JP2871890B2 - Excavator excavation control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic excavator excavation control apparatus suitable for excavating work of a hydraulic excavator, particularly for horizontal excavation.

[0002]

2. Description of the Related Art Hydraulic excavators have various work applications, but most of them are excavation work using buckets.
Such a hydraulic excavator will be described with reference to the drawings. FIG. 8 is a side view of the excavator. In the figure, 1 is a lower traveling body of a hydraulic excavator, 2 is a revolving superstructure (main body) on the upper side of the lower traveling body 1, 21 is a cab provided in the main body 2, and 3 is rotatably mounted on the main body 2. It is a front mechanism. The front mechanism 3 includes a boom 31 rotatably mounted on the main body 2, an arm 32 rotatably mounted on the boom 31, and a bucket 33 rotatably mounted on the arm 32. . The boom 31 is driven by a boom cylinder mounted between the main body 2, the arm 32 is driven by an arm cylinder mounted between the main body 2, and the bucket 33 is mounted between the arm 32 and the arm 33. These cylinders (hydraulic cylinders) are not shown in the figure. A is boom 31 and body 3
An angle sensor for detecting an angle between the arm 32 and B;
An angle sensor for detecting an angle between the arm 33 and the bucket 33; and an angle sensor C for detecting an angle between the arm 33 and the bucket 33. Each of these angle sensors A, B, and C outputs an electric signal proportional to the detected angle. Although not shown, the cab 21 is provided with operation levers for operating the boom 31, the arm 32, and the bucket 33. When each of the operation levers is operated, an electric signal corresponding to the operation amount is output, and the angle Based on the output of the sensor and the output of the manipulated variable, a flow control valve interposed between the hydraulic pump and each of the hydraulic cylinders is controlled. As a result, each of the hydraulic cylinders, that is, the boom 31, the arm 32, and the bucket 33 are controlled. Is driven, and excavation work is performed.

[0003]

Since the front mechanism 3 of the hydraulic excavator is composed of the three components of the boom 31, the arm 32 and the bucket 33 as described above, these are individually operated to perform desired excavation. For this purpose, considerable skill is required, and in particular, the work of excavating the ground on the same plane without unevenness (hereinafter referred to as horizontal excavation) requires a high level of skill. For this reason, a control device for performing horizontal excavation separately from normal control has been proposed in, for example, Japanese Patent Application Laid-Open No. 49-132801. With such a control device,
Horizontal excavation can be automatically performed simply by operating the arm 32 or the arm 32 and the boom 31. by the way,
In order to perform horizontal excavation automatically by the control device, it is necessary to instruct horizontal excavation using a switch or the like, and to return to normal excavation, it is necessary to cancel the instruction.
Therefore, it is extremely troublesome for the operator to perform this during the excavation work, especially when there is a repetition of horizontal excavation and normal excavation, the command of the horizontal excavation and its release must be repeated. Not only that, the work efficiency may be reduced. An object of the present invention is to solve the above-mentioned problems in the prior art and to provide a hydraulic shovel excavation control device capable of switching to horizontal excavation without any trouble.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a hydraulic excavator body having a front mechanism composed of boom, arm and bucket components rotatably mounted thereon. Each angle sensor for detecting the relative angle of each, each operation amount sensor for detecting the operation amount of each operation body of each actuator for driving each component, each of the angle sensor and each operation amount sensor A first calculating unit for calculating a command value for driving each of the actuators based on the detected value; and each of the actuators for causing the front mechanism to perform horizontal excavation based on a required one of the detected values. And a second calculating unit for calculating a command value for driving the excavator, the excavation control device for a hydraulic shovel comprising: Expected trajectory calculating means for calculating a thought trajectory, and switching means for switching the input of each of the detected values to the first calculating part to the second calculating part when an angle of the predicted trajectory with respect to a horizontal plane is smaller than a predetermined angle. Is provided. Further, in the excavation control device for a hydraulic shovel, when the switching to the second calculation unit is performed by the switching unit, an angle to be compared with an angle of the predicted trajectory with respect to a horizontal plane may be larger than the predetermined angle. It is also characterized by the setting angle of. Further, the present invention provides the hydraulic shovel excavation control device, wherein an inclination angle sensor for detecting an inclination angle of the main body, and inclination correction means for correcting an angle of the predicted trajectory with respect to a horizontal plane with the inclination angle are provided. Also features. Further, the present invention provides the hydraulic shovel excavation control device, wherein a slope angle setting unit for setting an angle of the excavation slope, and an angle of the expected trajectory with respect to a horizontal plane at the angle set by the slope angle setting unit. It is also characterized in that a slope angle correcting means for correcting is provided. Furthermore,
The present invention provides the excavator excavation control device described above,
Horizontal excavation canceling means for constantly inputting each of the detected values to the first calculation unit is provided.

