JPH10159123A - Control device of construction machinery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To precisely and safely control a position and an attitude of a working member while restraining the cost to be low, concerning a control device of a construction machinery such as a hydraulic shovel to drill a ground, etc. SOLUTION: This control device is furnished with a construction machinery main body 100, a joint type arm mechanism one end of which is pivotally installed on the construction machinery main body 100, having a working member 400 on the other end side and having at least one pair of arm members 200, 300 connected to each other through a joint part, a cylinder type actuator mechanism having a plural number of cylinder type actuators 120-122 to drive the arm mechanism by making telescopic motion and angle detection means 20-22 to detect an attitude of the arm mechanism. Additionally, it is constituted of a conversion means 26 to convert angle information acquired by the angle detection means 20-22 to telescopic displacement information of the corresponding cylinder type actuators 120-122 and a control means 1 to control the cylinder type actuators 120-122 to be specified telescopic displacement in accordance with the telescopic displacement information of the cylinder type actuators 120-122 converted by the conversion means 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine such as a hydraulic shovel for excavating the ground, and more particularly to a control device for such a construction machine.

[0002]

2. Description of the Related Art As shown in FIG. 12, a construction machine such as a hydraulic shovel has a lower traveling body 5 having an infinite rail section 500A.
The upper revolving unit 100 with a driving operation room (cabin) 600 is provided on the upper revolving unit 100.
, Boom 200, stick 300, bucket 400
It is equipped with an articulated arm mechanism consisting of

Then, the stroke sensors 210, 22
Boom 200, stick 3 obtained at 0,230
00, the boom 200, the stick 300, and the bucket 400 are appropriately driven by the hydraulic cylinders 120, 121, and 122 based on the telescopic displacement information of the bucket 400 to excavate while keeping the traveling direction of the bucket or the posture of the bucket constant. As a result, the position and posture of a work member such as a bucket can be accurately and stably controlled.

[0004]

However, in such a conventional hydraulic excavator, the stroke sensors 210, 220, and 230 for detecting the expansion and contraction displacements of the boom 200, the stick 300, and the bucket 400 are expensive. Therefore, there is a problem that the cost is increased as a whole.

The present invention has been made in view of such problems, and provides a control device for a construction machine capable of accurately and stably controlling the position and orientation of a work member while keeping costs low. The purpose is to:

[0006]

SUMMARY OF THE INVENTION Accordingly, a control device for a construction machine according to the present invention has a construction machine main body, one end of which is pivotally connected to the construction machine main body, and a working member on the other end side.
An articulated arm mechanism having at least a pair of arm members connected to each other via a joint, a cylinder-type actuator mechanism having a plurality of cylinder-type actuators for driving the arm mechanism by performing expansion and contraction operations, and the arm Angle detecting means for detecting the posture of the mechanism with angle information, converting means for converting the angle information obtained by the angle detecting means into corresponding telescopic displacement information of the cylinder type actuator, and converting the angle information obtained by the converting means. It is characterized by comprising control means for controlling the cylinder type actuator to have a predetermined expansion / contraction displacement based on information on the expansion / contraction displacement of the cylinder type actuator.

The articulated arm mechanism is connected to a boom having one end rotatably connected to the construction machine body, and one end is rotatably connected to the boom via the joint. The working member may be configured as a bucket that is rotatably connected at one end to the stick via a joint and that can excavate the ground at the tip and store earth and sand therein. .

[0008] Further, the cylinder type actuator mechanism is interposed between the construction machine body and the boom, and a boom hydraulic pressure for rotating the boom with respect to the construction machine body by expanding and contracting the distance between the ends. A cylinder, a stick hydraulic cylinder interposed between the boom and the stick, and a stick hydraulic cylinder for rotating the stick relative to the boom by expanding and contracting the distance between the ends; A bucket hydraulic cylinder that is mounted and rotates the bucket with respect to the stick by expanding and contracting the distance between the ends may be used.

Further, the angle detecting means includes a first angle sensor for detecting the posture of the boom, a second angle sensor for detecting the posture of the stick, and a third angle sensor for detecting the posture of the bucket. You may comprise. Further, the conversion means may include a calculation means for calculating expansion / contraction displacement information of the cylinder type actuator corresponding to the angle information from the angle information obtained by the angle detection means, or may be obtained by the angle detection means. A storage means for storing expansion / contraction information of the cylinder type actuator corresponding to the angle information may be provided.

