JPH0324935B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an excavation control device for a loading shovel.

(Prior art) In a loading shovel, as disclosed in Japanese Patent Publication No. 57-28771, horizontal extrusion is performed while holding the bucket at a constant height by automatically lowering the boom following arm push. ,
Also, when releasing the load scooped into the bucket,
A control device is known that automatically corrects the inclination angle of the bucket with respect to the arm in accordance with the lifting of the boom to prevent the load from spilling.

When performing automatic horizontal extrusion control, the conventional control device described above first switches the switch between manual and automatic horizontal extrusion to manual, moves the bucket, arm, and boom to the target automatic control start position by manual operation, Then, by switching the switch to horizontal extrusion, the starting position of the bucket is fixed as the set value, and by pushing the arm in this state, the boom cylinder will extend and retract according to the set value, following the arm push. In addition, when correcting the bucket tilt angle, the switch between manual and automatic bucket tilt angle correction is switched to manual mode, and the bucket tilt angle correction is manually operated to move the bucket tilt angle to the target automatic control start position. after that,
By switching the above switch to bucket tilt angle correction, the above starting position of the bucket can be fixed as the set value, and by lifting the boom in this state, the bucket cylinder can be extended or contracted based on the above set value to follow the boom raising. It is something to control.

Therefore, two automatic/manual switching switches are required, one for horizontal extrusion and one for bucket tilt angle correction, and the switching operation is troublesome, and it is difficult to automatically perform horizontal extrusion or bucket tilt angle correction. For example, if there is a risk that the bucket cart may hit an obstacle while the bucket cart is running, in order to make the bucket cart avoid the obstacle, the switch must be switched to manual mode and the bucket cart, etc., must be manually operated. This is extremely troublesome and may not be completed in time for emergencies. Note that manual operation is possible with the changeover switch set to automatic, but in this case, manual operation will be added to automatic control, and automatic control and manual operation will be performed at the same time. Even if you operate it, it will not work according to the operator's instructions and is extremely dangerous. Moreover, even if the position of the bucket is changed manually, once automatic control is restarted, control will be resumed based on the initially fixed set value, so there is a risk that the bucket will hit an obstacle again.
In order to avoid this, it is necessary to first change the changeover switch to manual mode, reset the above setting values, and then return the changeover switch to automatic mode again, which causes various problems such as poor operability and workability.

(Purpose of the Invention) The present invention was made to solve these conventional problems, and it is possible to easily select manual/automatic with a single changeover switch, and also allows the changeover switch to be switched even during automatic control. It is possible to operate manually without switching between the two, and it can be operated manually without being interfered with by automatic control.For example, if there is a risk that the bucket may hit an obstacle, it can be quickly avoided, and furthermore, it can be operated manually without being interfered with by automatic control. The purpose of the present invention is to provide a control device that automatically resumes automatic control based on the avoidance point when released, eliminates the need to set the target value again, and improves operability, work efficiency, and safety. It is something.

(Structure of the Invention) The present invention includes a hydraulic cylinder that operates each operating member such as a boom, an arm, and a bucket, a directional control valve that controls the supply and discharge of pressure oil to each hydraulic cylinder, and a spool for each directional control valve. The control valve is equipped with an operating valve to operate, an operating tool corresponding to each operating valve, an operating amount detector for each operating tool, an operating amount detector for each operating object, a changeover switch for selecting automatic/manual, and an arithmetic unit. The arithmetic device selects the automatic control mode when the changeover switch is automatic and only the operating tool of the reference actuator among the actuators is operated, and selects the non-control mode at other times. a circuit, an arithmetic circuit that calculates the position of the bucket door based on the values detected by each of the operating amount detectors in the automatic control mode, and a storage device that stores the position of the bucket door at the start of control in the automatic control mode as a target value;
In the automatic control mode, a control signal corresponding to the operation amount of the operating tool of the reference actuator is output to the operating valve thereof, and a control signal corresponding to the deviation between the target value and the current position of the bucket is output to the reference actuator. and an arithmetic circuit that outputs an output to the operation valve of the actuator that is operated in accordance with It is characterized by the following:

With this configuration, even during automatic control, each actuator can be operated individually in a non-control mode by manual operation as necessary while the selector switch is left in automatic mode.Afterwards, automatic control can be started immediately when the manual operation is released. When the automatic control is resumed, the bucket position at the time of restarting the automatic control is rewritten as a target value, and automatic control can be performed using this new target value as a reference.

