JPH101968A - Automatic locus controller for hydraulic construction equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic locus controller capable of being smoothly transferred to the automatic control of a desired operation locus by the nomal operation of a control lever and having extremely excelllent operationability. SOLUTION: The coordinates (x, y) of the cutting edge C of a bucket 18 are arithmetically operated at all times on the basis of the information of the rotational angles of a boom 16, an arm 17 and the bucket 18 detected by each rotational-angle sensor 12-14 for a working machine in a controller 11. When the coordinates (x, y) of the cutting edge C are placed in a specified leveling- operation start-place region and pilot pressure Pb on the boom and arm-draw pilot pressure Pa detected by the pressure sensors 6, 7 and these time changes are decided to be brought to the state of initial-motion operation at the time of leveling-operation start, initial-motion transfer operation automatic locus control for smooth transfer to horizontal-leveling operation automatic locus control is conducted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of hydraulic construction machines such as hydraulic shovels, and more particularly to the technical field of automatic trajectory control for automatically controlling the movement trajectory of a work body such as a bucket to a desired surface. Belong to.

[0002]

2. Description of the Related Art The work contents of construction machines, for example, hydraulic excavators are diverse, but typical work is excavation work,
There are loading / discharging work, transport work, leveling work, etc. Of these tasks, leveling is a very frequent task,
Moreover, high working accuracy is required. FIG. 21 is an explanatory diagram showing a state in which a hydraulic shovel is used for leveling work. As shown in the figure, in the leveling work, after the bucket 18 has reached a sufficiently far position as shown by the broken line, the arm 17 is rotated so as to be pulled toward the front side, and the boom 16 is fast at the beginning and rearward. in by performing the combined operation of raising slowly, with the cutting edge is moved along a plane parallel to the reference plane S ₀ or reference plane S ₀ the bucket 18, the bucket 18
The work referred to herein is the work of scraping and leveling the earth and sand abutting on the blade edge to form a flat reference plane S ₀ or a plane parallel to the reference plane S ₀ .

A rigid columnar body of a work machine, for example, a boom 16
When the arm 17 and the arm 17 are operated independently, the pivoting movement about the pivot of the pivoting portion of the boom 16 with respect to the excavator body and the pivoting portion of the arm 17 with respect to the boom 16 as shown by arrows A and B, respectively. Then, the blade edge of the bucket 18 draws an arc locus. As described above, the boom 16 and the arm 1 that originally draw an arc trajectory on the cutting edge of the bucket 18 are used.
By performing a combined operation of the rigid columnar members such as 7, a leveling operation for drawing a straight line or a plane locus on the cutting edge of the bucket 18 is performed by independently operating different operation rods for operating the movements of the boom 16 and the arm 17 respectively. Since this work can only be achieved by operating with a well-balanced operation amount, considerable skill was required to achieve an excellent work balance.

If the operator is inexperienced, he or she may have performed a leveling operation to make a flat surface, but rather may make a large uneven surface. FIG. 22 is an explanatory diagram showing an example of an operation when an unskilled operator operates a hydraulic excavator to perform leveling work. In the illustrated leveling operation, the movement of the boom 16 is a rotating operation that rises against its own weight, whereas the movement of the arm 17 is a rotating operation that descends in the same direction as its own weight. As shown in FIG. 22, the movement of the arm 17 becomes too fast,
It will bite into the reference plane S ₀ edge of. Then, the operator operates the operating rod so as to raise the boom 16 rapidly in a hurry.
Blade 8 would jump out upward from the reference plane S _0. As a result of repeating such a rough operation, a large uneven locus shown in FIG. 22 is formed.

[0005] In addition, in order to discharge the earth and sand scooped up by the bucket 18 to a predetermined place, there is a case where the earth and sand is conveyed by moving the bucket 18 almost horizontally while keeping the posture of the bucket 18 constant. FIG. 23 is an explanatory view showing a state in which the desired earth and sand transfer work has been executed, and FIG. 24 is an explanatory diagram showing a state in which the execution of the desired earth and sand transfer work has failed. In this case, the boom 16 hardly moves, but the arm 17 and the bucket 18 rotate and the revolving structure rotates.
Since two simultaneous composite operations are required, the operator is required to perform complicated and delicate operation of the operation stick. In order to keep the posture of the bucket 18 constant, the holding angle of the bucket 18 with respect to the arm 17 slightly changes depending on the moving position. Therefore, if the user carelessly tilts the posture of the bucket 18, as shown in FIG. It may be zero on the way.

As described above, a number of attempts have been conventionally made to precisely perform a leveling operation and a conveying operation that require a high level of manual operation by computer control. For example, some of them are listed in JP-A-58-36135, JP-A-55-30038, JP-B-3-13378, and JP-B-3-2854.
There is an invention disclosed in Japanese Patent Publication No. 4 and the like.

[0007]

In the above prior art, when performing excavation work or leveling work along any plane, numerical input by operating a control panel for setting a work area and a work surface, Target setting by inputting position setting while maintaining the work machine at the desired operating position, inputting a work start command at the start of automatic work and a work end command at the end of automatic work, or operating a correction operation rod Operations to set the amount of deviation from the surface must be performed, and in many cases these operations are performed by interrupting the heavy excavation work, earth dumping work, suspended load work, etc. Therefore, the operation feeling for the machine of the operator is significantly impaired, and these input operations, which are completely different from the operation of the operation rod for normal work, impair the continuity of the operation, making the operator distracting and annoying. To Will be occupied ze, much trouble to the hydraulic excavator, it is often actually be equipped with an automatic trajectory control device is not used, as it is the automatic control system for a construction machine not be said to be very practical.

Further, as described above, when the leveling work is started, the retracting operation of the arm has a cooperative relationship with the rotational moment due to the weight of the arm, so that even if the operation of the operating rod for the arm is slightly accelerated, the tip of the arm is slightly advanced. Immediately lowers the bucket blade edge, detects the operation of the arm operation rod, raises the boom by the automatic trajectory control device following the movement of the arm, and performs the leveling work to move the bucket blade edge along a predetermined plane. Even if such control is performed, the ascending operation of the boom cannot keep up with the descending operation of the arm due to the operation delay of the hydraulic control mechanism and the locus of the blade edge of the bucket 18 is as shown in FIG. 18 cutting edge of becomes trajectory that would bite into the reference plane S _0, the result of the trajectory control by subsequent automatic trajectory control device, is intended to compensate for the working path by unskilled operator,殆Problem that the great difference not work locus only not be obtained occurs.

To prevent the occurrence of such a problem,
By carefully operating the operating rod for the arm, it is possible to easily follow the movement of the boom with the movement of the arm, but this will reduce the work efficiency, and thus also reduce the practical value of the automatic trajectory control. I will end up. Furthermore, once the automatic trajectory control is started, the working machine is automatically operated,
Even if the work trajectory of the work realized by the automatic trajectory control deviates from the one intended by the operator due to the error of various detection devices or erroneous setting of the target surface, the automatic trajectory control is required to correct it. And the target plane must be set again, which is not only a troublesome operation in itself, but also the work trajectory of the work body can be made to match the operator's intention by resetting. Was actually difficult.

The present invention solves such a problem in the prior art, and does not require a special operation information input operation or an unnecessarily careful operation of the operation stick, and only the normal operation of the operation stick is performed. An operation that can smoothly shift to the automatic control of the desired work locus, and when the work locus is not the desired one, the work locus can be corrected without any discomfort by the same operation as the normal manual correction operation. It is an object of the present invention to provide an automatic trajectory control device for a hydraulic construction machine that is extremely excellent in performance.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention monitors an operation state of an operation rod operated by an operator, and controls an operation amount of the operation rod and a change in an operation amount of the operation rod. It is determined whether the amount is within a predetermined range set in advance, and when the determination result is correct, the operation state is determined to be an initial operation for drawing a predetermined standard movement locus. Then, the hydraulic drive mechanism is controlled to start automatic trajectory control that automatically draws a standard movement trajectory on the work body, and then the change amount of the operation amount of the operation rod is monitored and the change of the operation amount is performed. When it is judged that the absolute value of the quantity is larger than the predetermined value,
It is determined that the operator intends to correct the trajectory of the automatic trajectory control, and the automatic trajectory correction control that automatically corrects the initial standard movement trajectory according to the change amount of the operation amount is performed and the operation is performed. The operation state of the operation stick is monitored to determine whether the operation amount of the operation stick and the change amount of the operation amount have exceeded another predetermined range set in advance, and the determination result is correct. When it is determined that the operation state of the operating rod by the operator is not intended to continue the initial standard movement trajectory control operation, the control is performed so as to end the initial standard movement trajectory automatic control. is there.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Automatic trajectory control is usually performed by a microcomputer mounted on a construction machine. In the present invention, the construction machine is typically a hydraulic excavator, in which case the work body is a bucket. A typical track forming operation in a hydraulic excavator is leveling work on the ground. In the following explanation, the explanation will be given with the automatic trajectory control of the leveling work of the hydraulic excavator, which is the above-mentioned typical example, in mind. The same applies to the trajectory control.

