Excavator, control device for excavator

Abstract

The present invention provides a technology that enables the tip of an excavator attachment to be moved more appropriately along a design surface. An excavator according to an embodiment of the present disclosure includes an attachment AT, an arm cylinder 8, a boom cylinder 7, and a bucket cylinder 9, and is equipped with a plurality of actuators that drive the attachment AT, and a controller 30 that controls the operation of at least one of the boom cylinder 7 and the bucket cylinder 9 in accordance with the operation of the arm cylinder 8, and the controller 30 controls the operation of the arm cylinder 8 so as to correspond to the operation of the boom cylinder 7 or the bucket cylinder 9 when a predetermined condition related to the operation of at least one of the boom cylinder 7 and the bucket cylinder 9 is met.

Description

Technical Field

[0001] The present disclosure relates to a shovel or the like.

Background Art

[0002] For example, a shovel that performs excavation control to move the tip of a bucket along a design surface is known (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the boom or the like needs to operate in accordance with the movement of the arm according to the arm operation by the operator. Therefore, for example, if the operating speed of the boom required to match the movement of the arm corresponding to the operation amount of the arm by the operator exceeds a predefined limit, the tip of the bucket may exceed the design surface.

[0005] Therefore, in view of the above problems, an object is to provide a technique capable of more appropriately moving the tip of an attachment of a shovel along a design surface.

Means for Solving the Problems

[0006] To achieve the above object, in one embodiment of the present disclosure, a lower traveling body, an upper swing body mounted on the lower traveling body for swing, At an attachment attached to the upper swing body, a first actuator that operates according to an operation command by an operator's operation input or an autonomous driving function, and the ​Automatically including a second actuator, and a plurality of actuators for driving the attachment and the upper swing body, in accordance with the operation of the first actuator, the second actuator Cause it to be operation Automatically a control device that operates the tip of the attachment along a target trajectory by controlling the operation, and is provided with The control device operates the tip of the attachment along the target trajectory by controlling the operation of the second actuator in accordance with the operation of the first actuator. When it becomes impossible to synchronize the operation of the second actuator with the operation of the first actuator, or when there is a possibility that synchronization cannot be achieved, the operation of the first actuator is restricted so as to correspond to the operation of the second actuator. An excavator is provided.

[0007] Also, in another embodiment of the present disclosure, a lower traveling body, an upper swing body mounted on the lower traveling body so as to be rotatable, an attachment attached to the upper swing body, a first actuator that operates according to an operation input of an operator or an operation command by an autonomous driving function, and the At a second actuator, and a control device for an excavator including a plurality of actuators for driving the attachment and the upper swing body, Automatically operates the tip of the attachment along a target trajectory by controlling the operation of the second actuator in accordance with the operation of the first actuator, in accordance with the operation of the first actuator, the second actuator Cause it to be operation Automatically and operates the tip of the attachment along the target trajectory by controlling the operation, By controlling the operation of the second actuator in accordance with the operation of the first actuator, when it becomes impossible to synchronize the operation of the second actuator with the operation of the first actuator so that the tip of the attachment moves along the target trajectory, or when there is a possibility that synchronization may become impossible, the operation of the first actuator is restricted so as to correspond to the operation of the second actuator. A control device for an excavator is provided.

Advantages of the Invention

[0008] According to the above-described embodiment, it is possible to provide a technique capable of more appropriately moving the tip of the attachment of the excavator along the design surface.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4A

Figure 4B

Figure 4C

Figure 4D

Figure 5

Figure 6A

Figure 6B

Figure 6C

Figure 7

Figure 8A

Figure 8B

Figure 9

Figure 10

Modes for Carrying Out the Invention

[0010] Hereinafter, modes for carrying out the invention will be described with reference to the drawings.

[0011] [Outline of Excavator] First, with reference to FIGS. 1 and 2, the outline of the excavator 100 according to the present embodiment will be described.

[0012] FIGS. 1 and 2 are respectively a top view and a side view of the excavator 100 according to the present embodiment.

[0013] The excavator 100 according to the present embodiment includes a lower traveling body 1, an upper swing body 3 mounted on the lower traveling body 1 so as to be swingable via a swing mechanism 2, a boom 4, an arm 5, and a bucket 6 that constitute an attachment AT, and a cabin 10.

[0014] The lower traveling body 1 includes a pair of left and right crawlers 1C, specifically, a left crawler 1CL and a right crawler 1CR, as described below. The lower traveling body 1 drives the left crawler 1CL and the right crawler 1CR hydraulically with traveling hydraulic motors 2M (2ML, 2MR) respectively to move the excavator 100.

[0015] The upper slewing body 3 is driven by a slewing hydraulic motor 2A (an example of a slewing actuator) to slew with respect to the lower traveling body 1.

[0016] The boom 4 is pivotally attached to the center of the front part of the upper slewing body 3 so as to be able to pitch. At the tip of the boom 4, an arm 5 is pivotally attached so as to be able to rotate up and down. At the tip of the arm 5, a bucket 6 as an end attachment is pivotally attached so as to be able to rotate up and down. The boom 4, the arm 5, and the bucket 6 are each hydraulically driven by a boom cylinder 7, an arm cylinder 8, and a bucket cylinder 9 as hydraulic actuators.

[0017] Note that the bucket 6 is an example of an end attachment. At the tip of the arm 5, other end attachments, for example, a slope bucket, a dredging bucket, a breaker, etc. may be attached instead of the bucket 6 according to the work content, etc.

[0018] The cab 10 is a driver's cab in which an operator rides and is mounted on the left side of the front part of the upper slewing body 3.

[0019] The excavator 100 operates the actuators according to the operation of the operator riding in the cab 10 to drive the operating elements (driven elements) such as the lower traveling body 1, the upper slewing body 3, the boom 4, the arm 5, and the bucket 6.

[0020] Alternatively, instead of or in addition to being configured to be operable by the operator in the cab 10, the excavator 100 may be configured to be remotely operable by an operator of a predetermined external device (e.g., the assistance device 200 or the management device 300 described later). In this case, the excavator 100 transmits, for example, image information (captured image) output by the space recognition device 70 described later to the external device. Also, various information images (e.g., various setting screens, etc.) displayed on the display device D1 of the excavator 100 described later may be similarly displayed on the display device provided in the external device. Thereby, the operator can remotely operate the excavator 100 while, for example, checking the content displayed on the display device provided in the external device. Then, the excavator 100 operates the actuator according to a remote operation signal received from the external device and representing the content of the remote operation, and drives operation elements such as the lower traveling body 1, the upper swing body 3, the boom 4, the arm 5, and the bucket 6. When the excavator 100 is remotely operated, the interior of the cab 10 may be unmanned. Hereinafter, the description will proceed on the premise that the operator's operation includes at least one of the operation on the operation device 26 of the operator in the cab 10 and the remote operation of the operator of the external device.

[0021] Further, the excavator 100 may automatically operate the hydraulic actuator regardless of the content of the operator's operation. Thereby, the excavator 100 realizes a function (hereinafter, "automatic operation function" or "machine control function") of automatically operating at least a part of operation elements such as the lower traveling body 1, the upper swing body 3, the boom 4, the arm 5, and the bucket 6.

[0022] The automatic driving function may include a function (so-called "semi-automatic driving function") that automatically operates operating elements (hydraulic actuators) other than the operating element (hydraulic actuator) of the operation target in response to an operation on the operator's operation device 26 or a remote operation. Further, the automatic driving function may include a function (so-called "fully automatic driving function") that automatically operates at least a part of a plurality of driven elements (hydraulic actuators) on the premise that there is no operation on the operator's operation device 26 or a remote operation. In the excavator 100, when the fully automatic driving function is valid, the inside of the cab 10 may be unmanned. Further, the automatic driving function may include a function ("gesture operation function") that the excavator 100 recognizes the gestures of people such as workers around the excavator 100 and automatically operates at least a part of a plurality of driven elements (hydraulic actuators) according to the content of the recognized gestures. Further, the semi-automatic driving function, the fully automatic driving function, and the gesture operation function may include a mode in which the operation content of the operating element (hydraulic actuator) of the automatic driving target is automatically determined according to a rule defined in advance. Further, the semi-automatic driving function, the fully automatic driving function, and the gesture operation function may include a mode (so-called "autonomous driving function") in which the excavator 100 autonomously makes various determinations and the operation content of the operating element (hydraulic actuator) of the automatic driving target is determined autonomously according to the determination result.

[0023] [Configuration of Excavator] Next, in addition to FIGS. 1 and 2, the configuration of the excavator 100 will be described with reference to FIGS. 3 and 4 (FIGS. 4A to 4D).

[0024] FIG. 3 is a diagram for explaining an example of the configuration of the hydraulic system of the excavator 100 according to the present embodiment. FIGS. 4A to 4D are diagrams showing an example of the configuration parts of the operation system related to the attachment AT and the upper swing body 3 in the hydraulic system of the excavator 100 according to the present embodiment. Specifically, FIGS. 4A to 4D are diagrams showing an example of the configuration parts of the operation system related to the arm 5, the boom 4, the bucket 6, and the upper swing body 3, respectively.

[0025] The hydraulic system of the excavator 100 according to this embodiment includes an engine 11, a regulator 13, a main pump 14, a pilot pump 15, a control valve 17, an operating device 26, a discharge pressure sensor 28, an operating pressure sensor 29, and a controller 30. Also, as described above, the hydraulic system of the excavator 100 according to this embodiment includes hydraulic actuators such as traveling hydraulic motors 2ML, 2MR that hydraulically drive the lower traveling body 1, the upper swing body 3, the boom 4, the arm 5, and the bucket 6, a swing hydraulic motor 2A, a boom cylinder 7, an arm cylinder 8, and a bucket cylinder 9.

[0026] The engine 11 is the main power source of the hydraulic system and is mounted, for example, at the rear of the upper swing body 3. Specifically, the engine 11 rotates at a constant speed at a preset target rotational speed under the direct or indirect control of the controller 30 and drives the main pump 14 and the pilot pump 15. The engine 11 is, for example, a diesel engine that uses light oil as fuel.

[0027] The regulator 13 controls the discharge amount of the main pump 14. For example, the regulator 13 adjusts the angle (tilt angle) of the swash plate of the main pump 14 in response to a control command from the controller 30. The regulator 13 includes regulators 13L, 13R corresponding to the main pumps 14L, 14R described later.

[0028] The main pump 14 is mounted, for example, at the rear of the upper swing body 3, similar to the engine 11, and as described above, is driven by the engine 11 to supply hydraulic oil to the control valve 17 through a high-pressure hydraulic line. The main pump 14 is, for example, a variable displacement hydraulic pump, and under the control of the controller 30, as described above, the stroke length of the piston is adjusted by adjusting the tilt angle of the swash plate by the regulator 13, and the discharge flow rate (discharge pressure) is controlled. The main pump 14 includes main pumps 14L, 14R.

[0029] The pilot pump 15 is mounted, for example, at the rear of the upper swing body 3 and supplies pilot pressure to the operating device 26 via a pilot line. The pilot pump 15 is, for example, a fixed displacement hydraulic pump and is driven by the engine 11 as described above.

[0030] The control valve 17 is mounted, for example, at the center of the upper swing body 3 and is a hydraulic control device that controls the hydraulic drive system according to the operation of the operating device 26 by the operator or remote operation. As described above, the control valve 17 is connected to the main pump 14 via a high-pressure hydraulic line, and the hydraulic oil supplied from the main pump 14 is selectively supplied to hydraulic actuators (travel hydraulic motors 2ML, 2MR, swing hydraulic motor 2A, boom cylinder 7, arm cylinder 8, and bucket cylinder 9) according to the operation of the operating device 26 or the state of remote operation. Specifically, the control valve 17 includes control valves 171 to 176 that control the flow rate and flow direction of the hydraulic oil supplied from the main pump 14 to each of the hydraulic actuators. The control valve 171 corresponds to the travel hydraulic motor 2ML. Also, the control valve 172 corresponds to the travel hydraulic motor 2MR. Also, the control valve 173 corresponds to the swing hydraulic motor 2A, and the control valve 174 corresponds to the bucket cylinder 9. Also, the control valve 175 corresponds to the boom cylinder 7 and includes control valves 175L and 175R. The control valve 176 corresponds to the arm cylinder 8 and includes control valves 176L and 176R.

[0031] The operating device 26 is provided near the driver's seat in the cabin 10 and is an operation input means for the operator to operate various operation elements (lower traveling body 1, upper swing body 3, boom 4, arm 5, bucket 6, etc.). In other words, the operating device 26 is an operation input means for the operator to operate the hydraulic actuators (i.e., travel hydraulic motors 2ML, 2MR, swing hydraulic motor 2A, boom cylinder 7, arm cylinder 8, bucket cylinder 9, etc.) that drive the respective operation elements.

[0032] As shown in FIGS. 3, 4A to 4D, the operating device 26 is a hydraulic pilot type. The operating device 26 is connected to the control valve 17 directly through its secondary pilot line or via a shuttle valve 32 (described later) provided in the secondary pilot line. Thereby, pilot pressure corresponding to the operating states of the lower traveling body 1, upper slewing body 3, boom 4, arm 5, bucket 6, etc. in the operating device 26 can be input to the control valve 17. Therefore, the control valve 17 can drive each hydraulic actuator according to the operating state in the operating device 26. The operating device 26 includes an attachment AT, that is, a boom 4 (boom cylinder 7), an arm 5 (arm cylinder 8), a bucket 6 (bucket cylinder 9), and a left operating lever 26L and a right operating lever 26R for operating the upper slewing body 3. Further, the operating device 26 includes a traveling lever 26D for operating the lower traveling body 1, and the traveling lever 26D includes a left traveling lever 26DL for operating the left crawler 1CL and a right traveling lever 26DR for operating the right crawler 1CR.

[0033] The left operating lever 26L is used for the slewing operation of the upper slewing body 3 and the operation of the arm 5. When the left operating lever 26L is operated in the front-rear direction (i.e., the front-rear direction of the upper slewing body 3) as viewed from the operator in the cab 10, it uses the hydraulic oil discharged from the pilot pump 15 and outputs a control pressure (pilot pressure) corresponding to the lever operation amount to the secondary pilot line. Also, when the left operating lever 26L is operated in the left-right direction (i.e., the left-right direction of the upper slewing body 3) as viewed from the operator in the cab 10, it uses the hydraulic oil discharged from the pilot pump 15 and outputs a control pressure (pilot pressure) corresponding to the lever operation amount to the secondary pilot line.

[0034] The right operation lever 26R is used for the operation of the boom 4 and the bucket 6. When the right operation lever 26R is operated in the front-rear direction as viewed by the operator in the cab 10, it utilizes the hydraulic oil discharged from the pilot pump 15 and outputs a control pressure (pilot pressure) corresponding to the lever operation amount to the secondary pilot line. Also, when the right operation lever 26R is operated in the left-right direction, it utilizes the hydraulic oil discharged from the pilot pump 15 and outputs a control pressure (pilot pressure) corresponding to the lever operation amount to the secondary pilot line.

[0035] As described above, the left travel lever 26DL is used for the operation of the left crawler 1CL and may be configured to be interlocked with a left travel pedal (not shown). When the left travel lever 26DL is operated in the front-rear direction as viewed by the operator in the cab 10, it utilizes the hydraulic oil discharged from the pilot pump 15 and outputs a control pressure (pilot pressure) corresponding to the lever operation amount to the secondary pilot line. The secondary pilot lines corresponding to the forward and reverse operations of the left travel lever 26DL are directly connected to the corresponding pilot ports of the control valve 171, respectively. That is, the operation content of the left travel lever 26DL is reflected in the spool position of the control valve 171 that drives the travel hydraulic motor 2ML.

[0036] As described above, the right travel lever 26DR is used for the operation of the right crawler 1CR and may be configured to be interlocked with a right travel pedal (not shown). When the right travel lever 26DR is operated in the front-rear direction as viewed by the operator in the cab 10, it utilizes the hydraulic oil discharged from the pilot pump 15 and outputs a control pressure (pilot pressure) corresponding to the lever operation amount to the secondary pilot line. The secondary pilot lines corresponding to the forward and reverse operations of the right travel lever 26DR are directly connected to the corresponding pilot ports of the control valve 172, respectively. That is, the operation content of the left travel lever 26DL is reflected in the spool position of the control valve 172 that drives the travel hydraulic motor 2ML.

