JP3497950B2 - Excavation control device for area limitation of construction machinery - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an area limiting excavation control system for a construction machine, and more particularly to a construction machine such as a hydraulic excavator equipped with a multi-joint type front machine, which is capable of excavating an area in which the front machine can move. The present invention relates to a possible area limiting excavation control device.

[0002]

2. Description of the Related Art A hydraulic excavator is a typical construction machine. In a hydraulic excavator, an operator operates front members such as a boom and an arm that constitute a front device by respective manual operation lever devices. Since these front members are connected to each other by joints and perform a rotational movement, it is not possible to operate these front members to excavate a predetermined region or a predetermined plane.
This is a very difficult task.

Therefore, in order to facilitate the excavation work, there is a proposal of International Publication WO95 / 30059. In this proposal, the excavable area is set, and when a part of the front device, for example, the bucket approaches the boundary of the excavable area, only the movement of the bucket in the direction toward the boundary is decelerated, and the bucket becomes the boundary of the excavable area. When it reaches, the bucket does not go out of the excavable area but can move along the boundary of the excavable area.

[0004]

In the above prior art, when the bucket approaches the boundary of the excavable area, only the movement of the bucket toward the boundary is decelerated so that the bucket can move in the direction along the boundary of the set area. Therefore, excavation with limited area can be performed efficiently and smoothly. However, since the control is speed control, if the command value of the operating lever device is large and the speed of the front device is extremely large, or if the operating lever is moved abruptly, a control response such as a delay on the hydraulic circuit will occur. There was a possibility that the front device would stick out of the setting area due to delay or inertial force applied to the front device.

It is an object of the present invention to provide an area limiting excavation control device for a construction machine capable of efficiently and smoothly excavating an area limited regardless of the operating speed of the front device and the operating state of the operating lever device. .

[0006]

(1) In order to achieve the above object, the present invention provides a plurality of driven members including a plurality of vertically movable front members constituting an articulated front device. A plurality of members, a plurality of hydraulic actuators respectively driving the plurality of driven members, a plurality of operating means for instructing the operation of the plurality of driven members, and driven according to an operation signal of the plurality of operating means, A plurality of hydraulic control valves that control the flow rate of the pressure oil supplied to the plurality of hydraulic actuators, and the plurality of front members include a first flow valve.
A first front member including a front member and a second front member.
Is rotatably connected to the tip side of the second front member.
In an area limiting excavation control system for a construction machine, area setting means for setting a movable area of the front device; first detecting means for detecting a state quantity relating to the position and orientation of the front device; and the first detecting means. the position and posture calculating means for calculating the position and posture of the front device based on signals from, the front device is near the boundary of the set area
If brute, and based on the calculated value of the position and attitude calculation means,
Within the range where the speed of the front device does not become 0,
Signal deceleration control means for reducing an operation signal of at least the operation means relating to the first front member among the operation means of
Wherein when the front device approaches the boundary of the set area, said based on the calculated value of the position and posture computing unit, move in a direction in which the CFC <br/> winding device is along the boundary of the set area, the At least the second one of the plurality of operating means is arranged so that the moving speed is reduced in the direction approaching the boundary of the setting area .
It shall further comprising a deceleration direction change control means to correct the operation signal of the operating means associated to the front member.

In the present invention configured as described above, the deceleration direction conversion control means is set by the front device.
Approaches the boundary of the area, the motion in the direction which the front device along the boundary of the set area, in the direction approaching the boundary of the set region is a manipulation signal of a control unit according to the second front member such that the moving speed is reduced Is corrected to perform deceleration direction conversion control for moving the front device along the boundary of the setting area while reducing the speed of approaching the boundary of the setting area. Therefore, excavation with a limited area can be performed efficiently and smoothly.

Further, in the above deceleration direction conversion control, since the control is speed control, when the speed of the front device is extremely high or when the operating means is rapidly operated near the boundary of the set area, the hydraulic circuit is operated. There is a possibility that the front device may exceed the setting area due to a response delay in control such as an upper delay or an inertial force applied to the front device.

In such a case, in the present invention, the signal deceleration control means does not set the speed of the front device to zero.
Even if the speed of the front device is extremely high or the operating device is operated abruptly, the movement of the front device in the vicinity of the boundary of the set area is prevented by reducing the operation signal of the operating device related to the first front member in the circle. As a result, the influence of the response delay on the control is reduced, and the inertia of the front device is suppressed. Therefore, the amount of the front device penetrating outside the setting area is reduced, and the front device can be smoothly moved along the boundary of the setting area to perform a smooth work.

[0010]

[0011]

(2) In the above (1), preferably,
The signal deceleration control means is configured such that the first deceleration control means reduces the distance between the front device and the boundary of the setting area .
Including a first correction calculating means decreases the amount of the operation signal of the operating means according to the front member to correct the operation signal so as to increase.

As described above, the signal deceleration control unit controls the operation signal so that the decrease amount of the operation signal of the operation unit related to the first front member increases as the distance between the front device and the boundary of the setting region decreases. By correcting, even if the speed of the front device is extremely high or the operating means is operated abruptly, the movement of the front device in the vicinity of the boundary of the set area becomes slow, so the influence of the response delay on the control is affected. The amount of the front device is reduced and the inertia of the front device is suppressed, and the front device can be smoothly moved along the boundary of the setting area. Further, since the speed of the front device is reduced as the front device approaches the boundary of the setting region, when the front device approaches the boundary of the setting region, the operation feeling does not suddenly change and smooth operation can be performed.

[0014]

(3) Further, in the above (2), preferably, the signal deceleration control means performs a second correction calculation for applying a low-pass filter processing to an operation signal of the operation means related to the first front member. Means are further included.

By thus performing the low-pass filter processing on the operation signal of the operation means relating to the first front member , the operation signal at the time of rising when the operation means is rapidly operated in the vicinity of the boundary of the set region is reduced. As a result, even if the operating means is operated suddenly, the front device starts to move slowly, the influence of the response delay in control is reduced, and the inertia of the front device is suppressed.

(4) Further, among the plurality of operating means, at least the operating means relating to the first and second front members is a hydraulic pilot system which outputs pilot pressure as the operating signal. When the operating system including the means drives the corresponding hydraulic control valve, in (1) above, preferably,
The signal deceleration control means calculates a target pilot pressure that becomes smaller as the distance between the front device and the boundary of the setting region becomes smaller, and the pilot pressure given to the hydraulic control valve relating to the first front member is the above-mentioned. means der to correct the pilot pressure output from the operation means according to the first front member such that the lower target pilot pressure or Ru.

As a result, the signal deceleration control can be performed as described in (1) above even when the operating means is the hydraulic pilot system.

[0019]

(5) Further, in the above (4), preferably, the operation system includes a pilot line for guiding a pilot pressure to a hydraulic control valve related to the first front member, and the signal deceleration control means includes the target line. It includes means for outputting an electric signal corresponding to the pilot pressure, and electro-hydraulic conversion means installed in the pilot line and driven by the electric signal.

(6) Further, in the above (1), preferably, the first front member is an arm of a hydraulic excavator, and the second front member is a boom of the hydraulic excavator.

(7) In order to achieve the above object,
The present invention relates to a plurality of driven members including a plurality of vertically rotatable front members that constitute an articulated front device, a plurality of hydraulic actuators that respectively drive the plurality of driven members, and A plurality of operating means for instructing the operation of the plurality of driven members, and a plurality of hydraulic control driven by the operation signals of the plurality of operating means to control the flow rate of the pressure oil supplied to the plurality of hydraulic actuators. A valve , the plurality of front members being a first front member
The second front member is included, and the first front member is the second flow member.
An area limiting excavation control device for a construction machine, which is rotatably connected to the tip of a front member, and area setting means for setting a movable area of the front device; and a state quantity relating to the position and posture of the front device. first detecting means and for, the position and posture calculating means for calculating the position and posture of the front device based on signals from the first detecting means; before
When serial front device approaches the boundary of the set area, based on the calculated value of the position and attitude calculation means, the front
A signal deceleration control means for reducing the operation signal of the operating means associated with at least said first front member among the plurality of operating means to the extent that the speed of the device does not become 0, the front
When the device approaches the boundary of the set area, the signal based on the calculated value of the corrected operation signal in deceleration control means and the position and orientation calculation unit, a direction in which the front device along the boundary of the set area The second flow so that the moving speed is reduced in the direction approaching the boundary of the set area.
And a deceleration direction conversion control means for correcting the operation signal of the operation means related to the mounting member.

[0023] Thus, an operation signal according to the second front member by using the operation signal of the operating means according to the first front member is corrected, in which performs deceleration direction change control, as described above (1), the (1) Since the operation signal of the operating means relating to the front member is reduced, the amount of intrusion of the front device out of the setting area is reduced, and the front device is smoothly moved along the boundary of the setting area to perform a smooth work. You can

(8) In the above (1) and (7) ,
The area limited excavation control device of the present invention preferably has a manual operation section operated by an operator, and the signal decrease amount adjustment for adjusting the decrease amount of the operation signal in the signal deceleration control means by the operation of the manual operation section. Means are further provided.