(Example) First, the general configuration of the loading shovel is shown in the third example.
This will be explained using figures. In the figure, reference numeral 1 denotes a lower traveling body, and an upper rotating body 2 is rotatably provided on the upper part of the lower traveling body. The base of a boom 3 is supported on the upper revolving body 2 by a pin 9 so as to be able to rise and fall freely, the base of an arm 4 is rotatably attached to the tip of the boom 3 by a pin 10, and the base of a bucket 5 is attached to the tip of the arm 4. It is rotatably attached by a pin 11. The base of the boom cylinder 6 is a pin (not shown)
It is attached to the upper revolving body 2 by a rod, and the tip of the rod is connected to the boom 3 by a pin 12.
The base of the arm cylinder 7 is attached to the boom 3 by a pin (not shown), and the tip of the rod is connected to the arm 4 by a pin 13. The base of the bucket cylinder 8 is attached near the tip of the boom 3, and the rod tip thereof, the tip of a link 16 attached by a pin 15 near the tip of the arm 4, and the link 18 attached to the bucket 5 by a pin 17. are connected to the tip by a pin 19.

In the above loading shovel, boom 3
The length (distance between pins 9 and 10) is l ₁ , and the length of arm 4 (distance between pins 10 and 11) is l ₂
Based on a vertical line C ₁ that is parallel to the rotation center C ₀ of the upper revolving structure 2 and passes through the pin 9, the inclination angle of the boom 3 with respect to the upper revolving structure 2 is θ ₁ , the inclination angle of the arm 4 with respect to the boom 3 is θ ₂ , Let θ ₃ be the inclination angle of bucket 5 with respect to arm 4, θ ₂₀ be the absolute angle of arm 4, and θ be the absolute angle of bucket 5, then θ ₂₀ =θ ₁ +θ ₂ θ=θ ₁ +θ ₂ +θ ₃ . Also, the position or height of the pin 10 at the arm base with respect to the pin 9 at the boom base is h ₁ , the position of the arm tip or the height between pins 10 and 11 is h ₂ , and the pin 11 with respect to pin 9 Let Z be the position, that is, the height, h ₁ = l ₁ cos θ ₁ h ₂ = l ₂ cos (θ ₁ + θ ₂ ) Z = l ₁ cos θ ₁ + l ₂ cos (θ ₁ + θ ₂ ). Here, in order to horizontally move the bucket 5, it is sufficient to control the pin 11 to move horizontally, and furthermore, in order to automatically push out the bucket 5 horizontally simply by pushing the arm, it follows the extension of the arm cylinder 7. It can be seen that the boom cylinder 6 should be retracted and the boom 3 should be controlled so that the height Z becomes constant.

On the other hand, extend the boom cylinder 6 and
When lifting the load that has been scooped into the bucket to the release position, it is necessary to keep the attitude of the bucket 5 constant so that the load does not spill out. 8 and correct the inclination angle θ ₃ of the bucket belt 5 to control the absolute angle θ of the bucket belt 5 to be constant. Therefore, in order to control the loading shovel, the following configuration is used.

FIG. 4 is a hydraulic electrical circuit diagram for operating the loading shovel. In the figure, a main pipe 22 connected to the discharge port of one hydraulic pump 21 is connected to a left travel motor (not shown) via directional control valves 23, 24, 25 for left travel, boom, and bucket. ), the boom cylinder 6 and the bucket cylinder 8 are connected, and the main pipe 32 connected to the discharge port of the other hydraulic pump 31 has a right-hand drive cylinder,
Directional control valves 33, 34, 3 for swing and arm
A right travel motor (not shown), a swing motor (not shown), and an arm cylinder 7 are connected via 5. 26 and 36 are relief valves, and 20 is a tank.