Further, the conversion means converts the angle information obtained by the first angle sensor into expansion / contraction displacement information of the boom hydraulic cylinder, and converts the angle information obtained by the second angle sensor into the stick hydraulic cylinder. And the angle information obtained by the third angle sensor may be converted into telescopic displacement information of the bucket hydraulic cylinder.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a hydraulic excavator as a construction machine according to the present embodiment includes an upper revolving superstructure (construction machine main body) 100 having a driving operation room 600 on a lower traveling body 500 having left and right endless rail sections 500A. It is provided rotatable in a horizontal plane.

Then, with respect to the upper swing body 100,
Boom (arm member) 20 whose one end is rotatably connected
0, and a stick (arm member) 300 whose one end is rotatably connected to the boom 200 via a joint. In addition, stick 30
A bucket (working member) 400 having one end rotatably connected to the base through an articulation portion and excavating the ground at its tip and capable of storing earth and sand therein is provided.

Thus, the boom 200 and the stick 3
The bucket 400 has one end pivotally connected to the upper revolving unit 100 and has the bucket 400 on the other end, and at least the boom 200 and the stick 300 as a pair of arm members connected to each other via a joint. Having an articulated arm mechanism. Also, a boom hydraulic cylinder 120, a stick hydraulic cylinder 121, and a bucket hydraulic cylinder 122 as cylinder type actuators
(Hereinafter, the boom hydraulic cylinder 120 will be referred to as the boom cylinder 1
20 or simply the cylinder 120, the stick hydraulic cylinder 121 may be called the stick cylinder 121 or simply the cylinder 121, and the bucket hydraulic cylinder 122 may be called the bucket cylinder 122 or simply the cylinder 122).

Here, one end of the boom cylinder 120 is rotatably connected to the upper swing body 100, and the other end is rotatably connected to the boom 200, ie, the upper swing body 100 The boom 200 is interposed between the boom 200 and the boom 200 by extending and contracting the distance between the ends.
00 can be rotated with respect to the upper swing body 100.

The stick cylinder 121 has one end rotatably connected to the boom 200 and the other end rotatably connected to the stick 300. That is, the stick cylinder 121 is connected between the boom 200 and the stick 300. The stick 300 can be rotated with respect to the boom 200 by being interposed therebetween and by expanding and contracting the distance between the ends.

Further, the bucket cylinder 122 has one end rotatably connected to the stick 300 and the other end rotatably connected to the bucket 400, that is, the connection between the stick 300 and the bucket 400. The bucket 400 can be rotated with respect to the stick 300 by being interposed between the sticks 300 as the distance between the ends expands and contracts. The bucket hydraulic cylinder 1
A link mechanism 130 is provided at the distal end of 22.

As described above, each of the cylinders 120 to 12
2, a cylinder-type actuator mechanism having a plurality of cylinder-type actuators for driving the arm mechanism by performing an extension / contraction operation is configured. Although not shown, a hydraulic motor that drives the left and right endless rail portions 500A and a turning motor that drives the upper turning body 100 to turn are also provided.

By the way, as shown in FIG.
Hydraulic circuits for the hydraulic motors and the swing motors are provided in the hydraulic circuits 20 to 122 and the pumps 51 and 52 driven by the engine E and the main control valve 1.
3, 14, 15 and the like are interposed. The main control valve 1
A pilot hydraulic circuit is provided to control the pilot pump 3, the pilot pump 50 driven by the engine E, the electromagnetic proportional valves 3A, 3B, 3C, and the electromagnetic switching valve 4A. , 4B, 4
C, selector valves 18A, 18B, 18C and the like are interposed.

By controlling the main control valves 13, 14, and 15 via the electromagnetic proportional valves 3A, 3B, and 3C, the boom 200, the stick 300, and the bucket 400 can be expanded or contracted in accordance with the mode to be controlled. A controller (control means) 1 for controlling the displacement is provided. The controller 1 includes a microprocessor, a memory such as a ROM and a RAM, and an appropriate input / output interface.

Then, detection signals (including setting signals) from various sensors are input to the controller 1, and the controller 1 performs the above-described control based on the detection signals from these sensors. Is to be executed. Note that such control by the controller 1 is referred to as semi-automatic control. Even in this semi-automatic excavation mode, fine adjustment of the bucket angle and the target slope height can be manually performed during excavation.

The semi-automatic control modes include a bucket angle control mode (see FIG. 7), a slope excavation mode (a bucket tip linear excavation mode or a raking mode) (see FIG. 8), a slope excavation mode and a bucket angle control. There are a smoothing mode (see FIG. 9) in combination with the mode, a bucket angle automatic return mode (auto return mode) (see FIG. 10), and the like.