Depending on the work site, the drilling required
There are various degrees and speeds. Excavation accuracy may be a little poor
Therefore, there are times when you want to increase the work speed,
Even if it is late, there are times when accuracy is required. In the present invention,
As described in (8) above, the means for adjusting the amount of signal reduction is provided to allow manual operation.
The operation signal is reduced by the signal deceleration control means by operating the work unit.
A small amount can be adjusted. For this reason, it is possible to easily set the optimal reduction amount for every work site, and it is possible to improve work efficiency.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention applied to a hydraulic excavator will be described below with reference to the drawings. First,
A first embodiment of the present invention will be described with reference to FIGS.

In FIG. 1, a hydraulic excavator to which the present invention is applied includes a hydraulic pump 2, a boom cylinder 3a driven by pressure oil from the hydraulic pump 2, an arm cylinder 3b, a bucket cylinder 3c, a swing motor 3d, and a swing motor 3d. A plurality of hydraulic actuators including the left and right traveling motors 3e and 3f, and a plurality of operating lever devices 4a to 4 provided corresponding to the hydraulic actuators 3a to 3f, respectively.
f, the hydraulic pump 2, and the plurality of hydraulic actuators 3a to
A plurality of flow rate control valves 5a connected between 3f and controlled by the operation signals of the operation lever devices 4a to 4f to control the flow rate of the pressure oil supplied to the hydraulic actuators 3a to 3f.
To 5f, and a relief valve 6 that opens when the pressure between the hydraulic pump 2 and the flow control valves 5a to 5f exceeds a set value, and these are hydraulic drive devices that drive the driven members of the hydraulic excavator. Are configured.

As shown in FIG. 2, the hydraulic excavator comprises a multi-joint type front device 1A consisting of a boom 1a, an arm 1b and a bucket 1c which rotate in the vertical direction, an upper revolving structure 1d and a lower traveling structure 1e. The boom 1a of the front device 1A is supported by the front portion of the upper swing body 1d. The boom 1a, the arm 1b, the bucket 1c, the upper swing body 1d and the lower traveling body 1e are respectively a boom cylinder 3a and an arm cylinder 3
b, a bucket cylinder 3c, a turning motor 3d, and left and right traveling motors 3e and 3f, which are driven members, respectively, and their operation is performed by the operation lever device 4a.
~ 4f.

The operation lever devices 4a to 4f are of a hydraulic pilot type, and the pilot pressures corresponding to the operation amounts and the operation directions of the operation levers 40a to 40f operated by the respective operators are supplied to the pilot lines 44a to 49b.
The hydraulic drive unit 5 of the corresponding flow rate control valves 5a to 5f via the
0a to 55b to drive these flow rate control valves.

The hydraulic excavator as described above is provided with the area limiting excavation control system according to this embodiment. This control device has a region setting switch 7a for instructing the setting of an excavable region in which a predetermined portion of the front device, for example, the tip of the bucket 1c can move in advance, and a control start switch 7b for instructing the start of the region limiting excavation control. And a deceleration amount adjuster 70 for instructing a change in the reduction amount of an operation signal for lever signal deceleration control (described later), and a pivot 1 of the boom 1a, arm 1b, and bucket 1c. Angle detectors 8a and 8a for detecting respective rotation angles as state quantities related to the position and orientation of the front device 1A.
b, 8c, an inclination angle detector 8d for detecting the inclination angle of the vehicle body 1B in the front-rear direction, and pilot lines 45a, 45b of the operation lever device 4b for the arm, and the pilot pressure is used as the operation amount of the operation lever device 4b. Of the pressure detectors 61a and 61b for detecting the pressure, and the primary port side of the pilot pump 43 are connected to the pilot pump 4 according to the electric signal.
Proportional solenoid valve 1 that reduces the pilot pressure from 3 and outputs it
0a, the pilot line 44a of the operating lever device 4a for the boom, and the secondary port side of the proportional solenoid valve 10a, and the pilot pressure in the pilot line 44a and the high pressure side of the control pressure output from the proportional solenoid valve 10a are connected to each other. The shuttle valve 12 that selects and guides the hydraulic drive unit 50a of the flow control valve 5a
And the pilot lines 44b of the boom operation lever device 4a and the pilot lines 45a, 45b of the arm operation lever devices 4a, 4b, respectively, for reducing the pilot pressure in each pilot line according to an electric signal. Proportional solenoid valves 10b, 11a, 1 for outputting
1b, pressure detectors 61a and 61b installed on the pilot lines 45a and 45b on the primary port side of the proportional solenoid valves 11a and 11b, for detecting respective pilot pressures as operation amounts of the operation lever device 4b, and the proportional solenoid valve 1
Proportional solenoid valves 11a, 11b are installed on pilot lines 45a, 45b on the secondary port side of 1a, 11b.
Pressure detectors 61c, 61 for detecting the pilot pressure applied to the hydraulic drive units 51a, 51b of the flow control valve 5b from
d, operation signals of the operation lever devices 4a to 4f, area setting switch 7a, control start switch 7b and instruction signal of deceleration amount adjuster 70, detection signals of angle detectors 8a, 8b, 8c and inclination angle detector 8d, Pressure detectors 61a, 61b, 6
The detection signals of 1c and 61d are input to set the excavable region in which the tip of the bucket 1c can move, and the proportional solenoid valves 10a and 10b are used as electrical signals for correcting the operation signal for performing the excavation control in which the region is limited. , 11a, 11b, and a control unit 9 for outputting the signals.

The setting device 7 is provided on the operation panel or the grip, and instructs the control unit 9 to set the excavation area by pressing the area setting switch 7a and presses the control start switch 7b to perform the area limiting excavation control. Is to instruct the start of. There may be other auxiliary means such as a display device on the setting device 7. In addition, the instructions for setting the excavation area are based on an IC card method, a bar code method,
Other methods such as a laser method and a wireless communication method may be used.

The deceleration amount adjuster 70 is also provided on the operation panel, for example, and as shown in FIG. 1 to 5 adjustment buttons 71 to 75 and corresponding LEDs 76 to 8
1 and. When the control is started, No. The arm speed at position 3 is set, and the LED is also the LED at position 3.
79 is lit. No. As the adjustment buttons 74 and 75 at the positions of 4 and 5 are pressed, the reduction amount of the operation signal of the lever signal deceleration control (described later) decreases, and the arm speed in the deceleration region (described later) increases. 2,1 adjustment button 7
As 2, 71 are pressed, the amount of decrease in the operation signal of the lever signal deceleration control increases, and the arm speed in the deceleration region decreases. The LEDs 76 to 81 light up corresponding to the pressed button.

The control function of the control unit 9 is shown in FIG.
The control unit 9 includes a front posture calculation unit 9a, a region setting calculation unit 9b, a bucket tip speed limit value calculation unit 9c, an arm cylinder speed calculation unit 9d, an arm bucket tip speed calculation unit 9e, and a boom tip speed limit. Value calculator 9f, boom cylinder speed limit value calculator 9
g, boom pilot pressure limit value calculator 9h, area limit control switching calculator 9r, boom valve command calculator 9i, lever signal deceleration control calculator 9m, lever signal reduction amount calculator 9n, lever signal deceleration control It has the respective functions of the switching calculation unit 9s and the arm valve command calculation unit 9k.

The front attitude calculation unit 9a determines the position of the front device 1A based on the rotation angles of the boom, arm and bucket detected by the angle detectors 8a to 8c and the inclination angle detector 8d and the front and rear inclination angles of the vehicle body 1B. Calculate the posture. One example thereof will be described with reference to FIG. This example is front device 1A
This is a case where the position of the toe (tip) P ₁ of the bucket is calculated, and the detection value of the inclination angle detector 8d is omitted for simplification of the description.

In FIG. 5, the storage unit of the control unit 9 stores the respective dimensions of the front device 1A and the vehicle body 1B. The front attitude calculation unit 9a uses these data and the angle detectors 8a, 8b and 8c. Detected rotation angle α,
The value of β and γ is used to calculate the position of the bucket tip P ₁ . At this time, the position of P ₁ is obtained as the coordinate value (X, Y) of the XY coordinate system with the rotation fulcrum of the boom 1a as the origin. The XY coordinate system is an orthogonal coordinate system in a vertical plane fixed to the main body 1B. Rotation fulcrum of boom 1a and arm 1b
L ₁ the distance between the pivot point of, if the distance between the pivot point of the pivot point and the bucket 1c of the arm 1b L _2, the distance between the tip of the pivot point and the bucket 1c of the bucket 1c and L ₃ ,
Coordinate values (X, Y) in the XY coordinate system from the rotation angles α, β, γ
Is calculated from the following formula.

