JP2022067532A - Work machine - Google Patents

Abstract

To prevent an occurrence of a shock when an intervention control is switched to a manual control.SOLUTION: A control device of a work machine: calculates a primary target speed based on an operation amount of an operation device; and, when a distance between a work tool and a target surface is smaller than a first threshold value, performs an intervention control of calculating a secondary target speed based on a positional relationship between the target surface and the work tool, setting the secondary target speed as a command speed of an actuator, and controlling a speed of the actuator based on the command speed. When a first condition is established in a case where the intervention control is performed and the primary target speed is larger than the secondary target speed, the control device gradually increases the command speed of the actuator from the secondary target speed to the primary target speed. The first condition is established when a variation of a distance is larger than a second threshold value and a distance between the work tool and the target surface is larger than a third threshold value.SELECTED DRAWING: Figure 9

Description

The present invention relates to a working machine.

In Patent Document 1, in a work machine provided with a work device having a work tool such as a bucket, the movement of the work device at the timing of switching between intervention control for the work device and control of the work device based on an operation command from the operation device. A work machine that changes the rate of change in the moving speed of a work device according to the speed is disclosed.

In the work machine described in Patent Document 1, for example, when the intervention control for raising the boom is executed so that the cutting edge of the bucket does not invade the target excavation terrain, the bucket is formed from the area where the target excavation terrain exists. The work equipment controller reduces the boom climb rate over time when it is disengaged and intervention control is no longer needed.

International Publication No. 2016/111384

Some work machines perform intervention control that raises the boom so that the work tool does not enter the target surface when the arm cloud is operated by the operator. In this work machine, when the distance from the target surface to the work tool becomes smaller than a predetermined distance, deceleration control may be performed to reduce the moving speed of the arm.

In this way, when the driven member such as the arm is decelerated by executing the intervention control, the intervention control is not executed from the state where the intervention control is executed because the bucket is removed from the target surface. When the state is changed, the driven member to be decelerated controlled suddenly increases to a speed corresponding to the operation amount of the operator, and a shock may occur.

It is an object of the present invention to prevent the occurrence of a shock due to a rapid increase in the speed of the driven member when the state in which the intervention control is executed is changed to the state in which the intervention control is not executed.

The work machine according to one aspect of the present invention includes a machine body, an articulated work device attached to the machine body and having a plurality of driven members including a work tool and a plurality of actuators for driving the driven member, and the above-mentioned articulated work apparatus. An operating device that operates the work device, a position detection device that detects the position information of the machine, an attitude detection device that detects information about the posture of the work machine, and the target shape data acquired by acquiring the target shape data. The target surface is set based on the position information of the machine and the information on the attitude of the work machine, and when the distance between the work tool and the target surface becomes smaller than the first threshold value, the work tool is set. It is provided with a control device that performs intervention control that intervenes in the operation of the operation device and controls the operation of the work device so as not to excavate the ground beyond the target surface. The control device calculates the primary target speed of the actuator based on the operation amount of the operation device, and when the distance between the work tool and the target surface is smaller than the first threshold value, the control device and the target surface. The intervention that calculates the secondary target speed of the actuator based on the positional relationship of the work tool, sets the secondary target speed as the command speed of the actuator, and controls the speed of the actuator based on the command speed. Control is executed, the distance between the work tool and the target surface and the amount of change thereof are monitored, and the first condition is based on the distance between the work tool and the target surface and the amount of change thereof. When the first condition is satisfied when it is determined whether or not the above is satisfied and the intervention control is executed and the primary target speed is larger than the secondary target speed, the actuator is used. The command speed is gradually increased from the secondary target speed to the primary target speed with the passage of time, and the first condition is that the amount of change in the distance is larger than the second threshold value and the work is performed. It is established when the distance between the tool and the target surface is larger than the third threshold value, and the second threshold value and the third threshold value are values equal to or higher than the first threshold value.

According to the present invention, it is possible to prevent the occurrence of a shock due to a rapid increase in the speed of the driven member when the state in which the intervention control is executed is changed to the state in which the intervention control is not executed.

The perspective view of the hydraulic excavator which concerns on embodiment of this invention. Schematic block diagram of the hydraulic drive system mounted on the hydraulic excavator. Configuration diagram of the hydraulic control unit. Functional block diagram of the controller. The figure which shows the coordinate system (excavator reference coordinate system) in a hydraulic excavator. The figure which shows an example of the locus of the tip part of a bucket when the tip part of a bucket is controlled according to the target velocity vector Vca after correction. The figure which shows the example of the horizontal excavation operation by a machine control. The figure explaining the details of the function of the distance monitoring unit. The flowchart which shows the content of the speed switching control executed by a controller. The figure which shows the target surface distance and the distance change amount when the bucket moves from the upper part of the target surface of a high position to the upper part of the target surface of a low position. The figure which shows the target plane distance and the amount of distance change when a bucket moves from above the area where a target plane exists to above the region where a target plane does not exist. The figure which shows the change of the command speed in the extension direction of an arm cylinder, and the change of the command speed in the extension direction of a boom cylinder when the first condition is satisfied. The figure which shows the change of the command speed in the contraction direction of an arm cylinder, and the change of the command speed in the contraction direction of a boom cylinder when the first condition is satisfied. The figure which shows the target surface distance and the distance change amount when the bucket moves from the upper part of the target surface of a low position to the upper part of the target surface of a high position. The figure which shows the target plane distance and the distance change amount when a bucket moves from above the area where a target plane does not exist, and above the region where a target plane exists. The figure which shows the change of the command speed in the extension direction of an arm cylinder when the 2nd condition is satisfied. The figure which shows the change of the command speed in the contraction direction of an arm cylinder when the 2nd condition is satisfied.

Hereinafter, a hydraulic excavator will be taken as an example of the working machine according to the embodiment of the present invention, and the description will be made with reference to the drawings. In each figure, the same members are designated by the same reference numerals, and duplicated description will be omitted as appropriate.

FIG. 1 is a perspective view of the hydraulic excavator 1 according to the present embodiment. As shown in FIG. 1, the hydraulic excavator (working machine) 1 includes a vehicle body (machine) 1A and an articulated front working device (hereinafter, simply referred to as a working device) 1B attached to the vehicle body 1A. The vehicle body 1A includes a traveling body 11 and a turning body 12 that is rotatably mounted on the traveling body 11. The traveling body 11 is driven by a traveling right motor (not shown) and a traveling left motor 3b. The swivel body 12 is swiveled by a swivel hydraulic motor 4.

The working device 1B has a plurality of driven members (8, 9, 10) rotatably connected and a plurality of actuators (5, 6, 7) for driving the driven members, and is attached to the swivel body 12. Be done. In the present embodiment, the boom 8, the arm 9, and the bucket 10 as the three driven members are connected in series. The boom 8 has its base end rotatably connected by a boom pin 91 (see FIG. 5) at the front of the swivel body 12. The base end of the arm 9 is rotatably connected to the tip of the boom 8 by an arm pin 92 (see FIG. 5). The bucket 10, which is a work tool, is rotatably connected by a bucket pin 93 (see FIG. 5) at the tip of the arm 9. The boom pin 91, arm pin 92, and bucket pin 93 are arranged in parallel with each other, and each driven member (8, 9, 10) can rotate relative to each other in the same plane.

The boom 8 is rotated (driven) by the expansion / contraction operation of the boom cylinder 5. The arm 9 rotates (drives) by the expansion / contraction operation of the arm cylinder 6. The bucket 10 is rotated (driven) by the expansion / contraction operation of the bucket cylinder 7. The boom cylinder 5 is a hydraulic cylinder, one end of which is connected to the boom 8 and the other end of which is connected to the frame of the swivel body 12. The arm cylinder 6 is a hydraulic cylinder, one end of which is connected to the arm 9 and the other end of which is connected to the boom 8. The bucket cylinder 7 is a hydraulic cylinder, one end of which is connected to the bucket 10 via a bucket link (link member) and the other end of which is connected to the arm 9.

A driver's cab 1C on which the operator is boarded is provided on the left side of the front portion of the swivel body 12. In the driver's cab 1C, the traveling right lever 13a and the traveling left lever 13b for giving an operation instruction to the traveling body 11 and the operation right for giving an operation instruction to the boom 8, the arm 9, the bucket 10 and the turning body 12 are provided. A lever 14a and an operation left lever 14b are arranged.

An angle sensor 21 for detecting the rotation angle (boom angle α) of the boom 8 is attached to the boom pin 91 that connects the boom 8 to the swivel body 12. An angle sensor 22 for detecting the rotation angle (arm angle β) of the arm 9 is attached to the arm pin 92 that connects the arm 9 to the boom 8. An angle sensor 23 that detects the rotation angle (bucket angle γ) of the bucket 10 is attached to the bucket pin 93 that connects the bucket 10 to the arm 9. The swivel body 12 has a tilt angle (pitch angle φ) in the front-rear direction and a tilt angle (roll angle ψ) in the left-right direction of the swivel body 12 (vehicle body 1A) with respect to a reference plane (for example, a horizontal plane), and is orthogonal to the swivel center axis. An angle sensor 24 for detecting the relative angle (turning angle θ) of the turning body 12 with respect to the traveling body 11 in the plane is attached. The angle signals output from the angle sensors 21 to 24 are input to the controller 20 (see FIG. 2) described later.

FIG. 2 is a schematic configuration diagram of a hydraulic drive device 100 mounted on the hydraulic excavator 1 shown in FIG. For the sake of simplification of the explanation, FIG. 2 shows only the parts related to the drive of the boom cylinder 5, the arm cylinder 6, the bucket cylinder 7, and the swing hydraulic motor 4, and omits the parts related to the drive of the other hydraulic actuators. ing.

As shown in FIG. 2, the hydraulic drive device 100 includes a hydraulic actuator (4 to 7), a prime mover 49, a hydraulic pump 2 and a pilot pump 48 driven by the prime mover 49, and hydraulic actuators 4 to 7 from the hydraulic pump 2. The flow control valves 16a to 16d for controlling the direction and flow rate of the hydraulic oil (working fluid) supplied to the hydraulic pressure control valves 16a to 16d, the hydraulic pilot type operating devices 15A to 15D for operating the flow control valves 16a to 16d, and the hydraulic control unit. It includes 60, a shuttle block 17, and a controller 20 as a control device for controlling each part of the hydraulic excavator 1.

The prime mover 49 is a power source for the hydraulic excavator 1, and is composed of, for example, an internal combustion engine such as a diesel engine. The hydraulic pump 2 includes a tilting swash plate mechanism (not shown) having a pair of input / output ports, and a regulator 18 that adjusts the tilt angle of the swash plate to adjust the discharge capacity (pushing volume). The regulator 18 is operated by the pilot pressure supplied from the shuttle block 17, which will be described later.

The pilot pump 48 is connected to the pilot pressure control valves 52 to 59 and the hydraulic control unit 60, which will be described later, via the lock valve 51. The lock valve 51 opens and closes according to the operation of a gate lock lever (not shown) provided near the entrance of the driver's cab 1C. When the gate lock lever is operated to the lowered position (unlocking position) that limits the entrance of the driver's cab 1C, the lock valve 51 is opened by a command from the controller 20. As a result, the discharge pressure of the pilot pump 48 (hereinafter referred to as the pilot primary pressure) is supplied to the pilot pressure control valves 52 to 59 and the hydraulic control unit 60, and the flow control valves 16a to 16d can be operated by the operating devices 15A to 15D. Become. On the other hand, when the gate lock lever is operated to the raised position (lock position) for opening the inlet of the driver's cab 1C, the lock valve 51 is closed by a command from the controller 20. As a result, the supply of the pilot primary pressure from the pilot pump 48 to the pilot pressure control valves 52 to 59 and the hydraulic control unit 60 is stopped, and the flow control valves 16a to 16d cannot be operated by the operating devices 15A to 15D.

