Work machine and remote control system for work machine

Abstract

A work machine according to one embodiment of the present invention comprises: a lower traveling body; an upper turning body turnably mounted on the lower traveling body; an attachment attached to the upper turning body; a work tool provided at a tip of the attachment; a storage unit for storing reference surface information indicating a shape of a surface after construction; and a control device configured so as to perform control for moving the work tool along an area in which the surface represented by the reference surface information is extended.

Description

Work machine and work machine remote control system

[0001] The present invention relates to a work machine and a remote control system for the work machine.

[0002]

[0003] Conventionally, there has been known a work machine that controls a predetermined portion of a work implement to move along a design surface when an operation is received from an operator. For example, a technology has been proposed that switches between a normal control mode and a low-speed control mode when moving a predetermined portion along a design surface in accordance with the angle at the boundary between two design surfaces (see, for example, Patent Document 1).

[0003] International Publication No. 2019 / 189624

[0004] Incidentally, when working on multiple surfaces, conventional work machines have a function of moving the work tool so that it comes into contact with one of the multiple surfaces depending on the position of the work tool. Therefore, when working on one of the multiple surfaces, if the work tool is also close to another surface, the work tool may be controlled to move so that it comes into contact with the other surface regardless of the operator's intention. Therefore, with work machines that have a function to move the work tool, it may be difficult to align the work tool with the desired surface when working on the surface.

[0005] One aspect of the present invention provides a technique for improving operability when performing construction work using a work tool.

[0006] A shovel according to one aspect of the present invention comprises a lower running body, an upper rotating body mounted on the lower running body so as to be freely rotatable, an attachment attached to the upper rotating body, a working tool provided at the tip of the attachment, a memory unit that stores reference surface information representing the shape of the surface after construction, and a control device configured to control the movement of the working tool along an area extending from the surface represented by the reference surface information.

[0007] According to one aspect of the present invention, operability when performing construction work using a work tool is improved.

[0008] FIG. 1 is a side view of a shovel according to the first embodiment. FIG. 2 is a diagram showing an example of the configuration of a drive control system of the shovel according to the first embodiment. FIG. 3 is a diagram showing an example of the configuration of a hydraulic system mounted on the shovel according to the first embodiment. FIG. 4 is a conceptual diagram showing an example of a target construction surface on which the shovel according to the first embodiment will perform construction. FIG. 5 is a diagram showing a movement trajectory of a bucket when a conventional machine control function is executed with respect to the target construction surface. FIG. 6 is a diagram showing a guide surface set by control of the machine control function unit according to the first embodiment and movement of the bucket along the guide surface. FIG. 7 is a diagram showing transitions of screens displayed until the guide surface is set in the machine control function unit according to the first embodiment. FIG. 8 is a diagram showing a guide surface set by control of the machine control function unit according to the first embodiment and movement of the bucket along the guide surface. FIG. 9 is a diagram showing a guide surface set by control of the machine control function unit according to the first embodiment. FIG. 10 is a flowchart showing a processing procedure executed by the machine control function unit according to the first embodiment. FIG. 11 is an explanatory diagram showing a control procedure by the machine control function unit according to a modified example of the first embodiment. FIG. 12 is a schematic diagram showing an example of a remote operation system according to a second embodiment.

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments described below are merely examples and do not limit the invention, and all features and combinations described in the embodiments are not necessarily essential to the invention. In addition, identical or corresponding components in each drawing are designated by identical or corresponding reference numerals, and descriptions thereof may be omitted.

[0010] In the following embodiments of the present invention, an example will be described in which a shovel is used as an example of a work machine, but the present invention is not limited to a shovel. The present invention may be applied to construction machines, standard machines, application machines, forestry machines, or conveyance machines based on hydraulic shovels.

[0011] First Embodiment An outline of a shovel 100 according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a side view of the shovel 100 as a work machine according to this embodiment.

[0012] The excavator 100 according to this embodiment comprises a lower running body 1, an upper rotating body 3 mounted on the lower running body 1 so as to be freely rotatable via a rotating mechanism 2, a boom 4, an arm 5, and a bucket 6 constituting an attachment (working machine), and a cabin 10.

[0013] The lower traveling body 1 has a pair of left and right crawlers that are hydraulically driven by hydraulic traveling motors 2ML, 2MR (see FIG. 2 described later), thereby causing the excavator 100 to travel. In other words, the pair of hydraulic traveling motors 2ML, 2MR (an example of a traveling motor) drive the lower traveling body 1 (crawlers) as a driven part.

[0014] The upper rotating body 3 is driven by a swing hydraulic motor 2A (see FIG. 2 described later) to swing relative to the lower traveling body 1. In other words, the swing hydraulic motor 2A is a swing driving part that drives the upper rotating body 3 as a driven part, and can change the orientation of the upper rotating body 3.

[0015] The upper rotating body 3 may be electrically driven by an electric motor (hereinafter referred to as "swing electric motor") instead of the swing hydraulic motor 2A. In other words, the swing electric motor is a swing drive unit that drives the upper rotating body 3 as a non-drive unit, similar to the swing hydraulic motor 2A, and can change the orientation of the upper rotating body 3.

[0016] The boom 4 is pivotally mounted to the front center of the upper rotating body 3 so as to be able to tilt up and down, an arm 5 is pivotally mounted to the tip of the boom 4 so as to be able to rotate up and down, and a bucket 6 serving as an end attachment is pivotally mounted to the tip of the arm 5 so as to be able to rotate up and down. The boom 4, arm 5, and bucket 6 are hydraulically driven by a boom cylinder 7, an arm cylinder 8, and a bucket cylinder 9, each of which serves as a hydraulic actuator.

[0017] The bucket 6 is an example of an end attachment (work tool) provided at the tip of the arm 5, and is specifically an excavation bucket, but may also be a skeleton bucket or a gravel removal bucket. The bucket 6 may also be equipped with a bucket tilt mechanism.

[0018] The upper rotating body 3 is provided with a cabin 10 as a driver's cab and is equipped with a power source such as an engine 11. An operation device 26, a controller 30, etc. are provided inside the cabin 10. In addition, an imaging device S6, etc. are attached to the upper rotating body 3.

[0019] The imaging device S6 captures images of the periphery of the shovel 100. The imaging device S6 includes a camera S6F that captures images in front of the shovel 100, a camera S6L that captures images to the left of the shovel 100, a camera S6R that captures images to the right of the shovel 100, and a camera S6B that captures images behind the shovel 100.

[0020] Camera S6F is attached, for example, to the ceiling of the cabin 10, i.e., inside the cabin 10. Camera S6F may also be attached to the exterior of the cabin 10, such as on the roof of the cabin 10 or on the side of the boom 4. Camera S6L is attached to the left end of the upper surface of the upper rotating body 3, camera S6R is attached to the right end of the upper surface of the upper rotating body 3, and camera S6B is attached to the rear end of the upper surface of the upper rotating body 3.

[0021] The image capturing device S6 (cameras S6F, S6B, S6L, and S6R) is, for example, a single-lens wide-angle camera having a very wide angle of view. The image capturing device S6 may also be a stereo camera or a distance imaging camera. Images captured by the image capturing device S6 are input to the controller 30.

[0022] The imaging device S6 serving as a spatial recognition device may function as an object detection device. In this case, the imaging device S6 may detect objects present around the shovel 100. Objects to be detected may include, for example, people, animals, vehicles, construction machinery, buildings, holes, etc. Furthermore, the imaging device S6 may calculate the distance from the imaging device S6 or the shovel 100 to the recognized object. The imaging device S6 serving as an object detection device may include, for example, a stereo camera, a distance image sensor, etc. Furthermore, the spatial recognition device is, for example, a monocular camera having an imaging element such as a CCD or a CMOS, and outputs the captured image to the display device 60. Furthermore, the spatial recognition device may be configured to calculate the distance from the spatial recognition device or the shovel 100 to the recognized object. Furthermore, in addition to the imaging device S6, other object detection devices such as an ultrasonic sensor, millimeter-wave radar, LIDAR, or infrared sensor may be provided as the spatial recognition device. When a millimeter wave radar, ultrasonic sensor, laser radar, or the like is used as a spatial recognition device, a number of signals (laser light, etc.) may be emitted to an object, and the reflected signals may be received, and the distance and direction of the object may be detected from the reflected signals.