As a means for transmitting the operating direction and the operating amount of the operated operating rod, which is the operating information of the operating rod, a pilot control system in which pilot oil is interposed and an electrical control system in which electric-mechanical conversion is performed via an electrical signal However, since the control form is essentially the same regardless of which transmission means is used and the pilot control system is generally used, the pilot control system will be taken into consideration in the following description. Therefore, in this case, the operation amount of the operation rod is converted into the pressure of the pilot oil flowing out of the pilot valve connected to the operation rod, that is, the pilot pressure is converted into the pressure value of the electric signal detected by the pressure sensor. Based on the pilot pressure converted to, the automatic trajectory control is a system that reduces the pilot pressure transmitted to the pilot receiving portion of the direction switching valve that switches the direction and flow rate of the hydraulic oil supplied to the actuator. The control of the pilot pressure for the pilot receiving portion of the direction switching valve is the current control for the electromagnetic pressure reducing valve directly connected to the pilot pump or the electromagnetic pressure reducing valve directly connected to the pilot valve connected to the operating rod.

Generally, the position and speed of the working body must be detected in order to perform automatic trajectory control. The position of the working body is determined by detecting the rotation angle of the joint portion of the rigid columnar body of the working machine. The relative angle of each rigid columnar body is detected by the moving angle sensor, and the three-dimensional coordinates of the working body can be easily calculated by the microcomputer by well-known coordinate conversion based on the detected relative angle. In addition, predetermined state information where the operation state of the operation rod should be a prerequisite for starting the standard trajectory automatic control, whether the operation state of the operation rod deviates from the standard trajectory control, and the operation Reference information, which is a basis for determining whether the operation state of the rod should stop the trajectory control operation, is stored in advance in the memory of the microcomputer. Next, the outline of the basic operation of the present invention will be described. FIG. 2 and FIG. 3 are operation conceptual diagrams for explaining the outline of the operation of the automatic trajectory control. In the automatic trajectory control according to the present invention, a general work by a normal manual operation and a standard work automatic trajectory control are performed in a form that can be executed without being clearly distinguished by the operator.

As shown in FIG. 2, it is determined whether or not to start the standard work automatic trajectory control while the general work by the normal manual operation is being performed (S1) (S2). If the determination result is correct, the standard work automatic trajectory control is executed (S
3) If the result of the determination in step S2 is negative, normal ordinary work is continued. While executing the standard work automatic trajectory control, it is always determined whether or not the standard work automatic trajectory control is stopped (S4). If the judgment result is correct, the standard work automatic trajectory control is stopped, and the control returns to the general work control by the normal manual operation in step S1. If the result of the determination in step S4 is negative, the process proceeds to step S5 in FIG. 3 to determine whether or not to correct the work locus of the standard work. If that is the case,
That is, when it is determined that the operator has performed an operation intended to correct the trajectory of the standard work, the standard work trajectory correction control for changing the trajectory of the standard work is executed (S6). If the determination result in step S5 is negative, the procedure returns to step S3 to continue the standard work automatic trajectory control.

As described above, in the present invention, when the standard work start condition determined in step S2 or the standard work stop condition determined in step S4 is satisfied, the normal general manual operation work control of step S1 to the step S3 is performed. To the standard work automatic trajectory control, from the standard work automatic trajectory control of step S3 to the procedure S1
Can be switched to the normal general manual operation work control at any time, and if the standard work trajectory correction condition is satisfied in step S5,
After automatically changing the trajectory of the standard work, the procedure returns to the standard work automatic trajectory control in step S3, which is greatly different from the conventional case where these work controls are independently processed.

That is, while the control of the general work is being performed, the contents of the operation of the operator are checked, and it is determined whether the operation is intended for the general work or the standard work. When it is determined that the standard work is intended, the standard work automatic trajectory control is started immediately, and the operation of the actuator is performed so that the trajectory of the standard work by the manual operation of the operator becomes the trajectory intended by the operator. When it is determined that an operation intended to stop the standard work has been performed while the standard work automatic trajectory control is being performed, the standard work automatic control is immediately performed. When the control of the trajectory is stopped and the control is returned to the control of the general work in which the control according to the manual operation of the operator is faithfully performed, and it is determined that the operation intended to correct the trajectory of the standard work is performed, Automatically It is obtained so as to change the trajectory of the quasi-work.

Next, the standard work start condition [A] and the standard work stop condition [B] determined in steps S2 and S4 will be described. In the following description, the case of performing a leveling operation to form a planar work forming surface, which is the most frequent standard operation and can be expected to improve the operation efficiency by automatic trajectory control, is described. The same can be applied to the work. First, the standard work starting condition [A] will be described. As described above, the standard work start condition [A] is specifically a standard work start operation range condition that the operation state of the operation rod of the operator is within a range in which it can be determined that the standard work start is intended.

First, the standard work start operation range condition [A] will be described. The standard operation start operation range condition [A] is a condition in which the initial operation state at the start of the leveling operation by a large number of operators is checked and statistically processed, and the standard operation start frequency is in a large range. FIG. 4 is an explanatory diagram showing specific contents of the leveling work start operation range condition. Results of the investigation by the present inventors, leveling work start operation range condition [A _L] further three operating range condition [A _L alpha], [A
It was found that it can be divided into _L β] and [A _L γ]. That is,
These three operating range conditions [A _L α], [A _L β], [A _L α]
_L γ] is as follows. [A _L α]; when the operator increases the operation amount at a moderate speed from a state in which the operator operates the arm and the operating rod of the boom in the neutral position or slightly raises the boom and pulls the arm, [A _L β] After the operator operates the operating rod of the arm in the arm pulling direction with a moderate operating amount and then maintains or slightly changes the operating amount, and moves the operating rod of the boom in the neutral position or slightly in the boom raising direction from the neutral position. When the operation amount is increased at a moderate speed from the state where the operation is performed, [A _L γ]: After the operator operates the operation stick of the boom with the medium operation amount in the boom raising direction, the operation amount is increased. Is maintained or slightly changed, and when the operation amount is increased at a moderate speed from a state in which the operation rod of the arm is slightly operated in the arm pulling direction from the neutral position or the neutral position, the symbol in FIG. (A), (b), c) Each aforementioned operating range condition [A _L alpha], [A _L beta],
It corresponds to [A _L γ].

In the operation range condition [A _L α] of (a), since the amount of operation in the boom raising and arm pulling directions at the time of initial movement is 0 or slightly, as shown in the attention area (A), Reference plane S on which initial movement position and linear trajectory control are performed
The distance between the ₀ is short, leveling work automatic trajectory control after moves in a linear path control along quickly reference plane S _0.
In the operation range condition [A _L β] of (b), the amount of operation in the arm pulling direction at the time of initial movement is medium, and the amount of operation is almost maintained, and the amount of operation in the boom raising direction at initial movement is 0 or slight. , as shown in the noted range (ii), the cutting edge of the bucket after descending by a certain distance Derutaeichibeta, moves in a linear path control along the reference plane S _0. In the operation range condition [A _L γ] of (c), the amount of operation in the boom raising direction at the time of initial movement is medium, and the amount of operation is almost maintained, and the amount of operation in the arm pulling direction at initial movement is 0 or small. As shown in the attention area (U), the blade edge of the bucket once rises, and after a certain distance ΔHγ is lowered by the automatic leveling work automatic path control, the straight path control along the reference plane S ₀ is performed. To do.

[0021] Thus, boom raising or arm pulling direction of the operation amount at greater than moderate during initial is will not satisfy the leveling work start operation range condition [A _L], it has a large inertia When moving the rigid columnar body of the work machine at high speed, for example, when performing an excavation work operation,
In general, it is theoretically extremely difficult to perform an accurate bucket trajectory forming operation by switching to a linear trajectory movement along a reference plane S _{0 in} which the moving direction of the bucket is different. It is almost impossible to do.

On the other hand, it does not satisfy even leveling work start operation range condition when the operation amount of boom raising and arm pulling direction during initial were both 0 or small value [A _L], in this case Since the boom and arm of the work machine are moved at a slow speed, even an inexperienced operator can perform sufficiently accurate leveling work, and there is little need to dare to perform automatic leveling work automatic trajectory control Therefore, it is excluded from the leveling work start operation range condition [A _L]. Therefore, when the automatic trajectory control of the leveling work, which is a typical example of the standard work, is performed according to the present invention, the operating states of the operating rod of the operator are as shown in FIGS. 4 (a), 4 (b) and 4 (c). operating range conditions shown [a _L alpha], [a _L beta], when satisfying [a _L gamma], are satisfied leveling task starting condition [a _L] is determined conceptual steps S2 of the automatic trajectory control in FIG. 2 As a result, the automatic leveling work automatic trajectory control is executed.

Next, the standard work stop condition [B] will be described. In the setting of the leveling work stop condition [B _L ],
The operating state of the operation stick during the execution of the leveling operation by a large number of operators is checked, and the operation frequency is extremely low during the execution of the leveling operation.
Operation conditions [B _L α], [B
_L β] and [B _L γ]. The contents of the operation conditions [ _BL α], [ _BL β], and [ _BL γ] for stopping the leveling operation are as follows. [B _L α]: When the operator operates the operation rod with a large operation amount in the boom raising direction, [B _L β]: The operator returns the operation rod from the operation state in the boom raising or arm pulling direction to the neutral position. When operated, [B _L γ]; when the operator increases or decreases the operating rod at a high speed, these operating conditions for stopping the leveling operation [B _L α], [B _L γ], [B _L γ]
_When any one of [ _L β] and [B _L γ] is satisfied, the leveling operation automatic trajectory control is immediately stopped, and the control of the general operation (S1) that performs the control faithfully according to the manual operation of the operator. ) Return to. Next, leveling work trajectory compensation condition content of [C _L] is similar to the content of the leveling work stopped operating conditions [B _L gamma], but the limit value of the decreasing speed of the joystick is leveling work stopped operating conditions [B
_L γ].