Here, in the bucket angle control mode, as shown in FIG. 7, even when the stick 300 and the boom 200 are moved, the angle (bucket angle) of the bucket 400 with respect to the horizontal direction (vertical direction) is always kept constant. This mode is executed when the bucket angle control switch on the monitor panel 10 is turned on. The bucket 40
When 0 is manually moved, this mode is released, and the bucket angle at the time when the bucket 400 stops is stored as a new bucket holding angle.

The slope excavation mode is a mode in which the tip 112 of the bucket 400 moves linearly, as shown in FIG. However, the bucket cylinder 122 does not move. Also,
The bucket angle φ changes as the bucket 400 moves.
The slope excavation mode + bucket angle control mode (smoothing mode) is a mode in which the tip 112 of the bucket 400 moves linearly as shown in FIG. 9, and the bucket angle φ is also kept constant during excavation.

The bucket automatic return mode is a mode in which the bucket angle automatically returns to a preset angle, as shown in FIG.
Set by 0. This mode starts when the bucket automatic return start switch 7 on the bucket operation lever 6 is turned on. This mode is released when the bucket 400 returns to the preset angle.

Further, in the above-mentioned slope excavation mode and smoothing mode, the semi-automatic control switch on the monitor panel 10 is turned on, and the slope excavation switch 9 on the stick operation lever 8 is turned on. These modes are entered when both or one of the boom operation levers 6 is moved. The target slope angle is set by operating a switch on the monitor panel 10.

In the slope excavation mode and the smoothing mode, the operation amount of the stick operation lever 8 gives a bucket tip moving speed in a direction parallel to the target slope angle, and the operation amount of the boom operation lever 6 is in the vertical direction. Of the bucket tooth tip moving speed. Therefore, when the stick operation lever 8 is moved, the bucket tip 112 starts to move linearly along the target slope angle, and by moving the boom operation lever 6 during excavation, the target slope height can be manually adjusted. Adjustment is possible.

In the slope excavation mode and the smoothing mode, the bucket angle during excavation can be finely adjusted by operating the bucket operating lever 6, and the target slope height can also be changed. In this system, a manual mode is also possible. In this manual mode, the same operation as that of the conventional hydraulic excavator can be performed, and the coordinates of the bucket tip 112 can be displayed.

A service mode for performing service / maintenance of the whole semi-automatic system is also provided. This service mode is performed by connecting the controller 1 to the external terminal 2. And
In this service mode, control gain adjustment, initialization of each sensor, and the like are performed. By the way, as various sensors connected to the controller 1, as shown in FIG.
Pressure switch 16, pressure sensors 19, 28A, 28B,
Resolver (angle sensor) 20 to 22, tilt angle sensor 24
The controller 1 further includes an engine pump controller 27, an ON-OFF switch 7,
9. A monitor panel 10 with a target slope angle setting device is connected. The external terminal 2 is connected to the controller 1 when adjusting the control gain or initializing each sensor.

The engine pump controller 27
Is for controlling the engine E in response to the engine speed information from the engine speed sensor 23, and is capable of exchanging cooperative information with the controller 1. The detection signals from the resolvers 20 to 22 are input to the controller 1 via a signal converter (conversion means) 26.

The pressure sensor 19 is attached to a pilot pipe connected to the main control valves 13, 14, 15 from operating levers 6, 8 for extending and retracting the stick 300 and for raising and lowering the boom 200, respectively. Since the pilot oil pressure in the pilot pipe changes according to the operation amount of the operation levers 6, 8, the operation amount of the operation levers 6, 8 is estimated by measuring this oil pressure. I can do it.

The pressure sensors 28A and 28B detect the extension and contraction states of the boom cylinder 120 and the stick cylinder 121. The stick operating lever 8 is used to determine the bucket tip moving speed in the direction parallel to the set excavation slope, and the boom operating lever 6 is used to determine the bucket tip moving speed in the direction perpendicular to the set slope. Used as a decision. Therefore, when the stick operating lever 8 and the boom operating lever 6 are simultaneously operated, the moving direction and speed of the bucket tooth tip are determined by the combined vector in the direction parallel and perpendicular to the set slope.

