JPH09100548A - Hydraulic control device of construction machinery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to automatically shift a hydraulic control device of construction machinery to the locus control from general work by judging whether control information in the front is in accord with information in the memory section or not by an operation section, and outputting a control signal from an output section. SOLUTION: When an operator controls pilot vales 12 and 14, an operation section of a controller 25 decides that pressure signals outputted from pressure sensors 9 and 10 are equivalent to set point stored in a memory section. Then, a control signal is outputted to a proportional solenoid valve 4 from an output section of the controller 25. A boom lifting spool A is driven by pilot pressure of a pilot oil pressure source 13, and a boom cylinder 23a is driven by pressure oil from a main hydraulic pump to raise a boom 23. By the constitution, controllability excellent in the shift to the locus control can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is provided in a construction machine such as a hydraulic excavator having a front including a boom and an arm, and is capable of performing trajectory control such as "leveling work" for finishing the ground flat. Regarding the control device.

[0002]

2. Description of the Related Art A construction machine such as a hydraulic excavator is shown in FIG.
As shown in FIG. 10, a boom 23 rotatably attached to the main body 18 forming a revolving structure, an arm 22 rotatably attached to the boom 23, and a bucket rotatably attached to the arm 22. It includes a front including 21 and a hydraulic cylinder for driving the front, that is, a boom cylinder 23a for rotating the boom 23, an arm cylinder 22a for rotating the arm 22, and a bucket cylinder 21a for rotating the bucket 21. . Although not explicitly shown in FIGS. 9 and 10, this hydraulic excavator includes a front detection device that detects a front posture, for example, a front angle sensor that detects a front rotation angle, and a boom cylinder 23.
a, arm cylinder 22a, and bucket cylinder 21
These cylinders 2 are provided corresponding to each of a.
3a, 22a, 21a are provided corresponding to the flow rate control means for controlling the flow rate, for example, a control valve having a spool for controlling the flow rate, the boom cylinder 23a, the arm cylinder 22a, and the bucket cylinder 21a. , These cylinders 23a, 22
a, 21a, an operating device for commanding the flow rate, for example, pilot valves, an operating amount detecting device for detecting the operating amounts of these pilot valves, and the operating amount detecting device and the above-mentioned front angle sensor. A controller for calculating a signal and outputting a control signal corresponding to the calculated value as a signal for driving the above-mentioned control valve.

An example of such a hydraulic excavator is shown in FIG.
As indicated by the arrow 53, the arm cylinder 22a is gradually extended while raising the boom 23, and the arm 22 is rotated in the direction approaching the main body 18 as indicated by the arrow 54 (arm cloud). The "leveling work" in which the bucket 21 is moved as indicated by the arrow 55 up to and the ground of the bucket 21 is flattened may be performed.

Further, as shown by an arrow 56 in FIG. 10, in order to release the earth and sand excavated by the bucket 21 to a predetermined position, the bucket 21 is kept in a constant posture while the bucket 21 is directed toward the main body 18 direction. "Sand transport work" may be carried out.

By the way, in the "leveling work" shown in FIG. 9 and the "earth and sand carrying work" shown in FIG. 10, it is necessary to accurately change the posture of the front. It is necessary to distribute an appropriate flow rate to each cylinder 23a, 22a, 21a while simultaneously operating two or three operating levers to be operated. This is a technique that requires considerable skill, and if the operation fails or the operator's skill is unskilled, the ground should be flattened by "leveling work" as shown in FIG. However, as shown in FIG. 12, the unevenness 57 is formed, and as shown in FIG.
Bucket 2 where you want to carry 9 without dropping it
1 will tilt and will drop the earth and sand 59.

[0006] In order to eliminate such difficulty of operation by an operator, techniques for realizing automatic excavation (trajectory control) have been conventionally proposed as listed below.

(1) JP-B-3-28544 (2) JP-B-3-13378 (3) JP-B-58-36135 (4) JP-A-3-25126 (5) JP-A-55 -30038 (6) JP-A-62-86235 (7) JP-A-1-318621 (8) JP-A-4-350220 (9) JP-A-62-72826 (10) Special JP-A-55-52437 (11) JP-A-4-348534 (12) JP-A-5-306458 (13) JP-A-6-092367 (14) JP-A-6-119874

[0008]

However, in each of the above-mentioned conventional techniques of "(1)" to "(14)", the setting of automatic excavation is complicated, and there is a problem in usability. For example, when determining the horizontal plane or the excavation area, it is necessary to press the button and store it in the control device. Alternatively, the operator had to operate the buttons on the panel near the operator and input the numerical values. In any case, the operator has to perform a special operation for performing the trajectory control, which is troublesome for the operator.

The above-mentioned "(1)""(3)"-
In the conventional technique of "(10)", an operator performs an excavation work by giving a command for automatic excavation (trajectory control) by using any one of the levers that originally needs to be operated when performing the work. There is. For this reason, in a series of operations such as heavy excavation operation, dumping operation, and suspended load operation, it becomes a special operation that is uncomfortable only when the automatic excavation operation is performed, and the desired work is realized. Therefore, there is a problem that the smoothness of the operation flow, that is, the continuity of the operation is impaired, and good operability cannot be obtained.

The present invention has been made in view of the above-mentioned circumstances in the prior art, and its object is to carry out a normal operation of driving the front of an operator without requiring any special button operation. An object of the present invention is to provide a hydraulic control device for a construction machine capable of naturally shifting from ordinary general work to trajectory control.

[0011]

To achieve this object, the invention according to claim 1 of the present invention comprises a construction machine having a front including a boom and an arm and a hydraulic cylinder for driving the front. And a front detecting device for detecting the posture of the front, a flow rate control means for controlling a flow rate supplied to the hydraulic cylinder, an operating device for instructing a flow rate supplied to the hydraulic cylinder, and an operation of the operating device. An operation amount detecting device for detecting an amount and a controller for calculating a signal output from the operation amount detecting device or the front detecting device and outputting a control signal corresponding to the calculated value to the flow rate control means are provided. In a hydraulic drive system for a construction machine, the controller outputs operation information based on the operation of the front, which is usually performed at the start of trajectory control, Therefore, a storage unit that stores the trajectory control start operation information, a calculation unit that determines whether or not the actual movable operation information based on the operation amount signal detected by the operation amount detection device matches the trajectory control start operation information, and When the arithmetic unit determines that the actual movable operation information matches the trajectory control start operation information, the output unit outputs a control signal for performing the trajectory control to the flow rate control means.

[0012] According to a second aspect of the present invention, in the above-mentioned first aspect of the invention, the controller previously stores, in advance, operation information based on the front operation that is normally performed when the trajectory control is stopped. A storage unit that stores the trajectory control stop operation information, a calculation unit that determines whether or not the actual movable operation information based on the operation amount signal detected by the operation amount detection device matches the trajectory control stop operation information,
A configuration including an output unit that outputs a control signal during normal operation associated with the suspension of the trajectory control to the flow rate control unit when the arithmetic unit determines that the actual movable operation information matches the trajectory control suspension operation information. I am doing it.

[0013]

In the invention according to claim 1 of the present invention, when the operator operates the operating device so that the front posture becomes the starting form of the trajectory control in consideration of performing the trajectory control, the operating device in this state is set. The operation amount of is detected by the operation amount detection device. Therefore, in the calculation unit of the controller, it is determined that the actual movable operation information based on the operation amount signal of the operation amount detection device and the trajectory control start operation information stored in the storage unit match. As a result, a control signal for performing the trajectory control is output from the output section of the controller to the flow rate control means.

The flow rate control means supplies a flow rate corresponding to the trajectory control to the hydraulic cylinder. In response to this, the front performs an operation corresponding to the trajectory control. In this way, the operator can operate the operating device in the same way as during normal work so that the front posture becomes the starting form of the trajectory control, and without any special button operation or the like, it will naturally occur. It is possible to shift to trajectory control.

In the invention according to claim 2 of the present invention,
In addition to the above-described operation, when the operator operates the operating device so that the front posture suspends the trajectory control in consideration of the termination of the trajectory control, the operation amount of the operating device in this state is detected as the operation amount. Detected by the device. Therefore,
In the calculation unit of the controller, it is determined that the actual movable operation information based on the operation amount signal of the operation amount detection device and the trajectory control stop operation information stored in the storage unit match.
As a result, the trajectory control is stopped, and the control signal for normal operation is output from the output section of this controller to the flow rate control means.

The flow rate control means supplies the flow rate corresponding to the operation amount of the operating device to the hydraulic cylinder in the same manner as during normal work. In this way, the operator operates the operating device in the same way as during normal work so that the posture of the front is such that the trajectory control is stopped, and no special button operation or the like is required. The trajectory control can be stopped.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a hydraulic control device for a construction machine according to the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of a first embodiment corresponding to claims 1 and 2 of the present invention, and FIG. 2 is a flowchart showing a processing procedure in a controller provided in the first embodiment shown in FIG. The first embodiment realizes the trajectory control of the "leveling work" shown in FIG. 9 described above.

The construction machine shown in FIG. 1 is a hydraulic excavator, and as described above, the hydraulic excavator is a boom 23 rotatably mounted on the main body 18 forming a revolving structure, and rotatably mounted on the boom 23. Arm 22, a front including a bucket 21 rotatably mounted on the arm 22, a hydraulic cylinder for driving the front, that is, a boom cylinder 23a for rotating the boom 23,
An arm cylinder 22a for rotating the arm 22 and a bucket cylinder 21a for rotating the bucket 21 are provided.