X = L ₁ sin α + L ₂ sin (α + β) +
L ₃ sin (α + β + γ) Y = L ₁ cos α + L ₂ con (α + β) + L ₃ cos (α
+ Β + γ) When the control start switch 7a of the setter 7 is turned on (pressed), the area setting calculation unit 9b sets a value at a deep position that the bucket does not reach as an initial value of the boundary L of the excavable area. As a result, immediately after the control start switch 7a is turned on, the front device 1A can freely move within the range in which it can operate, and the excavable region can be freely set within the operating range by direct teaching. . As an example, the initial value is Y = -20 m.

In addition, the area setting calculation unit 9b performs setting calculation of the excavable area in which the tip of the bucket 1c can move by direct teaching in response to an instruction from the area setting switch 7b. One example thereof will be described with reference to FIG. In this example, the boundary L of the excavable area is set as a straight line parallel to the X axis of the depth h1.

In FIG. 5, after the operator moves the tip point P ₁ of the bucket 1c to the target position, the area setting switch 7b is pressed. When the area setting switch 7b is pressed, the area setting calculation unit 9b calculates the value Y of the Y coordinate value of the bucket tip P1 calculated by the front attitude calculation unit 9a at that time.
= Y ₁ is used to set the setting value = Y coordinate value Y ₁ and the boundary L of the excavable area. Then, after setting the boundary L of the excavable area in this way, a straight line formula of the boundary L of the set excavable area is established, and an orthogonal coordinate system XaYa coordinate system having an origin on the straight line and having the straight line as one axis is set. Vertically, the conversion data from the XY coordinate system to the XaYa coordinate system is obtained.

The bucket tip speed limit value calculation unit 9c calculates the limit value a of the component perpendicular to the bucket tip speed boundary L based on the distance D from the bucket tip boundary L. This is performed by storing the relationship shown in FIG. 6 in the storage device of the control unit 9 and reading the relationship.

In FIG. 6, the horizontal axis shows the distance D from the boundary L of the bucket tip, the vertical axis shows the limit value a of the component perpendicular to the boundary L of the bucket tip speed, the distance D of the horizontal axis and the vertical axis. As for the speed limit value a, the direction from the outside of the setting area to the inside of the setting area is the (+) direction, as in the XaYa coordinate system. The relationship between the distance D and the limit value a is that, when the bucket tip is within the set area, the velocity in the (-) direction proportional to the distance D is the limit value a of the component perpendicular to the boundary L of the bucket tip velocity, When the tip of the bucket is outside the region, the velocity in the (+) direction proportional to the distance D is set as the limit value a of the component perpendicular to the boundary L of the velocity of the bucket tip. Therefore, within the setting area, the bucket tip speed is decelerated only when the component perpendicular to the boundary L in the (-) direction exceeds the limit value, and outside the setting area, the bucket tip is accelerated in the (+) direction. Like

The arm cylinder speed calculator 9d uses the command value (pilot pressure) to the flow rate control valve 5b detected by the pressure detectors 61c and 61d and the flow rate characteristic of the flow rate control valve 5b of the arm to control the arm cylinder for control. Estimate the speed.

Bucket tip speed calculator 9e by arm
Then, the bucket tip speed b by the arm is calculated from the arm cylinder speed and the position and attitude of the front device 1A obtained by the front attitude calculation unit 9a.

In the bucket tip speed limit value calculation unit 9f for the boom, the bucket tip speed b by the arm calculated by the calculation unit 9e is converted from the XY coordinate system to the XaYa coordinate system using the conversion data calculated by the area setting calculation unit 9b. The bucket tip speed (bx, by) of the arm is calculated, and the limit value a of the component perpendicular to the boundary L of the bucket tip speed obtained by the calculation unit 9c and the boundary L of the bucket tip speed of the arm are perpendicular. With the component by, the limit value c of the component perpendicular to the boundary L of the bucket tip speed due to the boom is calculated. This will be described with reference to FIG.

In FIG. 7, the limit value a of the component perpendicular to the boundary L of the bucket tip speed calculated by the bucket tip speed limit calculation section 9c and the bucket tip speed by the arm calculated by the arm bucket tip speed calculation section 9e. b
Difference (a-by) of the component by perpendicular to the boundary L of the bucket is the limit value c of the component perpendicular to the boundary L of the bucket tip speed of the boom.
Thus, the limit value calculation unit 9f for the bucket tip speed due to the boom calculates the limit value c from the equation c = a-by.

The meaning of the limit value c will be described separately for the case where the tip of the bucket is within the set area, is on the boundary, and is outside the set area.

When the bucket tip is within the set area, the bucket tip speed is the distance D from the boundary L of the bucket tip.
In proportion to the limit value a of the component perpendicular to the boundary L of the bucket tip speed, and the component perpendicular to the boundary L of the bucket tip speed due to the boom is limited to c (= a-by). If the component by of the speed b perpendicular to the boundary L exceeds this, the speed is reduced to c.

When the bucket tip is on the boundary L of the set area, the limit value a of the component perpendicular to the boundary L of the bucket tip speed is 0, and the bucket tip speed b by the arm moving out of the set area is the speed c. It is canceled by the correction operation by raising the boom, and the component by perpendicular to the boundary L of the bucket tip speed becomes zero.

When the bucket tip is out of the range, the component of the bucket tip speed perpendicular to the boundary L is limited to the upward speed a proportional to the distance D from the boundary L of the bucket tip, so that the setting area is always set. The correction operation is performed by raising the boom at the speed c so as to restore the inside.

In the boom cylinder speed limit value calculation unit 9g, coordinate conversion using the above conversion data is performed based on the limit value c of the component perpendicular to the boundary L of the bucket tip speed due to the boom and the position and orientation of the front device 1A. Calculate the boom cylinder speed limit value.

The boom pilot pressure limit calculation unit 9h obtains a boom pilot pressure limit value corresponding to the boom cylinder speed limit value obtained by the calculation unit 9g, based on the flow rate characteristic of the boom flow rate control valve 5a.

In the area limiting control switching arithmetic unit 9r,
When the control start switch 7b is ON (pressed) and the start of the area limiting excavation control is instructed, the value calculated by the calculation unit 9h as the boom pilot pressure limit value is output as it is, and the control start switch 7b is output. Is OFF (not pressed) and the start of the area limiting excavation control is not instructed, the maximum value of the boom pilot pressure is output.

In the boom valve command calculation unit 9i, the limit value of the pilot pressure is input from the calculation unit 9r, and when this value is positive, the proportional solenoid valve 10a on the boom raising side receives a voltage corresponding to the limit value. Is output, the pilot pressure of the hydraulic drive unit 50a of the flow control valve 5a is limited to the limit value, and a voltage of 0 is output to the proportional solenoid valve 10b on the boom lowering side. When the limit value is negative, a voltage corresponding to the limit value is output to the proportional solenoid valve 10b on the boom lowering side, and the flow control valve 5
The pilot pressure of the hydraulic drive unit 50b of a is limited to the limit value, and a voltage of 0 is output to the proportional solenoid valve 10a on the boom raising side.

The lever signal deceleration control calculation section 9m performs a lever signal deceleration process for reducing the operation signal (pilot pressure) of the operation lever device 4b for the arm of the front device 1A.

FIG. 8 is a flowchart showing the processing contents of the lever signal deceleration controller 9m. First, in step 110, the tip position of the bucket 1c in the XY coordinate system obtained by the front posture calculation unit 9b is converted into a value in the XaYa coordinate system using the conversion data obtained by the region setting calculation unit 9a, and the Ya
The distance D between the tip position and the boundary of the setting area in the setting area is obtained from the coordinate values. Next, in step 130, the time constant tg is calculated using the relationship between the distance D with the tip of the bucket 1c and the time constant tg as shown in FIG. 9, and the distance D and the lever signal deceleration as shown in FIG. The deceleration coefficient hg is calculated using the relationship with the coefficient hg.

The relationship between the distance D and the time constant tg shown in FIG. 9 is stored in the storage device of the control unit 9.
The relationship between the distance D and the time constant tg is that the distance D is the distance Ya.
When it is larger than 1, tg = 0, and when D becomes smaller than Ya1, the time constant tg increases as the distance D decreases, and tg = tgmax is set at the distance D = 0. .

Further, the relationship between the distance D and the lever signal deceleration coefficient hg shown in FIG.
Given more. The relationship between the distance D and the deceleration coefficient hg is hg = 1 when the distance D is larger than the distance Ya1, and when the distance D becomes smaller than Ya1, the deceleration coefficient hg becomes as the following formula as the distance D decreases. , Hg = Csin (θg) · D + hgmin, and becomes smaller at a distance D = 0 and hg = hgmi
It is set to be n. Here, C is the gradient of the deceleration coefficient, and hgmin is the value of the cut edge of the deceleration coefficient, which is an adjustable constant (described later). Further, θg is shown in FIG.
As shown in, the line segment connecting the tip of the bucket 1c and the arm pin (where the angle detector 8b is attached), which is the center of rotation of the arm 1b, is the angle formed by the boundary of the excavation region.