The operating device 15A is an operating device for operating the boom 8 (boom cylinder 5), and includes a boom operating lever 15a, a boom raising pilot pressure control valve 52, and a boom lowering pilot pressure control valve 53. Here, the boom operating lever 15a corresponds to, for example, an operating right lever 14a (see FIG. 1) when operated in the front-rear direction.

The boom raising pilot pressure control valve 52 reduces the pilot primary pressure supplied via the lock valve 51, and the pilot pressure (hereinafter referred to as the operating amount) corresponding to the lever stroke (hereinafter referred to as the operating amount) of the boom operating lever 15a in the boom raising direction. Hereinafter, the pilot pressure for raising the boom) is generated. The boom raising pilot pressure output from the boom raising pilot pressure control valve 52 is the pilot pressure receiving portion of one of the boom flow rate control valves 16a (left side in the figure) via the hydraulic control unit 60, the shuttle block 17 and the pilot pipe 529. Drives the boom flow control valve 16a to the right in the figure. As a result, the hydraulic oil discharged from the hydraulic pump 2 is supplied to the bottom side of the boom cylinder 5, the hydraulic oil on the rod side is discharged to the tank 50, and the boom cylinder 5 expands.

The boom lowering pilot pressure control valve 53 reduces the pilot primary pressure supplied via the lock valve 51, and the pilot pressure according to the operation amount of the boom operating lever 15a in the boom lowering direction (hereinafter, the boom lowering pilot). Pressure) is generated. The boom lowering pilot pressure output from the boom lowering pilot pressure control valve 53 is the pilot pressure receiving portion of the other side (right side in the figure) of the boom flow rate control valve 16a via the hydraulic control unit 60, the shuttle block 17 and the pilot pipe 539. Drives the boom flow control valve 16a to the left in the figure. As a result, the hydraulic oil discharged from the hydraulic pump 2 is supplied to the rod side of the boom cylinder 5, the hydraulic oil on the bottom side is discharged to the tank 50, and the boom cylinder 5 contracts.

The operating device 15B is an operating device for operating the arm 9 (arm cylinder 6), and includes an arm operating lever 15b, an arm cloud pilot pressure control valve 54, and an arm dump pilot pressure control valve 55. Here, the arm operation lever 15b corresponds to, for example, the operation left lever 14b (see FIG. 1) when operated in the left-right direction.

The pilot pressure control valve 54 for the arm cloud reduces the pilot primary pressure supplied via the lock valve 51, and the pilot pressure according to the operation amount of the operation lever 15b for the arm in the arm cloud direction (hereinafter referred to as the pilot for the arm cloud). Pressure) is generated. The pilot pressure for the arm cloud output from the pilot pressure control valve 54 for the arm cloud is the pilot pressure receiving portion of one of the flow control valves 16b for the arm (left side in the figure) via the hydraulic control unit 60, the shuttle block 17 and the pilot pipe 549. The flow control valve 16b for the arm is driven to the right in the drawing. As a result, the hydraulic oil discharged from the hydraulic pump 2 is supplied to the bottom side of the arm cylinder 6, the hydraulic oil on the rod side is discharged to the tank 50, and the arm cylinder 6 is extended.

The pilot pressure control valve 55 for arm dump reduces the pilot primary pressure supplied via the lock valve 51, and the pilot pressure according to the operation amount of the arm operation lever 15b in the arm dump direction (hereinafter referred to as arm dump pilot). Pressure) is generated. The arm dump pilot pressure output from the arm dump pilot pressure control valve 55 is the pilot pressure receiving portion of the other side (right side in the figure) of the arm flow control valve 16b via the hydraulic control unit 60, the shuttle block 17, and the pilot pipe 559. The flow control valve 16b for the arm is driven to the left in the figure. As a result, the hydraulic oil discharged from the hydraulic pump 2 is supplied to the rod side of the arm cylinder 6, the hydraulic oil on the bottom side is discharged to the tank 50, and the arm cylinder 6 contracts.

The operating device 15C is an operating device for operating the bucket 10 (bucket cylinder 7), and includes a bucket operating lever 15c, a bucket cloud pilot pressure control valve 56, and a bucket dump pilot pressure control valve 57. Here, the bucket operation lever 15c corresponds to, for example, the operation right lever 14a (see FIG. 1) when operated in the left-right direction.

The pilot pressure control valve 56 for the bucket cloud reduces the pilot primary pressure supplied via the lock valve 51, and the pilot pressure according to the operation amount of the bucket operating lever 15c in the bucket cloud direction (hereinafter, the pilot for the bucket cloud). Pressure) is generated. The pilot pressure for the bucket cloud output from the pilot pressure control valve 56 for the bucket cloud is the pilot pressure receiving portion of one of the flow control valves 16c for the bucket (left side in the figure) via the hydraulic control unit 60, the shuttle block 17 and the pilot pipe 569. The flow control valve 16c for the bucket is driven to the right in the figure. As a result, the hydraulic oil discharged from the hydraulic pump 2 is supplied to the bottom side of the bucket cylinder 7, the hydraulic oil on the rod side is discharged to the tank 50, and the bucket cylinder 7 is extended.

The bucket dump pilot pressure control valve 57 reduces the pilot primary pressure supplied via the lock valve 51, and the pilot pressure according to the operation amount of the bucket operating lever 15c in the bucket dump direction (hereinafter, bucket dump pilot). Pressure) is generated. The bucket dump pilot pressure output from the bucket dump pilot pressure control valve 57 is the pilot pressure receiving portion of the other side (right side in the figure) of the bucket flow control valve 16c via the hydraulic control unit 60, the shuttle block 17, and the pilot pipe 579. The flow control valve 16c for the bucket is driven to the left in the figure. As a result, the hydraulic oil discharged from the hydraulic pump 2 is supplied to the rod side of the bucket cylinder 7, the hydraulic oil on the bottom side is discharged to the tank 50, and the bucket cylinder 7 contracts.

The operating device 15D includes a turning operation lever 15d, a right turning pilot pressure control valve 58, and a left turning pilot pressure control valve 59. Here, the turning operation lever 15d corresponds to, for example, the operation left lever 14b (see FIG. 1) when operated in the front-rear direction.

The right-turning pilot pressure control valve 58 reduces the pilot primary pressure supplied via the lock valve 51, and the pilot pressure according to the amount of operation of the turning operation lever 15d in the right-handed turning direction (hereinafter, right-handed turning). Generates a diversion pilot pressure). The right turning pilot pressure output from the right turning pilot pressure control valve 58 is guided to the pilot pressure receiving portion of one of the turning flow rate control valves 16d (on the right side in the figure) via the shuttle block 17 and the pilot pipe 589. , The flow rate control valve 16d for turning is driven to the left in the figure. As a result, the hydraulic oil discharged from the hydraulic pump 2 flows into the inlet / outlet port of one (right side in the figure) of the swing hydraulic motor 4, and the hydraulic oil flowing out from the inlet / outlet port of the other (left side in the figure) is discharged to the tank 50. The swivel hydraulic motor 4 rotates in one direction (the direction in which the swivel body 12 is swiveled to the right).

The left turning pilot pressure control valve 59 reduces the pilot primary pressure supplied via the lock valve 51, and the pilot pressure according to the amount of operation of the turning operation lever 15d in the left turning direction (hereinafter, left turning pilot). Pressure) is generated. The left turning pilot pressure output from the left turning pilot pressure control valve 59 is guided to the pilot pressure receiving portion on the other side (left side in the figure) of the turning flow rate control valve 16d via the shuttle block 17 and the pilot pipe 599, and turns. The flow rate control valve 16d is driven to the right in the figure. As a result, the hydraulic oil discharged from the hydraulic pump 2 flows into the inlet / outlet port of the other side (left side in the figure) of the swing hydraulic motor 4, and the hydraulic oil flowing out from the inlet / outlet port of one side (right side in the figure) is discharged to the tank 50. The swivel hydraulic motor 4 rotates in the other direction (the direction in which the swivel body 12 is swiveled to the left).

The hydraulic control unit 60 is a device for executing machine control (MC), corrects the pilot pressure input from the pilot pressure control valves 52 to 57 in response to a command from the controller 20, and outputs the pilot pressure to the shuttle block 17. do. This makes it possible for the working device 1B to perform a desired operation regardless of the lever operation of the operator.

The shuttle block 17 outputs the pilot pressure input from the hydraulic control unit 60 to the pilot pipes 529, 539, 549, 559, 569, 579. Further, the shuttle block 17 selects the maximum pilot pressure among the input pilot pressures and outputs the maximum pilot pressure to the regulator 18 of the hydraulic pump 2. This makes it possible to control the discharge flow rate of the hydraulic pump 2 according to the operation amount of the operation levers 15a to 15d.

FIG. 3 is a block diagram of the hydraulic control unit 60 shown in FIG. As shown in FIG. 3, the hydraulic control unit 60 includes an electromagnetic isolation valve 61, a shuttle valve 522,534,564,574, and an electromagnetic proportional valve 525,532,537,542,552,562,567,572,557. And have.

The inlet port of the electromagnetic isolation valve 61 is connected to the outlet port of the lock valve 51 (see FIG. 2). The outlet port of the electromagnetic isolation valve 61 is connected to the inlet port of the electromagnetic proportional valves 525,537,567,577. The opening degree of the electromagnetic isolation valve 61 is set to zero when the power is off, and the opening degree is maximized by supplying a current from the controller 20. When the machine control is enabled, the opening degree of the electromagnetic isolation valve 61 is maximized, and the supply of the pilot primary pressure to the electromagnetic proportional valves 525, 537, 567, 577 is started. On the other hand, when the machine control is disabled, the opening degree of the electromagnetic isolation valve 61 is set to zero, and the supply of the pilot primary pressure to the electromagnetic proportional valves 525, 537, 567, 577 is stopped.

Switching between valid and invalid machine control is performed based on an operation signal from the MC switch 26 (see FIG. 2) provided in the driver's cab 1C. The MC switch 26 is, for example, an alternate operation type switch provided on the operation right lever 14a or the operation left lever 14b. When the operation signal for enabling machine control is input from the MC switch 26, the controller 20 supplies a control current to the solenoid of the electromagnetic isolation valve 61 to maximize the opening degree of the electromagnetic isolation valve 61. When the operation signal for disabling the machine control is input from the MC switch 26, the controller 20 stops the supply of the control current to the solenoid of the electromagnetic isolation valve 61 and makes the opening degree of the electromagnetic isolation valve 61 zero.

The shuttle valve 522 has two inlet ports and one outlet port, and outputs the high pressure side of the pressure input from the two inlet ports from the outlet port. One inlet port of the shuttle valve 522 is connected to the boom raising pilot pressure control valve 52 via the pilot pipe 521. The other inlet port of the shuttle valve 522 is connected to the outlet port of the electromagnetic proportional valve 525 via a pilot pipe 524. The outlet port of the shuttle valve 522 is connected to the shuttle block 17 via the pilot pipe 523.

The inlet port of the electromagnetic proportional valve 525 is connected to the outlet port of the electromagnetic isolation valve 61. The outlet port of the electromagnetic proportional valve 525 is connected to the other inlet port of the shuttle valve 522 via a pilot pipe 524. The opening degree of the electromagnetic proportional valve 525 is set to zero when the power is off, and the opening degree is increased according to the current supplied from the controller 20. The electromagnetic proportional valve 525 reduces the pilot primary pressure supplied via the electromagnetic isolation valve 61 according to its opening degree, and outputs the pressure to the pilot pipe 524. As a result, even when the boom raising pilot pressure is not supplied from the boom raising pilot pressure control valve 52 to the pilot pipe 521, the boom raising pilot pressure can be supplied to the pilot pipe 523. When the machine control for the boom raising operation is not executed, the electromagnetic proportional valve 525 is in a non-energized state, and the opening degree of the electromagnetic proportional valve 525 becomes zero. At this time, since the boom raising pilot pressure supplied from the boom raising pilot pressure control valve 52 is guided to one of the pilot pressure receiving portions of the boom flow rate control valve 16a, the boom raising operation can be performed according to the lever operation of the operator. Will be.