A pilot switching valve is used for each of the directional control valves 24, 35, 25 for the boom, arm, and bucket.
Operation valves 43, 53, and 63 are used to switch. Each operation valve 43, 53, 63 is a pair of electromagnetic proportional pressure reducing valves 44, 45, 54, 5, respectively.
5, 64, and 65, pressure oil is introduced into their primary sides from a hydraulic source 37 such as a pilot pump, and the secondary side is controlled in accordance with control signals (electrical signals) from their controllers 42, 52, and 62. The pilot pressure is introduced into the pilot circuit 4.
6, 47, 56, 57, 66, 67 to the pilot part of each directional control valve 24, 35, 25,
He is trying to switch each direction control valve 24,35,25. 40 is a boom operation lever, 41 is a boom operation amount detector, 50 is an arm operation lever, 51 is an arm operation amount detector, 60 is a bucket operation lever, 61 is a bucket operation amount detector, Each detector 41, 51, 61 is configured with a potentiometer, for example, and each operating lever 40,
50, 60 operation amount (operation direction and operation angle)
It outputs signals M ₁ , M ₂ , M ₃ according to. 70 is a control panel.

FIG. 1 is a block diagram showing the control system of the loading shovel.
The same parts as in FIG. 4 are given the same reference numerals. In FIG. 1, reference numeral 71 denotes an automatic/manual changeover switch, for example, a snap switch, which is attached to the arm operating lever 50. This switch 71 may be provided on a console panel in the driver's cab.

Reference numeral 72 denotes an arithmetic unit, which is composed of, for example, a microcomputer and is incorporated into the control panel 70, and which receives operation signals from each of the operation amount detectors 41, 51, and 61.
Based on the signals from M ₁ , M ₂ , M ₃ and the automatic manual changeover switch 71, arithmetic processing as described later is performed, and control signals are sent to the controllers 42, 52, and 62.
Output E ₁ , E ₂ , E ₃ .

Reference numerals 73, 74, and 75 indicate operation amount detectors, for example angle detectors composed of potentiometers, which are attached to pins 9, 10, and 11, respectively;
The detector 73 detects the inclination angle θ ₁ of the boom 3 with respect to the upper revolving structure 2, and the detector 74 detects the inclination angle θ 1 of the boom 3 with respect to the upper rotating structure 2.
The detector 75 detects the inclination angle _{θ 3 of} the bucket 5 with respect to the arm 4, and outputs signals corresponding to the detected inclination angles θ ₁ , θ ₂ , and θ ₃ .

Next, the operation of the above device will be explained.

First, in Figure 4, for the boom, for the arm,
When each operating lever 40, 50, 60 for the bucket is operated, the operating amount is detected by each operating amount detector 4.
1, 51, and 61, and output operation signals M ₁ , M ₂ , and M ₃ according to the detected values, and
By operating the automatic/manual changeover switch 71, an automatic or manual signal is output. On the other hand, the actuation amount detectors 73, 74, and 75 detect the inclination angle θ ₁ of the boom 3, the inclination angle θ ₂ of the arm 4, and the inclination angle θ ₃ of the bucket belt 5, respectively, and output signals according to the detected values.
Each of the above signals is then sent to the arithmetic unit 72, where the following control is performed.

A control flowchart is shown in FIGS. 2a to 2c.
In the figure, when the program starts, operation signals from each operation amount detector 41, 51, 61 are output.
Each lever 40, 50, 6 based on M ₁ , M ₂ , M ₃
The state of 0 is read (step S ₁ ), and it is determined whether automatic operation is in progress based on the signal from the automatic/manual changeover switch 71 (step S ₂ ).

