KR100198500B1 - Device and method for controlling attachment of construction machine - Google Patents

Abstract

In the manual operation, the pilot pressure discharged from the pilot trump 41 is supplied from the manual operation valve 44a or 44b to the main control valve 33 via the electromagnetic switching valve 49a or 49b. At the time of automatic control, the pilot pressure output from the automatic mode selection valve 46 is passed through the electromagnetic proportional valve 48a or 48b and the electromagnetic switching valve 49a or 49b controlled by the controller 21. Supply to the main control valve (33). When limiting the operating range of the work machine during manual operation, the pilot pressure output from the manual operation valve 44a or 44b is converted to the electromagnetic proportional valve 48a or 48b and the electromagnetic switching valve 49a or ( It supplies to the main control valve 33 via 49b). At this time, the pilot pressure is removed by the electromagnetic proportional valve 48a or 48b controlled by the limit signal from the controller 21, and the main control valve 33 is returned to the neutral position.

Description

[Name of invention]

Working device control device of construction machine and its control method

Detailed description of the invention

[Technical Field]

The present invention relates to a work machine control device for a construction machine and a control method thereof.

[Background]

Conventionally, as shown in FIG. 9 in the case of linear excavation in which the excavator is moved by linearly moving the tip of the bucket blade linearly by a hydraulic shovel operated by a hydraulic pilot control valve, as shown in FIG. Similarly, it is common to detect the posture of the work machine link cage by a sensor attached to the joint part of the work machine link cage, and to control the bellows with a microcomputer. When switching between manual operation and automatic mode (automatic linear drilling mode), • An off-operating switching valve is used to switch the pilot hydraulic pressure for operating the main cylinder valve for hydraulic cylinder control.

In this case, by setting the operating range of the working machine in advance in the automatic mode, it is possible to prevent intrusion into the area that limits the operating range of the working machine. It is difficult to do this in view of the switching configuration of the pilot hydraulic pressure.

For this reason, when the operator is operating the work machine, care is taken not to accidentally collide with the surrounding structure or the like, and at the same time, there is a risk or danger of destroying the construction machine itself or the other structure due to the collision.

It is made in view of such a point of this invention, and an object of this invention is to provide the work machine control apparatus of the construction machine which can limit-control the movable range of a work machine, even at the time of manual operation, and its control method.

[Initiation of invention]

The present invention is a work machine control device for a construction machine that controls the hydraulic oil supplied to the hydraulic actuator for operating the work machine by a pilot pressure actuated main control valve, the manual control of the pilot pressure supplied to the main control valve by manual operation A control device for a work machine of a construction machine having a configuration including an operation valve and an electromagnetic rain valve installed in a pilot pressure supply line during manual operation from the manual control valve to the main control valve.

As a result, an electromagnetic proportional valve was installed in the pilot pressure supply line at the time of manual operation from the manual control valve to the main control valve. Therefore, the manual operation pilot pressure is reduced when the work machine approaches the restricted area by manual operation. It can be controlled electrically by electromagnetic proportional valve and can stop working machine by controlling main controller valve in neutral state by electric signal not related to operator's intention, and accidentally collided with surrounding building etc. during manual operation of operator. It is possible to prevent the worry such as to make it, and to ensure the ease and safety of manual operation.

In addition, the present invention, by the manual operation of the pilot pressure supplied to the main control valve in the work machine control device of the construction machine for controlling the hydraulic oil supplied to the hydraulic actuator for operating the working machine by the pilot pressure actuated main control valve. A manual operation valve for controlling, an automatic mode selection valve for selecting a pilot pressure supply line passing through the manual operation valve and a separate pilot pressure supply line at the time of automatic control of the work machine, and one of the manual operation valve and an automatic mode selection valve. An electromagnetic proportional valve for controlling the opening angle of the pilot pressure supplied from the electronic signal, an electromagnetic switching valve for selecting one of the electromagnetic proportional valve and the manual control valve and outputting the pilot pressure to the pilot chamber of the main control valve, and the automatic The mode selection valve, solenoid proportional valve and solenoid switching valve can be controlled by electric signals. A work machine control apparatus for a construction machine according to the configuration provided with the controller, and a working machine and a sensor for detecting the input amount of operation of the work machine to the controller, the manual operation sensors for detecting the input to the manual operation state by the manual operation valves.