The shuttle valve 534 has two inlet ports and one outlet port, and outputs the high pressure side of the pressure input from the two inlet ports from the outlet port. One inlet port of the shuttle valve 534 is connected to the outlet port of the electromagnetic proportional valve 532 via a pilot pipe 533. The other inlet port of the shuttle valve 534 is connected to the outlet port of the electromagnetic proportional valve 537 via a pilot pipe 536. The outlet port of the shuttle valve 534 is connected to the shuttle block 17 via the pilot pipe 535.

The inlet port of the electromagnetic proportional valve 532 is connected to the boom lowering pilot pressure control valve 53 via the pilot pipe 531. The outlet port of the electromagnetic proportional valve 532 is connected to one inlet port of the shuttle valve 534 via the pilot pipe 533. The electromagnetic proportional valve 532 has a maximum opening when not energized, and the opening is reduced from the maximum to zero according to the current supplied from the controller 20. The electromagnetic proportional valve 532 reduces the boom lowering pilot pressure input via the pilot pipe 531 according to the opening degree, and outputs the pressure to the pilot pipe 533. This makes it possible to reduce or reduce the boom lowering pilot pressure by operating the lever of the operator to zero.

The inlet port of the electromagnetic proportional valve 537 is connected to the outlet port of the electromagnetic isolation valve 61, and the outlet port of the electromagnetic proportional valve 537 is connected to the other inlet port of the shuttle valve 534 via the pilot pipe 536. .. The opening degree of the electromagnetic proportional valve 537 is set to zero when the power is off, and the opening degree is increased according to the current supplied from the controller 20. The electromagnetic proportional valve 537 reduces the pilot primary pressure supplied via the electromagnetic isolation valve 61 according to its opening degree, and outputs the pressure to the pilot pipe 536. This makes it possible to supply the boom lowering pilot pressure to the pilot pipe 535 even when the boom lowering pilot pressure is not supplied from the boom lowering pilot pressure control valve 53 to the pilot pipe 531. When the machine control for the boom lowering operation is not executed, the electromagnetic proportional valve 532 and 537 are in a non-energized state, the opening degree of the electromagnetic proportional valve 532 is fully opened, and the opening degree of the electromagnetic proportional valve 537 is zero. At this time, since the boom lowering pilot pressure supplied from the boom lowering pilot pressure control valve 53 is guided to the other pilot pressure receiving portion of the boom flow rate control valve 16a, the boom lowering operation can be performed according to the lever operation of the operator. Will be.

The inlet port of the electromagnetic proportional valve 542 is connected to the pilot pressure control valve 54 for the arm cloud via the pilot pipe 541. The outlet port of the electromagnetic proportional valve 542 is connected to the shuttle block 17 via the pilot pipe 543. The electromagnetic proportional valve 542 maximizes the opening degree when not energized, and reduces the opening degree from the maximum to zero according to the current supplied from the controller 20. The electromagnetic proportional valve 542 reduces the arm cloud pilot pressure input via the pilot pipe 541 according to the opening degree, and outputs the pressure to the pilot pipe 543. This makes it possible to reduce or reduce the arm cloud pilot pressure by operating the operator's lever. When the machine control for the arm cloud operation is not executed, the electromagnetic proportional valve 542 is in a non-energized state, and the opening degree of the electromagnetic proportional valve 542 is fully opened. At this time, since the pilot pressure for the arm cloud supplied from the pilot pressure control valve 54 for the arm cloud is guided to one of the pilot pressure receiving portions of the flow control valve 16b for the arm, the arm cloud operation according to the lever operation of the operator is possible. Will be.

The inlet port of the electromagnetic proportional valve 552 is connected to the pilot pressure control valve 55 for arm dump via the pilot pipe 551. The outlet port of the electromagnetic proportional valve 552 is connected to the shuttle block 17 via the pilot pipe 553. The electromagnetic proportional valve 552 maximizes the opening degree when not energized, and reduces the opening degree from the maximum to zero according to the current supplied from the controller 20. The electromagnetic proportional valve 552 reduces the arm dump pilot pressure input via the pilot pipe 551 according to the opening degree, and outputs the pressure to the pilot pipe 553. This makes it possible to reduce or reduce the arm dump pilot pressure by operating the lever of the operator to zero. When the machine control for the arm dump operation is not executed, the electromagnetic proportional valve 552 is in a non-energized state, and the opening degree of the electromagnetic proportional valve 552 is fully opened. At this time, since the arm dump pilot pressure supplied from the arm dump pilot pressure control valve 55 is guided to the other pilot pressure receiving portion of the arm flow control valve 16b, the arm dump operation can be performed according to the lever operation of the operator. Will be.

The shuttle valve 564 has two inlet ports and one outlet port, and outputs the high pressure side of the pressure input from the two inlet ports from the outlet port. One inlet port of the shuttle valve 564 is connected to the outlet port of the electromagnetic proportional valve 562 via a pilot pipe 563. The other inlet port of the shuttle valve 564 is connected to the outlet port of the electromagnetic proportional valve 567 via a pilot pipe 566. The outlet port of the shuttle valve 564 is connected to the shuttle block 17 via the pilot pipe 565.

The inlet port of the electromagnetic proportional valve 562 is connected to the bucket cloud pilot pressure control valve 56 via the pilot pipe 561. The outlet port of the electromagnetic proportional valve 562 is connected to one inlet port of the shuttle valve 564 via the pilot pipe 563. The electromagnetic proportional valve 562 maximizes the opening degree when not energized, and reduces the opening degree from the maximum to zero according to the current supplied from the controller 20. The electromagnetic proportional valve 562 reduces the bucket cloud pilot pressure input via the pilot pipe 561 according to the opening degree, and outputs the pressure to the pilot pipe 563. This makes it possible to reduce or reduce the pilot pressure for the bucket cloud by operating the lever of the operator.

The inlet port of the electromagnetic proportional valve 567 is connected to the outlet port of the electromagnetic isolation valve 61, and the outlet port of the electromagnetic proportional valve 567 is connected to the other inlet port of the shuttle valve 564 via the pilot pipe 566. .. The opening degree of the electromagnetic proportional valve 567 is set to zero when the power is off, and the opening degree is increased according to the current supplied from the controller 20. The electromagnetic proportional valve 567 reduces the pilot primary pressure supplied via the electromagnetic isolation valve 61 according to its opening degree, and outputs the pressure to the pilot pipe 566. As a result, even when the bucket cloud pilot pressure is not supplied from the bucket cloud pilot pressure control valve 56 to the pilot pipe 561, the bucket cloud pilot pressure can be supplied to the pilot pipe 565. When the machine control for the bucket cloud operation is not executed, the electromagnetic proportional valve 562 and 567 are in a non-energized state, the opening degree of the electromagnetic proportional valve 562 is fully opened, and the opening degree of the electromagnetic proportional valve 567 is zero. At this time, since the pilot pressure for the bucket cloud supplied from the pilot pressure control valve 56 for the bucket cloud is guided to one of the pilot pressure receiving portions of the flow control valve 16c for the bucket, the bucket cloud operation according to the lever operation of the operator is possible. Will be.

The shuttle valve 574 has two inlet ports and one outlet port, and outputs the high pressure side of the pressure input from the two inlet ports from the outlet port. One inlet port of the shuttle valve 574 is connected to the outlet port of the electromagnetic proportional valve 572 via a pilot pipe 573. The other inlet port of the shuttle valve 574 is connected to the outlet port of the electromagnetic proportional valve 577 via a pilot pipe 576. The outlet port of the shuttle valve 574 is connected to the shuttle block 17 via a pilot pipe 575.

The inlet port of the electromagnetic proportional valve 572 is connected to the bucket dump pilot pressure control valve 57 via the pilot pipe 571. The outlet port of the electromagnetic proportional valve 572 is connected to one inlet port of the shuttle valve 574 via the pilot pipe 573. The electromagnetic proportional valve 572 maximizes the opening degree when not energized, and reduces the opening degree from the maximum to zero according to the current supplied from the controller 20. The electromagnetic proportional valve 572 reduces the bucket dump pilot pressure input via the pilot pipe 571 according to its opening degree and supplies it to the pilot pipe 573. This makes it possible to reduce or reduce the bucket dump pilot pressure by operating the lever of the operator to zero.

The inlet port of the electromagnetic proportional valve 577 is connected to the outlet port of the electromagnetic isolation valve 61. The outlet port of the electromagnetic proportional valve 577 is connected to the other inlet port of the shuttle valve 574 via a pilot pipe 576. The electromagnetic proportional valve 577 has an opening degree of zero when not energized, and increases the opening degree according to the current supplied from the controller 20. The electromagnetic proportional valve 577 reduces the pilot primary pressure supplied via the electromagnetic isolation valve 61 according to its opening degree and supplies it to the pilot pipe 576. As a result, even when the bucket dump pilot pressure is not supplied from the bucket dump pilot pressure control valve 57 to the pilot pipe 571, the bucket dump pilot pressure can be supplied to the pilot pipe 575. When the machine control for the bucket dump operation is not executed, the electromagnetic proportional valve 572, 577 is in a non-energized state, the opening degree of the electromagnetic proportional valve 572 is fully opened, and the opening degree of the electromagnetic proportional valve 577 is zero. At this time, since the bucket dump pilot pressure supplied from the bucket dump pilot pressure control valve 57 is guided to the other pilot pressure receiving portion of the bucket flow control valve 16c, the bucket dump operation can be performed according to the operator's lever operation. Will be.

The pilot pipe 521 is provided with a pressure sensor 526 that detects the boom raising pilot pressure supplied from the boom raising pilot pressure control valve 52. The pilot pipe 531 is provided with a pressure sensor 538 that detects the boom lowering pilot pressure supplied from the boom lowering pilot pressure control valve 53. The pilot pipe 541 is provided with a pressure sensor 544 that detects the arm cloud pilot pressure supplied from the arm cloud pilot pressure control valve 54. The pilot pipe 551 is provided with a pressure sensor 554 that detects the arm dump pilot pressure supplied from the arm dump pilot pressure control valve 55. The pilot pipe 561 is provided with a pressure sensor 568 that detects the bucket cloud pilot pressure supplied from the bucket cloud pilot pressure control valve 56. The pilot pipe 571 is provided with a pressure sensor 578 that detects the bucket dump pilot pressure supplied from the bucket dump pilot pressure control valve 57. The pilot pressure detected by the pressure sensors 526,538,544,554,568,578 is input to the controller 20 as an operation signal indicating the operation direction and the operation amount of the operation devices 15A to 15C for operating the work device 1B.

As shown in FIG. 2, the controller 20 includes a CPU (Central Processing Unit) 20a as an operating circuit, a ROM (Read Only Memory) 20b as a storage device, a RAM (Random Access Memory) 20c as a storage device, and an input interface 20d. It is composed of a microcomputer equipped with an output interface 20e and other peripheral circuits. The controller 20 may be configured by one microcomputer or may be configured by a plurality of microcomputers.

The ROM 20b is a non-volatile memory such as an EEPROM, and stores a program capable of executing various operations. That is, the ROM 20b is a storage medium capable of reading a program that realizes the functions of the present embodiment. The RAM 20c is a volatile memory, and is a work memory that directly inputs and outputs data to and from the CPU 20a. The RAM 20c temporarily stores necessary data while the CPU 20a calculates and executes the program. The controller 20 may further include a storage device such as a flash memory or a hard disk drive.

