JP2687169B2 - Slope work control device for construction machinery - Google Patents

Description

TECHNICAL FIELD The present invention relates to a construction machine including a bucket, an arm, and a boom, which is a slope work for keeping a trajectory of a blade edge of a bucket at a predetermined target inclination value. Regarding the control device.

[Prior Art] Generally, a hydraulic excavator is equipped with a boom, an arm, a bucket and hydraulic cylinders for operating them such as a boom cylinder, an arm cylinder, and a bucket cylinder, and these hydraulic cylinders are provided in a driver's seat. The three operating levers are operated separately.

When linearly excavating the slope of the ground with such a hydraulic power shovel, the tip position of the bucket is required to be held so as to move in a predetermined fixed direction. Therefore, the operator must operate the above-mentioned two or three operation levers in a complex and simultaneous manner during the straight line excavation work so that the movement trajectory of the bucket tip becomes a straight line on a desired plane.

However, the operation of manually controlling the depth of the blade edge of the hydraulic power shovel by operating the two or three operation levers in a complex manner requires a great deal of skill. In addition, it takes time to control the excavation direction with high accuracy, which significantly impairs work efficiency.

In view of the above situation, various proposals have been made on conventional techniques for automatically controlling the bucket blade edge depth to a constant value by operating only the arm operation lever.

In all of the conventional techniques, attention is paid to the fact that a certain geometric relationship is established between the rotation angles of the boom, arm, and bucket and the depth of the blade edge of the bucket. Angle is detected, and the bucket edge depth is calculated from these detected rotation angles,
The control is performed so that the calculated cutting edge depth becomes constant.

For example, in Japanese Examined Patent Publication No. 58-36135, "Method of controlling excavation depth in excavator", the deviation between the present value of the bucket blade edge depth and the target value of the blade edge depth is determined, and the deviation is determined. A flow rate command is given to the boom cylinder.

[Problems to be Solved by the Invention] In the related art, the intended purpose that the blade edge depth of a bucket is automatically set to a desired target value simply by operating one arm operation lever is certainly achieved. However, many control systems maintain the depth constant, and there is a problem in finishing the slope to a constant angle, which is one of the important works of the hydraulic power shovel.

In any case, since the control is based on the comparison between the current value of the bucket blade edge position and the target value, the following problems naturally occur together with the characteristics of the hydraulic system.

That is, the hydraulic control system of the working machine of the hydraulic power shovel has a large inertia due to the load and a large response delay. Also, the flow characteristics of the hydraulic operation valve that supplies the pressure oil to each cylinder fluctuates according to the load. Therefore, in the prior art, for example, even if the arm operation lever is operated, the arm does not immediately rotate at a speed corresponding to the operation amount of the lever due to the response delay.

Even if a flow rate command is output to the boom cylinder based on the rotation angle of the arm in such a situation, there is a response delay until the arm rotates with respect to the boom flow rate command, so the arm rotates based on the flow rate command. At that point, the arm has already rotated further, and therefore the bucket blade tip movement locus does not match the target locus.

In addition, for the bucket blade tip movement, the flow rate command according to the deviation between the current position and the target position is given to the boom cylinder, but even if the same flow rate command (boom cylinder speed) is given to the boom cylinder, The rotation angular velocity of the boom that actually occurs differs depending on the rotation angle of the arm and the rotation angle of the boom, and the deviation cannot always be zero. For this reason, in the past, it was necessary to set the control gain for making the above-mentioned deviation zero so that the system would not become unstable regardless of the rotation angle of the arm or boom. Can only be set to a relatively low value. However, this had an influence on the control of the accuracy of the bucket blade locus.

The present invention has been made in view of such circumstances, and improves the delay in control responsiveness and gives an accurate boom command to accurately and stably control the bucket blade locus for slope work. Its purpose is to provide a device capable of doing so.

