Shovel and control device for a shovel

Abstract

A shovel (100) has a lower traveling body (1), an upper rotating body (3) rotatably mounted on the lower traveling body (1), and an attachment device mounted on the upper rotating body (3). The shovel (100) is configured to automatically decelerate or stop the rotation of the upper rotating body (3) when the upper rotating body (3) rotates, in anticipation of the attachment device crossing a design surface as a stop target. The shovel (100) can also be configured to prohibit a boom raising operation based on automatic control when the rotation of the upper rotating body (3) is decelerated or stopped.

Description

Technical Field

[0001] This invention relates to an excavator as an excavator and a control device for the excavator. Background Technology

[0002] Previously, a hydraulic excavator that was automatically controlled to perform leveling operations was known (for example, see Patent Document 1). The hydraulic excavation mechanism was configured to forcibly raise the boom when the tip of the bucket descended below the designed surface in order to avoid digging deeper than the designed surface.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: International Publication No. 2014 / 192474 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] However, if the boom is forcibly raised, it may cause the boom to come into contact with objects such as power lines located above the hydraulic excavator.

[0008] Therefore, it is preferable to provide an excavator that is more appropriately and automatically controlled.

[0009] Methods for solving problems

[0010] The excavator according to the embodiments of the present invention includes: a lower traveling body; an upper rotating body rotatably mounted on the lower traveling body; and an auxiliary device installed on the upper rotating body, wherein when the upper rotating body rotates, if interference between the auxiliary device and the surface of the controlled object is anticipated, the rotation of the upper rotating body is automatically decelerated or stopped.

[0011] Invention Effects

[0012] The above methods provide an excavator that is more appropriately and automatically controlled. Attached Figure Description

[0013] Figure 1 This is a side view of the excavator according to an embodiment of the present invention.

[0014] Figure 2 yes Figure 1 A top view of an excavator.

[0015] Figure 3 It means that it is carried on Figure 1 A diagram illustrating the structure of the hydraulic system of an excavator.

[0016] Figure 4AThis is a diagram of a part of the hydraulic system related to the operation of the boom cylinder.

[0017] Figure 4B This is a diagram of a part of the hydraulic system associated with the boom cylinder.

[0018] Figure 4C This is a diagram of a part of the hydraulic system associated with the bucket cylinder.

[0019] Figure 4D This is a diagram of a part of a hydraulic system associated with a rotary hydraulic motor.

[0020] Figure 5 This is a diagram illustrating an example of the controller's structure.

[0021] Figure 6 It is a 3D view of an excavator performing slope trimming operations.

[0022] Figure 7 This is a top view of an excavator performing slope trimming operations. Detailed Implementation

[0023] First, refer to Figure 1 and Figure 2 The excavator 100, which is an excavator according to an embodiment of the present invention, will be described. Figure 1 This is a side view of excavator 100. Figure 2 This is a top view of the excavator 100.

[0024] In this embodiment, the lower traveling body 1 of the excavator 100 includes tracks 1C. Tracks 1C are driven by a travel hydraulic motor 2M mounted on the lower traveling body 1, which serves as a travel actuator. Specifically, tracks 1C include a left track 1CL and a right track 1CR. The left track 1CL is driven by a left travel hydraulic motor 2ML, and the right track 1CR is driven by a right travel hydraulic motor 2MR.

[0025] An upper rotating body 3 is rotatably mounted on the lower traveling body 1 via a rotating mechanism 2. The rotating mechanism 2 is driven by a rotary hydraulic motor 2A mounted on the upper rotating body 3, which serves as a rotary actuator. However, the rotary actuator can also be a rotary electric generator, which serves as an electric actuator.

[0026] A boom 4 is mounted on the upper rotating body 3. A stick 5 is mounted at the front end of the boom 4, and a bucket 6, serving as an end-connection accessory, is mounted at the front end of the stick 5. The boom 4, stick 5, and bucket 6 constitute an example of an excavation accessory AT. The boom 4 is driven by a boom cylinder 7, the stick 5 by a stick cylinder 8, and the bucket 6 by a bucket cylinder 9. The boom cylinder 7, stick cylinder 8, and bucket cylinder 9 constitute the accessory actuator. The bucket 6 can be, for example, an inclined bucket. Furthermore, the bucket 6 can be equipped with a bucket tilting mechanism.

[0027] The boom 4 is supported vertically by the upper slewing body 3. A boom angle sensor S1 is mounted on the boom 4. The boom angle sensor S1 can detect the rotation angle of the boom 4, i.e., the boom angle θ1. The boom angle θ1 is, for example, the upward angle from the state where the boom 4 is at its maximum lowered position. Therefore, the boom angle θ1 is at its maximum when the boom 4 is at its maximum raised position.

[0028] The boom 5 is rotatably supported by the passive boom 4. Furthermore, a boom angle sensor S2 is mounted on the boom 5. The boom angle sensor S2 can detect the rotation angle of the boom 5, i.e., the boom angle θ2. The boom angle θ2 is, for example, the opening angle from the state of the boom 5 being retracted to its maximum extent. Therefore, the boom angle θ2 becomes maximum when the boom 5 is fully extended.

[0029] The bucket 6 is rotatably supported by the boom 5. Furthermore, a bucket angle sensor S3 is installed on the bucket 6. The bucket angle sensor S3 can detect the rotation angle of the bucket 6, i.e., the bucket angle θ3. The bucket angle θ3 is the opening angle from the state where the bucket 6 is retracted to its maximum extent. Therefore, the bucket angle θ3 is at its maximum when the bucket 6 is fully extended.