The CPU 20 is a processing device that expands the program stored in the ROM 20b into the RAM 20c and executes the calculation, and performs predetermined calculation processing on the signals taken from the input interface 20d and the ROM 20b and the RAM 20c according to the program. Signals from the MC switch 26, the attitude detection device 35, the target surface setting device 36, the operation detection device 34, the position detection device 47, and the like are input to the input interface 20d.

The input interface 20d converts the input signal so that the CPU 20a can calculate it. Further, the output interface 20e generates a signal for output according to the calculation result of the CPU 20a, and uses the signal as an electromagnetic proportional valve 525,532,537,542,552,562,567,572,577, and an electromagnetic isolation valve. Output to a valve 61 (see FIG. 3) or the like.

The attitude detection device 35 has angle sensors 21 to 24 (see FIG. 1). These angle sensors 21 to 24 detect information about the posture of the hydraulic excavator 1 and output a signal corresponding to the information. That is, the angle sensors 21 to 24 function as posture sensors that detect information regarding the posture of the hydraulic excavator 1.

For the angle sensors 21, 22, and 23, a potentiometer that acquires a boom angle α, an arm angle β, and a bucket angle γ as information on the posture of the work device 1B and outputs a signal (voltage) according to the acquired angles is adopted. be able to.

The angle sensor 24 acquires angular speeds and accelerations of three orthogonal axes as information on the posture of the swivel body 12, and based on this information, the roll angle of the swivel body 12 (tilt angle in the left-right direction of the swivel body 12) ψ, IMU (Inertial Measurement Unit) that calculates the pitch angle (tilt angle of the swivel body 12 in the front-rear direction) φ and the swivel angle θ and outputs the calculation result (information about the angles ψ, φ, θ) to the controller 20. Can be adopted. The calculation of the angles ψ, φ, and θ representing the posture of the swivel body 12 may be performed by the controller 20 based on the output signal of the IMU. Further, as the angle sensor 24, three sensors, that is, a sensor for detecting the roll angle ψ, a sensor for detecting the pitch angle φ, and a sensor for detecting the turning angle θ may be provided.

The operation detection device 34 has a pressure sensor 526,538,544,554,568,578 (see FIG. 3).

The position detecting device 47 is used to detect the current position information of the swivel body 12 of the hydraulic excavator 1. As shown in FIG. 4, the position detection device 47 includes antennas (hereinafter referred to as GNSS antennas) 47a and 47b for a plurality of GNSS (Global Navigation Satellite Systems) and GNSS antennas 47a and 47b. It has a positioning calculation device 47c that calculates the position and orientation of the swivel body 12 in the geographic coordinate system (global coordinate system) based on satellite signals (GNSS radio waves) from a plurality of received positioning satellites. The GNSS antennas 47a and 47b are provided at positions separated from each other in the left-right direction of the swivel body 12 in the upper part of the swivel body 12.

The GNSS antenna 47a receives reference position data used for calculating its own position from the positioning satellite. The GNSS antenna 47b receives reference position data used for calculating its own position from the positioning satellite. The GNSS antennas 47a and 47b receive reference position data at, for example, a 10 Hz cycle. Each time the GNSS antennas 47a and 47b receive the reference position data, they output the reference position data to the positioning calculation device 47c.

The positioning arithmetic unit 47c calculates the reference position P1 of the GNSS antenna 47a and the reference position P2 of the GNSS antenna 47b represented by the global coordinate system based on the signals (reference position data) received by the GNSS antennas 47a and 47b. .. The positioning calculation device 47c calculates a baseline vector connecting the reference position P1 and the reference position P2. The positioning calculation device 47c calculates the position of the swivel body 12 and the orientation of the swivel body 12 based on the reference positions P1 and P2 and the baseline vector. The orientation of the swivel body 12 is represented, for example, by an angle of global coordinates with respect to a reference orientation (eg, north). The positioning arithmetic unit 47c calculates the position and orientation of the swivel body 12 each time it acquires two reference position data from the GNSS antennas 47a and 47b at a frequency of, for example, 10 Hz, and outputs the data to the controller 20.

The position of the swivel body 12 is an arbitrary position of the swivel body 12, and is set to, for example, a position on the swivel center axis, a position on the center axis of the boom pin 91, and the like. In the storage device (for example, ROM) of the positioning calculation device 47c, geometric information representing the relationship between the coordinates of the positions of the GNSS antennas 47a and 47b in the vehicle body coordinate system and the coordinates of the position of the swivel body 12 arbitrarily set is shown. (Dimension data, etc.) is stored. Therefore, the positioning calculation device 47c can calculate the coordinates and orientation of the position of the swivel body 12 in the geographic coordinate system based on the two reference positions P1 and P2, the baseline vector, and the geometric information.

When the predetermined condition is satisfied, the controller 20 shown in FIG. 2 executes machine control for controlling the work apparatus 1B based on the target surface St. In machine control, the controller 20 outputs a control signal for driving the corresponding flow rate control valves 16a, 16b, 16c to the hydraulic control unit 60. For example, the controller 20 extends the boom cylinder 5 by outputting a control signal for operating the flow rate control valve 16a to the electromagnetic proportional valve 525 (see FIG. 3) to forcibly perform the boom raising operation. The machine control is, for example, an area limitation control (ground leveling control) executed when the arm operation is performed by the operating device 15B, and a boom lowering operation executed when the boom lowering operation is performed by the operating device 15A without the arm operation. Includes stop control and.

As shown in FIG. 7, the controller 20 controls at least one of the hydraulic actuators (5, 6, 7) so that the tip end portion (for example, a toe) of the bucket 10 is located on or above the predetermined target surface St. do. In the area limitation control, the operation of the work apparatus 1B is controlled so that the tip end portion of the bucket 10 moves along the target surface St by the arm operation. Specifically, the controller 20 issues a boom up or boom down command so that the velocity vector at the tip of the bucket 10 in the direction perpendicular to the target surface St becomes zero when the arm is operated. In the area limitation control, the distance (target surface distance) between the tip of the bucket 10 and the target surface St is a predetermined distance Ya1 (Fig.) With the machine control enabled by the MC switch 26. It is performed when it becomes smaller than 6).

In the present embodiment, the control point of the work device 1B used in the machine control is set to the toe of the bucket 10 of the hydraulic excavator 1, but if the control point is the point of the tip portion of the work device 1B, the bucket. It is possible to change other than the 10 toes. For example, the bottom surface of the bucket 10 or the outermost side of the bucket link may be set as a control point. A configuration may be adopted in which a point on the outer surface of the bucket 10 closest to the target surface St is appropriately set as a control point.

FIG. 4 is a functional block diagram of the controller 20 shown in FIG.

As shown in FIG. 4, the controller 20 executes a program stored in the ROM 20b to execute a posture calculation unit 30, a target surface setting unit 37, a target operation calculation unit 32, a solenoid valve control unit 33, and a distance monitoring unit. It functions as 40 and a command value switching unit 39. The electromagnetic proportional valve 500 shown in FIG. 4 is representative of the electromagnetic proportional valve 525,532,537,542,552,562,567,572,577 (see FIG. 3).

The posture calculation unit 30 calculates the posture of the hydraulic excavator 1 (posture of the work device 1B and the swivel body 12) based on the posture information from the posture detection device 35 and the position information from the position detection device 47. The posture calculation unit 30 is based on the posture information from the posture detection device 35 and the geometric information of the work device 1B stored in the ROM 20b (for example, the lengths L1, L2, L3 of the driven member shown in FIG. 5). The position (hereinafter, also referred to as the tip position) Pb of the tip portion (for example, the tip of the bucket 10) of the bucket 10 in the local coordinate system (excavator reference coordinate system) is calculated.

The posture of the working device 1B can be defined based on the excavator reference coordinate system of FIG. FIG. 5 is a diagram showing a coordinate system (excavator reference coordinate system) in the hydraulic excavator 1. The excavator reference coordinate system of FIG. 5 is a coordinate system set for the swivel body 12. In the excavator reference coordinate system, the central axis of the boom pin 91 is set as the origin O, the axis parallel to the turning central axis of the swivel body 12 is set as the Y axis, and the Y axis and the axis orthogonal to the boom pin 91 are set as the X axis. .. The tilt angle of the boom 8 with respect to the X axis is defined as the boom angle α, the tilt angle of the arm 9 with respect to the boom 8 is defined as the arm angle β, and the tilt angle of the bucket 10 with respect to the arm 9 is defined as the bucket angle γ. The tilt angle of the vehicle body 1A (swivel body 12) with respect to the horizontal plane (reference plane) in the front-rear direction, that is, the angle formed by the horizontal plane (reference plane) and the X-axis is defined as the pitch angle φ.

The boom angle α is detected by the angle sensor 21, the arm angle β is detected by the angle sensor 22, the bucket angle γ is detected by the angle sensor 23, and the pitch angle φ is detected by the angle sensor 24.

The length from the center position of the boom pin 91 to the center position of the arm pin 92 is L1, the length from the center position of the arm pin 92 to the center position of the bucket pin 93 is L2, and the length from the center position of the bucket pin 93 to the tip of the bucket 10 ( Assuming that the length to the tip of the toe is L3, the tip position Pb of the bucket 10 in the excavator reference coordinates can be expressed by the following equations (1) and (2) with Xbk as the X-direction position and Ybk as the Y-direction position. can.

The posture calculation unit 30 shown in FIG. 4 includes the tip position Pb of the bucket 10 in the excavator reference coordinate system, the pitch angle φ of the swivel body 12, the position of the hydraulic excavator 1 in the global coordinate system calculated by the positioning calculation device 47c, and the position of the hydraulic excavator 1. The tip position Pb of the bucket 10 in the global coordinate system is calculated based on the orientation. That is, the posture calculation unit 30 converts the tip position Pb in the shovel reference coordinate system into the tip position Pb in the global coordinate system.

In addition to the tip position Pb of the bucket 10, the posture calculation unit 30 also calculates the boom pin 91, the arm pin 92 and the bucket pin 93, the position of the origin O in the global coordinate system, etc., which represents the posture of the work device 1B, and calculates these. The posture information of the hydraulic excavator 1 is output to the target surface setting unit 37, the target motion calculation unit 32, and the distance monitoring unit 40. In addition to the calculation result, the attitude calculation unit 30 uses the angle information (α, β, γ, θ, φ, ψ) detected by the attitude detection device 35 as the attitude information, and the target surface setting unit 37 and the target motion calculation. Output to unit 32.

The target surface setting device 36 is a device for inputting target shape data used for setting the target surface St used in machine control to the controller 20. The target surface setting device 36 includes a storage device that stores three-dimensional target shape data defined on the global coordinate system (absolute coordinate system). The target surface setting unit 37 acquires three-dimensional target shape data from the target surface setting device 36, and obtains the acquired target shape data and attitude information from the attitude calculation unit 30 (the attitude of the hydraulic excavator 1 in the global coordinate system). The target surface St is set based on the information to be represented). The target surface setting unit 37 sets the cross-sectional shape obtained by cutting the target shape data on the plane on which the work device 1B moves (the operation plane (XY plane) of the work device 1B) as the two-dimensional target surface. The operating plane of the working device 1B can be calculated based on, for example, the positions of the boom pin 91, the arm pin 92, and the bucket pin 93.

The target motion calculation unit 32 calculates the target motion of the work device 1B so that the bucket 10 moves without invading the target surface St, based on the information from the posture calculation unit 30, the target surface setting unit 37, and the operation detection device 34. do.