[Means and Actions for Solving the Problem] A slope work control device for a construction machine according to a first aspect of the present invention is a boom 1 that is rotatably attached to a vehicle body and is rotated by a boom cylinder 4. An arm 2 rotatably attached to the tip of the boom 1 and rotated by an arm cylinder 5; and an arm 2 rotatably attached to the tip of the arm 2 and a bucket cylinder 6. Bucket 3 rotated, boom 1, arm 2, and bucket 3
Angle detecting means 7, 8 and 9 for detecting the respective rotation angles α, β and γ of the robot, the arm operation amount detecting means 12 for detecting the operation amount φ of the arm operating lever 10 for operating the arm 2, or the boom. The boom operation amount detecting means for detecting the operation amount of the boom operation lever for operating 1 and the operation amount φ of either the arm operation amount detecting means 12 or the boom operation amount detecting means when performing slope work. And the output .beta. Or .alpha. Of the arm angle detecting means 8 or the boom angle detecting means 7, the arm cylinder 5 and the boom cylinder 4 are interlocked with each other, and the bucket blade edge D position is in the horizontal versus vertical direction. In the slope work control device for the construction machine, which has a control means for outputting a command for making the change rate Θ0 of the bucket blade constant, the reference position setting means 41 for setting the slope starting point of the bucket blade edge D and the position of the bucket blade edge D are set. Of the slope angle setting means 42 for setting the rate of change Θ0 in the horizontal to vertical direction of the blade and the blade edge position calculation for calculating the current value of the position of the bucket blade edge D based on the outputs β, α of the angle detecting means 8, 7. The bucket blade edge D should pass from the means 29, the first storage means 45 for storing the current value of the position of the bucket blade edge D of the blade edge position calculation means 29, the reference position setting means 41 and the slope inclination angle setting means 42. The target path is calculated, and the horizontal movement distance of the target position of the next bucket blade edge D is calculated from the difference between the current value of the bucket blade edge D stored in the first storage means 45 and the target position, and
Blade locus calculation means 48 for calculating the vertical movement distance, arm operation amount detection means 12, or operation amount φ of any one of boom operation amount detection means, output β of arm angle detection means 8 or boom angle detection. Based on the output α of the means 7, the rate of change Θ0 in the horizontal versus vertical direction of the bucket blade edge D position
Drive command value for the boom cylinder 4 or arm cylinder 5 that keeps the constant Of the first drive command value creating means 26, 27, 28 and the blade tip trajectory calculating means 48 in the horizontal direction, and the set target value of the horizontal movement distance, and the bucket blade tip stored by the first storing means 45. Based on the output value of the present value of D, the deviation between the set target value and the output value of the present value is set to zero, and the set target value Y of the vertical movement distance in the vertical direction next to the cutting edge locus calculation means 48 is set. And a set target value Y based on the output value y1 of the current value of the bucket blade edge D detected by the blade edge position calculating means 29.
The second drive command value creating means 30, 3 for creating the second drive command value 0 of the boom cylinder 4 or the arm cylinder 5 so that the deviation Δy between the current value and the output value y1 of the current value becomes zero.
1,32, each drive command value created by the first drive command value creating means 26,27,28 and the second drive command value creating means 30,31,32. Either the boom control valve 16 for driving the boom cylinder 4 or the arm control valve 13 for driving the arm cylinder 5 is provided according to the sum of zero.

According to the configuration of the first invention, the arm cylinder 5 is controlled according to the operation amount of the arm operation lever 10 to rotate the arm 2, and on the other hand, the first drive command value creating means 26, 27,
Reference numeral 28 denotes the boom cylinder 4 (or arm cylinder 5) so that the rate of change Θ0 in the horizontal versus vertical direction of the bucket blade edge position D is constant with respect to the changing operation amount φ of the arm operation lever 10 (or boom operation lever). Drive command value for driving Create

Further, the second drive command value creating means 30, 31, 32 sets the deviation between the next horizontal movement distance setting target value and the current value of the bucket blade edge D to zero, and sets the next vertical movement distance setting target. The second drive command value 0 for driving the boom cylinder 4 (or the arm cylinder 5) is created so that the deviation Δy between the value Y and the current value y1 of the bucket blade edge D is set to zero. Alternatively, the arm cylinder 5) is drive-controlled according to the sum of the drive command values. That is, the boom cylinder 4 (or the arm cylinder 5) is the first drive command value. Is driven so that the position of the bucket blade edge D moves on the slope in consideration of the predicted change amount of the arm cylinder 5, and the set target value of the next horizontal movement distance of the bucket blade edge D by the second drive command value. And the current value, and the deviation between the vertical movement distance setting target value and the current value are controlled to zero. Therefore, even if the arm 2 is rotated by the arm operation lever 10 with a delayed response, the first drive command value As a result, the boom cylinder 4 is driven in anticipation of this response delay, and the second drive command value 0 controls the boom cylinder 4 to reach the set target value for the next movement distance of the bucket blade tip D. It will move systematically on the set slope.

The slope work control device for a construction machine according to the second invention of the present application, in the first invention, is the operation amount φ of the arm operation lever 10.
Corresponding to the arm cylinder estimated speed calculation means 26 for calculating the estimated speed VA of the arm cylinder 5 and the output β of the arm angle detection means 8, based on the estimated speed VA of the arm cylinder 5 and the arm angle β. , Arm rotation angular velocity Arm rotation angular velocity calculation means 27 for calculating And a boom speed calculation means 28 that creates a drive command value for the boom cylinder 4 that keeps the rate of change Θ0 in the horizontal to vertical direction of the bucket blade edge D position constant based on the output α of the boom angle detection means 7. 1 drive command value creating means 26, 2
7,28, the sum of the respective drive command values created by the first drive command value creating means 26,27,28 and the second drive command value creating means 30,31,32, and the rotation angle α of the boom. The boom link correction means 34 for calculating the estimated speed VB of the boom cylinder 4 in accordance with
The boom control valve 16 is driven by the estimated speed VB of the boom cylinder 4 calculated by the boom link correction means 34.

According to the configuration of the second invention, the following operation is provided in addition to the operation of the first invention.

