JP2018080510A - Work machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work machine capable of switching excavation by machine control and ordinary excavation as intended by the operator.SOLUTION: A hydraulic excavator 1 includes a controller 40 having an area limit control portion 43. The area limit control portion controls at least one of a plurality of hydraulic actuators 5, 6 and 7 so that a bucket 10 is positioned on or above the arbitrarily set target surface 60 while operating apparatus 45a, 45b, and 46 are being operated. The hydraulic excavator includes a control state change request switch 17 that is provided in the operation apparatus and capable of switching between validation and invalidation of control by the controller 40. The hydraulic excavator includes a sound output device 53B for generating sound at timing when the control by the controller 40 is switched between valid and invalid by the switch 17.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a work machine.

  There is a hydraulic excavator as a work machine including a work machine (hereinafter also referred to as a “front work machine”) composed of a work tool represented by a boom, an arm, and a bucket, each of which can rotate around a mounting pin. The hydraulic excavator includes a work machine and a vehicle body including an upper swing body and a lower traveling body. The base of the boom is supported by the upper swinging body so as to be rotatable about the mounting pin.

  Three links (driven members) of the boom, arm, and bucket are generated by a hydraulic pump driven by an engine mounted on the upper swing body for each hydraulic cylinder for the boom, arm, and bucket. It is driven by supplying the pressurized oil. When the operator operates the operation lever, the target link is driven to realize a desired movement of the working machine. Here, the operation to raise the boom is the boom raising operation, the lowering operation is the boom lowering operation, the arm turning operation is performed by extending the arm cylinder, the arm cloud operation is being performed, and the arm turning operation is performed by contracting the arm cylinder. The operation of rotating the bucket by extending the bucket cylinder is referred to as a bucket cloud operation, and the operation of rotating the bucket by contracting the bucket cylinder is referred to as a bucket dump operation. Hereinafter, the cloud operation is also referred to as excavation operation, and the dump operation is also referred to as earthing operation.

  In such a hydraulic excavator, the operation control of the work machine by the computer (control device) is intervened with the operation of the operation lever by the operator (semi-automatic control), or only by the operation control by the computer (fully automatic control), There is a function of controlling the operation of the work machine along a target plane (hereinafter also referred to as “design plane”) indicating the target shape of the excavation target (control that exhibits this function may be referred to as “region restriction control”) ). In addition, not only during excavation (hereinafter also referred to as “forming”) performed mainly by arm cloud operation, but also during alignment work by movement of the boom or bucket performed to move to the start position of the operation such as excavation, There is a function to stop the bucket on the target surface. Such a function of controlling the operation of the work machine automatically or semi-automatically with the intervention of the computer is called machine control.

  As an example relating to such a function of machine control, Patent Document 1 discloses an articulated front device constituted by a plurality of front members that can be rotated in the vertical direction, and a plurality of devices that drive the plurality of front members. The front device is provided in a construction machine having a hydraulic actuator and a plurality of hydraulic control valves that are driven by operation signals from a plurality of operation lever means and control flow rates of pressure oil supplied to the plurality of hydraulic actuators. In the front control device for a construction machine that corrects the operation signal so that the motor moves within a preset region and controls the operation of the front device (region limitation control), the lever grip of one of the plurality of operation lever means When the temporary release switch is pressed and the temporary release switch is pressed, the area restriction control of the front device is unified. And a region setting switch that is provided separately from the temporary release switch on the lever grip and that instructs setting of a region in which the front device can move. A control device is described.

Japanese Patent No. 3172447

  Patent Document 1 describes a front control device in which a temporary release switch for temporarily releasing area restriction control of the front device is provided on an operation lever. By disposing the temporary release switch in this way, it is possible to quickly and smoothly perform an operation in which excavation by area restriction control and normal excavation (excavation not by area restriction control) are used in combination.

  However, the front control device described in Patent Document 1 does not describe a notification means for notifying the operator that the area restriction control of the front device has been temporarily canceled. Therefore, if the operator operates the temporary release switch unintentionally while operating the operation lever, the operator cannot recognize that the area restriction control has been temporarily released, and the area restriction control is temporarily released unintentionally. There was a problem that.

  An object of the present invention is to easily switch between excavation by machine control (for example, excavation by area restriction control) and normal excavation, and switch between excavation by machine control and normal excavation as intended by the operator. It is to provide a work machine.

  The present application includes a plurality of means for solving the above-described problems. For example, a work machine having a boom, an arm and a work tool, a plurality of hydraulic actuators for driving the work machine, and an operator's operation. And a plurality of hydraulic actuators such that the work implement is positioned on or above an arbitrarily set target surface while the operation device is operated. In a work machine comprising a control device having a region restriction control unit that controls at least one of the first switch, the first switch provided in the operating device and capable of switching between valid and invalid control by the region restriction control unit; An audio output device that generates audio at a timing at which the control by the region restriction control unit is switched between valid and invalid by the first switch. To.

  According to the present invention, since the operator can surely recognize the switching timing between excavation by machine control and normal excavation, excavation by machine control and normal excavation can be switched as intended by the operator.

The block diagram of a hydraulic excavator. The figure which shows the control controller of a hydraulic shovel with a hydraulic drive device. Detailed view of the front control hydraulic unit. The hardware block diagram of the control controller of a hydraulic excavator. The figure which shows the coordinate system and target surface in the hydraulic shovel of FIG. The functional block diagram of the control controller of the hydraulic shovel of FIG. The functional block diagram of the area | region restriction | limiting control part in FIG. The figure which shows the relationship between the limit value ay and the distance D of the vertical component of bucket toe speed | velocity | rate. The figure which shows the example of the horizontal excavation operation | movement of the hydraulic shovel by machine control (area | region limitation control). The figure which shows the example of the operation lever provided with the machine control state change request switch. The figure which shows the example of a machine control changeover switch. The figure which shows the example of the display content of a display apparatus. The figure which shows the example of the display content of a display apparatus. The figure which shows the control flow of a control switching determination part. The figure which shows the control flow of a notification control part. The figure which shows the control flow of an area | region restriction | limiting control part and a solenoid valve control part.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following, a hydraulic excavator including the bucket 10 is illustrated as an attachment at the tip of the work machine, but the present invention may be applied to a hydraulic excavator including an attachment other than the bucket. Furthermore, as long as a plurality of driven members (attachment, arm, boom, etc.) are connected and have an articulated work machine that operates on a predetermined operation plane, it can be applied to a work machine other than a hydraulic excavator. Application is also possible.

  Also, in this article, regarding the meaning of the terms “upper”, “upper” or “lower” used with terms indicating a certain shape (eg, target surface, design surface, etc.), “upper” It means “surface”, “upper” means “a position higher than the surface” of the certain shape, and “lower” means “a position lower than the surface” of the certain shape. Further, in the following description, when there are a plurality of identical components, an alphabet may be added to the end of the code (number), but the alphabet may be omitted and the plurality of components may be described collectively. is there. For example, when there are three pumps 300a, 300b, and 300c, these may be collectively referred to as the pump 300.

<Basic configuration>
FIG. 1 is a configuration diagram of a hydraulic excavator according to an embodiment of the present invention, FIG. 2 is a diagram showing a control controller of the hydraulic excavator according to an embodiment of the present invention together with a hydraulic drive device, and FIG. 3 is a detailed view of a front control hydraulic unit 160. FIG.

  In FIG. 1, a hydraulic excavator 1 includes an articulated front work machine 1A and a vehicle body 1B. The vehicle body 1B includes a lower traveling body 11 that travels by left and right traveling motors 3a and 3b, and an upper revolving body 12 that is turnably mounted on the lower traveling body 11. The front work machine 1A is configured by connecting a plurality of driven members (boom 8, arm 9, and bucket 10) that rotate in the vertical direction, and the base end of the boom 8 of the front work machine 1A is turned upward. It is supported at the front of the body 12.

