JPS5833650A - Controller for excavation by oil-pressure shovel - Google Patents

Abstract

PURPOSE:To automatically perform horizontal excavation through the operation of a bucket as well as to increase the length of the horizontal excavation by the calculation of a target boom angle from the detected values of boom and bucket angles. CONSTITUTION:A boom 2 is pivotally supported in an inclinable manner by a boom cylinder 5 on the body 1, an arm 3 is pivotally supported in a rocking manner by an arm cylinder 6 at the tip of the boom 2, and a bucket 4 is pivotally supported in a turnable manner by a bucket cylinder 7 at the tip of the arm 3. Boom angle alpha and bucket angle gamma are detected by detectors 9 and 10, the bucket angle gamma is differentiated by a differentiator 11, the bucket angle gamma and the boom angle alpha are put in a functional generator 14, its output is put in a multiplier 15, bucket angular speed gamma is also put in the amplifier 15 to obtain a target boom angular speed alpha' and by this a target boom cylinder speed y'alpha is obtained. By the output, the boom cylinder 5 is controlled and horizontal excavation is automatically made through the operation of the bucket 4.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an excavation control device for a hydraulic excavator.

Loading Hydraulic shovel 1. Normally, the excavator body is advanced to the ground of the excavation tube to perform the next excavation. In this case, if excavated soil, rocks, etc. are present in the forward direction of the shovel body, the shovel body will tilt and the excavation work will be hindered. For this reason, it is necessary to excavate the ground flat in the forward direction of the hydraulic excavator.

Figure 1 is a diagram showing the front 1 section of a loading hydraulic excavator.A boom 2 is pivoted to the excavator body 1 so that it can be moved up and down by a boom cylinder 5, and an arm 3 is swung at the tip of the boom 2 by an arm cylinder B. The bucket 4 is movably pivoted at the tip of the boot 6 and the bucket cylinder 7.
It is pivotably mounted by. P in the figure. P1 is the pivot point of the excavator body 1 and boom 2, P1 is the pivot point of the boom 2 and arm 5, P21-i is the pivot point of the arm 6 and bucket 4 (hereinafter referred to as the boot or tip point), and P6 is the bucket tip. represents a point.

To excavate the ground flat (hereinafter referred to as horizontal excavation) using a hydraulic shift bell, push the arm 6 forward and lower the boom 2 to reach the tip point P of the arm 6.
2 horizontally and the angle that the bucket 4 makes with the horizontal plane, that is, the absolute bucket angle, must be kept constant, but the operator must operate the boom cylinder 5, arm cylinder 6, and bucket cylinder 7 at the same time. This operation requires great skill and still causes significant operator fatigue.

Therefore, as shown in Figure 2, one end of the bucket cylinder 7 is pivoted to the boom 2 to form a pseudo-parallel link structure, and when the operator operates the boom 2 and arm 3, the absolute bucket angle is automatically maintained constant. As disclosed in Japanese Patent Publication No. 52-36883-'r'J', an auxiliary cylinder is installed between the boot, 2 and the arm 6 in addition to the 6 wood oil VI-7IJ cylinders. When the arm 6 is operated, the boot 2 descends in a 1'' direction and the arm tip point P2 moves horizontally.・Many ideas have been proposed. .

According to the various 41 plans for horizontal excavation mentioned above, not only can the hydraulic shovel move forward on the excavated ground without any problems, but also the excavation of the coal seam can cause soil to get mixed with the coal. Although it brings great advantages to excavation work using a hydraulic excavator, such as being able to effectively prevent the occurrence of damage, it also has the following disadvantages.

(1) As shown in Figure 3, in conventional horizontal excavation, excavation must be started from the front of the tracks 1 and 1 of the hydraulic excavator main body 1 by the length of one bucket, and the excavation length I.
6. Cannot take 1 to a large value. That is, in a normal loader excavator, the length from the crawler track 1a to the end of the final 1h1 cutting is hereinafter referred to as the horizontal excavation possible length) 1.

・ 6 ・ is equivalent to about 6 buckets, so especially when digging shallowly into the topsoil as shown in the figure, it is not possible to scoop up enough sand in one excavation, resulting in poor work efficiency.