[0037] Further, the operation device 26 (left operation lever 26L, right operation lever 26R, left travel lever 26DL, and right travel lever 26DR) may be an electric type that outputs an electric signal (hereinafter, "operation signal") instead of a hydraulic pilot type that outputs pilot pressure. In this case, the electric signal (operation signal) from the operation device 26 is input to the controller 30, and the controller 30 controls each control valve 171-176 in the control valve 17 according to the input electric signal, thereby realizing the operations of various hydraulic actuators according to the operation content of the operation device 26. For example, the control valves 171-176 in the control valve 17 may be electromagnetic solenoid type spool valves driven by commands from the controller 30. Also, for example, a hydraulic control valve (hereinafter, "operation control valve") that operates according to an electric signal from the controller 30 may be arranged between the pilot pump 15 and the pilot ports of the control valves 171-176. The operation control valve may be, for example, the proportional valve 31, and the shuttle valve 32 is omitted. In this case, when a manual operation using the electric operation device 26 is performed, the controller 30 controls the operation control valve with an electric signal corresponding to the operation amount (e.g., lever operation amount) to increase or decrease the pilot pressure, so that each control valve 171-176 can be operated according to the operation content of the operation device 26. Hereinafter, the description will proceed on the premise that the operation control valve is the proportional valve 31.

[0038] The discharge pressure sensor 28 detects the discharge pressure of the main pump 14. The detection signal corresponding to the discharge pressure detected by the discharge pressure sensor 28 is taken into the controller 30. The discharge pressure sensor 28 includes discharge pressure sensors 28L and 28R that detect the discharge pressures of the main pumps 14L and 14R, respectively.

[0039] The operation pressure sensor 29 detects the pilot pressure on the secondary side of the operation device 26, that is, the pilot pressure corresponding to the operation state of each operation element (i.e., hydraulic actuator) in the operation device 26. The detection signal of the pilot pressure corresponding to the operation states of the lower traveling body 1, upper swing body 3, boom 4, arm 5, bucket 6, etc. in the operation device 26 by the operation pressure sensor 29 is taken into the controller 30. The operation pressure sensor 29 includes operation pressure sensors 29LA, 29LB, 29RA, 29RB, 29DL, and 29DR.

[0040] The operation pressure sensor 29LA detects the operation content in the front-rear direction (e.g., operation direction and operation amount) with respect to the left operation lever 26L by the operator in the form of the pressure of the hydraulic oil (hereinafter, "operation pressure") in the pilot line on the secondary side of the left operation lever 26L.

[0041] The operation pressure sensor 29LB detects the operation content in the left-right direction (e.g., operation direction and operation amount) with respect to the left operation lever 26L by the operator in the form of the operation pressure in the pilot line on the secondary side of the left operation lever 26L.

[0042] The operation pressure sensor 29RA detects the operation content in the front-rear direction (e.g., operation direction and operation amount) with respect to the right operation lever 26R by the operator in the form of the operation pressure in the pilot line on the secondary side of the right operation lever 26R.

[0043] The operation pressure sensor 29RB detects the operation content in the left-right direction (e.g., operation direction and operation amount) with respect to the right operation lever 26R by the operator in the form of the operation pressure in the pilot line on the secondary side of the right operation lever 26R.

[0044] The operation pressure sensor 29DL detects the operation content in the front-rear direction (e.g., operation direction and operation amount) with respect to the left travel lever 26DL by the operator in the form of the operation pressure in the pilot line on the secondary side of the left travel lever 26DL.

[0045] The operation pressure sensor 29DR detects the content of the operator's forward and backward operation on the right travel lever 26DR (for example, the operation direction and operation amount) in the form of the operation pressure of the pilot line on the secondary side of the right travel lever 26DR.

[0046] In addition, the operation content of the operating device 26 (left operation lever 26L, right operation lever 26R, left travel lever 26DL, and right travel lever 26DR) may be detected by sensors other than the operation pressure sensor 29 (for example, potentiometers attached to the right operation lever 26R, left travel lever 26DL, and right travel lever 26DR, etc.).

[0047] The controller 30 is provided, for example, inside the cab 10 and controls the driving of the excavator 100. The functions of the controller 30 may be realized by any hardware, software, or a combination thereof. For example, the controller 30 is mainly composed of a microcomputer including a memory device such as a CPU (Central Processing Unit) and RAM (Random Access Memory) (also referred to as the "main memory device"), a non-volatile auxiliary storage device such as a ROM (Read Only Memory), and various input / output interface devices. The controller 30 realizes various functions by executing various programs installed in the non-volatile auxiliary storage device on the CPU.

[0048] In addition, a part of the functions of the controller 30 may be realized by other controllers (control devices). That is, the functions of the controller 30 may be realized in a manner distributed among a plurality of controllers.

[0049] Here, as shown in FIG. 3, in the hydraulic system of the excavator 100, the part of the hydraulic system of the drive system that drives the hydraulic actuator circulates the hydraulic oil from each of the main pumps 14L and 14R driven by the engine 11 through the center bypass oil passages 40L and 40R and the parallel oil passages 42L and 42R to the hydraulic oil tank.

[0050] The center bypass oil passage 40L starts from the main pump 14L, passes through the control valves 171, 173, 175L, and 176L arranged in the control valve 17 in sequence, and reaches the hydraulic oil tank.

[0051] The center bypass oil passage 40R starts from the main pump 14R, passes through the control valves 172, 174, 175R, and 176R arranged in the control valve 17 in sequence, and reaches the hydraulic oil tank.

[0052] The control valve 171 is a spool valve that supplies the hydraulic oil discharged from the main pump 14L to the travel hydraulic motor 2ML, and discharges the hydraulic oil discharged from the travel hydraulic motor 2ML to the hydraulic oil tank.

[0053] The control valve 172 is a spool valve that supplies the hydraulic oil discharged from the main pump 14R to the travel hydraulic motor 2MR, and discharges the hydraulic oil discharged from the travel hydraulic motor 2MR to the hydraulic oil tank.

[0054] The control valve 173 is a spool valve that supplies the hydraulic oil discharged from the main pump 14L to the swing hydraulic motor 2A, and discharges the hydraulic oil discharged from the swing hydraulic motor 2A to the hydraulic oil tank.

[0055] The control valve 174 is a spool valve that supplies the hydraulic oil discharged from the main pump 14R to the bucket cylinder 9, and discharges the hydraulic oil in the bucket cylinder 9 to the hydraulic oil tank.

[0056] The control valves 175L and 175R are spool valves that supply the hydraulic oil discharged from the main pumps 14L and 14R to the boom cylinder 7 respectively, and discharge the hydraulic oil in the boom cylinder 7 to the hydraulic oil tank.

[0057] The control valves 176L and 176R are spool valves that supply the hydraulic oil discharged from the main pumps 14L and 14R to the arm cylinder 8 respectively, and discharge the hydraulic oil in the arm cylinder 8 to the hydraulic oil tank.

[0058] The control valves 171, 172, 173, 174, 175L, 175R, 176L, and 176R adjust the flow rate of the hydraulic oil supplied to and discharged from the hydraulic actuator or switch the flow direction according to the pilot pressure acting on the pilot port, respectively.

[0059] The parallel oil passage 42L supplies the hydraulic oil of the main pump 14L to the control valves 171, 173, 175L, and 176L in parallel with the center bypass oil passage 40L. Specifically, the parallel oil passage 42L branches from the center bypass oil passage 40L upstream of the control valve 171 and is configured to be able to supply the hydraulic oil of the main pump 14L in parallel to each of the control valves 171, 173, 175L, and 176R. Thereby, when the flow of the hydraulic oil passing through the center bypass oil passage 40L is restricted or blocked by any of the control valves 171, 173, and 175L, the parallel oil passage 42L can supply the hydraulic oil to the more downstream control valve.

[0060] The parallel oil passage 42R supplies the hydraulic oil of the main pump 14R to the control valves 172, 174, 175R, and 176R in parallel with the center bypass oil passage 40R. Specifically, the parallel oil passage 42R branches from the center bypass oil passage 40R upstream of the control valve 172 and is configured to be able to supply the hydraulic oil of the main pump 14R in parallel to each of the control valves 172, 174, 175R, and 176R. The parallel oil passage 42R can supply the hydraulic oil to the more downstream control valve when the flow of the hydraulic oil passing through the center bypass oil passage 40R is restricted or blocked by any of the control valves 172, 174, and 175R.

[0061] The regulators 13L and 13R adjust the discharge amounts of the main pumps 14L and 14R by adjusting the tilting angles of the swash plates of the main pumps 14L and 14R under the control of the controller 30, respectively.

[0062] The discharge pressure sensor 28L detects the discharge pressure of the main pump 14L, and the detection signal corresponding to the detected discharge pressure is taken into the controller 30. The same applies to the discharge pressure sensor 28R. Thereby, the controller 30 can control the regulators 13L and 13R according to the discharge pressures of the main pumps 14L and 14R.

[0063] In the center bypass oil passages 40L and 40R, negative control throttles (hereinafter referred to as "negative control throttles") 18L and 18R are provided between the most downstream control valves 176L and 176R and the hydraulic oil tank respectively. Thereby, the flow of the hydraulic oil discharged by the main pumps 14L and 14R is restricted by the negative control throttles 18L and 18R. And the negative control throttles 18L and 18R generate a control pressure (hereinafter referred to as "negative control pressure") for controlling the regulators 13L and 13R.

[0064] The negative control pressure sensors 19L and 19R detect the negative control pressure, and the detection signal corresponding to the detected negative control pressure is taken into the controller 30.

[0065] The controller 30 can control the regulators 13L and 13R according to the discharge pressures of the main pumps 14L and 14R detected by the discharge pressure sensors 28L and 28R, and adjust the discharge amounts of the main pumps 14L and 14R. For example, the controller 30 can control the regulator 13L according to the increase in the discharge pressure of the main pump 14L, and reduce the discharge amount by adjusting the swash plate tilt angle of the main pump 14L. The same applies to the regulator 13R. Thereby, the controller 30 can perform the total horsepower control of the main pumps 14L and 14R so that the absorbed horsepower of the main pumps 14L and 14R, which is represented by the product of the discharge pressure and the discharge amount, does not exceed the output horsepower of the engine 11.

[0066] Further, the controller 30 may adjust the discharge amounts of the main pumps 14L and 14R by controlling the regulators 13L and 13R according to the negative pressure detected by the negative pressure sensors 19L and 19R. For example, the controller 30 decreases the discharge amounts of the main pumps 14L and 14R as the negative pressure increases, and increases the discharge amounts of the main pumps 14L and 14R as the negative pressure decreases.

[0067] Specifically, in the standby state (the state shown in FIG. 3) where none of the hydraulic actuators in the excavator 100 are operated, the hydraulic oil discharged from the main pumps 14L and 14R reaches the negative pressure throttles 18L and 18R through the center bypass oil passages 40L and 40R. Then, the flow of the hydraulic oil discharged from the main pumps 14L and 14R increases the negative pressure generated upstream of the negative pressure throttles 18L and 18R. As a result, the controller 30 decreases the discharge amounts of the main pumps 14L and 14R to the allowable minimum discharge amount, and suppresses the pressure loss (pumping loss) when the discharged hydraulic oil passes through the center bypass oil passages 40L and 40R.

[0068] On the other hand, when any of the hydraulic actuators is operated through the operating device 26, the hydraulic oil discharged from the main pumps 14L and 14R flows into the hydraulic actuator to be operated through the control valve corresponding to the hydraulic actuator to be operated. Then, the flow of the hydraulic oil discharged from the main pumps 14L and 14R decreases or eliminates the amount reaching the negative pressure throttles 18L and 18R, and decreases the negative pressure generated upstream of the negative pressure throttles 18L and 18R. As a result, the controller 30 increases the discharge amounts of the main pumps 14L and 14R, circulates sufficient hydraulic oil to the hydraulic actuator to be operated, and can surely drive the hydraulic actuator to be operated.

[0069] Also, as shown in FIGS. 3, 4A to 4D, in the hydraulic system of the excavator 100, the hydraulic system part related to the operation system includes a pilot pump 15, an operation device 26 (left operation lever 26L, right operation lever 26R, left travel lever 26DL, and right travel lever 26DR), a proportional valve 31, a shuttle valve 32, and a proportional valve 33 for pressure reduction.

[0070] The proportional valve 31 is provided in a pilot line connecting the pilot pump 15 and the shuttle valve 32, and is configured to be able to change its flow passage area (the cross-sectional area through which the hydraulic oil can flow). The proportional valve 31 operates in response to a control command input from the controller 30. Thereby, even when the operation device 26 (specifically, the left operation lever 26L and the right operation lever 26R) is not operated by the operator, the controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the pilot ports of the corresponding control valves (specifically, control valves 173 to 176) in the control valve 17 via the proportional valve 31 and the shuttle valve 32. Therefore, the controller 30 can realize the automatic operation function and the remote operation function of the excavator 100 by controlling the proportional valve 31. The proportional valve 31 includes proportional valves 31AL, 31AR, 31BL, 31BR, 31CL, 31CR, 31DL, and 31DR.

[0071] The shuttle valve 32 has two inlet ports and one outlet port, and outputs the hydraulic oil having the higher pilot pressure among the pilot pressures input to the two inlet ports to the outlet port. One of the two inlet ports of the shuttle valve 32 is connected to the operating device 26, and the other is connected to the proportional valve 31. The outlet port of the shuttle valve 32 is connected to the pilot port of the corresponding control valve in the control valve 17 through a pilot line. Therefore, the shuttle valve 32 can apply the higher one of the pilot pressure generated by the operating device 26 and the pilot pressure generated by the proportional valve 31 to the pilot port of the corresponding control valve. That is, the controller 30 can control the corresponding control valve and control the operations of the lower traveling body 1, the upper swing body 3, and the attachment AT without depending on the operation of the operating device 26 by the operator by causing the proportional valve 31 to output a pilot pressure higher than the secondary pilot pressure output from the operating device 26. The shuttle valve 32 includes shuttle valves 32AL, 32AR, 32BL, 32BR, 32CL, 32CR, 32DL, and 32DR.

[0072] The pressure-reducing proportional valve 33 is provided in a pilot line connecting the operating device 26 and the shuttle valve 32. The pressure-reducing proportional valve 33 is configured, for example, to be able to change its flow passage area. The pressure-reducing proportional valve 33 operates in response to a control command input from the controller 30. Thereby, when the operating device 26 (specifically, the lever devices 26A to 26C) is operated by the operator, the controller 30 can forcibly reduce the pilot pressure output from the operating device 26. Therefore, even when the operating device 26 is being operated, the controller 30 can forcibly suppress or stop the operation of the hydraulic actuator corresponding to the operation of the operating device 26. Further, the controller 30 can, for example, reduce the pilot pressure output from the operating device 26 and make it lower than the pilot pressure output from the proportional valve 31 even when the operating device 26 is being operated. Therefore, by controlling the proportional valve 31 and the pressure-reducing proportional valve 33, the controller 30 can surely cause a desired pilot pressure to act on the pilot port of the control valve in the control valve 17, for example, regardless of the operation content of the operating device 26. Thus, the controller 30 can more appropriately realize the automatic operation function and the remote operation function of the excavator 100, for example, by controlling the pressure-reducing proportional valve 33 in addition to the proportional valve 31. The pressure-reducing proportional valve 33 includes pressure-reducing proportional valves 33AL, 33AR, 33BL, 33BR, 33CL, 33CR, 33DL, and 33DR, as will be described later.

[0073] Further, the pressure-reducing proportional valve 33 may be replaced with a switching valve. The switching valve switches, under the control of the controller 30, between a communicating state and a non-communicating state of the pilot line between the operating device 26 and the shuttle valve 32 (32AL, 32AR).

[0074] As shown in FIG. 4A, the left operation lever 26L is used to operate the arm cylinder 8 corresponding to the arm 5 in a manner that the operator tilts in the front-rear direction. That is, when the left operation lever 26L is tilted in the front-rear direction, the operation of the arm 5 is the operation target. The left operation lever 26L utilizes the hydraulic oil discharged from the pilot pump 15 and outputs a pilot pressure corresponding to the operation content in the front-rear direction to the secondary side.