[0030] exist Figure 1 In this embodiment, the boom angle sensor S1, stick angle sensor S2, and bucket angle sensor S3 are each composed of a combination of an accelerometer and a gyroscope sensor. However, they may also be composed of only an accelerometer. Furthermore, the boom angle sensor S1 can be a stroke sensor installed on the boom cylinder 7, or it can be a rotary encoder, potentiometer, or inertial measurement device, etc. The same applies to the stick angle sensor S2 and the bucket angle sensor S3.

[0031] A driver's cab 10, serving as the cockpit, is mounted on the upper rotating body 3 and is equipped with a power source such as an engine 11. Furthermore, a spatial recognition device 70, an orientation detection device 71, a positioning device 73, a fuselage tilt sensor S4, and a rotational angular velocity sensor S5 are installed on the upper rotating body 3. Inside the driver's cab 10 are an operating device 26, a controller 30, an information input device 72, a display device D1, and a sound output device D2. Additionally, for convenience, in this specification, the side of the upper rotating body 3 where the digging auxiliary device AT is installed is designated as the front, and the side where the counterweight is installed is designated as the rear.

[0032] The spatial recognition device 70 is configured to identify objects existing in the three-dimensional space surrounding the excavator 100. Furthermore, the spatial recognition device 70 can also be configured to calculate the distance from the spatial recognition device 70 or the excavator 100 to the identified object. The spatial recognition device 70 may include, for example, an ultrasonic sensor, millimeter-wave radar, a camera device, a LiDAR, a distance image sensor, an infrared sensor, or any combination thereof. The camera device may be, for example, a monocular camera or a stereo camera. In this embodiment, the spatial recognition device 70 includes a front sensor 70F mounted on the front end of the upper surface of the cab 10, a rear sensor 70B mounted on the rear end of the upper surface of the upper rotating body 3, a left sensor 70L mounted on the left end of the upper surface of the upper rotating body 3, and a right sensor 70R mounted on the right end of the upper surface of the upper rotating body 3. An upper sensor for identifying objects existing in the space above the upper rotating body 3 may also be mounted on the excavator 100.

[0033] The orientation detection device 71 is configured to detect information related to the relative relationship between the orientation of the upper rotating body 3 and the orientation of the lower traveling body 1. The orientation detection device 71 may, for example, be a combination of a geomagnetic sensor mounted on the lower traveling body 1 and a geomagnetic sensor mounted on the upper rotating body 3. Alternatively, the orientation detection device 71 may be a combination of a GNSS receiver mounted on the lower traveling body 1 and a GNSS receiver mounted on the upper rotating body 3. The orientation detection device 71 may be a rotary encoder, a rotary position sensor, or any combination thereof. In a structure where the upper rotating body 3 is driven by a rotary electric generator, the orientation detection device 71 may also be a rotary transformer. The orientation detection device 71 may, for example, be mounted at a central joint associated with a rotary mechanism 2, which enables relative rotation between the lower traveling body 1 and the upper rotating body 3.

[0034] The orientation detection device 71 can also be composed of a camera mounted on the upper rotating body 3. In this case, the orientation detection device 71 performs known image processing on the image (input image) captured by the camera mounted on the upper rotating body 3 to detect the image of the lower traveling body 1 included in the input image. Furthermore, the orientation detection device 71 determines the length direction of the lower traveling body 1 by detecting the image of the lower traveling body 1 using known image recognition technology. It also derives the angle formed between the direction of the front-rear axis of the upper rotating body 3 and the length direction of the lower traveling body 1. The direction of the front-rear axis of the upper rotating body 3 is derived according to the mounting position of the camera. In particular, since the track 1C protrudes from the upper rotating body 3, the orientation detection device 71 can determine the length direction of the lower traveling body 1 by detecting the image of the track 1C. In this case, the orientation detection device 71 can be integrated into the controller 30. Furthermore, the camera can be a spatial recognition device 70.

[0035] The information input device 72 is configured to allow the excavator operator to input information to the controller 30. In this embodiment, the information input device 72 is a switch panel located near the display unit of the display device D1. However, the information input device 72 can be a touch panel located on the display unit of the display device D1, or it can be a voice input device such as a microphone located in the cab 10. Furthermore, the information input device 72 can be a communication device for acquiring information from the outside.

[0036] The positioning device 73 is configured to determine the position of the upper rotating body 3. In this embodiment, the positioning device 73 is a GNSS receiver that detects the position of the upper rotating body 3 and outputs the detected value to the controller 30. The positioning device 73 can also be a GNSS compass. In this case, the positioning device 73 can detect the position and orientation of the upper rotating body 3, and therefore also functions as an orientation detection device 71.

[0037] The body tilt sensor S4 detects the tilt angle of the upper rotating body 3 relative to a predetermined plane. In this embodiment, the body tilt sensor S4 is an acceleration sensor that detects the tilt angle of the upper rotating body 3 relative to the horizontal plane around the front and rear axes and the tilt angle around the left and right axes. The front and rear axes and the left and right axes of the upper rotating body 3 are, for example, orthogonal to each other and pass through a point on the rotation axis of the excavator 100, namely the center point of the excavator.

[0038] The rotational angular velocity sensor S5 detects the rotational angular velocity of the upper rotating body 3. In this embodiment, the rotational angular velocity sensor S5 is a gyroscope sensor. It can also be a rotary transformer, a rotary encoder, or any combination thereof. The rotational angular velocity sensor S5 can detect the rotational speed. The rotational speed can be calculated based on the rotational angular velocity.