Thereby, the automatic control of the work machine which is performed by the manual operation of the work machine by the manual control valve, the pilot pressure supply line which does not go through the manual control valve by the automatic mode selection valve, to the electromagnetic proportional valve, and the manual control valve and the electronic proportional valve It is possible to provide a work machine control device for a construction machine that can realize three functions with the control of the working range limitation of the work machine. Particularly, in the movable range limiting control, the pilot pressure supplied from the manual operation valve is restricted to the operator's intention by entering an operating proportional limit by an electromagnetic proportional valve which controls the opening angle according to the electric signal from the controller. Can be prevented automatically. Further, even if the electromagnetic proportional valve fails due to the combination of the manual operation valve, the electromagnetic proportional valve and the electromagnetic switching valve, the pilot pressure from the manual operation valve can be supplied from the electromagnetic switching valve to the main control valve, thereby enabling manual operation. In addition, it is possible to reliably complete switching between manual operation and automatic control than the electromagnetic switching valve.

Moreover, this invention is the structure provided with the shuttle valve which outputs the pilot pressure supplied from one of them to a electromagnetic proportional valve between a manual operation valve and an automatic mode selection valve. Thus, since a simple and inexpensive shuttle valve is used as the cross valve between the manual operation valve, the automatic mode selection valve, and the electromagnetic proportional valve, the control circuit configuration can be simplified accordingly.

In addition, the present invention is a work machine control method for a construction machine that controls the hydraulic oil supplied to the hydraulic actuator for operating the work machine by a pilot pressure actuated main valve, at a time when the work machine approaches the limited operation range In order to return the main control valve to the neutral position by controlling the pilot pressure supplied to the main control valve controlled by manual operation and reducing the pilot pressure when the work machine reaches its restricted range, the main control valve is removed. It is a control method of work machine of construction machine.

As a result, when the working machine approaches the restricted range, the pressure of the manually operated pilot pressure supplied to the main control valve is reduced and the main control valve is returned to the neutral position, so that the main valve is gradually moved to the neutral position. By gradually braking the inertial load of the work machine, the work machine can be smoothly stopped when the work machine reaches the movable range restriction region, and the occurrence of vibration or the like due to the impact when the work machine is stopped can be prevented.

[Brief Description of Drawings]

1 is a hydraulic circuit diagram showing an example of a work machine control device for a construction machine according to the present invention,

FIG. 2 (a) is a hydraulic circuit diagram showing a circuit state at the time of automatic linear excavation of the work machine control device, and FIG. 2 (b) is a hydraulic circuit diagram showing a circuit state at the time of controlling the working range of the work machine.

3 is a system diagram of a hydraulic excavator equipped with a work machine control device,

4 is an electric and hydraulic circuit diagram showing the overall system configuration of the work machine control device,

FIG. 5 (a) is an explanatory diagram showing the bucket blade end linear excavation mode by the work machine control device, and FIG. 5 (b) is an explanatory diagram showing the operation when the bucket angle holding function is added to the linear excavation mode. ,

6 is an explanatory diagram showing a height limiting state and a sixth limit state of the work machine in the manual operation by the work machine control device.

FIG. 7 is an explanatory diagram showing a state of limiting the work machine at the time of manual operation by the work machine control device.

8 is a flowchart showing a control method of the work machine control device, and FIG. 9 is a circuit diagram showing a conventional work machine control device.

Best Mode for Carrying Out the Invention

Hereinafter, the present invention will be described in detail with reference to the embodiment related to the hydraulic excavator shown in FIGS.

3 is a system configuration diagram of a hydraulic excavator equipped with a work machine control device for a construction machine according to the present invention, in which the upper swing structure 12 is provided on the lower traveling body 11, and the upper swing structure is provided. The float working machine 13 is installed in (12).