The first embodiment is provided with a front detection device for detecting the front posture, for example, a front angle sensor for detecting the front rotation angle and outputting it to the controller 25. The front angle sensor detects a relative angle of the boom 23 with respect to the main body 18 and outputs a angle signal to the boom angle sensor 24, and the arm 2 to the boom 23.
The arm angle sensor 19 that detects the relative angle of 2 and outputs an angle signal, and the bucket angle sensor 20 that detects the relative angle of the bucket 21 with respect to the arm 22 and outputs the angle signal.
It is constituted by and.

Further, a control valve 1 for controlling the flow rate supplied to the hydraulic cylinder for driving the front is provided. The control valve 1 includes, for example, a boom raising spool A and an arm cloud spool B. Further, it is provided with an operating device for instructing boom raising, for example, a pilot valve 12, and an operating device for instructing arm crowding, for example, a pilot valve 14. Further, a manipulated variable detecting device for detecting a manipulated variable of the pilot valve 12 for instructing boom raising, that is, a pressure sensor for detecting a pilot pressure that changes corresponding to the manipulated variable of the pilot valve 12 and outputting a pressure signal to the controller 25. 9 and a pressure sensor 10 that detects a pilot pressure that changes corresponding to the operation amount of the pilot valve 14 that commands the arm cloud and outputs a pressure signal to the controller 25.

Further, the shuttle valve 2 for selectively supplying the pilot pressure for driving the boom raising spool A and the pilot conduit connecting the shuttle valve 2 and the pilot valve 12 are provided and output from the controller 25. Is provided in the proportional solenoid valve 4 that is driven according to the control signal, the pilot hydraulic pressure source 13, and the pilot conduit that connects the pilot hydraulic pressure source 13 and the shuttle valve 2 described above.
The proportional solenoid valve 5 which drives according to the control signal output from the controller 25 is provided.

A control valve 1 having the boom raising spool A and the arm cloud spool B described above.
The shuttle valve 2, the proportional solenoid valves 4, 5, and the pilot hydraulic pressure source 13 are the flow rate supplied to the hydraulic cylinder that drives the front, that is, the boom cylinder 2 in this case.
3a and the arm cylinder 22a constitute flow rate control means for controlling the flow rate.

The controller 25 described above is composed of, for example, a microcomputer, and includes pressure sensors 9 and 10.
Of the boom angle sensor 24, the arm angle sensor 19, and the bucket angle sensor 20 and the front operation information that is normally executed at the start of the trajectory control, that is, the condition α to be described later. A storage unit that stores the control operation information as control start operation information, and the front operation information that is normally executed when the trajectory control is stopped, that is, a condition β described below, as the trajectory control stop operation information, and the operation amount detection device, that is, the pressure sensor 9. , 10 determines whether or not the actual movable operation information described later based on the pressure signals output from the pressure sensors 9 and 10 matches the above-described condition α, and the actual movable operation information based on the pressure signals output from the pressure sensors 9 and 10 determines the above trajectory. The control unit for determining whether or not it matches the control stop operation information and the control signal for performing the trajectory control, or the trajectory control Proportional solenoid valves 4 and 5 constituting the flow control means described above the control signals of normal operation with the stop
And an output unit for outputting to.

The condition α stored in the storage unit of the controller 25 described above includes the following condition 1 and condition 2. Condition 1 is the pilot valve 12 that performs the boom raising.
To the set value corresponding to the value of the pressure signal of the pressure sensor 9 detected according to the operation amount of the pressure sensor 10 and the value of the pressure signal of the pressure sensor 10 detected according to the operation amount of the pilot valve 14 that implements the arm cloud. Regarding the corresponding set value, the set value BV1 corresponds to the value of the pressure signal of the pressure sensor 9 corresponding to the operation amount of the pilot valve 12 at the start of the trajectory control, which is empirically obtained in the normal front drive.
In addition, as a set value AV1, a value corresponding to the value of the pressure signal of the pressure sensor 10 corresponding to the operation amount of the pilot valve 14 at the time of starting the trajectory control, which is empirically obtained during normal front driving, is set in the storage unit. It is stored in advance.

Condition 2 is a set value corresponding to the amount of change per unit time of the pressure signal of the pressure sensor 9 detected according to the operating speed of the pilot valve 12 for raising the boom, and the pilot for executing the arm crowd. The present invention relates to a set value corresponding to the amount of change per unit time of the pressure signal of the pressure sensor 10 detected according to the operating speed of the valve 14, and is a pilot at the start of trajectory control that is empirically obtained during normal front driving. The set value BS2 corresponds to the amount of change in the pressure signal of the pressure sensor 9 per unit time corresponding to the operating speed of the valve 12, and the pilot valve at the start of trajectory control that is empirically obtained during normal front drive. The set value AS corresponding to the change amount of the pressure signal of the pressure sensor 10 corresponding to the operation speed of 14 per unit time
2 is stored in the storage unit in advance.

In the case of the "leveling work" for finishing the ground flat, the operator usually operates at the position U shown in FIG.
As shown in FIG. 1, the toe of the bucket 21 is positioned at a place where finishing is desired, and the bucket 21 is slowly moved almost at the same time to start the “leveling work”. Therefore, the operation form of the front at the start of this "leveling work" can be considered to be an empirically almost unique operation form, and the above-mentioned set values BV1, AV1, BS2, AS2 are set.
Is effective as locus control start operation information stored in advance.

The condition β stored in the storage unit of the controller 25 described above includes the following condition I, condition II and condition III. Condition I is the pressure sensor 9 detected when the pilot valve 12 for raising the boom is in neutral.
And the set value corresponding to the value of the pressure signal of the pressure sensor 10 detected when the pilot valve 14 that implements the arm crowd is in the neutral position. The value corresponding to the value of the pressure signal of the pressure sensor 9 when the operation amount is 0 at neutral is set as the set value BV01, and the pressure signal of the pressure sensor 10 when the pilot valve 14 is neutral and the operation amount becomes 0. A value corresponding to the value of is set in advance in the storage unit as a set value AV01.

Condition II relates to a set value corresponding to the value of the pressure signal of the pressure sensor 9 detected according to the operation amount of the pilot valve 12 for raising the boom. Possible pilot valve 1
The set value B corresponding to the value of the pressure signal of the pressure sensor 9 corresponding to a relatively large operation amount exceeding the operation amount of 2 is set value B.
It is stored as a VL in the storage unit in advance.

The condition III is that the pressure sensor 9 is detected according to the operating speed of the pilot valve 12 for raising the boom.
Setting value corresponding to the change amount of the pressure signal of per unit time,
And a set value corresponding to the amount of change per unit time of the pressure signal of the pressure sensor 10 detected according to the operating speed of the pilot valve 14 that implements the arm crowd. The set value BSL corresponds to the amount of change in the pressure signal of the pressure sensor 9 per unit time, which corresponds to an operating speed sufficiently higher than the operating speed of the pilot valve 12, and is empirically used in normal trajectory control. The pressure sensor 1 corresponding to a speed sufficiently higher than the operating speed of the pilot valve 14 that is considered to be
A value corresponding to the amount of change in the pressure signal of 0 per unit time is stored in advance in the storage unit as the set value ASL.

Here, in the case of trajectory control in the "leveling work" for finishing the ground flat, generally, when the operator does not perform trajectory control, the operator sets the pilot valve 12 for raising the boom to the neutral position or the pilot for performing arm crowding. The valve 14 is made neutral. Or, in order to hold the front at a high position,
The boom 23 is raised significantly (note that
The arm 22 may move greatly even during trajectory control). Alternatively, the operator empirically moves the boom 23 or the arm 22 at a high operating speed when not aware of the trajectory control. Therefore, the operation form of the front when the trajectory control in the "leveling work" is not performed can be empirically determined as described above, and the set values BV01, AV01, BV described above are set.
L, BSL, and ASL are effective as trajectory control stop operation information stored in advance.

Next, the operation of the first embodiment configured as described above will be described according to the processing procedure of the flowchart shown in FIG.

The controller 25 is operated in conjunction with the start of an engine (not shown) or in response to a command signal from a switch or the like from the outside. The angle signal of the angle sensor 20 is input to the controller 25, and control is started.

Now, as shown in step S1, the operator operates the pilot valves 12 and 14 to operate the boom cylinder 23.
It is assumed that normal general work, for example, earth and sand excavation work is performed by appropriately driving the arm cylinder 22a.

In step S2, the controller 25 determines whether or not the operation lever patterns of the pilot valves 12 and 14 satisfy a predetermined condition α (condition for starting the leveling work / trajectory control). That is, in the calculation unit of the controller 25, the pressure signal output from the pressure sensor 9 is equal to the set value BV1 at the start of the trajectory control of the condition 1 described above stored in the storage unit, and at the same time, output from the pressure sensor 10. It is determined whether the pressure signal to be generated is equal to the set value AV1 at the start of the trajectory control of the condition 1 described above stored in the storage unit. Further, in the calculation unit of the controller 25, the change amount of the operation speed of the operation lever of the pilot valve 12, that is, the change amount of the pressure signal of the pressure sensor 9 per unit time is stored in the storage unit. Is equal to the set value BS2 at the start of the locus control, and at the same time, the change amount of the operation speed of the operation lever of the pilot valve 14, that is, the change amount of the pressure signal of the pressure sensor 10 per unit time is
It is determined whether or not it is equal to the set value AS2 at the start of the trajectory control of the condition 2 described above stored in the storage unit.

In this case, since ordinary general work is performed, the above condition α, that is, condition 1 and condition 2 are not satisfied, and the trajectory control in step S3 is not executed, and the procedure S is executed.
Return to 1. At this time, the controller 25 outputs a control signal for normal operation to the proportional solenoid valves 4 and 5. Thereby, for example, the proportional solenoid valve 4 is controlled to form an open state that does not affect the supply of pilot pressure from the pilot valve 12 to the shuttle valve 2, and the proportional solenoid valve 5 is controlled from the pilot hydraulic power source 13 to the shuttle. It is controlled so as to form a closed state that restricts the supply of pilot pressure to the valve 2.