The arm rotation angular velocity can take different values depending on the rotation angle β of the arm 2 and the velocity of the arm cylinder 5,
Also, attention is paid to the fact that the boom rotation angular velocity can take different values depending on the boom rotation angle α and the speed of the boom cylinder 4. That is, the arm rotation angular velocity calculation means 27
Based on the estimated speed VA of the arm cylinder 5 corresponding to the operation amount φ of the arm operation lever 10 and the arm rotation angle β, the accurate arm rotation angular velocity is obtained. Is calculated. The boom speed calculation means 28 uses this arm rotation angular velocity. A first drive command value for the boom cylinder 4 that accurately moves on the slope where the bucket blade tip D position is set is created based on the link mechanism including the boom 1, the arm 2, and the bucket 3. Further, the boom link correcting means 34 includes a sum of the respective drive command values created by the first drive command value creating means 26, 27, 28 and the second drive command value creating means 30, 31, 32 and the boom. Since the boom control valve 16 is driven by the estimated speed VB of the boom cylinder 4 calculated according to the rotation angle α, the boom 1 can accurately move at a substantially constant speed on the slope where the bucket blade tip position D is set. Rotated to move.

In this way, the first drive command value created by the boom speed calculation means 28 And the estimated speed VB of the boom cylinder 4 calculated by the boom link correction means 34, the boom 1 is rotated so as to accurately move at a substantially constant speed on the slope where the bucket blade edge position D is set. It

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a block diagram of an embodiment of a slope work control apparatus according to the present invention, FIG. 2 is a graph for explaining arithmetic processing of each circuit in the embodiment, and FIG. 3 is an overall configuration of the embodiment. 4 shows the construction of the working machine of the hydraulic power shovel in the embodiment, and FIG. 5 shows the geometrical relationship of the working machine shown in FIG.

As shown in FIG. 4, the working machine (front attachment) of the hydraulic power shovel PS is provided with the boom 1, the arm 2 and the bucket 3, and the respective rotation fulcrums thereof.
A boom angle detector 7, an arm angle detector 8, and a bucket angle detector 9 that detect the rotation angles α, β, and γ (see FIG. 5) of O, B, and C are respectively provided. . As the detectors 7, 8 and 9, for example, potentiometers are used.

In FIG. 5, the Y axis is a vertical line passing through the fulcrum O, l ₁ is the length of the line segment OB connecting the fulcrums O and B, l ₂ is the length of the line segment BC connecting the fulcrums B and C, and l ₃ is A length of a line segment CD connecting the fulcrum C and the bucket tip point D, and L ₂ is a length of a line segment BD connecting the fulcrum B and the bucket tip point D (hereinafter, referred to as arm blade tip total length).

At this time, the rotation angle α is the rotation angle of the line segment OB with respect to the Y axis,
The rotation angle β is the rotation angle of the line segment BC with respect to the extension line of the line segment OB, and the rotation angle γ is the line segment with respect to the extension line of the line segment BC.
Indicates the rotation angle of the CD. Further, β ₀ represents an angle formed by the line segment BD with respect to the extension line of the line segment OB (hereinafter, referred to as arm edge angle).

Between the above L ₂ , l ₂ , l ₃ and γ, as is clear from FIG. 5, L ₂ = (l ₂ ² −l ₃ ² −2l ₂ l ₃ cos γ) ^1/2 ……… The mathematical relationship (1) holds.

Here, since l ₂ and l ₃ are known, if the rotation angle γ is detected by the detector 9, the arm blade tip total length L ₂ can be obtained by substituting the detected value into the expression (1). It will be possible.

Further, between the above-mentioned β ₀ , β, l ₃ , γ and L ₂ , as is apparent from FIG. 5, β ₀ = β = sin ⁻¹ (l ₃ sin γ / L ₂ ) ... ( The geometrical relationship 2) is established.

Here, l ₃ is known, and L ₂ is obtained by the above formula (1). Therefore, when each of the rotation angles β and γ is detected by the detectors 8 and 9, these detected values are calculated as the second (2) By substituting into the equation, it becomes possible to obtain the arm edge angle β ₀ .

The rotation angle signals indicating the respective rotation angles α, β and γ detected by the rotation angle detectors 7, 8 and 9 are added to the CPU 22 of the controller 20 via the input interface 21 of the controller 20 shown in FIG. To be

The boom 1, the arm 2, and the bucket 3 are rotated by a boom cylinder 4, an arm cylinder 5, and a bucket cylinder 6, respectively.

At the driver's seat of the hydraulic power shovel PS, a boom operation lever (not shown) for rotating the boom 1, the arm 2 and the bucket 3, a arm operation lever 10 and a bucket operation lever 11 are provided ( (See FIG. 1).

And the arm operation lever 10 is
An arm operation lever angle detector 12 for detecting the operation amount of 10, that is, the operation angle of the arm operation lever 10 is additionally provided.
As the detector 12, for example, a potentiometer is used. The operating angle detected by the detector 12 is also
Similar to the above rotation angles α, β and γ, the CPU 22 of the controller 20 via the input interface 21 of the controller 20
Is added to

When the operation levers 10 and 11 are operated, the spools of the arm operation valve 13 and the bucket operation valve 14 are moved according to the respective operation amounts, and the speeds corresponding to the respective operation amounts are moved by the operation valves 13 and 14. Arm cylinder 5 and bucket cylinder 6
Are expanded or contracted, respectively. That is, as a result of this expansion / contraction operation, the rotation angles β and γ of the arm 2 and the bucket 3 respectively change, and the tip position D of the bucket 3 changes in accordance with this change.
Therefore, the horizontal component x and the vertical component y of the are changed.