(2) When pressing the ground 111, as shown in Fig. 4, the ground 8 is excavated, the lower part 8a of the ground is excavated flat, and then the ground 111 is excavated.
The novel body 1 is moved forward to excavate the earth.

Conventionally, so that the bucket 4 could excavate the ground above,
Once the crawler belt 1a is advanced near the point where the slope of the ground indicated by the solid line begins, the ground 8 is excavated. Thereafter, it is necessary to move the crawler track 1a backwards at the position shown by the two-dot chain line, put the bucket 4 in a position that allows horizontal excavation, and horizontally excavate the lower part of the rock 8a so that the ground is flat. However, in this case, the excavator body 1 must be moved backward each time the lower part 8a of the ground 111 is excavated, and the forward distance for the next excavation of the earth becomes longer, making the work troublesome and time-consuming. , work efficiency decreases.

This invention was made in order to solve the above-mentioned problems, and provides an excavation control device for a hydraulic excavator that can easily perform various types of excavation work to level the ground and has good work efficiency. (Jl, to do [1 target.

In order to achieve this object, the present invention d provides the speed of the boom cylinder when the bucket is rotated and the locus of movement of the cutting edge point of the bucket becomes a straight line from at least one of the bucket angle and the bucket angular velocity. That is, the present invention is characterized in that it includes a calculation device that calculates a control speed, and a flow rate control device that controls the boom cylinder using the control speed.

The invention will now be explained with reference to FIGS. 5 and 6. FIG. 5 is a diagram showing an example of the operation of the hydraulic 7-min saw according to the present invention, in which the bucket 4 is rotated from a state in which the blade of the bucket 4 is erected almost vertically at a position close to the crawler track 1a. Push out the arm 6 while lowering the boom 2, or lower the boom 2 while rotating the bucket 4, so that the bucket tip point 1.3 always remains horizontal to the ground. If we do this, we will be able to horizontally excavate the ground in front of the main body of the summer bell (hereinafter referred to as "front horizontal excavation"). As shown in the figure, when combined with conventional horizontal excavation, even when shallowly excavating topsoil, the excavation length becomes I.2, which is almost equal to the horizontal excavation length 1.2, which requires one excavation compared to the conventional method. Furthermore, as shown in Fig. 6, when excavating the ground, the lower part of the ground 8a is often moved back by hydraulically moving the shovel body 1 after excavating the ground 1118. Can be excavated flat.

In this case, after excavating the ground 1118, only the front excavation is performed to flatten the ground 1+8;l, and the hydraulic excavator main body 1
may be advanced, and then the earth 8 may be excavated, or the lower part of the earth 8X1 may be performed by a combination of front horizontal excavation and conventional horizontal excavation.

However, in this front horizontal excavation, while rotating the bucket 4 as described above, the boom 2 is lowered and the bucket tip point [ ) 3 is moved while keeping it horizontal to the ground. In addition, it requires a boot and six extrusion operations, making it an extremely difficult task even for experienced operators. This invention: To facilitate this front excavation work and to achieve the above object.

FIG. 7 is a diagram showing the positional relationship of the front portion of the loading hydraulic excavator shown in FIGS. 1 and 2. FIG. In the figure, α is the angle of the boom 2 with respect to the excavator body 1, that is, the boom angle, β is the angle of the arm 6 with respect to the boom 2, that is, the arm angle, γ is the angle of the bucket 4 with respect to the arm 6, that is, the bucket angle, and 11 to 13 are respectively Boom 2, arm 6
, the length of the bucket 4, 11 is the pivot point P of the boom 2.

1] is the height of the cutting edge point P3 of the bucket 4.

In this case, the height 11 can be expressed by the following equation.

h2ho+11S1nα-12sin (α+β)+
13 sin (α+β+r) (1) Therefore, the arm angle β is set to the predetermined value β. When only the bucket 4 is rotated after closing, in order to move the cutting edge point P6 horizontally, β-β is used in equation (1). Find the height 11 from the boom angle α and bucket angle γ using the formula by substituting
The boot and cylinder 5 may be controlled according to the deviation from the above. When moving the bucket 4 and the arm 3, the bucket 4, 7. When operating the arm 4, and moving the boot and arm according to the movement of the bucket 4, the bucket 4, the boot,
3 in a predetermined functional relationship, use equation (1) to calculate the height l from the boot angle α, arm angle β, and bucket angle γ.
By determining this and controlling the boom cylinder 5 according to the deviation between the target height and the height 1, the cutting edge point P3 can be moved horizontally.