In step 130, the time constant tg and the deceleration coefficient hg at that time are calculated from the distance D obtained in step 110 and the relationships shown in FIGS. 9 and 10. At this time, the coefficient hg is a function of the angle θg formed by the line segment connecting the tip of the bucket 1c and the center of rotation of the arm 1b with the boundary of the excavation area as described above. This angle θg
Ask for. The angle θg is the detected rotation angles α, β, γ and the front device 1 stored in the storage device of the control unit 9.
The position of the tip of the bucket 1c and the position of the center of rotation of the arm 1b are obtained based on the dimensions of each part of A, and the value of this position and the linear expression of the boundary L of the set area obtained by the area setting section are obtained.

Next, the pilot pressures as arm operation signals detected by the pressure detectors 61a and 61b are set to Pa and Pb.
Then, in step 140, the pilot pressures Pa and Pb are low-pass filtered using the time constant tg to generate the corrected pilot pressures Pa1 and Pb1.

Here, the calculation formula of the low-pass filter processing performed in step 140 is as follows.

Output = x _n-1 + (1−e ^−aT ) (x _n −x _n−1 ) where x _{n is} the operation signal input at the current sampling time x _{n−1 is the} previous sampling time Output value a = 1 / tg T = step time In this way, in step 140, pilot pressures Pa, Pb
Performing the low-pass filter process with respect to the above means to delay the rise of the signal with respect to the stepwise signal input as shown in FIG. 11, and apparently the lever operation is performed slowly. Further, increasing the time constant tg when performing the low-pass filter processing as the distance D decreases makes the rise of the signal (pilot pressure) slower as the tip of the bucket 1c approaches the boundary L of the excavation region. Therefore, as the tip of the bucket 1c approaches the boundary L of the excavation area, the amount of decrease at the time of rising of the signal increases. Next, in step 150,
The speeds VAC1 and VAD1 of the arm cylinder 3b corresponding to the corrected pilot pressures Pa1 and Pb1 are calculated from the cylinder speed characteristics of the flow rate control valve 5b of the arm shown in FIG.

Next, in step 160, the maximum value V of the cloud side cylinder speed of the arm cylinder 3b stored in the storage device of the control unit 9 as shown in FIG.
ACmax and the minimum value VADm of the cylinder speed on the dump side
In (maximum absolute value) is multiplied by the above-described deceleration coefficient hg to generate a correction maximum value VAC2 and a correction minimum value VAD2 of the arm cylinder speed.

Then, in step 170, VAC1,
The minimum value of VAC2 is the cloud side target cylinder speed VAC of the arm cylinder 3b, and the maximum value of VAD1 and VAD2 (the minimum absolute value of VAD1 and VAD2) is the dump side target cylinder speed VAD of the arm cylinder 3b. That is, VAC1> VAC2, VAD1 <VAD
When it is 2, VAC2 and VAD2 are selected, and the maximum and minimum values of the target cylinder speeds VAC and VAD are limited to the correction maximum value VAC2 and the correction minimum value VAD2, respectively.

Here, in step 160, the maximum value VACmax and the minimum value VADmin of the cylinder speed are multiplied by the deceleration coefficient hg to generate the corrected maximum value VAC2 and the corrected minimum value VAD2 of the cylinder speed. It means that the absolute value of the correction maximum value VAC2 and the correction minimum value VAD2 decreases as the tip of the bucket 1c approaches the boundary of the excavation area. Further, hg is a sin function of the angle θg formed by the line segment connecting the tip of the bucket 1c and the center of rotation of the arm 1b as described above, and θg
As hg becomes smaller as becomes smaller, the correction maximum value VAC2 becomes larger as the front device 1A extends.
Also, the absolute value of the correction minimum value VAD2 becomes smaller.

Therefore, when VAC2 and VAD2 are selected as the target cylinder velocities VAC and VAD in step 170, the target pilot pressure is increased as the tip of the bucket 1c approaches the boundary of the excavation area and as the front device 1A extends. The decrease amount of Pa2 and Pb2 becomes large. On the other hand, target cylinder speeds VAC, VA
When VAC1 and VAD1 are selected as D,
As described above, the low-pass filter processing is performed on the pilot pressures Pa and Pb, and as the tip of the bucket 1c approaches the boundary L of the excavation region, the amount of decrease at the time of rising of the signal increases. Next, in step 180, the pilot line 45 is changed from the target cylinder speeds VAC, VAD
The target pilot pressures Pa2 and Pb2 of a and 45b are calculated. This is an inverse operation of the operation for obtaining the arm cylinder speed in step 150.

The lever signal reduction amount adjustment calculation unit 9n sets the lever signal deceleration coefficient hg according to which of the adjustment buttons 71 to 75 of the deceleration amount adjuster 70 is pressed.

FIG. 13 shows a lever signal decrease amount adjustment calculation unit 9n.
The processing content of is shown in a flowchart. First, step 250
When the control start switch 7b is pressed at No. 3, the deceleration amount adjuster No. The deceleration coefficient hg corresponding to the third adjustment button 73 is set as an initial value. Then, step 27
At 0, it is determined whether any of the adjustment buttons 71 to 75 has been pressed, and if any of them is pressed, in step 280, the deceleration coefficient hg corresponding to the pressed adjustment button is set.

FIG. 14 shows the respective deceleration coefficients set when the adjustment buttons 71 to 75 are pressed. "1" is the deceleration coefficient hg when the adjustment button 71 is pressed, "2"
Is the deceleration coefficient hg when the adjustment button 72 is pressed,
“3” is the deceleration coefficient h when the adjustment button 73 is pressed.
g, “4” is the deceleration coefficient hg when the adjustment button 74 is pressed, and “5” is the deceleration coefficient hg when the adjustment button 75 is pressed, which are set as follows.

1: hg = C ₁ sin (θg) · D + hgmin ₁ 2: hg = C ₂ sin (θg) · D + hgmin ₂ 3: hg = C ₃ sin (θg) · D + hgmin ₃ 4: hg = C ₄ sin ( _{θg) · D + hgmin 4 5} : hg = C 5 sin (θg) · D + hgmin 5 C 1 ~C 5, hgmin 1 ~hgmin 5 is stored in the storage device in advance the control unit 9.

By selecting and setting the deceleration coefficient hg with the adjusting buttons 71 to 75 in this way, the reduction amount of the operation signal calculated from the deceleration coefficient hg by the lever signal deceleration control calculation unit 9m can be adjusted, and the lever signal can be adjusted. The arm speed in deceleration control can be adjusted.

The lever signal deceleration control switching arithmetic unit 9s switches the value calculated by the arithmetic unit 9m according to whether or not the tip of the bucket 1c is in the deceleration region and whether the control start switch 7b is turned on or off. Output. The details are shown in the flow chart of FIG.

In FIG. 15, first, in step 300, it is judged whether or not the control start switch 7b is pressed, and if it is pressed, the process proceeds to step 310. In step 310, it is determined whether the tip of the bucket 1c has entered the deceleration area. In the storage device of the control unit 9, a distance Ya1 from the boundary L of the set area as shown in FIG. 7 is stored as a value for setting the range of the deceleration area. Step 310
Then, if the distance D obtained in step 110 of the lever signal deceleration control calculation unit 9m becomes smaller than the distance Ya1, it is determined that the vehicle has entered the deceleration region. In step 310, bucket 1c
If it is determined that the front end of the
0, and the calculation unit 9 sets the limit value of the arm pilot pressure.
The value calculated in m is output as it is. When the distance D becomes a negative value, the target pilot pressure calculated when D = 0 continues to be output as the limit value of the arm pilot pressure. On the other hand, if the control start switch 7b is not pressed in step 300, or if the distance D is larger than the distance Ya1 in step 310 and the tip position of the bucket 1c has not entered the deceleration region, the process proceeds to step 330 and the arm pilot The maximum value is output as the pressure limit value.

In the arm valve command calculation unit 9k, the limit value of the arm pilot pressure is input from the calculation unit 9s, and when this value is positive, the proportional solenoid valve 1 on the arm cloud side 1
The voltage corresponding to the limit value is output to 1a, and the flow control valve 5b
The pilot pressure of the hydraulic drive unit 51a is set to the limit value,
A voltage of 0 is output to the proportional solenoid valve 11b on the arm dump side. When the limit value is negative, a voltage corresponding to the limit value is output to the proportional solenoid valve 11b on the arm dump side, the pilot pressure of the hydraulic drive unit 51b of the flow control valve 5b is set to the limit value, and the arm crowding is performed. 0 for the proportional solenoid valve 11a on the side
Output the voltage.

The operation of this embodiment configured as described above will be described. This explanation turns on the control start switch 7b.
However, this is a case of performing the area limiting excavation control. In addition, as an example of the work, when the boom is lowered by operating the operation lever of the boom operation lever device 4a in order to position the tip of the bucket and the boom is lowered (boom lowering operation), the arm is used for excavating in the front direction. A case where the operation lever of the operation lever device 4b is operated in the arm crowd direction to perform arm crowding (arm crowd operation) will be described.