  An engine 18 that is a prime mover mounted on the upper swing body 12 drives the hydraulic pump 2 and the pilot pump 48. The hydraulic pump 2 is a variable displacement pump whose capacity is controlled by a regulator 2a, and the pilot pump 48 is a fixed displacement pump. In the present embodiment, a shuttle block 162 is provided in the middle of the pilot lines 144, 145, 146, 147, 148, 149. Hydraulic pressure signals output from the operating devices 45, 46 and 47 are also input to the regulator 2 a via the shuttle block 162. Although the detailed configuration of the shuttle block 162 is omitted, a hydraulic signal is input to the regulator 2a via the shuttle block 162, and the discharge flow rate of the hydraulic pump 2 is controlled according to the hydraulic signal.

  A pump line 148a, which is a discharge pipe of the pilot pump 48, passes through the lock valve 39, and then branches into a plurality of parts and is connected to the operating devices 45, 46, 47 and the valves in the front control hydraulic unit 160. The lock valve 39 is an electromagnetic switching valve in this example, and its electromagnetic drive unit is electrically connected to a position detector of a gate lock lever (not shown) disposed in the cab (FIG. 1). The position of the gate lock lever is detected by a position detector, and a signal corresponding to the position of the gate lock lever is input to the lock valve 39 from the position detector. If the position of the gate lock lever is in the locked position, the lock valve 39 is closed and the pump line 148a is shut off, and if it is in the unlocked position, the lock valve 39 is opened and the pump line 148a is opened. That is, in the state where the pump line 148a is shut off, the operation by the operation devices 45, 46, and 47 is invalidated, and operations such as turning and excavation are prohibited.

  The boom 8, the arm 9, the bucket 10, and the upper swing body 12 constitute driven members that are respectively driven by the boom cylinder 5, the arm cylinder 6, the bucket cylinder 7, and the swing hydraulic motor 4 (hydraulic actuator). Operation instructions to these driven members 8, 9, 10, and 12 are as follows: a traveling right lever 23a, a traveling left lever 23b, an operation right lever 1a, and an operation left lever 1b mounted in the driver's cab on the upper swing body 12 (these Are collectively referred to as operation levers 1 and 23).

  In the driver's cab, an operating device 47a having a traveling right lever 23a, an operating device 47b having a traveling left lever 23b, operating devices 45a and 46a sharing the operating right lever 1a, and an operating device sharing the operating left lever 1b. 45b and 46b are installed. The operation devices 45, 46, and 47 are hydraulic pilot systems, and the operation amounts (for example, lever strokes) and operation of the operation levers 1 and 23 operated by the operator based on the pressure oil discharged from the pilot pump, respectively. A pilot pressure (sometimes referred to as operation pressure) corresponding to the direction is generated. The pilot pressure generated in this way is supplied to the hydraulic drive units 150a to 155b of the corresponding flow control valves 15a to 15f (see FIG. 2) in the control valve unit 20 via the pilot lines 144a to 149b (see FIG. 2). And used as a control signal for driving these flow control valves 15a to 15f.

  The pressure oil discharged from the hydraulic pump 2 is supplied to the traveling right hydraulic motor 3a, the traveling left hydraulic motor 3b, the turning hydraulic motor 4, via the flow control valves 15a, 15b, 15c, 15d, 15e, 15f (see FIG. 2). It is supplied to the boom cylinder 5, arm cylinder 6 and bucket cylinder 7. The boom cylinder 5, the arm cylinder 6, and the bucket cylinder 7 are expanded and contracted by the supplied pressure oil, whereby the boom 8, the arm 9, and the bucket 10 are rotated, and the position and posture of the bucket 10 are changed. Further, the turning hydraulic motor 4 is rotated by the supplied pressure oil, whereby the upper turning body 12 is turned with respect to the lower traveling body 11. Further, the traveling right hydraulic motor 3a and the traveling left hydraulic motor 3b are rotated by the supplied pressure oil, so that the lower traveling body 11 travels.

  On the other hand, the boom angle sensor 30 is used for the boom pin, the arm angle sensor 31 is used for the arm pin, and the bucket is used for the bucket link 13 so that the rotation angles α, β, and γ (see FIG. 5) of the boom 8, arm 9, and bucket 10 can be measured. An angle sensor 32 is attached, and a vehicle body inclination angle sensor 33 that detects an inclination angle θ (see FIG. 5) in the front-rear direction of the upper turning body 12 (vehicle body 1B) with respect to a reference plane (for example, a horizontal plane) is attached to the upper turning body 12. It has been.

  The hydraulic excavator of this embodiment is provided with a control system that assists an operator's excavation operation. Specifically, when an excavation operation (specifically, at least one instruction of arm cloud, bucket cloud, and bucket dump) is input via the operation devices 45b and 46a, the target surface 60 (see FIG. 5) and Based on the positional relationship of the tip of the work machine 1A (in this embodiment, the tip of the bucket 10 is the tip of the bucket 10), the position of the tip of the work machine 1A is held on the target surface 60 and in the region above it. A control signal for forcibly operating at least one of 5, 6, 7 (for example, forcing the boom cylinder 5 to extend the boom) is output to the corresponding flow control valves 15a, 15b, 15c. A drilling control system is provided. In this paper, this control is sometimes referred to as “region restriction control” or “machine control”. By this control, the toes of the bucket 10 are prevented from entering below the target surface 60, so excavation along the target surface 60 is possible regardless of the level of skill of the operator. In the present embodiment, the control point related to the area restriction control is set at the tip of the bucket 10 of the excavator (the tip of the work machine 1A). The control point can be changed in addition to the bucket toe as long as it is a point at the tip of the work machine 1A. For example, the bottom surface of the bucket 10 or the outermost part of the bucket link 13 can be selected.

<Switches 17, 371, 393, display device 53A, audio output device 53B>
The excavation control system capable of executing the area restriction control is provided on a display device (for example, a liquid crystal display) 53A capable of displaying the positional relationship between the target surface 60 and the work implement 1A, and an operation lever 1a (operation device). Machine control state change request switch (first switch) 17 that can be switched between valid and invalid, and a machine control changeover switch (second switch) that is installed in the cab and can selectively select permission or prohibition of machine control 371, the timing at which the machine control valid / invalid state is changed by the voice output device (for example, speaker) 53B capable of outputting sound at the timing when the machine control valid / invalid state is changed, and the machine control state change request switch 17 Whether or not the audio output device 53B generates sound A selectable voice notification selection switch (third switch) 393, and a controller (control device) 40 area limiting control is executable computer.

  FIG. 10 is a configuration diagram of an operation lever 1a including a machine control state change request switch (first switch) 17. The machine control state change request switch 17 is provided on the back side of the grip portion of the joystick-shaped operation lever 1a, and is pressed by, for example, an index finger of an operator who holds the operation lever 1a. The machine control state change request switch 17 is a momentary switch that outputs a signal only while it is pressed. At the rising timing of the signal, a “machine control state change request flag” is sent to the control controller 40 (control switching determination unit 373). Output for one control cycle.

  FIG. 11 is a configuration diagram of the machine control changeover switch (second switch) 371. The machine control changeover switch 371 is a seesaw switch, and either machine control (MC) -ON (permitted) or machine control (MC) -OFF (prohibited) can be selected. The machine control changeover switch 371 can be provided in the driver's cab, and can be installed, for example, on a switch panel below the armrest on the side of the driver's seat in the driver's cab. The switch 371 does not have to be a seesaw switch, and any other switch can be used as long as it can switch between two positions.