On the other hand, an operation panel 40 is provided in the driver's seat of the hydraulic excavator PS. The operation panel 40 includes a reference position setting device switch 41, a slope inclination angle setting device 42, and an automatic mode switch 43 described later.

The automatic mode switch 43 is a switch for selecting whether the boom cylinder 4 is extended or retracted manually or automatically. If the switch 43 is not pushed,
That is, when the boom 1 is rotated by a manual operation of the operator, the “manual” signal of the automatic mode switch 43 is input to the CPU 22 via the input interface 21. As a result, the CPU 22 makes a "manual" determination and switches the manual automatic switching valve 15 of the hydraulic system of the boom cylinder 4 to the manual side via the driver 23.

In this case, when the boom operation lever (not shown) is manually operated, the spool of a boom operation valve (not shown) similar to the arm operation valve 13 and the bucket operation valve 14 is moved according to the operation amount, The boom operation valve controls the boom cylinder 4 at a speed determined by the flow rate of pressure oil according to the operation amount.
Is expanded or contracted. That is, as a result of this retracting operation, the rotation angle α of the boom 1 changes, and the horizontal component x and the vertical component y of the tip position D of the bucket 3 change according to this change.

Therefore, as an operator, when the automatic mode switch 43 of the operation panel 40 is operated to the "manual" side, the boom operation lever (not shown), the arm operation lever 10 and the bucket operation lever 11 are operated in combination. Thus, it is possible to perform desired excavation while moving the horizontal component x and the vertical component y of the tip position D of the bucket 3, that is, the bucket blade edge positions x, y to desired positions.

On the other hand, when the automatic mode switch 43 is pushed, that is, when the automatic mode switch 43 is operated to the “manual” side, the “automatic” signal of the automatic mode switch 43 is input to the CPU 22 via the input interface 21. . As a result, C
The PU 22 makes a determination of "automatic" and switches the manual automatic switching valve 15 of the hydraulic system of the boom cylinder 4 to the automatic side via the driver 23.

In this case, the boom cylinder 4 is expanded and contracted by the boom control valve (electromagnetic proportional control valve) 16 regardless of the operation of the boom operation lever.

When the work is started, the bucket blade edge is positioned at a reference position of a predetermined finishing surface by the manual operation, for example, at the uppermost part of the slope, and the reference position setting switch 42 is pushed to cause a switch closing signal to be transmitted to the CP via the input interface circuit 21.
Input to U22. Further, the slope angle setting device 43 sets a target slope angle θ ₀ . This target slope inclination angle θ ₀
Is input to the CPU 22 via the input interface circuit 21.

When setting the reference position in the above description, the following arithmetic processing is performed.

Before starting the work, the blade tip of the power shovel work machine is moved to a predetermined position and the following calculation is performed by pressing the reference position setting switch 42, the blade tip position at that time calculated by the blade tip position calculation circuit 29, that is, the method. Reference positions x ₀ and y ₀ for surface finishing are set and recorded in the storage circuit 45.

The following calculation is performed in the above-mentioned blade edge position calculation circuit 29.

The blade edge position at that time is measured values α, β and γ from the boom angle detector 7, the arm angle detector 8 and the bucket angle detector 9, and the length l _{1 of the} boom recorded in advance, From the arm length l ₂ and the bucket length l _3, coordinate values X ₀ and Y ₀ with the boom attachment position O as an intersection can be calculated by the following formula.

X ₀ = l ₁ · cos α + l ₂ · cos (α + β) + l ₃ · cos (α + β
+ Γ) ……… (6x) Y ₀ ＝ l ₁ · sin α ＋ l ₂ · sin (α + β) ＋ l ₃ · sin (α + β
+ Γ) ……… (6y) (See Fig. 5) Target slope angle θ ₀ set by slope angle setter 43
Is inputted to the inclination angle change rate calculation circuit 46 to calculate and calculate the change rate Θ ₀ of the horizontal distance to the vertical distance and recorded in the storage circuit 47.

When the automatic mode switch 43 is operated to the "automatic" side, the output of the arm operation amount detector 12, the outputs α, β and γ of the angle detectors 7, 8 and 9 and the above-mentioned respective Based on the values x ₀ , y ₀ , Θ ₀ obtained as a result of the setting process, the controller 20 performs the arithmetic process described later,
Based on this arithmetic processing, an operation command signal i for making the locus of the blade edge position of the bucket 3 pass the set values x ₀ , y ₀ , Θ ₀ is created and applied to the solenoid of the boom control valve 16. .

In this case, as the operator, the arm operation lever 10
A desired excavation work for maintaining the blade edge locus of the bucket 3 constant can be performed only by operating only.

Next, with reference mainly to FIG. 1 and FIG. 2, the processing performed by the controller 20 when the automatic mode switch 43 is operated to the “automatic” side will be described.

In the embodiment, the bucket operation lever 11 is in the neutral state.

In the arm blade total length calculation circuit 24 shown in FIG. 1, the current arm blade total length L ₂ is calculated from the equation (1) based on the current rotation angle γ of the bucket 3 output from the bucket angle detector 9. Processing is performed. Since the bucket operation lever 11 is in the neutral state and γ is a constant value, the total length L ₂
Is a constant value.