From equation (1), find the boom angle α as shown in the following equation.

α=li″(β, γ, +1) (2)
Therefore, the arm angle β is set to the predetermined value β. When only the bucket 4 is rotated after closing, β-β is calculated in equation (2). ,1
The target boom color is calculated from the bucket angle α using the equation in which 1-e is substituted, and when moving the bucket 4 and the arm 3, the arm angle β and bucket angle γ are calculated by substituting h-Q into the equation (2). If the target boom itself is determined from , and the packet cylinder 5 is controlled according to the deviation between the target boom color and the boom angle α, the cutting edge point 1) 3 can be moved horizontally.

Furthermore, when height 1] is constant, we can differentiate equation (1) and
8 ・Then, the following formula is obtained.

Q = (11cosα”72cos(α”-β)
10e3cos' (1?-1-β10γ)ld+ (-1
2cos (α+β) -I-13C(18(α''-β
'-γ)) β+130O5(α+β-1-r) y(
3) Therefore, set the arm angle β to the predetermined value β. When moving only the bucket 4 after closing, the arm angular velocity table is zero, so in equation (3), β - β. , 10 are substituted into the equation to find the target boom and angular velocity from the boom angle α, bucket angle γ, and bucket angular velocity. When moving the bucket 4 and arm 6, the boom angle α and arm are calculated using equation (3). From the angle β, bucket angle γ, arm angular velocity table, and bucket angular velocity n, [
If the target boom angular velocity is determined and the boom cylinder 5 is controlled according to the target boom angular velocity, the cutting edge point P3 can be moved horizontally.

Furthermore, by combining the control based on equation (3) with the control based on equations (1) and (2), control shifts can be achieved with extremely high accuracy.

FIG. 8N is a diagram showing an excavation control device for a hydraulic shovel according to the present invention. In the figure, 9.10 is an angle detector that detects the boom angle α and bucket angle γ, respectively; 11 is a differentiator that differentiates the bucket angle γ to find the bucket angular velocity r;
12 is a flow rate control device that controls the speed of the boom cylinder 5, and 13 is the boom cylinder 5 when the cutting edge point P3 of the bucket 4 moves horizontally when the bucket 4 is rotated.
According to the speed of? An arithmetic unit 14 that calculates the control speed Ii and outputs the control speed to the flow rate control device 12 is a scale function unit that calculates a function f1 of the following equation.

△ degrees, that is, △ 'Iy to find the 1-mark boom cylinder speed yct, where the n-mark boom/linda speed y changes depending on the boom angle α. 17 is the output of the function unit 16. Control speed flow f1'c control device +i''? 12 human power liM, and this nonlinear 1'l
This is an amplifier that performs compensation such as ff.

In this excavation control device, Ull, boot, and angle β are set to predetermined values β. If only the bucket 4 is moved after closing, the arm angle β in equation (3) becomes a constant β. Since the arm angular velocity force is -dg, the arithmetic unit 13 calculates the cutting edge point 1 from the boom angle α, bucket angle γ, and bucket angular velocity.
When ゛6 moves to water and soil, the control △ speed, that is, the target boom/linda speed IW is determined,
Since the boom cylinder 5 is controlled by the flow rate control device 12 according to the control speed, the boom 2 moves upward and downward at a target boom angular velocity α, and the cutting edge point 1'3 moves horizontally.

FIG. 9 is a diagram showing another hydraulic/1-bell excavation control device according to the present invention. In the figure 18 u (+) β-β in the equation. Boot, angle (Y, bucket angle γ
Find height 11 from height expression 3'') vessel, 19&J, :l
A memory device 20 stores the height 1 at the time of control start as the target height.
11 ・ Find the height deviation Δ11 Adder/subtractor, 21 is the height deviation Δ
11 is multiplied by a gain of 1<, and the optimum value of the gain of 1<1 is selected within the range where the system does not ache. 2
2 is an adder that adds 1Δ11 to the target boom cylinder speed party □.