During automatic operation, it is determined whether or not there is a boom operation (step _S3 ), and if there is no boom operation, it is determined whether or not the arm is pushed (step S3).
_S7 ), when the arm is pushed, the process proceeds to step _S8 and the horizontal push mode is set. In addition, in automatic operation, when there is a boom operation, the process proceeds to step _S4 , where it is determined whether or not to raise the boom, and when raising the boom, it is determined whether or not there is a bucket operation (step S4).
_S5 ), when there is no bucket operation, it is determined whether or not there is an arm operation (step _S9 ), and when there is no arm operation, the process advances to step _S10 and the bucket tilt angle correction mode is set.

In addition, when performing manual movement in step S ₂ above, and when lowering the boom in step S ₄ in automatic operation, step S ₅
When there is a bucket operation at step S9, when there is an arm operation at step _S9 , and when the arm is pulled at step _S7 , the process advances to step _S6 and becomes a non-control mode. In the above control, step _S9 is omitted, and if there is no bucket operation in step _S5 , the step is executed immediately.
It is also possible to proceed to _S10 and set the bucket tilt angle correction mode.

After the control mode is selected as above, the second
Proceeding to the flowchart in Figure b, it is determined whether or not there is a change in the control mode (step _S11 ), and if there is a change, it is determined whether or not it is the horizontal extrusion mode (step _S12 ), and the control mode is changed to the horizontal extrusion mode. time is step
Proceed to S ₁₃ , where the length l ₁ of the boom 3 and the inclination θ ₁ ,
and the target value for the horizontal extrusion mode based on the length l ₂ and the inclination θ ₂ of the arm 4, i.e. the pin 1 at the tip of the arm relative to the pin 9 at the starting point of horizontal extrusion.
1 _is calculated _, and the height _{Z 0 is stored} as a target value _{( step} S _{14 )} .

On the other hand, if NO in step _S12 , it is determined whether or not the bucket tilt angle correction mode is set (step _S15 ).
When in the bucket tilt angle correction mode, the process proceeds to step _S16 , where a target value for bucket tilt angle correction is determined based on the tilt angle θ ₁ of the boom 3, the tilt angle θ ₂ of the arm 4, and the tilt angle θ ₃ of the bucket 5. The absolute angle θ ₀ of the bucket belt 5 at the control start point is calculated, θ ₀ =θ ₁ +θ ₂ +θ ₃ This absolute angle θ ₀ of the bucket belt 5 is stored as a target value (step S ₁₇ ). Note that if NO is selected in step _S11 ,
In either case, or if NO in step _S14 , the process advances to step _S18 , and it is stored that no target value calculation is to be performed.

Next, in FIG. 2c, the boom, arm,
The required control amounts E ₁ , E ₂ , E ₃ corresponding to the respective manipulated variables M ₁ , M ₂ , M ₃ of the bucket are calculated (step S ₁₉ ),
It is determined what the mode is (step _S20 ). Then, in the non-control mode, the above control amounts E ₁ , E ₂ , E ₃
The corresponding control signal is output as is. Also,
In the horizontal extrusion mode, the process proceeds to step _S21 , where the current position Z of the arm tip pin 11 is calculated, and Z=l ₁ cos θ ₁ + l ₂ cos (θ ₁ + θ ₂ ) This current position Z and the above are memorized in step S ₁₃ . The deviation ΔZ from the target position Z ₀ is calculated (step
S ₂₂ ), ΔZ = Z ₀ −Z Based on this deviation ΔZ, the necessary control amount for the boom 3 is calculated in step S ₂₃ , and a control signal corresponding to the arm operation amount M ₂ calculated in step S ₁₉ is calculated. E ₂ is output as is.

On the other hand, in the bucket tilt angle correction mode, the absolute angle θ at the current position of the bucket 5 is calculated (step _S24 ), and θ=θ ₁ +θ ₂ +θ _3This current absolute angle θ and the bucket belt 5 are memorized in step _S17 . The deviation Δθ from the target absolute angle θ ₀ is calculated (step S ₂₅ ), and Δθ = θ ₀ −θ Based on this deviation _Δθ , the bucket is
At the same time, the bucket control amount E ₃ (0 in this case) calculated in step S ₁₉ is rewritten to the control amount calculated in step S ₂₆ , and the bucket control amount E ₃ is calculated. A control signal corresponding to the output is output. In this bucket tilt angle correction mode, the control signal _E1 corresponding to the boom operation amount _M1 calculated in step _S19 is directly output to the boom 3. After each control signal E ₁ , E ₂ , E ₃ is output in this way, the control signal is returned and the above control is repeated.