As a result, a pilot pressure corresponding to the operation amount of the pilot valve 12 is given to the pilot chamber of the boom raising spool A of the control valve 1 via the proportional solenoid valve 4 and the shuttle valve 2, and this boom raising spool is provided. A
Is driven, and the boom cylinder 23a is operated by the pressure oil discharged from the main hydraulic pump (not shown), and the boom 23 is driven accordingly. Further, a pilot pressure according to the operation amount of the pilot valve 14 is given to the pilot chamber of the arm cloud spool B of the control valve 1, the arm cloud spool B is driven, and the pressure discharged from the main hydraulic pump (not shown) is supplied. Arm cylinder 22 with oil
a operates, and the arm 22 drives accordingly. That is, it is possible to carry out normal general work such as excavation work in accordance with the operation of the pilot valves 12 and 14 by the operator.

Unlike such general work, the operator operates the pilot valves 12 and 14 in consideration of the locus control for performing the "leveling work", and, for example, the front is moved to the position U1 shown in FIG. 9 described above. Is positioned and the front is slightly driven as shown by the arrow 55 in FIG. 9, the determination at step S2 described above is satisfied. That is, in the calculation unit of the controller 25, the pressure signal output from the pressure sensor 9 is equal to the set value BV1 at the start of trajectory control stored in the storage unit, and at the same time, the pressure sensor 1
It is determined that the pressure signal output from 0 is equal to the set value AV1 at the start of trajectory control stored in the storage unit.
Further, the change amount of the pressure signal of the pressure sensor 9 per unit time is equal to the set value BS2 at the start of the trajectory control stored in the storage unit, and at the same time, the change amount of the pressure signal of the pressure sensor 10 per unit time. Is equal to the set value AS2 at the time of starting the trajectory control stored in the storage unit.

As a result, the procedure moves to step S3 and the trajectory control is executed. At this time, a control signal for closing the pilot conduit between the pilot valve 12 and the shuttle valve 2, for example, is output from the output part of the controller 25 to the proportional solenoid valve 4, and the proportional electromagnetic valve is output from the output part. On valve 5,
A control signal for appropriately opening the pilot conduit between the pilot hydraulic pressure source 13 and the shuttle valve 2 is output. That is, the operator operates the pilot valve 14 in consideration of the “leveling work” to supply the pressure oil to the pilot chamber of the arm cloud spool B, and the arm cylinder 22a.
Of the boom angle sensor 24, the arm angle sensor 19, and the bucket angle sensor 20 during the operation of extending the arm 22 to cloud the arm 22 as shown by the arrow 54 in FIG.
The angle signal is output from each of the
Is input to The calculation unit of the controller 25 calculates the rotation angle of the boom 23 for trajectory control corresponding to the movement of the arm 22 based on the angle signals output from these sensors 24, 19, 20 and calculates the calculated value. The control signal corresponding to is output to the proportional solenoid valve 5. Along with this, the pilot pressure of the pilot hydraulic pressure source 13 is given to the pilot chamber of the boom raising spool A via the proportional solenoid valve 5 and the shuttle valve 2, and this boom raising spool A is irrespective of the operation of the pilot valve 12. The boom cylinder 2 is automatically driven and is driven by pressure oil discharged from a main hydraulic pump (not shown).
3a is driven in the extending direction, whereby the boom 23 rises following the movement of the arm 22, and the desired "leveling work", that is, the blade edge of the bucket 21 is moved in the direction of arrow 55 in FIG. You can perform "leveling work" that finishes flat. In this way, the pilot valve 1
Along with the operations 2 and 14, it is possible to naturally shift from the normal general work to the trajectory control.

Further, after the "execution of trajectory control" in step S3 of FIG. 2 described above, as shown in step S4, the operating lever pattern of the pilot valves 12 and 14 has a predetermined condition β (leveling). The controller 25 determines whether or not work / trajectory control suspension conditions are satisfied. That is, in the calculation unit of the controller 25, whether the pressure signal output from the pressure sensor 9 is equal to the neutral setting value BV01 stored in the storage unit described above, or whether the pressure signal is output from the pressure sensor 10. It is determined whether the pressure signal is equal to the neutral setting value AV01 stored in the storage unit. Alternatively, it is determined whether or not the pressure signal of the pressure sensor 9 related to the boom raising is equal to or more than the set value BVL stored in the storage unit and corresponding to the relatively large operation amount of the condition II described above. Alternatively, the change amount per unit time of the pressure signal of the pressure sensor 9 related to the boom raising is set value BS corresponding to the high operation speed of the pilot valve 12 of the above-mentioned condition III stored in the storage unit.
Whether or not it is L or more, or the amount of change in the pressure signal of the pressure sensor 10 related to the arm cloud per unit time is stored in the storage unit.
It is determined whether or not the set value is equal to or higher than the set value ASL corresponding to the fast operation speed.

If it is assumed that the "leveling work" trajectory control is being performed, the determination at step S4 is not satisfied, the procedure returns to step S3, and the trajectory control described above is continued.

When the determination in step S4 is satisfied, the situation is such that the trajectory control is stopped, and the procedure returns to step S1 to shift to the normal general work described above. That is, as described above, at this time, the controller 25 outputs the control signal at the time of the normal operation to the proportional solenoid valves 4 and 5. For example, the proportional solenoid valve 4 supplies the pilot pressure from the pilot valve 12 to the shuttle valve 2. The proportional solenoid valve 5 is controlled so as to form an open state having no influence,
It is controlled to form a closed state that restricts the supply of pilot pressure from the pilot hydraulic pressure source 13 to the shuttle valve 2.

As a result, a pilot pressure corresponding to the operation amount of the pilot valve 12 is applied to the pilot chamber of the boom raising spool A of the control valve 1, the boom raising spool A is driven, and a main hydraulic pump (not shown) is operated. The boom cylinder 23a is operated by the discharged pressure oil, and the boom 23 is driven accordingly. Further, a pilot pressure according to the operation amount of the pilot valve 14 is given to the pilot chamber of the arm cloud spool B of the control valve 1, the arm cloud spool B is driven, and the pressure discharged from the main hydraulic pump (not shown) is supplied. The arm cylinder 22a is activated by the oil, and the arm 22 is driven accordingly. In this way, the trajectory control of the "leveling work" can be naturally shifted to the normal general work such as excavation work in accordance with the operation of the pilot valves 12 and 14 by the operator.

In the first embodiment constructed as described above, a special button is added in addition to the driving operation of the boom 23 and the arm 22 by the operator's pilot valves 12 and 14 which are usually carried out, that is, the front driving operation. Naturally "genuine" work from normal general work without requiring operations
It is possible to shift to the locus control of No. 3, and it is possible to ensure excellent operability when shifting to the locus control of this “leveling work” without giving the operator any trouble or uncomfortable feeling in operation. On the contrary, it is possible to shift from "trajectory control" trajectory control to normal general work naturally without giving the operator any trouble or discomfort in operation. Excellent operability can be ensured even when shifting to work.

FIG. 3 is a diagram showing a configuration of a second embodiment corresponding to claims 1 and 2 of the present invention. In the second embodiment, the “sand and sand carrying work” shown in FIG. 10 described above, that is, the “sand and sand carrying work” in which the bucket 21 is moved in the direction of the main body 18 while keeping the posture of the bucket 21 constant.
The locus control of is realized.

In the second embodiment, the control valve 1 for controlling the flow rate supplied to the hydraulic cylinder for driving the front side includes the boom raising spool A, the arm cloud spool B, and the bucket dump spool C. I have it. Further, an operating device for commanding a bucket dump, for example, the pilot valve 16 and the pilot valve 1
6 and a pressure sensor 11 that detects a pilot pressure that changes corresponding to the operation amount of the pilot valve 16 and outputs a pressure signal to the controller 25. , A shuttle valve 3 for selectively supplying a pilot pressure for driving the bucket dump spool C, and a pilot line connecting the shuttle valve 3 and the pilot valve 16 described above, and the control output from the controller 25 A proportional solenoid valve 8 that is driven according to a signal, a pilot hydraulic pressure source 15, and a pilot conduit that connects the pilot hydraulic pressure source 15 and the shuttle valve 3 described above are provided, and according to a control signal output from a controller 25. And a proportional solenoid valve 7 for driving.

In the second embodiment, a control valve 1 having a boom raising spool A, an arm cloud spool B, and a bucket dump spool C, shuttle valves 2 and 3, and proportional solenoid valves 4, 5 and 5. 7 and 8 and the pilot hydraulic power sources 13 and 15 supply the flow rate to the hydraulic cylinder that drives the front, that is, in this case, the boom cylinder 23a, the arm cylinder 22a, and the bucket cylinder 21a. A flow rate control means for controlling the is configured.

The controller 25 also includes pressure signals from the pressure sensors 9, 10, 11 and the boom angle sensor 24,
An input unit for inputting angle signals of the arm angle sensor 19 and the bucket angle sensor 20, and front operation information that is normally executed at the time of starting the trajectory control, that is, condition α1 described later, is stored in advance as trajectory control start operation information, and trajectory control is performed. When the operation is stopped, the front operation information that is normally executed, that is, the condition β1 described later, is stored in advance as the trajectory control stop operation information, and the operation amount detection device, that is, the pressure signal output from the pressure sensor 9, 10, 11. Based on this, it is determined whether the later-described actual movable operation information matches the above-described condition α1, and the actual movable operation information based on the pressure signals output from the pressure sensors 9, 10, 11 matches the above-described trajectory control stop operation information. The calculation unit that determines whether or not to perform it, the control signal that implements the trajectory control, or the normal operation that accompanies the termination of the trajectory control. A control signal proportional solenoid valve 4 when,
And an output unit for outputting to 5, 7, and 8.