  The voice notification selection switch (third switch) 393 has a position (sound ON position) where sound is generated by the sound output device 53B at the timing when the machine control valid / invalid state is changed, and a sound output by the sound output device 53B at the same timing. Can be switched to any of the positions where no sound is generated (voice OFF position). The voice notification selection switch (third switch) 393 can be provided in the cab. The voice notification selection switch (third switch) 393 may be installed as hardware, but the voice ON position and the OFF position can be switched from the menu screen of the display device 53A via the display device input device. May be.

<Front control hydraulic unit 160>
As shown in FIG. 3, the front control hydraulic unit 160 is provided in the pilot lines 144a and 144b of the operation device 45a for the boom 8, and detects the pilot pressure (first control signal) as the operation amount of the operation lever 1a. Pressure sensors 70a and 70b (see FIG. 3), and an electromagnetic proportional valve 54a (see FIG. 3) whose primary port side is connected to the pilot pump 48 via the pump line 148a to reduce and output the pilot pressure from the pilot pump 48. The pilot line 144a of the operating device 45a for the boom 8 and the secondary port side of the electromagnetic proportional valve 54a are connected to the pilot pressure in the pilot line 144a and the control pressure (second control signal) output from the electromagnetic proportional valve 54a. The high pressure side of the shuttle valve 82a (see FIG. 3) that leads to the hydraulic drive unit 150a of the flow control valve 15a is selected. And the electromagnetic proportionality which is installed in the pilot line 144b of the operating device 45a for the boom 8 and reduces the pilot pressure (first control signal) in the pilot line 144b based on the control signal from the controller 40 and outputs it. A valve 54b (see FIG. 3) is provided.

  The front control hydraulic unit 160 is installed in the pilot lines 145a and 145b for the arm 9, and detects a pilot pressure (first control signal) as an operation amount of the operation lever 1b and outputs it to the controller 40. 71a, 71b (see FIG. 3) and an electromagnetic proportional valve 55b (see FIG. 3) which is installed in the pilot line 145b and reduces and outputs the pilot pressure (first control signal) based on the control signal from the controller 40. And an electromagnetic proportional valve 55a (see FIG. 3) that is installed in the pilot line 145a and reduces and outputs the pilot pressure (first control signal) in the pilot line 145a based on a control signal from the controller 40. ing.

  Further, the front control hydraulic unit 160 detects a pilot pressure (first control signal) as an operation amount of the operation lever 1a in the pilot lines 146a and 146b for the bucket 10, and outputs the pressure sensor 72a to the controller 40. 72b (see FIG. 3), electromagnetic proportional valves 56a and 56b (see FIG. 3) that reduce and output pilot pressure (first control signal) based on the control signal from the controller 40, and the primary port side is pilot. Electromagnetic proportional valves 56c and 56d (see FIG. 3) connected to the pump 48 and reducing the pilot pressure from the pilot pump 48 for output, and pilot pressures in the pilot lines 146a and 146b and output from the electromagnetic proportional valves 56c and 56d. The high pressure side of the control pressure is selected and guided to the hydraulic drive units 152a and 152b of the flow control valve 15c. Yatoru valve 83a, and a 83 b (see FIG. 3) are provided. In FIG. 3, connection lines between the pressure sensors 70, 71, 72 and the controller 40 are omitted for the sake of space.

  The electromagnetic proportional valves 54 b, 55 a, 55 b, 56 a, and 56 b have a maximum opening when not energized, and the opening decreases as the current that is a control signal from the controller 40 is increased. On the other hand, the electromagnetic proportional valves 54a, 56c, and 56d have an opening degree of zero when not energized and an opening degree when energized, and the opening degree increases as the current (control signal) from the controller 40 increases. In this way, the opening 54, 55, 56 of each electromagnetic proportional valve corresponds to the control signal from the controller 40.

  An electromagnetic shut-off valve 61 is provided upstream of the proportional solenoid valves 54a, 56c, 56d in the pilot pipe 148a inside the front control hydraulic unit 160. When the solenoid valve 61 is not energized, the opening is zero, and when it is energized, the opening is fully opened. When machine control is executed, the electromagnetic shut-off valve 61 is energized by a control command from the controller 40, and when machine control is not executed, the electromagnetic shut-off valve 61 is de-energized by a control command from the controller 40.

  In the front control hydraulic unit 160 configured as described above, when the control signal is output from the controller 40 to drive the electromagnetic proportional valves 54a, 56c, 56d with the electromagnetic shut-off valve 61 fully open, Since pilot pressure (second control signal) can be generated even when there is no operator operation of 46a, boom raising operation, boom lowering operation, arm cloud operation, bucket cloud operation or bucket dump operation can be forcibly generated. Similarly, when the electromagnetic proportional valves 54b, 55a, 55b, 56a, 56b are driven by the controller 40, the pilot pressure (first control signal) generated by the operator operation of the operating devices 45a, 45b, 46a is reduced. The pilot pressure (second control signal) can be generated, and the speed of the boom lowering operation, the arm cloud / dump operation, and the bucket cloud / dump operation can be forcibly reduced as compared with the operator operation.

  In this paper, among the control signals for the flow control valves 15a to 15c, the pilot pressure generated by the operation of the operation devices 45a, 45b, and 46a may be referred to as a “first control signal”. Of the control signals for the flow control valves 15a to 15c, the pilot pressure generated by correcting (reducing) the first control signal by driving the electromagnetic proportional valves 54b, 55a, 55b, 56a, 56b by the controller 40. The pilot pressure newly generated separately from the first control signal by driving the electromagnetic proportional valves 54b, 55a, 55b, 56a, 56b by the controller 40 may be referred to as a “second control signal”. When the first control signal is generated for one hydraulic drive unit and the second control signal is generated for the other hydraulic drive unit in the same flow control valve 15a to 15c, the second control signal is given priority. The first control signal is blocked by an electromagnetic proportional valve, and the second control signal is input to the other hydraulic drive unit. When the first control signal and the second control signal are defined in this way, the above-mentioned “region restriction control” or “machine control” can be said to be control of the flow control valves 15a to 15c based on the second control signal.

<Oil temperature sensor 590, rotation speed sensor 490>
In FIG. 3, an oil temperature sensor 590 for detecting the temperature of the hydraulic oil pumped up from the tank by the pilot pump 48 is provided at a position downstream of the lock valve 39 and upstream of the front control hydraulic unit 160 in the pilot pipe 148a. ing. In FIG. 2, a rotation speed sensor 490 that detects the rotation speed of the engine 18 is provided on the output shaft of the engine 18.

<Control controller 40>
FIG. 4 shows a hardware configuration of the control controller 40. The controller 40 includes an input unit 91, a central processing unit (CPU) 92 that is a processor, a read-only memory (ROM) 93 and a random access memory (RAM) 94 that are storage devices, and an output unit 95. ing. The input unit 91 includes signals from the angle sensors 30 to 32 and the tilt angle sensor 33 that are the work machine attitude detection device 50, a signal from the target surface setting device 51 that is a device for setting the target surface 60, and a machine A pressure sensor (pressure sensor) that detects a signal from the control state change request switch (first switch) 17, a signal from the machine control changeover switch (second switch) 371, and an operation amount from the operating devices 45a, 45b, and 46a. 70, 71, 72), a signal from the operator operation detection device 52a, a signal from the voice notification selection switch (third switch) 393, and signals from the rotation speed sensor 490 and the oil temperature sensor 590, Conversion is performed so that the CPU 92 can perform computation. The ROM 93 is a recording medium in which a control program for executing area restriction control including processing related to a flowchart described later and various information necessary for the execution of the flowchart are stored. The CPU 92 is stored in the ROM 93. Predetermined arithmetic processing is performed on signals taken from the input unit 91 and the memories 93 and 94 according to the control program. The output unit 95 creates a signal for output according to the calculation result in the CPU 92, and outputs the signal to the electromagnetic proportional valves 54 to 56, the electromagnetic cutoff valve 61, the display device 53A, or the audio output device 53B. The voice output device drives / controls the hydraulic actuators 5 to 7, displays images of the vehicle body 1 </ b> B, the bucket 10, the target surface 60, and the like on the display screen of the display device 53 </ b> A, or switches the valid / invalid state of the machine control. Sound is output via 53B.