In the above control, the start of operation of the machine is manually operated. Therefore, initially, the automatic manual changeover switch 71 is set to manual, and each operating lever 4
0, 50, and 60 are operated individually, and therefore the non-control mode (steps S ₁ , S ₂ , S ₆ ) is entered, and the target values, that is, the horizontal extrusion and bucket tilt correction target values, are stored as not being calculated. (steps _S11 , _S18 ), and control signals corresponding to _E1 , _E2 , and _E3 calculated based on the respective operation amounts _M1 , _M2 , and _M3 of the boom, arm, and bucket in step _S19 . is sent as is to the controllers 42, 52, and 62.

The above signals E ₁ , E ₂ , E ₃ are applied to each operating valve 4.
3, 53, and 63, and their electromagnetic proportional pressure reducing valves are activated, and the pilot pressure is also guided to their secondary pipes, and the directional control valves 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 3, 53, 63, for the boom, the arm, and the bucket, respectively, operate the proportional electromagnetic pressure reducing valves. 35 and 25 are switched, each cylinder 6, 7, and 8 is individually extended and contracted, and the boom 3, arm 4, and bucket 5 are individually rotated corresponding to the levers 40, 50, and 60, respectively.

Next, when performing automatic horizontal extrusion of the bucket 5, set the automatic/manual changeover switch 71 to automatic and operate the arm operation lever 50 in the arm pushing direction to switch to the horizontal extrusion mode (step S ₁ ,
S ₂ , S ₃ , S ₇ , S ₈ ), and it is determined in step S ₁₁ that there has been a change, and the target height Z ₀ at the starting point of horizontal extrusion is calculated and the target height Z ₀ is stored once (steps S ₁₂ , S ₁₃ ,
S ₁₄ ), then the operation amount of the arm operation lever 50
A control signal E ₂ corresponding to M ₂ is output, and
A control signal E ₁ corresponding to the deviation ΔZ between the target height Z ₀ and the current position Z is output (steps S ₁₉ , S ₂₀ ,
S ₂₁ , S ₂₂ , S ₂₃ ), each signal E ₁ , E ₂ is sent to the controller 4
Sent to 2,52.

In the arm system, the controller 52
A control signal _E2 is sent to the operating valve 53, and the pilot pressure is guided to the secondary side conduit 57 of the electromagnetic proportional pressure reducing valve 55 for arm pushing, and the arm directional control valve 35
is switched, pressure oil is supplied to the head side of the arm cylinder 7, the cylinder 7 is extended, and the arm 4 is rotated around the pin 11 and pushed forward. At this time, in the boom system, a control signal E ₁ is sent from the controller 42 to the operation valve 43, and the secondary side pipe 4 of the electromagnetic proportional pressure reducing valve 44 for lowering the boom is sent.
6, the directional control valve 24 is switched, pressure oil is supplied to the rod side of the boom cylinder 6, the cylinder 6 is retracted, and the boom 3
is lowered. As a result, the boom 3 following the push of the arm 4 is lowered and controlled in a direction in which the deviation ΔZ becomes 0, the pin 11 is held at a constant height Z ₀ , and the bucket 5 is pushed out horizontally.