[0039] Hereinafter, at least one of the boom angle sensor S1, stick angle sensor S2, bucket angle sensor S3, body tilt sensor S4, and slewing angular velocity sensor S5 will also be referred to as a posture detection device. The posture of the excavating auxiliary device AT is detected, for example, based on the outputs of the boom angle sensor S1, stick angle sensor S2, and bucket angle sensor S3 respectively.

[0040] Display device D1 is a device for displaying information. In this embodiment, display device D1 is a liquid crystal display installed in the driver's cab 10. However, display device D1 may also be a display of a mobile terminal such as a smartphone.

[0041] The sound output device D2 is a device for outputting sound. The sound output device D2 includes at least one of a device for outputting sound to the operator inside the cab 10 and a device for outputting sound to workers outside the cab 10. It can also be a speaker for a mobile terminal.

[0042] The operating device 26 is a means for 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.

[0043] The controller 30 is a control device for controlling the excavator 100. In this embodiment, the controller 30 is composed of a computer equipped with a CPU, volatile memory, and non-volatile memory. The controller 30 reads programs corresponding to various functions from the non-volatile memory and loads them into the volatile memory, and then causes the CPU to execute the corresponding processing. These functions include, for example, a device guidance function that guides the operator in manual operation of the excavator 100, and a device control function that supports manual operation of the excavator 100 or enables the excavator 100 to operate automatically or autonomously. The controller 30 may include a contact avoidance function that enables the excavator 100 to operate automatically or autonomously, or to stop the excavator 100, to avoid contact with objects within the monitoring range surrounding the excavator 100. Monitoring of objects around the excavator 100 is performed not only within the monitoring range but also outside the monitoring range.

[0044] Next, refer to Figure 3 An example of the structure of the hydraulic system mounted on the excavator 100 will be described. Figure 3 This is a diagram illustrating a structural example of the hydraulic system mounted on an excavator 100. Figure 3 The mechanical power transmission system, working oil pipeline, pilot line and electrical control system are represented by double lines, solid lines, dashed lines and dotted lines respectively.

[0045] 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, an output pressure sensor 28, an operating sensor 29, and a controller 30.

[0046] exist Figure 3 In this system, the hydraulic system is configured to circulate working oil from the main pump 14 driven by the engine 11 through the intermediate bypass line 40 or the parallel line 42 to the working oil tank.

[0047] Engine 11 is the drive source for excavator 100. In this embodiment, engine 11 is, for example, a diesel engine that operates at a specified speed. The output shaft of engine 11 is connected to the input shafts of main pump 14 and pilot pump 15, respectively.

[0048] The main pump 14 is configured to supply working oil to the control valve unit 17 via a working oil line. In this embodiment, the main pump 14 is a swashplate variable capacity hydraulic pump.

[0049] The regulator 13 is configured to control the discharge volume of the main pump 14. In this embodiment, the regulator 13 controls the discharge volume of the main pump 14 by adjusting the swashplate deflection angle of the main pump 14 according to the control command from the controller 30.

[0050] The pilot pump 15 is an example of a pilot pressure generating device, and is configured to supply working oil to hydraulic control equipment via pilot lines. In this embodiment, the pilot pump 15 is a fixed-capacity hydraulic pump. However, the pilot pressure generating device can be implemented by the main pump 14. That is, in addition to supplying working oil to the control valve unit 17 via working oil lines, the main pump 14 can also supply working oil to various hydraulic control devices via pilot lines. In this case, the pilot pump 15 can be omitted.

[0051] The control valve unit 17 is a hydraulic control device for controlling the hydraulic system in the excavator 100. In this embodiment, the control valve unit 17 includes control valves 171 to 176. Control valve 175 includes control valve 175L and control valve 175R, and control valve 176 includes control valve 176L and control valve 176R. The control valve unit 17 is configured to selectively supply working oil discharged from the main pump 14 to one or more hydraulic actuators via the control valves 171 to 176. For example, the control valves 171 to 176 control the flow rate of working oil from the main pump 14 to the hydraulic actuators and the flow rate of working oil from the hydraulic actuators to the working oil tank. The hydraulic actuators include a boom cylinder 7, a stick cylinder 8, a bucket cylinder 9, a left travel hydraulic motor 2ML, a right travel hydraulic motor 2MR, and a swing hydraulic motor 2A.

[0052] The operating device 26 is configured to allow an operator to operate the actuator. In this embodiment, the operating device 26 includes a hydraulic actuator operating device, which is configured to allow an operator to operate the hydraulic actuator. Specifically, the hydraulic actuator operating device is configured to supply working oil discharged from the pilot pump 15 via pilot lines to the pilot port of the corresponding control valve in the control valve unit 17. The pressure of the working oil supplied to each pilot port (pilot pressure) is a pressure corresponding to the operating direction and operating amount of the operating device 26 corresponding to each hydraulic actuator.

[0053] 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.

[0054] The operation sensor 29 is configured to detect the operation performed by the operator on 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 values ​​to the controller 30.

[0055] The main pump 14 includes a left main pump 14L and a right main pump 14R. The left main pump 14L circulates the working oil to the working oil tank via the left intermediate bypass line 40L or the left parallel line 42L, and the right main pump 14R circulates the working oil to the working oil tank via the right intermediate bypass line 40R or the right parallel line 42R.

[0056] The left middle bypass line 40L is a working oil line that passes through control valves 171, 173, 175L and 176L, which are configured in control valve unit 17. The right middle bypass line 40R is a working oil line that passes through control valves 172, 174, 175R and 176R, which are configured in control valve unit 17.

[0057] Control valve 171 is a slide valve that switches the flow of working oil by supplying working oil discharged from the left main pump 14L to the left travel hydraulic motor 2ML and discharging working oil discharged from the left travel hydraulic motor 2ML to the working oil tank.