The pressure switch 16 includes operating levers 6 for the boom 200, the stick 300, and the bucket 400.
It is attached to the pilot pipe for 8 via a selector 17 and the like, and is used to detect whether or not the operation levers 6, 8 are neutral. That is, when the operation levers 6 and 8 are in the neutral state, the output of the pressure switch 16 is turned off, and when the operation levers 6 and 8 are used, the output of the pressure switch 16 becomes O.
N. The neutral detection pressure switch 16 is also used for detecting abnormality of the pressure sensor 19 and switching between a manual / semi-automatic mode.

The resolver 20 is provided at a pivot (joint portion) of the boom 200 to the construction machine main body 100, which can monitor the posture of the boom 200, and functions as a first angle sensor for detecting the posture of the boom 200. The resolver 21 is provided at a pivotal connection (joint) of the stick 300 to the boom 200, which can monitor the posture of the stick 300, and functions as a second angle sensor that detects the posture of the stick 300. . Also, the resolver 22
A link mechanism pivoting portion that can monitor the attitude of the bucket 400 functions as a third angle sensor that detects the attitude of the bucket 400. These resolvers 20 to
At 22, an angle detecting means for detecting the posture of the arm mechanism based on the angle information is constituted.

The signal converter (conversion means) 26 converts the angle information obtained by the resolver 20 into telescopic displacement information of the boom cylinder 120, and converts the angle information obtained by the resolver 21 into telescopic displacement information of the stick cylinder 121. The angle information obtained by the conversion and the resolver 22 is converted to the bucket cylinder 12
2 which converts the information into expansion / contraction displacement information, that is, the resolver 20
To the corresponding cylinders 120 to
122, the signal converter 26 includes an input interface 26A that receives signals from the resolvers 20 to 22, and the resolvers 20 to 22.
22 corresponding to the angle information obtained at 22
Rook-up table 2 for storing telescopic displacement information of 22
A main processing unit (CPU) 26C that obtains telescopic displacement information of the cylinders 120 to 122 corresponding to the angle information obtained by the resolvers 20 to 22, and communicates the cylinder telescopic displacement information to the controller 1. , And an output interface 26D for transmitting cylinder expansion / contraction displacement information from a main processing unit (CPU) 26C.

By the way, the cylinders 120 corresponding to the angle information θbm, θst, θbk obtained by the resolvers 20 to 22 are used.
The expansion / contraction information λbm, λst, λbk of to 122 can be obtained by the following equation using the cosine theorem. ^{_{λbm = (L 101102 2 + L}} 101111 2 -2L 101102 · L 101111 cos (θbm + Axbm)) 1/2 ·· (1) λst = (L 103104 2 + L 104105 2 -2L 103104 · L 104105 cosθst) 1/2 ·· _{(2) λbk = (L 106107} 2 + L 107109 2 -2L 106107 · L 107109 cosθbk) 1/2 ·· (3) where, in the above equation, L _ij is a fixed length, Axbm represents fixed angle, of L The subscript ij has information between the nodes i and j.
For example, _L101102 represents the distance between the nodes 101 and 102. The node 101 is the origin of the xy coordinates (see FIG. 6).

Of course, each time the resolver 20 to 22 obtains the angle information θbm, θst, θbk, the above equation may be calculated by the calculating means (for example, the CPU 26C). In this case, the CPU 26C determines the cylinders 120 to 12 corresponding to the angle information from the angle information obtained by the resolvers 20 to 22.
This constitutes an operation means for obtaining the expansion / contraction displacement information by calculation.

The signal converted by the signal converter 26 is used not only for feedback control at the time of semi-automatic control but also for measuring coordinates for position and display of the tip of the bucket. Further, the tip position of the bucket in the semi-automatic system is calculated with one point of the upper swing body 100 of the hydraulic shovel as an origin. When the upper swing body 100 is inclined in the front linkage direction, the coordinate system on the control calculation is changed to the vehicle. It is necessary to rotate by the amount of the inclination. The tilt sensor 24 is used to correct the rotation of the coordinate system.

As described above, the electromagnetic proportional valves 3A to 3C control the hydraulic pressure supplied from the pilot pump 50 by the electric signal from the controller 1, and change the controlled hydraulic pressure to the switching valves 4A to 4C or the selector valves 18A to 18C. Through the main control valves 13, 14, 15 through
The main control valves 13, 1 are set so that the cylinder target speed is obtained.
The spool positions 4 and 15 are controlled. If the switching valves 4A to 4C are set to the manual mode, the cylinder can be controlled manually.