In this excavation control device, the arm angle β is set to a predetermined value β.

If only the bucket 4 is moved after this, the arm angle β becomes a constant β in equation (1). Therefore, the height 11 can be calculated from the boom angle α, ·(kerato angle γ) using the height calculator 18.Then, the value l obtained by multiplying the height deviation Δh by the gain is
Since the boom cylinder 5 is controlled according to the sum of Δ11 and the target boom cylinder speed, that is, the control speed, if the boom cylinder 5 is moved to the target and the height 1 deviates from the target height, , this deviation is corrected by I(1Δ1), so the cutting edge point P can be moved horizontally with high precision.

FIG. 10 is a diagram showing another excavation control device for a hydraulic excavator according to the invention. In the figure, 26 is an angle detector that detects arm angle β, 24 is a differentiator that differentiates arm angle β to obtain arm angular velocity force, and 25 is a flow that controls the speed of arm cylinder B. Control devices 26 and 27 are function units that calculate functions 12 and f3 of the following equations, respectively.

28 is a multiplier for calculating 12λ, 29 is an 11 multiplier 15.
An adder which adds the outputs of 28 and obtains the target boom angular velocity; 60 is a function which obtains the arm angular velocity table for the bucket angular velocity i; a function unit which divides 4; 61 obtains the target angular velocity. A multiplier 62 converts the speed of the arm cylinder 6 corresponding to the target arm angular velocity, that is, a target arm multiplier 33 converts the output of the function unit 62 to become an input signal of the flow rate control device 25, and also compensates for this nonlinearity. This is an amplifier that performs

In this excavation control device, when the bucket 4 is operated, the Arton cylinder 6 moves up and down at the target boom/ring/linda 5 at a control speed, that is, the target boom/ring ), so the cutting edge point P should move horizontally.

? P, 11 FIG. 11 is a diagram showing another excavation control device for a hydraulic shovel according to the present invention. In the figure, 41 is (1)
Find the height 11 using the formula Boolean l, angle α, arm angle β, and bucket angle γ. Height calculation 2K, 64 is 1 from bucket angle γ.
Find the 1-mark Ato angle. Use the gate Pi to calculate the function g.
Seki v! Let ig be a function representing the following equation.

14-F Ig-'r, and 9=rn.35 is the difference between the target arm angle and arm angle β, that is, the arm angle deviation Δβ. Using a coefficient multiplier that multiplies Δβ by the gain 1, select the optimum value for the gain within a range where the 2-ba system does not hunt. 67
is an adder that adds 2Δβ to the target Boono, cylinder speed [W, et al.

In this excavation control device, when the bucket 4 is operated -t, the arm cylinder 6 responds to the sum of the target arm cylinder velocity yβ and the value K Δβ obtained by multiplying the arm angle deviation Δβ by the gain 1<. Because it is controlled
If Boo 3 swings at the target angular velocity and the arm angle β is far from the target arm angle, this deviation is compensated by 1<, Δβ, so arm 5 is predetermined. It follows the movement of f, 11 degrees well. Moreover, the control of the boom 2 is similar to that shown in FIG. 9, and the cutting edge point 1) 3 is moved horizontally with high accuracy.

As can be seen from the above embodiments, the angle β is set to a predetermined value β. When only the bucket 4 is moved 12 after closing and the arm 6 is not moved (Figs. 8 and 9), the angle detector 23 is omitted because there is no need to detect the boolean l and the angle β. However, if the angle detector 26 is provided, control can be performed even if the arm angle β at the start of control changes. Well, when the arm 6 is not moving, the function unit 27, multiplier 28, and adder 29 are unnecessary, so the configuration of the arithmetic unit 13 becomes a component. Also, Figure 8,
In the embodiment shown in FIG. 10, the target boom cylinder speed y is used as the control speed, but K1Δh may be used as the β control speed. Furthermore, Figures 9 and 11
In the example shown in the figure, instead of K1Δ1], the value 1<,Δα, which is the difference between the target boom/opposite direction and the boom angle α calculated using equation (2), that is, the boom angle deviation Δα multiplied by the gain by 3, is used. It's okay. Furthermore, in the embodiment shown in FIG.
In place of the arm angle β, we use the target Boo 4 angle angle and also use the BU 7. Using the angle 7, target arm color, and 11 altitude, use the target boom self according to equation (2), and further use the target arm angular velocity table instead of the boo angular velocity table, the angle detector 9
．． 23.16. And the differentiator 24 can be omitted.