In this way, the operator finishes the leveling work by always determining whether or not the leveling work can be stopped in the conceptual procedure S4 of the automatic level control of FIG. 2 during execution of the leveling work automatic locus control. , When the operating rod is operated to shift to another work, not only can the automatic trajectory control of the leveling work be quickly terminated, but also the operating state of the operating rod is leveled against the operator's intention. Even if it is determined that the start operation range condition [ _AL ] is satisfied and the smoothing work automatic trajectory control is executed, the operation state of the operating rod by the operator thereafter satisfies the smoothing work stop condition [ _BL ]. Thus, the automatic trajectory control of the leveling operation can be immediately terminated, and the control can be returned to the control (S1) of the general operation. Regarding other standard work start operation range conditions [A] and standard work stop conditions [B], the conditions can be set in exactly the same manner, although the specific condition range is different, and the determination of whether or not each condition is satisfied is also exactly the same. Can be done.
Hereinafter, an embodiment in which the present invention is applied to automatic trajectory control of a hydraulic excavator for leveling work will be described in detail with reference to the drawings.

[0025]

FIG. 1 is a hydraulic control circuit diagram according to an embodiment of the present invention. In the figure, 1 is a hydraulic control valve including a boom directional switching valve and an arm directional switching valve, 2 is a high pressure selection valve, and 3 is a boom solenoid that reduces the hydraulic pressure of pilot oil flowing out from a boom pilot valve described later. The (proportional) pressure reducing valve 4 reduces the oil pressure of the pilot oil discharged from the pilot pump described later, and a complementary pressure generating electromagnetic (proportional) pressure reducing valve for generating a complementary pilot pressure for complementing the boom raising pilot pressure. An arm pull electromagnetic (proportional) pressure reducing valve for reducing the hydraulic pressure of pilot oil flowing out from an arm pull pilot valve, which will be described later, 6 is a boom pressure sensor for detecting the hydraulic pressure of pilot oil flowing out of the boom pilot valve, 7
Is an arm pulling pressure sensor for detecting the hydraulic pressure of pilot oil flowing out of the arm pulling pilot valve, 8 is a pilot pump serving as a supply source of pilot oil, 9 is a boom from which pilot oil flows out according to the operation amount during the boom raising operation. The upper pilot valve, 9a is a boom operation rod, 10 is an arm pull pilot valve through which the pilot oil flows out according to the amount of operation when the arm is retracted, 10a is an arm control rod, and 11 is a microcomputer. This is a control device that executes automatic work trajectory control.

[0026] In the components of the hydraulic excavator body and the working machine, 12 provided to the rotation fulcrum of the boom 16 in the hydraulic excavator body to be described later, the rotation angle of the boom 16 theta _b
Boom rotation angle sensor for detecting
The arm rotation angle sensor is provided at the rotation fulcrum of the arm 17 at the tip of the arm 17 and detects the rotation angle θ _a of the arm 17, and 14 is provided at the rotation fulcrum of the bucket 18 at the tip of the arm 17. A bucket rotation angle sensor that detects the rotation angle θ _bu of the bucket 18, 15 is a hydraulic excavator body, and 19 is an oil discharge flow rate detector that detects the discharge flow rate Q _max of a hydraulic pump (not shown) that is a supply source of hydraulic oil. It is.
The same parts as those in the conventional example are denoted by the same reference numerals, and redundant description will be omitted.

In the automatic trajectory control of the leveling operation, since the bucket 18 merely adopts a well-known posture control method for keeping the posture constant with respect to the reference plane, its control circuit is not shown. Further, the boom directional switching valve and the arm directional switching valve included in the hydraulic control valve 1 have a specific configuration, and the hydraulic circuits that connect the boom 16 and the boom cylinder, and the arm 17 and the arm cylinder, respectively, have no new features. Since it is not included and only makes the figure complicated, the illustration is also omitted.

As shown in the figure, the control device 11 includes a boom rotation angle sensor 12, an arm rotation angle sensor 13,
The rotation angle θ _{b of} the boom 16, the arm 17, and the bucket 18 detected by the bucket rotation angle sensor 14, respectively,
The coordinates (x, y) of the cutting edge C of the bucket 18 are calculated based on the information of θ _a and θ _bu , and the coordinates (x, y) of the cutting edge C are calculated.
, The boom pilot pressure p _b and the arm pull pilot pressure p _a detected by the boom pressure sensor 6 and the arm pull pressure sensor 7, respectively, and the oil discharge flow rate detector 19
There based on the discharge flow rate Q _max of the hydraulic pump detected, respectively control current to the boom on the solenoid pressure reducing valve 3, the complementary pressure generating solenoid pressure reducing valve 4 and the arm pulling solenoid pressure reducing valve 5 e _b, e _c, e
and outputting _a, hydraulic squeezing pressure SV _b of pilot oil flowing out of the electromagnetic pressure reducing valves 3 to 5, SV _c, by controlling the pilot pressure so as not to exceed the SV _a, flows into the hydraulic control valve 1 The automatic leveling work control is performed to control the hydraulic pressure of the pilot oil, that is, the boom actual pilot pressure p _br and the arm pull actual pilot pressure p _ar , respectively.

The program for automatic leveling work trajectory control is stored in a ROM built in the control device 11. Further, in order to simplify the explanation, the hydraulic excavator is on a level ground, and the leveling reference plane S for performing automatic leveling work trajectory control is provided.
_{A case} where the horizontal tracing work automatic trajectory control in which ₀ is a plane parallel to the horizontal plane will be described.However, the case where the hydraulic excavator is on the ground inclined with respect to the horizontal plane and in an inclined posture, Even when the surface S ₀ is not parallel to the ground, the method described in the present embodiment can be similarly applied, and by performing well-known coordinate conversion on the arithmetic expression described later, the arithmetic expression in that case can be easily obtained.

As will be described later, the control device 11 controls the rotation angles θ _b , θ _a and θ _{bu of} the boom 16, the arm 17 and the bucket 18 detected by the rotation angle sensors 12 to 14 of the working machine.
Of the cutting edge C of the bucket 18 (x,
y) is calculated to determine whether the coordinates (x, y) of the cutting edge C are within a predetermined leveling work start position region R, and the boom pressure sensor 6 and the arm pulling pressure sensor 7 respectively monitoring the values and their rate of change of the detected boom on the pilot pressure p _b and the arm pulling pilot pressure p _a, it is determined whether each is in the leveling work start operation region set in advance. If both are determined to be correct, the operator manually operates the boom operating rod 9a and the arm operating rod 10a to level the work, that is, while keeping the bucket 18 in a constant posture, the hydraulic excavator side. The leveling work of the bucket 18 is performed so that the operation command of the horizontal leveling work that pulls the object horizontally can be corrected to smoothly move to the horizontal leveling work automatic path control (II) that reliably draws a horizontal path. performing automatic trajectory control start position initial migration automatic trajectory control horizontal pulling leveling work moved smoothly on a horizontal reference plane S ₀ to be performed from (I).

Furthermore, leveling work controller 11 even after the automatic trajectory control is started by monitors the values and their rate of change of the pilot pressure p _b and the arm pulling pilot pressure p _a boom, that either Is outside the leveling work continuation operation area, and if it is determined that it is out of the leveling work continuation operation area, the content of the manual operation of the operating rods 9a, 10a by the operator is the trajectory of horizontal pulling. The horizontal pulling position correction control (III) that smoothly shifts the movement trajectory of the bucket 18 to a new horizontal pulling trajectory parallel to the original trajectory is performed, and monitoring the values and their rate of change of the pilot pressure p _b and the arm pulling pilot pressure p _a, it is determined whether or intended to stop the leveling work automatic trajectory control, if the result of the determination is Yea For horizontal leveling work Stops the trajectory control (II), the boom operation of the operator rod 9a and arm control lever 10a
The automatic trajectory control (IV) for canceling the horizontal smoothing operation to smoothly return to the control of the general operation by the manual operation of the user is performed. In addition,
The automatic trajectory control (II) of the horizontal smoothing operation during the automatic trajectory control of the leveling operation is equivalent to the automatic trajectory control of the horizontal leveling operation proposed in the conventional example, and therefore, detailed description is omitted in this specification. I do.

Next, the operation of this embodiment will be described. 5 to 8 are flowcharts of the automatic leveling work automatic trajectory control according to the present embodiment. The operation of the automatic leveling work automatic trajectory control will be described with reference to these drawings. When the leveling operation automatic trajectory control mode is selected, the leveling operation automatic control is started.
However, even if the automatic leveling work automatic trajectory control mode is selected, the operator manually operates the boom operation rod 9a and the arm operation rod 10a to perform general work other than leveling work as normal manual operation work. It can be performed with exactly the same operation. That is, the procedure S11 is a processing procedure that allows the operator to perform a normal general operation other than the leveling operation by an operation that is completely the same as the operation by the manual operation of the normal boom operation rod 9a and the arm operation rod 10a. Shows.