The stick merging adjustment proportional valve 11 adjusts the merging degree of the two pumps 51 and 52 in order to obtain an oil amount corresponding to the target cylinder speed. Further, an ON-OFF switch (a slope excavation switch) 9 is attached to the stick operation lever 8, and a semi-automatic mode is selected or deselected by operating the switch by an operator. When the semi-automatic mode is selected, the tip of the bucket can be moved linearly.

Further, the bucket operation lever 6 is turned on.
A -OFF switch (bucket automatic return start switch) 7 is attached, and when the operator turns on this switch 7, the bucket 400 can be automatically returned to a preset angle. The safety valve 5 is for interrupting the pilot pressure supplied to the electromagnetic proportional valves 3A to 3C, and only when the safety valve 5 is in the ON state, the pilot pressure is changed to the electromagnetic proportional valves 3A to 3C.
It is supplied to. Therefore, if there is any failure in semi-automatic control, this safety valve 5 is turned off.
By setting to the FF state, the automatic control of the linkage can be stopped immediately.

The rotation speed of the engine E varies depending on the position of the engine throttle set by the operator.
Further, even when the engine throttle is constant, the engine speed changes depending on the load. Pumps 50, 51, 52
Is directly connected to the engine E, and when the engine rotation speed changes, the pump discharge amount also changes. Therefore, even if the spool position of the main control valves 13, 14, 15 is constant, the cylinder speed is equal to the engine rotation speed. It changes according to the change. In order to correct this, an engine speed sensor 23 is attached. That is, when the engine speed is low, the target moving speed of the bucket tooth tip is reduced.

Monitor panel 10 with target slope angle setting device
(Hereinafter may be referred to as a monitor panel) is used as a setting device for a target slope angle α (see FIGS. 6 and 11) and a bucket return angle, and is also used to set the coordinates of the bucket tip 400 and the measured slope angle. Alternatively, it is also used as a display of the measured distance between the coordinates of two points. The monitor panel 10 is connected to the operation room 6 along with the operation levers 6 and 8.
00.

That is, in the system according to the present embodiment, the pressure sensor 1 is connected to the conventional pilot hydraulic line.
9 and the pressure switch 16 are incorporated, the operation amounts of the operation levers 6 and 8 are detected, and feedback control is performed using the resolvers 20, 21, and 22.
The configuration is such that independent multi-degree-of-freedom feed hack control can be performed for each of 121 and 122. Thereby, it is not necessary to add an oil device such as a pressure compensating valve. In addition, using the vehicle inclination angle sensor 24, the effects of the inclination of the upper revolving unit 100 are corrected, and the electromagnetic proportional valves 3A to 3C are driven by electric signals from the controller 1 to drive the cylinders 120, 121, and 122. It is also used. The manual / semi-automatic mode changeover switch 9 allows the operator to arbitrarily select a mode, and also allows a target slope angle to be set.

Next, the control algorithm of the semi-automatic system performed by the controller 1 will be described. The control algorithm of the semi-automatic control mode (excluding the bucket automatic return mode) performed by the controller 1 is as shown in FIG. Has become. That is, first, the moving speed and direction of the bucket tip 112 are determined by the target slope setting angle, the stick cylinder 121 and the boom cylinder 12.
0 is obtained from information on pilot oil pressure, vehicle inclination angle, and engine rotation speed that control 0. Next, the target speed of each cylinder 120, 121, 122 is calculated based on the information. At this time, information on the engine rotation speed is required when determining the upper limit of the cylinder speed.

As shown in FIGS. 3 and 4, the controller 1 includes independent control units 1A, 1B, and 1C for each of the cylinders 120, 121, and 122.
As shown in FIG. 4, they are configured as independent control feedback loops so that they do not interfere with each other. As shown in FIG. 5, the compensation configuration in the closed loop control (see FIG. 4) includes a feedback loop and a feed forward loop for displacement and speed, as shown in FIG. 5, for each of the control units 1A, 1B, and 1C (see FIGS. 3 and 4). It has a multi-degree of freedom configuration.

That is, when the target speed is given, regarding the feedback loop processing, a predetermined gain Kvp (reference numeral 6) is applied to the deviation between the target speed and the speed feedback information.
2) and the target speed are once integrated (see the integration element 61 in FIG. 5), and a predetermined gain Kpp is added to the deviation between the target speed integration information and the displacement feedback information.
(See reference numeral 63) and a process of multiplying the deviation between the target speed integral information and the displacement feedback information by a predetermined gain Kpi (see reference numeral 64) and further integrating (see reference numeral 66). As for the feedforward loop processing, processing is performed by a route that multiplies the target speed by a predetermined gain Kf (see reference numeral 65).