[0075] The shuttle valve 32AL has two inlet ports respectively connected to the secondary pilot line of the left operation lever 26L corresponding to the closing operation of the arm 5 (hereinafter, "arm closing operation") and the secondary pilot line of the proportional valve 31AL, and the outlet port is connected to the right pilot port of the control valve 176L and the left pilot port of the control valve 176R.

[0076] The shuttle valve 32AR has two inlet ports respectively connected to the secondary pilot line of the left operation lever 26L corresponding to the opening operation of the arm 5 (hereinafter, "arm opening operation") and the secondary pilot line of the proportional valve 31AR, and the outlet port is connected to the left pilot port of the control valve 176L and the right pilot port of the control valve 176R.

[0077] That is, the left operation lever 26L causes a pilot pressure corresponding to the operation content in the front-rear direction to act on the pilot ports of the control valves 176L and 176R via the shuttle valves 32AL and 32AR. Specifically, when the arm closing operation is performed, the left operation lever 26L outputs a pilot pressure corresponding to the operation amount to one inlet port of the shuttle valve 32AL, and causes it to act on the right pilot port of the control valve 176L and the left pilot port of the control valve 176R via the shuttle valve 32AL. Also, when the arm opening operation is performed, the left operation lever 26L outputs a pilot pressure corresponding to the operation amount to one inlet port of the shuttle valve 32AR, and causes it to act on the left pilot port of the control valve 176L and the right pilot port of the control valve 176R via the shuttle valve 32AR.

[0078] The proportional valve 31AL operates according to the control current input from the controller 30. Specifically, the proportional valve 31AL uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other pilot port of the shuttle valve 32AL. Thereby, the proportional valve 31AL can adjust the pilot pressure acting on the right pilot port of the control valve 176L and the left pilot port of the control valve 176R via the shuttle valve 32AL.

[0079] The proportional valve 31AR operates according to the control current input from the controller 30. Specifically, the proportional valve 31AR uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other pilot port of the shuttle valve 32AR. Thereby, the proportional valve 31AR can adjust the pilot pressure acting on the left pilot port of the control valve 176L and the right pilot port of the control valve 176R via the shuttle valve 32AR.

[0080] That is, the proportional valves 31AL and 31AR can adjust the pilot pressure output to the secondary side so that the control valves 176L and 176R can be stopped at an arbitrary valve position regardless of the operation state of the left operation lever 26L.

[0081] The proportional valve 33AL for pressure reduction operates according to the control current input from the controller 30. Specifically, when no control current is input from the controller 30, the proportional valve 33AL for pressure reduction directly outputs the pilot pressure corresponding to the arm closing operation of the left operation lever 26L to the secondary side. On the other hand, when the control current is input from the controller 30, the proportional valve 33AL for pressure reduction reduces the pilot pressure of the pilot line on the secondary side corresponding to the arm closing operation of the left operation lever 26L to an extent according to the control current, and outputs the reduced pilot pressure to one inlet port of the shuttle valve 32AL. Thereby, even when the arm closing operation is being performed with the left operation lever 26L, the proportional valve 33AL for pressure reduction can forcibly suppress or stop the operation of the arm cylinder 8 corresponding to the arm closing operation as needed. Also, even when the arm closing operation is being performed with the left operation lever 26L, the proportional valve 33AL for pressure reduction can make the pilot pressure acting on one inlet port of the shuttle valve 32AL lower than the pilot pressure acting on the other inlet port of the shuttle valve 32AL from the proportional valve 31AL. Therefore, the controller 30 can control the proportional valve 31AL and the proportional valve 33AL for pressure reduction to surely act a desired pilot pressure on the pilot ports on the arm closing sides of the control valves 176L, 176R.

[0082] The proportional valve 33AR for pressure reduction operates according to the control current input from the controller 30. Specifically, when no control current is input from the controller 30, the proportional valve 33AR for pressure reduction directly outputs the pilot pressure corresponding to the arm opening operation of the left operation lever 26L to the secondary side. On the other hand, when the control current from the controller 30 is input, the proportional valve 33AR for pressure reduction reduces the pilot pressure of the pilot line on the secondary side corresponding to the arm opening operation of the left operation lever 26L to an extent according to the control current, and outputs the reduced pilot pressure to one inlet port of the shuttle valve 32AR. Thereby, even when the arm opening operation is being performed by the left operation lever 26L, the proportional valve 33AR for pressure reduction can forcibly suppress or stop the operation of the arm cylinder 8 corresponding to the arm opening operation as necessary. Also, even when the arm opening operation is being performed by the left operation lever 26L, the proportional valve 33AR for pressure reduction can make the pilot pressure acting on one inlet port of the shuttle valve 32AR lower than the pilot pressure acting on the other inlet port of the shuttle valve 32AR from the proportional valve 31AR. Therefore, the controller 30 can control the proportional valve 31AR and the proportional valve 33AR for pressure reduction to surely act a desired pilot pressure on the pilot ports on the arm opening sides of the control valves 176L and 176R.

[0083] In this way, the proportional valves 33AL and 33AR for pressure reduction can forcibly suppress or stop the operation of the arm cylinder 8 corresponding to the operation state of the left operation lever 26L in the front-rear direction. Also, the proportional valves 33AL and 33AR for pressure reduction can reduce the pilot pressure acting on one inlet port of the shuttle valves 32AL and 32AR, and assist to ensure that the pilot pressure of the proportional valves 31AL and 31AR acts on the pilot ports of the control valves 176L and 176R through the shuttle valves 32AL and 32AR.

[0084] Further, instead of controlling the pressure reducing proportional valve 33AL, the controller 30 may forcibly suppress or stop the operation of the arm cylinder 8 corresponding to the arm closing operation of the left operation lever 26L by controlling the proportional valve 31AR. For example, when the arm closing operation is performed with the left operation lever 26L, the controller 30 controls the proportional valve 31AR, and a predetermined pilot pressure is applied to the pilot ports on the arm opening side of the control valves 176L and 176R via the shuttle valve 32AR from the proportional valve 31AR. Thereby, the pilot pressure acts on the pilot ports on the arm opening side of the control valves 176L and 176R in a manner that counteracts the pilot pressure acting on the pilot ports on the arm closing side of the control valves 176L and 176R via the shuttle valve 32AL from the left operation lever 26L. Therefore, the controller 30 can forcibly move the control valves 176L and 176R closer to the neutral position to suppress or stop the operation of the arm cylinder 8 corresponding to the arm closing operation of the left operation lever 26L. Similarly, instead of controlling the pressure reducing proportional valve 33AR, the controller 30 may forcibly suppress or stop the operation of the arm cylinder 8 corresponding to the arm opening operation of the left operation lever 26L by controlling the proportional valve 31AL.

[0085] Also, the pressure reducing proportional valves 33AL and 33AR may each be replaced with a switching valve. The same may apply to the pressure reducing proportional valves 33BL, 33BR, 33CL, 33CR, 33DL, and 33DR hereinafter.

[0086] The switching valve corresponding to the pressure reducing proportional valve 33AL is provided in the pilot line between the secondary port of the left operation lever 26L corresponding to the arm closing operation and the shuttle valve 32AL, and switches the communication / non-communication of the pilot line according to a control command input from the controller 30. For example, the switching valve is normally of the normally open type that maintains the pilot line in a communicating state, and according to a control command from the controller 30, the pilot line is made non-communicating, and the hydraulic oil corresponding to the arm closing operation output from the left operation lever 26L may be discharged to the hydraulic oil tank.

[0087] The switching valve corresponding to the pressure reducing proportional valve 33AR is provided in a pilot line between the secondary port of the left operation lever 26L corresponding to the arm opening operation and the shuttle valve 32AR, and switches the communication / non-communication of the pilot line according to a control command input from the controller 30. For example, the switching valve is normally of a normally open type that maintains the pilot line in a communicating state, and according to a control command from the controller 30, the pilot line can be made non-communicating, and the hydraulic oil corresponding to the arm opening operation output from the left operation lever 26L can be discharged to the hydraulic oil tank.

[0088] That is, the switching valve can prevent the pilot pressure corresponding to the operation of the arm 5 on the left operation lever 26L from being input to the shuttle valves 32AL and 32AR.

[0089] The operation pressure sensor 29LA detects the operation content in the front-rear direction of the left operation lever 26L by the operator in the form of pressure (operation pressure), and the detection signal corresponding to the detected pressure is taken into the controller 30. Thereby, the controller 30 can grasp the operation content in the front-rear direction of the left operation lever 26L. The operation content in the front-rear direction of the left operation lever 26L to be detected may include, for example, the operation direction, the operation amount (operation angle), etc. Hereinafter, the same applies to the operation content in the left-right direction of the left operation lever 26L and the operation content in the front-rear direction and the left-right direction of the right operation lever 26R.

[0090] The controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the pilot port on the right side of the control valve 176L and the pilot port on the left side of the control valve 176R via the proportional valves 31AL and 32AL, regardless of the arm closing operation on the left operation lever 26L by the operator. Also, the controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the pilot port on the left side of the control valve 176L and the pilot port on the right side of the control valve 176R via the proportional valves 31AR and 32AR, regardless of the arm opening operation on the left operation lever 26L by the operator. That is, the controller 30 can automatically control the opening and closing operation of the arm 5 and realize the automatic operation function, remote operation function, etc. of the excavator 100.

[0091] Also, as described above, the controller 30 can control the pressure reducing proportional valves 33AL and 33AR and the switching valves to relatively lower the pilot pressure input from the secondary pilot line of the left operation lever 26L corresponding to the operation of the arm 5 to the shuttle valves 32AL and 32AR. Thereby, the controller 30 can apply a pilot pressure smaller than the pilot pressure corresponding to the operation of the arm 5 on the left operation lever 26L to the corresponding pilot ports of the control valves 176L and 176R via the proportional valves 31AL and 31AR and the shuttle valves 32AL and 32AR. Therefore, for example, the controller 30 can slow down the operating speed, operating acceleration, etc. of the arm 5 with respect to the operation amount regarding the operation of the arm 5 on the left operation lever 26L.

[0092] Also, for example, as shown in FIG. 4B, the right operation lever 26R is used to operate the boom cylinder 7 corresponding to the boom 4 in a manner where the operator tilts in the front-rear direction. That is, when the right operation lever 26R is tilted in the front-rear direction, the operation of the boom 4 is the operation target. The right operation lever 26R outputs a pilot pressure corresponding to the operation content in the front-rear direction to the secondary side using the hydraulic oil discharged from the pilot pump 15.

[0093] The shuttle valve 32BL has two inlet ports respectively connected to the secondary pilot line of the right operation lever 26R corresponding to the upward operation of the boom 4 (hereinafter referred to as "boom upward operation") and the secondary pilot line of the proportional valve 31BL, and the outlet port is connected to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R.

[0094] The shuttle valve 32BR has two inlet ports respectively connected to the secondary pilot line of the right operation lever 26R corresponding to the downward operation of the boom 4 (hereinafter referred to as "boom downward operation") and the secondary pilot line of the proportional valve 31BR, and the outlet port is connected to the right pilot port of the control valve 175R.

[0095] That is, the right operation lever 26R causes the pilot pressure corresponding to the operation content in the front-rear direction to act on the pilot ports of the control valves 175L and 175R via the shuttle valves 32BL and 32BR. Specifically, when the boom is operated upward, the right operation lever 26R outputs a pilot pressure corresponding to the operation amount to one inlet port of the shuttle valve 32BL, and via the shuttle valve 32BL, it acts on the right pilot port of the control valve 175L and the left pilot port of the control valve 175R. Also, when the boom is operated downward, the right operation lever 26R outputs a pilot pressure corresponding to the operation amount to one inlet port of the shuttle valve 32BR, and via the shuttle valve 32BR, it acts on the right pilot port of the control valve 175R.

[0096] The proportional valve 31BL operates according to the control current input from the controller 30. Specifically, the proportional valve 31BL uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other inlet port of the shuttle valve 32BL. Thereby, the proportional valve 31BL can adjust the pilot pressure acting on the right pilot port of the control valve 175L and the left pilot port of the control valve 175R via the shuttle valve 32BL.

[0097] The proportional valve 31BR operates according to the control current input from the controller 30. Specifically, the proportional valve 31BR utilizes the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other inlet port of the shuttle valve 32BR. Thereby, the proportional valve 31BR can adjust the pilot pressure acting on the right pilot port of the control valve 175R via the shuttle valve 32BR.

[0098] That is, the proportional valves 31BL and 31BR can adjust the pilot pressure output to the secondary side so that the control valves 175L and 175R can be stopped at an arbitrary valve position regardless of the operating state of the right operation lever 26R.

[0099] The proportional valve 33BL for pressure reduction operates according to the control current input from the controller 30. Specifically, when no control current from the controller 30 is input, the proportional valve 33BL for pressure reduction directly outputs the pilot pressure corresponding to the boom raising operation of the right operation lever 26R to the secondary side. On the other hand, when control current from the controller 30 is input, the proportional valve 33BL for pressure reduction reduces the pilot pressure of the pilot line on the secondary side corresponding to the boom raising operation of the right operation lever 26R to an extent corresponding to the control current, and outputs the reduced pilot pressure to one inlet port of the shuttle valve 32BL. Thereby, even when a boom raising operation is being performed with the right operation lever 26R, the proportional valve 33BL for pressure reduction can forcibly suppress or stop the operation of the boom cylinder 7 corresponding to the boom raising operation as needed. Also, even when a boom raising operation is being performed with the right operation lever 26R, the proportional valve 33BL for pressure reduction can make the pilot pressure acting on one inlet port of the shuttle valve 32BL lower than the pilot pressure acting on the other inlet port of the shuttle valve 32BL from the proportional valve 31BL. Therefore, the controller 30 can control the proportional valve 31BL and the proportional valve 33BL for pressure reduction to reliably apply a desired pilot pressure to the boom raising side pilot ports of the control valves 175L and 175R.

[0100] The proportional valve 33BR for pressure reduction operates according to the control current input from the controller 30. Specifically, when no control current is input from the controller 30, the proportional valve 33BR for pressure reduction directly outputs the pilot pressure corresponding to the boom lowering operation of the right operation lever 26R to the secondary side. On the other hand, when the control current from the controller 30 is input, the proportional valve 33BR for pressure reduction reduces the pilot pressure of the pilot line on the secondary side corresponding to the boom lowering operation of the right operation lever 26R to an extent according to the control current, and outputs the reduced pilot pressure to one inlet port of the shuttle valve 32BR. Thereby, even when the boom lowering operation is being performed by the right operation lever 26R, the proportional valve 33BR for pressure reduction can forcibly suppress or stop the operation of the boom cylinder 7 corresponding to the boom lowering operation as necessary. Also, even when the boom lowering operation is being performed by the right operation lever 26R, the proportional valve 33BR for pressure reduction can make the pilot pressure acting on one inlet port of the shuttle valve 32BR lower than the pilot pressure acting on the other inlet port of the shuttle valve 32BR from the proportional valve 31BR. Therefore, the controller 30 can control the proportional valve 31BR and the proportional valve 33BR for pressure reduction to surely act a desired pilot pressure on the boom lowering side pilot ports of the control valves 175L, 175R.

[0101] In this way, the proportional valves 33BL, 33BR for pressure reduction can forcibly suppress or stop the operation of the boom cylinder 7 corresponding to the operation state of the right operation lever 26R in the front-rear direction. Also, the proportional valves 33BL, 33BR for pressure reduction can lower the pilot pressure acting on one inlet port of the shuttle valves 32BL, 32BR, and assist so that the pilot pressure of the proportional valves 31BL, 31BR surely acts on the pilot ports of the control valves 175L, 175R through the shuttle valves 32BL, 32BR.