[0005]

During the excavation work, the predicted trajectory calculation means inputs the boom angle, the arm angle, the bucket angle, the boom operation amount, the arm operation amount, and the bucket operation amount, and calculates the trajectory of the bucket tip based on the input. The angle with respect to the horizontal plane is obtained from the vector obtained in this way, and the angle is compared with a preset angle (the angle for determining whether or not horizontal excavation is performed). The second arithmetic unit (horizontal excavation control) is switched to the first arithmetic unit (normal excavation control) by the switching means when the former is greater than the latter. Further, once the horizontal pulling mode is entered, stable horizontal excavation can be performed by setting the angle to be compared with the angle with respect to the horizontal plane to be larger than the preset angle. Further, if the tilt angle sensor is used, even if the hydraulic excavator body is tilted, horizontal excavation can be performed without hindrance by correcting the angle with respect to the horizontal plane obtained by the predicted trajectory calculation means by the tilt angle. Further, also in the case of the slope excavation, the slope excavation intended by the operator can be performed by correcting the angle with respect to the horizontal plane by the angle set in the slope angle setting unit. Furthermore, if it is known in advance that horizontal excavation is not to be performed, by operating the horizontal excavation canceling means, control by the second arithmetic unit is prohibited regardless of the angle with respect to the horizontal plane,
Only the control by the first calculation unit can be performed.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 1 is a block diagram of an excavation control device for a hydraulic shovel according to an embodiment of the present invention. In the figure, A, B and C are shown in FIG.
This is the same angle sensor as that shown in FIG. Reference numerals 5 and 6 denote operation levers (joystick levers).
For example, when the boom 31 is pulled forward, the boom 31 is raised, and when the boom 31 is tilted outward, the bucket 33 is dumped.
Becomes an arm 32 dump when it is tilted outward, for example.
D detects the operating angle (in proportion to the manipulation amount) theta ₃₁ of the boom driving operation of the operating lever 5, an angle sensor for outputting an electrical signal corresponding thereto, E is the bucket driving operation of the operating lever 5 operating angle (Operation An angle sensor that detects θ ₃₃ and outputs an electric signal in accordance with the detected angle. F detects an operation angle (proportional to the operation amount) θ ₃₂ of the arm driving operation of the operation lever 6 and responds accordingly. It is an angle sensor that outputs an electric signal. Reference numeral 7 denotes a mode switching operation unit that inputs detection signals of the angle sensors A to F and performs a required operation. Reference numeral 8 denotes a normal mode operation unit that controls the boom 31, the arm 32, and the bucket 33 in accordance with the operation of the operation levers 5 and 6 based on the detection signals of the angle sensors A to F. Reference numeral 9 denotes a horizontal pulling mode calculation unit, and each angle sensor A
The control for driving the boom 31, the arm 32, and the bucket 33 based on the detection signals of .about.F to perform automatic horizontal excavation is performed. Reference numeral 10 denotes a mode switching unit that operates in accordance with a command from the mode switching calculation unit 7, and switches and inputs detection signals of the angle sensors A to F to either the normal mode calculation unit 8 or the horizontal pulling mode calculation unit 9. 31V, 32V, and 33V are a boom control valve, an arm control valve, and a bucket control valve, respectively, which are operated by control signals of the normal mode operation unit 8 or the horizontal pulling mode operation unit 9 to drive the boom 31, the arm 32, and the bucket 33. To control the flow rate of pressure oil to each hydraulic cylinder. The above is the basic configuration of the present embodiment. Here, reference numeral 1 shown in FIG.
Reference numeral 1 denotes an apparatus used in each of the other embodiments of the present invention. Since these devices are devices that are appropriately added to the above basic configuration, they are additionally shown in FIG.
Each of the devices 111, 112, 113 indicated by reference numeral 11
This will be described in the description of each embodiment.