That is, when the operator performs normal general work
Means that the control device 11 controls the boom-mounted electromagnetic pressure reducing valve 3 and the complementary pressure
Output to the electromagnetic pressure reducing valve 4 and the arm pulling electromagnetic pressure reducing valve 5, respectively.
Control current e_b, E_c, E_aValue of each solenoid pressure reducing valve
3 to 5 throttle pressure SV_b, SV _c, SV_aAre each
Pilot pressure on boom detected by pressure sensor 6 on boom
p_bAdditional pressure Δp_bPlus 0, and
Arm pulling pilot pressure detected by the arm pulling pressure sensor 7
p_aSmall additional pressure Δp_aSo that
Control is performed (S11). SV_a= P_a+ Δp_a(Δp_a> 0) SV_b= P_b+ Δp_b(Δp_b> 0) SV_c= 0 (1) Thus, during the general work in step S11, the boom
Throttle pressure S of the electromagnetic pressure reducing valve 3 and the arm pulling electromagnetic pressure reducing valve 5
V_b, SV_aValue is always pilot pressure p on the boom_b,
Pilot pressure p_aThan the additional pressure Δp_b,
Δp_aBy setting only a large value,
From the pilot valve 9 and the pilot valve 10
Pilot pressure on the boom of each spilled pilot oil
p_b, Arm pull pilot pressure p_aIs a solenoid valve on the boom
3 and the arm pulling electromagnetic pressure reducing valve 5
The pilot pressure transmitted to the control valve 1 is the pilot on the boom
Pressure p_b, Arm pull pilot pressure p_aSuppress to a smaller value
The movement of the boom 16 and the arm 17 is controlled by the boom operation.
Operator who operated the operating rod 9a and the operating rod 10a for the arm
Is not different from the intended movement
You.

Since the complementary pilot pressure p _c generated by the complementary pressure generating electromagnetic pressure reducing valve 4 is unnecessary in this case, the value of the throttle pressure SV _c is set to 0. In addition, the additional pressure Δ
p _b, are we small value Delta] p _a, when the general working control procedure S11 is moved to the initial migration automatic trajectory control described later completed, the boom on the solenoid pressure reducing valve 3 and the arm pulling solenoid pressure reducing valve 5 This is because the rise time of the control operation can be shortened as much as possible by shortening the moving distance of the spool so that the operation can be quickly shifted to the initial movement transition work automatic trajectory control operation.

FIG. 9 shows a control current e of the arm pulling electromagnetic pressure reducing valve 5.
FIG. 4 is a characteristic diagram showing _a relationship between _a and the throttle pressure SVa. As shown in the figure, the control current e _a so that the equation (1) is always satisfied.
By controlling the value of, the arm pull pilot pressure p _a can always be transmitted downstream of the arm pull electromagnetic pressure reducing valve 5. It is exactly the same also in the relationship between the throttle pressure SV _b control current e _b. Also, the additional pressure Δp
_b, since Delta] p _a is a small value, the control current e
_a small control current e _a 'to quickly move the spool of the arm pull solenoid pressure reducing valve 5 when it is a pressure diaphragm SV
can be transferred to _a '.

Next, in step S12, the bucket 18
It is determined whether the cutting edge C (x, y) of No. 1 is within the leveling work start position region R, that is, whether the leveling work start region condition [A1] is satisfied (C (x , Y) ∈R?). The control device 11 controls the bucket 18 based on the information about the rotation angles θ _b , θ _a , and θ _bu of the boom 16, the arm 17, and the bucket 18 detected by the rotation angle sensors 12 to 14 of the work machine.
The coordinates (x, y) of the cutting edge C are always calculated, and it is determined whether or not the coordinates (x, y) of the cutting edge C are within a predetermined leveling work start position area R read from the ROM. .

FIG. 13 is an explanatory view showing the standard work starting position area. In the figure, the hatched area is the leveling work start position area R. The work start position region R is set as a region where the frequency of the start of the smoothing operation is considerably high by checking the position of the blade edge C of the bucket 18 at the start of the smoothing operation by a large number of operators. It should be noted that, for reference, some of the initial positions of the buckets when the blade edges C of the buckets 18 are not within the leveling work start position region R are illustrated in this figure. As described above, the position of the blade edge C of the bucket 18 is calculated based on the relative angle of the joint portion of the rigid columnar body of the working machine detected by the rotation angle sensors 12 to 14, respectively.
The determination as to whether or not the position of the blade edge C of the bucket 18 obtained by the calculation is within the preset work start position region R is the determination content of the standard work start region condition.

[0038] If the determination result Yea, moves to Step S13, it is determined whether or not meeting the leveling work start operation range condition [A _L]. That is, (a), (b),
(C) to indicate the operation range condition [A _L alpha], [A _L beta],
It is determined whether [A _L γ] is satisfied. In particular,
Pilot pressure on boom p _b , arm pull pilot pressure p _a
Change versus time, i.e., these pilot pressure p _b, p _a time obtained by differentiating the boom on the pilot pressure change what v _b, when the arm pulling pilot pressure variation v _a, operating range condition [A _L alpha] is p _a1 ≤ p _a ≤ p _a2 , p _b1 ≤ p _b ≤ p _b2 and v _a3 ≤ v _a ≤ v _a4 , v _b3 ≤ v _b ≤ v _b4 where p _a1 , p _a2 << p _amax (arm-maximum pilot Pressure), p _b1 , p _b2 << p _bmax (maximum pilot pressure on boom), v _a3 , v _a4 ≈ v _amax (maximum pilot pressure fluctuation of arm pull) / 2, v _b3 , v _b4 ≈ v _bmax (maximum on boom) Pilot pressure fluctuation) / 2 (2 '). When satisfying the operation range condition [A _L alpha], when the value becomes 1, is not satisfied, the virtual function Ψα value becomes 0 (p
_a, p _b, v _a, by defining a v _b), the operation range condition [A _L alpha] can be easily expressed as Ψα = 1 ...... (2).

Similarly, the operating range condition [A _L β] is as follows: p _a3 ≤p _a ≤p _a4 , p _b1 ≤p _b ≤p _b2 and v _a1 ≤v _a ≤v _a2 , v _b3 ≤v _b ≤v _b4 where p _a3 , p _a4 ≒ p _amax / 2, v _a1 , v _a2 ≪v _amax (3 ′). A virtual function ψβ (p that has a value of 1 when the operating range condition [A _L α] is satisfied and has a value of 0 when the operating range condition [AL α] is not satisfied.
_a , p _b , v _a , v _b ), the operation range condition [A _L β] can be expressed as Ψβ = 1 (3).

[0040] Similarly, the operating range conditions [A _L gamma] _{is, p a1 ≦ p a ≦ p} a2, p b3 ≦ p b ≦ p b4 and _{v a3 ≦ v a ≦ v a4} , v b1 ≦ v b ≦ v _b2 However, the _{p b3, p b4 ≒ p bmax} / 2, v b1, v b2 «v bmax ...... (4 '). When satisfying the operation range condition [A _L gamma], when the value becomes 1, is not satisfied, the virtual function Ψγ value becomes 0 (p
_a, p _b, v _a, by defining a v _b), the operation range condition [A _L gamma] can be expressed as Ψγ = 1 ...... (4). Eventually, leveling work start operation range condition [A _L] is Ψα = 1, the Ψβ = 1 or Ψγ = 1 ...... (5).

Note that p _ai , p _bi , v _ai , v _bi (i = 1
As the value of ~ 4) the above, a number of operator statistical processing on average examined initial operation state of the working start of the operation rod by, leveling work start frequency large arm pulling pilot pressure p _a, boom Upper pilot pressure p _b , arm pull pilot pressure fluctuation v
_a, is set as a boundary value in the range of the pilot pressure change v _b boom. Therefore, as a result of performing statistical processing on the initial operation state at the start of the leveling operation, the operation range condition [A _L α],
[A _L beta], [A _L gamma] can may not be clearly distinguished from each other.

[0042] If the determination result of step S12 and steps S13, both Yea, i.e., leveling work start area condition [A _R]
If and leveling work starting operation range condition [A _L] is satisfied together, that is, if the cutting edge C of the bucket 18 is in the operation start position in the region R shown in FIG. 8, (5) it is satisfied For example, the procedure proceeds to step S14 in FIG. 6, and the main control of the leveling operation automatic trajectory control is started. In this procedure, the automatic trajectory control (I) for the initial transfer work is performed to correct the operation of the horizontal leveling transfer work manually performed by the operator to smoothly move the blade edge C of the bucket 18 to the horizontal reference plane S _0. The smooth leveling work automatic trajectory control (II) can be smoothly performed. As a result, when the automatic trajectory control for the rapid leveling operation is introduced, the automatic control of the horizontal leveling operation fails due to the operation delay of the hydraulic control system or the like, and the vertical vibration of the bucket 18 occurs due to the delay of the control signal feedback of the control system. Can be prevented.