The above gains Kvp, Kpp, Kp
The values of i and Kf can be changed by the gain scheduler 70. In addition, the nonlinear removal table 7
1 is provided for removing nonlinearities of the electromagnetic proportional valves 3A to 3C, the main control valves 13 to 15, and the like. The processing using the nonlinear removal table 71 is performed by using a table lookup method. It is performed at high speed by a computer.

With such a configuration, when a slope excavation operation with a target slope angle α as shown in FIG. 11 is performed semi-automatically using a hydraulic excavator, the system according to the present invention employs a conventional manual control system. In comparison with the above, the semi-automatic control function as described above can be realized by an electro-hydraulic system that automatically adjusts the combined movement amount of the boom 200 and the stick 300 according to the excavation speed. That is, detection signals (including target slope angle setting information) from various sensors are input to the controller 1 mounted on the hydraulic excavator, and the controller 1 detects signals (signal converters 26) from these sensors. (Including detection signals from the resolvers 20 to 22 via the solenoid valves), the main control valves 13, 14, and 15 are controlled via the electromagnetic proportional valves 3A, 3B, and 3C.
The boom 200, the stick 300, and the bucket 400 are controlled so as to have a desired expansion / contraction displacement, and the above-described semi-automatic control is executed. In this semi-automatic control, first, the moving speed and direction of the bucket tip 112 are determined by the target slope setting angle, the stick cylinder 121
And a pilot hydraulic pressure for controlling the boom cylinder 120,
The target speed of each of the cylinders 120, 121, 122 is calculated based on the information of the vehicle inclination angle and the engine rotation speed. At this time, information on the engine rotational speed is required when determining the upper limit of the cylinder speed. In addition, the control is performed as an independent feedback loop for each of the cylinders 120, 121, and 122, and does not interfere with each other.

The setting of the target slope angle in this semi-automatic system is performed by a numerical value input method using a switch on the monitor panel 10, a two-point coordinate input method, and a bucket angle input method. Is set by a method of inputting a numerical value using a switch on the monitor panel 10 or a method of moving a bucket, and in each case, a known method is used.

The above-described semi-automatic control modes and their control methods are performed as follows based on the information obtained by converting the angle information detected by the resolvers 20 to 22 into the cylinder expansion / contraction displacement information by the signal converter 26. It is. First, in the bucket angle control mode, the length of the bucket cylinder 122 is controlled so that the angle (bucket angle) φ between the bucket 400 and the x-axis becomes constant at an arbitrary position. At this time, the bucket cylinder length λbk is determined when the boom cylinder length λbm, the stick cylinder length λst, and the angle φ are determined.

In the smoothing mode, the bucket angle φ
Is kept constant, the bucket tip 112 and the node 108 move in parallel. First, the case where the node 108 moves parallel to the x-axis (horizontal excavation) is as follows. That is, in this case, the coordinates of the node 108 in the linkage posture at which excavation starts are (x ₁₀₈ , y
_108), and obtains the cylinder length of the boom cylinder 120 and stick cylinder 121 in the linkage posture in this, the boom 200 so x ₁₀₈ to move horizontally
And the speed of the stick 300 are obtained. Note that node 108
Is determined by the operation amount of the stick operation lever 8.

When the parallel movement of the node 108 is considered, the coordinates of the node 108 after a short time Δt are (x ₁₀₈ + Δ
x, y ₁₀₈ ). Δx is a minute displacement determined by the moving speed. Therefore, by considering the Δx in x _108, the target boom and length of the stick cylinder after Δt is obtained. In the slope excavation mode, control may be performed in the same manner as in the smoothing mode, but the control is performed in consideration of the fact that the moving point is changed from the node 108 to the bucket tip position 112 and the bucket cylinder length is fixed. .

For the correction of the finishing inclination angle by the vehicle inclination sensor 24, the calculation of the front linkage position is performed in the xy coordinate system with the node 101 in FIG. 6 as the origin. Therefore, when the vehicle body tilts with respect to the xy plane, the xy coordinates rotate, and the target tilt angle with respect to the ground changes. In order to correct this, an inclination angle sensor 24 is attached to the vehicle. When the inclination angle sensor 24 detects that the vehicle body is rotating by β with respect to the xy plane, a value obtained by adding β is added. The correction may be made by correcting.