Next, the operation of the above-described basic configuration of the present embodiment (first embodiment) will be described with reference to the dimensions and angles of the respective parts shown in FIG. 8, the mathematical expressions shown in FIG. 2, and the flowchart shown in FIG. explain. FIG. 3 is a flowchart showing the operation of the mode switching operation section 7 shown in FIG. First, the angles and dimensions of each part shown in FIG. 8 will be described. a indicates a boom angle detected by the angle sensor A, b indicates an arm angle detected by the angle sensor B, and c indicates a bucket angle detected by the angle sensor C. Each of the angle sensors A, B, and C is installed such that its rotation axis coincides with the rotation axis of the boom 31, the arm 32, and the bucket 33, respectively. L ₃₁ is an angle sensor A,
The distance between B (boom length), L ₃₂ is an angle sensor B, the distance between C (arm length), L ₃₃ is the angle sensor B and the distance between the bucket tip T (bucket length), phi is The angle formed between the expected trajectory V of the bucket tip T and the horizontal line is shown. The expected trajectory V will be described later.

FIG. 2 is a diagram showing mathematical formulas calculated by the mode switching calculator 7. X at the tip of the bucket shown in FIG.
The coordinate can be obtained by equation (1), and the y coordinate can be obtained by equation (2). Each value of each of the equations (1) and (2) is known. The operation angles (operation amounts) of the operation levers 5 and 6 are determined by the boom 31, the arm 32, and the bucket 33 which are the operation targets.
Can be regarded as an indication value of the rate of change of the angular displacement of. Therefore, the angles a to c and the operation angles θ of the operation levers 5 and 6 are
The relationship with _{31 to} θ ₃₃ is given by the equations (3), (4), and
It is represented by (5). Eventually, from equations (3) to (5), angles a to c expected at the moment when operating levers 5 and 6 are operated are shown in equations (6), (7) and (8) in FIG. As described above, the current angle a ₀₀ , b ₀₀ , c ₀₀ is a value obtained by adding the expected angle change obtained by the operation angle. By the way, at the current position of the bucket tip T, the speed of the expected trajectory at the moment when the operation levers 5 and 6 are operated is given by the above equation (1).
It can be calculated by differentiating the coordinate values x and y obtained in (2), and the angle φ can be obtained by differentiating the coordinate value y.

In the excavation work of the hydraulic excavator, the mode switching calculating section 7 detects the detected values θ ₃₁ , θ ₃₁ of the angle sensors AF.
₃₂ , θ ₃₃ , a, b, and c are input (step S _{11 in the} flowchart shown in FIG. 3), and equations (1) and (2) shown in FIG. 2 are calculated (step S ₁₂ ). to (Step S _13).
In this differentiation, it is difficult to differentiate the equation (2) shown in FIG. 2, but it is possible to solve this numerically. For this purpose, equations (6) to (8) shown in FIG. 2 are used.
By the procedure S _13, predicted locus V bucket end T is obtained. Then, the differential value of the value y obtained by the calculation procedure S ₁₃ and the angle phi (Step S _14), the angle phi,
A comparison is made with a predetermined value φ ₀₀ (step S ₁₅ ). Angle φ
Is smaller than the value φ ₀₀ , the mode switching operation unit 7 outputs a command signal to the mode switching unit 10 and performs switching to input the detection signals of the angle sensors A to F to the horizontal pulling mode operation unit 9. As a result, the front mechanism 3 of the excavator is automatically driven according to the horizontal pulling mode. Following the processing steps S _16, whether the work by the hydraulic excavator is completed is determined by the power OFF or the like (Step S _17), if not finished, the process returns to step S ₁₁ again. On the other hand, in the comparison step S _15, if the angle phi is determined that the value phi ₀₀ or more, the mode switching operation unit 7 outputs a command signal to the mode switching unit 10, the detection signal of the angle sensor A~F was subjected to switching for inputting the normal mode operation unit 8 (Step S _18), performs the determination of the subsequent steps S _17. Thus, in this embodiment, calculates a predicted locus of the bucket tip T, hours the angle phi is less than a predetermined value phi _00, since to carry out drilling by automatically horizontally pulling mode, the hydraulic excavator The operator does not need any trouble for performing horizontal excavation, and can improve work efficiency.