  4 includes semiconductor memories such as ROM 93 and RAM 94 as storage devices. However, the control controller 40 may be replaced with any other storage device, and may include a magnetic storage device such as a hard disk drive.

  FIG. 6 is a functional block diagram of the controller 40 according to the embodiment of the present invention. The control controller 40 includes a region restriction control unit 43, a solenoid valve control unit 44, a control switching determination unit 373, and a notification control unit 374.

  To the area restriction control unit 43, a work implement attitude detection device 50, a target surface setting device 51, and an operator operation detection device 52a are connected.

  The work machine attitude detection device 50 includes a boom angle sensor 30, an arm angle sensor 31, a bucket angle sensor 32, and a vehicle body tilt angle sensor 33.

  The target surface setting device 51 is an interface through which information regarding the target surface 60 (including position information and inclination angle information of each target surface) can be input. The input of the target surface via the target surface setting device 51 may be performed manually by the operator or may be taken in from the outside via a network or the like. The target plane setting device 51 is connected to a satellite communication antenna (not shown) such as a GNSS receiver. If the excavator can communicate with an external terminal that stores 3D data of the target plane defined on the global coordinate system (absolute coordinate system), the excavator is based on the global coordinates of the excavator specified by the satellite communication antenna. The target plane corresponding to the position can be searched and captured in the three-dimensional data of the external terminal.

  The operator operation detection device 52a is a pressure sensor 70a, 70b, 71a, 71b, which acquires an operation pressure generated in the pilot lines 144, 145, 146 when the operator operates the operation levers 1a, 1b (operation devices 45a, 45b, 46a). 72a and 72b. That is, the operation with respect to the hydraulic cylinders 5, 6, and 7 related to the work machine 1A is detected.

<Control switching determination unit 373>
Based on outputs from the machine control state change request switch (first switch) 17, the machine control changeover switch (second switch) 371, the rotational speed sensor 490, and the oil temperature sensor 590, the control switching determination unit 373 performs machine control ( This is a part for executing processing for determining whether or not to switch between valid / invalid states of (region restriction control). The control switching determination unit 373 outputs a control command corresponding to the determination result to the region restriction control unit 43 and the solenoid valve control unit 44, and flags (machine control state valid change flag and machine control state invalid change flag corresponding to the determination result). ) To the notification control unit 374. The process performed by the control switching determination unit 373 will be described later with reference to FIG.

<Notification control unit 374>
The notification control unit 374 is based on the output from the control switching determination unit 373 (machine control state valid change flag and machine control state invalid change flag) and the output from the voice notification selection switch (third switch) 393. This is the part that controls the display device 53A and the audio output device 53B. The notification control unit 374 includes a voice control unit 374b that controls the voice output device 53B and a display control unit 374a that controls the display device 53A.

  The voice control unit 374b is provided with a voice ROM that stores a large number of voice data. The voice control unit 374b reads a predetermined program from the control switching determination unit 373 based on the flag and the output from the switch 393. At the same time, audio output control is performed in the audio output device 53B. The process performed by the voice control unit 374b will be described later with reference to FIG.

  The display control unit 374a includes a display ROM that stores a large number of display-related data including icons. The display control unit 374a reads a predetermined program based on a flag from the control switching determination unit 373. Then, display control is performed in the display device 53A. Specifically, when the machine control state valid change flag is input from the control switching determination unit 373, the display control unit 374a indicates that the machine control state is valid on the display screen 391 as shown in FIG. An icon 394 is displayed. On the other hand, when the machine control state invalid change flag is input from the control switching determination unit 373, the display control unit 374a hides the icon 394 on the display screen 391 as shown in FIG. The display screen 391 in FIGS. 12 and 13 includes a longitudinal sectional view (side view of the bucket 10) of the target surface 60 and a toe position of the bucket 10 for notifying the operator of the positional relationship between the target surface 60 and the bucket 10. A cross-sectional view of the target surface 60 is displayed. In place of the display in FIGS. 12 and 13, an icon (not shown) indicating that the machine control state is invalid is displayed on the screen 391 in FIG. 13, and the icon is not displayed on the screen 391 in FIG. Anyway.

<Processing performed by control switching determination unit 373>
FIG. 14 is a flowchart of a series of processes performed by the control switching determination unit 373. This flowchart is repeated at a predetermined control period while the power of the hydraulic excavator is turned on. When the flowchart of FIG. 14 is started, the control switch determination unit 373 first switches the machine control switch (second switch) 371 to the ON state (the position “MC-ON” in FIG. 11) in step S01. Is determined). If it is ON, the process proceeds to step S02.

  In step S02, it is determined whether a machine control state change flag is input from the machine control state change request switch (first switch) 17 or not. If it is determined that the machine control state change flag has been input, the process proceeds to step S03.

  In step S03, information indicating whether or not the current machine control state stored in the state ROM provided in the control switching determination unit 373 is valid or invalid is read, and whether or not the current machine control state is valid or invalid. Determine. Note that the initial value of the information in the state ROM (the value when the excavator power is turned on and the value when the machine control changeover switch 371 is MC-OFF) is “invalid”, and thereafter, in steps S06 and S10 described later. Rewritten.

  If it is determined in step S03 that the machine control state is invalid, the process proceeds to step S04. In step S04, it is determined whether or not the engine speed is greater than or equal to a predetermined value N1 based on the input value from the speed sensor 490.

  The predetermined value N1 will be described. As is apparent from the function of the region restriction control unit 43 shown in FIG. 7, in the machine control, the cylinder speed by the operator operation is calculated from the pilot pressure (the operation amount by the operator) (mainly the cylinder speed calculation unit 43d in FIG. 7). The target pilot pressure is calculated from the target cylinder speed by machine control calculated based on this (mainly the processing of the target pilot pressure calculation unit 43h in FIG. 7). That is, in the machine control, the correlation between the pilot pressure and the cylinder speed is used, but the relationship between the two varies depending on the engine speed that affects the discharge flow rate of the hydraulic pump 2. Therefore, the predetermined value N1 is set to such a value that the machine control accuracy and responsiveness are not affected by the fluctuation. For example, as the value of the predetermined value N1, a design value of the pump discharge flow rate used in machine control is taken into consideration, and a minimum value of the engine speed that can be achieved by the design value or an arbitrary value higher than that can be used as N1.

  If it is determined in step S04 that the engine speed is greater than or equal to the predetermined value N1, the process proceeds to step S05. In step S05, it is determined based on the input value from the oil temperature sensor 590 whether the hydraulic oil temperature is equal to or higher than a predetermined value T1.

  The predetermined value T1 will be described. As described above, the correlation between the pilot pressure and the cylinder speed is used in the machine control, but the relationship between the two varies depending on the discharge flow rate of the hydraulic pump 2 and the hydraulic oil viscosity that affects the response of the pilot pressure. Therefore, the value of the hydraulic oil viscosity that does not affect the accuracy of machine control due to the fluctuation is expressed by the hydraulic oil temperature, and the minimum value of the hydraulic oil temperature or an arbitrary value higher than that is defined as the predetermined value T1.