The conditions α1 stored in the storage unit of the controller 25 described above include the following conditions 1a and 2a. The condition 1a depends on the set value corresponding to the value of the pressure signal of the pressure sensor 9 detected according to the operation amount of the pilot valve 12 for performing the boom raising, and the operation amount of the pilot valve 14 for performing the arm crowding. Related to a set value corresponding to the value of the pressure signal of the pressure sensor 10 detected and a set value corresponding to the value of the pressure signal of the pressure sensor 11 detected according to the operation amount of the pilot valve 16 for performing the bucket dump. The set value BV1a corresponds to the value of the pressure signal of the pressure sensor 9 corresponding to the operation amount of the pilot valve 12 at the start of the trajectory control which is empirically obtained during the normal front drive, and the normal front A value corresponding to the value of the pressure signal of the pressure sensor 10 corresponding to the operation amount of the pilot valve 14 at the time of starting the trajectory control obtained empirically during driving is set. Further, as AV1a, the one corresponding to the value of the pressure signal of the pressure sensor 11 corresponding to the operation amount of the pilot valve 16 at the time of starting the trajectory control, which is empirically obtained during normal front driving, is set as a set value KV1a in the storage unit in advance. I remember it.

The condition 2a is the pressure sensor 9 detected according to the operating speed of the pilot valve 12 for raising the boom.
Corresponding to the set value corresponding to the change amount of the pressure signal per unit time and the change amount per unit time of the pressure signal of the pressure sensor 10 detected according to the operation speed of the pilot valve 14 that implements the arm cloud. The present invention relates to a set value and a set value corresponding to the amount of change per unit time of the pressure signal of the pressure sensor 11 detected according to the operating speed of the pilot valve 16 that performs the bucket dump. The set value B corresponding to the change amount per unit time of the pressure signal of the pressure sensor 9 corresponding to the operation speed of the pilot valve 12 at the start of the trajectory control is obtained.
As S2a, the set value AS2a corresponding to the amount of change per unit time of the pressure signal of the pressure sensor 10 corresponding to the operation speed of the pilot valve 14 at the time of starting the trajectory control obtained empirically during normal front driving is set. As the set value KS2a, a value corresponding to the change amount per unit time of the pressure signal of the pressure sensor 11 corresponding to the operation speed of the pilot valve 16 at the time of starting the trajectory control, which is empirically obtained during normal front driving, is set as the set value KS2a. Each is stored in advance in the storage unit.

In the case of "earth and sand carrying work" for carrying the earth and sand excavated to the main body 18 side as shown by the arrow 56 in FIG.
Normally, the operator should slowly raise the boom, arm cloud, and bucket dump so that the earth and sand stored in the bucket 21 do not spill.
Start moving the operation levers 2, 14 and 16. Therefore, the operation form of the front at the start of this "sand transportation work" can be considered as an empirically almost unique operation form, and the above-mentioned set values BV1a, AV1a, KV1a, B are set.
S2a, AS2a, and KS2a are effective as the locus control start operation information stored in advance.

As the condition β1 stored in the storage unit of the controller 25 described above, the following condition Ia and condition II are set.
a and condition IIIa are included. The condition Ia is detected when the setting value corresponding to the value of the pressure signal of the pressure sensor 9 detected when the pilot valve 12 that implements the boom raising is neutral and the pilot valve 14 that implements the arm crowd is neutral. The setting value corresponding to the value of the pressure signal of the pressure sensor 10 and the setting value corresponding to the value of the pressure signal of the pressure sensor 11 detected when the pilot valve 16 that implements the bucket dump is neutral, Pilot valve 12
Is the set value BV01a corresponding to the value of the pressure signal of the pressure sensor 9 when the operation amount is 0 and the pressure of the pressure sensor 10 when the pilot valve 14 is neutral and the operation amount is 0. A value corresponding to the value of the signal is set as the set value AV01a, and a value corresponding to the value of the pressure signal of the pressure sensor 11 when the pilot valve 16 is in the neutral state and the manipulated variable is 0 is set value KV01a in the storage unit. I remember it.

The condition IIa is a set value corresponding to the value of the pressure signal of the pressure sensor 9 detected according to the operation amount of the pilot valve 12 for raising the boom, and the operation amount of the pilot valve 14 for performing the arm crowding. The set value corresponding to the value of the pressure signal of the pressure sensor 10 detected accordingly, and the set value corresponding to the value of the pressure signal of the pressure sensor 11 detected according to the operation amount of the pilot valve 16 for performing the bucket dump. A value corresponding to the value of the pressure signal of the pressure sensor 9 corresponding to a relatively large operation amount, which exceeds the operation amount of the pilot valve 12 that is empirically considered during normal trajectory control, is set as the set value BVLa. A pressure signal of the pressure sensor 10 corresponding to a relatively large operation amount, which exceeds the operation amount of the pilot valve 14 which is empirically considered during normal trajectory control. Those corresponding to the value, setting value AVL
As a, a value corresponding to the value of the pressure signal of the pressure sensor 11 corresponding to a relatively large operation amount that exceeds the operation amount of the pilot valve 16 that is empirically considered during normal trajectory control is stored as a set value KVLa. It is stored in the department in advance.

Condition IIIa is a set value corresponding to the amount of change per unit time of the pressure signal of the pressure sensor 9 detected according to the operating speed of the pilot valve 12 for raising the boom, and the pilot for executing the arm crowd. A set value corresponding to the amount of change per unit time of the pressure signal of the pressure sensor 10 detected according to the operating speed of the valve 14, and a pressure sensor detected according to the operating speed of the pilot valve 16 that implements the bucket dump. The pressure sensor 9 corresponds to a set value corresponding to the amount of change in the pressure signal of unit 11 per unit time, and corresponds to an operating speed sufficiently higher than the operating speed of the pilot valve 12 which is empirically considered during normal trajectory control.
What corresponds to the change amount of the pressure signal of
As the set value BSLa, a value corresponding to the amount of change in the pressure signal of the pressure sensor 10 per unit time, which corresponds to a speed sufficiently higher than the operation speed of the pilot valve 14 which is empirically considered during normal trajectory control, is set. , Set value ASL
Further, as a, a value corresponding to a change amount per unit time of the pressure signal of the pressure sensor 11 corresponding to a speed sufficiently higher than the operation speed of the pilot valve 16 which is empirically considered in normal trajectory control is set. The values KSLa are stored in the storage unit in advance.

Here, in the case of the trajectory control in the "earth and sand transportation work" in which the bucket 21 containing the earth and sand is moved in the direction of the main body 18, generally when the operator does not perform the trajectory control, the operator operates the pilot valve 12 for raising the boom. The neutralization is performed, the pilot valve 14 that performs arm crowding is neutralized, and the pilot valve 16 that performs bucket dumping is neutralized. Alternatively, in order to hold the front at a high position, the boom 2
3 is greatly raised, and the arm 22 and the bucket 21 are largely rotated. Alternatively, the operator
When not considering the trajectory control, the boom 23 is empirically
Alternatively, the arm 22 or the bucket 21 is moved at a high operating speed. Therefore, the operation form of the front in the case where the trajectory control in this “earth and sand transportation work” is not performed can be empirically determined as described above, and the set values BV01a, AV01a, KV01 described above are set.
a, BVLa, AVLa, KVLa, BSLa, ASL
a and KSLa are effective as trajectory control stop operation information stored in advance.

The operation of the second embodiment constructed as described above is almost the same as that of the first embodiment described above. This second
The operation of this embodiment will be described below with reference to the flow chart of FIG.

First, when the control by the operation of the controller 25 is started, the pressure signals of the pressure sensors 9, 10, 11 and the angle signals of the boom angle sensor 24, the arm angle sensor 19, and the bucket angle sensor 20 are input to the controller 25. To be done.

Now, as illustrated in step S1, the operator operates the pilot valves 12, 14, 16 to drive the boom cylinder 23a, the arm cylinder 22a, and the bucket cylinder 21a as appropriate to carry out normal general work, for example, the bucket 21. It is assumed that excavation work is performed by cutting the blade edge of into the ground.

As illustrated in step S2, the controller 25 determines whether or not the operation lever pattern of the pilot valves 12, 14, 16 satisfies a predetermined condition α1 (condition for starting earth and sand transport work / trajectory control). It That is, in the calculation unit of the controller 25, the pressure signal output from the pressure sensor 9 is equal to the set value BV1a at the time of starting the trajectory control of the condition 1a described above stored in the storage unit,
At the same time, the pressure signal output from the pressure sensor 10 is equal to the set value AV1a at the time of starting the trajectory control of the above-described condition 1a stored in the storage unit, and at the same time, the pressure signal output from the pressure sensor 11 is The set value KV1 at the time of starting the trajectory control of the above-mentioned condition 1a stored in the storage unit
It is determined whether it is equal to a. Further, in the calculation unit of the control 25, the change amount of the operation speed of the operation lever of the pilot valve 12, that is, the change amount of the pressure signal of the pressure sensor 9 per unit time is stored in the storage unit. Is equal to the set value BS2a at the start of locus control, and at the same time, the change amount of the operation speed of the operation lever of the pilot valve 14, that is, the change amount of the pressure signal of the pressure sensor 10 per unit time is stored in the storage unit. The change amount of the operation speed of the operation lever of the pilot valve 16, that is, the change amount of the pressure signal of the pressure sensor 11 per unit time is equal to the set value AS2a at the time of starting the trajectory control of the condition 2a described above. It is determined whether or not it is equal to the set value KS2a at the start of the trajectory control of the condition 2a stored in the above.