[0058] Control valve 172 is a slide valve that switches the flow of working oil by supplying working oil discharged from the right main pump 14R to the right travel hydraulic motor 2MR and discharging working oil discharged from the right travel hydraulic motor 2MR to the working oil tank.

[0059] Control valve 173 is a spool valve that switches the flow of working oil by supplying working oil discharged from the left main pump 14L to the rotary hydraulic motor 2A and discharging working oil discharged from the rotary hydraulic motor 2A to the working oil tank.

[0060] Control valve 174 is a slide valve used to switch the flow of working oil by supplying working oil discharged from the right main pump 14R to the bucket cylinder 9 and discharging working oil from the bucket cylinder 9 to the working oil tank.

[0061] Control valve 175L is a slide valve that switches the flow of working oil by supplying working oil discharged from the left main pump 14L to the boom cylinder 7. Control valve 175R is a slide valve that switches the flow of working oil by supplying working oil discharged from the right main pump 14R to the boom cylinder 7 and discharging the working oil in the boom cylinder 7 to the working oil tank.

[0062] The control valve 176L is a slide valve used to switch the flow of working oil by supplying the working oil discharged from the left main pump 14L to the boom cylinder 8 and discharging the working oil in the boom cylinder 8 to the working oil tank.

[0063] Control valve 176R is a slide valve used to switch the flow of working oil by supplying working oil discharged from the right main pump 14R to the boom cylinder 8 and discharging the working oil in the boom cylinder 8 to the working oil tank.

[0064] The left parallel line 42L is a working oil line connected in parallel with the left intermediate bypass line 40L. When the flow of working oil through the left intermediate bypass line 40L is restricted or cut off by one of the control valves 171, 173, and 175L, the left parallel line 42L can supply working oil to a more downstream control valve. The right parallel line 42R is a working oil line connected in parallel with the right intermediate bypass line 40R. When the flow of working oil through the right intermediate bypass line 40R is restricted or cut off by one of the control valves 172, 174, and 175R, the right parallel line 42R can supply working oil to a more downstream control valve.

[0065] The regulator 13 includes a left regulator 13L and a right regulator 13R. The left regulator 13L controls the output of the left main pump 14L by adjusting the swashplate deflection angle of the left main pump 14L according to the output pressure of the left main pump 14L. Specifically, the left regulator 13L, for example, adjusts the swashplate deflection angle of the left main pump 14L to reduce the output, based on an increase in the output pressure of the left main pump 14L. The same applies to the right regulator 13R. This is to ensure that the absorbed power (absorbed horsepower) of the main pump 14, represented by the product of the output pressure and the output, does not exceed the output power (output horsepower) of the engine 11.

[0066] 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 travel lever 26DL and a right travel lever 26DR.

[0067] The left operating lever 26L is used for rotation and operation of the boom 5. When operating in the forward / backward direction, the left operating lever 26L uses the working oil discharged from the pilot pump 15 to introduce a control pressure corresponding to the lever operation amount into the pilot port of the control valve 176. Furthermore, when operating in the left / right direction, the working oil discharged from the pilot pump 15 uses the control pressure corresponding to the lever operation amount into the pilot port of the control valve 173.

[0068] Specifically, when the boom is retracted, the left operating lever 26L directs working oil to the right pilot port of control valve 176L and to the left pilot port of control valve 176R. Similarly, when the boom is extended, the left operating lever 26L directs working oil to the left pilot port of control valve 176L and to the right pilot port of control valve 176R. Furthermore, when the boom is turned to the left, the left operating lever 26L directs working oil to the left pilot port of control valve 173, and when the boom is turned to the right, the left operating lever 26L directs working oil to the right pilot port of control valve 173.

[0069] The right operating lever 26R is used to operate the boom 4 and the bucket 6. When operating in the forward / backward direction, the right operating lever 26R uses the working oil discharged from the pilot pump 15 to introduce a control pressure corresponding to the lever operation amount into the pilot port of the control valve 175. Furthermore, when operating in the left / right direction, the working oil discharged from the pilot pump 15 uses the control pressure corresponding to the lever operation amount into the pilot port of the control valve 174.

[0070] Specifically, when operating in the boom lowering direction, the right operating lever 26R introduces working fluid into the left pilot port of control valve 175R. Furthermore, when operating in the boom raising direction, the right operating lever 26R introduces working fluid into the right pilot port of control valve 175L and the left pilot port of control valve 175R. Moreover, when operating in the bucket retraction direction, the right operating lever 26R introduces working fluid into the right pilot port of control valve 174, and when operating in the bucket opening direction, the right operating lever 26R introduces working fluid into the left pilot port of control valve 174.

[0071] The travel lever 26D is used to operate the track 1C. Specifically, the left travel lever 26DL is used to operate the left track 1CL. It can also be configured to be linked with the left travel pedal. When operating in the forward or backward direction, the left travel lever 26DL uses the working oil discharged from the pilot pump 15 to introduce a control pressure corresponding to the lever operation amount into the pilot port of the control valve 171. The right travel lever 26DR is used to operate the right track 1CR. It can also be configured to be linked with the right travel pedal. When operating in the forward or backward direction, the right travel lever 26DR uses the working oil discharged from the pilot pump 15 to introduce a control pressure corresponding to the lever operation amount into the pilot port of the control valve 172.

[0072] The discharge pressure sensor 28 includes discharge pressure sensor 28L and discharge pressure sensor 28R. 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 discharge pressure sensor 28R.