  If it is determined in step S05 that the hydraulic oil temperature is equal to or higher than the predetermined value T1, the process proceeds to step S06. In step S06, the control switching determination unit 373 rewrites the machine control state in the state ROM from invalid to “valid”, and outputs that the current machine control state is valid to the area restriction control unit 43, and proceeds to step S07. move on. In step S07, the control switching determination unit 373 outputs a “machine control state valid change flag” to the notification control unit 374.

  On the other hand, if it is determined in step S01 that the machine control changeover switch 371 is not in the ON state (a state in which the machine control changeover switch 371 is switched to the “MC-OFF” position in FIG. 11), nothing is done (step S08). Return to S01.

  If it is determined in step S02 that the machine control state change request flag has not been input, the process proceeds to step S09, the current machine control state is maintained, and the process returns to step S01. If it is determined in step S04 that the engine speed is not equal to or higher than the predetermined value N1, and if it is determined in step S05 that the oil temperature is not equal to or higher than the predetermined value T1, the process proceeds to step S09, and the current machine Maintain control.

  If it is determined in step S03 that the current state is machine control enabled, the process proceeds to step S10. In step S10, the control switching determination unit 373 rewrites the machine control state in the state ROM from valid to “invalid”. Then, the control switching determination unit 373 issues a command to the region restriction control unit 43 so that the target cylinder speed calculation unit 43g outputs the calculation result of the cylinder speed calculation unit 43d to the target pilot pressure calculation unit 43h. Further, the control switching determination unit 373 issues a command to the electromagnetic valve control unit 44 so that the opening degree of the electromagnetic cutoff valve 61 is zero, and the process proceeds to step S11. In step 11, the control switching determination unit 373 outputs a “machine control state invalid change flag” to the notification control unit 374, and the process returns to step S01.

<Processing performed by notification control unit 374>
FIG. 15 is a flowchart of a series of processes performed by the notification control unit 374. This flowchart is repeated at a predetermined control cycle while the power of the hydraulic excavator is turned on. When the flowchart of FIG. 15 is started, the notification control unit 374 first, in step SA01, the voice output device 53B causes the voice notification selection switch (third switch) 393 to change the valid / invalid state of the machine control. It is determined whether or not the position has been switched to a position where sound is generated (voice ON position). If the switch 393 is in the voice ON position, the process proceeds to step SA02.

  In step SA02, it is determined whether or not the “machine control state valid change flag” output in step S07 of FIG. If it is determined that this flag has been input, the process proceeds to step SA03, where the sound control unit 374b outputs a signal (sound) indicating the machine control state valid change from the sound output device 53B. An example of the signal at that time is intermittent sound. Thus, by outputting intermittent sounds from the audio output device 53B, the operator can be surely recognized that the machine control state has been effectively changed. When step SA03 ends, the process returns to step SA01.

  If it is determined in step SA02 that the machine control state valid change flag has not been input, the process proceeds to step SA04. In step SA04, it is determined whether or not the “machine control state invalid change flag” output in step S11 of FIG. When it is determined that this flag is input, the process proceeds to step SA05, and the sound control unit 374b outputs a signal (sound) indicating the machine control state invalid change from the sound output device 53B. An example of the signal at that time is a continuous sound. Thus, by outputting a continuous sound from the audio output device 53B, the operator can be surely recognized that the machine control state has changed to invalid. When step SA05 ends, the process returns to step SA01.

  If it is determined in step SA04 that the machine control state invalid change flag has not been input, and if it is determined in step SA01 that the switch 393 is not in the voice ON position, the process proceeds to step SA06. In step SA06, nothing is output from the audio output device 53B, and the process returns to step SA01.

<Area Limit Control Unit 43, Solenoid Valve Control Unit 44>
FIG. 7 is a functional block diagram of the area restriction control unit 43 in FIG. The region restriction control unit 43 includes an operation amount calculation unit 43a, a posture calculation unit 43b, a target surface calculation unit 43c, a cylinder speed calculation unit 43d, a bucket tip speed calculation unit 43e, and a target bucket tip speed calculation unit 43f. A target cylinder speed calculation unit 43g and a target pilot pressure calculation unit 43h are provided.

  The operation amount calculator 43a calculates the operation amounts of the operation devices 45a, 45b, and 46a (operation levers 1a and 1b) based on the input from the operator operation detection device 52a. The operation amounts of the operating devices 45a, 45b, 46a can be calculated from the detected values of the pressure sensors 70, 71, 72.

  The calculation of the operation amount by the pressure sensors 70, 71, 72 is merely an example. For example, a position sensor (for example, a rotary encoder) that detects the rotational displacement of the operation lever of each operation device 45a, 45b, 46a The operation amount may be detected. In addition, instead of the configuration for calculating the operation speed from the operation amount, a stroke sensor for detecting the expansion / contraction amount of each hydraulic cylinder 5, 6, 7 is attached, and the operation speed of each cylinder is determined based on the time change of the detected expansion / contraction amount. The structure to calculate is also applicable.

  The posture calculation unit 43b calculates the posture of the work implement 1A and the position of the toe of the bucket 10 based on information from the work implement posture detection device 50. The posture of the work machine 1A can be defined on the shovel coordinate system of FIG. The shovel coordinate system of FIG. 5 is a coordinate system set for the upper swing body 12, and the base portion of the boom 8 that is rotatably supported by the upper swing body 12 is the origin, and the vertical direction in the upper swing body 12. Z axis and X axis in the horizontal direction were set. The inclination angle of the boom 8 with respect to the X-axis is the boom angle α, the inclination angle of the arm 9 with respect to the boom 8 is the arm angle β, and the inclination angle of the bucket toe relative to the arm is the bucket angle γ. The inclination angle of the vehicle body 1B (upper turning body 12) with respect to the horizontal plane (reference plane) is defined as an inclination angle θ. The boom angle α is detected by the boom angle sensor 30, the arm angle β is detected by the arm angle sensor 31, the bucket angle γ is detected by the bucket angle sensor 32, and the tilt angle θ is detected by the vehicle body tilt angle sensor 33. As defined in FIG. 5, if the lengths of the boom 8, the arm 9, and the bucket 10 are L1, L2, and L3, respectively, the coordinates of the bucket toe position in the shovel coordinate system and the posture of the work machine 1A are L1, L2, and L3. , Α, β, γ.

  The target surface calculation unit 43 c calculates the position information of the target surface 60 based on the information from the target surface setting device 51 and stores this in the ROM 93. In the present embodiment, as shown in FIG. 5, a cross-sectional shape obtained by cutting a three-dimensional target surface with a plane on which the work machine 1A moves (an operation plane of the work machine) is used as the target surface 60 (two-dimensional target surface). To do.

  The cylinder speed calculator 43d calculates the operating speed (cylinder speed) of each of the hydraulic cylinders 5, 6, and 7 based on the operation amount (first control signal) calculated by the operation amount calculator 43a. The operating speed of each hydraulic cylinder 5, 6 and 7 includes the operation amount calculated by the operation amount calculating unit 43a, the characteristics of the flow control valves 15a, 15b and 15c, and the cross-sectional area of each hydraulic cylinder 5, 6 and 7. It can be calculated from the pump flow rate (discharge amount) obtained by multiplying the capacity (tilt angle) of the hydraulic pump 2 and the rotational speed.

  The bucket tip speed calculator 43e is operated by an operator based on the operating speed of each of the hydraulic cylinders 5, 6, and 7 calculated by the cylinder speed calculator 43d and the attitude of the work implement 1A calculated by the attitude calculator 43b. The speed vector B of the bucket tip (toe) according to (first control signal) is calculated. The velocity vector B at the tip of the bucket can be decomposed into a component bx that is horizontal to the target surface 60 and a component by that is perpendicular to the target surface 60, based on information about the target surface 60 input from the target surface calculation unit 43c.