When the operation lever of the boom operation lever device 4a is operated in the boom lowering direction in order to position the tip of the bucket, the pilot pressure, which is the command value of the operation lever device 4a, is transmitted through the pilot line 44b. 5a is provided to the hydraulic drive unit 50b on the boom lowering side. On the other hand, at the same time, in the calculation unit 9c, the distance D from the bucket tip and the boundary L between the set areas is calculated from the relationship shown in FIG.
The bucket tip speed limit value a (<0) proportional to the bucket tip speed is calculated in the calculation unit 9f, and the boom tip speed limit value c = a (<0) is calculated in the calculation unit 9f. Then, the limit value of the negative boom command is calculated according to the limit value c, and the valve command calculator 9i limits the voltage corresponding to the limit value so as to limit the pilot pressure of the hydraulic drive unit 50b of the flow control valve on the boom lowering side. Is output to the proportional solenoid valve 10b, a voltage of 0 is output to the proportional solenoid valve 10a on the boom raising side, and the pilot pressure of the hydraulic drive unit 50a of the flow control valve 5a is set to zero. At this time, when the bucket tip is far from the boundary L of the set region, the absolute value of the limit value of the boom pilot pressure obtained by the calculation unit 9h is large, and the pilot pressure of the operating lever device 4a is smaller than this, so the proportional electromagnetic The valve 10b outputs the pilot pressure of the operation lever device 4a as it is, whereby the boom is lowered according to the pilot pressure of the operation lever device 4a.

As described above, as the boom is lowered and the bucket tip approaches the boundary L of the set area, the limit value c = a of the bucket tip speed by the boom calculated by the computing unit 9f.
(<0) becomes large (| a | or | c | becomes small), and the absolute value of the corresponding boom command limit value (<0) obtained by the computing unit 9h becomes small. When the absolute value of the limit value becomes smaller than the command value of the operating lever device 4a and the voltage output from the valve command calculation unit 9i to the proportional solenoid valve 10b becomes smaller accordingly, the proportional solenoid valve 1
0b depressurizes and outputs the pilot pressure of the operating lever device 4a, and the hydraulic drive unit 50 on the boom lower side of the flow control valve 5a.
The pilot pressure applied to b is gradually limited according to the limit value c. As a result, the boom lowering speed is gradually limited as it approaches the boundary L of the setting area, and the boom stops when the tip of the bucket reaches the boundary L of the setting area. Therefore, the bucket tip can be easily and smoothly positioned.

When the tip of the bucket extends beyond the boundary L of the set area, the calculation unit 9c determines the limit value of the bucket tip speed proportional to the distance D from the boundary L between the bucket tip and the set area from the relationship shown in FIG. a (= c) is calculated as a positive value, and the valve command calculation unit 9i outputs a voltage corresponding to the limit value c to the proportional solenoid valve 10a and limits it to the hydraulic drive unit 50a of the boom raising side flow control valve 5a. A pilot pressure corresponding to the value a is given. As a result, the boom is moved in the raising direction so as to restore into the area at a speed proportional to the distance D, and stops when the tip of the bucket returns to the boundary L of the set area. Therefore, the bucket tip can be positioned more smoothly.

When the operation lever of the arm operation lever device 4b is operated in the arm crowd direction in an attempt to excavate in the front direction, the pilot pressure (described later) output from the proportional solenoid valve 11a is applied to the arm crowd side of the flow control valve 5b. Is applied to the hydraulic drive unit 51a of FIG. 1 and the arm is moved downward.

On the other hand, at the same time, the pilot pressure (proportional solenoid valve 1) applied to the hydraulic drive unit 51a of the flow control valve 5b is supplied.
The output pressure of 1a) is detected by the pressure detector 61c and is input to the calculation unit 9d to calculate the arm cylinder speed, and the calculation unit 9e calculates the bucket tip speed b by the arm. Further, the calculation unit 9c calculates a limit value a (<0) of the bucket tip speed proportional to the distance D from the bucket tip and the boundary L between the set areas from the relationship shown in FIG.
Then, the limit value of the bucket tip speed due to the boom c = ab
y is calculated. At this time, when the bucket tip is far from the boundary L of the set region and a <by (| a |> | by |), the limit value c is calculated as a negative value, and the valve command calculation unit 9i determines that the boom lowering side is set. Hydraulic drive unit 50b of flow control valve
A voltage corresponding to the limit value is output to the proportional solenoid valve 10b so as to limit the pilot pressure, and a voltage of 0 is output to the proportional solenoid valve 10a on the boom raising side to pilot the hydraulic drive unit 50a of the flow control valve 5a. Set pressure to 0. At this time, since the operation lever device 4a is not operated, the flow control valve 5
No pilot pressure is output to the hydraulic drive unit 50b of a. As a result, the arm is moved in the front direction according to the pilot pressure applied to the hydraulic drive unit 51a of the flow rate control valve 5b.

As described above, as the arm is moved toward the front side and the bucket tip approaches the boundary L of the set area, the bucket tip speed limit value a calculated by the computing unit 9c increases (| a | decreases. ), This limit value a is the bucket tip speed b by the arm calculated by the calculation unit 9e
When it becomes larger than the component by that is perpendicular to the boundary L, the limit value c = a-by of the boom tip speed due to the boom calculated by the calculation unit 9f becomes a positive value, and the valve command calculation unit 9i
Then, a voltage corresponding to the limit value is output to the proportional solenoid valve 10a on the boom raising side, the pilot pressure of the hydraulic drive unit 50a of the flow control valve 5a is set to the limit value, and the proportional solenoid valve 10b on the boom lowering side is set to a voltage of 0. Is output to set the pilot pressure of the hydraulic drive unit 50b of the flow control valve 5a to zero. This allows
The correction operation by boom raising is performed and the bucket tip speed is corrected by the arm so that the component of the bucket tip speed perpendicular to the boundary L is gradually limited in proportion to the distance D from the bucket tip and the boundary L. With the component bx parallel to the non-boundary L and the speed corrected by the limit value c, the deceleration direction conversion control as shown in FIG. 16 is performed, and the excavation along the boundary L of the set area can be performed.

When the bucket tip extends beyond the boundary L of the set area, the calculation unit 9c determines the bucket tip speed limit value proportional to the distance D from the boundary L between the bucket tip and the set area from the relationship shown in FIG. a is calculated as a positive value, and the limit value c = a-by (> 0) of the bucket tip speed due to the boom calculated by the calculation unit 9f increases in proportion to the limit value a, and the valve command calculation unit 9i The voltage output to the proportional solenoid valve 10a on the boom raising side increases according to the limit value c. As a result, a correction operation is performed by raising the boom so that the bucket tip speed proportional to the distance D is restored outside the set area, and the component bx parallel to the uncorrected boundary L of the bucket tip speed by the arm. With the speed corrected by the limit value c, excavation can be performed while gradually returning along the boundary L of the set area as shown in FIG. Therefore, it is possible to smoothly excavate along the boundary L of the set area simply by clouding the arm.

Further, in the above arm cloud operation, the pilot pressure, which is the command value of the arm operating lever device 4b, is detected by the pressure detector 61a, and the signal is input to the lever signal deceleration control calculation unit 9m to decelerate the lever signal. A target pilot pressure for control is calculated. At this time, when the bucket tip is far from the boundary L of the set region and D ≧ Ya1, the lever signal deceleration control switching calculation unit 9s is not the target pilot pressure calculated by the calculation unit 9m as the arm pilot pressure limit value, The maximum value is output, and the valve command calculator 9k outputs the corresponding voltage to the proportional solenoid valve 11a on the arm cloud side to maximize the opening degree of the proportional solenoid valve 11a. Therefore, the pilot pressure from the operating lever device 4b is directly applied to the hydraulic drive unit 51a on the arm cloud side of the flow control valve 5b, and the arm is operated by the operating lever device 4b.
It is moved to the front as in the operation of b.

When the arm is moved in the forward direction and the tip of the bucket approaches the boundary L of the set area and D <Ya1,
Switching of lever signal deceleration control In the calculation unit 9s, the calculation unit 9
The target pilot pressure for lever signal deceleration control calculated by m is output as a limit value of the arm pilot pressure, and the valve command calculation unit 9k outputs the proportional solenoid valve 11 on the arm cloud side.
A voltage corresponding to the limit value is output to a to limit the pilot pressure of the hydraulic drive unit 51a of the flow control valve 5b to the limit value. Therefore, the arm is decelerated as it approaches the boundary L of the set area. Further, the deceleration amount at this time can be freely adjusted by operating the adjustment buttons 71 to 75 of the deceleration amount adjuster 70.

As described above, according to the present embodiment, when the bucket tip is in the set area, the component of the bucket tip speed perpendicular to the set area boundary L is at the distance D from the bucket tip boundary L. Since it is proportionally limited by the limit value a, positioning of the bucket tip can be easily and smoothly performed during the boom lowering operation, and the bucket tip can be moved along the boundary of the set area during arm cloud operation, thus limiting the area. The excavation can be performed efficiently and smoothly.