FIG. 4 is a flowchart of a mode switching operation section of a hydraulic shovel excavation control device according to a second embodiment of the present invention. In the present embodiment, the apparatus 11 shown in FIG. 1 is not used, and the processing procedure of the mode switching operation unit 7 in the previous embodiment (basic configuration) is changed. That is, in this embodiment,
If the excavation once enters the horizontal pulling mode, control is performed to eliminate fluctuations between the excavation and the normal excavation and to surely execute the horizontal excavation. In FIG. 4, the same steps as those shown in FIG. 3 are denoted by the same reference numerals. In this calculation example, first, the flag Fr
The g and 0 (Step S _20), performs the processing of steps S ₁₁ ~ Step S _14. After the processing of steps S _14, whether or not the flag Frg the mode switching operation section 7 is 0 is determined (Step S _21). When the flag Frg is 0 (when not in the horizontal pulling mode), it is determined whether or not the angle φ is smaller than the value φ ₀₀ described above (step S ₁₅ ). If the angle φ is smaller, the flag Frg is set to 1 (step S ₁₅ ).
_22), thereafter procedure S _16, the processing of steps S ₁₇ performed. on the other hand,
If the flag Frg in step S ₂₁ is determined to 1 (if contained in a horizontal pulling mode), the angle phi is compared to a value slightly greater phi ₀₁ than the value phi ₀₀ (Step S _23), the angle phi values φ
If it is less than _01, the process proceeds to the process of steps S _16, continues the horizontal pull mode. In step S _23, the angle φ is the value φ
If it is determined that ₀₁ or more, the flag Frg to 0 (Step S _24), for switching to the normal mode operation unit 8.
Furthermore, when the angle phi is determined to be the value phi ₀₀ or more (not horizontal drilling) in step S _15, the process proceeds to step S _24. As described above, the mode up to the previous time is determined using the flag Frg, and if the horizontal pulling mode has been entered, a process for continuing the mode is performed. It is expected that the implementation will be more reliable than that of

Next, a third embodiment of the present invention will be described.
In this embodiment, in addition to the basic configuration, the apparatus 1 shown in FIG.
11 is used. The device 111 is a tilt angle sensor and has a weight G. The inclination angle sensor 111 is installed at an appropriate position on the body 2 of the excavator to detect the inclination angle Φ of the excavator, and outputs an electric signal proportional to the angle. FIG. 5 is a flow chart for explaining the operation of the mode switching operation section 7 of the third embodiment. The operation of the mode switching operation unit 7 of the present embodiment differs from the operation of the mode switching operation unit 7 of the above-described basic configuration only in the point that the inclination angle Φ is added as the angle φ. Is the same as the operation of the flowchart shown in FIG. That is, in FIG. 5, the same steps as those shown in FIG. 3 are denoted by the same reference numerals. Step S ₃₀ of the present embodiment corresponds to step S ₁₄ shown in FIG. 3, and the angle φ of the estimated locus by adding the inclination angle Φ on the differential value of the value y. As described above, in the present embodiment, the inclination angle of the hydraulic excavator is taken into consideration, so that in addition to the effects of the previous embodiment, horizontal excavation work on an inclined ground can be performed in the same manner as on a horizontal ground.

Next, a fourth embodiment of the present invention will be described. In this embodiment, in addition to the basic configuration, the device 11 shown in FIG.
2 is used. The device 112 is a cancel switch for preventing the apparatus from entering the horizontal pulling mode. FIG. 5 is a flow chart for explaining the operation of the mode switching operation section 7 of the fourth embodiment. The operation of the mode switching operation unit 7 of the present embodiment is different from the operation of the mode switching operation unit 7 of the above-described basic configuration.
The only difference is that the process for determining whether the flag is F is added, and the other operations are the same as those in the flowchart shown in FIG. That is, in FIG. 5, the same steps as those shown in FIG. 3 are denoted by the same reference numerals. Step S ₅₀ of this embodiment is a process of canceling switch 112 determines whether the ON or OFF,
When the cancel switch 112 is ON, switching to the normal mode operation unit is performed. Further, when the cancel switch 112 is OFF processing steps S ₁₅ is executed. Thus, in this embodiment, when horizontal excavation is not performed, the operator turns on the cancel switch 112.
By doing so, it is possible to avoid entering an unnecessary horizontal pulling mode.

Next, a fifth embodiment of the present invention will be described.
In this embodiment, in addition to the basic configuration, the apparatus 1 shown in FIG.
13 is used. The device 113 is a slope angle setting unit. When an arbitrary slope angle Ψ is set by a switch or a volume knob, an electric signal corresponding to the angle is output. The slope angle setting unit 113 is installed in the cab of the body 2 of the excavator, and the angle Ψ is set by the operator. FIG. 5 shows a mode switching operation unit 7 according to the fifth embodiment.
5 is a flowchart for explaining the operation of FIG. The operation of the mode switching operation unit 7 of the present embodiment is different from the operation of the mode switching operation unit 7 of the above-described basic configuration only in the point that the slope reduction angle Ψ is added as the angle φ. This is the same as the operation of the flowchart shown in FIG. That is, FIG.
The same steps as those shown in FIG. 3 are denoted by the same reference numerals. Step S ₆₀ of the present embodiment corresponds to step S ₁₄ shown in FIG. 3, and the angle φ of the estimated locus by adding the slope pull angle Ψ on the differential value of the value y. As described above, in the present embodiment, the angle φ is corrected by setting the slope angle of the hydraulic shovel, and in addition to the effects of the previous embodiment, the operator can operate at any angle other than the horizontal pull. You can perform the slope work as specified.

