

On the other hand, when the operator gives an instruction for the area limitation control by the area limitation control instruction switch 19, the operator subsequently sets the limitation area by the limitation area setting switch 21 and sets the judgment value according to the work situation. The judgment value H is changed by the switch 21. At this time, the limit control calculation unit 2
At 7c, a command signal is calculated based on the front position information _If from the front position calculation unit 27b so as not to enter the restricted area set by the front working apparatus 10C. In addition, in the levitation prediction calculation unit 27d, the inclination angle θ _{a of} the vehicle body 10,
The swing angle θ _t of the upper swing body 10b and the front position information I _f
The predicted levitation value k _d of the vehicle body 10 is calculated on the basis of the calculated levitation predicted value k _d.
By comparing _d with the determination value H, it is determined whether or not the vehicle body 10 may float.

At this time, when it is determined that the predicted floating value k _d of the vehicle body 10 is less than or equal to the determination value H, there is no possibility that the vehicle body 10 will float, so the switch 27ga of the command signal selection unit 27g is shown in the figure. The open state is switched to the closed state, and the switch 27gb is switched from the illustrated position, respectively, and as a result, the command signal obtained by the limit control calculation unit 27c as the region limit control is output to the direction switching valves 25a to 25c.

[0047] On the other hand, when the floating predicted value k _d of the vehicle body 10 is determined to have exceeded the determination value H, that it is likely to emerge in the body 10, limit OFF flag F _OFF from floating expected judging unit 27f Therefore, the switch 27ga of the command signal selection unit 27g is switched from the closed state to the open state, and the switches 27gb are switched to the positions shown in the drawings, respectively, and as a result, the area limitation control is released and the operation signal-command signal. Command signals corresponding to the operation signals of the operation lever devices 24a to 24c generated by the conversion unit 27a are output to the direction switching valves 25a to 25c.

According to the present embodiment constructed as described above, the following effects can be obtained. That is, when the vehicle body 10 is in an unreasonable posture on a slope or the like and is about to float up while the area limiting control is working, the area limiting control is automatically released, so that the operator operates the operation lever devices 24a to 24a. By operating 24c, the front working device 10C can be freely moved to quickly avoid the possibility that the vehicle body 10 will float. In addition, after the region restriction control is released, the vehicle body 10
When there is no possibility that the surface will disappear, the operator automatically returns to the area limitation control.
It is not necessary to instruct the area restriction control again by 9, so that the burden on the operator is reduced.

Further, since the operator can arbitrarily set the judgment value H by the judgment value setting switch 21, for example, normally the work is carried out with the judgment value H = 0.5, and a stable place such as a wetland where the feet are unstable. Since the possibility of ascending will increase when working in, the decision value H = 0.4 is set to release the area restriction control earlier, and when working in a place where you do not want to release the area restriction control, such as a narrow place, the judgment value It is possible to change the determination value H according to the work situation, such as setting H = 0.6 and delaying the release of the region restriction control.

In this embodiment, the inclination angle θ of the vehicle body 10
_The calculation for predicting the levitation of the vehicle body 10 is performed based on _a , the turning angle θ _t of the upper revolving structure 10B, and the position and orientation of the front working device 10C, but the levitation prediction of the vehicle body 10 is not limited to this. It may be calculated based on only the 10 inclination angle theta _a of, or may be calculated based on the turning angle theta _t tilt angle theta _a and the upper revolving structure 10B of the body 10, or the inclination angle of the vehicle body 10 theta _a and front working device 10C
May be calculated based on the position and orientation of the above, and may be calculated based on only the turning angle θ _t of the upper swing body 10B.

Further, in this embodiment, the front working device 1 is used.
The bucket tip data included in the front position information _If as the position and posture of 0C, that is, the distance L _BK between the pivot fulcrum of the boom 10a and the tip of the bucket 10c is used.
In addition to this, the weight of the bucket 10c is detected, and the weight is calculated from the weight of the bucket 10c and the distance L _BK between the rotation fulcrum of the boom 10a and the tip of the bucket 10c. It is also possible to use the moment applied to the work device 10C to calculate the floating prediction of the vehicle body 10.