FIG. 10 shows the control currents e _b and e output to the boom-mounted electromagnetic pressure reducing valve 3 and the arm pulling electromagnetic pressure reducing valve 5 in the automatic trajectory control (I) of the initial movement transition work of this embodiment.
signal waveform diagram for explaining the generation process of _a, FIG. 11 is an explanatory diagram of the initial trajectory of the cutting edge C of the bucket 18 shown in comparison with the conventional example due to initial migration automatic trajectory control (I), 1
2 control current e _b shown in FIG. 1, diaphragm pressure respectively generated on the solenoid pressure reducing valve 3 and the arm pulling solenoid pressure reducing valve 5 boom by e _a SV _b, boom applied to SV _a and hydraulic control valve 1 FIG. 4 is a pressure waveform diagram of an upper actual pilot pressure p _br and an arm pull actual pilot pressure p _ar . In this example, the state at the time of initial movement when an unskilled operator operates a hydraulic excavator to perform leveling work is shown in a slightly exaggerated manner. For convenience of explanation, here, the work start area condition leveling at time t = 0 [A _R] and operating range condition results that meet [A _L alpha], which has shifted to the initial migration automatic trajectory control (I) And

The boom on the pilot pressure p _b and the arm pulling pilot pressure p _a each p _b0, p _a0, the boom on the pilot pressure variation v _b and the arm pulling pilot pressure variation v _a respective v _b0, v _a0 at this time Then, since the expression (2) is established, p _a1 ≤ p _a0 ≤ p _a2 , p _b1 ≤ p _b0 ≤ p _b2 and v _a3 ≤ v _a0 ≤ v _a4 , v _b3 ≤ v _b0 ≤ v _b4 ... (2 '') Holds.

At the start of the operation, the operator operates the boom operation stick 9a.
Operation rod 1 for arm that is too strong for lifting operation
In the conventional example in which the initial movement shifting work automatic trajectory control (I) is not performed when the pulling operation of 0a is performed, as shown in FIG. As a result, the initial locus of the blade edge C of the bucket 18 undulates up and down. Therefore, in the present embodiment, the control device 11
Is a control current e _b , respectively, to the on-boom electromagnetic pressure reducing valve 3, the complementary pressure generating electromagnetic pressure reducing valve 4 and the arm pulling electromagnetic pressure reducing valve 5.
e _c, and outputs the e _a, hydraulic squeezing pressure of the pilot oil that flows out of the electromagnetic pressure reducing valves 3~5 SV _b, SV _c, SV
By controlling the pilot pressure so as not to exceed _a , as shown in FIG.
Is moved from the initial movement state to the horizontally moving state along the smooth horizontal reference plane S ₀ . The period during which the automatic trajectory control (I) for the initial transition work is performed is Δt _I.

In order to carry out the initial movement work automatic locus control (I), first, the initial value SV _a0 = p _a0 + Δp _a of the throttle pressure SV _a of the arm pulling electromagnetic pressure reducing valve 5 and the initial movement work automatic locus control (I ) at the end of the arm pulling pilot pressure p _a smoothly connecting two points of the target value p _ae of computing the function expression of the auxiliary curve <3>. In this embodiment, for simplicity, this function is approximated by a straight line.
An auxiliary curve capable of realizing a trajectory that can transition to the smoothest horizontal smoothing work automatic trajectory control (II) after t _I is experimentally obtained, and a better initial movement transition automatic trajectory can be obtained by using the function formula of the auxiliary curve. Control (I) becomes possible. Here, the function of the auxiliary curve <3> is represented by λ (p _a0 , p _ae , t). In the horizontal leveling operation automatic trajectory control (II), since there is a possibility that the maximum pulling operation of the arm operating rod 10a may be performed, even in such a case, it is possible to smoothly shift to the horizontal leveling operation automatic trajectory control (II). to control such, the value of the target value p _ae arm pulling pilot pressure p _a is set to the value of the maximum value near the arm pulling pilot pressure p _a.

[0047] Thus, the function _{λ (p a0, p ae,} t) Once you arithmetic function expression is, throttle pressure is generated with respect to the arm pull solenoid pressure reducing valve 5 when performing ordinary General Working Procedure S11 SV _a = p _a + Δp _a same stop pressure and SV _a value and the function _{λ (p a0, p ae,} t) to select the smaller value by comparing the values of initial migration automatic trajectory control this (I) Throttle pressure S generated for the arm pulling electromagnetic pressure reducing valve 5 in
Let V _aI . _{That, SV aI = min (p a} + Δp a, λ (p a0, p ae, t)) ...... (6) In the specific example shown in FIG. 10, the arm pull solenoid pressure reducing valve 5 is detected by the pressure sensor 7 curve <1> showing the arm pulling pilot pressure p _a is the output, and the curve <4> indicating the additional pressure Delta] p _a is applied thereto (p _a + _{Δp a),} the function λ
From the auxiliary curve <3> indicating ( _pa0 , _pae , t), FIG.
A curve <5> showing the throttle pressure SV _aI shown in FIG. Arm pulling actual pilot pressure p actually applied to hydraulic control valve 1
_ar is not the throttle pressure SV _aI shown by this curve <5>,
It becomes the value shown by the curve <6>. _{That, p ar = min (p a} , SV aI) ...... (7) Next, control of the boom on the pilot pressure applied to the hydraulic control valve 1 in the initial migration automatic trajectory control (I) will be described. As shown in FIG. 1, the on-boom actual pilot pressure p _br applied to the hydraulic control valve 1 is higher than the pressure of the pilot oil flowing out from the on-boom electromagnetic pressure reducing valve 3 and the complementary pressure generating electromagnetic pressure reducing valve 4. The pressure is generated by being selected by the high pressure selection valve 2. Throttle pressure SV at the boom on-board electromagnetic pressure reducing valve 3 in the initial trajectory transition work automatic trajectory control (I)
_bI is the initial value SV _b0 = p _b0 + Δp of the throttle pressure SV _b , similarly to the throttle pressure SV _aI for the arm pull solenoid pressure reducing valve 5.
_b and an auxiliary curve <8> that smoothly connects between two points of the target value p _be of the on-boom pilot pressure p _b at the end of the initial movement transfer automatic trajectory control (I). That is, auxiliary curve <8
Assuming that the function of> is κ, the function κ is a function of the initial value p _b0 of the on-boom pilot pressure p _b , the target value p _be, and the time t, and is approximated by a straight line in this embodiment. The target value p _be
Is set as the pilot pressure p _b on the boom after the period Δt _I when the relatively slow horizontal pulling trajectory control is performed, and is actually set as the minimum pilot pressure p _b on the boom after the period Δt _I obtained experimentally. It

Meanwhile, the diaphragm pressure to supplement pressure generating solenoid pressure reducing valve 4, i.e., complementary pilot pressure is correlated with the arm引実pilot pressure p _ar actually applied to the hydraulic control valve 1,
The pilot pressure p on the horizontal pulling boom for performing the normal horizontal pulling locus control for moving the cutting edge C of the bucket 18 horizontally
_{Let bL} . The pilot pressure p _bL on the horizontal boom can be obtained by the following procedure. In the present embodiment, only the combined operation of the boom 16 and the arm 17 is taken into consideration, and the leveling operation takes into consideration the case where the load is light. Therefore, the blade edge C (x,
Speed V (V _x of y), V _y) is the time generally work is determined arm pulling pilot oil flow rate Q _a of pilot oil flowing out from the arm pull solenoid pressure reducing valve 5, the boom on the pilot oil flow rate Q _b. Further, since the discharge flow rate Q _max of the hydraulic pump is known by the oil discharge flow rate detector 19, the arm pull pilot oil flow rate Q _a and the boom top pilot oil flow rate Q _b are the arm pull pilot pressure p _a and the boom top pilot pressure p a. _b
Is determined by

[0049] Thus, x the velocity V of the blade edge C of the bucket 18, y component, V _x, V _y is _{V x = f (x, y} , Q a, Q b) = F (x, y, p a, p _b , Q _max ) V _y = g (x, y, Q _a , Q _b ) = G (x, y, p _a , p _b , Q _max ) (8) Therefore, the function (curve <7>) representing the horizontal pulling trajectory control can be obtained by setting the vertical speed component V _y = 0 of the cutting edge C of the bucket 18 in the equation (8). G (x, y, p _a , p _b , Q _max ) = 0 By solving this equation for the pilot pressure p _b on the boom, a function H representing the horizontal pulling trajectory control of the curve <7> is obtained.
That is, p _bL = H (x, y, p _a , Q _max ) (9) can be obtained. This means that, in the horizontal pulling trajectory control of the blade edge C (x, y) of the bucket 18, the boom pilot pressure p _bL is naturally determined to be the arm pulling pilot pressure p _a as _a matter of course. Shows.
In practice, the function H by measuring the arm pulling pilot pressure p _a and the boom on the pilot pressure p _b at the time of performing horizontal pulling trajectory control experimentally in advance _{(x, y, p a,} Q max) is determined.
The data of the function H (x, y, p _a , Q _max ) is stored in the memory, and when performing the horizontal smoothing work automatic trajectory control (II), the control device 11 reads the function H from the memory. Data of the boom pilot pressure p _b corresponding to the arm pull pilot pressure p _a at the time of performing the horizontal pull trajectory control by operating the arm operating rod 10a at a desired work speed, Pilot pressure p on the boom
The control current e _b to give _b outputs on the solenoid pressure reducing valve 3 boom. In the above-mentioned initial trajectory transition work automatic trajectory control (I), the data of the function H is the complementary pressure that generates the horizontal pulling boom upper pilot pressure p _bL with respect to the arm pulling actual pilot pressure p _ar actually applied to the hydraulic control valve 1. product used to make a control current e _c of the solenoid pressure reducing valve 4.