Further, when the tip of the bucket is outside the set area, the front device is controlled to return to the set area by the limit value a in proportion to the distance D from the boundary L of the bucket tip. Even at any time, the front device can be moved along the boundary of the set area, and excavation in a limited area can be performed accurately.

Further, at this time, since the speed is previously decelerated by the direction change control as described above, the amount of invasion outside the set area is reduced, and the shock when returning to the set area is greatly reduced. Therefore, it is possible to smoothly perform the excavation in which the area is limited even when the front device is moved quickly, and the excavation in which the area is limited can be smoothly performed.

Further, since the deceleration direction conversion control at the time of operating the arm crowd is speed control, the front device 1A is moved extremely fast, or the operating lever device 4b is abruptly moved.
When the above is operated, the front device 1A may be out of the set area due to a response delay in control such as a delay on the hydraulic circuit or an inertial force applied to the front device 1A.

In this embodiment, the lever signal deceleration control calculation unit 9 performs low-pass filter processing (procedure 14 in FIG. 8).
0) and the lever signal deceleration process (step 160 in FIG. 8), the pilot pressure of the arm operation lever device 4b is reduced according to the distance D between the tip position of the bucket 1c and the boundary of the excavation region, thereby reducing the front device. Even if the speed of 1A is extremely high, abrupt movement of the front device 1A is suppressed as the tip of the bucket 1c approaches the boundary of the set area. Further, even if the operation lever device 4b is suddenly operated within the deceleration area, the arm starts to move smoothly, and the speed after starting to move becomes slow. Therefore, the influence of the response delay in control such as the delay on the hydraulic circuit and the influence of inertia are reduced,
The amount of invasion of the front device 1A outside the set area in the deceleration direction conversion control is greatly reduced, and regardless of the operating speed of the front device 1A or the operating state of the operation lever device, excavation in a limited area can be efficiently and smoothly performed. You can do it.

Also, the required accuracy and speed of excavation vary depending on the work site. Since the excavation accuracy may be somewhat poor, there are cases where it is desired to increase the work speed, and there are cases where accuracy is required even if the speed is extremely slow.

In the present embodiment, by selecting and pressing any of the adjustment buttons 71 to 75 of the deceleration amount adjuster 70 as described above, the reduction amount of the arm pilot pressure by the lever signal deceleration control is freely adjusted. it can. For this reason, it is possible to easily set the optimal reduction amount for every work site, and it is possible to improve work efficiency.

The second embodiment of the present invention will be described with reference to FIGS.
Will be described. In the present embodiment, the present invention is applied to a hydraulic excavator that uses an electric type as an operation lever device.

In FIG. 18, the hydraulic excavator to which the present embodiment is applied is replaced with electric operating lever devices 14a to 14f instead of the hydraulic pilot type operating lever devices 4a to 4f.
14f. The operation lever devices 14a to 14f output a voltage corresponding to the operation amount and the operation direction of the operation lever as an electric signal, and the electric signal is supplied to both ends of the flow control valves 15a to 15f via the control unit A. Electromagnetic drive unit 30 provided with conversion means, for example, a proportional solenoid valve
a, 30b to 35a, 35b, respectively.

The setter 7 and the deceleration amount adjuster 70 are the same as those in the first embodiment.

The control function of the control unit 9A is shown in FIG. The control unit 9A includes a front attitude calculation unit 9a, a region setting calculation unit 9b, and a bucket tip speed limit value calculation unit 9
c, arm cylinder speed calculator 9Ad, arm bucket tip speed calculator 9e, boom boom bucket speed limit value calculator 9f, boom cylinder speed limit value calculator 9g, boom command limit value calculator 9Ah, area Limit control switching calculation unit 9Ar, boom valve command calculation unit 9Ai, lever signal deceleration control calculation unit 9Am, lever signal reduction amount adjustment calculation unit 9An, lever signal deceleration control switching calculation unit 9As, arm valve command calculation unit 9Ak
It has each function of.

The arm cylinder speed calculator 9Ad calculates the arm cylinder displacement by coordinate conversion using the rotation angle of the arm detected by the angle detector 8b, and differentiates it to directly calculate the arm cylinder speed. The arm cylinder speed may be calculated using the operation signal of the arm operation lever device 4b.

The boom command limit calculation unit 9Ah calculates the calculation unit 9g based on the flow rate characteristic of the boom flow rate control valve 15a.
Obtain the boom command value limit value corresponding to the boom cylinder speed limit value obtained in.

In the area limit control switching calculation unit 9Ar, the boom command value is determined according to the limit value of the boom command obtained by the calculation unit 9Ah, the command value of the operation lever device 14a, and the ON / OFF state of the control start switch 7b. And output. The details are shown in the flow chart of FIG.

In FIG. 20, first, in step 400, it is judged whether or not the control start switch 7b is pressed, and if it is pressed, step 410 is proceeded to. In step 410, the limit value of the boom command obtained by the calculation unit 9Ah is compared with the command value of the operation lever device 14a. If the command value is larger than the limit value, the process proceeds to step 420, and the calculation unit 9Ah calculates the arm command value. Output the calculated limit value. On the other hand, step 4
If the control start switch 7bga is not pressed at 00,
Alternatively, when the command value of the operation lever device 14a is smaller than the limit value calculated by the calculation unit 9Ah in step 410, the process proceeds to step 430, and the command value of the operation lever device 14a is output as it is.

Here, in the command value of the operating lever device 14a, as in the XaYa coordinate system, the direction from the outside of the setting area to the inside of the setting area (boom raising direction) is the (+) direction. In addition, the arithmetic unit 9Ar outputs the larger of the boom command limit value and the command value of the operating lever device 14a.
If the bucket tip is within the set area, the limit value c is (-)
Therefore, the smaller absolute value of both is output. Since the limit value c is (+) when the bucket tip is outside the area, the larger absolute value of both is output. Is.

In the boom valve command calculation unit 9Ai, the command value from the calculation unit 9Ar is input, and when the value is positive, the voltage corresponding to the boom raising drive unit 30a of the flow rate control valve 15a is output to output the boom A voltage of 0 is output to the lowering drive unit 30b, which is reversed when the command value is negative.

On the other hand, in the lever signal deceleration control calculation unit 9Am, the operating lever device 4b for the arm of the front device 1A is used.
Lever signal deceleration processing is performed to reduce the operation signal of.

FIG. 21 is a flowchart showing the processing contents of the lever signal deceleration controller 9Am. First, in step 500, the tip position of the bucket 1c in the XY coordinate system obtained by the front attitude calculation unit 9b is converted into a value in the XaYa coordinate system using the conversion data obtained by the region setting calculation unit 9a, and the Y
The distance D between the tip position and the boundary of the setting area in the setting area is obtained from the a coordinate value. Then, in step 510, the distance D to the tip of the bucket 1c as shown in FIG.
And the time constant tg are used to calculate the time constant tg, and the relationship between the distance D and the lever signal deceleration coefficient hg as shown in FIG. 10 is used to calculate the deceleration coefficient hg.

Next, in step 520, the arm operation signal S _{b is} low-pass filtered using the time constant tg to generate the first deceleration operation signal S _b1 , and in step 530 the first deceleration operation signal S _b. The second deceleration operation signal _Sb2 is generated by multiplying _b1 by the deceleration coefficient hg.

Here, the meaning of performing the calculation of the low-pass filter processing performed in step 520 and the low-pass filter processing on the operation signal S _b , and the meaning of further applying the deceleration coefficient hg in step 530 will be described in the first embodiment. It is the same as I did.

Lever signal deceleration control switching calculation unit 9As
Then, the arm command value is switched and output depending on whether or not the tip of the bucket 1c is in the deceleration region, and according to ON / OFF of the control start switch 7b. This detail is shown in FIG.
It is shown in the flow chart.

In FIG. 22, first, in step 600, it is determined whether or not the control start switch 7b is pressed, and if it is pressed, the process proceeds to step 610. In step 610, it is determined whether the tip of the bucket 1c has entered the deceleration area. The storage unit of the control unit 9A stores a distance Ya1 from the boundary L of the set area as shown in FIG. 7 as a value for setting the range of the deceleration area. Step 61
At 0, the procedure 500 of the lever signal deceleration control calculation unit 9Am is performed.
When the distance D obtained in step 1 is smaller than the distance Ya1, it is determined that the vehicle has entered the deceleration area. When it is determined in step 610 that the tip of the bucket 1c has entered the deceleration area, the process proceeds to step 620, and the limit value calculated by the calculator 9Am is output as the arm command value. When the distance D becomes a negative value, the target pilot pressure calculated at D = 0 is continuously output as the limit value of the arm command value. On the other hand, when the control start switch 7bga is not pressed in step 600, or the distance D is larger than the distance Ya1 in step 610, the bucket 1c
If the tip position of does not enter the deceleration area, follow step 63.
The process proceeds to 0 and the command value of the operation lever device 14b is output as it is.