[0073] The operation sensors 29 include operation sensors 29LA, 29LB, 29RA, 29RB, 29DL, and 29DR. Operation sensor 29LA detects the operator's actions on the left operating lever 26L in the forward / backward direction and outputs the detected value to the controller 30. The actions may include, for example, the lever's operating direction and the amount of lever operation (lever operating angle).

[0074] Similarly, operation sensor 29LB detects the operator's actions on the left control lever 26L in the left-right direction and outputs the detected value to controller 30. Operation sensor 29RA detects the operator's actions on the right control lever 26R in the forward-backward direction and outputs the detected value to controller 30. Operation sensor 29RB detects the operator's actions on the right control lever 26R in the left-right direction and outputs the detected value to controller 30. Operation sensor 29DL detects the operator's actions on the left travel lever 26DL in the forward-backward direction and outputs the detected value to controller 30. Operation sensor 29DR detects the operator's actions on the right travel lever 26DR in the forward-backward direction and outputs the detected value to controller 30.

[0075] The controller 30 receives the output of the operation sensor 29 and outputs control commands to the regulator 13 as needed to change the discharge volume of the main pump 14. Furthermore, the controller 30 receives the output of the control pressure sensor 19 located upstream of the throttle 18 and outputs control commands to the regulator 13 as needed to change the discharge volume of the main pump 14. The throttle 18 includes a left throttle 18L and a right throttle 18R, and the control pressure sensor 19 includes a left control pressure sensor 19L and a right control pressure sensor 19R.

[0076] In the left intermediate bypass line 40L, a left throttle 18L is positioned between the downstream control valve 176L and the working oil tank. Therefore, the flow of working oil discharged from the left main pump 14L is restricted by the left throttle 18L. Furthermore, the left throttle 18L generates a control pressure for controlling the left regulator 13L. A 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 swashplate deflection angle of the left main pump 14L according to this control pressure. The controller 30 is configured such that the higher the control pressure, the lower the discharge rate of the left main pump 14L; conversely, the lower the control pressure, the higher the discharge rate of the left main pump 14L. The discharge rate of the right main pump 14R is similarly controlled.

[0077] Specifically, such as Figure 3As shown, in the standby state where none of the hydraulic actuators in the excavator 100 are operated, the working oil discharged from the left main pump 14L reaches the left throttle 18L through the left intermediate bypass line 40L. Furthermore, the flow of the working oil discharged from the left main pump 14L increases the control pressure upstream of the left throttle 18L. As a result, the controller 30 reduces the discharge volume of the left main pump 14L to the minimum allowable discharge volume, thereby suppressing pressure loss (pumping loss) when the discharged working oil passes through the left intermediate bypass line 40L. On the other hand, when a particular hydraulic actuator is operated, the working oil discharged from the left main pump 14L flows into the hydraulic actuator corresponding to the operated actuator via the control valve. Furthermore, the flow of the working oil discharged from the left main pump 14L reduces or eliminates the amount reaching the left throttle 18L, thereby reducing the control pressure upstream of the left throttle 18L. As a result, controller 30 increases the output of the left main pump 14L to ensure sufficient working oil circulation to the hydraulic actuator of the workpiece, thereby ensuring the actuation of the hydraulic actuator. Similarly, controller 30 also controls the output of the right main pump 14R.

[0078] Based on the above structure, Figure 3 The hydraulic system can suppress unnecessary energy consumption in the main pump 14 in standby mode. Unnecessary energy consumption includes pumping losses caused by the working oil discharged from the main pump 14 in the intermediate bypass line 40. Furthermore, when the hydraulic actuator is activated, Figure 3 The hydraulic system is able to reliably supply the required amount of working oil from the main pump 14 to the hydraulic actuator of the work object.

[0079] Next, refer to Figures 4A to 4D The structure used by the controller 30 to operate the actuator through the device control function is described. Figures 4A to 4D This is a diagram showing a portion of the hydraulic system extracted. Specifically, Figure 4A This diagram shows the hydraulic system components related to the operation of the boom cylinder 8. Figure 4B This is a diagram showing the hydraulic system components related to the operation of boom cylinder 7. Figure 4C This diagram shows the hydraulic system components related to the operation of the bucket cylinder 9. Figure 4D This is a diagram showing the hydraulic system components related to the operation of the rotary hydraulic motor 2A.

[0080] like Figures 4A to 4D As shown, the hydraulic system includes a proportional valve 31. The proportional valve 31 includes proportional valves 31AL to 31DL and 31AR to 31DR.

[0081] The proportional valve 31 functions as a control valve for equipment control. The proportional valve 31 is disposed in the pipeline connecting the pilot pump 15 and the pilot port of the corresponding control valve within the control valve unit 17, and is configured to change the flow area of ​​this pipeline. In this embodiment, the proportional valve 31 operates according to a control command output by the controller 30. Therefore, the controller 30 can supply the working oil discharged from the pilot pump 15 to the pilot port of the corresponding control valve within the control valve unit 17 via the proportional valve 31, independent of the operator's operation of the operating device 26. Furthermore, the controller 30 can cause the pilot pressure generated by the proportional valve 31 to act on the pilot port of the corresponding control valve.

[0082] With this structure, the controller 30 can operate the hydraulic actuator corresponding to the specific operating device 26 even when no operation is performed on the specific operating device 26. Furthermore, even when the specific operating device 26 is operated, the controller 30 can forcibly stop the operation of the hydraulic actuator corresponding to the specific operating device 26.