  The target bucket tip speed calculator 43f calculates a target speed vector T of the bucket tip (toe). For this purpose, the target bucket tip speed calculator 43f first sets the speed vector of the bucket tip on the target surface 60 based on the distance D (see FIG. 5) from the bucket tip to the target surface 60 to be controlled and the graph of FIG. The limit value ay of the vertical component is calculated. The calculation of the limit value ay is carried out by storing it in the ROM 93 of the controller 40 in the form of a function or table defining the relationship between the limit value ay and the distance D as shown in FIG. . The distance D can be calculated from the position (coordinates) of the toe of the bucket 10 calculated by the posture calculation unit 43 b and the distance of a straight line including the target surface 60 stored in the ROM 93. The relationship between the limit value ay and the distance D preferably has a characteristic that the limit value ay monotonously decreases as the distance D increases, but is not limited to that shown in FIG. For example, the limit value ay may be held at an individual predetermined value when the distance D is greater than or equal to a positive predetermined value or less than a negative predetermined value, or the relationship between the limit value ay and the distance D is defined by a curve. Also good.

  Next, the target bucket tip speed calculation unit 43f obtains a component by perpendicular to the target surface 60 of the bucket tip speed vector B, and based on the magnitude relationship between the vertical component by and the positive / negative of the limit value ay and the absolute value, An expression necessary for calculating a component cy perpendicular to the target surface 60 of the speed vector C of the bucket tip to be generated by the operation of the boom 8 by machine control is selected (the expression selection process will be described later with reference to FIG. 16). To do). Then, the vertical component cy is calculated from the selected expression, the horizontal component cx is calculated from the motion permitted to the boom when the vertical component cy is generated, and the target speed is calculated from the speed vectors B and C and the limit value ay. A vector T is calculated. Hereinafter, in the target velocity vector T, a component perpendicular to the target surface 60 is ty and a horizontal component is tx, and the derivation process of the target vector T will be described later with reference to FIG.

  The target cylinder speed calculator 43g calculates the target speeds of the hydraulic cylinders 5, 6, and 7 based on the target speed vector T (tx, ty) calculated by the target bucket tip speed calculator 43f. In this embodiment, the target speed vector T is defined by the sum of the speed vector B by the operator operation and the speed vector C by the machine control, so that the target speed of the boom cylinder 5 can be calculated from the speed vector C. As a result, the target speed vector T at the bucket tip becomes a combined value of the speed vectors that appear at the bucket tip when the hydraulic cylinders 5, 6, and 7 are operated at the target speed. When the vertical component cy of the speed vector C by machine control is zero, the target cylinder speed calculation unit 43g uses the hydraulic cylinders 5, 6, 6 based on the bucket tip speed vector B calculated by the bucket tip speed calculation unit 43e. 7 target speed is calculated.

  When the machine control state is “valid” in the control switching determination unit 373, the target cylinder speed calculation unit 43g outputs the above calculation result to the target pilot pressure calculation unit 43h. On the other hand, when the machine control state is “invalid”, the control switching determination unit 373 causes the target cylinder speed calculation unit 43g to calculate the target pilot pressure calculation result of the cylinder speed calculation unit 43d with respect to the region restriction control unit 43. Command to output to the unit 43h. Further, the control switching determination unit 373 issues a command to the electromagnetic valve control unit 44 so that the opening degree of the electromagnetic cutoff valve 61 is zero.

  The target pilot pressure calculation unit 43h supplies the flow control valves 15a, 15b, and 15c to the hydraulic cylinders 5, 6, and 7 based on the target speeds of the cylinders 5, 6, and 7 calculated by the target cylinder speed calculation unit 43g. Calculate the target pilot pressure. Then, the calculated target pilot pressure of each hydraulic cylinder 5, 6, 7 is output to the solenoid valve control unit 44.

  The electromagnetic valve control unit 44 calculates commands to the electromagnetic proportional valves 54 to 56 based on the target pilot pressures to the flow control valves 15a, 15b, and 15c calculated by the target pilot pressure calculation unit 43h. Further, when the machine switching state is “invalid” in the control switching determination unit 373, the electromagnetic valve control unit 44 outputs a command to make the opening degree of the electromagnetic cutoff valve 61 zero, and the pilot pump 48 outputs the lock valve 39. Is prevented from flowing into the front control hydraulic unit 160. And, for the electromagnetic proportional valves 54b, 55a, 55b, 56a, 56b whose opening degree is fully opened when de-energized, a command to keep the de-energization and fully open the opening degree is output. Do not intervene in pressure. Further, for the electromagnetic proportional valves 54b, 55a, 55b, 56a, and 56b, whose opening degree is zero when de-energized, a command to maintain de-energization and set the opening degree to zero is output. The front work machine 1A is prevented from operating. On the other hand, when the machine switching state is “valid” in the control switching determination unit 373, a command to fully open the opening of the electromagnetic shut-off valve 61 is output.

  If the pilot pressure (first control signal) based on the operator operation matches the target pilot pressure calculated by the target pilot pressure calculation unit 43h, the current value (command) to the corresponding electromagnetic proportional valves 54 to 56 is determined. Value) becomes zero, and the operation of the corresponding electromagnetic proportional valves 54 to 56 is not performed.

<Machine control flowchart>
FIG. 16 is a flowchart of area restriction control (machine control) executed by the controller 40. The controller 40 starts the flowchart of FIG. 16 when an operation by the operator is detected by the operation amount calculator 43a.

  In S410, the cylinder speed calculation unit 43d calculates the operation speed (cylinder speed) of each hydraulic cylinder 5, 6, and 7 based on the operation amount calculated by the operation amount calculation unit 43a.

  In S420, the bucket tip speed calculation unit 43e is based on the operating speed of each of the hydraulic cylinders 5, 6, and 7 calculated by the cylinder speed calculation unit 43d and the attitude of the work implement 1A calculated by the attitude calculation unit 43b. Then, the speed vector B of the bucket tip (toe) by the operator operation is calculated.

  In S430, the bucket tip speed calculator 43e calculates the control target from the bucket tip based on the distance (coordinates) of the toe of the bucket 10 calculated by the posture calculator 43b and the straight line including the target surface 60 stored in the ROM 93. A distance D (see FIG. 5) to the target surface 60 is calculated. Based on the distance D and the graph of FIG. 8, the limit value ay of the component perpendicular to the target surface 60 of the velocity vector at the bucket tip is calculated.

  In S440, the bucket tip speed calculation unit 43e acquires a component by perpendicular to the target plane 60 in the bucket tip speed vector B calculated by the operator in S420.

  In S450, the target bucket tip speed calculator 43f determines whether or not the limit value ay calculated in S430 is 0 or more. Note that xy coordinates are set as shown in the upper right of FIG. In the xy coordinates, the x axis is parallel to the target surface 60 and the right direction in the drawing is positive, and the y axis is perpendicular to the target surface 60 and the upward direction in the drawing is positive. In the legend in FIG. 16, the vertical component by and the limit value ay are negative, and the horizontal component bx, the horizontal component cx, and the vertical component cy are positive. As is apparent from FIG. 8, when the limit value ay is 0, the distance D is 0, that is, when the toe is located on the target surface 60, and when the limit value ay is positive, the distance D is negative. That is, the toe is located below the target surface 60, and when the limit value ay is negative, the distance D is positive, that is, the toe is located above the target surface 60. When it is determined in S450 that the limit value ay is 0 or more (that is, when the toe is located on or below the target surface 60), the process proceeds to S460, and when the limit value ay is less than 0, the process proceeds to S480.