The second embodiment of the present invention will be described with reference to FIGS. In this embodiment, the determination value H is changed based on the bottom pressure of the boom cylinder 23a. In the figure, the members shown in FIG. 1 and those having the same functions as those shown in FIG.

In FIG. 9, the area limitation control device of this embodiment has the configuration shown in FIG.
It has a pressure sensor 29 instead of. Pressure sensor 2
9 detects the bottom pressure P _BM of the boom cylinder 23a and outputs it to the controller 27A.

FIG. 10 shows a functional block diagram of the controller 27A of this embodiment. It differs from the first embodiment only in the judgment value setting unit 27e *, and is otherwise the same. Judgment value setting unit 2
7e * predicts the load applied to the front working device 10C based on the bottom pressure P _BM of the boom cylinder 23a from the pressure sensor 29. For example, when the bottom pressure P _BM is high, it is determined that heavy excavation is likely to occur. Then, the determination value H is reduced so that the area limitation control can be released earlier.

Also in this embodiment, as in the case of the first embodiment, when the vehicle body 10 is about to float, the operator can freely move the front working device 10C to quickly avoid the possibility of floating. In addition, it is not necessary for the operator to instruct the area limitation control again when the possibility that the vehicle body 10 will float up disappears. Further, the judgment value H is automatically changed according to the work situation, so that
Since it is not necessary to perform the setting operation, the burden on the operator is reduced.

In this embodiment, the boom cylinder 23
Although the determination value H is changed based on the bottom pressure P _BM of a, it is not limited to this and may be changed based on the rod pressure of the boom cylinder 23a. Also, the arm cylinder 2
3b, the bottom pressure of the arm cylinder 23c or the rod pressure may be changed.

Further, in the above embodiments, the electric operation system is used as the operation lever devices 24a to 24c and the direction switching valves 25a to 25c, but the invention is not limited to this, and a hydraulic pilot type may be used. In this case, the operating lever device 24a
.About.24c and the directional control valves 25a to 25c are provided with a sensor for detecting the pilot pressure and an electromagnetic pressure reducing valve for controlling the pilot pressure in the pilot circuit, and the controller 27; Accordingly, the electromagnetic pressure reducing valve may be controlled to control the pilot pressure.

[0058]

According to the present invention, when the area limiting control is working, the operator does not need to perform the operation of releasing the area limiting control even when he / she wants to quickly release the area limiting control according to work needs. Therefore, the area limitation control ability can be quickly released.

[Brief description of drawings]

FIG. 1 is a diagram showing an area limitation control device for a construction machine according to a first embodiment of the present invention together with a hydraulic drive system thereof.

FIG. 2 is an element diagram of a hydraulic excavator to which the present invention is applied.

FIG. 3 is a diagram showing a restricted area set by an area restriction control device of the present invention.

4 is a functional block diagram of the controller shown in FIG. 1. FIG.

5 is a diagram showing a posture of the hydraulic excavator shown in FIG. 2 when the vehicle body is tilted.

FIG. 6 is a diagram showing the center of gravity of the front working device of the hydraulic excavator shown in FIG. 2.

FIG. 7 is a flowchart showing control functions of the controller shown in FIG.

FIG. 8 is a flowchart showing a floating prediction process of a control function of the controller shown in FIG.

FIG. 9 is a diagram showing a region limitation control device for a construction machine according to a second embodiment of the present invention together with a hydraulic drive system thereof.

FIG. 10 is a functional block diagram of the controller shown in FIG.

[Explanation of symbols]

 10 Vehicle Body 10A Lower Traveling Body 10B Upper Revolving Body 10C Front Working Device 10a Boom 10b Arm 10c Bucket 11 Boom Angle Sensor 12 Arm Angle Sensor 13 Bucket Angle Sensor 14 Tilt Sensor 15 Swing Angle Sensor 21 Judgment Value Setting Switch 23a Boom Cylinder 23b Arm Cylinder 23c Bucket cylinder 27, 27A Controller 27a Operation signal-command signal converter 27b Front position calculator 27c Limit control calculator 27d Levitation prediction calculator 27e, 27e * Judgment value setting part 27f Lifting prediction judgment part 27g Command signal selection part 29 Pressure Sensor