[0102] Still, instead of controlling the pressure reducing proportional valve 33BL, the controller 30 may forcibly suppress or stop the operation of the boom cylinder 7 corresponding to the boom raising operation of the right operation lever 26R by controlling the proportional valve 31BR. For example, when the boom raising operation is performed with the right operation lever 26R, the controller 30 controls the proportional valve 31BR and applies a predetermined pilot pressure to the boom lowering side pilot ports of the control valves 175L and 175R via the shuttle valve 32BR from the proportional valve 31BR. Thereby, the pilot pressure acts on the boom lowering side pilot ports of the control valves 175L and 175R in a form that counteracts the pilot pressure acting on the boom raising side pilot ports of the control valves 175L and 175R via the shuttle valve 32BL from the right operation lever 26R. Therefore, the controller 30 can forcibly bring the control valves 175L and 175R closer to the neutral position to suppress or stop the operation of the boom cylinder 7 corresponding to the boom raising operation of the right operation lever 26R. Similarly, instead of controlling the pressure reducing proportional valve 33BR, the controller 30 may forcibly suppress or stop the operation of the boom cylinder 7 corresponding to the boom lowering operation of the right operation lever 26R by controlling the proportional valve 31BL.

[0103] The operation pressure sensor 29RA detects the operation content in the front - rear direction of the right operation lever 26R by the operator in the form of pressure (operation pressure), and the detection signal corresponding to the detected pressure is taken into the controller 30. Thereby, the controller 30 can grasp the operation content in the front - rear direction of the right operation lever 26R.

[0104] The controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the pilot port on the right side of the control valve 175L and the pilot port on the left side of the control valve 175R via the proportional valve 31BL and the shuttle valve 32BL, regardless of the boom raising operation on the right operation lever 26R by the operator. Also, the controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the pilot port on the right side of the control valve 175R via the proportional valve 31BR and the shuttle valve 32BR, regardless of the boom lowering operation on the right operation lever 26R by the operator. That is, the controller 30 can automatically control the raising and lowering operations of the boom 4 and realize the automatic operation function, remote operation function, etc. of the excavator 100.

[0105] As shown in FIG. 4C, the right operation lever 26R is used to operate the bucket cylinder 9 corresponding to the bucket 6 in a manner where the operator tilts in the left-right direction. That is, when the right operation lever 26R is tilted in the left-right direction, the operation of the bucket 6 is the operation target. The right operation lever 26R utilizes the hydraulic oil discharged from the pilot pump 15 and outputs a pilot pressure corresponding to the operation content in the left-right direction to the secondary side.

[0106] The two inlet ports of the shuttle valve 32CL are respectively connected to the secondary pilot line of the right operation lever 26R corresponding to the closing operation of the bucket 6 (hereinafter, "bucket closing operation") and the secondary pilot line of the proportional valve 31CL, and the outlet port is connected to the pilot port on the left side of the control valve 174.

[0107] The two inlet ports of the shuttle valve 32CR are respectively connected to the secondary pilot line of the right operation lever 26R corresponding to the opening operation of the bucket 6 (hereinafter, "bucket opening operation") and the secondary pilot line of the proportional valve 31CR, and the outlet port is connected to the pilot port on the right side of the control valve 174.

[0108] That is, the right operation lever 26R causes a pilot pressure corresponding to the operation content in the left-right direction to act on the pilot port of the control valve 174 via the shuttle valves 32CL and 32CR. Specifically, when the bucket closing operation is performed, the right operation lever 26R outputs a pilot pressure corresponding to the operation amount to one inlet port of the shuttle valve 32CL, and causes it to act on the left pilot port of the control valve 174 via the shuttle valve 32CL. Further, when the bucket opening operation is performed, the right operation lever 26R outputs a pilot pressure corresponding to the operation amount to one inlet port of the shuttle valve 32CR, and causes it to act on the right pilot port of the control valve 174 via the shuttle valve 32CR.

[0109] The proportional valve 31CL operates according to the control current input from the controller 30. Specifically, the proportional valve 31CL uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other pilot port of the shuttle valve 32CL. Thereby, the proportional valve 31CL can adjust the pilot pressure acting on the left pilot port of the control valve 174 via the shuttle valve 32CL.

[0110] The proportional valve 31CR operates according to the control current output by the controller 30. Specifically, the proportional valve 31CR uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other pilot port of the shuttle valve 32CR. Thereby, the proportional valve 31CR can adjust the pilot pressure acting on the right pilot port of the control valve 174 via the shuttle valve 32CR.

[0111] That is, the proportional valves 31CL and 31CR can adjust the pilot pressure output to the secondary side so that the control valve 174 can be stopped at an arbitrary valve position regardless of the operation state of the right operation lever 26R.

[0112] The proportional valve 33CL for pressure reduction operates according to the control current input from the controller 30. Specifically, when no control current is input from the controller 30, the proportional valve 33CL for pressure reduction directly outputs the pilot pressure corresponding to the bucket closing operation of the right operation lever 26R to the secondary side. On the other hand, when the control current is input from the controller 30, the proportional valve 33CL for pressure reduction reduces the pilot pressure of the pilot line on the secondary side corresponding to the bucket closing operation of the right operation lever 26R to an extent according to the control current, and outputs the reduced pilot pressure to one of the inlet ports of the shuttle valve 32CL. Thereby, even when the bucket closing operation is being performed by the right operation lever 26R, the proportional valve 33CL for pressure reduction can, if necessary, forcibly suppress or stop the operation of the bucket cylinder 9 corresponding to the bucket closing operation. Also, even when the bucket closing operation is being performed by the right operation lever 26R, the proportional valve 33CL for pressure reduction can make the pilot pressure acting on one of the inlet ports of the shuttle valve 32CL lower than the pilot pressure acting on the other inlet port of the shuttle valve 32CL from the proportional valve 31CL. Therefore, the controller 30 can control the proportional valve 31CL and the proportional valve 33CL for pressure reduction to reliably actuate a desired pilot pressure on the pilot port on the bucket closing side of the control valve 174.

[0113] The proportional valve 33CR for pressure reduction operates according to the control current input from the controller 30. Specifically, when no control current is input from the controller 30, the proportional valve 33CR for pressure reduction directly outputs the pilot pressure corresponding to the bucket opening operation of the right operation lever 26R to the secondary side. On the other hand, when the control current from the controller 30 is input, the proportional valve 33CR for pressure reduction reduces the pilot pressure of the pilot line on the secondary side corresponding to the bucket opening operation of the right operation lever 26R to an extent according to the control current, and outputs the reduced pilot pressure to one inlet port of the shuttle valve 32CR. Thereby, even when the bucket opening operation is being performed by the right operation lever 26R, the proportional valve 33CR for pressure reduction can forcibly suppress or stop the operation of the bucket cylinder 9 corresponding to the bucket opening operation as needed. Also, even when the bucket opening operation is being performed by the right operation lever 26R, the proportional valve 33CR for pressure reduction can make the pilot pressure acting on one inlet port of the shuttle valve 32CR lower than the pilot pressure acting on the other inlet port of the shuttle valve 32CR from the proportional valve 31CR. Therefore, the controller 30 can control the proportional valve 31CR and the proportional valve 33CR for pressure reduction to surely act a desired pilot pressure on the pilot port on the bucket opening side of the control valve 174.

[0114] In this way, the proportional valves 33CL and 33CR for pressure reduction can forcibly suppress or stop the operation of the bucket cylinder 9 corresponding to the left - right direction operation state of the right operation lever 26R. Also, the proportional valves 33CL and 33CR for pressure reduction can lower the pilot pressure acting on one inlet port of the shuttle valves 32CL and 32CR, and assist to ensure that the pilot pressure of the proportional valves 31CL and 31CR acts on the pilot port of the control valve 174 through the shuttle valves 32CL and 32CR.

[0115] Still, instead of controlling the pressure reducing proportional valve 33CL, the controller 30 may forcibly suppress or stop the operation of the bucket cylinder 9 corresponding to the bucket closing operation of the right operation lever 26R by controlling the proportional valve 31CR. For example, when a bucket closing operation is performed with the right operation lever 26R, the controller 30 controls the proportional valve 31CR, and a predetermined pilot pressure may be applied from the proportional valve 31CR to the pilot port on the bucket opening side of the control valve 174 via the shuttle valve 32CR. Thereby, the pilot pressure acts on the pilot port on the bucket opening side of the control valve 174 in a manner that counteracts the pilot pressure acting on the pilot port on the bucket closing side of the control valve 174 via the shuttle valve 32CL from the right operation lever 26R. Therefore, the controller 30 can forcibly bring the control valve 174 closer to the neutral position and suppress or stop the operation of the bucket cylinder 9 corresponding to the bucket closing operation of the right operation lever 26R. Similarly, instead of controlling the pressure reducing proportional valve 33CR, the controller 30 may forcibly suppress or stop the operation of the bucket cylinder 9 corresponding to the bucket opening operation of the right operation lever 26R by controlling the proportional valve 31CL.

[0116] The operation pressure sensor 29RB detects the operation content in the left - right direction with respect to the right operation lever 26R by the operator in the form of pressure (operation pressure), and the detection signal corresponding to the detected pressure is taken into the controller 30. Thereby, the controller 30 can grasp the operation content in the left - right direction of the right operation lever 26R.

[0117] The controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the pilot port on the left side of the control valve 174 via the proportional valve 31CL and the shuttle valve 32CL, regardless of the bucket closing operation on the right operation lever 26R by the operator. Also, the controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the pilot port on the right side of the control valve 174 via the proportional valve 31CR and the shuttle valve 32CR, regardless of the bucket opening operation on the right operation lever 26R by the operator. That is, the controller 30 can automatically control the opening and closing operation of the bucket 6 and realize the automatic operation function, remote operation function, etc. of the excavator 100.

[0118] Also, for example, as shown in FIG. 4D, the left operation lever 26L is used to operate the swing hydraulic motor 2A corresponding to the upper swing body 3 (swing mechanism 2) in a manner where the operator tilts in the left - right direction. That is, when the left operation lever 26L is tilted in the left - right direction, the swing operation of the upper swing body 3 is the operation target. The left operation lever 26L utilizes the hydraulic oil discharged from the pilot pump 15 and outputs a pilot pressure corresponding to the operation content in the left - right direction to the secondary side.

[0119] The shuttle valve 32DL has two inlet ports connected to the secondary - side pilot line of the left operation lever 26L corresponding to the left - hand swing operation (hereinafter, "left swing operation") of the upper swing body 3 and the secondary - side pilot line of the proportional valve 31DL, respectively, and an outlet port connected to the pilot port on the left side of the control valve 173.

[0120] The shuttle valve 32DR has two inlet ports connected to the secondary - side pilot line of the left operation lever 26L corresponding to the right - hand swing operation (hereinafter, "right swing operation") of the upper swing body 3 and the secondary - side pilot line of the proportional valve 31DR, respectively, and an outlet port connected to the pilot port on the right side of the control valve 173.

[0121] That is, the left operation lever 26L acts on the pilot port of the control valve 173 with a pilot pressure corresponding to the operation content in the left - right direction via the shuttle valves 32DL and 32DR. Specifically, when the left operation lever 26L is turned left, it outputs a pilot pressure corresponding to the operation amount to one inlet port of the shuttle valve 32DL, and via the shuttle valve 32DL, it acts on the left pilot port of the control valve 173. Also, when the left operation lever 26L is turned right, it outputs a pilot pressure corresponding to the operation amount to one inlet port of the shuttle valve 32DR, and via the shuttle valve 32DR, it acts on the right pilot port of the control valve 173.

[0122] The proportional valve 31DL operates according to the control current input from the controller 30. Specifically, the proportional valve 31DL uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other pilot port of the shuttle valve 32DL. Thereby, the proportional valve 31DL can adjust the pilot pressure acting on the left pilot port of the control valve 173 via the shuttle valve 32DL.

[0123] The proportional valve 31DR operates according to the control current output by the controller 30. Specifically, the proportional valve 31DR uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other pilot port of the shuttle valve 32DR. Thereby, the proportional valve 31DR can adjust the pilot pressure acting on the right pilot port of the control valve 173 via the shuttle valve 32DR.

[0124] That is, the proportional valves 31DL and 31DR can adjust the pilot pressure output to the secondary side so that the control valve 173 can be stopped at an arbitrary valve position regardless of the operation state of the left operation lever 26L.

[0125] The proportional valve 33DL for pressure reduction operates according to the control current input from the controller 30. Specifically, when no control current is input from the controller 30, the proportional valve 33DL for pressure reduction directly outputs the pilot pressure corresponding to the left rotation operation of the left operation lever 26L to the secondary side. On the other hand, when the control current is input from the controller 30, the proportional valve 33DL for pressure reduction reduces the pilot pressure of the pilot line on the secondary side corresponding to the left rotation operation of the left operation lever 26L to an extent according to the control current, and outputs the reduced pilot pressure to one inlet port of the shuttle valve 32DL. Thereby, even when the left rotation operation is being performed by the left operation lever 26L, the proportional valve 33DL for pressure reduction can forcibly suppress or stop the operation of the swivel hydraulic motor 2A corresponding to the left rotation operation as needed. Also, even when the left rotation operation is being performed by the left operation lever 26L, the proportional valve 33DL for pressure reduction can make the pilot pressure acting on one inlet port of the shuttle valve 32DL lower than the pilot pressure acting on the other inlet port of the shuttle valve 32DL from the proportional valve 31DL. Therefore, the controller 30 can control the proportional valve 31DL and the proportional valve 33DL for pressure reduction to surely actuate the desired pilot pressure on the left rotation side pilot port of the control valve 173.

[0126] The proportional valve 33DR for pressure reduction operates according to the control current input from the controller 30. Specifically, when no control current is input from the controller 30, the proportional valve 33DR for pressure reduction directly outputs the pilot pressure corresponding to the right rotation operation of the left operation lever 26L to the secondary side. On the other hand, when the control current from the controller 30 is input, the proportional valve 33DR for pressure reduction reduces the pilot pressure of the pilot line on the secondary side corresponding to the right rotation operation of the left operation lever 26L to an extent according to the control current, and outputs the reduced pilot pressure to one inlet port of the shuttle valve 32DR. Thereby, even when the right rotation operation is being performed with the left operation lever 26L, the proportional valve 33DR for pressure reduction can forcibly suppress or stop the operation of the swivel hydraulic motor 2A corresponding to the right rotation operation as needed. Also, even when the right rotation operation is being performed with the left operation lever 26L, the proportional valve 33DR for pressure reduction can make the pilot pressure acting on one inlet port of the shuttle valve 32DR lower than the pilot pressure acting on the other inlet port of the shuttle valve 32DR from the proportional valve 31DR. Therefore, the controller 30 can control the proportional valve 31DR and the proportional valve 33DR for pressure reduction to surely act a desired pilot pressure on the pilot port on the right rotation side of the control valve 173.

[0127] In this way, the proportional valves 33DL and 33DR for pressure reduction can forcibly suppress or stop the operation of the swivel hydraulic motor 2A corresponding to the operation state of the left operation lever 26L in the left - right direction. Also, the proportional valves 33DL and 33DR for pressure reduction can lower the pilot pressure acting on one inlet port of the shuttle valves 32DL and 32DR, and assist so that the pilot pressure of the proportional valves 31DL and 31DR surely acts on the pilot port of the control valve 173 through the shuttle valves 32DL and 32DR.

[0128] Further, instead of controlling the pressure reducing proportional valve 33DL, the controller 30 may forcibly suppress or stop the operation of the swing hydraulic motor 2A corresponding to the left turn operation of the left operation lever 26L by controlling the proportional valve 31DR. For example, when a left turn operation is performed with the left operation lever 26L, the controller 30 controls the proportional valve 31DR, and a predetermined pilot pressure may be applied from the proportional valve 31DR to the right turn side pilot port of the control valve 173 via the shuttle valve 32DR. Thereby, the pilot pressure acts on the right turn side pilot port of the control valve 173 in a manner that counteracts the pilot pressure acting on the left turn side pilot port of the control valve 173 via the shuttle valve 32DL from the left operation lever 26L. Therefore, the controller 30 can forcibly bring the control valve 173 closer to the neutral position to suppress or stop the operation of the swing hydraulic motor 2A corresponding to the left turn operation of the left operation lever 26L. Similarly, instead of controlling the pressure reducing proportional valve 33DR, the controller 30 may forcibly suppress or stop the operation of the swing hydraulic motor 2A corresponding to the right turn operation of the left operation lever 26L by controlling the proportional valve 31DL.

[0129] The operation pressure sensor 29LB detects the operation state of the left operation lever 26L by the operator as pressure, and the detection signal corresponding to the detected pressure is taken into the controller 30. Thereby, the controller 30 can grasp the operation content in the left-right direction with respect to the left operation lever 26L.