The work machine 13 is axially supported on the upper swinging body 12 by the spring cylinder 14bm, and the base end of the boom 15bm is supported by the stick cylinder 14st at the tip of the boom 15bm. The vicinity of the base end of the stick 15st rotated by the shaft is axially supported, and the bucket 15bk rotated by the bucket cylinder 14bk is axially supported on the tip of the stick 15st. The boom cylinder 14bm, the stick cylinder 14st, and the bucket cylinder 14bk are hydraulic actuators for operating the work machine 13.

The rotational angles of the boom 15bm, the stick 15st, and the bucket 15bk are respectively detected by angle sensors 16bm, 16st, 16bk such as resolvers as work machine sensors, and the angle detection signals. Is input to the controller 21 including the microcomputer via the signal converter 17 mounted on the upper swing structure 12.

The controller 21 is connected to an indicator switch panel 22 as an input / output device, and is provided with a pushbutton control switch 23 for starting an automatic control or an engine speed control provided on an operation lever or the like, and an engine speed sensor. Engine pump controller 24 for controlling the engine and pump based on the engine speed detected by 24a, a plurality of pressure sensors 25 for detecting the pressure of the hydraulic circuit driving the work machine 13, Inclination angle sensors 26 and the like for detecting the inclination angle are respectively connected. In addition, a plurality of solenoid valves such as an electromagnetic proportional valve and an electromagnetic switching valve are connected to the output terminal of the controller 21.

4 is a configuration diagram of the whole system of the work machine control device, and various detection signal input lines and solenoid valve drive signal output lines are connected to a controller 21 having an external terminal 28 and a power supply circuit 29. .

In FIG. 4, the solid line is an electric circuit, and the dotted line is a hydraulic circuit. In addition, a large pitch sailing ship is a main hydraulic circuit for each cylinder drive, and a small pitch dotted ship is a pilot hydraulic circuit. The drain circuit is omitted.

The main oil pressure circuit is the boom cylinder 14bm, the stick cylinder 14st, and the bucket cylinder 14bk from the first main pump 32a or the second main pump 32b driven by the engine 31 mounted on the vehicle. The main circuit valve 33bm for the pilot pressure boom, the main control valve 33st for sticks, and the main controller valve 33bk for buckets are respectively provided in the supply circuit of the hydraulic oil supplied to the (1).

Since the boom cylinder 14mb and the stick cylinder 14st require a large flow rate, the electrons for containing to contain two discharge oils of the first main pump 32a and the second main pump 32b in accordance with the required amount. Proportional valves 34mb and 34st are provided for the hydraulic oil supply circuits to the boom cylinder 14mb and the stick cylinder 14st, respectively.

The pilot hydraulic circuit is provided with a pilot pump 41 which is driven at the same time as the main pumps 32a and 32b by the engine 31 mounted in the vehicle, and the discharge line of the pilot pump 41 ( 42), manual operation valve 44bm for proportionally reducing the discharge pressure of the pilot pump by manual operation by the operation levers 43bm, 43st, 43bk for booms, sticks, and buckets; 44st and 44bk are connected.

On the other hand, to control the pilot pressure to the discharge line 45 branched from the discharge line 42 of the pilot pump 41 without passing through the manual operation valves 44bm, 44st, 44bk. An automatic mode selector valve 46 is connected.

Then, shuttle valves 47bm, 47st, 47bk are provided between the output lines of the manual operation 44bm, 44st, 44bk and the output line of the automatic mode selection valve 46. And the pilot pressure supplied from one of the manual operation valves 44bm, 44st, 44bk and the automatic mode selection valve 46 to the output lines of the shuttle valves 47bm, 47st, 47bk. Electronic proportional valves 48bm, 48st, and 48bk for opening angle control in accordance with an electrical signal are connected.