The arm valve command calculation unit 9Ak inputs the arm command value from the calculation unit 9As, and when the command value is positive, outputs a voltage corresponding to the arm cloud drive unit 31a of the flow control valve 15b. , Arm dump drive 3
A voltage of 0 is output to 1b and is reversed when the command value is negative.

Other functions are the same as those in the first embodiment.

In the present embodiment configured as described above, when the operating lever of the boom operating lever device 14a is operated in the boom lowering direction in order to position the bucket tip, the command value of the operating lever device 14a limits the area. It is input to the control switching calculation unit 9Ar. On the other hand, at the same time, the computing unit 9c calculates the bucket tip speed limit value a (<0) proportional to the distance D from the bucket tip and the boundary L between the set areas from the relationship shown in FIG. Bucket tip speed limit value c = a (<0) due to boom
Is calculated, and the boom command limit value calculation unit 9Ah calculates a negative boom command limit value according to the limit value c. At this time, when the bucket tip is far from the boundary L of the set region, the command value of the operation lever device 14a is larger than the boom command limit value obtained by the calculation unit 9Ah, so that the region limit control switching calculation unit 9Ar operates. Since the command value of the lever device 14a is selected and this command value is negative, the valve command calculation unit 9Ai outputs the voltage corresponding to the boom lowering drive unit 30b of the flow rate control valve 15a, and the boom raising drive unit 3A.
A voltage of 0 is output to 0a, which causes the boom to descend according to the command value of the operating lever device 14a.

As described above, as the boom is lowered and the bucket tip approaches the boundary L of the set area, the limit value c = a of the bucket tip speed by the boom calculated by the computing unit 9f.
When (<0) becomes large (| a | or | c | becomes small) and the limit value of the corresponding boom command obtained by the calculation unit 9Ah becomes larger than the command value of the operating lever device 14a, the area limit control is performed. The switching calculation unit 9Ar selects the limit value, and the valve command calculation unit 9Ai gradually limits the voltage output to the boom lowering drive unit 30b of the flow control valve 15a according to the limit value c. As a result, the boom lowering speed is gradually limited as it approaches the boundary L of the setting area, and the boom stops when the tip of the bucket reaches the boundary L of the setting area. Therefore, the bucket tip can be easily and smoothly positioned.

When the bucket tip extends beyond the boundary L of the set area, the calculation unit 9c determines the bucket tip speed limit value proportional to the distance D from the boundary L between the bucket tip and the set area from the relationship shown in FIG. a (= c) is calculated as a positive value, and the valve command calculation unit 9Ai outputs a voltage corresponding to the limit value c to the boom raising drive unit 30a of the flow control valve 15a.
Output to. As a result, the boom is moved in the raising direction so as to restore into the area at a speed proportional to the distance D, and stops when the tip of the bucket returns to the boundary L of the set area. Therefore, the bucket tip can be positioned more smoothly.

When the operation lever of the arm operation lever device 14b is operated in the arm cloud direction in an attempt to excavate in the front direction, an electric signal (described later) output from the valve command calculation unit 9Ak of the control unit 7 is transmitted to the flow control valve. 1
5b is given to the drive unit 31a on the side of the arm cloud, and the arm is moved downward.

On the other hand, at the same time, the operation lever device 14
The command value of b is input to the calculation unit 9Ad to calculate the arm cylinder speed, and the calculation unit 9e calculates the bucket tip speed b by the arm. Further, the calculation unit 9c calculates the bucket tip speed limit value a (<0) proportional to the distance D from the bucket tip and the boundary L between the set areas from the relationship shown in FIG. The speed limit value c = a-by is calculated. At this time, the bucket tip is far from the boundary L of the set area, and a <by (| a |
> | By |), the limit value c is calculated as a negative value, the command value (= 0) of the operating lever device 14a is selected by the switching calculation unit 9Ar of the region restriction control, and the flow rate is calculated by the valve command calculation unit 9Ai. The zero voltage is output to the boom raising drive unit 30a and the boom lowering drive unit 30b of the control valve 15a. As a result, the arm is moved in the front direction according to the electric signal given to the drive unit 31a of the flow rate control valve 15b.

As described above, as the arm is moved toward the front and the bucket tip approaches the boundary L of the set area, the bucket tip speed limit value a calculated by the calculation unit 9c increases (| a | decreases. ), This limit value a is the bucket tip speed b by the arm calculated by the calculation unit 9e
When it becomes larger than the component by perpendicular to the boundary L, the limit value c = a-by of the bucket tip speed due to the boom calculated by the calculation unit 9f becomes a positive value, and the calculation unit 9Ar of the region limit control switching calculates the calculation unit. The limit value calculated in 9A9h is selected, and the valve command calculation unit 9Ai applies a voltage corresponding to the limit value c to the boom raising drive unit 30a of the flow control valve 15a.
Output to. Thus, the correction operation by the boom raising is performed so that the component of the bucket tip speed perpendicular to the boundary L is gradually limited in proportion to the distance D from the bucket tip and the boundary L, and the bucket tip speed of the arm is reduced. The deceleration direction conversion control as shown in FIG. 16 is performed by the uncorrected component bx parallel to the boundary L and the speed corrected by the limit value c, and excavation along the boundary L of the set area can be performed.

When the bucket tip extends beyond the boundary L of the set area, the computing unit 9c determines the bucket tip speed limit value proportional to the distance D from the bucket tip and the boundary L of the set area according to the relationship shown in FIG. a is calculated as a positive value, and the limit value c = a-by (> 0) of the bucket tip speed due to the boom calculated by the calculation unit 9f increases in proportion to the limit value a, and the valve command calculation unit 9Ai The voltage output to the boom raising drive unit 30a of the flow control valve 15a increases according to the limit value c. As a result, a correction operation is performed by raising the boom so that the bucket tip speed proportional to the distance D is restored outside the set area, and the component bx parallel to the uncorrected boundary L of the bucket tip speed by the arm. With the speed corrected by the limit value c, excavation can be performed while gradually returning along the boundary L of the set area as shown in FIG.

In the above arm cloud operation, the command value of the arm operation lever device 14b is input to the lever signal deceleration control calculation unit 9Am and the lever signal deceleration control switching calculation unit 9As of the control unit 9A, and the lever signal deceleration is performed. The deceleration operation signal S _b2 is calculated in the control calculation unit 9Am. At this time, the tip of the bucket is the boundary L of the set area.
When D ≧ Ya1, the switching calculation unit 9As for the lever signal deceleration control uses the calculation unit 9Am as an arm command.
The command value of the arm operating lever device 14b is output instead of the deceleration operation signal _Sb2 calculated in
In Ak, the corresponding voltage is output to the drive unit 31a on the arm cloud side of the flow rate control valve 15b. Therefore, the arm is moved so as to lower in the front direction according to the operation of the operation lever device 14b.

When the arm is moved toward the front, the tip of the bucket approaches the boundary L of the set area, and D <Ya1,
Outputs a deceleration operation signal S _b2 calculated by the switching operation unit 9As In the arithmetic unit 9Am of the lever signal slowdown control, the deceleration operation in the arm-crowding side of the drive unit 31a of the flow control valve 15b in the valve command calculator 9Ak signal S _b2 The voltage corresponding to is output. Therefore, the arm is decelerated as it approaches the boundary L of the set area. Further, the deceleration amount at this time can be freely adjusted by operating the adjustment buttons 71 to 75 of the deceleration amount adjuster 70.

As described above, according to the present embodiment, in the case where the electric lever is adopted as the operation lever device, the same area limiting excavation control as in the first embodiment can be performed.

Further, with respect to the lever signal deceleration control and the lever signal reduction amount adjustment, the same effect as that of the first embodiment can be obtained.

Although some typical embodiments of the present invention have been described above, the present invention is not limited to these and various modifications can be made.

For example, in the above embodiment, both the deceleration process using the deceleration coefficient hg and the low-pass filter process using the time constant tg are performed in the lever signal deceleration control, but only one of them may be performed.

The relationship between the distance between the tip of the bucket and the boundary of the set area and the deceleration vector, the relationship between the time constant tg and the deceleration coefficient hg, and the relationship with the restoration vector are not limited to those set in the above-described embodiment, and various relationships are possible. Can be set.

Further, in the above embodiment, the deceleration amount adjuster 7
No. 0 adjustment button is No. There are 5 types, 1 to 5, but this number can be freely selected. Further, although the push button type is used, the potentiometer may be moved by a rotary dial to make stepless adjustment. In this case A / D
A converter is required. Further, an up / down key may be used. It is also possible to input an arbitrary numerical value with the ten-key unit and to calculate the reduction amount according to the input value from the preset calculation formula.

Further, in the above embodiment, the front device 1
Although the goniometer for detecting the rotation angle is used as the means for detecting the state quantity related to the position and orientation of A, the stroke of the cylinder may be detected.

Although the tip of the bucket has been described as the distance D with respect to the boundary L of the set area for performing the area limited excavation control, the distance from the arm tip pin may be set if it is simply implemented. Also, when setting the area to prevent interference with the front device and ensure safety,
It may be another site where the interference may occur.