[0023] The operating device 26 is a device used by an operator to operate the actuator. The operating device 26 includes, for example, an operating lever and an operating pedal. The actuator includes at least one of a hydraulic actuator and an electric actuator.

[0024] The input device 62 is provided within reach of an operator seated in the cabin 10, accepts various operational inputs from the operator, and outputs signals corresponding to the operational inputs to the controller 30. The input device 62 includes a touch panel or the like mounted on the display of the display device 60 that displays various information images. A signal corresponding to the content of an operation on the input device 62 is taken in by the controller 30.

[0025] The display device 60 is provided in a location that is easily visible to an operator seated in the cabin 10, and displays various information images under the control of the controller 30. The display device 60 may be connected to the controller 30 via an in-vehicle communication network such as a Controller Area Network (CAN), or may be connected to the controller 30 via a one-to-one dedicated line.

[0026] The communication device T1 communicates with external devices through a predetermined network including a mobile communication network with a base station as an end, a satellite communication network, the Internet, etc. The communication device T1 is, for example, a mobile communication module compatible with mobile communication standards such as LTE (Long Term Evolution), 4G (4th Generation), and 5G (5th Generation), or a satellite communication module for connecting to a satellite communication network.

[0027] The controller (control device) 30 is a control device for controlling the shovel 100. For example, the controller 30 is mainly configured with a computer including a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), a non-volatile auxiliary storage device, various input / output interfaces, etc. The controller 30 then reads programs from the non-volatile storage device, loads them into a volatile storage device, and has the CPU execute the programs to realize various functions. The various functions include, for example, a machine guidance function that guides the operator in manually operating the shovel 100. The controller 30 may also include a contact avoidance function that automatically or autonomously operates or stops the shovel 100 to avoid contact between the shovel 100 and an object present within a monitoring range around the shovel 100.

[0028] For example, the controller 30 sets a target rotation speed based on an operation by an operator or the like, and performs drive control to rotate the engine 11 at a constant speed.

[0029] Furthermore, the controller 30 includes, for example, a machine control function unit 50 having a function of automatically assisting the operator in manually operating the shovel 100 through the operating device 26. The machine control function unit 50 will be described later.

[0030] Note that some of the functions of the controller 30 may be realized by another controller (control device). That is, the functions of the controller 30 may be realized in a distributed manner by a plurality of controllers. For example, the machine guidance function and the machine control function unit 50 may be realized by a dedicated controller (control device).

[0031] The boom angle sensor S1 is attached to the boom 4 and detects the elevation / depression angle of the boom 4 relative to the upper rotating unit 3 (hereinafter referred to as the "boom angle"), for example, the angle formed by a line connecting the fulcrums at both ends of the boom 4 relative to the rotation plane of the upper rotating unit 3 in a side view. The boom angle sensor S1 may include, for example, a rotary encoder, an acceleration sensor, a six-axis sensor, an IMU (Inertial Measurement Unit), etc. The boom angle sensor S1 may also include a potentiometer using a variable resistor, a cylinder stroke sensor that detects the stroke amount of a hydraulic cylinder (boom cylinder 7) corresponding to the boom angle, etc. The same applies to the arm angle sensor S2 and the bucket angle sensor S3 below. A detection signal corresponding to the boom angle detected by the boom angle sensor S1 is input to the controller 30.

[0032] The arm angle sensor S2 is attached to the arm 5 and detects the rotation angle of the arm 5 relative to the boom 4 (hereinafter referred to as the "arm angle"), for example, the angle formed by a line connecting the fulcrums at both ends of the arm 5 with a line connecting the fulcrums at both ends of the boom 4 in a side view. A detection signal corresponding to the arm angle detected by the arm angle sensor S2 is input to the controller 30.

[0033] Bucket angle sensor S3 is attached to bucket 6 and detects the rotation angle of bucket 6 relative to arm 5 (hereinafter referred to as "bucket angle"), for example, the angle, in a side view, formed by a line connecting the fulcrum of bucket 6 and its tip (toe) with respect to a line connecting the fulcrums at both ends of arm 5. A detection signal corresponding to the bucket angle from bucket angle sensor S3 is input to controller 30.

[0034] The machine body tilt sensor S4 (an example of an attitude detection unit) detects the tilt state of the machine body (the upper rotating body 3 or the lower running body 1) with respect to a horizontal plane. The machine body tilt sensor S4 is attached to, for example, the upper rotating body 3, and detects the tilt angles of the excavator 100 (i.e., the upper rotating body 3) about two axes in the fore-aft and lateral directions (hereinafter referred to as the "fore-aft tilt angle" and the "lateral tilt angle"). The machine body tilt sensor S4 may include, for example, a rotary encoder, an acceleration sensor, a six-axis sensor, an IMU, etc. Detection signals corresponding to the tilt angles (fore-aft tilt angle and lateral tilt angle) by the machine body tilt sensor S4 are input to the controller 30.

[0035] The swing angle sensor S5 outputs detection information related to the swing state of the upper swing body 3. The swing angle sensor S5 detects, for example, the swing angular velocity and swing angle of the upper swing body 3. The swing angle sensor S5 may include, for example, a gyro sensor, a resolver, a rotary encoder, etc. The detection signals corresponding to the swing angle and swing angular velocity of the upper swing body 3 detected by the swing angle sensor S5 are input to the controller 30.

[0036] A boom rod pressure sensor S7R and a boom bottom pressure sensor S7B are attached to the boom cylinder 7. An arm rod pressure sensor S8R and an arm bottom pressure sensor S8B are attached to the arm cylinder 8. A bucket rod pressure sensor S9R and a bucket bottom pressure sensor S9B are attached to the bucket cylinder 9. The boom rod pressure sensor S7R, boom bottom pressure sensor S7B, arm rod pressure sensor S8R, arm bottom pressure sensor S8B, bucket rod pressure sensor S9R, and bucket bottom pressure sensor S9B are collectively referred to as "cylinder pressure sensors."

[0037] The boom rod pressure sensor S7R detects the pressure in the rod-side oil chamber of the boom cylinder 7 (hereinafter referred to as the "boom rod pressure"), and the boom bottom pressure sensor S7B detects the pressure in the bottom-side oil chamber of the boom cylinder 7 (hereinafter referred to as the "boom bottom pressure"). The arm rod pressure sensor S8R detects the pressure in the rod-side oil chamber of the arm cylinder 8 (hereinafter referred to as the "arm rod pressure"), and the arm bottom pressure sensor S8B detects the pressure in the bottom-side oil chamber of the arm cylinder 8 (hereinafter referred to as the "arm bottom pressure"). The bucket rod pressure sensor S9R detects the pressure in the rod-side oil chamber of the bucket cylinder 9 (hereinafter referred to as the "bucket rod pressure"), and the bucket bottom pressure sensor S9B detects the pressure in the bottom-side oil chamber of the bucket cylinder 9 (hereinafter referred to as the "bucket bottom pressure").

[0038] The positioning device PS measures the position and orientation of the upper rotating body 3. The positioning device PS is, for example, a Global Navigation Satellite System (GNSS) compass, and detects the position and orientation of the upper rotating body 3, and a detection signal corresponding to the position and orientation of the upper rotating body 3 is input into the controller 30. Furthermore, among the functions of the positioning device PS, the function of detecting the orientation of the upper rotating body 3 may be substituted by a direction sensor attached to the upper rotating body 3.

[0039] [Drive control system of shovel] Figure 2 is a diagram showing an example of the configuration of the drive control system of the shovel 100 of Figure 1. In Figure 2, the mechanical power transmission system is indicated by double lines, the hydraulic oil lines are indicated by thick solid lines, the pilot lines are indicated by dashed lines, and the electric drive and control system is indicated by dotted lines.

[0040] The drive system of the excavator 100 according to this embodiment includes the engine 11, the regulator 13, the main pump 14, and the control valve unit 17. As described above, the hydraulic drive system of the excavator 100 according to this embodiment includes hydraulic actuators such as the traveling hydraulic motors 2ML, 2MR, the swing hydraulic motor 2A, the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9, which hydraulically drive the lower traveling structure 1, the upper rotating structure 3, the boom 4, the arm 5, and the bucket 6, respectively. These hydraulic actuators are driven by hydraulic oil discharged from the main pump 14.

[0041] The engine 11 is the main power source in the hydraulic drive system and is mounted, for example, on the rear of the upper rotating body 3. Specifically, the engine 11 rotates at a constant speed at a preset target speed under direct or indirect control by a controller 30 (described later), and drives the main pump 14 and the pilot pump 15. The engine 11 is, for example, a diesel engine that uses diesel as fuel.