The output lines of the electromagnetic proportional valves 48bm, 48st, and 48bk and the outputs of the manual override valves 44bm, 44st, and 44bk are selected from one of the main control valves 33bm. The electromagnetic switching valves 49bm, 49st, and 49bk output to the pilot chambers of (33st) and (33bk) are connected.

The automatic mode selection valve 46, electromagnetic proportional valves 48bm, 48st, 48bk, and electromagnetic switching valves 49bm, 49st, 49bk are electromagnetically actuated spool valves. The displacement is controlled by the electric signal output from the controller 21.

On the other hand, at the input terminal of the controller 21, the angle sensors 16bm, 16st, 16bk for detecting the operation amount (rotation angle) of each joint portion of the work machine 13 are the signal converter 17. Pressure sensors 25bm, 25st, 25bk, and inputs as a manual operation sensor connected via an input line and detecting a manual operation state by output lines of the manual operation valves 44bm, 44st, and 44bk. The switches 36bm, 36st, and 36bk are connected.

The pressure sensors 25bm, 25st, and 25bk detect analog variations of manual valves 44bm, 44st, and 44bk, while pressure switches 36bm, 36st, and 36bk. 36bk detects the on / off change of the manual operation valves 44bm, 44st, and 44bk.

FIG. 1 is an enlarged view of one hydraulic cylinder control circuit of the work machine control device shown in FIG. 4, using numerals indicated in FIG. 4 in the corresponding parts of FIG. A is added to the corresponding number, and b is attached to the corresponding number on the cylinder short axis side.

In FIG. 1, a pair of manual operation valves 44a which proportionally depressurize the pilot pump discharge pressure by a manual operation by the operation lever 43 to the discharge line 42 of the pilot pump 41. , 44b are connected.

On the other hand, an automatic mode selection valve for controlling the pilot pressure to the discharge line 45 branched from the discharge line 42 of the pilot pump 41 without passing through the manual operation valves 44a and 44b ( 46) is connected. This selector valve 46 is an electromagnetic switching valve.

Shuttle valves 47a and 47b are provided between the output lines of the manual valves 44a and 44b and the output lines of the automatic mode selection valve 46, respectively. The pilot pressure supplied from one of the manual override valves 44a, 44b and the automatic mode selector valve 46 to the output lines of the lines 47b and 47b controls the opening angle according to the electrical signal from the controller 21. Electromagnetic proportional valves 48a and 48b are connected. These proportional valves 48a and 48b are electromagnetic proportional pressure reducing valves.

One of them is selected for the output lines of the electromagnetic proportional valves 48a and 48b and the output lines of the manual override valves 44a and 44b, so that the pilot chamber 33a (33b) of the main control valve 33 is selected. Are connected to the on / off actuating electromagnetic switching valves 49a and 49b for outputting the pilot pressure.

The main control valve 33 returns the spool to the neutral position by return springs provided on both sides of the spool when the pilot pressure is not applied to the two pilot chambers 33a and 33b.

Further, the pressure sensor 25a, 25b for detecting the pilot pressure to each output line of the angle sensor 16 for detecting the rotation angle of the joint of the work machine and the manual operation valves 44a, 44b is a controller ( 21 is connected to the input terminal of the controller 21, and the output terminal of the controller 21 is the automatic mode selector valve 46, the electromagnetic proportional valve 48a, 48b and the electromagnetic switching valve 49a, 49b, respectively. Is connected to the solenoid of.

Next, the operation of the circuit shown in FIG. 1 will be described with reference to FIGS. 1 and 2.

1 generally shows the hydraulic circuit state of the manual operation, and all the solenoid valves 46, 48a, 48b, 49a, and 49b are in an off state. Therefore, the pilot pressure output from the manual operation valve 44a or 44b according to the operation amount of the operation lever 43 passes through the solenoid valve 33 of the main control valve 33 via the electromagnetic switching valve 49a or 49b. ) Or (33b), and hydraulic oil is supplied from the main pump 32 to the head side 14a or the rod side 14b of the hydraulic cylinder 14 via the main control valve 33 of the opening angle according to the pilot pressure. Supplied, the hydraulic cylinder 14 expands and contracts.