Therefore, in the specific example shown in FIG. 10, the throttle pressure SV _bI for the boom- _mounted electromagnetic pressure reducing valve 3 is _equal to the function κ.
(P _b0 , p _be , t) is determined by (p _b0 , p _be , t), and the boom pilot pressure p _b ′ actually applied to the high pressure selection valve 2 from the boom solenoid pressure reducing valve 3 is the boom pilot pressure p _b (curve in FIG. 10). <2>) is a function κ (p _b0 , p _be ,
Curve <9> shown in FIG. 12 in which a large value is limited by t)
become that way. Then, the high pressure selection valve 2 selects the boom upper pilot pressure p _b ′ for a short time Δt ₀ immediately after the start of control, and thereafter selects the horizontal pull boom upper pilot pressure p _bL shown by the curve <7>. The actual pilot pressure p _br on the boom indicated by the curve <10> applied to the hydraulic control valve 1
Becomes That is, p _br = max (p _b ′, p _bL ) ... (10) Note that the above-mentioned short time Δt _0, as shown in FIG. It corresponds to the transition period. As described above, in the present embodiment, after starting the initial movement transition work automatic trajectory control (I), the short time Δt _0.
After the transition during the transition period, the operating state at the time of initial movement is gradually shifted to the horizontal pulling trajectory control. Smooth automatic control can be performed without causing

That is, in the specific example shown in FIG. 10, the arm pull pilot pressure p _a and the boom pilot pressure p _b are manually operated by the operator for a short period of time after starting the initial motion transition work automatic trajectory control (I). without change follow the arm引実pilot pressure p _ar and horizontal pulling the boom on the pilot pressure p _bL is output to, then the function _{λ (p a0, p ae,} t) and the function _{κ (p b0, p be,} t) Respectively, a large value is limited by SV _a = λ, (p _a + Δp _a ) and SV _b = p
_The control will be shifted to the actual horizontal trajectory control by _bL . In this process, since there is no discontinuity or sudden change in the arm pulling pilot pressure p _a and a boom on the pilot pressure p _b,
No impact occurs on the cylinder driving the boom 16 or the arm 17.

Next, returning to FIG. 6, the description of the operation of the leveling operation automatic trajectory control will be continued. In step S15, step S14
It is determined whether or not the condition for stopping the smoothing operation automatic trajectory control has been satisfied while continuing the initial movement automatic operation trajectory control (I) in. That is, if the stop condition of the smoothing work automatic trajectory control is represented by Φ _I , it is determined whether Φ _I = 1. The specific contents of the cancellation condition Φ _I, the boom operating rod 9
When the amount of raising operation of a is considerably large, when the raising and lowering speed is considerably large, or when the boom operating rod 9a is returned to the neutral position, or when the raising and lowering speed of the arm operating rod 10a is considerably large, or for the arm Operating rod 10a
Is returned to the neutral position.

In the operation of the leveling work, since the boom and arm operation rods 9a and 10a are rarely operated in this way, the operator stops the leveling work when the above operation is performed. Attempting to do so, or judging that there was no intention to perform the leveling work from the beginning, the initial movement work automatic locus control (I) or horizontal leveling work automatic locus control (II) was stopped, and the normal Move to automatic trajectory control (IV) for horizontal leveling work release for general work. When the operation contents of the boom and arm operation rods 9a and 10a for horizontal leveling work automatic trajectory control release are formulated, p _b ≧ p _b5 (p _b5 >>0); p _b = 0; v _b ≧ v _b5 (V _b5 >>0); v _b ≤v _b6 (v _b6 <<0); v _a ≥v _a5 (v _a5 >>0); v _a ≤v _a6 (v _a6 <<0); p _a = 0 ( 11)

If the result of the determination in step S15 is negative, that is,
When the stop condition Φ _I of the leveling work automatic trajectory control is 0, it is determined whether the time t has passed by Δt _I (S).
16). When the time t has elapsed by Δt _I, the required period of the initial movement transition automatic trajectory control (I) ends, so the process proceeds to step S17 in FIG. 7. If the time t has not yet elapsed by Δt _I , the procedure proceeds to step S17. Returning to S14, the initial movement work automatic trajectory control (I) is continued. In step S17, horizontal leveling work automatic trajectory control (II) is performed. In the horizontal trajectory control automatic trajectory control (II), the arm pulling electromagnetic pressure reducing valve 5
For the diaphragm pressure SV _a The _{SV a = p a + Δp a} , squeezing pressure of the boom on the solenoid pressure reducing valve 3 SV _b and aperture complementary pressure generating solenoid pressure reducing valve 4 pressure SV _c, initial migration in steps S14 In the automatic trajectory control (I), the function H
_{(X, y, p a,} Q max) and for the儘転horizontal pulling boom on the pilot pressure p _bL made with, the throttle pressure SV _b, SV _c of the electromagnetic pressure reducing valve 3,4. Thereby, it is possible to realize the horizontal leveling operation automatic trajectory control (II) in which the cutting edge C (x, y) of the bucket 18 is horizontally moved at the operation speed according to the amount of pulling operation of the arm operation rod 10a by the operator. .

In the next step S18, it is determined whether or not the condition for stopping the smoothing work automatic trajectory control is satisfied, as in the case of the initial movement work automatic trajectory control (I). That is, the cancellation condition of the leveling work automatic trajectory control is expressed as [Phi _II, [Phi _II
It is determined whether or not = 1. The specific contents of the stop condition Φ _II are as follows: when the operation amount of the boom operation rod 9a is considerably large, when the raising / lowering speed is considerably large, or when the boom operation rod 9a is returned to the neutral position or is very small,
Or, when the raising / lowering speed of the arm operating rod 10a is considerably high, or when the arm operating rod 10a is returned to the neutral position or is extremely small. Horizontal leveling work Boom and arm operation rods 9a, 1 for automatic trajectory control release
When formulating operation content _{0a, p b ≧ p b6 (} p b6 »0); 0 ≦ p b ≦ p b7 (p b7 ≒ 0); v b ≧ v b8 (v b8 »0); v b ≦ v _b10 (v _b10 <<0); v _a ≧ v _a7 (v _a7 >>0); v _a ≦ v _a8 (v _a8 <<0); 0 ≦ p _a ≦ p _a5 (p _a5 ≈0) ...... (11 ).

If the result of the determination in step S18 is true, that is, if the stop condition Φ _II = 1 for the leveling work automatic trajectory control,
The automatic trajectory control (II) for horizontal leveling work is stopped, and the automatic trajectory control for horizontal leveling work release (IV) for normal ordinary work is shifted to. If the result of the determination in step S18 is negative, it means that the correction condition M (v _b ) for correcting the horizontal movement locus drawn by the blade edge C of the bucket 18 is satisfied, that is, the horizontal pulling position correction control (III) is performed. Correction condition M (v _b ) =
It is determined whether it is 1 (S19). As described above, the correction of the horizontal movement trajectory drawn by the cutting edge C of the bucket 18 is performed because the horizontal tracing work automatic trajectory control (II) is actually performed, and the horizontal movement of the cutting edge C of the bucket 18 is drawn. This is because the movement locus may not match the reference plane S ₀ intended by the operator, or may be a plane deviated from the reference plane S ₀ due to an error in the device.

The specific operation contents of the correction condition M (v _b ) are when the operation speed of raising or lowering the boom operation rod 9a is large to some extent (medium). Boom and arm operation rods 9a, 10 for horizontal leveling and automatic trajectory control correction
When the operation content of a is formulated, v _b7 ≤ v _b <v _b8 (0 << v _b7 <v _b8 ); v _b10 <v _b ≤ v _b9 (v _b10 <v _b9 << 0) ... (12) Become. If the decision result in the step S19 is negative, a step S17
Then, the horizontal smoothing operation automatic trajectory control (II) is continued, and if the result of the determination in step S19 is true, that is, if the horizontal moving trajectory correction condition M (v _b ) = 1, the horizontal smoothing described below is performed. Perform position correction control (III).

[0058] That is, it is determined whether or not the pilot pressure variation v _b is positive boom (S20), the determination result if Yea, the boom on the pilot pressure p _b corresponding to the boom on the pilot pressure variation v _b increase amount Δp throttle pressure _bu was added to the horizontal pulling the boom on the pilot pressure p _bL boom on the solenoid pressure reducing valve 3 SV _b and the diaphragm pressure complementary pressure generating solenoid pressure reducing valve 4 S
And V _c (S21), if not the determination result in Step S19 is subtracted reduction Delta] p _bd boom on the pilot pressure p _b corresponding to the boom on the pilot pressure variation v _b from the horizontal pulling the boom on the pilot pressure p _bL the throttle pressure SV _b and diaphragm pressure SV _c complementary pressure generating solenoid pressure reducing valve 4 of the boom on the solenoid pressure reducing valve 3 Te (S22). Step S21 or step S22
Is completed, the process returns to step S17 to continue the horizontal leveling work automatic trajectory control (II). As is clear from the above description, if v _b9 <v _b <v _b7 , that is, if the raising or lowering operation speed of the boom operation rod 9a is smaller than medium, the horizontal leveling work automatic trajectory control ( II)
Is maintained.