In this case, since ordinary general work is performed, the above condition α1, that is, condition 1a, condition 2 is satisfied.
Since neither a is satisfied, the trajectory control exemplified in step S3 is not executed, and the process returns to step S1. At this time, the controller 25
Outputs a control signal during normal operation from the proportional solenoid valves 4, 5, 7, and 8. Thereby, for example, the proportional solenoid valve 4 is controlled so as to form an open state that does not affect the supply of pilot pressure from the pilot valve 12 to the shuttle valve 2, and the proportional solenoid valve 8 is controlled from the pilot valve 16. The proportional solenoid valve 5 is controlled to form an open state that does not affect the supply of pilot pressure to the shuttle valve 3, and the proportional solenoid valve 5 is in a closed state that restricts the supply of pilot pressure from the pilot hydraulic power source 13 to the shuttle valve 2. The proportional solenoid valve 7 is controlled to form a closed state that restricts the supply of pilot pressure from the pilot hydraulic pressure source 15 to the shuttle valve 3.

As a result, a pilot pressure corresponding to the operation amount of the pilot valve 12 is given to the pilot chamber of the boom raising spool A of the control valve 1 via the proportional solenoid valve 4 and the shuttle valve 2, and this boom raising spool is provided. A
Is driven, and the boom cylinder 23a is operated by the pressure oil discharged from the main hydraulic pump (not shown), and the boom 23 is driven accordingly. Further, a pilot pressure according to the operation amount of the pilot valve 14 is given to the pilot chamber of the arm cloud spool B of the control valve 1, the arm cloud spool B is driven, and the pressure discharged from the main hydraulic pump (not shown) is supplied. Arm cylinder 22 with oil
a operates, and the arm 22 drives accordingly. Further, a pilot pressure corresponding to the operation amount of the pilot valve 16 is given to the pilot chamber of the bucket dump spool C of the control valve 1, the bucket dump spool C is driven, and the pressure discharged from a main hydraulic pump (not shown) is supplied. The bucket cylinder 21a is operated by the oil, and the bucket 21 is driven accordingly. That is, it is possible to carry out ordinary general work such as excavation work in accordance with the operation of the pilot valves 12, 14, 16 by the operator.

Unlike the general work described above, the operator operates the pilot valves 12, 14, 16 in consideration of the trajectory control for carrying out the "sand transport work" illustrated in FIG. Figure 1 with it stored in
When the front is driven slightly as indicated by the arrow 56 of 0, the determination in step S2 described above is satisfied. That is, in the calculation unit of the controller 25, the pressure signal output from the pressure sensor 9 is equal to the set value BV1a at the start of trajectory control stored in the storage unit, and at the same time, the pressure signal output from the pressure sensor 10 is , When the trajectory control start set value AV1a stored in the storage unit is equal to the pressure signal output from the pressure sensor 11 at the same time as the trajectory control start set value KV1a stored in the storage unit. To be judged. Alternatively, the amount of change in the pressure signal of the pressure sensor 9 per unit time is equal to the set value BS2a at the start of trajectory control stored in the storage unit, and at the same time, the amount of change in the pressure signal of the pressure sensor 10 per unit time. Is equal to the set value AS2a at the start of trajectory control stored in the storage unit, and at the same time, the amount of change in the pressure signal of the pressure sensor 11 per unit time is set at the start of trajectory control stored in the storage unit. It is determined to be equal to the value KS2a.

As a result, the trajectory control of the "earth and sand transportation work" is executed as illustrated in step S3. At this time, a control signal for closing the pilot conduit between the pilot valve 12 and the shuttle valve 2 is output from the output section of the controller 25 to the proportional solenoid valve 4, and the proportional solenoid valve 8 is output from the output section. In addition, a control signal for closing the pilot pipe between the pilot valve 16 and the shuttle valve 3, for example, is output, and the proportional solenoid valve 5 is output from the output section.
, A control signal for appropriately opening the pilot line between the pilot hydraulic power source 13 and the shuttle valve 2 is output,
At the same time, a control signal for opening the pilot line between the pilot hydraulic power source 15 and the shuttle valve 3 as appropriate is output. That is, the operator operates the pilot valve 14 to supply the pressure oil to the pilot chamber of the arm cloud spool B to drive the arm cloud spool B, in consideration of the trajectory control of the “sand transport work”. The arm cylinder 2 is driven by pressure oil discharged from a main hydraulic pump (not shown).
2a is actuated and the boom angle sensor 24, during the operation of clouding the arm 22 as shown by the arrow 56 in FIG.
An angle signal is output from each of the arm angle sensor 19 and the bucket angle sensor 20 and input to the controller 25. The calculation unit of the controller 25 uses these sensors 2
Based on the angle signals output from 4, 19, and 20, the rotation angle of the boom 23 and the rotation angle of the bucket 21 for the trajectory control of the "sand transportation work" corresponding to the movement of the arm 22 are calculated, A control signal corresponding to the calculated value of the rotation angle of the boom 23 is output to the proportional solenoid valve 5, and a control signal corresponding to the calculated value of the rotation angle of the bucket 21 is output to the proportional solenoid valve 7. Along with this, the pilot pressure of the pilot hydraulic pressure source 13 is given to the pilot chamber of the boom raising spool A via the proportional solenoid valve 5 and the shuttle valve 2, and the pilot valve 1
The boom raising spool A is driven regardless of the operation of 2.
The boom cylinder 23a is driven to expand by the pressure oil discharged from the main hydraulic pump (not shown), and the pilot pressure of the pilot hydraulic power source 15 is transferred to the bucket dump spool C via the proportional solenoid valve 7 and the shuttle valve 3. The bucket cylinder 2 is driven by the pressure oil that is supplied to the pilot chamber, drives the bucket dump spool C regardless of the operation of the pilot valve 16, and is discharged from a main hydraulic pump (not shown).
1a is driven, and the boom 23 and the bucket 2 are driven by these.
1 rotates following the movement of the arm 22 to perform a desired “sand and sand transportation work”, that is, “sediment and sand transportation work” in which the bucket 21 storing the sand and sand is moved in the direction of arrow 56 in FIG. 10.
Can be done. In this way, the pilot valve 1
Along with the operation of 2, 14 and 16, it is possible to naturally shift from the normal general work to the trajectory control of the “sand transportation work”.

After the "execution of locus control" in step S3 of FIG. 2 described above, as shown in step S4, the operation lever pattern of the pilot valves 12, 14, 16 is set to a predetermined condition β1 ( (Conditions for sediment transport work and trajectory control suspension)
The controller 25 determines whether or not the above conditions are satisfied. That is, in the calculation unit of the controller 25, whether the pressure signal output from the pressure sensor 9 is equal to the neutral setting value BV01a stored in the storage unit described above for the condition Ia, or output from the pressure sensor 10. Whether the pressure signal is equal to the neutral setting value AV01a stored in the storage unit, or whether the pressure signal output from the pressure sensor 10 is stored in the storage unit. Condition Ia Neutral setting value KV01a
Is determined to be equal to. Alternatively, whether or not the pressure signal of the pressure sensor 9 related to boom raising is equal to or higher than the set value BVLa corresponding to the relatively large operation amount of the above-mentioned condition IIa stored in the storage unit, or the pressure sensor 10 related to the arm cloud. Whether the pressure signal is equal to or more than the set value AVLa corresponding to the relatively large operation amount of the above-mentioned condition IIa stored in the storage unit, or the pressure signal of the pressure sensor 11 related to the bucket dump is stored in the storage unit. It is determined whether or not it is equal to or larger than the set value KVLa corresponding to the relatively large operation amount of the condition IIa mentioned above. Alternatively, the amount of change per unit time of the pressure signal of the pressure sensor 9 related to raising the boom is stored in the storage unit under the condition IIIa described above.
Set value B corresponding to the fast operation speed of the pilot valve 12
Whether or not it is SLa or more, or the amount of change in the pressure signal of the pressure sensor 10 related to the arm cloud per unit time is set value ASLa corresponding to the fast operation speed of the pilot valve 14 of the above-mentioned condition IIIa stored in the storage unit. Whether or not the above, or the pressure sensor 11 related to the bucket dump
It is determined whether or not the amount of change in the pressure signal per unit time is equal to or greater than the set value KSLa corresponding to the high operating speed of the pilot valve 16 of the above-mentioned condition IIIa stored in the storage unit.

If it is assumed that the trajectory control of the "earth and sand transportation work" is being performed, the determination at step S4 is not satisfied, the procedure returns to step S3, and the trajectory control described above is continued.

When the determination in step S4 is satisfied, the situation is such that the trajectory control is stopped, and the procedure returns to step S1 to shift to the normal general work described above. That is, from the controller 25 to the proportional solenoid valve 4,
A control signal at the time of normal operation is output to 5, 7, and 8, for example, the proportional solenoid valve 4 is controlled so as to form an open state that does not affect the supply of pilot pressure from the pilot valve 12 to the shuttle valve 2. , Proportional solenoid valve 4 is pilot valve 1
2 is controlled so as to form an open state that does not affect the supply of pilot pressure from 2 to the shuttle valve 2, and the proportional solenoid valve 8 does not affect the supply of pilot pressure from the pilot valve 16 to the shuttle valve 3. The proportional solenoid valve 5 is controlled so as to form an open state, and the pilot hydraulic source 1
3 is controlled to form a closed state in which the supply of pilot pressure from the shuttle valve 2 to the shuttle valve 2 is controlled, and the proportional solenoid valve 7 is in a closed state in which the supply of pilot pressure from the pilot hydraulic pressure source 15 to the shuttle valve 3 is restricted. Controlled to form.