[0042] 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, for example, regulators 13L and 13R, as described below.

[0043] The main pump 14 is mounted on the rear of the upper rotating body 3, for example, similar to the engine 11, and supplies hydraulic oil to the control valve unit 17 through a high-pressure hydraulic line. As described above, the main pump 14 is driven by the engine 11. The main pump 14 is, for example, a variable displacement hydraulic pump, and as described above, under the control of the controller 30, the tilt angle of the swash plate is adjusted by the regulator 13, thereby adjusting the stroke length of the piston and controlling the discharge flow rate (discharge pressure). The main pump 14 includes, for example, main pumps 14L and 14R, as described below.

[0044] The control valve unit 17 is a hydraulic control device that controls the hydraulic system in the excavator 100. In this embodiment, the control valve unit 17 includes control valves 171 to 176. The control valve unit 17 is configured to selectively supply the hydraulic oil discharged by the main pump 14 to one or more hydraulic actuators through the control valves 171 to 176.

[0045] The control valves 171 to 176 control the flow rate of hydraulic oil flowing from the main pump 14 to the hydraulic actuators and the flow rate of hydraulic oil flowing from the hydraulic actuators to the hydraulic oil tank. The hydraulic actuators include the boom cylinder 7, arm cylinder 8, bucket cylinder 9, travel hydraulic motors 2ML and 2MR, and swing hydraulic motor 2A. More specifically, control valve 171 corresponds to the left travel hydraulic motor 2ML, control valve 172 corresponds to the right travel hydraulic motor 2MR, and control valve 173 corresponds to the swing hydraulic motor 2A. Furthermore, control valve 174 corresponds to the bucket cylinder 9, control valve 175 corresponds to the boom cylinder 7, and control valve 176 corresponds to the arm cylinder 8.

[0046] The pilot pump 15 is an example of a pilot pressure generating device, and is configured to supply hydraulic oil to the hydraulic control device via a pilot line. In this embodiment, the pilot pump 15 is a fixed displacement hydraulic pump. However, the pilot pressure generating device may be realized by the main pump 14. That is, the main pump 14 may have a function of supplying hydraulic oil to various hydraulic control devices via a pilot line, in addition to a function of supplying hydraulic oil to the control valve unit 17 via a hydraulic oil line. In this case, the pilot pump 15 may be omitted.

[0047] The operating device 26 is an example of an electric operating device that an operator uses to operate the actuator. The actuator includes at least one of a hydraulic actuator and an electric actuator.

[0048] The discharge pressure sensor 28 is configured to detect the discharge pressure of the main pump 14. In this embodiment, the discharge pressure sensor 28 outputs the detected value to the controller 30.

[0049] The operation sensor 29 is configured to detect the operation content of the operator using the operation device 26. In this embodiment, the operation sensor 29 detects the operation direction and operation amount of the operation device 26 corresponding to each actuator and outputs the detected value to the controller 30. In this embodiment, the controller 30 controls the opening area of ​​the proportional valve 31 in accordance with the output of the operation sensor 29. The controller 30 then supplies the hydraulic oil discharged from the pilot pump 15 to the pilot ports of the corresponding control valves in the control valve unit 17. The pressure of the hydraulic oil supplied to each pilot port (pilot pressure) is, in principle, a pressure corresponding to the operation direction and operation amount of the operation device 26 corresponding to each hydraulic actuator. In this way, the operation device 26 is configured to supply the hydraulic oil discharged from the pilot pump 15 to the pilot ports of the corresponding control valves in the control valve unit 17.

[0050] The proportional valve 31, which functions as a control valve for machine control, is disposed in a pipe connecting the pilot pump 15 and the pilot port of the control valve in the control valve unit 17, and is configured so that the flow path area of ​​the pipe can be changed. In this embodiment, the proportional valve 31 operates in response to a control command output by the controller 30.

[0051] The controller 30 is configured to control the opening and closing of the proportional valve 31 in accordance with a signal input from the operation sensor 29, so that the hydraulic oil discharged by the pilot pump 15 can be supplied via a pilot line to the pilot ports of the corresponding control valves 171 to 176 in the control valve unit 17. When the operator operates the operation device 26, the pressure of the hydraulic oil supplied to each pilot port (pilot pressure) is a pressure that corresponds to the operation direction and operation amount of the operation device 26 corresponding to each hydraulic actuator. In other words, the proportional valve 31 adjusts the pilot pressure supplied to the pilot ports of the control valves 171 to 176 based on the signal received from the operation sensor 29, in order to switch the supply paths of the control valves 171 to 176.

[0052] The controller 30 can apply the pilot pressure generated by the proportional valve 31 to the pilot port of the corresponding control valve. Therefore, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the pilot port of the control valve in the control valve unit 17 via the proportional valve 31, regardless of the operation of the operating device 26 by the operator.

[0053] With this configuration, the controller 30 can operate the hydraulic actuator corresponding to a specific operating device 26 even when no operation is being performed on that specific operating device 26. Furthermore, the controller 30 can forcibly stop the operation of the hydraulic actuator corresponding to that specific operating device 26 even when an operation is being performed on that specific operating device 26.

[0054] For example, when the controller 30 is configured to perform autonomous control of the shovel 100, it sets one or more of the target rotation angle for the upper rotating body 3, the target angles for each of the upper rotating body 3, the boom 4, the arm 5, and the bucket 6, and the target rotation speed for the engine 11 based on the operations performed by the autonomous control, and controls the operation of various components of the shovel 100.

[0055] Furthermore, for example, the controller 30 outputs a control command to the regulator 13 as necessary to change the discharge rate of the main pump 14 .

[0056] [Hydraulic System of Excavator] Next, a configuration example of a hydraulic system mounted on the excavator 100 will be described with reference to Fig. 3. Fig. 3 is a diagram showing a configuration example of a hydraulic system mounted on the excavator 100. In Fig. 3, a mechanical power transmission system, a hydraulic oil line, a pilot line, and an electrical control system are indicated by double lines, solid lines, dashed lines, and dotted lines, respectively.

[0057] The hydraulic system of the excavator 100 mainly includes an engine 11, a regulator 13, a main pump 14, a pilot pump 15, a control valve unit 17, an operating device 26, a discharge pressure sensor 28, an operating sensor 29, and a controller 30.

[0058] In FIG. 3, the hydraulic system is configured to circulate hydraulic oil from a main pump 14 driven by an engine 11 through a center bypass line 40 or a parallel line 42 to a hydraulic oil tank.

[0059] The main pump (hydraulic pump) 14 is configured to supply hydraulic oil via a hydraulic oil line to the control valve unit 17. In this embodiment, the main pump 14 is a swash plate type variable displacement hydraulic pump.

[0060] In this embodiment, the control valve unit 17 includes control valves 171 to 176. The control valve 175 includes a control valve 175L and a control valve 175R, and the control valve 176 includes a control valve 176L and a control valve 176R. The control valve unit 17 is configured to selectively supply the hydraulic oil discharged by the main pump 14 to one or more hydraulic actuators through the control valves 171 to 176.

[0061] The main pump 14 includes a left main pump 14L and a right main pump 14R. The left main pump 14L circulates hydraulic oil to the hydraulic oil tank via a left center bypass line 40L or a left parallel line 42L, and the right main pump 14R circulates hydraulic oil to the hydraulic oil tank via a right center bypass line 40R or a right parallel line 42R.

[0062] The left center bypass line 40L is a hydraulic oil line that passes through control valves 171, 173, 175L, and 176L arranged in the control valve unit 17. The right center bypass line 40R is a hydraulic oil line that passes through control valves 172, 174, 175R, and 176R arranged in the control valve unit 17.

[0063] The control valve 171 is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the left main pump 14L to the left traveling hydraulic motor 2ML and to discharge the hydraulic oil discharged by the left traveling hydraulic motor 2ML to the hydraulic oil tank.

[0064] The control valve 172 is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the right main pump 14R to the right traveling hydraulic motor 2MR and to discharge the hydraulic oil discharged by the right traveling hydraulic motor 2MR to the hydraulic oil tank.

[0065] The control valve 173 is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the left main pump 14L to the swing hydraulic motor 2A and to discharge the hydraulic oil discharged by the swing hydraulic motor 2A to the hydraulic oil tank.