FIG. 14 shows a state in which the operator operates the boom operating rod 9 while performing the horizontal tracing work automatic trajectory control (II).
After performing a raising operation at a speed greater than a medium speed and maintaining a predetermined operation amount, a pilot on the boom detected by the pressure sensor 6 when the operation of lowering the boom operation rod 9a at a speed higher than the medium speed is performed. Pressure p _b and control currents e _b and e _c
Pressure SV of boom-on electromagnetic pressure reducing valve 3 controlled by
6 is a waveform diagram showing the course of _b and the throttle pressure SV _c of the complementary pressure generating electromagnetic pressure reducing valve 4. FIG. As shown in the figure, the boom on the pilot pressure fluctuation v _b by pushing operation of the boom operating lever 9a of the operator was somewhat large, the diaphragm of the boom on the solenoid pressure reducing valve 3 pressure SV _b and complementary pressure generating solenoid pressure reducing valve 4 once the throttle pressure SV _c, the increase amount Delta] p _bu only after increasing the horizontal pulling boom on the pilot pressure p _bL, the relatively large retraction operation subsequent boom joystick 9a, reduction Delta] p _bd only horizontal pulling boom on the pilot Pressure p
Horizontal pulling position correction control (III) is performed so as to decrease from _bL .

Next, when the result of the determination in the step S15 or the step S18 is correct, the procedure shifts to the steps S23 to S23 in FIG.
The automatic trajectory control (I
Explain the contents of V). FIG. 17 shows that during the initial movement transition automatic trajectory control (I), the amount of operation of raising the boom operation rod 9a gradually increases, and the boom-on-boom pilot pressure p _b detected by the pressure sensor 6 becomes p _b5 or more. And as a result,
[Phi _I = 1, and the leveling work automatic boom on the pilot pressure in the specific example in the case of trajectory control to stop conditions are met p _b, the control current e _b, the boom on the solenoid pressure reducing valve 3 which is controlled by e _c waveform diagram showing changes in throttle pressure SV _b and aperture complementary pressure generating solenoid pressure reducing valve 4 pressure SV _c, 18
Is a boom on the actual pilot pressure p _br applied to the hydraulic control valve 1 at that time, the horizontal pulling leveling work release automatic trajectory control (IV)
FIG. 11 is a waveform diagram showing a change in the actual pilot pressure p _br ′ on the virtual boom in the case where is not performed.

Hereinafter, description will be made in accordance with this specific example. As shown in FIG. 17, it is assumed that the boom top pilot pressure p _b increases during the initial transition work automatic trajectory control (I), and p _b ≧ p _b5 at t = T ₀ . At this time, the operator is trying to stop the leveling work, or
Judging that there was no intention to perform leveling work from the beginning, the initial movement work automatic trajectory control (I) is stopped,
If the normal work control of step S11 is immediately returned at the time of t = T ₀ , for example, the boom actual pilot pressure p _brI given to the hydraulic control valve 1 shown in FIG. 18 is shown by the curve <15>. Since the actual pilot pressure on the boom becomes discontinuous at t = T ₀ , p _brIV ′, a large impact force is applied to the boom cylinder connected to the hydraulic control valve 1, and the operator is surprised and feels uneasy. , The device may be damaged. Therefore, in the automatic trajectory control (IV) for releasing the horizontal smoothing work, the bucket 18 is used in the automatic trajectory control (I) for the initial movement.
In order that the locus of the blade edge C of the blade may be along the horizontal plane as quickly as possible, the control device 11 limits or reverses the operation command by the operator's manual operation of the boom operating rod 9a and the arm operating rod 10a. Control current e to bias the
_{Outputting b} , e _c and e _a to the boom-on electromagnetic pressure reducing valve 3, the complementary pressure generating electromagnetic pressure reducing valve 4 and the arm pulling electromagnetic pressure reducing valve 5, respectively, is stopped. Performs control to smoothly shift to faithful control.

In the following description, the control of the raising operation of the boom 16 will be described. However, the control of the pulling operation of the arm 17 is performed in exactly the same manner as described later. During the period in which automatic trajectory control (IV) is performed, the automatic trajectory control that has been performed until then is released, and a smooth transition to control that faithfully follows the operation command by the operator's manual operation is performed. a transitional period Delta] t ₁ to consist of complementary pressure decay time Delta] t ₂ Metropolitan attenuate diaphragm pressure SV _c complementary pressure generating solenoid pressure reducing valve 4 to 0.

[0063] First, in the transitional period Delta] t _1, the control unit 11 at time t = boom on throttle pressure solenoid pressure reducing valve 3 at the time t = T ₀ was discontinued initial migration automatic trajectory control (I) in T ₀ Starting from the coordinate point of SV _bI = SV _bIV ⁰ ,
The sum of the boom on the pilot pressure _{p b} = SV cIV ¹ at time t = T ₁ after period Delta] t ₁ and the additional pressure Δp _b (p _b + Δ
p _b ) = A straight line <11> ending at the coordinate point of SV _bIV ¹ and a throttle point SV _cI = SV _cIV ⁰ of the supplementary pressure generating electromagnetic pressure reducing valve 4 at time t = T ₀ as a starting point. t = T ₁
A straight line <12> having the coordinate point of the on-boom pilot pressure p _b = SV _cIV ¹ as the end point is calculated. Then, linear <11> during the transient Delta] t _1, <12> at a pressure diaphragm represented pressure respectively SV _BIV and diaphragm pressure SV _CIV become such control current e _b, e _c a boom on electromagnetic pressure reducing valve 3 and Output to the complementary pressure generating electromagnetic pressure reducing valve 4. That is, SV _bIV = p _b + [t · (Δp _b + Δs ₁ ) / Δt ₁ ] −Δs ₁ = p _b + (t / Δt ₁ ) · Δp _b + [(t / Δt ₁ ) −1] · Δs ₁ (However, Δs ₁ = p _b ⁰ _{−SV bIV} ⁰ , p _b ⁰ is the pilot pressure p _b on the boom at t = T ₀ ) SV _cIV = p _b + t · Δs ₂ / Δt ₁ −Δs ₂ = p _b + [(T / Δt ₁ ) −1] · Δs ₂ (where Δs ₂ = p _b ⁰ _{−SV cIV} ⁰ ) (13) In the specific example shown in FIG. Immediately after the start of (IV), since SV _bIV ⁰ <SV _cIV ⁰ , the actual pilot pressure p _br on the boom applied to the hydraulic control valve 1 is governed by the throttle pressure SV _cIV of the supplementary pressure generating electromagnetic pressure reducing valve 4. When the values of SV _bIV and SV _cIV are reversed, the value is controlled by the throttle pressure SV _bIV of the boom- _mounted electromagnetic pressure reducing valve 3. Then, when the throttle pressure SV _bIV exceeds the boom pilot pressure p _b , the boom actual pilot pressure p
_br matches the boom pilot pressure p _b . Accordingly, the actual pilot pressure p _br on the boom is as shown by a curve <14> shown in FIG.

In the complementary pressure decay period Δt ₂ , the control device 11 _{starts from} the coordinate point of the throttle pressure SV _cIV ¹ at time t = T ₁ and starts at the throttle pressure SV at time t = T ₂ .
A straight line <13> with the coordinate point of _cIV = 0 as the end point is calculated, and the pressure represented by this straight line <13> becomes the throttle pressure SV _cIV ,
(P _b + Δp _b) respectively output aperture pressure SV _BIV become such control current e _b, the e _c on the solenoid pressure reducing valve 3 and complementary pressure generating solenoid pressure reducing valve 4 boom. That is, SV _cIV = p _b ¹ −p _b ¹ · (t−Δt ₁ ) / Δt ₂ (where p _b ¹ is the boom pilot pressure p _{b at} t = T ₁ ) (14) Pulling the arm 17 in the control operation, the operation expression for calculating equation for calculating the SV _aIV is to calculate the _SV bIV (13) equation, the on pilot pressure p _b the arm pulling pilot pressure p _a boom, an additional pressure Delta] p _b The pressure difference Δp _a
s ₁ and not outside in are replaced each to the differential pressure Δs _{3. That, SV aIV = p a + t} · (Δp a + Δs 3) / Δt 1 -Δs 3 = p a + (t / Δt 1) · Δp a + [(t / Δt ₁₎ -1] · Delta] s ₃ (provided that , Δs ₃ = p _a ⁰ _{−SV aIV} ⁰ , p _a ⁰ is arm pull pilot pressure p _{a at} t = T ₀ (15) Horizontal leveling work release automatic according to the flow chart shown in FIG. to describe the trajectory control (IV), the control device 11 the boom on the solenoid pressure reducing valve 3, respectively control current e _b complementary pressure generating solenoid pressure reducing valve 4 and the arm pulling solenoid pressure reducing valve 5, e _c, and outputs the e _a , Throttle pressures SV _b , SV _c , S of the electromagnetic pressure reducing valves 3 to 5
V _a is (13), controls the pilot pressure so that the computed value (15) (S23). Then, a time to determine whether it is t = T ₁ (S24). If the determination result is negative, the control for smoothly shifting to the control faithfully following the operation command by the manual operation by the operator in the transition period Δt ₁ in step S23 is continued. Then, step S2
If the result of the determination in step 4 is true, the control device 11 sets the throttle pressure SV of the boom-on electromagnetic pressure reducing valve 3 and the arm pulling electromagnetic pressure reducing valve 5
_b, SV _a is (1), a diaphragm pressure SV _c is (14) for controlling the pilot pressure so that the computed value by the formula (S2
5). Thereafter, it is determined whether or not the time has reached t = T ₂ (S26). If the determination result is negative, the supplementary pressure generating electromagnetic pressure reducing valve 4 during the supplementary pressure decay period Δt ₂ in step S25
The throttle pressure SV _c continuing the control for attenuating to zero. If the determination result of step S26 is true, the first step S26
Return to 11 general work control.