As a result, a pilot pressure corresponding to the manipulated variable of the pilot valve 12 is applied to the pilot chamber of the boom raising spool A of the control valve 1, the boom raising spool A is driven, and a main hydraulic pump (not shown) is operated. The boom cylinder 23a is operated by the discharged pressure oil, and the boom 23 is driven accordingly. Further, a pilot pressure according to the operation amount of the pilot valve 14 is given to the pilot chamber of the arm cloud spool B of the control valve 1, the arm cloud spool B is driven, and the pressure discharged from the main hydraulic pump (not shown) is supplied. The arm cylinder 22a is activated by the oil, and the arm 22 is driven accordingly. Further, a pilot pressure corresponding to the operation amount of the pilot valve 16 is applied to the pilot chamber of the bucket dump spool C of the control valve 1, the bucket dump spool C is driven, and the pressure discharged from the main hydraulic pump (not shown) is supplied. Bucket cylinder 21a with oil
Is activated, and the bucket 21 is driven accordingly. In this way, the trajectory control of the "sand transportation work" can be naturally shifted to the ordinary general work such as excavation work in accordance with the operation of the pilot valves 12, 14, 16 by the operator.

Also in the second embodiment thus constructed, the boom 23, the arm 22 and the bucket by the operator's pilot valves 12, 14 and 16 which are usually carried out are similar to the first embodiment described above. In accordance with the driving operation of 21, that is, the front driving operation, it is possible to naturally shift from the normal general work to the “earth and sand transport work” trajectory control without any special button operation. It is possible to secure excellent operability when shifting to the trajectory control of this “sand and sand transportation work” without giving the operator the troublesomeness and discomfort. Also, from the trajectory control of such "sand transport work" to normal normal work naturally,
It is possible to make a transition without giving the operator a feeling of inconvenience and a feeling of strangeness, and it is possible to secure excellent operability even when shifting from the trajectory control of this “sand transport work” to general work.

FIG. 4 is a diagram showing another example of the “leveling work” carried out by the hydraulic excavator cited as the construction machine to which the present invention is applied, and FIG. 5 shows the configuration of the third embodiment of the present invention. FIG.

The structural difference between the third embodiment shown in FIG. 5 and the first embodiment shown in FIG. 1 is that the control valve 1 has a boom lowering spool D and an arm dump spool E. And a pilot pressure is supplied from the shuttle valve 2 to the pilot chamber of the boom lowering spool D,
The point is that the pilot pressure generated by the pilot valve 14 is supplied to the pilot chamber of the arm dump spool E. In the third embodiment, as shown by the arrow 52 in FIG. 4, the trajectory control is started from the state where the bucket 21 is located on the side closer to the main body 18 of the hydraulic excavator, and the blade edge of the bucket 21 is separated from the main body 18. It is designed to move in the direction and carry out "leveling work".

That is, during normal general work, a control signal at the time of normal operation is output from the output part of the controller 25 to the proportional solenoid valves 4 and 5. For example, the proportional solenoid valve 4 transfers from the pilot valve 12 to the shuttle valve 2. The proportional solenoid valve 5 is controlled so as to form an open state that does not affect the supply of pilot pressure.
It is controlled to form a closed state that restricts the supply of pilot pressure to the valve. Thereby, the pilot pressure corresponding to the operation amount of the pilot valve 12 is proportional to the solenoid valve 4 and the shuttle valve 2.
Is supplied to the pilot chamber of the boom lowering spool D of the control valve 1 and driven by the boom lowering spool D, and the boom cylinder 23a is operated by the pressure oil discharged from the main hydraulic pump (not shown). Along with this, the boom 23 is driven. Further, a pilot pressure according to the operation amount of the pilot valve 14 is applied to the pilot chamber of the arm dump spool E of the control valve 1, the arm dump spool E is driven, and the pressure discharged from a main hydraulic pump (not shown) is supplied. Arm cylinder 22 with oil
a operates, and the arm 22 drives accordingly. That is, normal general work such as excavation work according to the operation of the pilot valves 12 and 14 by the operator can be performed.

Further, in consideration of the trajectory control of the "leveling work", the operator operates the pilot valves 12 and 14 to position the front at the position shown by the broken line in FIG.
When it is driven slightly in the direction of arrow 52 of FIG.
The determination in step S2 of the flowchart in FIG.
Moving to 3, the trajectory control is executed. Note that the judgment condition α,
β and each set value BV stored in the controller 25
1, AV1, BS2, AS2, BV01, AV01, B
VL, BSL and ASL are the same as those in the first embodiment described above.

In this trajectory control, a control signal for closing the pilot conduit between the pilot valve 12 and the shuttle valve 2, for example, is output from the output section of the controller 25 to the proportional solenoid valve 4, and at the same time, as described above. A control signal for appropriately opening the pilot line between the pilot hydraulic pressure source 13 and the shuttle valve 2 is output from the output part of the above to the proportional solenoid valve 5. That is, the operator operates the pilot valve 14 in consideration of the "leveling work" to supply the pressure oil to the pilot chamber of the arm dump spool E, and the arm dump spool E is driven to drive a main body (not shown). The arm cylinder 22a operates so as to contract by the pressure oil discharged from the hydraulic pump, and the boom angle sensor 24, the arm angle sensor 19, the bucket angle sensor while the arm 22 performs the dumping operation as shown by the arrow 51 in FIG. An angle signal is output from each of 20 and input to the controller 25. The calculation unit of the controller 25 is configured by these sensors 24,
Based on the angle signals output from 9 and 20, the arm 2
The rotation angle of the boom 23 for trajectory control corresponding to the movement of 2 is calculated, and a control signal corresponding to the calculated value is output to the proportional solenoid valve 5. Along with this, the pilot hydraulic power source 13
Is applied to the pilot chamber of the boom lowering spool D via the proportional solenoid valve 5 and the shuttle valve 2, and the boom lowering spool D is driven regardless of the operation of the pilot valve 12, and the main hydraulic pump (not shown) The ejected pressure oil drives the boom cylinder 23a to contract, whereby the boom 23 follows the movement of the arm 22 and descends, so that the desired "leveling work", that is, in the direction of arrow 52 in FIG. Trajectory control of "leveling work" for finishing the ground flat by moving the blade edge of the bucket 21 can be performed. Thus, even in the third embodiment,
Along with the operation of the pilot valves 12 and 14, it is possible to naturally shift from normal general work to trajectory control.

If the determination at step S4 in the flow chart of FIG. 2 is satisfied and it is conscious of stopping the trajectory control, the procedure returns to step S1 and the controller 25 controls the proportional solenoid valves 4, 5 during normal operation. A signal is output, the proportional solenoid valve 4 is controlled so as to form an open state that does not affect the supply of pilot pressure from the pilot valve 12 to the shuttle valve 2, and the proportional solenoid valve 5 is controlled by the pilot hydraulic power source 13. The shuttle valve 2 is controlled to form a closed state that restricts the supply of pilot pressure to the shuttle valve 2. As a result, a pilot pressure corresponding to the operation amount of the pilot valve 12 is applied to the pilot chamber of the boom lowering spool D of the control valve 1, the boom lowering spool D is driven and discharged from a main hydraulic pump (not shown). The boom cylinder 23a is operated by the pressure oil, and the boom 23 is driven. Further, a pilot pressure according to the operation amount of the pilot valve 14 is applied to the pilot chamber of the arm dump spool E of the control valve 1, the arm dump spool E is driven, and the pressure discharged from a main hydraulic pump (not shown) is supplied. The arm cylinder 22a is activated by the oil, and the arm 22 is driven accordingly. In this way, the trajectory control of the "leveling work" can be naturally shifted to the normal general work such as excavation work in accordance with the operation of the pilot valves 12 and 14 by the operator. Like the first embodiment described above, the third embodiment configured in this manner also has excellent operability without causing the operator any discomfort or discomfort during the transition between the trajectory control and the general work. Can be secured.

FIG. 6 is a diagram showing the configuration of the fourth embodiment of the present invention. In the fourth embodiment, the arrangement of the proportional solenoid valve 4 constituting the flow rate control means is different from that of the first embodiment. That is, the proportional solenoid valve 4 is arranged in the middle of the pilot line connecting the shuttle valve 2 and the pilot chamber of the boom raising spool A of the control valve 1.

In the fourth embodiment, during normal general work, for example, a control signal for opening the proportional solenoid valve 4 to the proportional solenoid valve 4 is output from the output section of the controller 25 to the proportional solenoid valve 4. 5, a control signal for closing the proportional solenoid valve 5 is output, and the pilot pressure according to the operation amount of the pilot valve 12 is transmitted via the shuttle valve 2 and the proportional solenoid valve 4 to the boom lowering spool of the control valve 1. A
Given to the pilot room. As a result, the boom 23 and the arm 22 corresponding to the operation amounts of the pilot valves 12 and 14
Can be driven and general work can be performed.

Further, in the trajectory control, for example, a control signal is output from the output section of the controller 25 to the proportional solenoid valves 4 and 5 so that they have the same opening area. In addition, the control signal drives the boom 23 so as to follow the calculation value obtained by the calculation unit of the control valve 1, that is, the drive of the arm 22 by the operation of the pilot valve 14, and performs a desired trajectory control. It corresponds to the calculated value. The fourth embodiment configured in this way also achieves the same effects as the first embodiment described above.