Specifically, the target motion calculation unit 32 is based on the target surface St set by the target surface setting unit 37, the calculation result (attitude information) of the attitude calculation unit 30, and the detection result (operation information) of the operation detection device 34. Then, the target speed of each actuator (5, 6, 7) is calculated. The target motion calculation unit 32 calculates the target speed of each actuator (5, 6, 7) in the machine control so that the work device 1B does not excavate the lower side of the target surface St. Hereinafter, a detailed description will be given with reference to FIG. FIG. 6 is a diagram showing an example of the locus of the tip portion of the bucket 10 when the tip portion of the bucket 10 is controlled according to the corrected target velocity vector Vca. In the description here, the Xt axis and the Yt axis are set as shown in FIG. The Xt axis is an axis parallel to the target surface St, and the Yt axis is an axis orthogonal to the target surface St.

The target motion calculation unit 32 calculates the primary target speed Vt1 of each actuator (5, 6, 7) based on the operation amount of the operation devices 15A, 15B, 15C. Next, the target motion calculation unit 32 receives the primary target speed Vt1 of each actuator (5, 6, 7), the attitude information of the hydraulic excavator 1 including the tip position Pb of the bucket 10 calculated by the attitude calculation unit 30, and the attitude information. The target speed vector Vca0 at the tip of the bucket 10 is calculated based on the dimensions (L1, L2, L3, etc.) of each part of the working device 1B stored in the ROM 20b. Further, the target motion calculation unit 32 is a distance in the Yt axis direction (target surface distance H) between the tip position Pb of the bucket 10 calculated by the attitude calculation unit 30 and the target surface St set by the target surface setting unit 37. ) Is calculated.

When the target surface distance H is smaller than the predetermined distance Ya1, the target motion calculation unit 32 has an actuator (5, 6) based on the target velocity vector Vca0 at the tip of the bucket 10 and the positional relationship between the target surface St and the bucket 10. , 7) Calculate the secondary target velocity Vt2. Specifically, the target motion calculation unit 32 has a component Vcay (velocity component in the Yt axis direction) perpendicular to the target surface St in the target velocity vector Vca0 at the tip of the bucket 10 as the target surface distance approaches 0 (zero). ) Is corrected to the required primary target velocity Vt1 of the actuators (5, 6, 7) so as to approach 0 (zero), and the secondary target velocity Vt2 is calculated to obtain the tip of the bucket 10. Control to convert the velocity vector to Vca (direction conversion control) is performed. When the target surface distance H is 0 (zero), the target velocity vector Vca is only the component Vcax (velocity component in the Xt axis direction) parallel to the target surface St. As a result, the tip end portion (control point) of the bucket 10 is held so as to be located at or above the target surface St.

For example, when the target motion calculation unit 32 operates the arm cloud independently and the target surface distance H becomes a predetermined distance Ya1 or less (that is, the target surface St and the target surface St are separated by Ya1 in the Yt axis direction). When the tip of the bucket 10 enters the set area formed by the surface), the arm cylinder 6 is extended and the boom cylinder 5 is extended to execute the direction change control for converting the velocity vector Vca0 into Vca. As described above, the predetermined distance Ya1 defines the width of the setting area in which the intervention control is executed. Therefore, the predetermined distance Ya1 is also referred to as the set width Ya1.

The direction change control may be executed by a combination of boom raising or boom lowering and an arm cloud, or may be executed by a combination of boom raising or boom lowering and an arm dump. In any case, when the tip of the bucket 10 is located above the target surface St and the target velocity vector Vca contains a downward component (Vcay <0) approaching the target surface St, the target motion calculation The unit 32 calculates the secondary target speed of the boom cylinder 5 in the boom raising direction that cancels the downward component. On the contrary, when the target velocity vector Vca includes an upward component (Vcay> 0) away from the target surface St, the target motion calculation unit 32 calculates the secondary target velocity of the boom cylinder 5 in the boom lowering direction that cancels the upward component. .. Further, when the target velocity vector Vca contains an upward component (Vcay> 0) approaching the target surface St in a state where the tip end portion of the bucket 10 is located below the target surface St, the target motion calculation unit 32 receives the target motion calculation unit 32. The secondary target speed of the boom cylinder 5 in the boom lowering direction that cancels the upward component is calculated. On the contrary, when the target velocity vector Vca includes an upward component (Vcay <0) away from the target surface St, the target motion calculation unit 32 calculates the secondary target velocity of the boom cylinder 5 in the boom raising direction that cancels the downward component. ..

The command value switching unit 39 shown in FIG. 4 sets the secondary target speed Vt2 calculated by the target operation calculation unit 32 as the command speed Vt of the actuators (5, 6, 7). Further, the command value switching unit 39 has a secondary target speed Vt2 calculated by the target operation calculation unit 32 for the command speed Vt of the actuator (5, 6, 7) based on the monitoring result of the distance monitoring unit 40 described later. To the primary target speed Vt1 or from the primary target speed Vt1 to the secondary target speed Vt2, the speed switching control that gradually changes with the passage of time is executed. The details of the speed switching control will be described later.

The solenoid valve control unit 33 outputs a command to the solenoid shutoff valve 61 and the solenoid proportional valve 500 based on the command speed Vt of the actuator (5, 6, 7) set by the command value switching unit 39. It controls the speed of the actuators (5, 6, 7).

An example of the operation of the hydraulic excavator 1 when the machine control is executed will be described with reference to FIG. 7. FIG. 7 is a diagram showing an example of a horizontal excavation operation by machine control.

At the start of excavation work, when the operator performs a boom lowering independent operation by the operating device 15A in order to arrange the bucket 10 at a predetermined position (excavation starting point), the controller 20 executes stop control. When the bucket 10 approaches the target surface St, the controller 20 controls the electromagnetic proportional valve 532 (see FIG. 3) so that the bucket 10 does not enter below the target surface St, and decelerates the speed of the boom 8. .. The controller 20 controls the electromagnetic proportional valve 532 (see FIG. 3) so that the speed of the boom 8 becomes zero when the bucket 10 reaches the target surface St.

When the operator operates the operating device 15B to perform horizontal excavation by the pulling motion (cloud motion) of the arm 9 in the arrow A direction, the controller 20 executes the area limitation control. The controller 20 controls the electromagnetic proportional valve 525 (see FIG. 3) so that the tip of the bucket 10 does not enter below the target surface St, and automatically raises the boom 8. At this time, in order to improve the excavation accuracy, the electromagnetic proportional valve 542 (see FIG. 3) is controlled to reduce the speed of the arm 9. The controller 20 controls the electromagnetic proportional valve 577 (see FIG. 3) so that the angle B of the bucket 10 with respect to the target surface St becomes a constant value and the leveling work becomes easy, and the bucket 10 automatically has an arrow C. It may rotate in a direction.

When the bucket 10 enters below the target surface St during horizontal excavation by pulling the arm 9 in the arrow A direction, the controller 20 causes the bucket 10 to return to the target surface St. , The electromagnetic proportional valve 525 (see FIG. 3) is controlled to automatically raise the boom 8.

In this way, when the machine control is effectively set by the MC switch 26, the controller 20 sets the target surface St, and the distance (target surface distance) H between the tip end portion of the bucket 10 and the target surface St is set. When it becomes smaller than the set width (first threshold value) Ya1, the operation of the working device 1B is controlled so that the bucket 10 does not excavate the ground beyond the target surface St.

When the target surface distance H is larger than the set width Ya1, the speed of the actuators (5, 6, 7) is controlled based on the operation command (pilot pressure) from the operating devices 15A, 15B, 15C. Therefore, when the target surface distance H is larger than the set width Ya1, the actuator (5, 6, 7) is controlled according to the operation of the operating devices 15A, 15B, 15C, which is referred to as manual control. On the other hand, when the target surface distance H is smaller than the set width Ya1, the controller 20 intervenes in the operation of the operating devices 15A, 15B, 15C by the operator and executes intervention control to control the operation of the working device 1B. .. In intervention control, the controller 20 controls the speed of the required actuators (5, 6, 7) by controlling the electromagnetic proportional valve 500 so that the bucket 10 does not excavate the ground beyond the target surface St.

By the way, depending on the positional relationship between the working device 1B and the target surface St, the target surface distance H may be significantly changed by the operation of the hydraulic excavator 1, and the intervention control and the manual control may be switched. For example, as shown in FIGS. 10A and 12A, when the tip portion of the bucket 10 moves above the target surfaces St1 and St2 having a height difference due to the operation of the working device 1B, the target surface distance H is set. It changes a lot.

Further, when the tip end portion of the bucket 10 is located above the region where the target surface does not exist, an invalid value ∞ is set for the target surface distance H. The invalid value ∞ is set to a value larger than the set width Ya1, the change amount determination value Hja described later, and the distance determination value Hjb. Therefore, as shown in FIG. 10B, when the tip portion of the bucket 10 moves from above the target surface St1 to above the region where the target surface does not exist due to the operation of the work device 1B, the target surface distance H is large. Change. As shown in FIG. 12B, when the working device 1B operates, the target surface distance H changes significantly even when the tip of the bucket 10 moves from above the region where the target surface does not exist to above the target surface St2. do.

When the intervention control and the manual control are switched due to a large change in the target surface distance H, the speed of the actuator (5, 6, 7) changes abruptly if the speed switching control described later is not executed. Along with this, a shock may occur.

The controller 20 according to the present embodiment monitors the distance between the bucket 10 and the target surface St (target surface distance H) and the amount of change thereof (distance change amount ΔH), and between the bucket 10 and the target surface St. Based on the distance (target surface distance H) and the amount of change (distance change amount ΔH), it is determined whether or not the following first and second conditions are satisfied, and the actuator is determined according to the determination result. The speed switching control that gradually changes the speed of (5, 6, 7) is executed.

The first condition is a condition for estimating the switch from intervention control to manual control, in which the distance change amount ΔH is larger than the change amount determination value Hja and the target surface distance H is larger than the distance judgment value Hjb. Sometimes it holds. The second condition is a condition for estimating the switch from manual control to intervention control, in which the distance change amount ΔH is larger than the change amount determination value Hja and the target surface distance H is smaller than the distance determination value Hjb. Sometimes it holds.

The controller 20 controls the speed of the actuator (5, 6, 7) when the intervention control is executed (that is, the secondary target speed Vt2 is set as the command speed Vt, and the command speed Vt is used as the command speed Vt. In the case), when the first condition is satisfied, the command speed Vt is gradually changed from the secondary target speed Vt2 to the primary target speed Vt1 according to the passage of time, so that the actuator (5, 6, 7) can be used. Gradually change the speed. Further, the controller 20 determines that the intervention control is not executed (that is, the speed of the actuator (5, 6, 7) is controlled based on the operation command from the operating devices 15A, 15B, 15C). When the second condition is satisfied, the speed of the actuator (5, 6, 7) is gradually changed by gradually changing the command speed Vt from the primary target speed Vt1 to the secondary target speed Vt2 according to the passage of time. Change.

Hereinafter, the content of the speed switching control will be described in detail with reference to FIGS. 4 and 8 to 13B. FIG. 8 is a diagram illustrating details of the function of the distance monitoring unit 40. As shown in FIG. 8, the distance monitoring unit 40 functions as a target surface selection unit 41, a target surface distance calculation unit 42, a distance change amount calculation unit 43, a distance determination unit 44, and a distance change amount determination unit 45.

The target surface selection unit 41 selects the target surface St to be calculated by the target surface distance calculation unit 42 from among the plurality of target surface Sts set by the target surface setting unit 37. In the present embodiment, the target surface selection unit 41 is in the vertical direction (direction of gravity) from the tip position Pb of the bucket 10 calculated by the attitude calculation unit 30 among the plurality of target surface Sts set by the target surface setting unit 37. ) Is selected as the target surface St on the straight line to be calculated.

The target surface distance calculation unit 42 calculates the distance (target surface distance) H in the direction perpendicular to the selected target surface St between the target surface St selected by the target surface selection unit 41 and the tip position Pb of the bucket 10. Calculate. The target surface distance calculation unit 42 repeatedly calculates the target surface distance H in a predetermined control cycle (that is, every predetermined time ct). When the target surface St is not selected by the target surface selection unit 41, the target surface distance calculation unit 42 sets an invalid value ∞ for the target surface distance H.