[0130] The controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the pilot port on the left side of the control valve 173 via the proportional valve 31DL and the shuttle valve 32DL, regardless of the left turning operation of the left operation lever 26L by the operator. Further, the controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the pilot port on the right side of the control valve 173 via the proportional valve 31DR and the shuttle valve 32DR, regardless of the right turning operation of the left operation lever 26L by the operator. That is, the controller 30 can automatically control the turning operation of the upper swing body 3 in the left-right direction, and realize the automatic operation function, remote operation function, etc. of the excavator 100.

[0131] In addition, for the lower traveling body 1 as well, a configuration that can be automatically controlled by the controller 30 may be adopted in the same manner as the boom 4, the arm 5, the bucket 6, and the upper swing body 3. In this case, for example, a shuttle valve 32 is installed in the secondary pilot line between each of the left travel lever 26DL and the right travel lever 26DR and the control valves 171, 172, and a proportional valve 31 that is connected to the shuttle valve 32 and can be controlled by the controller 30 is installed. Thereby, the controller 30 can automatically control the traveling operation of the lower traveling body 1 by outputting a control current to the proportional valve 31, and realize the automatic operation function, remote operation function, etc. of the excavator 100.

[0132] Subsequently, the control system of the excavator 100 according to the present embodiment includes a controller 30, a space recognition device 70, an orientation detection device 71, an input device 72, a positioning device 73, a display device D1, an audio output device D2, a boom angle sensor S1, an arm angle sensor S2, a bucket angle sensor S3, a body inclination sensor S4, and a swing state sensor S5.

[0133] The controller 30 performs control regarding the excavator 100 as described above.

[0134] For example, the controller 30 sets a target rotational speed based on a work mode or the like preset by a predetermined operation on an input device 72 such as an operator, and performs drive control to rotate the engine 11 at a constant speed.

[0135] Also, for example, the controller 30 outputs a control command to the regulator 13 as necessary to change the discharge amount of the main pump 14.

[0136] Also, for example, when the operating device 26 is electric, the controller 30 may control the proportional valve 31 as described above to realize the operation of the hydraulic actuator according to the operation content of the operating device 26.

[0137] Also, for example, the controller 30 may use the proportional valve 31 to realize remote operation of the excavator 100. Specifically, the controller 30 may output a control command corresponding to the content of the remote operation specified by the remote operation signal received from an external device to the proportional valve 31. Then, the proportional valve 31 may output a pilot pressure corresponding to the control command from the controller 30 using the hydraulic oil supplied from the pilot pump 15, and apply the pilot pressure to the pilot port of the corresponding control valve in the control valve 17. Thereby, the content of the remote operation is reflected in the operation of the control valve 17, and the operations of various operation elements (driven elements) along the content of the remote operation are realized by the hydraulic actuator.

[0138] Also, for example, the controller 30 performs control related to the peripheral monitoring function. In the peripheral monitoring function, based on the information acquired by the space recognition device 70, the entry of an object to be monitored into a predetermined range (hereinafter, "monitoring range") around the excavator 100 is monitored. The determination process for the entry of the object to be monitored into the monitoring range may be performed by the space recognition device 70 or may be performed outside the space recognition device 70 (for example, the controller 30). The objects to be monitored may include, for example, people, trucks, other construction machines, utility poles, suspended loads, pylons, buildings, etc.

[0139] Further, for example, the controller 30 performs control related to the object detection notification function. In the object detection notification function, when it is determined by the peripheral monitoring function that there is an object to be monitored within the monitoring range, the presence of the object to be monitored around the operator in the cabin 10 or the excavator 100 is notified. The controller 30 may implement the object detection notification function using, for example, the display device D1 and the audio output device D2.

[0140] Further, for example, the controller 30 performs control related to the operation restriction function. In the operation restriction function, for example, when it is determined by the peripheral monitoring function that there is an object to be monitored within the monitoring target, the operation of the excavator 100 is restricted. Hereinafter, the case where the object to be monitored is a person will be mainly described.

[0141] For example, before the actuator operates, if the controller 30 determines that there is an object to be monitored, such as a person, within a predetermined range (monitoring range) from the excavator 100 based on the acquired information of the space recognition device 70, even if the operator operates the operating device 26, the actuator may be disabled or restricted to operate at a very low speed. Specifically, when the controller 30 determines that there is a person within the monitoring range, it can disable the actuator by locking the gate lock valve. In the case of the electric operating device 26, the actuator can be disabled by invalidating the signal from the controller 30 to the proportional valve for operation (proportional valve 31). The same applies to other types of operating devices 26 when a proportional valve for operation (proportional valve 31) that outputs a pilot pressure corresponding to the control command from the controller 30 and applies the pilot pressure to the pilot port of the corresponding control valve in the control valve 17 is used. When it is desired to make the actuator operate at a very low speed, the operation of the actuator can be made to be in a very low speed state by restricting the control signal from the controller 30 to the proportional valve for operation (proportional valve 31) to correspond to a relatively small pilot pressure. Thus, when it is determined that the detected object to be monitored exists within the monitoring range, the actuator is not driven even if the operating device 26 is operated, or is driven at an operating speed (very low speed) smaller than the operating speed corresponding to the operation input to the operating device 26. Further, if it is determined that there is an object to be monitored, such as a person, within the monitoring range while the operator is operating the operating device 26, the operation of the actuator may be stopped or decelerated regardless of the operator's operation. Specifically, when it is determined that there is a person within the monitoring range, the actuator may be stopped by locking the gate lock valve. When a proportional valve for operation (proportional valve 31) that outputs a pilot pressure corresponding to the control command from the controller 30 and applies the pilot pressure to the pilot port of the corresponding control valve in the control valve is used, the actuator can be disabled or restricted to operate in a very low speed state by invalidating the signal from the controller 30 to the proportional valve for operation (proportional valve 31) or outputting a deceleration command to the proportional valve for operation (proportional valve 31).Also, when the detected object to be monitored is a truck, the control regarding the stop or deceleration of the actuator may not be performed. For example, the actuator may be controlled to avoid the detected truck. Thus, the type of the detected object may be recognized, and based on the recognition, the actuator may be controlled.

[0142] The space recognition device 70 is configured to recognize an object existing in the three-dimensional space around the excavator 100 and measure (calculate) a positional relationship such as the distance from the space recognition device 70 or the excavator 100 to the recognized object. The space recognition device 70 may include, for example, an ultrasonic sensor, a millimeter-wave radar, a monocular camera, a stereo camera, LIDAR (Light Detecting and Ranging), a distance image sensor, an infrared sensor, etc. In the present embodiment, the space recognition device 70 includes a front recognition sensor 70F attached to the front end of the upper surface of the cab 10, a rear recognition sensor 70B attached to the rear end of the upper surface of the upper swing body 3, a left recognition sensor 70L attached to the left end of the upper surface of the upper swing body 3, and a right recognition sensor 70R attached to the right end of the upper surface of the upper swing body 3. Further, an upper recognition sensor for recognizing an object existing in the space above the upper swing body 3 may be attached to the excavator 100.

[0143] The orientation detection device 71 detects information regarding the relative relationship between the orientation of the upper swing body 3 and the orientation of the lower traveling body 1 (for example, the swing angle of the upper swing body 3 with respect to the lower traveling body 1).

[0144] The orientation detection device 71 may include, for example, a combination of a geomagnetic sensor attached to the lower traveling body 1 and a geomagnetic sensor attached to the upper slewing body 3. Further, the orientation detection device 71 may include a combination of a GNSS receiver attached to the lower traveling body 1 and a GNSS receiver attached to the upper slewing body 3. Further, the orientation detection device 71 may include a rotary encoder, a rotary position sensor, etc. that can detect the relative slewing angle of the upper slewing body 3 with respect to the lower traveling body 1, that is, the above-described slewing state sensor S5. For example, it may be attached to a center joint provided in relation to the slewing mechanism 2 that realizes the relative rotation between the lower traveling body 1 and the upper slewing body 3. Further, the orientation detection device 71 may include a camera attached to the upper slewing body 3. In this case, the orientation detection device 71 performs known image processing on the image (input image) captured by the camera attached to the upper slewing body 3 to detect the image of the lower traveling body 1 included in the input image. Then, the orientation detection device 71 may identify the longitudinal direction of the lower traveling body 1 by detecting the image of the lower traveling body 1 using a known image recognition technique, and derive the angle formed between the direction of the front-rear axis of the upper slewing body 3 and the longitudinal direction of the lower traveling body 1. At this time, the direction of the front-rear axis of the upper slewing body 3 can be derived from the attachment position of the camera. In particular, since the crawler 1C protrudes from the upper slewing body 3, the orientation detection device 71 can identify the longitudinal direction of the lower traveling body 1 by detecting the image of the crawler 1C.

[0145] In addition, when the upper slewing body 3 is driven to slewing by an electric motor instead of the slewing hydraulic motor 2A, the orientation detection device 71 may be a resolver.

[0146] The input device 72 is provided within reach of a seated operator in the cabin 10, receives various operation inputs from the operator, and outputs a signal corresponding to the operation input to the controller 30. For example, the input device 72 may include a touch panel implemented on the display of a display device that displays various information images. Also, for example, the input device 72 may include button switches, levers, toggles, etc. installed around the display device D1. Further, the input device 72 may include a knob switch provided on the operating device 26 (for example, the switch NS provided on the left operating lever 26L). A signal corresponding to the operation content for the input device 72 is taken into the controller 30.

[0147] The switch NS is, for example, a push button switch provided at the tip of the left operating lever 26L. The operator can operate the left operating lever 26L while pressing the switch NS. Also, the switch NS may be provided on the right operating lever 26R or at other positions within the cabin 10.

[0148] The positioning device 73 measures the position and orientation of the upper swing body 3. The positioning device 73 is, for example, a GNSS (Global Navigation Satellite System) compass, detects the position and orientation of the upper swing body 3, and a detection signal corresponding to the position and orientation of the upper swing body 3 is taken into the controller 30. Also, the function of detecting the orientation of the upper swing body 3 among the functions of the positioning device 73 may be replaced by an azimuth sensor attached to the upper swing body 3.

[0149] The display device D1 is provided at a location easily visible to a seated operator in the cabin 10 and displays various information images under the control of the controller 30. The display device D1 may be connected to the controller 30 via an in-vehicle communication network such as CAN (Controller Area Network), or may be connected to the controller 30 via a one-to-one dedicated line.

[0150] The voice output device D2 is provided, for example, inside the cabin 10, connected to the controller 30, and outputs voice under the control of the controller 30. The voice output device D2 is, for example, a speaker, a buzzer, or the like. The voice output device D2 outputs various information as voice in response to a voice output command from the controller 30.

[0151] The boom angle sensor S1 is attached to the boom 4 and detects the pitching angle of the boom 4 with respect to the upper slewing body 3 of the boom 4 (hereinafter, "boom angle"), for example, in a side view, the angle formed by the straight line connecting the fulcrums at both ends of the boom 4 with respect to the slewing plane of the upper slewing body 3. The boom angle sensor S1 may include, for example, a rotary encoder, an acceleration sensor, a gyro sensor (angular velocity sensor), a 6-axis sensor, an IMU (Inertial Measurement Unit), etc. The same applies to the arm angle sensor S2, the bucket angle sensor S3, and the body tilt sensor S4 below. The detection signal corresponding to the boom angle by the boom angle sensor S1 is taken into the controller 30.

[0152] The arm angle sensor S2 is attached to the arm 5 and detects the rotation angle of the arm 5 with respect to the boom 4 (hereinafter, "arm angle"), for example, in a side view, the angle formed by the straight line connecting the fulcrums at both ends of the arm 5 with respect to the straight line connecting the fulcrums at both ends of the boom 4. The detection signal corresponding to the arm angle by the arm angle sensor S2 is taken into the controller 30.

[0153] The bucket angle sensor S3 is attached to the bucket 6 and detects the rotation angle of the bucket 6 with respect to the arm 5 (hereinafter, "bucket angle"), for example, in a side view, the angle formed by the straight line connecting the fulcrum and the tip (cutting edge) of the bucket 6 with respect to the straight line connecting the fulcrums at both ends of the arm 5. The detection signal corresponding to the bucket angle by the bucket angle sensor S3 is taken into the controller 30.

[0154] The machine body tilt sensor S4 detects the tilt state of the machine body (for example, the upper swing body 3) with respect to the horizontal plane. The machine body tilt sensor S4 is attached to, for example, the upper swing body 3 and detects the tilt angles (hereinafter, "front-rear tilt angle" and "left-right tilt angle") around two axes in the front-rear direction and the left-right direction of the excavator 100 (that is, the upper swing body 3). The machine body tilt sensor S4 may include, for example, an acceleration sensor, a gyro sensor (angular velocity sensor), a six-axis sensor, an IMU, etc. The detection signals corresponding to the tilt angles (front-rear tilt angle and left-right tilt angle) by the machine body tilt sensor S4 are taken into the controller 30.

[0155] The slewing state sensor S5 is attached to the upper swing body 3 and outputs detection information regarding the slewing state of the upper swing body 3. The slewing state sensor S5 detects, for example, the slewing angular velocity and the slewing angle of the upper swing body 3. The slewing state sensor S5 includes, for example, a gyro sensor, a resolver, a rotary encoder, etc.

[0156] In addition, when the machine body tilt sensor S4 includes a gyro sensor, a six-axis sensor, an IMU, etc. that can detect the angular velocity around three axes, the slewing state (for example, the slewing angular velocity) of the upper swing body 3 may be detected based on the detection signal of the machine body tilt sensor S4. In this case, the slewing state sensor S5 may be omitted.

[0157] [Overview of the Machine Guidance Function and Machine Control Function of the Excavator] Next, with reference to FIG. 5, an overview of the machine guidance function and machine control function of the excavator will be described.

[0158] FIG. 5 is a block diagram showing an example of the configuration related to the machine guidance function and machine control function of the excavator 100.

[0159] The controller 30 executes control of the excavator 100 related to the machine guidance function that guides (guides) the manual operation of the excavator 100 by the operator, for example.

[0160] The controller 30 transmits work information such as the distance between the target construction surface (an example of the design surface) and the tip of the attachment AT, specifically, the working part of the end attachment, to the operator through the display device D1, the voice output device D2, etc. Specifically, the controller 30 acquires information from the boom angle sensor S1, the arm angle sensor S2, the bucket angle sensor S3, the machine body inclination sensor S4, the slewing state sensor S5, the space recognition device 70, the positioning device V1, the input device 72, etc. Then, the controller 30 may calculate the distance between the bucket 6 and the target construction surface based on the acquired information, for example, and notify the operator of the calculated distance by the image displayed on the display device D1 or the voice output from the voice output device D2. Data regarding the target construction surface is stored in, for example, an internal memory or an external storage device connected to the controller 30 by being set and input through the input device 72 by the operator or by being downloaded from the outside (for example, a predetermined management server). Data regarding the target construction surface is expressed in, for example, a reference coordinate system. The reference coordinate system is, for example, the World Geodetic System. The World Geodetic System is a three-dimensional orthogonal XYZ coordinate system with the origin at the center of gravity of the earth, the X-axis in the direction of the intersection of the Greenwich meridian and the equator, the Y-axis in the direction of 90 degrees east longitude, and the Z-axis in the direction of the North Pole. For example, the operator may set the target construction surface based on the relative positional relationship with a reference point by designating an arbitrary point at the construction site as the reference point through the input device 72. The working part of the bucket 6 is, for example, the tip of the bucket 6, the back surface of the bucket 6, etc. Also, when a breaker is adopted as the end attachment instead of the bucket 6, for example, the tip of the breaker corresponds to the working part. Thereby, the controller 30 can notify the operator of the work information through the display device D1, the voice output device D2, etc., and guide the operation of the excavator 100 by the operator through the operation device 26.