On the other hand, in the arm edge angle calculation circuit 25, based on the current rotation angles β and γ of the arm 2 and the bucket 3 output from the arm angle detector 8 and the bucket angle detector 9, respectively, the present expression (2) is used. A process for calculating the arm edge angle β ₀ is performed. Here, since the total length L ₂ and the rotation angle are constant values, the second term on the right side of the equation (2) is a constant value. Therefore, the arm blade edge angle β ₀ is a value obtained by adding a constant value to the rotation angle β of the second arm at present.

Therefore, the outputs L ₂ and β ₀ of the arm blade edge total length calculation circuit 24 and the arm blade edge angle calculation circuit 25 are the arm operation lever 1
It is uniquely determined only by the operation of 0 (only the arm rotation angle β).

On the other hand, the current lever operation angle is detected by the arm operation amount detector 12 according to the operation of the arm operation lever 10, and the arm cylinder estimated speed calculation circuit 26 calculates the arm cylinder estimated speed VA corresponding to the detected value by the following formula (3). The estimated speed VA is output to the arm link correction circuit 27.

Here, the arm cylinder estimated speed VA is the speed of the arm cylinder 5 that will eventually be reached if the arm operating lever 10 is currently operated to the lever angle. Furthermore, when the arm operating lever 10 is quickly operated to a predetermined lever angle, the speed of the arm cylinder 5 does not reach VA immediately. After a short time delay, the speed reaches VA. This delay is caused by the characteristics of the hydraulic system. In this arithmetic circuit 26, the arm cylinder estimated speed VA according to the present lever angle is calculated by the following equation (3).
It will be output in the correspondence relationship shown in the formula.

VA = f ₁ () (3) (See FIG. 2 (a)) Here, the function f ₁ is a function that is uniquely determined by the hydraulic system of the arm cylinder 5, and is shown in FIG. 2 (a). It has the characteristics shown in.

Next, in the arm link correction circuit 27, the arm cylinder estimated speed VA output from the arm cylinder estimated speed calculation circuit 26 and the current detected value β of the arm angle detector 8
Based on, the rotation angular velocity of the arm 2 corresponding to the rotation angle β and the estimated velocity VA The arithmetic expression Rotation angular velocity obtained by Is added to the boom speed calculation circuit 28.

Function f ₂ in equation (4) is a function uniquely determined by the link structure of the arm 2 has a characteristic as shown in FIG. 2 (b).

And the above rotational angular velocity Is the rotational angular velocity of the arm 2 when the arm cylinder 5 is operating at the estimated velocity VA and the arm rotational angle is β.

Next, in the boom speed calculation circuit 28, the arm rotation angular velocity output from the arm link correction circuit 27 is used. And the arm blade tip total length L ₂ output from the arm blade tip total length calculation circuit 24, the arm blade tip angle β ₀ output from the arm blade tip angle calculation circuit 25, and the current rotation angle α of the boom 1 output from the boom angle detector 7. Based on the arm rotation angular velocity Angular velocity of boom 1 corresponding to Is Is calculated, and the calculated rotational angular velocity is calculated. Is output to the addition circuit 33 described later.

The arm cylinder estimated speed calculation circuit 26, the arm link correction circuit 27, and the boom speed calculation circuit 28 described above constitute a first drive command value creating means. Here is the rotational angular velocity Means that the arm 2 has a rotational angular velocity It is the rotational angular velocity of the boom 1 required to pass the commanded blade edge position x, y of the bucket 3 (position that satisfies x ₀ , y ₀ , Θ ₀ ; the same applies below) that changes when the bucket 3 rotates.
Furthermore, the arm 2 has a rotational angular velocity And the boom 1 rotates If the bucket 3 rotates, the blade edge position of the bucket 3 passes through x and y.

After all, from the boom speed calculation circuit 28, the rotational angular speed of the boom 1 required to pass the blade edge command positions x and y of the bucket 3 when the arm operation lever 10 is constantly operated with a lever angle. Is output.

On the other hand, in the blade edge position calculation circuit 29, the boom angle detector 7
Based on the current rotation angle α of the boom 1, the output L ₂ of the arm blade edge total length calculation circuit 24, and the output β ₀ of the arm blade edge angle calculation circuit 25, which are detected by the current value x ₁ , y ₁ of the blade tip position of the bucket 3. However, as described above, it is calculated by the following equation x ₁ = l ₁ sin α + L ₂ sin (α + β ₀ ) ………… (6x) y ₁ ＝ l ₁ cos α−L ₂ cos (α + β ₀ ) ………… (6y) , X ₁ and y ₁ of the calculation result are input to the cutting edge axis trace calculation circuit 48.

On the other hand, when the reference position setting switch 41 is pushed, the reference positions x ₀ and y ₀ recorded in the first memory circuit 45 and the slope inclination angle setting device.
Θ ₀ set in 42 and calculated in the change rate calculation circuit 46 (not shown) and recorded in the storage circuit 47 is the cutting edge locus calculation circuit 4
Entered in 8.