FIG. 2 (a) is a straight line excavation while automatically drilling the blade tip of the bucket 15bk as shown in FIG. 5 (a), or as shown in FIG. 5 (b). The hydraulic circuit state at the time of automatic excavation which adds bucket angle retention function to this linear excavation function is shown.

As shown in FIG. 2 (a), at the time of automatic drilling, the automatic mode selection valve 46 and the electromagnetic switching valves 49a and 49b are all on, and the electromagnetic proportional valve 48a or 48b is turned on. Control the pilot pressure supplied from the automatic mode selection valve 46 via the shuttle valve 47a or 47b according to the spool opening angle according to the signal output from the controller 21, and the electromagnetic switching valve 49a or ( The spool direction and the opening angle of the main control valve 33 are controlled via 49b). At this time, since the operation lever 43 is neutral, the pilot pressure is not output from the manual operation valve 44a or 44b.

FIG. 2 (b) shows the hydraulic circuit state in the case of limiting control of the movable range of the work machine 13 during manual operation. As shown in FIG. 6, the work machine 13 at the time of work in the tunnel, etc. ) Shows the hydraulic circuit condition when the ascending height is limited and when the descending depth is limited, or when the reach length of the work machine 13 with respect to the wall is limited as shown in FIG. 7.

As shown in FIG. 2 (b), the automatic mode selector valve 46 is off, the electromagnetic switching valves 49a and 49b are on, and the electromagnetic proportional valve at the time of limiting control of the work machine movable range. 48a) or 48b is a manual operation filer supplied from the manual operation valve 44a or 44b via the shuttle valve 47a or 47b by the spool opening angle according to the signal output from the controller 21; The pressure is controlled, and the spool direction and the opening angle of the main control valve 33 are controlled via the electromagnetic switching valve 49a or 49b.

At this time, for example, when the pilot pressure is supplied from the manual control valve 44a to the pilot chamber 33a of the main control valve 33 and the spool is displaced, the controller 21 transmits an electronic signal from the controller 21 at the time of limiting control of the work machine movable range. The spool of the main control valve 33 is returned to the neutral position by reducing and controlling the solenoid Roy electric signal of the proportional valve 48a to perform a spring return operation as shown in FIG. 1 to depressurize the pilot chamber 33a. Service the work machine.

In the case of the automatic excavation shown in FIG. 2 (a) or the limiting control of the work machine movable range shown in FIG. 2 (b), even when the electromagnetic proportional valves 48a and 48b fail, Pilot pressure from the manual override valves 44a and 44b by a combination of the operating valves 44a and 44b, the electromagnetic switching valves 48a and 48b and the electromagnetic switching valves 49a and 49b. Can be supplied from the electromagnetic switching valves 49a and 49b to the main control valve 33 to continue the manual operation. At this time, all of the solenoid valves have a circuit configuration at the spring return position of each valve that can be operated manually even when it is not energized.

FIG. 8 shows a flowchart for restricting and controlling the lowering operation of the boom 15bm when the lowering depth of the work machine 13 shown in FIG. 6 is limited. An example of the lowering control of the boom 15bm will be described with reference to the circuit diagram of FIG. 4 and the flowchart of FIG. 8.

First, control the solenoid proportional valve 48bm to fully open, turn on (open) the solenoid switching valve 49bm (step ①), and lower the boom 15bm by the manual operation valve 44bm. It is judged by the signal from the pressure sensor 25bm (step ②), and if the boom lowering operation, the boom 15bm detected by the angle sensors 16bm, 16st, 16bk, such as a resolver. The tip of the bucket blade, whose position is always monitored at the rotation angles of the stick 15st and the bucket 15bk, is the limit of the movable range restricted region in which the movable range of the preset work machine 13 is limited (hereinafter referred to as the end of the restricted zone). It is judged whether or not to approach the () (step ③).