The distance change amount calculation unit 43 calculates the change amount (distance change amount) ΔH of the target surface distance H, which is repeatedly calculated by the target surface distance calculation unit 42 at predetermined time tc intervals. The distance change amount ΔH represents the change amount of the target surface distance H when a predetermined predetermined time tc has elapsed. The distance change amount ΔH is calculated by taking the absolute value of the difference between the target surface distance H2 calculated in the predetermined calculation cycle and the target surface distance H1 calculated in the previous calculation cycle (ΔH =). | H2-H1 |).

The distance change amount determination unit 45 determines whether or not the distance change amount ΔH calculated by the distance change amount calculation unit 43 is equal to or greater than the change amount determination value Hja. The change amount determination value Hja is a threshold value for determining (estimating) whether or not the intervention control and the manual control are switched, and is stored in the ROM 20b in advance. That is, the change amount determination value Hja determines (estimates) whether or not the tip portion of the bucket 10 moves in and out of the set area of the set width Ya1 where the machine control (intervention control) is executed. It can be said that it is the threshold value of. It is preferable that the change amount determination value (second threshold value) Hja is set to a value equal to or larger than the set width (first threshold value) Ya1.

The distance determination unit 44 determines whether or not the target surface distance H calculated by the target surface distance calculation unit 42 is equal to or greater than the distance determination value Hjb. The distance determination value Hjb is a threshold value for determining whether or not the tip of the bucket 10 is located within the setting area of the setting width Ya1 where machine control (intervention control) is executed, and is stored in the ROM 20b in advance. ing. The distance determination value (third threshold value) Hjb is preferably set to a value equal to or larger than the set width (first threshold value) Ya1. In the present embodiment, the same value is set for the change amount determination value Hja and the distance determination value Hjb. It should be noted that different values may be set for the change amount determination value Hja and the distance determination value Hjb.

The command value switching unit 39 shown in FIG. 4 has primary target speeds Vt1 and 2 calculated by the target motion calculation unit 32 based on the determination results of the distance change amount determination unit 45 and the distance determination unit 44 of the distance monitoring unit 40. One of the next target speeds Vt2 is set as the target value Vta of the command speed Vt.

The command value switching unit 39 determines that the distance change amount ΔH calculated by the distance change amount determination unit 45 is equal to or greater than the change amount determination value Hja, and the target surface distance H calculated by the target surface distance calculation unit 42. When it is determined that is equal to or greater than the distance determination value Hjb, it is considered that the first condition is satisfied (that is, it is estimated that the intervention control is switched to the manual control), and the primary target speed Vt1 is set as the target of the command speed Vt. Along with setting the value Vta, the secondary target speed Vt2 is set as the current command speed Vtc.

The command value switching unit 39 determines that the distance change amount ΔH calculated by the distance change amount determination unit 45 is equal to or greater than the change amount determination value Hja, and the target surface distance H calculated by the target surface distance calculation unit 42. If is determined to be less than the distance determination value Hjb, it is considered that the second condition is satisfied (that is, it is estimated that the manual control is switched to the intervention control), and the secondary target speed Vt2 is set as the target of the command speed Vt. Along with setting the value Vta, the primary target speed Vt1 is set as the current command speed Vtc.

When the first condition or the second condition is satisfied, the command value switching unit 39 calculates the speed difference ΔV by subtracting the current command speed Vtc from the target value Vta of the command speed Vt (ΔV = Vta-Vtc). The command value switching unit 39 calculates the time change rate (hereinafter, also referred to as the speed change rate) Vr of the speed by dividing the speed difference ΔV by the predetermined time Δta stored in the ROM 20b. The predetermined time Δta is a switching time between the speed at the time of intervention control and the speed at the time of manual control, and is predetermined by an experiment or the like. The command value switching unit 39 sets the command speed Vtc when the first condition or the second condition is satisfied as an initial value. The command value switching unit 39 calculates the command speed Vt based on the initial value Vtc, the speed change rate Vr, and the elapsed time t since the first condition or the second condition is satisfied (Vt = Vtc + Vr). × t), the calculated command speed Vt is output to the solenoid valve control unit 33.

In the present embodiment, when the hydraulic cylinders (5, 6, 7) operate in the extension direction, the primary target speed Vt1, the secondary target speed Vt2, and the command speed Vt are positive values. Therefore, when the hydraulic cylinders (5, 6, 7) operate in the extension direction and the speed change rate Vr is a positive value, the speed change rate Vr represents the speed increase rate, and the speed change rate Vr. When is a negative value, the rate of change in velocity Vr represents the rate of decrease in velocity.

In the present embodiment, when the hydraulic cylinders (5, 6, 7) operate in the contraction direction, the primary target speed Vt1, the secondary target speed Vt2, and the command speed Vt have negative values. Therefore, when the hydraulic cylinders (5, 6, 7) operate in the contraction direction and the speed change rate Vr is a negative value, the speed change rate Vr represents the speed increase rate, and the speed change rate Vr. When is a positive value, the rate of change in velocity Vr represents the rate of decrease in velocity.

With reference to the flowchart of FIG. 9, the content of the speed switching control performed by the controller 20 functioning as the distance monitoring unit 40 and the command value switching unit 39 will be described. FIG. 9 is a flowchart showing the contents of the speed switching control executed by the controller 20. The processing of the flowchart shown in FIG. 9 is started when the machine control is effectively set by the MC switch 26, and after the initial setting (not shown) is performed, the process is repeated in a predetermined control cycle (every tk for a predetermined time). Will be executed.

As shown in FIG. 9, in step S105, the target surface selection unit 41 selects the target surface St vertically below the tip of the bucket 10 from the plurality of target surface St, and proceeds to step S110. In step S110, the target surface distance calculation unit 42 calculates the distance (target surface distance) H between the target surface St selected in step S105 and the tip end portion of the bucket 10, and proceeds to step S120.

In step S120, the distance change amount calculation unit 43 takes the target surface distance H = H2 (current value) calculated in step S110 of the current calculation cycle and step S110 of the previous (for example, one previous) calculation cycle. By taking the absolute value of the difference from the calculated target surface distance H = H1 (previous value), the distance change amount ΔH is calculated (ΔH = | H2-H1 |), and the process proceeds to step S130.

In step S130, the distance change amount determination unit 45 determines whether or not the distance change amount ΔH calculated in step S120 is equal to or greater than the change amount determination value Hja. In step S130, if it is determined that the distance change amount ΔH is equal to or greater than the change amount determination value Hja, the process proceeds to step S140, and in step S130, it is determined that the distance change amount ΔH is less than the change amount determination value Hja. The process shown in the flowchart of 9 is terminated.

In step S140, the distance determination unit 44 determines whether or not the target surface distance H calculated in step S110 is equal to or greater than the distance determination value Hjb. If it is determined in step S140 that the target surface distance H is equal to or greater than the distance determination value Hjb, the process proceeds to step S150, and if it is determined in step S140 that the target surface distance H is less than the distance determination value Hjb, the process proceeds to step S160. move on.

In step S150, the command value switching unit 39 executes the first command value switching process and proceeds to step S170. In the first command value switching process (step S150), the command value switching unit 39 sets the primary target speed Vt1 of the actuator (5, 6, 7) to the actuator (5, 6) assuming that the first condition is satisfied. , 7) The target value Vta of the command speed Vt is set, and the secondary target speed Vt2 of the actuator (5, 6, 7) is set as the current command speed (initial value) Vtc. The secondary target speed Vt2 set as the current command speed Vtc is the secondary target speed Vt2 calculated by the target operation calculation unit 32 immediately before the first condition is satisfied. Further, the primary target speed Vt1 set as the target value Vta of the command speed Vt is the primary target speed Vt1 calculated by the target operation calculation unit 32 immediately after the first condition is satisfied. In the first command value switching process (step S150), the command value switching unit 39 calculates the speed change rate Vr.

In step S160, the command value switching unit 39 executes the second command value switching process, and proceeds to step S170. In the second command value switching process (step S160), the command value switching unit 39 sets the secondary target speed Vt2 of the actuator (5, 6, 7) to the actuator (5, 5, 7) assuming that the second condition is satisfied. The target value Vta of the command speed Vt of 6 and 7) is set, and the primary target speed Vt1 of the actuator (5, 6, 7) is set as the current command speed (initial value) Vtc. The primary target speed Vt1 set as the current command speed Vtc is the primary target speed Vt1 calculated by the target operation calculation unit 32 immediately before the second condition is satisfied. Further, the secondary target speed Vt2 set as the target value Vta of the command speed Vt is the secondary target speed Vt2 calculated by the target operation calculation unit 32 immediately after the second condition is satisfied. In the second command value switching process (step S160), the command value switching unit 39 calculates the speed change rate Vr.

In step S170, the command value switching unit 39 executes a speed calculation process that gradually changes the command speed Vt of the actuator (5, 6, 7) from the initial value Vtc to the target value Vta with the passage of time. The command value switching unit 39 calculates the command speed Vt based on the initial value Vtc, the speed change rate Vr, and the elapsed time t after the first condition or the second condition is satisfied. The speed calculation process (step S170) is completed when the command speed Vt reaches the target value Vta, and the process shown in the flowchart of FIG. 9 ends.

An example of the operation of this embodiment will be described. When the operator operates the MC switch 26 to enable machine control, the position and orientation of the swivel body 12 calculated based on the satellite signals received by the GNSS antennas 47a and 47b and the attitude detected by the attitude detection device 35. The target surface St is set based on the information.

As shown in FIG. 7, when the arm 9 is operated in the cloud by the operator performing the arm cloud independent operation with a predetermined operation amount (for example, the maximum operation amount), the target surface distance H is larger than the set width Ya1. If it is small, intervention control is executed in which the boom raising operation is performed so that the velocity vector at the tip of the bucket 10 in the direction perpendicular to the target surface St becomes zero. As a result, the tip of the bucket 10 moves along the target surface St. In the present embodiment, the deceleration control of the arm 9 is also performed in the intervention control. In the intervention control, the controller 20 calculates the secondary target speed Vt2 of the arm cylinder 6 whose absolute value | Vt2 | is smaller than the absolute value | Vt1 | of the primary target speed Vt1 of the arm cylinder 6, and the secondary target speed Vt2 of the arm cylinder 6. The target speed Vt2 is set as the command speed Vt of the arm cylinder 6, and the speed of the arm cylinder 6 is controlled based on the command speed of the arm cylinder 6.

Here, as shown in FIG. 10A, from the state in which the intervention control for moving the tip of the bucket 10 along the predetermined target surface St1 is executed, the bucket is above another target surface St2 having a large height difference. When the tip of 10 is located, the intervention control is released.

In the example shown in FIG. 10A, the target surface St selected by the controller 20 is changed from the target surface St1 to the target surface St2 set at a position lower than the target surface St1. In the example shown in FIG. 10A, the distance H between the target surface St1 calculated at the time point t1 and the tip of the bucket 10 is H1, and the distance H is calculated at the time point t2 after a predetermined time tc has elapsed from the time point t1. The distance H between the target surface St2 and the tip end portion of the bucket 10 is H2. (S105 → S110 → S120 in FIG. 9).