  In S460, the target bucket tip speed calculator 43f determines whether or not the vertical component by of the toe speed vector B by the operator operation is 0 or more. When by is positive, it indicates that the vertical component by of the velocity vector B is upward, and when by is negative, it indicates that the vertical component by of the velocity vector B is downward. If it is determined in S460 that the vertical component by is 0 or more (that is, if the vertical component by is upward), the process proceeds to S470, and if the vertical component by is less than 0, the process proceeds to S500.

  In S470, the target bucket tip speed calculator 43f compares the limit value ay with the absolute value of the vertical component by, and proceeds to S500 if the absolute value of the limit value ay is greater than or equal to the absolute value of the vertical component by. On the other hand, if the absolute value of the limit value ay is less than the absolute value of the vertical component by, the process proceeds to S530.

  In S500, the target bucket tip speed calculation unit 43f calculates “cy = ay−by” as an expression for calculating a component cy perpendicular to the target surface 60 of the speed vector C of the bucket tip to be generated by the operation of the boom 8 by machine control. And the vertical component cy is calculated based on the equation, the limit value ay in S430, and the vertical component by in S440. Then, a velocity vector C capable of outputting the calculated vertical component cy is calculated, and the horizontal component is set as cx (S510).

  In S520, a target speed vector T is calculated. If the component perpendicular to the target plane 60 of the target velocity vector T is ty and the horizontal component tx, it can be expressed as “ty = by + cy, tx = bx + cx”, respectively. If the formula of S500 (cy = ay−by) is substituted for this, the target speed vector T is eventually “ty = ay, tx = bx + cx”. In other words, the vertical component ty of the target speed vector in S520 is limited to the limit value ay, and forced boom raising by the machine control is activated.

  In S480, the target bucket tip speed calculator 43f determines whether or not the vertical component by of the toe speed vector B by the operator operation is 0 or more. When it is determined in S480 that the vertical component by is 0 or more (that is, when the vertical component by is upward), the process proceeds to S530, and when the vertical component by is less than 0, the process proceeds to S490.

  In S490, the target bucket tip speed calculator 43f compares the limit value ay with the absolute value of the vertical component by, and proceeds to S530 if the absolute value of the limit value ay is greater than or equal to the absolute value of the vertical component by. On the other hand, if the absolute value of the limit value ay is less than the absolute value of the vertical component by, the process proceeds to S500.

  When S530 is reached, there is no need to operate the boom 8 by machine control, so the target bucket tip speed calculator 43f sets the speed vector C to zero. In this case, the target speed vector T becomes “ty = by, tx = bx” based on the formula (ty = by + cy, tx = bx + cx) used in S520, and matches the speed vector B by the operator operation (S540).

  In S550, the target cylinder speed calculation unit 43g calculates the target speed of each hydraulic cylinder 5, 6, 7 based on the target speed vector T (ty, tx) determined in S520 or S540.

  In S560, the target pilot pressure calculation unit 43h sets target pilots to the flow control valves 15a, 15b, 15c of the hydraulic cylinders 5, 6, 7 based on the target speeds of the cylinders 5, 6, 7 calculated in S550. Calculate the pressure.

  In S590, the target pilot pressure calculation unit 43h outputs the target pilot pressure to the flow control valves 15a, 15b, and 15c of the hydraulic cylinders 5, 6, and 7 to the electromagnetic valve control unit 44. The electromagnetic valve control unit 44 controls the electromagnetic proportional valves 54, 55, and 56 so that the target pilot pressure acts on the flow control valves 15a, 15b, and 15c of the hydraulic cylinders 5, 6, and 7, and thereby the work machine 1A. Drilling is performed. When the processing of S590 is completed, the process waits until a lever operation by the operator is detected by the operation amount calculation unit 43a.

  In the above configuration, when machine control is performed by the region restriction control unit 43, the operation devices 45a, 45b, and 46a send the first control signal corresponding to the operation of the operator to at least one of the plurality of flow control valves 15a, 15b, and 15c. Output. The target pilot pressure calculation unit 43h (control signal calculation unit) of the controller 40 (control device) allows the bucket 10 to be positioned on or above the target surface 60 while the operation devices 45a, 45b, and 46a are being operated. A second control signal for operating at least one of the plurality of hydraulic actuators 5, 6, 7 is calculated. Then, the control controller 40 (control device) controls the flow rate control valve for which the second control signal is calculated among the plurality of flow rate control valves 15a, 15b, and 15c based on the second control signal. For the flow rate control valve for which is not calculated, machine control is activated by controlling based on the first control signal, and the work implement 1A is operated so that the bucket 10 is positioned on or above the target surface 60. An example of horizontal excavation operation by machine control in the flowchart of FIG. 16 is shown in FIG. For example, when the operator operates the operating device 45b to perform horizontal excavation by pulling the arm 9 in the direction of arrow A, the electromagnetic proportional valve 54c controls so that the tip of the bucket 10 does not enter the target surface 60. Then, the raising operation of the boom 8 is automatically performed.

  In addition, although the example in the case of performing forced boom raising was given in the flowchart of FIG. 16, control for decelerating the speed of the arm 9 as necessary may be added to machine control in order to improve excavation accuracy. In addition, control is performed so that the bucket 10 automatically rotates in the direction of arrow C by controlling the electromagnetic proportional valve 56d so that the angle B with respect to the target surface 60 of the bucket 10 becomes a constant value and the leveling operation becomes easy. Also good.

<Action and effect>
(1) In the above embodiment, the working machine 1A having the boom 8, the arm 9, and the bucket (working tool) 10, the plurality of hydraulic actuators 5, 6, and 7 that drive the working machine 1A, and the operation of the operator While the operating devices 45a, 45b, and 46a for instructing the operation of the work machine 1A and the operating devices 45a, 45b, and 46a are being operated, the bucket 10 is positioned on or above the arbitrarily set target surface 60. Thus, in the hydraulic excavator 1 including the controller 40 having the region restriction control unit 43 that controls at least one of the plurality of hydraulic actuators 5, 6, 7, the region restriction control unit 43 is provided on the operation lever 1 a. Machine control state change request switch 17 (first switch) that can switch between enabling and disabling control (ie machine control) by And a sound output device that generates a sound at a timing when the machine control state change request switch 17 switches the valid / invalid state of the control of the plurality of flow control valves 15a, 15b, 15c based on the second control signal by the controller 40 53B.

  An operator who is working often looks at the front work machine 1A, particularly the bucket 10 among them, and does not often see the display device 53A. Therefore, when the machine control state is displayed only on the display device 53A, it is not easy for the operator who is working to accurately grasp the machine control state. However, by notifying the operator that the machine control state has been changed via the audio output device 53B with the above configuration, the operator can indicate that the machine control state has been changed by operating his / her switch 17. This can be confirmed without visually recognizing the device 53A. Therefore, the operator can continue the work without removing the line of sight from the front work machine 1A, and further improvement in work efficiency can be expected.

  In the above embodiment, since the machine control state change request switch 17 is provided in the operation lever 1a, the switch 17 is unintentionally operated during the operation of the operation lever 1a by the operator. A change in machine control status may occur. Even in that case, the above configuration notifies the operator that the machine control state has been changed via the audio output device 53B, so that the operator can grasp that the machine control state has been changed. It is possible to prevent the front work machine 1A from operating in the controlled state.

  In the above configuration, since the machine control state change request switch 17 is provided on the operation lever 1a, the operator can easily and easily press the switch 17 in an operation where both excavation by machine control and normal excavation are performed. You can quickly select whether machine control is enabled or disabled.