On the other hand, when automatically correcting the inclination of the bucket cart 5, that is, when lifting the load scooped into the bucket cart 5 to the discharge position by simply raising the boom, the automatic manual changeover switch 71 is set to automatic, and the boom operation lever 50 is turned to the boom control lever 50. When operated in the upward direction, the bucket tilt angle correction mode (steps S ₁ , S ₂ , S ₃ , S ₄ ,
S ₅ , S ₉ , S ₁₀ ), and it is determined in step S ₁₁ that there has been a change, and the absolute angle θ ₀ of the bucket 5 at the starting point of bucket tilt angle correction is calculated and the absolute angle θ ₀ is temporarily stored as a target value (steps S ₁₂ , S ₁₅ , S ₁₆ , S ₁₇ ), and then
A control signal E ₁ corresponding to the operation amount M ₁ of the boom operation lever 40 is output, and a control signal E ₃ corresponding to the deviation Δθ between the target absolute angle θ ₀ and the current absolute angle θ of the bucket 5 is output ( Steps S ₁₉ , S ₂₀ , S ₂₄ ,
S ₂₅ , S ₂₆ ), the above signals E ₁ and E ₃ are transmitted to the controller 42,
Sent to 62.

Then, in the boom system, the direction control valve 24 is switched by the same action as above based on the signal _E1 , the boom cylinder 6 is extended, and the boom 3 is lowered, and following this, in the bucket system, the above-mentioned A signal _E3 is sent from the controller 62 to the operating valve 63, pilot pressure is guided to the secondary side pipe 67 of the electromagnetic proportional pressure reducing valve 65, the directional control valve 25 is switched, and the bucket cylinder 8 is expanded and contracted to achieve the above-mentioned conditions. The deviation Δθ is controlled to be 0, and the absolute angle θ of the bucket 5 is corrected to be constant. As a result, the bucket cart 5 is raised to the load release position while preventing the load from spilling from the bucket cart 5.

By the way, in the above-mentioned automatic horizontal extrusion of the bucket cart 5, if there is an obstacle such as a rock on the moving path of the bucket cart 5 and the boom is raised, the non-control mode is activated even if the arm is automatically pushed. (steps S ₁ , S ₂ , S ₃ , S ₄ ,
S ₅ , S ₆ ), and the target value is stored as not being calculated (steps S ₁₁ , S ₁₈ ). For this reason, the boom control signal E ₁ calculated according to the boom operation amount M ₁ in step S ₁₉ is sent as is to the controller 42 , and thereafter, the boom-raising proportional electromagnetic pressure reducing valve 4 of the operation valve 43 is transmitted to the controller 42 .
5. Control signals (electrical signals and hydraulic signals) are sequentially sent to the directional control valve 24, the directional control valve 24 is switched, the boom cylinder 6 is extended, and the bucket 5 is prevented from hitting the above-mentioned obstacle.

After that, with the changeover switch 71 set to automatic, release the boom raising operation and perform only the arm push operation to return to the horizontal extrusion mode (steps S ₁ , S ₂ , S ₃ , S ₇ , S ₈ ). And the above bucket 5
The target value Z ₀ is automatically recalculated based on the point at which the robot has avoided the obstacle (steps S ₁₁ , S ₁₂ , S ₁₃ ,
S ₁₄ ), and then automatic horizontal extrusion control is restarted from the above avoidance point (steps S ₁₉ , S ₂₀ , S ₂₁ , S ₂₂ ,
_S23 ). Therefore, there is no need to manually reset the target value as in the prior art.

Also, when correcting the inclination of the bucket 5,
If there is a risk that the bucket 5 will hit an obstacle and, for example, the bucket belt operating lever 60 is operated to rotate the bucket 5 in the pulling direction, the system enters the non-control mode as described above (steps S ₁ , S ₂ ,
S ₃ , S ₄ , S ₅ , S ₆ ), and the target value is stored as not being calculated (steps S ₁₁ , S ₁₈ ), and the bucket control signal is calculated according to the bucket operation amount M ₃ in step S ₂₀ .
E ₃ is sent as is to the controller 62, and the following
Electromagnetic proportional pressure reducing valve 6 for bucket pull of operation valve 63
5. A control signal is sequentially sent to the direction control valve 25 to switch the direction control valve 25, and the bucket cylinder 8
is shortened, and the bucket 5 is prevented from hitting the above-mentioned obstacle.