[0066] The control valve 174 is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the right main pump 14R to the bucket cylinder 9 and to discharge the hydraulic oil in the bucket cylinder 9 to the hydraulic oil tank.

[0067] Control valve 175L is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by left main pump 14L to boom cylinder 7. Control valve 175R is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by right main pump 14R to boom cylinder 7 and to discharge the hydraulic oil in boom cylinder 7 to the hydraulic oil tank.

[0068] The control valve 176L is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the left main pump 14L to the arm cylinder 8 and to discharge the hydraulic oil in the arm cylinder 8 to the hydraulic oil tank.

[0069] The control valve 176R is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the right main pump 14R to the arm cylinder 8 and to discharge the hydraulic oil in the arm cylinder 8 to the hydraulic oil tank.

[0070] The left parallel conduit 42L is a hydraulic oil line that runs parallel to the left center bypass conduit 40L. The left parallel conduit 42L can supply hydraulic oil to a downstream control valve when the flow of hydraulic oil through the left center bypass conduit 40L is restricted or blocked by any of the control valves 171, 173, and 175L. The right parallel conduit 42R is a hydraulic oil line that runs parallel to the right center bypass conduit 40R. The right parallel conduit 42R can supply hydraulic oil to a downstream control valve when the flow of hydraulic oil through the right center bypass conduit 40R is restricted or blocked by any of the control valves 172, 174, and 175R.

[0071] As described above, the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9 are each provided with a cylinder pressure sensor.

[0072] Furthermore, a left turning pressure sensor S10L and a right turning pressure sensor S10R are attached to the swing hydraulic motor 2A. The left turning pressure sensor S10L detects the pressure of the hydraulic oil at the left port of the swing hydraulic motor 2A. The right turning pressure sensor S10R detects the pressure of the hydraulic oil at the right port of the swing hydraulic motor 2A.

[0073] The regulator 13 includes a left regulator 13L and a right regulator 13R. The left regulator 13L controls the discharge rate of the left main pump 14L by adjusting the tilt angle of the swash plate of the left main pump 14L in accordance with the discharge pressure of the left main pump 14L. Specifically, the left regulator 13L adjusts the tilt angle of the swash plate of the left main pump 14L in accordance with an increase in the discharge pressure of the left main pump 14L to reduce the discharge rate. The same applies to the right regulator 13R. This is to prevent the absorption power (absorption horsepower) of the main pump 14, which is expressed as the product of the discharge pressure and the discharge rate, from exceeding the output power (output horsepower) of the engine 11.

[0074] The operating device 26 includes a left operating lever 26L, a right operating lever 26R, and a travel lever 26D. The travel lever 26D includes a left traveling lever 26DL and a right traveling lever 26DR.

[0075] The operation sensor 29 includes operation sensors 29LA, 29LB, 29RA, 29RB, 29DL, and 29DR.

[0076] The left operating lever 26L is used for swing operation and operation of the arm 5. When the left operating lever 26L is operated in the forward / backward direction, it uses the hydraulic oil discharged by the pilot pump 15 to introduce a control pressure corresponding to the amount of lever operation into the pilot port of the control valve 176. When it is operated in the left / right direction, it uses the hydraulic oil discharged by the pilot pump 15 to introduce a control pressure corresponding to the amount of lever operation into the pilot port of the control valve 173.

[0077] The operation sensor 29LA detects the operation of the left operation lever 26L in the forward and backward directions by the operator, and outputs the detected value to the controller 30.

[0078] The operation sensor 29LB detects the operation of the left operation lever 26L in the left or right direction by the operator, and outputs the detected value to the controller 30.

[0079] When the left operating lever 26L is operated in the arm closing direction, the controller 30 controls the proportional valve 31 in accordance with a signal from the operation sensor 29LA to introduce hydraulic oil into the right pilot port of the control valve 176L and to introduce hydraulic oil into the left pilot port of the control valve 176R. On the other hand, when the left operating lever 26L is operated in the arm opening direction, the controller 30 controls the proportional valve 31 in accordance with a signal from the operation sensor 29LA to introduce hydraulic oil into the left pilot port of the control valve 176L and to introduce hydraulic oil into the right pilot port of the control valve 176R.

[0080] In addition, when the left operating lever 26L is operated in the left turning direction, the controller 30 controls the proportional valve 31 in accordance with a signal from the operation sensor 29LB to introduce hydraulic oil into the left pilot port of the control valve 173, and when the left operating lever 26L is operated in the right turning direction, the controller 30 controls the proportional valve 31 in accordance with a signal from the operation sensor 29LB to introduce hydraulic oil into the right pilot port of the control valve 173.

[0081] The left operating lever 26L is also provided with a switch NS. In this embodiment, the switch NS is 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. The switch NS may be provided on the right operating lever 26R or at another position within the cabin 10.

[0082] The right operating lever 26R is used to operate the boom 4 and the bucket 6. When the right operating lever 26R is operated in the forward / backward direction, it uses the hydraulic oil discharged by the pilot pump 15 to introduce a control pressure corresponding to the amount of lever operation into the pilot port of the control valve 175. When it is operated in the left / right direction, it uses the hydraulic oil discharged by the pilot pump 15 to introduce a control pressure corresponding to the amount of lever operation into the pilot port of the control valve 174.

[0083] The operation sensor 29RA detects the operation of the right operating lever 26R in the forward and backward directions by the operator, and outputs the detected value to the controller 30.

[0084] The operation sensor 29RB detects the operation of the right operating lever 26R in the left and right directions by the operator, and outputs the detected value to the controller 30.

[0085] Specifically, when the right operating lever 26R is operated in the boom-lowering direction, the controller 30 controls the proportional valve 31 in accordance with a signal from the operation sensor 29RA to introduce hydraulic oil into the left pilot port of the control valve 175L and to introduce hydraulic oil into the right pilot port of the control valve 175R. On the other hand, when the right operating lever 26R is operated in the boom-raising direction, the controller 30 controls the proportional valve 31 in accordance with a signal from the operation sensor 29RA to introduce hydraulic oil into the right pilot port of the control valve 175L and to introduce hydraulic oil into the left pilot port of the control valve 175R.

[0086] Furthermore, when the right operating lever 26R is operated in the bucket closing direction, the controller 30 controls the proportional valve 31 in accordance with a signal from the operation sensor 29RB to introduce hydraulic oil into the right pilot port of the control valve 174, and when the right operating lever 26R is operated in the bucket opening direction, the controller 30 controls the proportional valve 31 in accordance with a signal from the operation sensor 29RB to introduce hydraulic oil into the left pilot port of the control valve 174.

[0087] The travel lever 26D is used to operate the crawlers. Specifically, the left travel lever 26DL is used to operate the left crawler. It may be configured to be interlocked with the left travel pedal.

[0088] The operation sensor 29 DL detects the operation of the left travel lever 26 DL in the forward / backward direction by the operator, and outputs the detected value to the controller 30 .

[0089] When the left travel lever 26DL is operated in the forward / backward direction, the controller 30 controls the proportional valve 31 in accordance with a signal from the operation sensor 29DL, and uses the hydraulic oil discharged from the pilot pump 15 to introduce a control pressure corresponding to the amount of lever operation into the pilot port of the control valve 171.

[0090] The right travel lever 26DR is used to operate the right crawler and may be configured to operate in conjunction with the right travel pedal.

[0091] The operation sensor 29DR detects the operation of the right travel lever 26DR in the forward / backward direction by the operator, and outputs the detected value to the controller 30.

[0092] When the right travel lever 26DR is operated in the forward / backward direction, the controller 30 controls the proportional valve 31 in accordance with a signal from the operation sensor 29DR, and uses the hydraulic oil discharged from the pilot pump 15 to introduce a control pressure corresponding to the amount of lever operation into the pilot port of the control valve 172.

[0093] The discharge pressure sensor 28 includes a discharge pressure sensor 28L and a discharge pressure sensor 28R. The discharge pressure sensor 28L detects the discharge pressure of the left main pump 14L and outputs the detected value to the controller 30. The same applies to the discharge pressure sensor 28R.

[0094] The controller 30 receives the output of the operation sensor 29 and outputs a control command to the regulator 13 as necessary to change the discharge rate of the main pump 14. The controller 30 also receives the output of a control pressure sensor 19 provided upstream of the restrictor (negative control restrictor) 18 and outputs a control command to the regulator 13 as necessary to change the discharge rate of the main pump 14. The restrictor 18 includes a left restrictor 18L and a right restrictor 18R, and the control pressure sensor 19 includes a left control pressure sensor 19L and a right control pressure sensor 19R.