Further, the applied hydraulic drive device is a closed center system having a closed center type flow control valve, but it may be an open center system using an open center type flow control valve.

[0126]

According to the present invention, it is possible to efficiently and smoothly excavate a limited area regardless of the operating speed of the front device and the operating state of the operating lever device.

Further, according to the present invention, it is possible to easily adjust the optimal reduction amount of the lever deceleration control for every work site, and it is possible to improve work efficiency.

[Brief description of drawings]

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

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

FIG. 3 is a diagram showing an appearance of a deceleration amount adjuster.

FIG. 4 is a functional block diagram showing a control function of a control unit.

FIG. 5 is a diagram showing a method of setting an excavable area in the area limited excavation control of the present embodiment.

FIG. 6 is a diagram showing a relationship with a distance from a boundary of a set area when obtaining a bucket tip speed limit value.

FIG. 7 is a diagram showing a difference in the bucket tip speed correction operation by the boom when the bucket tip is inside the setting area, on the boundary of the setting area, and outside the setting area.

FIG. 8 is a flowchart showing the processing contents of a lever signal deceleration control calculation unit.

FIG. 9 is a diagram showing the relationship between the time constant and the distance between the tip of the bucket and the boundary of the set area.

FIG. 10 is a diagram showing the relationship between the deceleration coefficient and the distance between the tip of the bucket and the boundary of the set area.

FIG. 11 is a diagram showing changes in lever input due to low-pass filter processing.

FIG. 12 is a diagram showing a cylinder speed characteristic of a flow control valve for an arm.

FIG. 13 is a flowchart showing the processing contents of a lever signal reduction amount adjustment calculation unit.

FIG. 14 is an explanatory diagram of an adjustment calculation of a lever signal decrease amount.

FIG. 15 is a flowchart showing the processing contents of a switching calculation unit for lever signal deceleration control.

FIG. 16 is a diagram showing an example of a correction operation trajectory when the tip of the bucket is within the set area.

FIG. 17 is a diagram showing an example of a correction operation trajectory when the tip of the bucket is outside the set area.

FIG. 18 is a diagram showing a front control device for a construction machine according to a second embodiment of the present invention together with a hydraulic drive device thereof.

FIG. 19 is a diagram showing a control function of a control unit.

FIG. 20 is a flowchart showing the processing contents of a switching calculation unit for area restriction control.

FIG. 21 is a flowchart showing the processing contents of a lever signal deceleration control calculation unit.

FIG. 22 is a flowchart showing the processing contents of a switching calculation unit for lever signal deceleration control.

[Explanation of symbols]

1A front device 1B car body 1a boom 1b arm 1c bucket 2 hydraulic pump 3a boom cylinder 3b arm cylinder 4a-4f; 14a-14f operation lever device 5a-5f; 15a-15f Flow control valve 7 Setting device 7a Area setting switch 7b Control start switch 8a-8c Angle detector 8d tilt angle detector 9 Control unit 9a Front posture calculation unit 9b Area setting calculator 9c Bucket tip speed limit value calculator 9d Arm cylinder speed calculator 9e Arm bucket speed calculator 9f Boom bucket tip speed limit value calculator 9g Boom cylinder speed limit value calculator 9h Boom pilot pressure calculator 9i Valve command calculator 9k valve command calculation unit 9r Area limitation control switching calculation unit 9m lever signal deceleration control calculator 9n Lever signal reduction amount adjustment calculator 9s Lever deceleration control switching calculation unit 10a, 10b proportional solenoid valve 12 Shuttle valve 50a-55b Hydraulic drive unit 61a, 61b Pressure detector 70 Deceleration amount adjuster 71-75 adjustment buttons

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takashi Nakagawa 650 Jinrachicho, Tsuchiura City, Ibaraki Prefecture Tsuchiura Plant, Hitachi Construction Machinery Co., Ltd. (56) Reference JP-A-4-136324 (JP, A) JP-A-2 -173810 (JP, A) International Publication 95/030059 (WO, A1) (58) Fields investigated (Int.Cl. ⁷ , DB name) E02F 3/43 E02F 9/22

Claims (8)

(57) [Claims] 1. A plurality of driven members including a plurality of vertically movable front members constituting an articulated front device, and a plurality of hydraulic actuators respectively driving the plurality of driven members. A plurality of operating means for instructing the operation of the plurality of driven members, and a plurality of hydraulic pressures that are driven according to operation signals of the plurality of operating means and that control the flow rate of the pressure oil supplied to the plurality of hydraulic actuators. And a control valve , wherein the plurality of front members are first front members.
And the second front member, and the first front member is the second flap.
In a region limiting excavation control device for a construction machine, which is rotatably connected to a front end side of a front member, region setting means for setting a movable region of the front device; and a state quantity relating to a position and a posture of the front device. First detecting means for detecting; position / orientation calculating means for calculating the position and orientation of the front device based on a signal from the first detecting means; and the position when the front device approaches a boundary of the setting area. · attitude based on the calculated value of the arithmetic means, said freon
The plurality of operating means within a range in which the speed of the device does not become zero.
A signal deceleration control means for reducing the operation signal of the operating means according to at least the first front member of, when the front device approaches the boundary of the set area, based on the calculated value of the position and attitude calculation means, At least the second operation means of the plurality of operating means is configured so that the front device moves in a direction along the boundary of the setting area and a moving speed is reduced in a direction approaching the boundary of the setting area .
Area limiting excavation control system for a construction machine, characterized by further comprising a deceleration direction change control means to correct the operation signal of the operating means associated to the front member. 2. The area limiting excavation control system for a construction machine according to claim 1, wherein the signal deceleration control means controls the first front member as the distance between the front device and the boundary between the set areas becomes smaller. the first correction computing section area limiting excavation control system for a construction machine characterized by the early days including the decrease amount of the operation signal of the operating means associated to correct the operation signal so as to increase. 3. The area limiting excavation control device for a construction machine according to claim 2, wherein the signal deceleration control means is the first flap.
An area limiting excavation control system for a construction machine, further comprising second correction calculation means for performing low-pass filter processing on an operation signal of an operation means relating to a front member . 4. At least the one of the plurality of operating means
The operation means for the first and second front members is a hydraulic pilot system that outputs pilot pressure as the operation signal, and an operation system including the operation means of the hydraulic pilot system drives a corresponding hydraulic control valve. In the area limitation excavation control device for a construction machine as described above, the signal deceleration control means calculates a target pilot pressure that decreases as a distance between the front device and a boundary between the set regions decreases, and the first front member space limit of the construction machine, wherein the pilot pressure supplied to the hydraulic control valve is a means for correcting an output pilot pressure from the operating means according to the first front member so as to be below the target pilot pressure or related to Excavation control device. 5. The area limiting excavation control system for a construction machine according to claim 4, wherein the operation system is the first front.
The signal deceleration control means includes a pilot line for guiding a pilot pressure to a hydraulic control valve related to a member , and a means for outputting an electric signal corresponding to the target pilot pressure, and a signal installed in the pilot line and driven by the electric signal. An area limiting excavation control system for a construction machine, comprising: 6. The area limiting excavation control system for a construction machine according to claim 1, wherein the first front member is an arm of a hydraulic excavator, and the second front member is a boom of the hydraulic excavator. Area limiting excavation control equipment for construction machinery. 7. A plurality of driven members including a plurality of vertically rotatable front members constituting a multi-joint type front device, and a plurality of hydraulic actuators respectively driving the plurality of driven members. A plurality of operating means for instructing the operation of the plurality of driven members, and a plurality of hydraulic pressures that are driven according to operation signals of the plurality of operating means and that control the flow rate of the pressure oil supplied to the plurality of hydraulic actuators. And a control valve , wherein the plurality of front members are first front members.
And the second front member, and the first front member is the second flap.
In an area limiting excavation control device for a construction machine, which is rotatably connected to a tip of a front member, area setting means for setting a movable area of the front device; and a state quantity related to a position and a posture of the front device. First position detecting means for calculating a position and a posture of the front device based on a signal from the first detecting device; and a position detecting device for calculating a position and a posture of the front device ; and based on the calculated value of the position calculating means, the Freon
Signal deceleration control means for reducing an operation signal of at least one of the plurality of operating means associated with the first front member within a range in which the speed of the operating device does not become zero, and the front device approaches the boundary of the setting area. , The operation signal corrected by the signal deceleration control means and the position /
And based on the calculated value of the position calculating means, the front device moves in the direction along the boundary of the set area, so that the moving speed is reduced in the direction approaching the boundary of the set area
An area limiting excavation control system for a construction machine, comprising: a deceleration direction conversion control means for correcting an operation signal of an operation means related to the second front member . 8. The area limiting excavation control system for a construction machine according to claim 1 or 7 , further comprising a manual operation section operated by an operator, and an operation signal of said signal deceleration control means being operated by operation of this manual operation section. An area limiting excavation control system for a construction machine, further comprising signal reduction amount adjusting means for adjusting a reduction amount.