In the example shown in FIG. 10A, since the distance change amount ΔH is the change amount determination value Hja or more and the target surface distance H is the distance determination value Hjb or more (Y in step S130 of FIG. 9 → Y in S140). The first condition is satisfied. The controller 20 controls the speed of the actuator (5, 6, 7) when the intervention control is executed (that is, the secondary target speed Vt2 is set as the command speed Vt, and the command speed Vt is used as the command speed Vt. When the first condition is satisfied when the absolute value | Vt1 | of the primary target speed Vt1 is larger than the absolute value | Vt2 | of the secondary target speed Vt2, the command speed Vt is set to the secondary target speed. From Vt2 to the primary target speed Vt1, the speed is gradually increased with the passage of time (steps S150 and S170 in FIG. 9). That is, when the first condition is satisfied at the time point t2 (ta1), the controller 20 operates the command speed Vt of the arm cylinder 6 for the arm from the secondary target speed Vt2ac of the arm cylinder 6, as shown in FIG. 11A. The speed of the arm cylinder 6 is gradually increased by gradually increasing the primary target speed Vt1ac of the arm cylinder 6 according to the operation amount of the lever 15b with the passage of time. The command speed Vt of the arm cylinder 6 reaches the primary target speed Vt1ac at the time point ta2 after a predetermined time Δta has elapsed from the time point ta1. Further, the controller 20 controls the speed of the actuator (5, 6, 7) when the intervention control is executed (that is, the secondary target speed Vt2 is set as the command speed Vt, and the command speed Vt is used as the command speed Vt. When the first condition is satisfied when the absolute value | Vt1 | of the primary target speed Vt1 is smaller than the absolute value | Vt2 | of the secondary target speed Vt2, the command speed Vt is secondary. From the target speed Vt2 to the primary target speed Vt1, the speed is gradually reduced with the passage of time (steps S150 and S170 in FIG. 9). That is, when the first condition is satisfied at the time point t2 (ta1), the controller 20 sets the command speed Vt of the boom cylinder 5 from the secondary target speed Vt2br of the boom cylinder 5 to the primary target speed Vt1br (that is, 0). , The speed of the boom cylinder 5 is gradually reduced by gradually reducing it with the passage of time. The command speed Vt of the boom cylinder 5 reaches the primary target speed Vt1br (that is, 0) at the time point ta2.

Therefore, when the intervention control is released and the manual control is started, the speed of the arm cylinder 6 is prevented from suddenly increasing. As a result, it is possible to prevent the occurrence of a shock due to a rapid increase in the speed of the arm cylinder 6. Further, when the intervention control is released and the manual control is started, the speed of the boom cylinder 5 is prevented from suddenly decreasing. As a result, it is possible to prevent the occurrence of a shock due to a sudden decrease in the speed of the boom cylinder 5.

In the example shown in FIG. 10B, the target surface St1 is selected at the time point t1, but at the time point t2, the bucket 10 is removed from the area where the target surface exists, and the bucket 10 is above the area where the target surface does not exist. The tip of is located. Even in such a case, as shown in FIG. 11A, the command speed Vt of the arm cylinder 6 gradually increases from the secondary target speed Vt2ac to the primary target speed Vt1ac according to the operation amount of the arm operation lever 15b. Further, the command speed Vt of the boom cylinder 5 gradually decreases from the secondary target speed Vt2br to the primary target speed Vt1br (that is, 0).

Therefore, when the intervention control is released and the manual control is started, the speed of the arm cylinder 6 is prevented from suddenly increasing. As a result, it is possible to prevent the occurrence of a shock due to a rapid increase in the speed of the arm cylinder 6. Further, when the intervention control is released and the manual control is started, the speed of the boom cylinder 5 is prevented from suddenly decreasing. As a result, it is possible to prevent the occurrence of a shock due to a sudden decrease in the speed of the boom cylinder 5.

Next, intervention control (region limitation control) for decelerating the arm cylinder 6 and the boom cylinder 5 is executed by performing a combined operation of arm dump and boom lowering with a predetermined operation amount (for example, maximum operation amount). The change in the command speed when shifting from the state to manual control will be described. In this case, as shown in FIG. 11B, the magnitude (absolute value | Vt |) of the command speed Vt of the arm cylinder 6 is from the secondary target speed Vt2ad to the primary target speed Vt1ad according to the operation amount of the arm operation lever 15b. Gradually increase. Further, the magnitude (absolute value | Vt |) of the command speed Vt of the boom cylinder 5 gradually increases from the secondary target speed Vt2bl to the primary target speed Vt1bl. Therefore, when such an operation is performed, it is possible to prevent the occurrence of a shock due to a rapid increase in the speed of the arm cylinder 6 when shifting from the intervention control to the manual control. In addition, it is possible to prevent the occurrence of a shock due to a rapid increase in the speed of the boom cylinder 5.

Next, the command speed at the time of shifting from the state in which the intervention control (stop control) for decelerating the boom cylinder 5 to the manual control is performed by performing the combined operation of the turning operation and the boom lowering with a predetermined operation amount. The change of is explained. For example, when the tip of the bucket 10 deviates from the target surface St by a turning operation, the magnitude (absolute value | Vt |) of the command speed Vt of the boom cylinder 5 gradually changes from the secondary target speed Vt2bl to the primary target speed Vt1bl. To increase. Therefore, when such an operation is performed, it is possible to prevent the occurrence of a shock due to a rapid increase in the speed of the boom cylinder 5 when shifting from the intervention control to the manual control.

With reference to FIG. 12A, when the arm 9 is operated in the cloud by operating the arm cloud with a predetermined operation amount (for example, the maximum operation amount), the tip of the bucket 10 is above the target surface St1. An example in which intervention control is executed by locating the tip of the bucket 10 above another target surface St2 having a large height difference from the state where the portion is located will be described.

In the example shown in FIG. 12A, the distance change amount ΔH, which is the difference between the target surface distance H1 at the time point t1 and the target surface distance H2 at the time point t2, is equal to or more than the change amount determination value Hja, and the target surface distance H at the time point t2. Since (= H2) is less than the distance determination value Hjb (Y in step S130 of FIG. 9 and N in S140), the second condition is satisfied. The controller 20 is the case where the intervention control is not executed (that is, the speed of the actuator (5, 6, 7) is controlled based on the operation command from the operating devices 15A, 15B, 15C). When the second condition is satisfied, as shown in FIG. 13A, the command speed Vt of the arm cylinder 6 is changed from the primary target speed Vt1ac of the arm cylinder 6 according to the operation amount of the arm operation lever 15b to the secondary target of the arm cylinder 6. The speed of the arm cylinder 6 is gradually reduced by gradually reducing the speed up to Vt2ac with the passage of time.

Therefore, it is possible to prevent the speed of the arm cylinder 6 from suddenly decreasing when shifting from manual control to intervention control. As a result, it is possible to prevent the occurrence of a shock due to a sudden decrease in the speed of the arm cylinder 6.

As shown in FIG. 12B, when the tip of the bucket 10 is located above the region where the target surface St (St2) exists from the region where the target surface St does not exist, the first is the same as the example shown in FIG. 12A. Two conditions are met. Therefore, the command speed of the arm cylinder 6 gradually decreases from the primary target speed Vt1ac according to the operation amount of the arm operation lever 15b to the secondary target speed Vt2ac. Therefore, it is possible to prevent the speed of the arm cylinder 6 from suddenly decreasing when shifting from manual control to intervention control. As a result, it is possible to prevent the occurrence of a shock due to a sudden decrease in the speed of the arm cylinder 6.

Further, if the second condition is satisfied while the operator is operating the arm dump with a predetermined operation amount (for example, the maximum operation amount), the command speed of the arm cylinder 6 is as shown in FIG. 13B. The magnitude of Vt (absolute value | Vt |) gradually decreases from the primary target speed Vt1ad according to the operation amount of the arm operating lever 15b to the secondary target speed Vt2ad. Therefore, it is possible to prevent the occurrence of a shock due to a sudden decrease in the speed of the arm cylinder 6.

According to the above-described embodiment, the following effects are exhibited.

(1) The hydraulic excavator (working machine) 1 is attached to a vehicle body (machine) 1A and a vehicle body 1A, and has a plurality of driven members (8, 9, 10) including a bucket (working tool) 10 and a driven member ( Position information of the articulated work device 1B having a plurality of actuators (5, 6, 7) for driving 8, 9, 10), the operation devices 15A, 15B, 15C for operating the work device 1B, and the vehicle body 1A. 47, a posture detecting device 35 for detecting information about the posture of the hydraulic excavator 1, a target shape data acquired, the position information of the vehicle body 1A, and the posture of the hydraulic excavator 1 The target surface St is set based on the information, and when the target surface distance H, which is the distance between the bucket 10 and the target surface St, becomes smaller than the set width (first threshold value) Ya1, the bucket 10 becomes the target surface. It is provided with a controller (control device) 20 that executes intervention control to control the operation of the work device 1B by intervening in the operation of the operation devices 15A, 15B, 15C so as not to excavate the ground beyond St.

The controller 20 calculates the primary target speed Vt1 of the actuator (5, 6, 7) based on the operation amount of the operating devices 15A, 15B, 15C. When the target surface distance H is smaller than the set width Ya1, the controller 20 calculates the secondary target speed Vt2 of the actuator (5, 6, 7) based on the positional relationship between the target surface St and the bucket 10, and the secondary target. The speed Vt2 is set as the command speed Vt of the actuator (5, 6, 7), and the intervention control for controlling the speed of the actuator (5, 6, 7) is executed based on the command speed Vt.

The controller 20 monitors the target surface distance H and its change amount (distance change amount ΔH), and whether or not the first condition is satisfied based on the target surface distance H and its change amount (distance change amount ΔH). Is determined. The first condition is when the distance change amount ΔH is larger than the change amount determination value (second threshold value) Hja (ΔH> Hja) and the target surface distance H is larger than the distance determination value (third threshold value) Hjb ( H> Hjb). The change amount determination value (second threshold value) Hja and the distance determination value (third threshold value) Hjb are values of the set width (first threshold value) Ya1 or more (Hja ≧ Ya1, Hjb ≧ Ya1). The controller 20 controls the speed of the actuator (5, 6, 7) when the intervention control is executed (that is, the secondary target speed Vt2 is set as the command speed Vt, and the command speed Vt is used as the command speed Vt. When the first condition is satisfied when the absolute value | Vt1 | of the primary target velocity Vt1 is larger than the absolute value | Vt2 | of the secondary target velocity Vt2, the actuator (5, 6, 7) The command speed Vt of is gradually increased from the secondary target speed Vt2 to the primary target speed Vt1 with the passage of time.

According to this configuration, for example, as shown in FIG. 10A, when machine control (intervention control) is executed for the target surface St1, the bucket 10 is placed above another target surface St2 having a large height difference. When the tip is located, or as shown in FIG. 10B, when machine control (intervention control) is executed for the target surface St1, the tip of the bucket 10 is above the region where the target surface St does not exist. When the portion is positioned, the speed of the actuator (5, 6, 7) can be gradually increased from the secondary target speed Vt2 to the primary target speed Vt1. Therefore, according to the present embodiment, it is possible to prevent the occurrence of a shock due to a rapid increase in the speed of the driven member when the state in which the intervention control is executed is changed to the state in which the intervention control is not executed.

(2) The controller 20 controls the speed of the actuator (5, 6, 7) when the intervention control is executed (that is, the secondary target speed Vt2 is set as the command speed Vt, and the command speed Vt is used as the command speed Vt. When the first condition is satisfied when the absolute value | Vt1 | of the primary target velocity Vt1 is smaller than the absolute value | Vt2 | of the secondary target velocity Vt2, the actuator (5, 6) , 7) The command speed Vt is gradually decreased from the secondary target speed Vt2 to the primary target speed Vt1 with the passage of time.

According to this configuration, for example, as shown in FIG. 10A, when machine control (intervention control) is executed for the target surface St1, the bucket 10 is placed above another target surface St2 having a large height difference. When the tip is located, or as shown in FIG. 10B, when machine control (intervention control) is executed for the target surface St1, the tip of the bucket 10 is above the region where the target surface St does not exist. When the portion is positioned, the speed of the actuator (5, 6, 7) can be gradually reduced from the secondary target speed Vt2 to the primary target speed Vt1. Therefore, according to the present embodiment, it is possible to prevent the occurrence of a shock due to a sudden decrease in the speed of the driven member when the state in which the intervention control is executed is changed to the state in which the intervention control is not executed.