[0095] A left throttle 18L is disposed in the left center bypass line 40L between the hydraulic oil tank and the control valve 176L, which is located most downstream. Therefore, the flow of hydraulic oil discharged from the left main pump 14L is restricted by the left throttle 18L. The left throttle 18L generates a control pressure for controlling the left regulator 13L. The left control pressure sensor 19L detects this control pressure and outputs the detected value to the controller 30. The controller 30 controls the discharge rate of the left main pump 14L by adjusting the swash plate tilt angle of the left main pump 14L in accordance with this control pressure. The controller 30 decreases the discharge rate of the left main pump 14L as the control pressure increases, and increases the discharge rate of the left main pump 14L as the control pressure decreases. The discharge rate of the right main pump 14R is controlled in a similar manner.

[0096] Specifically, as shown in FIG. 3 , when the excavator 100 is in a standby state in which none of the hydraulic actuators are operated, the hydraulic oil discharged from the left main pump 14L passes through the left center bypass pipe 40L and reaches the left throttle 18L. The flow of hydraulic oil discharged from the left main pump 14L increases the control pressure generated upstream of the left throttle 18L. As a result, the controller 30 reduces the discharge rate of the left main pump 14L to the minimum allowable discharge rate, thereby suppressing pressure loss (pumping loss) that occurs when the discharged hydraulic oil passes through the left center bypass pipe 40L. On the other hand, when one of the hydraulic actuators is operated, the hydraulic oil discharged from the left main pump 14L flows into the hydraulic actuator to be operated via the control valve corresponding to the hydraulic actuator. The flow of hydraulic oil discharged from the left main pump 14L reduces or eliminates the amount of hydraulic oil reaching the left throttle 18L, thereby lowering the control pressure generated upstream of the left throttle 18L. As a result, the controller 30 increases the discharge rate of the left main pump 14L, circulating sufficient hydraulic oil to the hydraulic actuator to be operated and ensuring the drive of the hydraulic actuator to be operated. The controller 30 also controls the discharge rate of the right main pump 14R in a similar manner.

[0097] With the above-described configuration, the hydraulic system of Fig. 3 can suppress unnecessary energy consumption in the main pump 14 in a standby state. The unnecessary energy consumption includes pumping loss caused by the hydraulic oil discharged from the main pump 14 in the center bypass pipe 40. Furthermore, when operating a hydraulic actuator, the hydraulic system of Fig. 3 can reliably supply a necessary and sufficient amount of hydraulic oil from the main pump 14 to the hydraulic actuator to be operated.

[0098] That is, the controller 30 controls the regulator 13 so that the discharge amount is the smaller of a first discharge amount calculated so that the absorption power (absorption horsepower) of the main pump 14, which is expressed as the product of the discharge pressure and the discharge amount, does not exceed the output power (output horsepower) of the engine 11, and a second discharge amount calculated based on the control pressure detected by the control pressure sensor 19.

[0099] [Description of Functions of Machine Control Function Unit] When the machine control function unit 50 according to this embodiment receives operation of the arm 5 from the operator, it controls the movement of the boom 4 and the bucket 6 so that the toe of the bucket 6 follows the target construction surface in accordance with the movement of the arm 5.

[0100] 4 is a conceptual diagram showing an example of a target construction surface on which the shovel 100 according to this embodiment will perform construction. In the example shown in FIG. 4, the target construction surface on which the shovel 100 will perform construction includes a first target construction surface 1401 and a second target construction surface 1402. The first target construction surface 1401 and the second target construction surface 1402 intersect at a predetermined angle at a boundary 1403. In such a situation, it is difficult for the shovel 100 to move the bucket 6 so as to follow the first target construction surface 1401 and the second target construction surface 1402.

[0101] Fig. 5 is a diagram showing the movement trajectory of the bucket when a conventional machine control function is executed on the target construction surface shown in Fig. 4. In the example shown in Fig. 5, earth and sand 1501 has formed.

[0102] 5, when the bucket of a conventional excavator moves from a first position 6A to a first target construction surface 1401 and a second target construction surface 1402 in this order, the bucket moves along a trajectory 1502. For this reason, it is difficult to form a sharp edge at a boundary 1403 between the first target construction surface 1401 and the second target construction surface 1402.

[0103] Incidentally, when a shovel is used to perform construction on a slope, it is common to separately construct a first target construction surface 1401 and a second target construction surface 1402. For example, after the construction of the first target construction surface 1401 is completed, the construction of the second target construction surface 1402 is carried out.

[0104] In a conventional excavator, when starting construction on the second target construction surface 1402 using the machine control function, aligning the toe of the bucket with the boundary 1403 allows the toe of the bucket to move along the second target construction surface 1402. However, if the bucket is located even slightly further back than the boundary 1403 (towards the first target construction surface 1401), the machine control function controls the toe of the bucket to align with the first target construction surface 1401. Therefore, if the bucket is located even slightly further back than the boundary 1403 (towards the first target construction surface 1401), using the conventional machine control function would control the bucket to move to the second position 6B, for example.

[0105] When constructing the second target construction surface 1402 from the second position 6B, the bucket is controlled to move along the first target construction surface 1401 and then along the second target construction surface 1402, so there is a possibility that an edge cannot be properly formed at the boundary 1403 between the first target construction surface 1401 and the second target construction surface 1402. In this way, when using the machine control function in a situation where multiple target construction surfaces intersect, there is a problem in that it is difficult to align the bucket toe, etc. so that the operator can construct the desired target construction surface.

[0106] Therefore, the machine control function unit 50 according to this embodiment controls the bucket 6 to operate along an area extending from the target construction surface.

[0107] 6 is a diagram showing the guide surface set by the control of the machine control function unit 50 according to this embodiment and the movement of the bucket 6 along the guide surface. In the example shown in FIG. 6 , when the machine control function unit 50 receives an operation from the operator to select the second target construction surface 1402 as the construction target, the machine control function unit 50 sets an area extending from the second target construction surface 1402 in the reference coordinate system in which the excavator 100 exists as a virtual guide surface 1601. The guide surface 1601 is a surface extending from the second target construction surface 1402 in the vertical direction. Then, when the machine control function unit 50 receives an operation from the operator to start the machine control function, the machine control function unit 50 controls the operation of one or more of the bucket 6 and the boom 4 to move the toe of the bucket 6 to a position (e.g., third position 6C) where the toe of the bucket 6 contacts the guide surface 1601.

[0108] The reference coordinate system is, for example, the World Geodetic System. The World Geodetic System is a three-dimensional orthogonal XYZ coordinate system with its origin at the center of gravity of the Earth, its X axis pointing in the direction of the intersection of the Greenwich Meridian and the equator, its Y axis pointing in the direction of 90 degrees east longitude, and its Z axis pointing in the direction of the North Pole. The operator may, for example, determine an arbitrary point on the construction site as a reference point and set the target construction surface based on its relative positional relationship with the reference point via the information input device.

[0109] The guide surface 1601 is a surface extending from the second target construction surface 1402. Therefore, when the machine control function unit 50 receives an operation to close the arm 5 from the operator while the bucket 6 is in a position (for example, the third position 6C) in contact with the guide surface 1601, it performs control to move the toe of the bucket 6 along the trajectory 1602. This allows the toe of the bucket 6 to move from the boundary 1403 while maintaining contact with the second target construction surface 1402.

[0110] Therefore, the operator can easily move the bucket 6 to a position where construction on the second target construction surface 1402 is possible, without having to align the toe of the bucket 6 with the construction start position (e.g., boundary 1403) of the second target construction surface 1402. In addition, because the toe of the bucket 6 can be kept in contact with the edge of the second target construction surface 1402, an appropriate edge can be formed at the boundary 1403 between the first target construction surface 1401 and the second target construction surface 1402. This makes it possible to achieve improved construction accuracy.

[0111] [Components of the Machine Control Function Unit] Returning to Figure 2, the machine control function unit 50 will be described. The machine control function unit 50 executes a machine guidance function that operates the boom 4, arm 5, and bucket 6, for example, so that the toe of the bucket 6 moves along the target construction surface. Data related to the target construction surface is stored in advance in, for example, a storage medium 47.

[0112] The storage medium 47 is a non-volatile readable / writable storage medium. The storage medium 47 stores target construction surface information (an example of reference surface information) 47A that represents the shape of the target construction surface after construction by the shovel 100. The construction includes, for example, excavation work, rolling work, leveling work, etc.