FIG. 17 is an explanatory view showing a state when the horizontal leveling work automatic locus control (II) is executed after the initial movement work automatic locus control (I), and FIG. 18 additionally shows the horizontal pulling position change control. It is explanatory drawing which shows a mode when (III) is performed. As shown in FIG. 17, the initial movement work automatic trajectory control
The operation delay such processes or in the hydraulic control circuit (I), by the deviation amount from the reference surface S ₀ locus of the cutting edge C [Delta] [epsilon] of the bucket 18 which may deviate downward. Even in this case, the trajectory of the cutting edge C of the bucket 18 is determined by the operator on the reference plane S _0.
Operating rod 9a for boom
Horizontal pull position change control by slightly raising the
(III) is performed, and as shown in FIG. 18, the trajectory of the blade edge C of the bucket 18 can be matched with the reference plane S ₀ intended by the operator.

In addition, actually, the initial trajectory transition work automatic trajectory control is performed.
When the trajectory drawn by the cutting edge C of the bucket 18 is different from the one intended by the operator when the horizontal averaging work automatic trajectory control (II) is executed via (I), the operation rod for the boom is also used. It is possible to make the trajectory drawn by the blade edge C of the bucket 18 intended by the operator by performing the horizontal pulling position change control (III) by slightly raising the 9a. FIG. 19 shows that when the trajectory drawn by the cutting edge C of the bucket 18 is different from the one intended by the operator, the trajectory drawn by the cutting edge C of the bucket 18 is operated by slightly raising the boom operating rod 9a. It is explanatory drawing which shows a mode that a person performs control which changes to what it intended. As shown in the drawing, in this example, the trajectory to be drawn by the cutting edge C of the bucket 18 originally intended is set as the reference plane S ₀ , but is changed to the reference plane S ₀ ′ by the horizontal pulling position correction control (III). further,
Since the reference plane S ₀ ′ also differs from the desired trajectory,
The reference surface is changed to S ₀ ″.

In the above embodiment, since the attitude of the bucket 18 may be controlled so that it is always kept constant, the attitude of the bucket 18 can be easily controlled according to the prior art, and therefore the description of the control operation of the bucket 18 is omitted. did. Further, the case where the present invention is applied to the automatic locus control for leveling work of the hydraulic excavator has been described, but it can be applied to the earth and sand carrying work of the hydraulic excavator in exactly the same manner. In this case, in addition to the automatic control of the boom 16 and the arm 17, the automatic control of the revolving superstructure forming a part of the hydraulic excavator body 15 is also required. FIG. 20 shows an example of a hydraulic control circuit in which the present invention is applied to earth and sand transfer work of a hydraulic shovel. In the figure, reference numeral 20 denotes a revolving-body pilot valve, 20a denotes a turning operation rod, and the reference numerals with ['] indicate the same as those without ['] in the above embodiment. ing. In this example, each operation rod (9a, 10a, 20a) is constituted by an electric operation rod, and each electromagnetic pressure reducing valve (3 ', 5', 21) directly reduces the pressure of the pilot oil flowing out of the pilot pump 8. Is supplied to the hydraulic control valve 1. The automatic control of the working machine and the revolving superstructure in this case is the same as that of the above-mentioned automatic trajectory automatic trajectory control, and the description thereof will be omitted.

[0068]

As described above, according to the present invention, the operation state of the operation rod operated by the operator is monitored, and the operation amount of the operation rod and the change amount of the operation amount of the operation rod are set in advance. When it is determined that the operation state is within the predetermined range, the operation state is determined to be an initial operation for drawing a predetermined standard movement trajectory, and automatic trajectory control for automatically drawing the standard movement trajectory is performed. When it is determined that the absolute value of the change amount of the operation amount is larger than a predetermined value after the start, the automatic trajectory correction that automatically corrects the initial standard movement trajectory according to the change amount of the operation amount. While performing the control, it is determined whether or not the operation amount of the operation rod and the amount of change in the operation amount exceed other predetermined ranges set in advance. Since the standard automatic control of the trajectory was controlled to end It is possible to smoothly shift to the automatic control of the desired work locus simply by performing the normal operation of the operation rod without the need to input special operation information or the operation of the operation rod more carefully than necessary. If it is not, it is possible to provide an automatic trajectory control device of a hydraulic construction machine with extremely excellent operability that can correct the work trajectory without a sense of discomfort by performing the same operation as the normal correction operation. it can.

[Brief description of the drawings]

FIG. 1 is a hydraulic control circuit diagram according to an embodiment of the present invention.

FIG. 2 is an operation conceptual diagram for explaining an outline of operation of automatic trajectory control.

FIG. 3 is an operation conceptual diagram following FIG. 2;

FIG. 4 is an explanatory diagram showing specific contents of a leveling operation start operation range condition;

FIG. 5 is a flowchart of leveling work automatic trajectory control according to the embodiment.

FIG. 6 is a flowchart of the leveling operation automatic trajectory control following FIG. 5;

FIG. 7 is a flowchart of the leveling operation automatic trajectory control continued from FIG. 6;

FIG. 8 is a flowchart of leveling work automatic trajectory control following FIG. 7;

FIG. 9 is a characteristic diagram showing the relationship between the control current e _a of the arm pulling electromagnetic pressure reducing valve and the throttle pressure SV _a .

FIG. 10 is a signal waveform diagram for explaining a process of generating a control current output to the boom on-board electromagnetic pressure reducing valve and the arm pulling electromagnetic pressure reducing valve in the initial motion transition work automatic trajectory control.

FIG. 11 is an explanatory diagram showing the initial motion locus of the blade edge C of the bucket by the automatic motion control of the initial motion transition work in comparison with the conventional example.

FIG. 12 is a pressure waveform diagram of an actual boom-on pilot pressure and an arm-pulled actual pilot pressure applied to an on-boom electromagnetic pressure reducing valve, an arm pulling electromagnetic pressure reducing valve, and a throttle pressure and a hydraulic control valve.

FIG. 13 is an explanatory diagram showing a leveling work start position area.

FIG. 14 is a pressure waveform diagram of the boom pilot pressure p _b and the throttle pressure SV _b when the horizontal pulling position correction control is performed.

FIG. 15 is a pilot pressure waveform chart for explaining the contents of the automatic trajectory control for releasing the horizontal smoothing operation.

FIG. 16 is a pressure waveform chart of the pilot pressure applied to the hydraulic control valve.

FIG. 17 is an explanatory diagram showing a state when the horizontal smoothing operation automatic trajectory control (II) in the embodiment is executed.

FIG. 18 is a horizontal pulling position change control (II
Explanatory diagram showing the situation when (I) is executed

FIG. 19 shows horizontal pulling position change control (II
Explanatory diagram showing how I) is repeatedly executed

FIG. 20 is a hydraulic control circuit diagram in which the present invention is applied to earth and sand transfer work of a hydraulic shovel.

FIG. 21 is an explanatory view showing a state in which a leveling operation is performed by a conventional example.

FIG. 22 is a schematic diagram showing an example of an operation when an unskilled operator performs a leveling operation.

FIG. 23 is an explanatory view showing a state in which a desired earth and sand carrying work can be executed.

FIG. 24 is an explanatory diagram showing a state in which execution of a desired earth and sand transport operation has failed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hydraulic control valve 2 High pressure selection valve 3 Boom upper electromagnetic pressure reducing valve 4 Complementary pressure generating electromagnetic pressure reducing valve 5 Arm pulling electromagnetic pressure reducing valve 6,7 Pressure sensor 8 Pilot pump 9a Operation rod for boom 10a Operation rod for arm 11 Control device 12 ~ 14 Rotation angle sensor 15 Hydraulic excavator body 16 Boom 17 Arm 18 Bucket

Claims (1)

[Claims] 1. An elongated rigid columnar body such as an arm or boom connected by an articulated bending portion and driven by a cylinder or the like, and rotatably connected to a tip end thereof and driven by a cylinder or the like. In an automatic trajectory control device of a hydraulic construction machine, a working machine formed of a work body such as a bucket is driven by a hydraulic drive mechanism to automatically control a movement trajectory of the work body to be a desired one. The operating state of the operated operating rod is monitored, and it is determined whether the operating amount of the operating rod and the amount of change in the operating amount of the operating rod are within a predetermined range set in advance, and the determination result If so, it is determined that the operation state is an initial operation for drawing a predetermined standard movement locus, and the hydraulic drive mechanism is controlled to automatically move the work body to the standard movement locus. Automatic trajectory control And thereafter, the amount of change in the operation amount of the operation stick is monitored, and when it is determined that the absolute value of the amount of change in the operation amount is larger than a predetermined value, the operator corrects the trajectory of the automatic trajectory control. It is determined that it was intended, and automatic trajectory correction control that automatically corrects the initial standard movement trajectory according to the amount of change in the operation amount is performed, and the operating state of the operated operating rod is monitored. Then, it is determined whether or not the operation amount of the operation rod and the amount of change in the operation amount exceed another preset predetermined range, and if the result of the determination is yes, the operator It was judged that the operation state of the operating rod was not intended to continue the original standard movement trajectory control operation, and control was performed to terminate the original standard movement trajectory automatic control. Automatic trajectory control device.