The prevention of deterioration of control accuracy by the engine speed sensor 23 is as follows. That is,
As for the correction of the target bucket tip speed, the target bucket tip speed is determined by the positions of the sticks and the boom operation levers 6, 8 and the engine rotation speed. Further, since the hydraulic pumps 51 and 52 are directly connected to the engine E, when the engine rotation speed is low, the pump discharge amount also decreases, and the cylinder speed decreases. Therefore, the engine rotation speed is detected, and the target bucket tip speed is calculated so as to match the change in the pump discharge amount.

For the correction of the maximum value of the target cylinder speed, if the target cylinder speed changes depending on the attitude of the linkage and the target slope angle, and if the pump discharge rate decreases as the engine speed decreases, A correction is made taking into account that the maximum cylinder speed also needs to be reduced. When the target cylinder speed exceeds the maximum cylinder speed, the target bucket tip speed is reduced,
Make sure that the target cylinder speed does not exceed the maximum cylinder speed.

The various control modes and their control methods have been described above, but all of them are methods based on cylinder expansion / contraction displacement information, and the control contents by this method are publicly known. That is, in the system according to the present embodiment, after the angle information is detected by the resolvers 20 to 22,
Since the angle information is converted into cylinder expansion / contraction displacement information by the signal converter 26, a known control method can be used thereafter.

In this way, various controls are performed by the controller 1. In the system according to the present embodiment, the angle information signals detected by the resolvers 20 to 22 are
Since the signal is converted into cylinder displacement information by the signal converter 26 and input to the controller 1, an expensive stroke for detecting each expansion and contraction displacement of the boom 200, the stick 300, and the cylinder for the bucket 400 as in the related art is used. Even without using a sensor, it is possible to execute control using the cylinder expansion and contraction displacement used in the conventional control system.
As a result, while keeping the cost low, the bucket 400
It is possible to provide a system that can accurately and stably control the position and posture of the camera.

Further, since the feedback control loop is independent for each of the cylinders 120, 121, and 122 and the control algorithm is a multi-free control of displacement, speed and feed forward, the control system can be simplified.
Since the non-linearity of the hydraulic equipment can be linearized at high speed by a table look-up method, it also contributes to an improvement in control accuracy.

Further, since the influence of the vehicle inclination is corrected by the vehicle inclination sensor 24 or the engine rotational speed is read in, the deterioration of the control accuracy due to the change in the position of the engine throttle and the load is corrected. Contributes to the realization of In addition, since maintenance such as gain adjustment can be performed using the external terminal 2, there is an advantage that adjustment and the like are easy.

Further, the amount of operation of the operating levers 7 and 8 is obtained from the change in the pilot pressure using the pressure sensor 19 and the like. Further, since the conventional open center valve hydraulic system is used as it is, the pressure compensating valve and the like are used. In addition to the advantage that no additional is required, the monitor 10 with the target slope angle setting device
Can also display the bucket tip coordinates in real time. Further, the configuration using the safety valve 5 can also prevent a system abnormal operation when the system is abnormal.

The present invention is not limited to the above-described embodiment, but can be implemented in various modifications without departing from the spirit and scope of the present invention.

[0062]

As described above in detail, according to the control device for a construction machine of the present invention, the angle detecting means for detecting the posture of the arm mechanism by the angle information and the angle information obtained by the angle detecting means are used. Conversion means for converting into expansion and contraction displacement information of the corresponding cylinder type actuator; and control means for controlling the cylinder type actuator to have a predetermined expansion and contraction displacement based on the expansion and contraction displacement information of the cylinder type actuator converted by the conversion means. Since it is provided, the angle information detected by the angle detection means is converted into expansion / contraction displacement information by the conversion means and input to the control means, thereby detecting the expansion / contraction displacement of each actuator as in the related art. It is possible to execute control using the expansion and contraction displacement of the actuator used in the conventional control system without using an expensive stroke sensor for performing Can. As a result, it is possible to provide a system capable of accurately and stably controlling the position and orientation of the bucket while keeping costs low.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a hydraulic shovel equipped with a control device according to an embodiment of the present invention.

FIG. 2 is a diagram schematically showing a control system configuration according to an embodiment of the present invention.

FIG. 3 is a diagram schematically showing a control system configuration of a control device according to an embodiment of the present invention.

FIG. 4 is a diagram showing an overall configuration of a control system according to an embodiment of the present invention.

FIG. 5 is a main part control block diagram according to the embodiment of the present invention;

FIG. 6 is a schematic view of an operating portion of the excavator according to the present invention.

FIG. 7 is a schematic view showing the operation of the excavator according to the present invention.