After that, with the changeover switch 71 set to automatic, release the bucket pull operation and only raise the boom to enter the bucket tilt angle correction mode again (steps S ₁ , S ₂ , S ₃ , S ₄ , S ₅ , S ₉ , S ₁₀ ), and the target value θ ₀ is automatically recalculated based on the point at which the bucket 5 avoids the obstacle (steps S ₁₁ , S ₁₂ , S ₁₅ , S ₁₆ , S ₁₇ ), and thereafter, the bucket tilt angle correction control is restarted from the above-mentioned avoidance point (steps S ₁₉ , S ₂₀ , S ₂₄ , S ₂₅ , S ₂₆ ). Therefore, in this case as well, there is no need to manually reset the target value as in the conventional case.

By the way, in the above embodiment, the arm operation valve 53
As described above, electromagnetic proportional pressure reducing valves 54 and 55 operated by electric signals were used.
A variable pressure reducing valve operated by 0 may also be used.

Further, as an automatic/manual switching means, a switch 7 is used to switch between signals from the operating levers 40, 50, and 60 and signals from the arithmetic unit 72, as shown in FIG.
6, 77, and 78 may be used for hardware switching.

(Effects of the Invention) As described above, the present invention enables the changeover switch to automatically switch to the automatic control mode when only the operating tool of the reference actuator among the above-mentioned actuators is operated, and to de-control at other times. mode, and the position of the bucket at the start of control in automatic control mode is controlled as a target value, and it is possible to easily select between manual and automatic with a single changeover switch, and even when automatic control is in progress. It is also possible to operate the switch manually as needed while leaving the switch set to automatic, and the manual operation can be performed without being interfered with by automatic control. Therefore, for example, if there is a risk that the bucket may hit an obstacle, it can be quickly avoided. Moreover, if you cancel manual operation afterwards, automatic control will automatically resume using that avoidance point as the standard (target value), eliminating the need to set the target value again, improving operability, work efficiency, and safety. It can be done.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a control system showing an embodiment of the present invention, Figs. 2 a to c are flowcharts of the control, Fig. 3 is an overall side view of the loading shovel, and Fig. 4 is its hydraulic and electric power system. Circuit diagram: FIG. 5 is a block diagram of main parts showing another embodiment. 1... Lower traveling body, 2... Upper revolving body, 3...
Boom, 4...Arm, 5...Bucket, 6...
Boom cylinder, 7... Arm cylinder, 8...
Bucket cylinder, 24... Directional control valve for boom, 25... Directional control valve for bucket, 35... Directional control valve for arm, 40, 50, 60... Operation levers for boom, arm, and bucket (operation tool), 41, 51, 61...operation amount detector, 4
2, 52, 62...same controller, 43, 5
3,63... Same operation valve, 71... Automatic manual changeover switch, 72... Arithmetic device, 73, 74, 75...
…Each actuation amount detector for boom, arm, and bucket.

Claims (1)

[Claims] 1 Hydraulic cylinders that operate each actuating member of the boom, arm, and bucket, directional control valves that control the supply and discharge of pressure oil to and from each hydraulic cylinder, operating valves that control the spools of each directional control valve, and each operating valve. an operating tool corresponding to the operating tool, an operating amount detector for each operating tool, an operating amount detector for each of the actuating objects, a changeover switch for selecting automatic manual mode, and an arithmetic device, and the arithmetic device includes A selection circuit that selects the automatic control mode when the changeover switch is automatic and only the operating tool of the reference actuator among the above-mentioned actuators is operated, and selects the non-control mode at other times; An arithmetic circuit that calculates the position of the bucket door based on the detected value by each operating amount detector, a storage device that stores the bucket seat position at the start of control in the automatic control mode as a target value, and a memory device that stores the position of the bucket door at the start of control in the automatic control mode, and an actuator that outputs a control signal corresponding to the operation amount of the operating tool to the operating valve thereof, and operates a control signal corresponding to the deviation between the target value and the current position of the bucket in accordance with the operation of the reference actuator; and an arithmetic circuit that outputs a control signal to each operating valve in a non-control mode, and an arithmetic circuit that outputs a control signal corresponding to the operation amount of each operating tool to each operating valve in a non-control mode. Excavation control device for loading shovel.