[0083] For example, such as Figure 4A As shown, the left operating lever 26L is used to operate the boom 5. Specifically, the left operating lever 26L uses the working oil discharged by the pilot pump 15 to apply a pilot pressure corresponding to the operation in the forward / backward direction to the pilot port of the control valve 176. More specifically, when the operation is performed in the boom retraction direction (rearward direction), the left operating lever 26L applies a pilot pressure corresponding to the operation amount to the right pilot port of the control valve 176L and the left pilot port of the control valve 176R. Furthermore, when the operation is performed in the boom opening direction (forward direction), the left operating lever 26L applies a pilot pressure corresponding to the operation amount to the left pilot port of the control valve 176L and the right pilot port of the control valve 176R.

[0084] A switch NS is provided on the left operating lever 26L. In this embodiment, the switch NS is a push-button switch located at the front end of the left operating lever 26L. The operator can operate the left operating lever 26L while pressing the switch NS. The switch NS can also be located on the right operating lever 26R, or in other locations within the cab 10.

[0085] The operation sensor 29LA detects the operation performed by the operator on the left operating lever 26L in the forward and backward direction, and outputs the detected value to the controller 30.

[0086] Proportional valve 31AL operates according to a control command (current command) output by controller 30. It adjusts the pilot pressure generated by the working oil introduced from pilot pump 15 via proportional valve 31AL to the right pilot port of control valve 176L and the left pilot port of control valve 176R. Proportional valve 31AR operates according to a control command (current command) output by controller 30. It also adjusts the pilot pressure generated by the working oil introduced from pilot pump 15 via proportional valve 31AR to the left pilot port of control valve 176L and the right pilot port of control valve 176R. Proportional valve 31AL can adjust the pilot pressure in a way that allows control valves 176L and 176R to be stopped at any valve position. Similarly, proportional valve 31AR can adjust the pilot pressure in a way that allows control valves 176L and 176R to be stopped at any valve position.

[0087] With this structure, the controller 30 can supply working oil discharged by the pilot pump 15 to the right pilot port of the control valve 176L and the left pilot port of the control valve 176R via the proportional valve 31AL, based on the stick retraction operation performed by the operator. Furthermore, the controller 30 can supply working oil discharged by the pilot pump 15 to the right pilot port of the control valve 176L and the left pilot port of the control valve 176R via the proportional valve 31AL, regardless of the stick retraction operation performed by the operator. That is, the controller 30 can retract the stick 5 either based on the stick retraction operation performed by the operator or without the stick retraction operation performed by the operator.

[0088] Furthermore, the controller 30 can supply working oil discharged from the pilot pump 15 via the proportional valve 31AR to the left pilot port of the control valve 176L and the right pilot port of the control valve 176R according to the boom opening operation performed by the operator. Also, the controller 30 can supply working oil discharged from the pilot pump 15 via the proportional valve 31AR to the left pilot port of the control valve 176L and the right pilot port of the control valve 176R independently of the boom opening operation performed by the operator. That is, the controller 30 can open the boom 5 either according to the boom opening operation performed by the operator or independently of the boom opening operation performed by the operator.

[0089] Furthermore, through this structure, even when the operator performs the boom retraction operation, the controller 30 can reduce the pilot pressure acting on the closed-side pilot port of the control valve 176 (the left pilot port of control valve 176L and the right pilot port of control valve 176R) as needed, forcibly stopping the boom 5 retraction action. The same applies to the case where the boom 5 is forcibly stopped when the operator performs the boom opening operation.

[0090] Alternatively, even when the operator retracts the stick, the controller 30 can, as needed, control the proportional valve 31AR to increase the pilot pressure acting on the open pilot port of the control valve 176 (the right pilot port of control valve 176L and the left pilot port of control valve 176R), located on the side opposite to the closed pilot port of control valve 176, forcibly returning control valve 176 to the neutral position, thereby forcibly stopping the retraction of the stick 5. The same applies to the case where the stick opening operation is forcibly stopped when the operator opens the stick.

[0091] Furthermore, the following references are omitted. Figures 4B to 4D The explanation provided is the same, but the situations regarding forcibly stopping the movement of boom 4 when the operator performs boom raising or lowering operations, forcibly stopping the movement of bucket 6 when the operator performs bucket retraction or opening operations, and forcibly stopping the rotation of the upper slewing body 3 when the operator performs slewing operations are also the same. Furthermore, the situations regarding forcibly stopping the movement of the lower traveling body 1 when the operator performs traveling operations are also the same.

[0092] And, as Figure 4B As shown, the right operating lever 26R is used to operate the boom 4. Specifically, the right operating lever 26R uses the working oil discharged by the pilot pump 15 to apply a pilot pressure corresponding to the operation in the forward / backward direction to the pilot port of the control valve 175. More specifically, when the operation is performed in the boom lifting direction (rearward direction), the right operating lever 26R applies a pilot pressure corresponding to the operation amount to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R. Furthermore, when the operation is performed in the boom lowering direction (forward direction), the right operating lever 26R applies a pilot pressure corresponding to the operation amount to the right pilot port of the control valve 175R.

[0093] The operation sensor 29RA detects the operation performed by the operator on the right operating lever 26R in the forward and backward direction, and outputs the detected value to the controller 30.

[0094] Proportional valve 31BL operates according to the control command (current command) output by controller 30. It adjusts the pilot pressure generated by the working oil introduced from pilot pump 15 via proportional valve 31BL to the right pilot port of control valve 175L and the left pilot port of control valve 175R. Proportional valve 31BR operates according to the control command (current command) output by controller 30. It adjusts the pilot pressure generated by the working oil introduced from pilot pump 15 via proportional valve 31BR to the right pilot port of control valve 175R. Proportional valve 31BL can adjust the pilot pressure in a way that allows control valves 175L and 175R to be stopped at any valve position. Proportional valve 31BR can adjust the pilot pressure in a way that allows control valve 175R to be stopped at any valve position.