In the cutting edge locus calculation circuit 48, the following calculation is performed based on each of the above-mentioned input values, and the excavation target vertical depth of the cutting edge D (at the horizontal target position x obtained by adding a predetermined distance to the position x ₀ of the current horizontal component). Calculate Y.

Y = Θ ₀ · (x ₁ −x) + y ₀ (6) The predetermined distance in the above description means the controllability and response speed determined by the function / performance of the power shovel and the required slope. It is a value determined from the finishing accuracy, and normally x ₀ may be used as it is instead of X.

The vertical component y ₁ of the current position of the blade edge of the bucket 3 calculated by the blade edge position calculation circuit 29 and the excavation target vertical depth Y of the above calculation result are input to the comparison circuit 30, and the deviation Δy is calculated as Δy = Y −y ₁ ……… (7) The calculated deviation Δy is calculated by the coordinate conversion circuit.
Output to 31.

Next, in the coordinate conversion circuit 31, the deviation Δy input from the comparison circuit 30, the output L ₂ of the arm blade edge length calculation circuit 24, the output β _{0 of the} arm blade angle calculation circuit 25, and the boom angle angle detector 7 are detected. Based on the current rotation angle α of the boom 1, the angular deviation Δα of the boom 1 corresponding to the deviation Δy is calculated by the calculation formula Δα = Δy / [l ₁ sin α + L ₂ sin (α + β ₀ )] (8) , The obtained angle deviation Δα is added to the proportional gain multiplication circuit 32.

Here, the angle deviation Δα means that the deviation Δy is zero, that is, from the current rotation angle α of the boom 1 required to bring the current positions x ₁ and y ₁ of the blade tip positions of the bucket 3 to the target values X and Y. Is the amount of change in angle. Furthermore, the rotation angle α of the boom 1
By changing the angle deviation amount Δα, the blade edge position of the bucket 3 reaches the target values X and Y from the current values x ₁ and y ₁ .

Next, in the proportional gain multiplication circuit 32, the rotational angular velocity 0 of the boom 1 corresponding to the angular deviation Δα output from the coordinate conversion circuit 31 is obtained by the arithmetic expression 0 = KΔα ... (9), and the obtained rotational angular velocity is obtained. 0 adder circuit 33
Perform processing to add to. In the equation (9), K is a proportional gain.

The above-mentioned comparison circuit 30, coordinate conversion circuit 31, and proportional gain multiplication circuit 32 constitute a second drive command value creating means.
In the adder circuit 33, the rotational angular velocity output from the boom speed calculation circuit 28 And the rotational angular velocity command value for the boom 1 based on the rotational angular velocity 0 output from the proportional gain multiplication circuit 32 The calculated angular velocity command value is added to the boom link correction circuit 34.

Next, in the boom link correction circuit 34, the rotation angular velocity command value output from the addition circuit 33 and the current rotation angle α of the boom 1 detected by the boom angular velocity detector 7 are detected.
Based on and, the flow rate command value for the boom cylinder 4 corresponding to the rotation angle α and the rotation angular velocity command value.
V _B , that is, the speed command value of the boom cylinder 4, is calculated by the calculation formula V _B = / f ₃ (α) (11) (see FIG. 2 (c)), and the calculated flow rate command value V _B Is added to the control amplifier 35.

Function f ₃ wherein in (11) is a function uniquely determined by the link structure of the boom 1 in the same manner as the function f _2, and has a characteristic as shown in FIG. 2 (c) . The flow rate command value V _B is the operating speed of the boom cylinder 4 when the boom 1 is operating at the rotational angular velocity and the boom rotational angle is α. Conversely, if the rotation angle of the boom cylinder 4 is not operating at a speed V _B boom 1 is α, the boom 1 will be rotated with the rotational angular velocity.

Next, the control amplifier 35 converts the flow rate command value V _B output from the boom link correction circuit 34 into a predetermined drive current i for applying to the solenoid of the boom control valve 16, and the drive conversion current i is converted into the solenoid. Add to.

As a result, the boom control valve 16 is the drive current i, i.e. extending and retracting operation of the boom cylinder 4 at a speed corresponding to the flow rate command value V _B. Then, the horizontal position X of the blade edge of the bucket 3
The depth at will coincide with the output value Y of the blade locus calculation circuit 48.

As described above, according to the embodiment, the arm operation lever
When 10 is operated to a predetermined operation angle, the arm cylinder 5 is expanded and contracted via the arm operation valve 13, and the arm 2 is rotated. At the same time, the blade edge position of the bucket 3 is secured according to the operation angle of the arm operation lever 10. That is, the rotational angular velocity of the boom 1 for making the deviation of the blade edge position zero Predict. Then, on the other hand, the rotational angular velocity 0 of the boom 1 required to make the deviation Δy between the current values x ₁ and y ₁ of the blade tip positions of the bucket 3 and Y from the target value X zero is calculated. Then, the rotational angular velocity predicted based on the operation amount of the arm operation lever 10 And a flow rate command value corresponding to the rotational angular velocity obtained by adding the rotational angular velocity 0 corresponding to the deviation Δy of the blade tip position of the bucket 3 to the boom cylinder 4.