By the way, when only the bucket 4 is moved and the front posture is always constant when starting control to move the cutting edge point P3 horizontally, the arm angle β and height 11 are constant in equation (2), so The boot angle α is a function only of the bucket angle γ, and since the boot angle α is a function of the bucket angle γ and the bucket angular velocity is zero and the arm angle β is constant, the boom angular velocity (1 is a function of the bucket angle γ and the bucket angular velocity Totoro.And since the initial value of the bucket angle γ is constant,
The bucket angle γ can be calculated by integrating the bucket angular velocity i. It can be found from A) Be able to do it. Furthermore, since the signal commanding the speed of the bucket 4 corresponds to the bucket angular velocity n, the bucket angular velocity n can be found from the above signal.

FIG. 12 is a diagram showing another excavation control device for a hydraulic excavator according to the present invention, and this excavation control device is an application of the above-mentioned method. In the figure, 68 is a speed command device that commands the speed of the bucket 4, and the speed command device 68 consists of a bucket operating lever and a device that outputs a signal corresponding to the amount of operation of the operating lever. 69 is a flow rate control device that controls the speed of the bucket cylinder 7 based on the signal from the speed command device 38; 40 is a speed command detector for determining the bucket angular velocity from the signal from the speed command device 38;
calculates the function f5 to obtain the target boom cylinder speed command from the bucket angular velocity.

α In this excavation control device, after setting the front to a predetermined posture, the speed command device 68 is operated (
The bucket cylinder 7 operates at a speed according to ↑1, and the bucket 4 rotates. Then, the speed command detector 40 determines the bucket angular velocity t, and the arithmetic unit 16 determines the target boom cylinder speed y(t) from the bucket angular velocity t using the function f5.
The boom cylinder 5 has a controlled speed of 11 points, 2
Since the target boo moves up and down at the angular velocity stop, the cutting edge point P3
moves horizontally.

Furthermore, only the bucket 4 is moved and the cutting edge point P3 is
When the front attitude is always constant at the time of starting the horizontal movement control, as mentioned above, the boom angle α is a function only of the bucket angle γ, so the target boom 7 is determined from only l+1 bucket angle. , find the hue, differentiate the 11 mark boom angle ◇ to find the target boot and angular velocity stop, and then find the target boom cylinder speed - from the target boom angular velocity and the 11 mark boo...hue △, and calculate the 11 mark 1 If the boom cylinder 5 is controlled by α using the Munlinda speed command, the cutting edge point 1.6 can be moved horizontally.

In addition, in the above embodiment, (+: 1, the case where the cutting edge point 1゛3 is moved horizontally was explained, but it is natural that the moving locus of the cutting edge point P3 can be made into an arbitrary straight line. Further, this invention is characterized in that when the Mohake Note 4 is rotated in the digging direction, the boom 2 is controlled to make the movement locus of the cutting edge point P3 a straight line. Other linear trajectory control, such as horizontal excavation, may be added, and the control in this case may be switched depending on the front angle condition, for example, and this can be easily done using conventional technology. In the above embodiment, when the bucket 4 and the arm 6 are moved simultaneously (FIGS. 10 and 11), the arm 6 follows the bucket 4, but the bucket 4 and the arm 6 may be operated manually respectively. , or the bucket 4 and the arm 6 may be moved simultaneously in a predetermined functional relationship. This functional relationship should be determined so that optimal excavation can be performed.Furthermore, the functions r1 to f5 in the above embodiments are It is also possible to give an appropriate approximate curve.The flow rate control device 12 may be a combination of an electro-hydraulic conversion valve and a flow rate control valve, or a device that controls the pump discharge flow rate using an electro-hydraulic conversion valve. However, in the case of the embodiment shown in FIG. Furthermore, in the above embodiment, an analog arithmetic unit is used as the arithmetic unit 13, but a microconbeater may be used, and in this case, the d packet angle γ, Differentiation of the arm angle β may also be performed using a microconbeater.In the dual embodiment, the angle detector 9. 10.26 was used, but the boom angle α, etc. may be determined from the strokes of the boom cylinder 5, arm cylinder 6°, bucket cylinder 7, etc. Furthermore, in the double embodiment, the arm angle β,
By differentiating the bucket angle γ, the arm angular velocity force,
Although the bucket angular velocity was determined, it may also be determined from the velocities of the arm cylinder 6, bucket cylinder 7, etc.