[0113] The target construction surface information 47A is stored in the storage medium 47 based on, for example, a setting input by an operator through an information input device (not shown) or by being downloaded from an external device (for example, a predetermined management server). The target construction surface information 47A is expressed, for example, in the reference coordinate system described above.

[0114] The machine control function unit 50 acquires information from the boom angle sensor S1, arm angle sensor S2, bucket angle sensor S3, machine body inclination sensor S4, swing angle sensor S5, imaging device S6, boom rod pressure sensor S7R and boom bottom pressure sensor S7B, arm rod pressure sensor S8R and arm bottom pressure sensor S8B, bucket rod pressure sensor S9R and bucket bottom pressure sensor S9B, positioning device PS, operation sensor 29, communication device T1, input device 62, etc. Then, the machine control function unit 50 calculates the distance between the bucket 6 and the target construction surface based on the acquired information, for example, and automatically controls the operation of the attachment so that the back or toe of the bucket 6 coincides with the target construction surface.

[0115] The following describes the configuration of the machine control function unit 50 for controlling ground leveling work. The machine control function unit 50 includes a display control unit 501, a reception unit 502, a setting unit 503, an acquisition unit 504, and an automatic control unit 505 as detailed functional configurations for performing ground leveling work as a machine control function.

[0116] The display control unit 501 displays the image information on the display device 60. For example, the display control unit 501 displays, on the display device 60, image information representing the shape of the target construction surface indicated by the target construction surface information (an example of reference surface information) 47A from an arbitrary viewpoint in the reference coordinate system.

[0117] The reception unit 502 receives information input via the input device 62. For example, when a plurality of target construction surfaces are displayed on the display device 60, the reception unit 502 receives, via the input device 62, the selection of the target construction surface to be next constructed.

[0118] When the setting unit 503 receives the selection of a target construction surface, it sets a virtual guide surface in the reference coordinate system by extending the target construction surface. The guide surface is a virtual surface generated within the machine control function unit 50 as a reference for the machine control function unit 50 to guide the working portion of the bucket 6 (e.g., the toe or the back). The guide surface may have any shape that can guide the working portion of the bucket 6 (e.g., the toe or the back), and may be, for example, a flat surface or a curved surface. Note that this embodiment will describe an example in which a guide surface is set as an example of an area extended from the target construction surface, but the data to be set is not limited to a guide surface and may be, for example, a guide line, etc.

[0119] If the working portion is the tip of the bucket 6, the control object in the working portion of the bucket 6 (hereinafter simply referred to as the "control object of the bucket 6") may be set to a point on a curved or flat surface that constitutes the tip of a specific one of the multiple claws of the bucket 6. Furthermore, if the working portion is the back surface of the bucket 6, for example, the control object of the bucket 6 may include the curved or flat surface that constitutes the back surface of the bucket 6, a line segment defined on the flat or curved surface, a point defined on the flat or curved surface, etc.

[0120] The display control unit 501 may display the guide screen set by the setting unit 503. Next, the operation procedure up to setting the guide screen will be described.

[0121] FIG. 7 is a diagram showing the transition of screens displayed until the guide surface is set in the machine control function unit 50 according to this embodiment.

[0122] 7, the display control unit 501 displays the shape of the target construction surface indicated in the target construction surface information 47A on the display device 60. For the sake of explanation, the first screen 1701 shows the first target construction surface 1711 and the second target construction surface 1712 viewed from a side perspective, but the present invention is not limited to this screen example, and for example, the screen may display an appearance when the target construction surface is viewed from a perspective inside the cabin 10 of the excavator 100.

[0123] In this embodiment, the input device 62 is exemplified as a touch panel provided in the display area of ​​the display device 60. This allows the accepting unit 502 to accept the selection of an area displayed on the screen.

[0124] The reception unit 502 then receives a selection of the surface to be next constructed by the excavator 100 from the first target construction surface 1711 and the second target construction surface 1712. In the example shown in FIG. 7 , the reception unit 502 receives the selection of the second target construction surface 1712. In this embodiment, when there are multiple target construction surfaces, the reception unit 502 receives a selection of the target construction surface to be constructed from the multiple target construction surfaces. This allows the machine control function unit 50 to identify the target construction surface to be set as a guide surface when there are multiple target construction surfaces.

[0125] The second screen 1702 is an example screen displayed by the display control unit 501 after accepting the selection of the second target construction surface 1712. As shown in the second screen 1702, the display control unit 501 changes the display mode of the second target construction surface 1721 that has been selected. The second target construction surface 1721 may be, for example, changed so that the surface color is different from the others, or the outline may be made thicker.

[0126] Furthermore, a guide button 1722 is displayed on the second screen 1702. The guide button 1722 is a button for switching whether or not to set a guide surface.

[0127] Then, the receiving unit 502 receives a press of the guide button 1722. As a result, the setting unit 503 sets a guide surface that is an extension of the selected second target construction surface 1721. The target construction surface information 47A includes coordinate information of the second target construction surface 1721 in the reference coordinate system. Therefore, the setting unit 503 can calculate and set the coordinate information of the guide surface in the reference coordinate system by referring to the target construction surface information 47A.

[0128] Specifically, the setting unit 503 sets a guide surface that extends the second target construction surface 1721 in a direction in which the bucket 6 can move. The extension length may be any length, for example, 1 m. By setting the guide surface, when moving the bucket 6 along the second target construction surface 1721, the operator can be guided to move in the desired direction. This reduces the operational burden when moving the bucket 6. Furthermore, although the guide surface according to this embodiment is set to be approximately parallel to the target construction surface, it is not limited to being set approximately parallel, and may be tilted from the target construction surface as long as construction can be performed on the target construction surface from its end.

[0129] The third screen 1703 is an example of a screen displayed by the display control unit 501 after receiving a press of the guide button 1722. As shown in the third screen 1703, the display control unit 501 displays the pressed guide button 1731 in a different color than before the button was pressed.

[0130] Furthermore, the display control unit 501 displays, on the display device 60, image information showing, from a side perspective, the first target construction surface 1711, the second target construction surface 1721, and a guide surface 1732 extending from an end 1733 of the second target construction surface 1721. The display of the guide surface 1732 allows the operator to recognize how the bucket 6 will move when the machine control function is executed. This reduces the operational burden on the operator.

[0131] 2 , the acquisition unit 504 acquires detection information indicating the detection results of the various sensors in the excavator 100 from the various sensors. For example, the acquisition unit 504 acquires detection information from the boom angle sensor S1, the arm angle sensor S2, the bucket angle sensor S3, the machine body inclination sensor S4, the swing angle sensor S5, the imaging device S6, the boom rod pressure sensor S7R and the boom bottom pressure sensor S7B, the arm rod pressure sensor S8R and the arm bottom pressure sensor S8B, the bucket rod pressure sensor S9R and the bucket bottom pressure sensor S9B, and the positioning device PS.

[0132] Furthermore, the acquisition unit 504 acquires operation information indicating the content of the operation of the operation device 26 from the operation sensor 29, and acquires a signal corresponding to the operation input from the input device 62. The acquisition unit 504 also acquires information received from an external device via the communication device T1. For example, when the shovel 100 is remotely operated, the acquisition unit 504 may acquire an operation signal received from the external device via the communication device T1.

[0133] The automatic control unit 505 automatically assists the operator in manually operating the excavator 100 through the operation device 26 by automatically operating the actuators. Specifically, the automatic control unit 505 can individually and automatically adjust the pilot pressures acting on the control valves (specifically, the control valves 173, 175L, 175R, and 174) corresponding to the multiple hydraulic actuators (specifically, the swing hydraulic motor 2A, the boom cylinder 7, and the bucket cylinder 9). This allows the automatic control unit 505 to automatically operate each hydraulic actuator. Control of the machine control function by the automatic control unit 505 may be performed, for example, when a predetermined switch included in the input device 62 is pressed. The predetermined switch may be, for example, a machine control switch (hereinafter referred to as an "MC (Machine Control) switch"), and may be disposed as a push button switch at the tip of an operation lever of the operation device 26 (for example, the left operation lever 26L used to operate the arm 5) or may be separately provided near the operation lever of the operation device 26. The following description will be given on the assumption that the machine control function unit 50 performs control when a predetermined switch is pressed.