  (2) Further, in the above embodiment, in addition to the configuration of (1) above, further permission and prohibition of control of the plurality of flow control valves 15a, 15b, 15c based on the second control signal by the region restriction control unit 43 is provided. The machine controller changeover switch (second switch) 371 can be alternatively selected, and the control controller 40 permits the control of the plurality of flow control valves 15a, 15b, and 15c by the region restriction control unit 43 to be machine control changeover. When the switch (second switch) 371 is selected, the switch operation of the machine control state change request switch 17 (first switch) is accepted.

  When the machine control changeover switch (second switch) 371 is provided in this way, when the operator determines that machine control is unnecessary, the machine control changeover switch (second switch) 371 is set to the prohibited position (MC-OFF position). If switched, it is possible to prevent the machine control from becoming effective even if the machine control state change request switch 17 (first switch) is accidentally pressed during the work. That is, the operator's intention to enable machine control can be grasped more reliably.

  (3) Further, in the above embodiment, in addition to the configuration of (1) or (2) above, a rotation speed sensor 490 (rotation) for detecting the rotation speed of the engine 18 (prime mover) mounted on the hydraulic excavator 1 Number detector) and an oil temperature sensor 590 (oil temperature detector) for detecting the temperature of the hydraulic oil supplied to the plurality of hydraulic actuators 5, 6, and 7. And at least one of the hydraulic oil temperatures is equal to or higher than a predetermined value (R1, T1), the machine control state change request switch 17 (valid control of the plurality of flow control valves 15a, 15b, 15c by the region restriction control unit 43) The switch operation of the first switch) is accepted.

  When the work machine is configured in this way, the machine control can be enabled only when the vehicle is in a state where the machine control can be appropriately performed. Therefore, the accuracy and responsiveness of the machine control is reduced due to insufficient engine speed or insufficient oil temperature. Can be prevented.

  (4) In the above embodiment, in addition to any one of the configurations (1) to (3), the region restriction control unit 43 can effectively control the plurality of flow control valves 15a, 15b, and 15c. It is further provided with a voice notification selection switch 393 that can select whether or not the voice output device 53B generates sound at the timing when the invalid state is changed by the machine control state change request switch 17 (first switch).

  When the work machine is configured as described above, when the operator feels troublesome that there is an audio notification every time the switch 17 is pressed, the audio notification function can be disabled.

  (5) In the above embodiment, in addition to any one of the configurations (1) to (4), the region restriction control unit 43 controls the plurality of flow control valves 15a, 15b, and 15c. The sound output device 53B generates different sounds depending on whether the control state change request switch 17 (first switch) is switched from invalid to valid or when it is switched from valid to invalid.

  When the work machine is configured in this way, the operator can easily recognize whether the machine control state is switched between valid and invalid.

  In the above embodiment, since the icon 394 that indicates that the machine control state is valid is displayed on the screen of the display device 53A, the operator sees that the machine control state is valid if the display device 53A is viewed. Is easily recognizable.

<Appendix>
The machine control state change request switch 17 can be installed in a place other than that shown in FIG. 10 as long as it is within the reach of the operator during the shovel operation. For example, the rear side of the gripping portion of the other operation lever 1b. Alternatively, it may be provided at the tip of the operation lever 1a (1b) assuming that the operator's thumb is pressed.

  In FIG. 14, steps S04 (engine speed check) and S05 (hydraulic oil temperature check) are included in the flowchart from the viewpoint of ensuring the accuracy of machine control. The function of recognizing the switching timing of the machine control state by 53B is not impaired. If the machine control changeover switch 371 is not in the ON state, the same processing as that in steps S10 and S11 when invalidating the machine control state may be performed instead of step S08.

  The sound output in step SA03 and step SA05 in FIG. 15 is not limited to the above example (intermittent sound / continuous sound), and any sound can be used as long as the sound output in both steps SA03 and SA05 can be distinguished. I do not care.

  The region restriction control unit 43 (target pilot pressure calculation unit 43h) is configured to control at least the hydraulic actuators 5, 6, and 7 so that the bucket 10 is positioned on or above an arbitrarily set target surface 60 during machine control. The target pilot pressure (second control signal) for operating one is calculated, but other predetermined settings (for example, the angle of the bucket 10 when the toe is on the target surface 60 are set to a predetermined value) The target pilot pressure (second control signal) for operating at least one of the hydraulic actuators 5, 6, and 7 may be calculated so that the work implement 1A operates based on .

  Each configuration related to the control controller 40 described above, functions and execution processing of each configuration, etc. are realized by hardware (for example, logic for executing each function is designed by an integrated circuit). Also good. The configuration related to the control controller 40 may be a program (software) that realizes each function related to the configuration of the control controller 40 by being read and executed by an arithmetic processing device (for example, a CPU). Information related to the program can be stored in, for example, a semiconductor memory (flash memory, SSD, etc.), a magnetic storage device (hard disk drive, etc.), a recording medium (magnetic disk, optical disc, etc.), and the like.

  DESCRIPTION OF SYMBOLS 1A ... Front work machine, 8 ... Boom, 9 ... Arm, 10 ... Bucket, 17 ... Machine control state change request switch (first switch), 30 ... Boom angle sensor, 31 ... Arm angle sensor, 32 ... Bucket angle sensor, DESCRIPTION OF SYMBOLS 40 ... Control controller (control apparatus) 43 ... Area | region restriction | limiting control part, 43a ... Operation amount calculating part, 43b ... Attitude calculating part, 43c ... Target surface calculating part, 43d ... Cylinder speed calculating part, 43e ... Bucket tip speed calculating part , 43f ... target bucket tip speed calculation unit, 43g ... target cylinder speed calculation unit, 43h ... target pilot pressure calculation unit (control signal calculation unit), 44 ... solenoid valve control unit, 45 ... operating device (boom, arm), 46 ... operating device (bucket, turning), 47 ... operating device (running), 50 ... work implement attitude detecting device, 51 ... target plane setting device, 52a, 2b ... Operator operation detection device, 53A ... Display device, 53B ... Audio output device, 54, 55, 56 ... Proportional solenoid valve, 371 ... Machine control changeover switch (second switch), 373 ... Control change judgment unit, 374 ... Notification Control unit, 393... Voice notification selection switch (third switch), 490... Rotation speed sensor (rotation speed detector), 590... Oil temperature sensor (oil temperature detector)

Claims (5)

A working machine having a boom, an arm and a work implement;
A plurality of hydraulic actuators for driving the working machine;
An operating device for instructing the operation of the working machine according to an operation of the operator;
While the operation device is being operated, an area restriction control unit that controls at least one of the plurality of hydraulic actuators is provided so that the work tool is positioned on or above an arbitrarily set target surface. In a work machine comprising a control device,
A first switch provided in the operating device and capable of switching between enabling and disabling of control by the region restriction control unit;
A work machine comprising: an audio output device that generates audio at a timing when the validity and invalidity of the control by the area restriction control unit are switched by the first switch. The work machine according to claim 1,
A second switch that can alternatively select permission and prohibition of control by the area restriction control unit;
The control device receives a switch operation of the first switch when permission of control by the region restriction control unit is selected by the second switch. The work machine according to claim 1,
A rotational speed detector for detecting the rotational speed of a prime mover mounted on the work machine;
An oil temperature detector for detecting the temperature of hydraulic oil supplied to the plurality of hydraulic actuators;
The control device receives a switch operation of the first switch that activates the control by the region restriction control unit when at least one of the rotational speed of the prime mover and the temperature of the hydraulic oil is equal to or higher than a predetermined value. Working machine. The work machine according to claim 1,
And a voice notification selection switch capable of selecting whether or not the voice output device generates a sound at a timing when the valid / invalid state of the control by the area restriction control unit is changed by the first switch. Work machine. The work machine according to claim 1,
A work machine, wherein the audio output device generates different sounds depending on whether the control by the area restriction control unit is switched from invalid to valid and when switched from valid to invalid.

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