[0161] Further, the controller 30 executes control of the excavator 100 regarding a machine control function for assisting, for example, manual operation of the excavator 100 by an operator or automatically or autonomously operating the excavator 100. Specifically, the controller 30 is configured to acquire a target trajectory which is a trajectory followed by a predetermined part of the attachment (for example, a working part of the end attachment). For example, the controller 30 derives the target trajectory based on data regarding a target construction surface stored in an internal or externally communicable non-volatile storage device. The controller 30 may derive the target trajectory based on information regarding the terrain around the excavator 100 recognized by the space recognition device 70. Further, the controller 30 derives information regarding a past trajectory of a working part such as the tip of the bucket 6 from past outputs of a posture detection device (for example, a boom angle sensor S1, an arm angle sensor S2, a bucket angle sensor S3, etc.) temporarily stored in an internal volatile storage device, and may derive the target trajectory based on that information. Further, the controller 30 may derive the target trajectory based on the current position of a predetermined part of the attachment and data regarding the target construction surface.

[0162] When, for example, an operator is manually performing ground excavation operations, leveling operations, etc., the controller 30 automatically operates at least one of the boom 4, the arm 5, and the bucket 6 so that the target construction surface coincides with the tip position of the bucket 6, specifically, the working parts such as the tips or the back surface of the bucket 6. Specifically, when the operator operates (pushes) the switch NS and operates the arm 5 through the left operation lever 26L, the controller 30 automatically operates the boom 4, the arm 5, and the bucket 6 so that the target construction surface coincides with the working part of the bucket 6 according to the operation of the arm 5 by the operator. Specifically, as described above, the controller 30 controls the proportional valve 31 and automatically operates the boom 4, the arm 5, and the bucket 6. Thereby, the operator can cause the excavator 100 to perform excavation work, leveling work, etc. along the target construction surface only by operating the left operation lever 26L in the front-rear direction. Hereinafter, on the premise that the machine control function is enabled when the switch NS is pressed and the operation of the arm 5 of the left operation lever 26L (that is, the tilting operation of the left operation lever 26L in the front-rear direction) is performed, the description will proceed.

[0163] [Details of the Machine Control Function of the Excavator] Next, with reference to FIG. 6 (FIGS. 6A to 6C), the details of the machine control function will be described.

[0164] FIGS. 6A and 6B are functional block diagrams showing an example of the detailed configuration related to the machine control function of the excavator 100 according to the present embodiment. Specifically, FIGS. 6A and 6B are functional block diagrams showing the detailed configuration related to the semi-automatic operation function of the excavator 100. FIG. 6C is a functional block diagram showing the detailed configuration related to the autonomous operation function of the excavator 100. Since the components described in FIG. 6B are common to both the semi-automatic operation function and the autonomous operation function, the illustration of the corresponding components of the autonomous operation function of the excavator 100 is omitted, and FIG. 6B is appropriately referred to for the description of the autonomous operation function of the excavator 100.

[0165] As shown in FIGS. 6A and 6B, a controller 30 that realizes the semi-automatic operation function of the excavator 100 includes, as functional units related to the machine control function, an operation content acquisition unit 3001, a target construction surface acquisition unit 3002, a target trajectory setting unit 3003, a current position calculation unit 3004, a target position calculation unit 3005, an operation command generation unit 3006, a restriction unit 3007, a pilot command generation unit 3008, and an attitude angle calculation unit 3009. These functional units 3001 to 3009 repeatedly execute the operations described below at a predetermined control cycle, for example, when the switch NS is pressed.

[0166] Also, as shown in FIGS. 6B and 6C, a controller 30 that realizes the autonomous operation function of the excavator 100 includes, as functional units related to the machine control function, a work content acquisition unit 3001A, a target construction surface acquisition unit 3002, a target trajectory setting unit 3003, a current position calculation unit 3004, a target position calculation unit 3005, an operation command generation unit 3006, a restriction unit 3007, a pilot command generation unit 3008, and an attitude angle calculation unit 3009. These functional units 3001A, 3002 to 3009 repeatedly execute the operations described below at a predetermined control cycle, for example, when the autonomous operation function is valid.

[0167] That is, when the controller 30 realizes the autonomous operation function of the excavator 100, it is different from the case of realizing the semi-automatic operation function of the excavator 100 (FIG. 6A) in that it includes a work content acquisition unit 3001A instead of the operation content acquisition unit 3001.

[0168] Based on the detection signal captured from the operation pressure sensor 29LA, the operation content acquisition unit 3001 acquires the operation content regarding the operation of the arm 5 on the left operation lever 26L (i.e., the tilting operation in the front-rear direction). For example, as the operation content, the operation content acquisition unit 3001 acquires (calculates) the operation direction (whether it is an arm opening operation or an arm closing operation) and the operation amount. Also, when the excavator 100 is remotely operated, the semi-automatic operation function of the excavator 100 may be realized based on the content of the remote operation signal received from an external device. In this case, the operation content acquisition unit 3001 acquires the operation content regarding the remote operation based on the remote operation signal received from the external device.

[0169] On the other hand, the work content acquisition unit 3001A acquires information (hereinafter, "work content information") regarding the work content that the excavator 100 should execute from a predetermined external device (for example, the support device 200, the management device 300, etc. described later) through the communication device T1 mounted on the excavator 100. The work content information includes, for example, the content of a predetermined work performed by the excavator 100, the content of the operations constituting the predetermined work, the operation conditions regarding the predetermined work, the trigger conditions for starting the work, etc. The predetermined work may include, for example, excavation work, loading work, leveling work, etc. The operations constituting the predetermined work include, for example, when the predetermined work is excavation work, excavation operation, boom raising and slewing operation, earth discharge operation, and boom lowering and slewing operation, etc. The operation conditions include, for example, when the predetermined work is excavation work, conditions regarding the excavation depth, excavation length, etc. Based on the acquired work content information, the work content acquisition unit 3001A outputs an operation command regarding the operation element (actuator) of the excavator 100.

[0170] The target construction surface acquisition unit 3002 acquires data regarding the target construction surface from, for example, an internal memory or a predetermined external storage device, etc.

[0171] The target trajectory setting unit 3003 sets information on the target trajectory of the tip of the attachment AT (for example, the tip of the bucket 6), specifically, the working part of the end attachment (for example, the tip and the back surface of the bucket 6), for moving the tip of the attachment AT along the target construction surface based on data related to the target construction surface. For example, the target trajectory setting unit 3003 may set, as information on the target trajectory, the inclination angle in the front-rear direction of the target construction surface with respect to the body (upper swing body 3) of the excavator 100. Also, an allowable error range (hereinafter, "allowable error range") may be set for the target trajectory. In this case, the information on the target trajectory may include information on the allowable error range.

[0172] The current position calculation unit 3004 calculates the position (current position) of the tip of the attachment AT (the tip of the bucket 6). Specifically, based on the boom angle β 1 , the arm angle β 2 , and the bucket angle β 3 calculated by the attitude angle calculation unit 3009 described later, the position of the tip of the attachment AT may be calculated.

[0173] The target position calculation unit 3005 calculates the target position of the tip of the attachment AT based on the operator's operation input regarding the arm 5 and the operation content (operation direction and operation amount) regarding remote operation, the information on the set target trajectory, and the current position of the tip of the attachment AT in the semi-automatic operation function of the excavator 100. The target position is the position on the target construction surface (in other words, the target trajectory) that should be reached during the current control cycle assuming that the arm 5 operates according to the operation direction and operation amount in the operator's operation input or remote operation. The target position calculation unit 3005 may calculate the target position of the tip of the attachment AT using, for example, a map, an arithmetic expression, etc. stored in advance in a non-volatile internal memory or the like.

[0174] In addition, in the autonomous driving function of the excavator 100, the target position calculation unit 3005 calculates the target position of the tip (control reference) of the attachment AT based on the operation command input from the work content acquisition unit 3001A, the information on the set target trajectory, and the current position of the control reference (working part) in the attachment AT. Thereby, the controller 30 can autonomously control the excavator 100 without relying on the operator's operation.

[0175] Based on the target position of the tip of the attachment AT, the operation command generation unit 3006 generates a command value (hereinafter, "boom command value") β 1r for the operation of the boom 4, a command value (hereinafter, "arm command value") β 2r for the operation of the arm 5, and a command value ("bucket command value") β 3r for the operation of the bucket 6. For example, the boom command value β 1r , the arm command value β 2r , and the bucket command value β 3r are, respectively, the boom angle, the arm angle, and the bucket angle when the tip of the attachment AT can achieve the target position. The operation command generation unit 3006 includes a master command value generation unit 3006A and a slave command value generation unit 3006B.

[0176] Note that the boom command value, the arm command value, and the bucket command value may be the angular velocities and angular accelerations of the boom 4, the arm 5, and the bucket 6 necessary for the tip of the attachment AT to achieve the target position.

[0177] The master command value generation unit 3006A generates a command value (hereinafter referred to as "master command value") regarding the operation of an operation element (actuator that drives these operation elements) among the operation elements constituting the attachment AT, which operates in response to an operator's operation input or an operation command corresponding to the autonomous driving function (hereinafter referred to as "master element"). Hereinafter, the operation elements that operate in accordance with the operator's operation input or the operation command regarding the autonomous driving function, and the actuators that drive these operation elements may be collectively or individually referred to as master elements, and the same applies to the slave elements described later. In the present embodiment, the master element is the arm 5 (arm cylinder 8), and the master command value generation unit 3006A generates an arm command value β 2r (command value of the first actuator), and outputs it to the arm pilot command generation unit 3008B described later. Specifically, the master command value generation unit 3006A generates an arm command value β 2r corresponding to the content (operation direction and operation amount) of the operator's operation or operation command. For example, the master command value generation unit 3006A may generate and output the arm command value β 2r based on a predetermined map, conversion formula, etc. that defines the relationship between the content of the operator's operation or operation command and the arm command value β 2r .

[0178] The slave command value generation unit 3006B generates a command value (hereinafter referred to as "slave command value") regarding the operation of a slave element that operates in accordance with (synchronously with) the operation of the master element (arm 5) among the operation elements (actuators that drive these operation elements) constituting the attachment AT. Specifically, the slave element operates so that the tip (working part) of the attachment AT, such as the tip of the bucket 6, moves along the target construction surface in accordance with (synchronously with) the operation of the master element (arm 5, arm cylinder 8). In the present embodiment, the slave elements are the boom 4 (boom cylinder 7) and the bucket 6 (bucket cylinder 9), and the slave command value generation unit 3006B generates a boom command value β 1r (command value of the second actuator) and a bucket command value β 3r(Command value of another second actuator) is generated and output to the boom pilot command generation unit 3008A and the bucket pilot command generation unit 3008C described later, respectively. Specifically, the slave command value generation unit 3006B generates the boom command value β 2r and the bucket command value β 1r in accordance with (synchronously with) the operation of the arm 5 corresponding to the arm command value β 3r so that the boom 4 and the bucket 6 operate in accordance with (synchronously with) the operation of the arm 5 and the tip (working part) of the attachment AT can reach the target position (i.e., move along the target construction surface). Thereby, the controller 30 operates the boom 4 and the bucket 6 of the attachment AT in accordance with (i.e., synchronizes with) the operation of the arm 5 corresponding to the operator's operation input or operation command regarding the arm 5, so that the tip (working part) of the attachment AT can be moved along the target construction surface. That is, the arm 5 (arm cylinder 8) operates in response to the operator's operation input or operation command, and the boom 4 (boom cylinder 7) and the bucket 6 (bucket cylinder 9) are controlled to operate in accordance with the operation of the arm 5 so that the tip (working part) of the attachment AT such as the bucket tip of the bucket 6 moves along the target construction surface.

[0179] The restriction unit 3007 restricts (slows down) the operation of the arm 5 output in response to the operator's operation input or operation command when the boom 4 cannot be synchronized with the operation of the arm 5 corresponding to the content of the operator's operation or operation command, or there is a possibility that it cannot be synchronized. Specifically, the restriction unit 3007 determines whether a predetermined condition (hereinafter, "synchronization impossible condition") that can determine that the operation of the boom 4 cannot be synchronized with the operation of the arm 5, or there is a possibility that it cannot be synchronized, is satisfied. The synchronization impossible condition is, for example, the conditions of steps S104 and S110 in FIG. 7 described later. Then, when the synchronization impossible condition is satisfied, the restriction unit 3007 outputs a control command to make the pilot line in a non-communication state to the pressure reducing proportional valves 33AL, 33AR or the switching valve, and a restriction command value Δβ 2ris generated and output to the arm pilot command generation unit 3008B described later. The operation of the arm 5 is determined by the content of the operator's operation input or the operation command corresponding to the autonomous driving function. Therefore, as described above, in accordance with the operation of the arm 5, the boom command value β 1r when is generated, a boom command value β that exceeds the limit of the operation of the boom 4 (for example, the limit of speed and acceleration related to the operation) 1r may be generated. In contrast, the controller 30 can suppress a situation where the operation of the boom 4 cannot be synchronized with the operation of the arm 5 by restricting (slowing down) the operation of the arm 5 to such an extent that the operation of the boom 4 can be synchronized with the operation of the arm 5. The operation of the restriction unit 3007, specifically, the details of the control process (hereinafter, "arm speed restriction process") for restricting the speed and the like related to the operation of the arm 5 will be described later (see FIG. 7).

[0180] In addition, the restriction unit 3007 may generate a restriction command value Δβ 2r and output it to the arm pilot command generation unit 3008B regardless of whether the operation of the boom 4 can be synchronized with the operation of the arm 5. Specifically, when the operation of the boom 4 can be synchronized with the operation of the arm 5 corresponding to the operator's operation or the content of the operation command, the restriction unit 3007 may output a restriction command value Δβ 2r (=0) set to zero to the arm pilot command generation unit 3008B.

[0181] The pilot command generation unit 3008 generates a pilot pressure command value (hereinafter, "pilot pressure command value") for acting on the control valves 174 to 176 to realize the boom angle, arm angle, and bucket angle corresponding to the boom command value β 1r , arm command value β 2r , and bucket command value β 3r . The pilot command generation unit 3008 includes a boom pilot command generation unit 3008A, an arm pilot command generation unit 3008B, and a bucket pilot command generation unit 3008C.

[0182] The boom pilot command generation unit 3008A is the boom command value β 1rBased on the deviation from the calculated value (measured value) of the current boom angle by the boom angle calculation unit 3009A described later, a pilot pressure command value is generated to act on the control valves 175L and 175R corresponding to the boom cylinder 7 that drives the boom 4. Then, the boom pilot command generation unit 3008A outputs a control current corresponding to the generated pilot pressure command value to the proportional valves 31BL and 31BR. As a result, as described above, the pilot pressure corresponding to the pilot pressure command value output from the proportional valves 31BL and 31BR acts on the corresponding pilot ports of the control valves 175L and 175R via the shuttle valves 32BL and 32BR. Then, due to the action of the control valves 175L and 175R, the boom cylinder 7 operates, and the boom 4 operates so as to realize the boom angle corresponding to the boom command value β 1r to operate.

[0183] When the operation of the boom 4 can be synchronized with the operation of the arm 5 (for example, when the limit command value Δβ 2r is not output from the restriction unit 3007), the arm pilot command generation unit 3008B is based on the deviation between the arm command value β 2r and the calculated value (measured value) of the current arm angle by the arm angle calculation unit 3009B described later, and generates a pilot pressure command value to act on the control valves 176L and 176R corresponding to the arm cylinder 8 that drives the arm 5. Then, the arm pilot command generation unit 3008B outputs a control current corresponding to the generated pilot pressure command value to the proportional valves 31AL and 31AR. As a result, as described above, the pilot pressure corresponding to the pilot pressure command value output from the proportional valves 31AL and 31AR acts on the corresponding pilot ports of the control valves 176L and 176R via the shuttle valves 32AL and 32AR. Then, due to the action of the control valves 176L and 176R, the arm cylinder 8 operates, and the arm 5 operates so as to realize the arm angle corresponding to the arm command value β 2r to operate.

[0184] On the other hand, when the operation of the boom 4 cannot be synchronized with the operation of the arm 5, or there is a possibility that they cannot be synchronized (for example, when the limit command value Δβ2r when 2r is output, the arm command value β 2r is corrected by subtracting the limit command value Δβ 2r from it, and a pilot pressure command value to act on the control valves 176L and 176R is generated based on the deviation between the corrected command value (hereinafter referred to as "arm correction command value") and the calculated value (measured value) of the current arm angle. Then, the arm pilot command generation unit 3008B outputs a control current corresponding to the generated pilot pressure command value to the proportional valves 31AL and 31AR. As a result, as described above, the pilot pressure corresponding to the pilot pressure command value output from the proportional valves 31AL and 31AR acts on the corresponding pilot ports of the control valves 176L and 176R via the shuttle valves 32AL and 32AR. Then, due to the action of the control valves 176L and 176R, the arm cylinder 8 operates, and the arm 5 operates so as to realize the arm angle corresponding to the arm correction command value.