Here, conventionally, the flow rate command value according to the deviation between the current value of the blade tip position of the bucket 3 and the target value is simply given to the boom cylinder 4. In this case, when the arm operating lever 10 is operated, the arm 2 rotates with a response delay. Then, while the arm 2 is rotating, on the one hand, the flow rate command value according to the above deviation is given to the boom cylinder 4 to rotate the boom 1, but the boom rotates in response to the flow rate command of the boom. Since there is a response delay before the rotation, the rotation angle of the arm 2 has already reached a different rotation angle when the boom 1 rotates according to the flow rate command value. Therefore, it is extremely difficult to make the deviation zero. It was difficult. In particular, when the arm operating lever 10 is rapidly operated, the accuracy of controlling the blade locus is further deteriorated. However, according to the embodiment, the arm operating lever 10
Is operated, the rotational angular velocity of the boom 1 for securing the blade edge position of the bucket 3 is estimated according to the operation amount, and the flow rate command value corresponding to this is estimated as the flow rate command value according to the deviation of the blade edge position. I try to take it into consideration. Therefore, it is possible to improve the deterioration of the accuracy of the control of the cutting edge position due to the response delay.

Further, in the embodiment, in the arm link correction circuit 27, the accurate rotational angular velocity of the arm 2 according to the estimated velocity VA of the arm cylinder 4 and the rotational angle β of the arm 2 is obtained. Is calculated. In the boom speed calculation circuit 28, the accurate rotational angular speed of the arm 2 is calculated. Angular velocity of the boom 1 required to secure the blade edge position of the bucket 3 according to the target Will be obtained accurately.

Then, in the boom link correction circuit 34, the rotational angular velocity of the boom 1 required to make the deviation from the target blade edge position of the bucket 3 zero. Boom 1 required to reduce the deviation between the current value and the target position 1
An accurate flow rate command value V _{B of} the boom is calculated in accordance with the rotation angular velocity command value of the boom 1 and the rotation angle α of the boom 1 that is obtained by adding the rotation angular velocity of 0.

Therefore, in the prior art, since the deviation Δy of the bucket blade tip position is used as the flow rate command value to be given to the boom cylinder as it is, the bucket blade tip positions X and Y may be set depending on the values of the rotation angles α and β of the boom 1 and the arm 2. Although it was not possible to exactly match them, according to the embodiment, an accurate flow rate command value V _B corresponding to the rotation angles α and β is calculated, and the boom cylinder 4 is calculated according to the accurate flow rate command value V _B. Will be activated. Therefore, the bucket blade tip positions x and y are
Matches X and Y.

In addition, in the embodiment, an example in which the present invention is applied to a working machine including three elements of a boom, an arm, and a bucket has been described, but the present invention is not limited to this, and for example, a two-stage boom can be used. It goes without saying that the present invention can also be applied to a working machine that the user has.

Further, in the embodiment, an example in which the present invention is applied to a hydraulic power shovel has been described, but the present invention is not limited to this, for example, a construction machine that performs work by holding the blade edge position of a bucket such as a backhoe on a certain path. If so, the application and implementation are naturally possible.

It was explained that when setting the reference position, the blade position of the power shovel was operated and set to a predetermined position and the reference position setting switch was pressed, but the reference position setting switch is a position where the slope passes as a digital switch capable of inputting digital numerical values. The horizontal and vertical coordinate values based on the boom mounting position O of the power shovel may be directly input. In that case, it is necessary to add a calculation function to the internal circuit of the reference position setting switch to coordinate shift the set reference position to the boom attachment position O point of the power shovel.

It is also possible to record not the angle but the change rate of the horizontal distance to the vertical distance, that is, the tangent value of the slope angle of inclination in the standard display in the standard slope inclination setting device. In that case, the above-described inclination angle change rate calculation circuit 46 is unnecessary.

In addition, a table for designating a target tilt angle by a geometric calculation circuit is created from the reference position setting switch and the slope inclination angle setting device, and is compared with the output of the blade edge position calculation circuit 29, that is, the current value of the bucket blade edge. However, an arbitrary work finish surface can be automatically and accurately completed by creating a table for designating an appropriate work trajectory in advance on the drawing and recording it in the slope inclination setting device.

If the work locus is created on the table, the locus does not necessarily have to be a straight line and can be finished into an arbitrary curve.

[Effects of the Invention] As described above, according to the present invention, the blade edge position of the bucket is controlled based on the deviation including not only the current value and the target value of the bucket blade edge position but also the predicted change amount of the arm. Therefore, the control response is improved. Further, the boom is rotated by an optimum command corresponding to the rotation angle of the boom and the arm. As a result, the blade edge position of the bucket can be accurately and stably matched with the desired target value, and the working speed can be improved and the work can be accurately and stably performed.