[0095] With this structure, the controller 30 can supply working oil discharged from the pilot pump 15 via the proportional valve 31BL to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R according to the boom lifting operation performed by the operator. Furthermore, the controller 30 can supply working oil discharged from the pilot pump 15 via the proportional valve 31BL to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R independently of the boom lifting operation performed by the operator. That is, the controller 30 can lift the boom 4 either according to the boom lifting operation performed by the operator or independently of the boom lifting operation performed by the operator.

[0096] Furthermore, the controller 30 can supply working oil discharged from the pilot pump 15 to the right pilot port of the control valve 175R via the proportional valve 31BR according to the boom lowering operation performed by the operator. Also, the controller 30 can supply working oil discharged from the pilot pump 15 to the right pilot port of the control valve 175R via the proportional valve 31BR regardless of the boom lowering operation performed by the operator. That is, the controller 30 can lower the boom 4 either according to the boom lowering operation performed by the operator or regardless of the boom lowering operation performed by the operator.

[0097] And, as Figure 4C As shown, the right operating lever 26R is used to operate the bucket 6. Specifically, the right operating lever 26R uses the working oil discharged by the pilot pump 15 to apply pilot pressure corresponding to the operation in the left and right directions to the pilot port of the control valve 174. More specifically, when the operation is performed in the bucket retraction direction (left direction), the right operating lever 26R applies pilot pressure corresponding to the operation amount to the left pilot port of the control valve 174. And, when the operation is performed in the bucket opening direction (right direction), the right operating lever 26R applies pilot pressure corresponding to the operation amount to the right pilot port of the control valve 174.

[0098] The operation sensor 29RB detects the operation performed by the operator on the right operating lever 26R in the left and right directions, and outputs the detected value to the controller 30.

[0099] Proportional valve 31CL operates according to the control command (current command) output by controller 30. It adjusts the pilot pressure generated by the working oil introduced from pilot pump 15 via proportional valve 31CL to the left pilot port of control valve 174. Proportional valve 31CR operates according to the control command (current command) output by controller 30. It adjusts the pilot pressure generated by the working oil introduced from pilot pump 15 via proportional valve 31CR to the right pilot port of control valve 174. Proportional valve 31CL can adjust the pilot pressure in a way that allows control valve 174 to stop at any valve position. Similarly, proportional valve 31CR can adjust the pilot pressure in a way that allows control valve 174 to stop at any valve position.

[0100] With this structure, the controller 30 can supply working oil discharged by the pilot pump 15 to the left pilot port of the control valve 174 via the proportional valve 31CL according to the bucket retraction operation performed by the operator. Furthermore, the controller 30 can supply working oil discharged by the pilot pump 15 to the left pilot port of the control valve 174 via the proportional valve 31CL regardless of the bucket retraction operation performed by the operator. That is, the controller 30 can retract the bucket 6 either according to the bucket retraction operation performed by the operator or without the bucket retraction operation performed by the operator.

[0101] Furthermore, the controller 30 can supply working oil discharged from the pilot pump 15 to the right pilot port of the control valve 174 via the proportional valve 31CR according to the bucket opening operation performed by the operator. Also, the controller 30 can supply working oil discharged from the pilot pump 15 to the right pilot port of the control valve 174 via the proportional valve 31CR regardless of the bucket opening operation performed by the operator. That is, the controller 30 can open the bucket 6 either according to the bucket opening operation performed by the operator or regardless of the bucket opening operation performed by the operator.

[0102] And, as Figure 4D As shown, the left operating lever 26L is also used to operate the rotary mechanism 2. Specifically, the left operating lever 26L uses the working oil discharged by the pilot pump 15 to apply a pilot pressure corresponding to the operation in the left and right directions to the pilot port of the control valve 173. More specifically, when the operation is performed in the left rotary direction (left direction), the left operating lever 26L applies a pilot pressure corresponding to the operation amount to the left pilot port of the control valve 173. And, when the operation is performed in the right rotary direction (right direction), the left operating lever 26L applies a pilot pressure corresponding to the operation amount to the right pilot port of the control valve 173.

[0103] The operation sensor 29LB detects the operation performed by the operator on the left and right control lever 26L and outputs the detected value to the controller 30.

[0104] Proportional valve 31DL operates according to the control command (current command) output by controller 30. It adjusts the pilot pressure generated by the working oil introduced from pilot pump 15 via proportional valve 31DL to the left pilot port of control valve 173. Proportional valve 31DR operates according to the control command (current command) output by controller 30. It adjusts the pilot pressure generated by the working oil introduced from pilot pump 15 via proportional valve 31DR to the right pilot port of control valve 173. Proportional valve 31DL can adjust the pilot pressure in a way that allows control valve 173 to stop at any valve position. Similarly, proportional valve 31DR can adjust the pilot pressure in a way that allows control valve 173 to stop at any valve position.

[0105] With this structure, the controller 30 can supply working oil discharged by the pilot pump 15 to the left pilot port of the control valve 173 via the proportional valve 31DL according to the left turn operation performed by the operator. Furthermore, the controller 30 can supply working oil discharged by the pilot pump 15 to the left pilot port of the control valve 173 via the proportional valve 31DL regardless of the left turn operation performed by the operator. That is, the controller 30 can cause the slewing mechanism 2 to rotate leftward either according to the left turn operation performed by the operator or without the left turn operation performed by the operator.

[0106] Furthermore, the controller 30 can supply working oil discharged from the pilot pump 15 to the right pilot port of the control valve 173 via the proportional valve 31DR based on the right turn operation performed by the operator. Also, the controller 30 can supply working oil discharged from the pilot pump 15 to the right pilot port of the control valve 173 via the proportional valve 31DR regardless of the right turn operation performed by the operator. In other words, the controller 30 can cause the slewing mechanism 2 to rotate to the right either based on or without the right turn operation performed by the operator.