The invention described above has the following effects.

(1) Horizontal excavation on the front side of the excavator body (front horizontal excavation) can be easily performed by the operator by operating the bucket or by giving a single speed instruction signal, and can be used for horizontal excavation of topsoil or ground excavation. It is possible to perform ground leveling work very efficiently.

(2) By combining the front horizontal excavation of this invention with the conventional horizontal excavation, the horizontal excavation length increases, and the float/tower structure has to be changed, which is the same as when the front reach is lengthened. You can get the effect of

(3) When excavating the lower part of a mountain, there is no need to move the excavator backwards, and the forward distance is shortened, reducing the work cycle and reducing the size of the excavator. It also reduces operator fatigue.

The effect of this invention is remarkable.

[Brief explanation of the drawing]

Fig. 1 is a side view showing the front part of the fcl loading hydraulic/yield, Fig. 2 is a side view showing the front part of the loading hydraulic/yield equipped with pseudo-parallel links, and Fig. 3 is a side view showing the front part of the fcl loading hydraulic/yield. A diagram explaining the operation of excavating the ground 111, Figure 4 k), a diagram explaining the operation of excavating the ground 111,
FIG. 5 is an explanatory diagram of the operation of cutting 114'X1"-114'Ai according to the present invention, and FIG.
An explanatory diagram of the operation of excavating Cl-1, Fig. 7 shows the positional relationship of the front part of the mi-loading hydraulic shovel-J-t
'21, Fig. 8 and Fig. 12 are diagrams showing an excavation control device for a hydraulic engine I-4 according to the present invention. 1...Jobbel body 2.Boom 6...Arm 4.Bucket 5...Boom cylinder 6...Boot 11 Cylinder 7...Bake no tonri/da 9.10...Angle detection z:)11.
...Differentiator 12...Flow: 11''il control device (613...Arithmetic unit 14...Function unit 15
... Multiplier 16... Function unit 17... Amplifier 18... Height operation unit::19... Memory unit 20... Addition/subtraction unit 21... Coefficient unit
22 Add three: ;26... Angle detector 2
4. Differential 2) (26, 27...Function unit 28...
Rider 23, 29...Adder 4o...Speed command detector 41, Height calculator Proxy valve Ato 1- Junnosuke Nakamura, 24 ゛Continued from page 1 0 Inventor Yukio Aoyagi Tsuchiura City 650 Kandatecho, Hitachi Construction Machinery Co., Ltd., Tsuchiura Factory 0 Author: Koji Asai, Hitachi Construction Machinery Co., Ltd. Tsuchiura Factory, 650 Kandatecho, Tsuchiura City

Claims (2)

[Claims] (1) A boom pivotably attached to the main body, which is moved up and down by a boom cylinder, an arm pivoted to the tip of the boot, which is pivoted to the tip of the boom cylinder, and a bucket cylinder, which is pivoted to the tip of the arm. Rotated, Robakeno 1
Oil 1 having ~ [in the excavation control device of an excavator,
When the bucket is rotated, calculate the speed of the boom cylinder, that is, the control speed, when the movement locus of the cutting edge point of the bucket becomes a straight line from at least one of the bucket angle and the bucket angular velocity. It is equipped with a flow control device that controls the two-part boot and cylinder at its controlled speed! Excavation control device for hydraulic excavators with 14 features. (2) As a two-part calculation device, when the bucket is rotated and the boot is swung, at least one of the bucket angle and the bucket angular velocity -fi (one of the bucket angle and the arm angle and the arm angular velocity The speed of the boom cylinder when the locus of movement of the point of the cutting edge of the blade becomes a straight line, that is, the speed of the boom cylinder from at least one of the following: An excavation control device for a hydraulic excavator as described in the patent.