FIG. 8 is a schematic view showing the operation of the excavator according to the present invention.

FIG. 9 is a schematic view showing the operation of the excavator according to the present invention.

FIG. 10 is a schematic view showing the operation of the excavator according to the present invention.

FIG. 11 is a schematic view showing the operation of the hydraulic shovel according to the present invention.

FIG. 12 is a diagram showing a schematic configuration of a conventional hydraulic excavator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Controller (control means) 1A-1C control part 2 External terminal 3A-3C Electromagnetic proportional valve 4A-4C Electromagnetic switching valve 5 Safety valve 6 Boom, bucket operation lever 7 Bucket automatic return start switch 8 Stick operation lever 9 Slope excavation switch 10 Monitor panel with target slope angle setting device 11 Stick merging proportional valve 13 Main control valve for boom 14 Main control valve for stick 15 Main control valve for bucket 16 Pressure switch 17 Selector valve (for operation lever) 18 Selector valve (manual / semi-automatic) 19) Pressure sensor 20 Resolver for boom cylinder (first angle sensor) 21 Resolver for stick cylinder (second angle sensor) 22 Resolver for bucket cylinder (third angle sensor) 23 Engine speed sensor 24 Tilt angle sensor 26 Signal Converter (change 26A Input interface 26B Memory 26B-1 Lookup table 26C Main processing unit (CPU) 26D Output interface 27 Engine pump controller 28A, 28B Pressure sensor 50 Pilot pump 51, 52 Pump 100 Upper rotating body (construction machine body) 120 Boom cylinder (cylinder type actuator) 121 Stick cylinder (cylinder type actuator) 122 Bucket cylinder (cylinder type actuator) 130 Link mechanism 200 Boom 300 Stick 400 Bucket 500 Lower traveling body 500A Infinite rail section 600 Driving operation room E Engine

Claims (7)

[Claims] An articulated type having a construction machine main body, and at least one pair of arm members connected to each other via a joint portion while having a working member at one end pivotally connected to the construction machine main body at the other end side. An arm mechanism; a cylinder-type actuator mechanism having a plurality of cylinder-type actuators for driving the arm mechanism by performing an expansion / contraction operation; angle detection means for detecting a posture of the arm mechanism with angle information; Conversion means for converting the obtained angle information into corresponding expansion / contraction displacement information of the cylinder type actuator; and, based on the expansion / contraction information of the cylinder type actuator converted by the conversion means, the cylinder type extension / contraction A control device for a construction machine, comprising: control means for controlling a displacement. 2. An articulated arm mechanism comprising: a boom having one end rotatably connected to the construction machine body; and one end rotatable with respect to the boom via the joint. The work member is configured to include a stick to be connected, and the working member is rotatably connected to the stick at one end through a joint, and the tip excavates the ground and can accommodate earth and sand therein. The control device for a construction machine according to claim 1, wherein the control device is configured as a simple bucket. 3. The cylinder type actuator mechanism is interposed between the construction machine main body and the boom, and rotates the boom with respect to the construction machine main body by expanding and contracting a distance between ends. A boom hydraulic cylinder, a stick hydraulic cylinder interposed between the boom and the stick, and rotating the stick with respect to the boom as the distance between the ends expands and contracts; 3. A bucket hydraulic cylinder, which is interposed between the bucket and a bucket and is configured to rotate the bucket with respect to a stick by expanding and contracting the distance between the ends. Equipment for construction machinery. 4. An angle detecting means comprising: a first angle sensor for detecting a posture of the boom; a second angle sensor for detecting a posture of the stick; and a third angle sensor for detecting a posture of the bucket. 3. The control device for a construction machine according to claim 2, wherein the control device is provided. 5. The apparatus according to claim 1, wherein said conversion means includes an operation means for calculating, based on the angle information obtained by said angle detection means, telescopic displacement information of said cylinder type actuator corresponding to said angle information. The control device for a construction machine according to claim 1. 6. The apparatus according to claim 1, wherein said conversion means includes storage means for storing information on the expansion / contraction displacement of said cylinder type actuator corresponding to the angle information obtained by said angle detection means. Equipment for construction machinery. 7. The conversion means converts the angle information obtained by the first angle sensor into expansion and contraction displacement information of the boom hydraulic cylinder, and converts the angle information obtained by the second angle sensor to the stick hydraulic cylinder. 4. The construction machine according to claim 3, wherein said construction machine is configured to convert the angle information obtained by said third angle sensor into said telescopic displacement information of said bucket hydraulic cylinder. Control device.