[0185] In addition, regarding the semi-automatic operation function (Fig. 6A) of the excavator 100, when the left operation lever 26L is operated by the operator in the cab 10, in a situation where the non-synchronization condition is not satisfied, the arm pilot command generation unit 3008B may omit the generation of the pilot pressure command value and the output of the control current corresponding to the pilot pressure command value to the proportional valves 31AL and 31AR. This is because the pressure reducing proportional valves 33AL and 33AR or the switching valve usually output the pilot pressure corresponding to the operation content of the left operation lever 26L to the secondary side as it is, and can act on the control valves 176L and 176R via the shuttle valves 32AL and 32AR. Also, regarding the semi-automatic operation function (Fig. 6A) of the excavator 100, when the left operation lever 26L is operated by the operator in the cab 10, for the same reason, in a situation where the non-synchronization condition is not satisfied, the operation command generation unit 3006 may omit the generation of the arm command value β 2r For the semi-automatic operation function (Fig. 6A) of the excavator 100, when the left operation lever 26L is operated by the operator in the cab 10, the arm command value β of the operation command generation unit 3006 2rThe function of generating it itself may be omitted. In this case, when the non-synchronizable condition is satisfied, for example, based on the detection signal of the operation pressure sensor 29AL, the command value corresponding to the operation content of the arm 5 in the left operation lever 26L (that is, the arm command value β 2r corresponding command value) is calculated, and a limit command value corresponding to the value obtained by subtracting the above-mentioned limit command value Δβ 2r from the calculated command value is generated and output to the arm pilot command generation unit 3008B. That is, when the non-synchronizable condition is satisfied, the restriction unit 3007 may generate a restriction command value smaller than the command value corresponding to the operation content of the arm 5 in the left operation lever 26L and output it to the arm pilot command generation unit 3008B.

[0186] The bucket pilot command generation unit 3008C generates a pilot pressure command value that acts on the control valve 174 corresponding to the bucket cylinder 9 that drives the bucket 6 based on the deviation between the bucket command value β 3r and the calculated value (measured value) of the current bucket angle by the bucket angle calculation unit 3009C described later. Then, the bucket pilot command generation unit 3008C outputs a control current corresponding to the generated pilot pressure command value to the proportional valves 31CL and 31CR. As a result, as described above, the pilot pressure corresponding to the pilot pressure command value output from the proportional valves 31CL and 31CR acts on the corresponding pilot port of the control valve 174 via the shuttle valves 32CL and 32CR. Then, due to the action of the control valve 174, the bucket cylinder 9 operates, and the bucket 6 operates so as to realize the bucket angle corresponding to the bucket command value β 3r

[0187] The attitude angle calculation unit 3009 calculates (measures) the boom angle, arm angle, and bucket angle (current) based on the detection signals of the boom angle sensor S1, arm angle sensor S2, and bucket angle sensor S3. The attitude angle calculation unit 3009 includes a boom angle calculation unit 3009A, an arm angle calculation unit 3009B, and a bucket angle calculation unit 3009C.

[0188] The boom angle calculation unit 3009A calculates (measures) the boom angle based on the detection signal captured from the boom angle sensor S1. As a result, the boom pilot command generation unit 3008A can perform feedback control regarding the operation of the boom cylinder 7 based on the measurement result of the boom angle calculation unit 3009A.

[0189] The arm angle calculation unit 3009B calculates (measures) the arm angle based on the detection signal captured from the arm angle sensor S2. As a result, the arm pilot command generation unit 3008B can perform feedback control regarding the operation of the arm cylinder 8 based on the measurement result of the arm angle calculation unit 3009B.

[0190] The bucket angle calculation unit 3009C calculates (measures) the bucket angle based on the detection signal captured from the bucket angle sensor S3. As a result, the bucket pilot command generation unit 3008C can perform feedback control regarding the operation of the bucket cylinder 9 based on the measurement result of the bucket angle calculation unit 3009C.

[0191] [Details of Arm Speed Limiting Process] Next, with reference to FIG. 7, the processing flow of the arm speed limiting process by the controller 30 will be described.

[0192] FIG. 7 is a flowchart schematically showing an example of the arm speed limiting process by the controller 30 (specifically, the limiting unit 3007) of the excavator 100 according to the present embodiment.

[0193] In step S102, the limiting unit 3007 acquires a command value (hereinafter, "boom angular velocity command value") corresponding to the angular velocity of the boom 4 (driven by the boom cylinder 7 as the second actuator). For example, the limiting unit 3007 uses the boom command value β generated in the current control cycle 1r and the current (this time) boom angle β calculated by the boom angle calculation unit 3009A 1Based on the difference from [a certain value], the boom angular velocity command value may be calculated. Also, as described above, when the operation command generation unit 3006 generates the boom command value, arm command value, and bucket command value corresponding to the angular velocities of the boom 4, arm 5, and bucket 6 necessary for the tip of the attachment AT to achieve the target position, the restriction unit 3007 may obtain the boom command value generated by the operation command generation unit 3006 as the boom angular velocity command value as it is.

[0194] In step S104, the restriction unit 3007 determines the success or failure of a certain non-synchronizable condition. Specifically, the restriction unit 3007 determines whether the acquired boom angular velocity command value exceeds the upper limit value regarding the angular velocity of the boom 4 (hereinafter, "boom angular velocity upper limit value").

[0195] The boom angular velocity upper limit value is predefined as the limit value of the angular velocity that the boom 4 can output due to the mechanism of the attachment (or a value with a certain margin relative to the limit value), and it may vary depending on various parameters such as the posture of the boom 4, that is, the boom angle, the operating direction of the boom 4 (whether it is the raising direction or the lowering direction), and the output of the engine 11 (the set rotational speed of the engine 11). Therefore, the restriction unit 3007 may calculate the boom angular velocity upper limit value based on the current values of the above-mentioned various parameters using a mechanical model of the attachment of the excavator 100 predefined in advance. Also, the restriction unit 3007 may calculate the boom angular velocity upper limit value using a map or the like that shows the relationship between the predefined boom angular velocity upper limit value and the above-mentioned various parameters based on the current values of the above-mentioned various parameters.

[0196] When the boom angular velocity command value does not exceed the boom angular velocity upper limit value, the restriction unit 3007 determines that the operation of the boom 4 can be synchronized with the operation of the arm 5 and proceeds to step S106. On the other hand, when the boom angular velocity command value exceeds the boom angular velocity upper limit value, the restriction unit 3007 determines that the operation of the boom 4 cannot be synchronized with the operation of the arm 5 and proceeds to step S112.

[0197] Still, in step S102, the limiting unit 3007 may obtain a measured value corresponding to the angular velocity of the boom 4 (hereinafter, "boom angular velocity measured value"), and in step S104, determine whether the boom angular velocity measured value exceeds the above-described boom angular velocity upper limit value. In this case, the limiting unit 3007 may obtain (calculate) the boom angular velocity measured value based on, for example, the difference between the boom angle β calculated in the current control cycle by the boom angle calculation unit 3009A and the boom angle β calculated in the previous control cycle. Further, when the detection signal corresponding to the angular velocity of the boom 4 is included in the detection signal of the boom angle sensor S1, the limiting unit 3007 may calculate the boom angular velocity measured value based on the detection signal. Further, in step S102, the limiting unit 3007 may obtain a command value corresponding to the angular acceleration of the boom 4 (hereinafter, "boom angular acceleration command value"), and in step S104, determine whether the boom angular acceleration command value exceeds a predetermined upper limit value (hereinafter, "boom angular acceleration upper limit value"). In this case, the limiting unit 3007 may calculate the boom angular acceleration command value based on, for example, the boom command value β generated in the current control cycle and the history of the boom angles β calculated in each control cycle by the boom angle calculation unit 3009A for the past several times including the current and previous times. Further, similar to the case of the boom angular velocity upper limit value, the boom angular acceleration upper limit value may be defined in advance as the limit value of the angular acceleration that the boom 4 can output (or a value with a certain margin with respect to the limit value), which may vary depending on various parameters such as the boom angle, the operating direction of the boom 4, and the output of the engine 11. Further, in step S102, the limiting unit 3007 may obtain a measured value corresponding to the angular acceleration of the boom 4 (hereinafter, "boom angular acceleration measured value"), and in step S104, determine whether the boom angular acceleration measured value exceeds the boom angular acceleration upper limit value. 1 and the boom angle β calculated in the previous control cycle 1 and obtain (calculate) the boom angular velocity measured value based on the difference. Further, when the detection signal corresponding to the angular velocity of the boom 4 is included in the detection signal of the boom angle sensor S1, the limiting unit 3007 may calculate the boom angular velocity measured value based on the detection signal. Further, in step S102, the limiting unit 3007 may obtain a command value corresponding to the angular acceleration of the boom 4 (hereinafter, "boom angular acceleration command value"), and in step S104, determine whether the boom angular acceleration command value exceeds a predetermined upper limit value (hereinafter, "boom angular acceleration upper limit value"). In this case, the limiting unit 3007 may calculate the boom angular acceleration command value based on, for example, the boom command value β generated in the current control cycle and the boom angle β calculated in each control cycle by the boom angle calculation unit 3009A 1r and the history of the boom angles β calculated in each control cycle by the boom angle calculation unit 3009A 1 for the past several times including the current and previous times. Further, the boom angular acceleration upper limit value may be defined in advance as the limit value of the angular acceleration that the boom 4 can output (or a value with a certain margin with respect to the limit value), which may vary depending on various parameters such as the boom angle, the operating direction of the boom 4, and the output of the engine 11. Further, in step S102, the limiting unit 3007 may obtain a measured value corresponding to the angular acceleration of the boom 4 (hereinafter, "boom angular acceleration measured value"), and in step S104, determine whether the boom angular acceleration measured value exceeds the boom angular acceleration upper limit value.

[0198] In step S106, the limiting unit 3007 obtains the boom angular velocity measured value (corresponding to the operation of the boom cylinder 7 as the second actuator).

[0199] In step S108, the restriction unit 3007 calculates the deviation between the boom angular velocity command value and the measured boom angular velocity (hereinafter referred to as "boom angular velocity deviation") corresponding to the deviation between the command value and the measured value of the boom cylinder 7 (as the second actuator).

[0200] In step S110, the restriction unit 3007 determines whether the boom angular velocity deviation (corresponding to the deviation between the command value and the measured value of the boom cylinder 7 as the second actuator) exceeds a predetermined threshold value.

[0201] The threshold value can be predefined, for example, as the limit value of the change range of the angular velocity of the boom 4 that can be changed within the control period under the constraints of the mechanism of the attachment or the like (or a value with a certain margin with respect to the limit value). And, similar to the case of the above-mentioned boom angular velocity upper limit value, the threshold value can vary according to the posture of the boom 4, that is, the boom angle, the operating direction of the boom 4 (whether it is the raising direction or the lowering direction), etc. Therefore, the restriction unit 3007 can calculate the threshold value by using a mechanical model of the attachment of the excavator 100 predefined based on the current boom angle, the operating direction of the boom 4, etc. Further, the restriction unit 3007 can also calculate the threshold value by using a map or the like that shows the relationship between the predefined threshold value and parameters such as the boom angle and the operating direction of the boom 4 based on the current boom angle, the operating direction of the boom 4, etc.

[0202] When the boom angular velocity deviation does not exceed the threshold value, the restriction unit 3007 determines that the operation of the boom 4 (boom cylinder 7) can be synchronized with the operation of the arm 5 (arm cylinder 8), and ends the current process. On the other hand, when the boom angular velocity deviation exceeds the threshold value, the restriction unit 3007 determines that the operation of the boom 4 (boom cylinder 7) may not be synchronized with the operation of the arm 5 (arm cylinder 8), and proceeds to step S112.

[0203] Still, in step S108, the restricting unit 3007 may calculate the deviation from the measured value regarding the angular acceleration of the boom 4 (hereinafter, “boom angular acceleration measured value”), and in step S110, determine whether the deviation between the angular acceleration command value of the boom 4 and the boom angular acceleration measured value exceeds a predetermined threshold value. At this time, similar to the case of the threshold value corresponding to the boom angular velocity deviation, the threshold value may be defined in advance as the limit value of the change range of the angular acceleration of the boom 4 that can be changed within the control period, which may vary depending on the boom angle, the operating direction of the boom 4, etc. (or a value with a certain margin with respect to the limit value).

[0204] In step S112, the restricting unit 3007 restricts the operation of the arm 5 (arm cylinder as the first actuator) and slows down the operation. Specifically, as described above, the restricting unit 3007 outputs a control command to the pressure reducing proportional valves 33AL, 33AR or the switching valve, and outputs the restriction command value Δβ 2r to the arm pilot command generation unit 3008B, and ends the processing in the current control period. Thereby, the controller 30 can slow down the actual operation of the arm 5 compared to the operation of the arm 5 corresponding to the operation content and operation command of the operator as described above.

[0205] Still, the series of processes of steps S102 and S104 described above and the series of processes of steps S106 to S110 may be processed in parallel.

[0206] [Operation] Next, with reference to FIGS. 8 (FIGS. 8A and 8B) and 9, the operation of the excavator 100 according to the present embodiment will be described.

[0207] Figures 8A, 8B, and 9 are diagrams for explaining the operation of the excavator 100 according to the present embodiment. Specifically, FIG. 8A is a diagram showing an example of the operation of the attachment AT by the machine control function of the excavator according to the comparative example, and FIG. 8B is a diagram showing an example of the operation of the attachment AT by the machine control function of the excavator 100 according to the present embodiment. FIG. 9 is a diagram showing another example of the operation of the attachment AT by the machine control function of the excavator 100 according to the present embodiment.

[0208] In the drawings, for convenience, only the portion of the attachment AT in the excavator 100 is shown, and the attachment AT of the excavator 100 is operating from the solid line state toward the dotted line state. Further, the excavator according to the comparative example omits at least the above-described limiting portion 3007 from the excavator 100 according to the present embodiment.

[0209] For example, depending on the operation mode (e.g., operation speed, etc.) of the arm 5 by the operator and the content of the operation command, the operation of the boom 4 necessary to move the tip of the bucket 6 along the target construction surface in accordance with the operation of the arm 5 may exceed the limit regarding the operation of the boom 4 (e.g., the upper limit values of angular velocity and angular acceleration).

[0210] In such a situation, in the case of the comparative example, as shown in FIG. 8A, the boom 4 cannot match (synchronize) its operation with the operation of the arm 5. As a result, the trajectory of the tip of the bucket 6 or the like exceeds the target construction surface SF (the dotted line trajectory in the figure). This is because the boom 4, which is a slave element, has a relatively larger mass (inertia) than the arm 5 or the like, which is a master element, and the operation is relatively slower. Therefore, the slave element, the arm 5, needs to match the operation of the master element, the boom 4.

[0211] In contrast, in the present embodiment, when the operation of the boom 4 cannot be synchronized with the operation of the arm 5 that operates according to the operation by the operator or the content of the operation command related to the autonomous driving function, or when there is a possibility that the synchronization cannot be achieved, the controller 30 controls (slows down) the operation of the arm 5 so as to correspond to the operation of the boom 4. In other words, when the operation of the boom cylinder 7 (an example of the second actuator) cannot be synchronized with the operation of the arm cylinder 8 (an example of the first actuator), or when there is a possibility that the synchronization cannot be achieved, the controller 30 controls the actual operation of the arm cylinder 8 to be slower than the operation assumed from the operation by the operator or the content (operation amount) of the operation command. Specifically, when a condition in which the operation of the boom cylinder 7 cannot be synchronized with the operation of the arm cylinder 8, or a condition in which it can be determined that there is a possibility that the synchronization cannot be achieved, that is, when the non-synchronization condition is satisfied, the controller 30 slows down the operation of the arm cylinder 8 corresponding to the operation or operation command regarding the arm 5 by the operator compared to the case where the non-synchronization condition is not satisfied. As a result, the speed (angular velocity) and acceleration (angular acceleration) related to the operation of the arm 5 are reduced compared to the speed (angular velocity) and acceleration (angular acceleration) corresponding to the operation or operation command regarding the arm 5 by the operator. Therefore, as shown in FIG. 8B, the boom 4 operates so that the tip of the bucket 6 moves along the target construction surface in accordance with the operation of the arm 5 corrected to be slower than the operation corresponding to the operation or operation command regarding the arm 5 by the operator. Therefore, the excavator 100 according to the present embodiment can move the tip of the attachment AT (for example, the working part such as the tip of the bucket 6) more appropriately along the target construction surface according to the operation by the operator or the operation command related to the autonomous driving function.