[0134] For example, when a specified switch or the like is pressed, the automatic control unit 505 controls the operation of the arm 5 in accordance with the operation to close or open the arm 5 received from the operation sensor 29, and also controls the boom angle and bucket angle (an example of the angle of the attachment) based on the detection information of the boom angle sensor S1 and the bucket angle sensor S3 so that the working part of the bucket 6 (for example, the tip or back) comes into contact with the target construction surface or guide surface.

[0135] As a specific control of the operation, when a predetermined switch or the like is pressed, the automatic control unit 505 automatically extends and retracts the boom cylinder 7 and bucket cylinder 9 in accordance with the operation of the arm cylinder 8 so that the boom angle and bucket angle are such that the target construction surface or guide surface and the position of the working portion of the bucket 6 approximately coincide. The operation of the arm cylinder 8 is controlled by the automatic control unit 505 so as to correspond to the operator's manual operation of opening or closing the arm 5.

[0136] As a result, when a specified switch or the like is pressed down and the working part of the bucket 6 (for example, the tip or back surface) is away from the target construction surface or guide surface, the automatic control unit 505 controls the boom cylinder 7 and the bucket cylinder 9 so that the working part of the bucket 6 (for example, the tip or back surface) comes into contact with the target construction surface or guide surface.

[0137] When the operator starts manually opening or closing the arm 5, the automatic control unit 505 controls the boom cylinder 7 and the bucket cylinder 9 so that the working part of the bucket 6 (for example, the tip or back) continues to contact the target construction surface or guide surface along with the opening or closing operation of the arm 5.

[0138] 6 , when the bucket 6 is located further back than the boundary 1403 (toward the first target construction surface 1401), the automatic control unit 505 operates the boom 4 and the bucket 6 so that the toe of the bucket 6 comes into contact with the guide surface 1601, and then performs control in accordance with the operation of the operator to move the toe of the bucket 6 along the guide surface 1601. This makes it possible to prevent the toe of the bucket 6 from coming into contact with the first target construction surface 1401. Therefore, the toe of the bucket 6 can move from the boundary 1403 along the second target construction surface 1402.

[0139] The timing at which the setting unit 503 cancels the setting of the guide surface may be any timing, and for example, the setting unit 503 may cancel the setting of the guide surface after the bucket 6 has finished moving along the guide surface due to operation control by the automatic control unit 505. Furthermore, the setting unit 503 may cancel the setting of the guide surface when the receiving unit 502 receives another press of the guide button.

[0140] In the above example, the setting unit 503 sets a guide surface for guiding the start position of construction by the bucket 6. However, this embodiment is not limited to setting a guide surface for guiding the start position of construction.

[0141] 8 is a diagram showing the guide surface set by the control of the machine control function unit 50 according to this embodiment and the movement of the bucket 6 along the guide surface. The example shown in Fig. 8 is an example in which construction is performed on a soil shape 1805, and shows a first target construction surface 1801 and a second target construction surface 1802 that show the shape after construction.

[0142] When the setting unit 503 receives an operation from the operator to select the first target construction surface 1801 as the construction target, it sets a virtual guide surface 1803 that is an extension of the first target construction surface 1801. The guide surface 1803 is a surface that is extended from an end 1804 of the first target construction surface 1801 in a direction in which the bucket 6 can move.

[0143] When the machine control function unit 50 receives an operation to close the arm 5 from the operator, it controls the operation of one or more of the bucket 6 and the boom 4, causing them to move along the trajectory 1806. In other words, the toe of the bucket 6 moves along the first target construction surface 1801, and then moves along the guide surface 1803. Therefore, construction can be performed so that the toe of the bucket 6 follows the first target construction surface 1801 all the way to the end 1804. This makes it possible to achieve improved construction accuracy.

[0144] In this embodiment, the case where two target construction surfaces intersect has been described. However, this embodiment is not limited to the case where two target construction surfaces intersect, and can also be applied to the case where three or more target construction surfaces are combined.

[0145] Fig. 9 is a diagram showing guide surfaces set by the control of the machine control function unit 50 according to this embodiment. The example shown in Fig. 9 is an example in which construction is performed on a soil shape 1904, and a first target construction surface 1901, a second target construction surface 1902, and a third target construction surface 1903 are shown as shapes after construction.

[0146] When the setting unit 503 receives an operation from the operator to select the second target construction surface 1902 as the construction target, it sets virtual guide surfaces 1905A and 1905B that are extensions of the second target construction surface 1902. The guide surface 1905A is a surface that extends from an end 1906 of the second target construction surface 1902 in a direction in which the bucket 6 can move. The guide surface 1905B is a surface that extends from an end 1907 of the second target construction surface 1902 in a direction in which the bucket 6 can move. As a result, the bucket 6 moves in the order of the guide surface 1905A, the second target construction surface 1902, and the guide surface 1905B, with the toe of the bucket 6 in contact with each surface. Therefore, the area between both ends of the second target construction surface 1902 can be properly constructed, thereby improving construction accuracy.

[0147] Next, a description will be given of the processing procedure executed by the machine control function unit 50 according to this embodiment. Fig. 10 is a flowchart showing the processing procedure executed by the machine control function unit 50 according to this embodiment.

[0148] First, the display control unit 501 displays one or more target construction surfaces included in the target construction surface information 47A when viewed from a predetermined viewpoint in the reference coordinate system (S2001).

[0149] Thereafter, the reception unit 502 determines whether or not the selection of the displayed target construction surface has been received (S2002). If it is determined that the selection has not been received (S2002: NO), the process ends.

[0150] On the other hand, if the reception unit 502 determines that it has received the selection of the displayed target construction surface (S2002: YES), the display control unit 501 changes the display mode of the selected target construction surface and displays a guide button (S2003).

[0151] Thereafter, the accepting unit 502 determines whether or not the pressing of the displayed guide button has been accepted (S2004). If it is determined that the pressing has not been accepted (S2004: NO), the process ends.

[0152] On the other hand, if the reception unit 502 determines that the displayed guide button has been pressed (S2004: YES), the setting unit 503 sets a guide surface that is an extension of the selected target construction surface (S2005).

[0153] Then, the display control unit 501 displays the set guidance screen (S2006).

[0154] The reception unit 502 determines whether or not pressing of the MC button has been received (S2007). If it is determined that pressing of the MC button has not been received (S2007: NO), the reception unit 502 waits until pressing of the MC button is received.

[0155] On the other hand, if the reception unit 502 determines that the MC button has been pressed (S2007: YES), the automatic control unit 505 starts operation control so that the tip of the bucket 6 comes into contact with the guide surface or the target construction surface (S2008).

[0156] Thereafter, the automatic control unit 505 performs operation control so that the tip of the bucket 6 moves along the guide surface or the target construction surface in response to the closing or opening operation of the arm 5 (S2009).

[0157] The machine control function unit 50 of this embodiment controls the operation of the bucket 6 and the boom 4 so that the tip of the bucket 6 follows a guide surface that is set to extend the target construction surface, thereby allowing the tip of the bucket 6 to work the target construction surface all the way to the edge, thereby achieving improved accuracy.

[0158] (Modification of the First Embodiment) In the above-described embodiment, a case where a guide surface is set by selecting a target construction surface on which a construction target is to be constructed has been described. However, the above-described embodiment shows only one example of setting a guide surface, and other aspects may also be used. Therefore, as a modification, an example of automatically setting a guide surface will be described.

[0159] FIG. 11 is an explanatory diagram showing a control procedure by the machine control function unit 50 according to a modified example of the first embodiment.

[0160] In FIG. 11, construction is performed on earth and sand 2103 along a first target construction surface 2101 , and then construction is performed along a second target construction surface 2102 .

[0161] In a first step 2151, the setting unit 503 sets a guide surface 2111 that is an extension of the first target construction surface 2101. The setting method of the guide surface 2111 may be, for example, to set the guide surface 2111 for the first target construction surface 2101 that is closest to the bucket 6 among multiple target construction surfaces based on the position of the bucket 6. Then, the automatic control unit 505 performs operation control so that the toe of the bucket 6 moves along the first target construction surface 2101 and the guide surface 2111.

[0162] In the second step 2152 , since the toe of the bucket 6 reaches the end of the guide surface 2111 , the setting unit 503 cancels the setting of the guide surface 2111 .

[0163] In the third step 2153, the setting unit 503 infers that the second target construction surface 2102 is the next construction target based on the position of the tip of the bucket 6 (which has reached the end of the guide surface 2111), and sets a guide surface 2131 that extends the second target construction surface 2102 that is inferred to be the next construction target.