[0014]

As described above, according to the present invention, when the angle of the predicted trajectory of the tip of the bucket of the hydraulic shovel is smaller than the predetermined angle, the control by the horizontal pulling mode calculation unit is automatically performed. Without any operation, and
Horizontal excavation can be performed without reducing work efficiency. Further, once the horizontal pulling mode is entered, stable horizontal excavation can be performed by selecting a set large predetermined angle. Furthermore, by detecting the inclination angle of the excavator body and correcting the angle of the expected trajectory using this inclination angle, horizontal excavation can be performed even on an inclined ground. Also, a switch is provided to
By making the determination of N, OFF, it is possible to avoid using this switch to enter an unnecessary horizontal pulling mode when horizontal excavation is not performed. Also, by providing a slope angle setting unit to set an arbitrary angle,
Slope pulling work intended by the operator can be automatically performed.

[Brief description of the drawings]

FIG. 1 is a block diagram of an excavation control device for a hydraulic shovel according to an embodiment of the present invention. FIG. 2 is a diagram showing an arithmetic expression of the mode switching arithmetic unit shown in FIG. FIG. 3 is a flowchart for explaining the operation of the mode switching operation section shown in FIG. FIG. 4 is a second diagram for explaining the operation of the mode switching operation unit shown in FIG.
6 is a flowchart of the embodiment. FIG. 5 is a flowchart of the third embodiment for explaining the operation of the mode switching operation section shown in FIG. FIG. 6 is a flowchart of the fourth embodiment for explaining the operation of the mode switching operation section shown in FIG.
FIG. 7 is a flowchart of the fifth embodiment for explaining the operation of the mode switching operation section shown in FIG. FIG. 8 is a side view of the excavator.

[Explanation of symbols]

 Reference Signs List 5 operation lever 6 operation lever 7 mode switching calculation unit 8 normal mode calculation unit 9 horizontal pulling mode calculation unit 10 mode switching unit 111 tilt angle sensor 112 cancel switch 113 slope pulling angle setting unit A to F angle sensors

Claims (5)

(57) [Claims] 1. An angle sensor for rotatably mounting a front mechanism comprising components of a boom, an arm and a bucket to a hydraulic excavator body, and detecting respective relative angles of the components; An operation amount sensor that detects an operation amount of each operation body of each actuator that drives the element, and a command value for driving each actuator is calculated based on each detection value of each of the angle sensor and each operation amount sensor. A first calculation unit; and a second calculation unit that calculates a command value for driving each of the actuators for causing the front mechanism to perform horizontal excavation based on a required one of the detection values. A hydraulic shovel excavation control device, a predicted trajectory calculating means for calculating a predicted trajectory of the tip of the bucket based on the respective detected values; Switching means for switching the input of each of the detected values to the first arithmetic unit to the second arithmetic unit when an angle with respect to a horizontal plane is smaller than a predetermined angle. 2. The excavation control device for a hydraulic shovel according to claim 1, wherein when the switching to the second calculation unit is performed by the switching unit, an angle to be compared with an angle of the predicted trajectory with respect to a horizontal plane is set. An excavation control device for a hydraulic shovel, wherein the set angle is another set angle larger than the predetermined angle. 3. The excavation control device for a hydraulic shovel according to claim 1, further comprising: an inclination angle sensor for detecting an inclination angle of the main body; and inclination correction means for correcting an angle of the predicted trajectory with respect to a horizontal plane using the inclination angle. An excavation control device for a hydraulic excavator, wherein the excavation control device is provided. 4. The excavation control device for a hydraulic shovel according to claim 1, wherein a slope angle setting section for setting an angle of an excavation slope, and a horizontal plane of the predicted trajectory at the angle set by the slope angle setting section. An excavation control device for a hydraulic shovel, comprising: a slope angle correction unit for correcting an angle with respect to the excavator. 5. The excavation control device for a hydraulic excavator according to claim 1, further comprising a horizontal excavation canceling unit that inhibits switching to the second arithmetic unit.