FIG. 7 is a diagram showing the configuration of a fifth embodiment of the present invention which is a modification of the above-described first embodiment. The fifth embodiment is different from the first embodiment in that
As a front detecting device for detecting the front posture, a boom stroke sensor 28 for detecting a stroke of a boom cylinder 23a for operating the boom 23, and an arm stroke sensor 26 for detecting a stroke of an arm cylinder 22a for operating the arm 22. , Bucket 2
1 and a bucket stroke sensor 27 for detecting the stroke of the bucket cylinder 21a for operating the No. 1 operation.

As in the first embodiment, the boom angle sensor 24 for detecting the front posture is replaced by a boom stroke sensor 28, the arm angle sensor 19 is replaced by an arm stroke sensor 26 and a bucket angle sensor 20. Even if the stroke sensor 27 for a bucket is provided in the above, since each stroke corresponds to the rotation angle of the corresponding front member, the signals output from the stroke sensors 28, 26, 27 are Based on the above, the rotation angle of each of the boom 23, the arm 22, and the bucket 21 can be obtained by the calculation unit of the controller 25, and the arm cloud can be made to follow the operation of the pilot valve 14 as in the first embodiment. The proportional solenoid valve 5 can be driven according to the above-obtained angle, and the trajectory control of the "leveling work" It can be realized.

Also in the fifth embodiment having the above-mentioned structure, the same effect as that of the first embodiment can be obtained.

FIG. 8 is a diagram showing the configuration of a sixth embodiment of the present invention which is a modification of the above-described second embodiment. In the sixth embodiment, as an operating device for instructing the flow rate supplied to the hydraulic cylinder that drives the front, instead of the pilot valves 12, 14, 16 in the first embodiment, electric lever devices 30, 31, 32 is provided. The electric lever device 30 commands the flow rate supplied to the boom cylinder 23a, the electric lever device 31 commands the flow rate supplied to the arm cylinder 22a, and the electric lever device 32 commands the flow rate supplied to the bucket cylinder 21a. .

As a flow rate control means for controlling the flow rate supplied to the hydraulic cylinder, a pilot hydraulic pressure source 33,
A proportional solenoid valve 34, which is arranged in a pilot line between the pilot hydraulic power source 33 and the boom raising spool A and is driven according to a signal output from an output unit of the controller 25, a pilot hydraulic power source 33, and an arm cloud. Between the pilot hydraulic pressure source 33 and the bucket dump spool C, and a proportional solenoid valve 35 that is arranged in a pilot pipe line between the pilot hydraulic pressure source 33 and the spool B for driving and is driven according to a signal output from the output unit of the controller 25. And a proportional solenoid valve 36 which is arranged on the road and is driven according to a signal output from the output section of the controller 25.

It should be noted that a signal corresponding to the lever operation amount of the electric lever device 30, 31, 32 is input to the arithmetic unit via the input unit of the controller 25, and the arithmetic unit can recognize the value of the corresponding signal. Therefore, in the sixth embodiment, the calculation unit of the controller 25 also serves as the operation amount detection device that detects the operation amount of the operation device, that is, the electric lever devices 30, 31, 32.

Further, the storage unit of the controller 25 stores a condition α1b similar to the condition α1 for judging the start of the trajectory control of the “sand transport work” in the second embodiment described above.
Then, a condition β1b similar to the condition β1 for determining the stop of the trajectory control is stored.

The above condition α1b is the following condition 1ab
And Condition 2ab are included. The condition 1ab is a set value corresponding to the lever operation amount of the electric lever device 30 for performing the boom raising, and the electric lever device 3 for performing the arm crowding.
1 is a set value corresponding to the lever operation amount and a set value corresponding to the operation amount of the electric lever device 32 for carrying out the bucket dump. A value corresponding to the lever operation amount of the lever device 30 is set as a set value BV1ab,
Further, a value corresponding to the lever operation amount of the electric lever device 31 at the time of starting the trajectory control which is empirically obtained during the normal front driving is set as the set value AV1ab, and when the trajectory control is started empirically obtained during the normal front driving. A value corresponding to the lever operation amount of the electric lever device 32 is stored as a set value KV1ab in the storage unit in advance.

The condition 2a is a set value corresponding to the operation speed of the electric lever device 30 for raising the boom, a set value corresponding to the operation speed of the electric lever device 31 for performing the arm crowding, and a bucket dump. It relates to a set value corresponding to the operation speed of the electric lever device 32, and a value corresponding to the operation speed of the electric lever device 30 at the start of trajectory control obtained empirically during normal front driving is set as the set value BS2ab. , The set value AS2 corresponding to the operation speed of the electric lever device 31 at the start of the trajectory control obtained empirically during the normal front drive.
Further, as ab, a set value KS2ab corresponding to the operating speed of the electric lever device 32 at the start of the trajectory control, which is empirically obtained during normal front driving, is stored in advance in the storage unit.

The conditions β1b stored in the storage unit of the controller 25 described above include the following conditions Iab, IIab, and IIIab. The condition Iab is a set value corresponding to when the electric lever device 30 for raising the boom is neutral, a set value corresponding to when the electric lever device 31 for performing the arm crowd is neutral, and an electric value for performing the bucket dump. The electric lever device 30 relates to a set value corresponding to the neutral position of the lever device 32.
Is a set value BV01ab that corresponds to a value when the operation amount is 0 and is neutral, and a set value AV01ab that corresponds to a value when the electric lever device 31 is neutral and the operation amount is 0. Further, a value corresponding to the value when the electric lever device 32 is neutral and the operation amount becomes 0 is stored in advance in the storage unit as the set value KV01ab.

Condition IIab is a set value corresponding to the operation amount of the electric lever device 30 for raising the boom, a set value corresponding to the operation amount of the electric lever device 31 for performing the arm crowding, and an electric lever for performing the bucket dump. Device 32
The electric lever device 3 relating to the set value corresponding to the operation amount of
An electric lever device 31 that is empirically considered in normal trajectory control is used as a set value BVLab that corresponds to a value corresponding to a relatively large operation amount that exceeds 0 operation amount.
That corresponds to a value corresponding to a relatively large operation amount that exceeds the operation amount of the electric lever device 32 that is empirically considered during normal trajectory control. The set value KVLab corresponding to the value corresponding to the quantity is stored in the storage unit in advance.

The condition IIIab is a set value corresponding to the operation speed of the electric lever device 30 for raising the boom, a set value corresponding to the operation speed of the electric lever device 31 for performing the arm crowding, and a bucket dump. The set value B corresponds to the set value corresponding to the operation speed of the electric lever device 32.
As the SLab, a value corresponding to the operating speed of the electric lever device 31 which is empirically considered in the normal trajectory control is set as the set value ASLab. The one corresponding to the operation speed is stored in advance in the storage unit as the set value KSLab.

In the sixth embodiment constructed as described above, a control signal corresponding to the lever operation amount of the electric lever device 30 is applied to the proportional solenoid valve 34 during general work, and the proportional solenoid valve 34 is operated by the proportional solenoid valve 34. The opening amount is set in accordance with the lever operation amount of 30 and the pressure oil of the pilot hydraulic pressure source 33 is supplied to the pilot chamber of the boom raising spool A of the control valve 1 via the proportional solenoid valve 34, and the boom cylinder 23a is operated. Then, the boom 23 rotates. Similarly,
A control signal according to the lever operation amount of the electric lever device 31 is given to the proportional solenoid valve 35, and the proportional solenoid valve 35 has an opening amount according to the lever operation amount of the electric lever device 31,
The pressure oil of the pilot hydraulic pressure source 33 is supplied to the pilot chamber of the arm cloud spool B of the control valve 1 via the proportional solenoid valve 35, and the arm cylinder 22a.
Is activated and the arm 22 is rotated. In addition, the control signal corresponding to the lever operation amount of the electric lever device 32 is a proportional solenoid valve 3
6, the proportional solenoid valve 36 is connected to the electric lever device 3
The amount of opening of the pilot hydraulic pressure source 33 is supplied to the pilot chamber of the bucket spool C of the control valve 1 via the proportional solenoid valve 36, and the bucket cylinder 21a operates. The bucket 21 rotates. That is, the electric lever devices 30, 3
Boom 23 and arm 2 according to the lever operation amount of 1, 32
2. The bucket 21 can be driven to perform general work such as excavation work.

Unlike such general work, the operator is conscious of the trajectory control for carrying out the "earth and sand carrying work" illustrated in FIG. 10, and the operator operates the electric lever devices 30, 31, and 3.
2 is operated to drive the front slightly as shown by the arrow 56 in FIG. 10 while the excavated earth and sand are stored in the bucket 21, the determination corresponding to step S2 in the flowchart in FIG. 2 described above is satisfied. . That is, in the calculation unit of the controller 25, the operation signal of the electric lever device 30 is stored in the storage unit, and the set value B at the start of the trajectory control is set.
V1ab, at the same time, the operation signal of the electric lever device 31 is equal to the set value AV1ab at the time of starting the trajectory control stored in the storage unit, and at the same time, the electric lever device 3
It is determined that the operation signal No. 2 is equal to the set value KV1ab at the start of the trajectory control stored in the storage unit. further,
The operation speed of the electric lever device 30 is equal to the set value BS2ab at the start of trajectory control stored in the storage unit, and at the same time, the operation speed of the electric lever device 31 is equal to the set value BS2ab at the start of trajectory control stored in the storage unit. Equal to the set value AS2ab,
At the same time, it is determined that the operating speed of the electric lever device 32 is equal to the set value KS2ab at the start of the trajectory control stored in the storage unit.