[0164] In a fourth step 2154 , the automatic control unit 505 controls the operation of the bucket 6 and the boom 4 so that the toe of the bucket 6 comes into contact with the guide surface 2131 .

[0165] After the tip of the bucket 6 comes into contact with the guide surface 2131, the automatic control unit 505 controls the operation so that the tip of the bucket 6 moves along the guide surface and then along the second target construction surface 2102 in accordance with the closing or opening operation of the arm 5.

[0166] In this modification, the setting unit 503 sets and cancels the setting of the guide surface based on the position of the toe of the bucket 6. This reduces the operator's operations related to the guide surface, thereby improving operability.

[0167] Second Embodiment In the above-described embodiment, a case has been described in which an operator performs an operation inside the cabin 10. However, the above-described embodiment is not limited to a case in which an operator performs an operation inside the cabin 10. For example, a remote control system for an excavator 100 may perform the same processing as in the above-described embodiment. Therefore, in the second embodiment, a case in which a remote control system for an excavator sets a guide surface will be described.

[0168] An overview of the remote control system SYS according to the second embodiment will now be described with reference to Fig. 12. Fig. 12 is a schematic diagram showing an example of the remote control system SYS according to the second embodiment.

[0169] 12, the remote control system SYS according to the second embodiment includes a shovel 100 and a remote control room RC. The shovel 100 according to this embodiment has the same configuration as the above-described embodiments.

[0170] The excavator 100 and the remote control room RC are connected via a communication line NT so as to be able to send and receive data.

[0171] The shovel 100 is capable of wireless communication by using the communication device T1, and is able to send and receive data to and from devices (e.g., a remote control room RC) connected to the communication line NT.

[0172] The shovel 100 can then transmit information regarding the work site to the remote control room RC. This allows the remote control room RC to check the work site in accordance with the information from the shovel 100. Note that in this embodiment, the device that measures the work site is not limited to the shovel 100, and may be another type of device, such as a drone that flies over the work site, a fixed camera, or an imaging device that can be carried by the user.

[0173] For example, an imaging device S6 is provided in the shovel 100. The shovel 100 transmits a captured image showing the results of capturing an image of the work site by the imaging device S6 to the remote control room RC.

[0174] The remote operation system SYS may include one or more shovels 100. This allows the remote operation system SYS to provide information about the work site to the remote operation room RC through the multiple shovels 100.

[0175] <Configuration example of remote control room> The remote control room RC is equipped with a communication device T2, a remote controller R30, an operation device R26, an operation sensor R29, an input device R62, and display devices D1 and D2. The remote control room RC also has an operation seat DS where an operator OP who remotely operates the excavator 100 sits.

[0176] The communication device T2 is configured to control communication with the communication device T1 attached to the excavator 100.

[0177] The remote controller R30 (an example of a remote control unit) is a computing device that executes various calculations. In this embodiment, the remote controller R30 is configured as a microcomputer including a CPU and memory. The various functions of the remote controller R30 are realized by the CPU executing programs stored in the memory.

[0178] The display device D1 displays a screen based on information transmitted from the shovel 100 so that the operator OP in the remote control room RC can visually confirm the surroundings of the shovel 100. The display device D1 enables the operator to confirm the status of the work site, including the surroundings of the shovel 100, even though the operator is in the remote control room RC.

[0179] The display device D2 is provided in a location that is easily visible to the operator OP in the remote control room RC, and displays various information images under the control of the controller 30. For example, when the communication device T2 receives target construction surface information 47A from the excavator, it may display the shape of the target construction surface in the reference coordinate system.

[0180] The input device R62 is an example of a touch panel provided in the display area of ​​the display device D2. This allows selection of a target construction surface, as in the above-described embodiment. Information about the target construction surface selected by the input device R62 is then transmitted to the excavator 100 via the communication device T2.

[0181] The setting unit 503 of the machine control function unit 50 then sets the guide surface based on the received information. After that, the machine control function unit 50 transmits the information about the guide surface to the remote control room RC via the communication device T1.

[0182] The display device D2 displays the received guide surface, thereby enabling the operator OP in the remote control room RC to recognize that a guide surface has been set to guide the toe of the bucket 6. Then, the remote controller (an example of a remote control unit) R30 transmits an operation signal indicating the opening or closing operation of the arm 5 received by the operating device R26 to the excavator 100 via the communication device T2.

[0183] The machine control function unit 50 of the shovel 100 controls the operation of the bucket 6 and the boom 4 based on the received operation signal so as to move the tip of the bucket along the guide surface. This makes it possible to remotely control the shovel 100 from the remote control room RC. The subsequent control is the same as in the above-described embodiment.

[0184] <Function> In addition, in the above-described embodiment and modified example, by controlling the bucket 6 to move along a guide surface that extends the target construction surface selected by the operator from among the multiple target construction surfaces represented by the target construction surface information 47A, it is possible to prevent the bucket 6 from coming into contact with other target construction surfaces, thereby improving operability.

[0185] Furthermore, by moving the tip of the bucket 6 along the guide surface, construction can be performed from the edge of the selected target construction surface, thereby improving construction accuracy.

[0186] The above-described embodiment and modified examples have been described with reference to a case where the work machine is a shovel. However, the above-described embodiment and modified examples are not limited to a shovel, and may be applied to any work machine equipped with an attachment and a work tool.

[0187] While the embodiments of the work machine and work machine remote control system according to the present invention have been described above, the present invention is not limited to the above-described embodiments. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. Naturally, these also fall within the technical scope of the present invention.

[0188] This application claims priority based on Japanese Patent Application No. 2023-167694, filed on September 28, 2023, the entire contents of which are incorporated herein by reference.

[0189] REFERENCE SIGNS LIST 100 Excavator 1 Lower traveling body 2 Swing mechanism 3 Upper rotating body 4 Boom 5 Arm 6 Bucket 7 Boom cylinder 8 Arm cylinder 9 Bucket cylinder 17 Control valve unit S1 Boom angle sensor S2 Arm angle sensor S3 Bucket angle sensor S5 Swing angle sensor S6 Imaging device S7R, S7B, S8R, S8B, S9R, S9B Cylinder pressure sensor PS Positioning device T1 Communication device 26 Operation device 29 Operation sensor 30 Controller 31 Proportional valve 47 Storage medium 47A Target construction surface information 50 Machine control function unit 501 Display control unit 502 Reception unit 503 Setting unit 504 Acquisition unit 505 Automatic control unit 60 Display device 62 Input device SYS Remote operation system RC Remote operation room T2 Communication device R30 Remote controller R62 Input device D1, D2 Display device

Claims

1. A work machine comprising: a lower running body; an upper rotating body mounted on the lower running body so as to be freely rotatable; an attachment attached to the upper rotating body; a work tool provided at the tip of the attachment; a memory unit that stores reference plane information representing the shape of a surface after construction; and a control device configured to control the movement of the work tool along an area extending from the surface represented by the reference plane information.

2. The work machine according to claim 1, wherein the control device is configured, when it receives a selection of the surface represented by the reference surface information, to set an area extending from the selected surface as a virtual guide surface in a coordinate system in which the work machine exists, and to control the movement of the work tool along the guide surface.

3. A work machine according to claim 2, wherein the guide surface is configured to extend the surface represented by the reference surface information in a direction in which the work implement is movable.

4. A work machine as described in claim 2, wherein the control device is configured to display, on a display device, image information representing the surface represented by the reference surface information and the guide surface from a specified viewpoint in the coordinate system.

5. The work machine according to claim 2, wherein the control device is configured to cancel the setting of the guide surface after the work implement has moved along the guide surface.

6. A work machine as described in claim 1, wherein the control device is configured to set an area extending from a surface estimated to be the work target as a virtual guide surface based on the position of the work tool, and to control the movement of the work tool along the guide surface.

7. A remote control system for a work machine comprising: a remote control device having an operation device and a first communication device that transmits a signal received by the operation device; a work machine having a lower running body, an upper rotating body mounted so as to be freely rotatable on the lower running body, an attachment attached to the upper rotating body, a work tool provided at the tip of the attachment, a memory unit that stores reference plane information that represents the shape of the surface after construction is performed, a second communication device that receives the signal, and a control device configured to control the movement of the work tool along an area extending from the surface represented by the reference plane information based on the operation indicated by the signal.

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