When the tip of the bucket blade approaches the end of the restricted area, the solenoid proportional valve 48bm is slightly closed (step ④) by the control current from the controller 21, thereby lowering the boom from the manual valve 44bm. Through the solenoid proportional valve (48bm) and the solenoid switching valve (49bm) on the side, the pilot pressure supplied to the boom lower side pilot chamber of the main control valve (33bm) is controlled to reduce the pressure, and the spool of the main control valve (33bm) is moved in the neutral position direction. It moves, reduces the flow rate which collides with the rod side of the boom cylinder 14mb from the main control valve 33bm, slows down the shortening operation speed of the boom cylinder 14bm, and slows down the falling speed of the boom 15bm.

This control is repeated until the end of the bucket blade reaches the end of the restricted zone, and gradually reduces the descending speed of the boom 15mb by slowly killing the spool opening angle of the electromagnetic proportional valve 48bm.

In the meantime, it is always judged whether the end of the bucket blade reaches the end of the restricted zone (step ⑤), and when the end of the bucket blade reaches the end of the restricted zone, the solenoid proportional valve 48bm is completely closed (step ⑥), and the main keyword for the boom is By completely removing the pilot pressure acting on the boom lowering pilot chamber of the valve 33bm, the main controller valve 33bm is returned to the neutral position by a spring to stop the lowering of the boom 15bm.

The above is a description of the control method of stopping the boom 15bm at the end of the depth limit zone at the time of spring lowering. However, when the boom 15mb is stopped at the end of the height limit zone at the time of boom up, the stick 15st is moved inward. And when the stick 15st is stopped at the end of the restricted area when rotating outward, the bucket 15bk is stopped at the end of the restricted area when the bucket 15bk is opened and closed. The same control can be performed.

[Industry availability]

As described above, the work machine control device of the construction machine and the control method thereof according to the present invention automatically control the operating range of the work machine even when a work machine such as a hydraulic excavator is manually operated. It is suitable for handling construction machinery such as hydraulic excavators, loaders, backhoes, etc. in narrow places where there is little room in the work space because it is possible to prevent the damage of the counterpart structures.

Claims (4)

A construction machine control device for controlling hydraulic fluid supplied to a hydraulic actuator for operating a work machine by a pilot pressure actuated main control belt, comprising: a manual operation valve for controlling the pilot pressure supplied to the main control valve by manual operation; And a solenoid valve installed in a pilot pressure supply line during manual operation from the manual control valve to the main control valve. A construction machine control device for controlling hydraulic oil supplied to a hydraulic actuator for operating a work machine by a pilot pressure actuated main valve, comprising: a manual operation valve for controlling the pilot pressure supplied to the main control valve by manual operation; And an automatic mode selection valve for selecting a pilot pressure supply line which is separate from the pilot pressure supply line passing through the manual control valve at the time of automatic control of the work machine, and a pilot pressure supplied from one of the manual control valve and the automatic mode selection valve. An electromagnetic proportional valve for controlling the opening angle in accordance with an electric signal, an electromagnetic switching valve for selecting one of the electromagnetic proportional valve and the manual control valve and outputting a pilot pressure to a pilot chamber of the main control valve, the automatic mode selection valve, Controller to control solenoid proportional valve and solenoid switching valve by electric signal And the working machine sensor for detecting the input amount of operation of the work machine to the controller, a work machine control apparatus for a construction machine characterized in that with a manual operation sensors for detecting the input to the manual operation state by the manual operation valves. 3. A work machine control device for a construction machine according to claim 2, wherein a shuttle valve is provided between the manual operation valve and the automatic mode selection valve to output the supply pipe pilot pressure to the electromagnetic proportional valve from one of them. A method of controlling a work machine of a construction machine that controls hydraulic oil supplied to a hydraulic actuator operating a work machine by a pilot pressure actuated main valve, wherein when the work machine approaches its restricted range, it is controlled by manual operation. Construction machinery characterized by reducing the pilot pressure supplied to the main control valve and returning the main control valve to the neutral position by removing the pilot pressure supplied to the main control valve when the working machine reaches its restricted range. How to control the work machine.