Claims (10)

[Claims] 1. An articulated front working device including a lower traveling body, an upper revolving body attached to the lower traveling body so as to be rotatable, and a plurality of front working members attached to the upper revolving body. Equipped to the vehicle body having
In a region limitation control device for a construction machine, which sets a movable region of the front working device and performs a region limiting control so that the front working device moves only within the set region, (a) detecting means for detecting a state quantity of the vehicle body (B) a judging means for judging whether or not the vehicle body may float based on the state quantity of the vehicle body detected by the detecting means; and (c) a vehicle body may float by the judging means. And a control means for canceling the area limitation control when it is determined that the area limitation control apparatus for the construction machine. 2. The area limitation control device for a construction machine according to claim 1, wherein the control means, after canceling the area limitation control, determines that the vehicle body is not likely to levitate. Returns to the area limitation control described above. 3. The area limitation control device for a construction machine according to claim 1, wherein the detecting means has a means for detecting an inclination of the vehicle body, and the judging means is based on a detected value of the inclination of the vehicle body. An area limitation control device for a construction machine, which is means for determining whether or not a vehicle body may float. 4. The area limitation control device for a construction machine according to claim 1, wherein the detection means includes means for detecting inclination of the vehicle body, and means for detecting a state quantity relating to the position and orientation of the front working device. And a means for calculating the position and orientation of the front working device based on the state quantity of the vehicle body, a detected value of the inclination of the vehicle body and a calculated value of the position and posture of the front working device. And a means for determining whether or not the vehicle body may float based on the above. 5. The area limitation control device for a construction machine according to claim 1, wherein the detection means includes means for detecting an inclination of the vehicle body and means for detecting a turning position of the upper swing body. The judging means is means for judging whether or not the vehicle body may float based on the detected value of the inclination of the vehicle body and the detected value of the turning position of the upper swing body. Area limit controller. 6. The area limitation control device for a construction machine according to claim 1, wherein the detection means detects a tilt of the vehicle body and a state quantity related to a position and a posture of the front working device. And a means for detecting a turning position of the upper revolving structure, wherein the judging means calculates a position and a posture of the front working device based on a state quantity of the vehicle body, and detects inclination of the vehicle body. Means for determining whether or not there is a possibility that the vehicle body will float up based on a value, a calculated value of the position and posture of the front working device, and a detected value of the turning position of the upper swing body. Area limit control device for construction machinery. 7. The area limitation control device for a construction machine according to claim 1, wherein the detecting means includes means for detecting inclination of the vehicle body, and means for detecting a state quantity relating to the position and posture of the front working device. And a means for detecting a turning position of the upper revolving structure, wherein the judging means calculates a position and a posture of the front working device based on a state quantity of the vehicle body, and detects inclination of the vehicle body. By dividing the value by the limit inclination angle of the vehicle body to obtain a first intermediate predicted value of the body levitation, and by dividing the calculated values of the position and attitude of the front working device by the limit reach length of the front working device. A second intermediate vehicle body levitation predicted value is obtained, and a third intermediate vehicle body levitation predicted value is obtained by dividing the detected value of the turning position of the upper swing body by the limit turning angle of the upper swing body. First intermediate car A means for calculating a final predicted vehicle levitation value by multiplying the predicted body levitation value, the second intermediate predicted vehicle levitation value, and the third intermediate predicted vehicle levitation value,
A region limitation control device for a construction machine, comprising: a unit that determines that the vehicle body may float when the final predicted vehicle body floating value exceeds a determination value. 8. The area limitation control device for a construction machine according to claim 7, wherein the determination means further includes determination value changing means for changing the determination value. 9. The area limitation control device for a construction machine according to claim 8, wherein the judgment value changing means is a manual setting means capable of arbitrarily setting the judgment value and a setting value by the manual setting means. A region limitation control device for a construction machine, comprising: a unit that changes the determination value. 10. The area limitation control device for a construction machine according to claim 8, wherein the determination value changing means detects a pressure in at least one cylinder of a plurality of cylinders driving the plurality of front working members. An area limitation control device for a construction machine, comprising: a pressure detection means; and a means for changing the determination value according to a detection value of the pressure detection means.