[0212] Also, for example, as shown in FIG. 9, when the slope of the target construction surface SF becomes relatively large, in order to move the tip of the bucket 6 along the target construction surface SF, it is necessary to increase the vertical movement amount of the bucket 6. That is, higher responsiveness is required for the operation of the boom 4 for moving the bucket 6 in the vertical direction than for the operation of the arm 5 for moving the bucket 6 in the horizontal direction. Therefore, in a situation where the slope of the target construction surface SF is relatively large, in accordance with the operation of the arm 5 corresponding to the content (operation amount) of the operation instruction regarding the operation of the arm 5 by the operator or the autonomous operation function, the operation of the boom 4 necessary to move the tip of the bucket 6 along the target construction surface is likely to exceed the limit regarding the operation of the boom 4. As a result, the operation of the attachment becomes jerky, and the excavator 100 (controller 30) may not be able to smoothly move the bucket 6 along the target construction surface SF.

[0213] On the other hand, in the present embodiment, as described above, when the operation of the boom 4 cannot be synchronized with the operation of the arm 5 that operates according to the content of the operation instruction regarding the operation of the arm 5 by the operator or the autonomous operation function, or when there is a possibility that they cannot be synchronized, the controller 30 slows down the operation of the arm 5. Therefore, the boom 4 (boom cylinder 7) can operate so that the tip of the bucket 6 moves along the target construction surface SF in accordance with the operation of the arm 5 (arm cylinder 8) that is corrected to be slower than the operation corresponding to the content (operation amount) of the operation instruction regarding the operation of the arm 5 (arm cylinder 8). Accordingly, even when the slope of the target construction surface SF is relatively large, the excavator 100 according to the present embodiment can more appropriately move the tip of the attachment AT (for example, the working part such as the tip of the bucket 6) along the target construction surface in response to the operation by the operator or the operation instruction regarding the autonomous operation function.

[0214] Further, regarding the operation of the bucket 6 (bucket cylinder 9), the controller 30 may determine whether a non-synchronizable condition is satisfied for the operation of the arm 5 corresponding to the operation of the arm 5 by the operator or the content of the operation command regarding the autonomous driving function, in the same manner as in the case of the operation of the boom 4 (boom cylinder 7). Then, when the operation of the bucket 6 becomes non-synchronized with the operation of the arm 5, or when a non-synchronizable condition that can be determined to potentially become non-synchronizable is established, the controller 30 may slow down the operation of the arm 5. That is, when the operation of the bucket cylinder 9 (an example of the second actuator) cannot be synchronized with the operation of the arm cylinder 8 (an example of the first actuator), or when there is a possibility that it cannot be synchronized, the controller 30 may slow down the operation of the arm cylinder 8 corresponding to the operation regarding the arm 5 or the operation command regarding the autonomous driving function.

[0215] [Excavator Management System] Next, with reference to FIG. 10, the excavator management system SYS will be described.

[0216] FIG. 10 is a schematic diagram showing an example of the excavator management system SYS.

[0217] As shown in FIG. 10, the excavator management system SYS includes an excavator 100, a support device 200, and a management device 300. The excavator management system SYS is a system for managing one or more excavators 100.

[0218] The information acquired by the excavator 100 may be shared with the administrator and the operators of other excavators, etc. through the excavator management system SYS. Each of the excavator 100, the support device 200, and the management device 300 constituting the excavator management system SYS may be one unit or a plurality of units. In this example, the excavator management system SYS includes one excavator 100, one support device 200, and one management device 300.

[0219] The support device 200 is typically a portable terminal device, such as a laptop computer terminal, a tablet terminal, or a smartphone, etc., carried by an operator at a construction site. The support device 200 may be a portable terminal carried by the operator of the excavator 100. The support device 200 may also be a fixed terminal device.

[0220] The management device 300 is typically a fixed terminal device, such as a server computer (so-called cloud server) installed in a management center outside the construction site. Further, the management device 300 may be, for example, an edge server set at the construction site. Also, the management device 300 may be a portable terminal device (for example, a portable terminal such as a laptop computer terminal, a tablet terminal, or a smartphone).

[0221] At least one of the support device 200 and the management device 300 may include a monitor and an operating device for remote operation. In this case, an operator using the support device 200 or the management device 300 may operate the excavator 100 while using the operating device for remote operation. The operating device for remote operation is communicably connected to the controller 30 mounted on the excavator 100 through a wireless communication network such as a short-range wireless communication network, a mobile phone communication network, or a satellite communication network.

[0222] Also, various information images (for example, image information representing the state around the excavator 100 and various setting screens) displayed on the display device D1 installed in the cab 10 may be displayed on a display device connected to at least one of the support device 200 and the management device 300. The image information representing the state around the excavator 100 may be generated based on the captured image of the space recognition device 70. Thereby, an operator using the support device 200 or a manager using the management device 300 can perform remote operation of the excavator 100 or perform various settings related to the excavator 100 while checking the state around the excavator 100.

[0223] For example, in the excavator management system SYS, the controller 30 of the excavator 100 may transmit information regarding the machine control function being executed to at least one of the support device 200 and the management device 300. At this time, the controller 30 may transmit at least one of the output of the space recognition device 70 and an image captured by a monocular camera, etc. to at least one of the support device 200 and the management device 300. The image may be a plurality of images captured during the execution of the machine control function. Further, the controller 30 may transmit information regarding at least one of data regarding the operation content of the excavator 100 during the execution of the machine control function, data regarding the posture of the excavator 100, and data regarding the posture of the excavation attachment, etc. to at least one of the support device 200 and the management device 300. This is to enable an operator using the support device 200 or an administrator using the management device 300 to obtain information regarding the excavator 100 during the execution of the machine control function.

[0224] In this way, the excavator management system SYS enables the information regarding the excavator 100 obtained during the execution of the machine control function to be shared with the administrator and the operators of other excavators, etc.

[0225] [Modifications and Changes] Although the embodiments have been described in detail above, the present disclosure is not limited to such specific embodiments, and various modifications and changes are possible within the scope of the gist described in the claims.

[0226] For example, in the above-described embodiment, the master element is the arm 5, and the slave elements are the boom 4 and the bucket 6. However, the master element may be the boom 4, and the slave elements may be the arm 5 and the bucket 6. In this case, when a synchronization impossible condition that the operation of at least one of the arm 5 and the bucket 6 becomes or may become out of synchronization with the operation of the boom 4, which can be determined by the controller 30 in the same manner as when the master element is the arm 5, is satisfied, the operation of the boom 4 may be slowed down. That is, when the operation of at least one of the arm cylinder 8 and the bucket cylinder 9 (both are examples of the second actuator) cannot be synchronized with the operation of the boom cylinder 7 (an example of the first actuator), or there is a possibility that the synchronization cannot be achieved, the controller 30 may slow down the operation of the boom cylinder 7 corresponding to the operation of the boom 4 by the operator.

[0227] In addition, in the above-described embodiments and modifications, the machine control function related to the operation of the attachment has been described in detail. However, in addition to the attachment, the machine control function may be applied to the operation of the excavator 100 including the upper swing body 3 and the lower traveling body 1. For example, during the boom raising and swinging operation of the excavator 100, the master control function may be applied to the combined operation of the upper swing body 3 (swing hydraulic motor) and the attachment. In this case, the controller 30 may control the proportional valves 31DL, 31DR and the pressure reducing proportional valves 33DL, 33DR in accordance with the operator's operation input or the operation command related to the autonomous driving function, thereby controlling the operation of the upper swing body 3 (swing hydraulic motor 2A) as the master element. Further, the controller 30 may control the proportional valves 31BL, 31BR and the pressure reducing proportional valves 33BL, 33BR to control the operation of the boom 4 (boom cylinder 7) etc. as the slave element in accordance with the operation of the upper swing body 3 (swing hydraulic motor 2A). On the other hand, when the non-synchronizable condition is satisfied, the controller 30 may limit the operation of the upper swing body 3 (swing hydraulic motor 2A) and control the operation of the upper swing body 3 (swing hydraulic motor 2A) so as to correspond to the operation of the boom 4 (boom cylinder 7). The non-synchronizable condition may be, for example, "the height of the bucket 6 from the ground is below a predetermined standard", and the predetermined standard may be variably set in such a manner that it increases as the swing angle from the start of the swing of the upper swing body 3 increases. Thereby, when the speed of the boom raising operation is relatively slow with respect to the swing operation of the upper swing body 3, the controller 30 can suppress a situation in which the bucket 6 comes into contact with the loading platform of the dump truck without ensuring a sufficient height of the bucket 6 from the ground.

[0228] In addition, in the above-described embodiments and modifications, the conditions regarding the angular velocities of the boom 4, arm 5, bucket 6, etc. are defined as the non-synchronizable conditions, but the present aspect is not limited thereto. For example, as the non-synchronizable conditions, instead of or in addition to the conditions regarding the angular velocities of the boom 4, arm 5, bucket 6, etc. as described above, the conditions regarding the state of the working part of the end attachment (for example, the tip or the back surface of the bucket 6) may be defined. Specifically, the non-synchronizable conditions regarding the vertical velocity of the working part of the end attachment with respect to the target construction surface may be defined.

[0229] In addition, in the above-described embodiments and modifications, the excavator 100 is configured to hydraulically drive all of the various operating elements such as the lower traveling body 1, upper swing body 3, boom 4, arm 5, and bucket 6, but a part thereof may be configured to be electrically driven. For example, instead of being hydraulically driven by the swing hydraulic motor 2A, the upper swing body 3 may be electrically driven by a swing electric motor (an example of a swing actuator). That is, the configurations disclosed in the above-described embodiments may be applied to a hybrid excavator, an electric excavator, or the like.

[0230] Finally, this application claims priority based on Japanese Patent Application No. 2018-214165 filed on November 14, 2018, and incorporates the entire contents of the Japanese patent application by reference.

Description of Reference Numerals

[0231] 1 Lower traveling body 2 Swing mechanism 3 Upper swing body 4 Boom 5 Arm 6 Bucket 7 Boom cylinder (second actuator) 8 Arm cylinder (first actuator) 9 Bucket cylinder 26 Operating device 26L Left operation lever 26R Right operation lever 29, 29AL, 29BL, 29CL Operating pressure sensor 30 Controller (control device) 31, 31AL, 31AR, 31BL, 31BR, 31CL, 31CR Proportional valve 32, 32AL, 32AR, 32BL, 32BR, 32CL, 32CR Shuttle valve 33, 33AL, 33AR, 33BL, 33BR, 33CL, 33CR Proportional valve for pressure reduction 100 Excavator AT Attachment S1 Boom angle sensor S2 Arm angle sensor S3 Bucket angle sensor S4 Machine body tilt sensor S5 Swing state sensor

Claims

1. A lower traveling body, an upper revolving body rotatably mounted on the lower traveling body, an attachment attached to the upper revolving body, a first actuator that operates according to an operation command by an operator's operation input or an autonomous driving function, and a second actuator different from the first actuator, the attachment and a plurality of actuators for driving the upper revolving body, a control device that controls the second actuator to automatically operate in accordance with the operation of the first actuator so that the tip of the attachment moves along a target trajectory, and is provided with the control device restricts the operation of the first actuator so as to correspond to the operation of the second actuator when it becomes impossible to synchronize the operation of the second actuator with the operation of the first actuator in a state where the tip of the attachment is moved along the target trajectory by controlling the operation of the second actuator in accordance with the operation of the first actuator, or when there is a possibility that synchronization cannot be achieved. An excavator.

2. The case where it becomes impossible to synchronize the operation of the second actuator with the operation of the first actuator, or the case where there is a possibility that synchronization cannot be achieved means that a predetermined condition including that a command value regarding the operation of the second actuator exceeds a predetermined upper limit value is satisfied. The excavator according to Claim 1.

3. The case where it becomes impossible to synchronize the operation of the second actuator with the operation of the first actuator, or the case where there is a possibility that synchronization cannot be achieved means that a predetermined condition including that a measured value regarding the operation of the second actuator exceeds a predetermined upper limit value is satisfied. The excavator according to Claim 1.

4. The case where it becomes impossible to synchronize the operation of the second actuator with the operation of the first actuator, or the case where there is a possibility that synchronization cannot be achieved means that a predetermined condition including that a deviation between a command value regarding the operation of the second actuator and a measured value regarding the operation of the second actuator corresponding to the command value exceeds a predetermined threshold value is satisfied. The excavator according to any one of claims 1 to 3.

5. When the control device is unable to synchronize the operation of the second actuator with the operation of the first actuator, or when there is a possibility of being unable to synchronize, the control device slows down the operation of the first actuator corresponding to the operation input or the operation command regarding the first actuator. The excavator according to any one of claims 1 to 4.

6. The control device generates a command value regarding the operation of the first actuator according to the operation amount of the operation input or the operation command, controls the first actuator based on the generated command value regarding the operation of the first actuator, and when the control device is unable to synchronize the operation of the second actuator with the operation of the first actuator, or when there is a possibility of being unable to synchronize, makes the magnitude of the command value regarding the operation of the first actuator with respect to the operation amount smaller than in the case where it can be synchronized. The excavator according to claim 5.

7. The attachment includes a boom, an arm, and a bucket. The plurality of actuators includes a boom cylinder that drives the boom, an arm cylinder that drives the arm, and a bucket cylinder that drives the bucket. During the excavation operation, when the control device is unable to synchronize the operation of at least one of the boom cylinder and the bucket cylinder, which are the second actuators, with the operation of the arm cylinder, which is the first actuator, or when there is a possibility of being unable to synchronize, while controlling at least one of the boom cylinder and the bucket cylinder in accordance with the operation of the arm cylinder, the control device restricts the operation of the arm cylinder so as to correspond to the operation of at least one of the boom cylinder and the bucket cylinder. The excavator according to any one of claims 1 to 6.

8. The plurality of actuators includes a boom cylinder that drives the boom included in the attachment, and a swing actuator that drives the upper swing body. When the control device controls the operation of the boom cylinder as the second actuator in accordance with the operation of the slewing actuator as the first actuator during the boom raising and slewing operation, and it becomes impossible to synchronize the operation of the boom cylinder with the operation of the slewing actuator, or there is a possibility that synchronization cannot be achieved, the control device restricts the operation of the slewing actuator so as to correspond to the operation of the boom cylinder. The excavator according to any one of claims 1 to 6.

9. Comprising a space recognition device for recognizing the state around the excavator. Before the operation of the actuator starts, when it is determined based on the acquired information of the space recognition device that there is a person within a predetermined range from the excavator, the control device makes the actuator inoperable. The excavator according to any one of claims 1 to 8.

10. A space recognition device for recognizing the state around the excavator, And an operation device for receiving an operation of the actuator. Before the operation of the actuator starts, when it is determined based on the acquired information of the space recognition device that there is a person within a predetermined range from the excavator, the control device does not drive the actuator even if the operation device is operated. The excavator according to any one of claims 1 to 8.

11. A control device for an excavator, including a lower traveling body, an upper slewing body rotatably mounted on the lower traveling body, an attachment attached to the upper slewing body, a first actuator that operates according to an operation input of an operator or an operation command by an autonomous driving function, and a second actuator different from the first actuator, and including a plurality of actuators for driving the attachment and the upper slewing body. By controlling the second actuator to automatically operate in accordance with the operation of the first actuator, the tip of the attachment is operated along a target trajectory. When it becomes impossible to synchronize the operation of the second actuator with the operation of the first actuator so that the tip of the attachment moves along the target trajectory while controlling the operation of the second actuator in accordance with the operation of the first actuator, or when there is a possibility that synchronization becomes impossible, the operation of the first actuator is restricted so as to correspond to the operation of the second actuator. Control device for a hydraulic excavator.

Images