(3) The controller 20 determines whether or not the second condition is satisfied based on the target surface distance H and the amount of change thereof (distance change amount ΔH). The second condition is satisfied when the distance change amount ΔH is larger than the change amount determination value Hja and the target surface distance H is smaller than the distance determination value Hjb. The controller 20 is the second when the intervention control is not executed (that is, when the speed of the actuator (5, 6, 7) is controlled based on the operation command from the operating devices 15A, 15B, 15C). When the condition is satisfied, the command speed Vt of the actuator (5, 6, 7) is gradually changed from the primary target speed Vt1 to the secondary target speed Vt2 with the passage of time.

According to this configuration, for example, when the tip of the bucket 10 is located above the target surface St1 and above another target surface St2 having a large height difference, as shown in FIG. 12A, or as shown in FIG. 12B. When the tip of the bucket 10 is located above the area where the target surface St (St2) exists from above the area where the target surface St does not exist, the speed of the actuator (5, 6, 7) is set to the primary target speed. It can be gradually changed from Vt1 to the secondary target speed Vt2. Therefore, according to the present embodiment, it is possible to prevent the occurrence of a shock due to a sudden change in the speed of the driven member when the state in which the intervention control is not executed is changed to the state in which the intervention control is executed.

(4) The plurality of driven members have a boom 8 connected to the vehicle body 1A, an arm 9 connected to the boom 8, and a bucket 10 connected to the arm 9. The plurality of actuators (5, 6, 7) have a boom cylinder 5 for driving the boom 8, an arm cylinder 6 for driving the arm 9, and a bucket cylinder (working tool cylinder) 7 for driving the bucket (working tool) 10. ..

The controller 20 calculates the primary target speed Vt1 of the arm cylinder 6 based on the operation amount of the operating device 15B. The controller 20 is operated with respect to the arm 9 by the operating device 15B, and when the target surface distance H is smaller than the set width Ya1, the absolute value | Vt2 is larger than the absolute value | Vt1 | of the primary target speed Vt1 of the arm cylinder 6. | Is small. The secondary target speed Vt2 of the arm cylinder 6 is calculated, the secondary target speed Vt2 of the arm cylinder 6 is set as the command speed Vt of the arm cylinder 6, and the arm cylinder 6 is based on the command speed Vt of the arm cylinder 6. Perform intervention control to control the speed of. The controller 20 controls the speed of the arm cylinder 6 when the intervention control is being executed (that is, the secondary target speed Vt2 of the arm cylinder 6 is set as the command speed Vt of the arm cylinder 6 and the speed of the arm cylinder 6 is controlled based on this command speed Vt. When the first condition is satisfied, the command speed Vt of the arm cylinder 6 is changed from the secondary target speed Vt2 of the arm cylinder 6 to the primary target speed Vt1 of the arm cylinder 6 according to the passage of time. And gradually increase.

According to this configuration, as shown in FIG. 10A, when the machine control is executed for the target surface St1, when the tip of the bucket 10 is located above another target surface St2 having a large height difference. Alternatively, as shown in FIG. 10B, when machine control is executed for the target surface St1 and the tip of the bucket 10 is located above the region where the target surface St does not exist, the arm cylinder 6 The speed can be gradually increased from the secondary target speed Vt2 to the primary target speed Vt1. Therefore, according to the present embodiment, it is possible to prevent the occurrence of a shock due to a rapid increase in the speed of the arm 9 when the state in which the intervention control is executed is changed to the state in which the intervention control is not executed.

(5) The controller 20 satisfies the second condition when the intervention control is not executed (that is, when the speed of the arm cylinder 6 is controlled based on the operation command from the operation device 15B). Gradually reduces the command speed Vt of the arm cylinder 6 from the primary target speed Vt1 to the secondary target speed Vt2 of the arm cylinder 6 with the passage of time.

According to this configuration, as shown in FIG. 12A, when the tip of the bucket 10 is located above the target surface St1 and above another target surface St2 having a large height difference, or as shown in FIG. 12B. When the tip of the bucket 10 is located above the area where the target surface St (St2) exists from above the area where the target surface St does not exist, the speed of the arm cylinder 6 is changed from the primary target speed Vt1 to the secondary target speed Vt2. Can be gradually reduced to. Therefore, according to the present embodiment, it is possible to prevent the occurrence of a shock due to a sudden decrease in the speed of the arm 9 when the state in which the intervention control is not executed is changed to the state in which the intervention control is executed.

(6) Further, according to the present embodiment, the speed of the actuator (5,6,7) under intervention control is changed to the speed of the actuator (5,6,7) under manual control, or the speed of the actuator (5,6) under manual control. Since the speed of, 7) can be smoothly transitioned to the speed of the actuator (5, 6, 7) by intervention control, it is possible to suppress the operator from feeling uncomfortable.

The following modifications are also within the scope of the present invention, and it is possible to combine the configurations shown in the modifications with the configurations described in the above-described embodiment, or to combine the configurations described in the following different modifications. Is.

<Modification 1>
The controller (control device) 20 may have the function of the positioning calculation device 47c of the position detection device 47.

<Modification 2>
In the above embodiment, the case where the work machine is a crawler type hydraulic excavator 1 has been described as an example, but the present invention is not limited thereto. The present invention can be applied to various work machines equipped with an articulated work device such as a wheel type hydraulic excavator.

<Modification 3>
In the above embodiment, an example in which the operating devices 15A to 15D are hydraulic pilot type operating devices has been described, but the present invention is not limited thereto. An electric operation device may be provided, and the flow control valves 16a to 16d may be driven by the controller controlling the electromagnetic proportional valve based on the electric signal from the operation device. In this case, when the target surface distance H is larger than the set width Ya1, the controller 20 calculates the primary target speed Vt1 of the actuator (5, 6, 7) based on the operation amount of the operating devices 15A, 15B, 15C. The primary target speed Vt1 is set as the command speed Vt of the actuator (5, 6, 7), and the speed of the actuator (5, 6, 7) is controlled based on the command speed Vt.

<Modification example 4>
In the above embodiment, an example in which the actuator for driving the boom 8, the arm 9, and the bucket 10 is a hydraulic cylinder has been described, but the present invention is not limited thereto. The actuator that drives the boom 8, arm 9, and bucket 10 may be an electric cylinder.

<Modification 5>
The functions of the control device (controller 20) described in the above embodiment may be partially or wholly realized by hardware (for example, the logic for executing each function is designed by an integrated circuit).

Although the embodiments of the present invention have been described above, the above-described embodiments show only a part of the application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above-described embodiments. not.

1 ... Hydraulic excavator (working machine), 1A ... Body (machine), 1B ... Working equipment, 5 ... Boom cylinder (actuator), 6 ... Arm cylinder (actuator), 7 ... Bucket cylinder (actuator), 8 ... Boom (covered) Drive member), 9 ... Arm (driven member), 10 ... Bucket (working tool, driven member), 15A, 15B, 15C ... Operating device, 20 ... Controller (control device), 21, 22, 23, 24 ... Angle sensor (attitude sensor), 34 ... operation detection device, 35 ... attitude detection device, 36 ... target surface setting device, 47 ... position detection device, 61 ... electromagnetic shutoff valve, 500 ... electromagnetic proportional valve, H ... target surface distance ( Distance between the work tool and the target surface), Hja ... Change amount determination value (second threshold value), Hjb ... Distance determination value (third threshold value), St ... Target surface, Vt ... Command speed, Vt1 ... Primary target speed , Vt2 ... Secondary target speed, Vta ... Target value, Ya1 ... Set width (first threshold value), ΔH ... Distance change amount

Claims (5)

An articulated work device having a machine body, a plurality of driven members attached to the machine body including a work tool, and a plurality of actuators for driving the driven member, an operation device for operating the work device, and the above-mentioned. A position detection device that detects the position information of the machine, an attitude detection device that detects information about the posture of the work machine, and the target shape data acquired by acquiring the target shape data, the position information of the machine, and the work machine. The target surface is set based on the information on the posture, and when the distance between the work tool and the target surface becomes smaller than the first threshold value, the work tool does not excavate the ground beyond the target surface. As described above, in a work machine provided with a control device that performs intervention control that intervenes in the operation of the operation device and controls the operation of the work device.
The control device is
The primary target speed of the actuator is calculated based on the operation amount of the operating device.
When the distance between the work tool and the target surface is smaller than the first threshold value, the secondary target speed of the actuator is calculated based on the positional relationship between the target surface and the work tool, and the secondary target is calculated. The speed is set as the command speed of the actuator, and the intervention control for controlling the speed of the actuator based on the command speed is executed.
Monitor the distance between the work tool and the target surface and the amount of change thereof.
Based on the distance between the work tool and the target surface and the amount of change thereof, it is determined whether or not the first condition is satisfied.
When the intervention control is executed and the primary target speed is larger than the secondary target speed and the first condition is satisfied, the command speed of the actuator is set from the secondary target speed. Gradually increase over time to the primary target speed,
The first condition is satisfied when the amount of change in the distance is larger than the second threshold value and the distance between the work tool and the target surface is larger than the third threshold value.
The second threshold value and the third threshold value are values equal to or higher than the first threshold value.
A work machine characterized by that. In the work machine according to claim 1,
The control device is
When the intervention control is executed and the primary target speed is smaller than the secondary target speed and the first condition is satisfied, the command speed of the actuator is set from the secondary target speed. Gradually decrease over time to the primary target speed,
A work machine characterized by that. In the work machine according to claim 1,
The control device is
Based on the distance between the work tool and the target surface and the amount of change thereof, it is determined whether or not the second condition is satisfied.
When the second condition is satisfied when the intervention control is not executed, the command speed of the actuator is gradually changed from the primary target speed to the secondary target speed with the passage of time.
The second condition is satisfied when the amount of change in the distance is larger than the second threshold value and the distance between the work tool and the target surface is smaller than the third threshold value.
A work machine characterized by that. In the work machine according to claim 1,
The plurality of driven members include a boom connected to the machine body, an arm connected to the boom, and the work tool connected to the arm.
The plurality of actuators include a boom cylinder for driving the boom, an arm cylinder for driving the arm, and a work tool cylinder for driving the work tool.
The control device is
When the operation device operates the arm and the distance between the work tool and the target surface is smaller than the first threshold value, the arm cylinder is smaller than the primary target speed of the arm cylinder. The secondary target speed of the arm cylinder is calculated, the secondary target speed of the arm cylinder is set as the command speed of the arm cylinder, and the speed of the arm cylinder is controlled based on the command speed of the arm cylinder. Perform intervention control,
When the first condition is satisfied while the intervention control is being executed, the command speed of the arm cylinder is set from the secondary target speed of the arm cylinder to the primary target speed of the arm cylinder. Gradually increase over time,
A work machine characterized by that. In the work machine according to claim 3,
The plurality of driven members include a boom connected to the machine body, an arm connected to the boom, and the work tool connected to the arm.
The plurality of actuators include a boom cylinder for driving the boom, an arm cylinder for driving the arm, and a work tool cylinder for driving the work tool.
The control device is
When the operation device operates the arm and the distance between the work tool and the target surface is smaller than the first threshold value, the arm cylinder is smaller than the primary target speed of the arm cylinder. The secondary target speed of the arm cylinder is calculated, the secondary target speed of the arm cylinder is set as the command speed of the arm cylinder, and the speed of the arm cylinder is controlled based on the command speed of the arm cylinder. Perform intervention control,
If the second condition is satisfied when the intervention control is not executed, the command speed of the arm cylinder is set from the primary target speed of the arm cylinder to the secondary target speed of the arm cylinder. Gradually decrease over time,
A work machine characterized by that.

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