[Brief description of the drawings]

FIG. 1 is a control block diagram showing an embodiment of a slope work control apparatus for a construction machine according to the present invention. 2 (a), (b) and (c) are used to explain the calculation processing performed by the boom cylinder estimated speed calculation circuit, arm link correction circuit, and boom link correction circuit shown in FIG. 1, respectively. Graph chart. FIG. 3 is a block diagram conceptually showing the overall structure of the embodiment. FIG. 4 is a side view showing the configuration of the working machine of the hydraulic power shovel in the embodiment. FIG. 5 is a graph showing the geometrical relationship of the working machine shown in FIG. PS ... hydraulic power shovel, 1 ... boom, 2 ... arm, 3 ... bucket, 4 ... boom cylinder, 5 ... arm cylinder, 6 ... bucket cylinder, 7 ... boom angle detector, 8 ... … Arm angle detector, 9 …… Bucket angle detector, 10 …… Arm operation lever, 11 …… Bucket operation lever, 12 …… Arm operation amount angle detector, 13 …… Arm control valve, 14 …… Bucket operation Valve, 15 ... Manual automatic switching valve 16 ... Boom control valve (electromagnetic proportional control valve), 20 ... Controller, 21 ... Input interface 22 ... CPU 23 ... Driver 24 ... Arm blade edge length calculation circuit, 25 ...... Arm edge angle calculation circuit, 26 …… Arm cylinder estimated speed calculation circuit, 27 ・ ・ ・
… Arm link correction circuit, 28 …… Boom speed calculation circuit,
29 …… Blade edge position calculation circuit, 30 …… Comparison circuit, 31 …… Coordinate conversion circuit, 32 …… Proportional gain multiplication circuit, 33 …… Addition circuit, 34 …… Boom link correction circuit, 40 …… Operation panel 41… ... reference position setting switch, 42 ... slope inclination setting device, 43 ... automatic mode switch, 45, 47 ... first memory circuit, second memory circuit, 46 ... tilt angle change rate calculation circuit, 48
...... Cutting edge trajectory calculation circuit,

Claims (2)

(57) [Claims] 1. A boom which is rotatably attached to a vehicle body and which is rotated by a boom cylinder, and an arm which is rotatably attached to the tip of the boom and is rotated by an arm cylinder. And a bucket that is rotatably attached to the tip of the arm and that is rotated by a bucket cylinder, angle detectors that detect the rotation angles of the boom, the arm, and the bucket, and the arm is operated. Arm operation amount detection means for detecting the operation amount of the arm operation lever or boom operation amount detection means for detecting the operation amount of the boom operation lever for operating the boom, and the arm operation amount when performing slope work. Detection means, or
Based on the operation amount of any one of the boom operation amount detection means and the output of the arm angle detection means or the output of the boom angle detection means, the arm cylinder and the boom cylinder are interlocked to control the horizontal position of the bucket blade edge. In a slope work control device for a construction machine, which has a control means for outputting a command for making a change rate in the vertical direction constant, a reference position setting means for setting a slope starting point of a bucket blade edge, and a horizontal position of the bucket blade edge. The slope inclination angle setting means for setting the rate of change in the vertical direction, the blade edge position calculating means for calculating the current value of the position of the bucket blade edge based on the output of each angle detecting means, and the bucket blade edge of the blade edge position calculating means. The first storage means for storing the current value of the position, the reference position setting means, and the slope inclination angle setting means calculate a target path through which the bucket blade edge should pass. A blade edge locus calculation means for calculating a horizontal movement distance and a vertical movement distance of a next bucket blade tip target position from the difference between the current value of the bucket blade tip stored in the first storage means and the target position, and arm operation amount detection Means or the operation amount of any one of the boom operation amount detecting means, and the output of the arm angle detecting means or the output of the boom angle detecting means, the rate of change of the bucket blade edge position in the horizontal versus vertical direction is made constant. A first drive command value creating means for creating a first drive command value for the boom cylinder or the arm cylinder, a horizontal movement distance set target value in the horizontal direction next to the cutting edge locus calculation means, and a first storage. Based on the output value of the present value of the bucket blade tip stored by the means, the deviation between the set target value and the output value of the present value is set to zero, and the next trajectory of the blade locus calculation means is set. Direction, based on the set target value of the vertical movement distance and the output value of the current value of the bucket blade edge detected by the blade edge position calculating means, the deviation between the set target value and the output value of the current value is set to zero. To
Second drive command value creating means for creating a second drive command value for the boom cylinder or arm cylinder, and each drive command created by the first drive command value creating means and the second drive command value creating means. A slope work control device for a construction machine, comprising a boom control valve for driving a boom cylinder or an arm control valve for driving an arm cylinder according to a sum of values. 2. The arm cylinder estimation according to claim 1, based on an output of an arm cylinder estimated speed calculation means for calculating an estimated speed of the arm cylinder corresponding to an operation amount of the arm operation lever, and an output of the arm angle detection means. Based on the output of the arm rotation angular velocity calculation means and the arm rotation angular velocity calculation means for calculating the arm rotation angular velocity based on the speed and the arm angle, the rate of change of the bucket blade edge position in the horizontal versus vertical direction is constant. And a boom speed calculation means for creating a drive command value for the boom cylinder.
Of the boom cylinder according to the sum of the drive command values created by the drive command value creating means, the first drive command value creating means, and the second drive command value creating means and the rotation angle of the boom. A slope work control apparatus for a construction machine, comprising: a boom link correcting means for calculating a speed and a boom control valve driven by an estimated speed of a boom cylinder calculated by the boom link correcting means.