As a result, the trajectory control of the "earth and sand transportation work" is executed as illustrated in the step S3 of FIG. At this time, the operator operates the electric lever device 31 for the arm while paying attention to the trajectory control of the "sand transportation work", and outputs a control signal from the output part of the controller 25 to the proportional solenoid valve 35 to generate the pilot hydraulic power source. Operation of supplying pilot oil of 33 to the pilot chamber of the spool B for arm cloud through the proportional solenoid valve 35 to operate the arm cylinder 22a and cloud the arm 22 as shown by an arrow 56 in FIG. During the period, angle signals are output from the boom angle sensor 24, the arm angle sensor 19, and the bucket angle sensor 20, and are input to the controller 25. The calculation unit of the controller 25 is configured by the sensors 24, 19, 20.
The rotation angle of the boom 23 and the rotation angle of the bucket 21 for the trajectory control of the "sand transportation work" corresponding to the movement of the arm 22 are calculated based on the angle signal output from the rotation angle of the boom 23. A control signal corresponding to the calculated value of the angle is output from the output section of the controller 25 to the proportional solenoid valve 34, and a control signal corresponding to the calculated value of the rotation angle of the bucket 21 is output from the output section of the controller 25 to the proportional solenoid valve 36. Output. Accordingly, the pilot pressure of the pilot hydraulic pressure source 33 is applied to the pilot chamber of the boom raising spool A via the proportional solenoid valve 34 regardless of the operation of the electric lever devices 30 and 32, so that the boom cylinder 23a is extended. In addition, the pilot pressure of the pilot hydraulic power source 33 is applied to the pilot chamber of the bucket dump spool C via the proportional solenoid valve 36, and drives the bucket cylinder 21a, whereby the boom 23 and the bucket 21 are moved to the arm 22. It is possible to perform a desired "earth and sand transport work", that is, "earth and sand transport work" in which the bucket 21 storing the sand and sand is moved in the direction of arrow 56 in FIG. In this way, the electric lever devices 30, 3
Along with the operations of 1 and 32, it is possible to naturally shift from the normal general work to the trajectory control of the “earth and sand transport work”.

If the judgment corresponding to the step S4 in FIG. 2 is satisfied, it is in the situation where the trajectory control is being stopped, and the normal general work is started. In addition, when the determination corresponding to the step S4 of FIG. 2 is satisfied, the calculation unit of the controller 25 causes the electric lever devices 30, 31, 32.
When the operation lever pattern of No. 1 satisfies the predetermined condition β1b (condition for suspending sediment / trajectory control). That is, the operation amount of the electric lever device 30 is the set value BV0 when the condition Iab described above stored in the storage unit is in the neutral state.
1ab, or the operation amount of the electric lever device 31 is equal to the set value AV01ab in the neutral state of the above-mentioned condition Iab stored in the storage unit, or the operation amount of the electric lever device 32 is equal to the storage unit. This is the case when the condition Iab stored in the above condition is equal to the neutral set value KV01ab. Alternatively, the operation amount of the electric lever device 30 for raising the boom is set value BVL corresponding to the relatively large operation amount of the above-mentioned condition IIab stored in the storage unit.
ab or more, or the operation amount of the electric lever device 31 related to the arm crowd is equal to or more than the set value AVLab corresponding to the relatively large operation amount of the above-mentioned condition IIab stored in the storage unit, or in the bucket dump. This is when the operation amount of the electric lever device 32 is equal to or larger than the set value KVLa corresponding to the relatively large operation amount of the condition IIab described above stored in the storage unit. Alternatively, when the operating speed of the electric lever device 30 for raising the boom is equal to or higher than the set value BSLab of the condition IIIab stored in the storage unit, or when the operating speed of the electric lever device 31 for arm crowding is set to the storage unit. When the operating speed of the electric lever device 32 related to the bucket dump is equal to or higher than the above-mentioned condition IIIab set value ASLa stored in the storage unit, the set value K of the above-mentioned condition IIIab stored in the storage unit is stored.
This is when SLab or more.

In these cases, a control signal for normal operation is output from the output section of the controller 25 to the proportional solenoid valves 34, 35, 36. As a result, as described above, the pilot pressure corresponding to the operation amount of the electric lever device 30 is applied to the pilot chamber of the boom raising spool A of the control valve 1 via the proportional solenoid valve 34, and the boom cylinder 2
3a operates, and the boom 23 is driven accordingly. Further, a pilot pressure corresponding to the operation amount of the electric lever device 31 is applied to the pilot chamber of the arm cloud spool B of the control valve 1 via the proportional solenoid valve 35,
The arm cylinder 22a operates, and the arm 22 is driven accordingly. Further, the pilot pressure corresponding to the operation amount of the electric lever device 32 is given to the pilot chamber of the bucket dump spool C of the control valve 1 via the proportional solenoid valve 36, and the bucket cylinder 21a operates.
Along with this, the bucket 21 is driven. In this way, the trajectory control of the "sand transportation work" can be naturally shifted to the normal general work according to the operation of the electric lever devices 34, 35, 36 by the operator.

The sixth embodiment constructed in this way can also achieve the same effects as the second embodiment.

[0095]

The invention according to claim 1 of the present invention naturally follows a normal general work without a special button operation or the like accompanying the operator's front driving operation which is usually carried out. It is possible to shift to control, without giving the operator any trouble or discomfort in operation,
At the time of shifting to the trajectory control, it is possible to obtain excellent operability as compared with the conventional one.

In addition to the effects described above, the invention according to claim 2 of the present invention allows the trajectory control to shift from the trajectory control to a normal general work naturally without causing the operator to feel bothersome and uncomfortable in operation. Therefore, excellent operability can be obtained even when the trajectory control is shifted to the general work.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a first embodiment of a hydraulic control device for a construction machine according to the present invention.

FIG. 2 is a flowchart showing a processing procedure in a controller provided in the first embodiment shown in FIG.

FIG. 3 is a diagram showing a configuration of a second exemplary embodiment of the present invention.

FIG. 4 is a diagram showing another example of the “leveling work” performed by the hydraulic excavator cited as the construction machine targeted by the present invention.

FIG. 5 is a diagram illustrating a configuration of a third exemplary embodiment of the present invention.

FIG. 6 is a diagram showing a configuration of a fourth exemplary embodiment of the present invention.

FIG. 7 is a diagram showing a configuration of a fifth exemplary embodiment of the present invention.

FIG. 8 is a diagram showing a configuration of a sixth exemplary embodiment of the present invention.

FIG. 9 is a diagram showing “leveling work” performed by the hydraulic excavator cited as the construction machine targeted by the present invention.

FIG. 10 is a diagram showing “earth and sand transportation work” performed by the hydraulic excavator cited as the construction machine targeted by the present invention.

FIG. 11 is a diagram illustrating a problem at the time of the “leveling work” shown in FIG. 9.

FIG. 12 is a diagram showing a problem during the “earth and sand transport work” shown in FIG. 10.

[Explanation of symbols]

1 control valve (flow rate control means) 2 shuttle valve (flow rate control means) 3 shuttle valve (flow rate control means) 4 proportional solenoid valve (flow rate control means) 5 proportional solenoid valve (flow rate control means) 7 proportional solenoid valve (flow rate control means) ) 8 proportional solenoid valve (flow rate control means) 9 pressure sensor (operation amount detection device) 10 pressure sensor (operation amount detection device) 11 pressure sensor (operation amount detection device) 12 pilot valve (operation device) 13 pilot hydraulic power source (flow rate) Control means) 14 Pilot valve (operating device) 15 Pilot hydraulic source (flow control means) 16 Pilot valve (operating device) 18 Main body 19 Arm angle sensor (front angle sensor) [front detection device] 20 Bucket angle sensor (front angle sensor) ) [Front detection device] 21 Bucket (front) 22 Arm (front) 23 Boom ( 24) Boom angle sensor (front angle sensor) [front detection device] 25 Controller 26 Stroke sensor for arm (front detection device) 27 Stroke sensor for bucket (front detection device) 28 Stroke sensor for boom (front detection device) 30 Electric Lever device 31 Electric lever device 32 Electric lever device 33 Pilot hydraulic power source 34 Proportional solenoid valve 35 Proportional solenoid valve 36 Proportional solenoid valve

Claims (2)

[Claims] 1. A front detecting device provided in a construction machine having a front including a boom and an arm, and a hydraulic cylinder driving the front, detecting a posture of the front, and a flow rate supplied to the hydraulic cylinder. A flow rate control means for controlling, an operating device for instructing a flow rate supplied to the hydraulic cylinder, an operation amount detecting device for detecting an operation amount of the operating device, and an output from the operation amount detecting device or the front detecting device. In a hydraulic drive system for a construction machine, which comprises a controller for calculating a signal for outputting a control signal corresponding to the calculated value and outputting the control signal to the flow rate control means, The operation information based on the operation is detected by the storage unit that stores the trajectory control start operation information in advance and the operation amount detection device. And a calculation unit that determines whether or not the actual movable operation information based on the operation amount signal matches the trajectory control start operation information, and the arithmetic unit determines that the actual movable operation information matches the trajectory control start operation information. The hydraulic control device for a construction machine, further comprising: an output unit that outputs a control signal for performing trajectory control to the flow rate control means. 2. The controller detects the operation information based on the operation of the front, which is usually executed when the trajectory control is stopped, as the trajectory control stop operation information, and the operation amount detection device. A calculation unit that determines whether or not the actual movable operation information based on the operation amount signal matches the trajectory control stop operation information, and when the operation unit determines that the actual movable operation information matches the trajectory control stop operation information. The hydraulic control device for a construction machine according to claim 1, further comprising: an output unit that outputs a control signal at the time of normal operation accompanying the suspension of the trajectory control to the flow rate control means.