[0107] The excavator 100 may have a structure that enables the lower traveling body 1 to move forward and backward automatically. In this case, the hydraulic system parts related to the operation of the left travel hydraulic motor 2ML and the hydraulic system parts related to the operation of the right travel hydraulic motor 2MR may be configured to be the same as the hydraulic system parts related to the operation of the boom cylinder 7.

[0108] Furthermore, the excavator 100 may have a structure that enables the bucket tilting mechanism to operate automatically. In this case, the hydraulic system components related to the bucket tilting cylinder constituting the bucket tilting mechanism may be configured to be the same as the hydraulic system components related to the operation of the boom cylinder 7.

[0109] Furthermore, while an electric operating lever (operating device 26) has been described, a hydraulic operating lever can also be used instead of an electric one. In this case, the lever operation amount of the hydraulic operating lever can be detected in pressure form by a pressure sensor and input to the controller 30. Additionally, a solenoid valve can be configured between the operating device 26 (hydraulic operating lever) and the pilot port of each control valve. The solenoid valve is configured to operate based on an electrical signal from the controller 30. With this configuration, if manual operation is performed using the operating device 26 (hydraulic operating lever), the operating device 26 increases or decreases the pilot pressure according to the lever operation amount, thereby moving each control valve. Furthermore, each control valve can be configured as a solenoid spool valve. In this case, the solenoid spool valve operates based on an electrical signal from the controller 30 corresponding to the lever operation amount of the electric operating lever.

[0110] Next, refer to Figure 5 The structure of controller 30 is described in an example. Figure 5 This is a diagram illustrating a structural example of the controller 30. Figure 5 In this controller 30, the controller is configured to receive signals from at least one of the following: a posture detection device, an operating device 26, a spatial recognition device 70, an orientation detection device 71, an information input device 72, a positioning device 73, and a switch NS, to perform various calculations, and to output control commands to at least one of the following: a proportional valve 31, a display device D1, and a sound output device D2. The posture detection device includes a boom angle sensor S1, a stick angle sensor S2, a bucket angle sensor S3, a body tilt sensor S4, and a slewing angular velocity sensor S5. The controller 30 has a position calculation unit 30A, a track acquisition unit 30B, and an automatic control unit 30C as functional components. Each functional component can be implemented in hardware or software. For ease of explanation, the position calculation unit 30A, the track acquisition unit 30B, and the automatic control unit 30C are shown separately, but they do not need to be physically distinguished and can be composed of software or hardware components that are generally applicable in whole or in part.

[0111] The position calculation unit 30A is configured to calculate the position of the object being measured. In this embodiment, the position calculation unit 30A calculates the coordinates of a specified part of the auxiliary device in a reference coordinate system. The specified part is, for example, the tip of the bucket 6. Specifically, the tip of the bucket 6 is the tip of the central claw among the plurality of claws installed at the front end of the bucket 6. However, the tip of the bucket 6 may also be the tip of the left claw among the plurality of claws installed at the front end of the bucket 6, or it may be the tip of the right claw among the plurality of claws installed at the front end of the bucket 6. The origin of the reference coordinate system is, for example, the intersection of the rotation axis and the ground contact surface of the excavator 100. The reference coordinate system is, for example, an XYZ rectangular coordinate system, and has an X-axis parallel to the front-rear axis of the excavator 100, a Y-axis parallel to the left-right axis of the excavator 100, and a Z-axis parallel to the rotation axis of the excavator 100. The position calculation unit 30A calculates the coordinates of the tip of the bucket 6 based on the rotation angles of the boom 4, stick 5, and bucket 6, for example. The position calculation unit 30A can calculate not only the coordinates of the front end of the central claw, but also the coordinates of the front ends of the left and right claws. In this case, the position calculation unit 30A can utilize the output of the body tilt sensor S4.

[0112] The track acquisition unit 30B is configured to acquire the target track, which is the track followed by a predetermined part of the auxiliary device when the excavator 100 is operated autonomously. In this embodiment, the track acquisition unit 30B acquires the target track used by the automatic control unit 30C when the excavator 100 is operated autonomously. Specifically, the track acquisition unit 30B derives the target track based on data related to the design surface stored in a non-volatile storage device. The track acquisition unit 30B may also derive the target track based on information related to the terrain around the excavator 100 identified by the spatial recognition device 70. Alternatively, the track acquisition unit 30B may derive information related to the past trajectory of the tip of the bucket 6 based on past outputs of the posture detection device stored in a volatile storage device, and derive the target track based on this information. Alternatively, the track acquisition unit 30B may derive the target track based on the current position of a predetermined part of the auxiliary device and data related to the design surface.

[0113] The automatic control unit 30C is configured to enable the excavator 100 to operate autonomously. In this embodiment, the automatic control unit 30C is configured to move a predetermined part of the auxiliary device along a target track acquired by the track acquisition unit 30B when predetermined start conditions are met. Specifically, when the operating device 26 is operated while the switch NS is pressed, the excavator 100 is operated autonomously to move the predetermined part along the target track.

[0114] In this embodiment, the automatic control unit 30C is configured to support manual operation of the excavator by the operator through autonomous operation of the actuators. For example, when the operator manually retracts the boom while pressing the switch NS, the automatic control unit 30C can autonomously extend or retract at least one of the boom cylinder 7, boom cylinder 8, and bucket cylinder 9 to align the target track with the tip of the bucket 6. At this time, the operator can retract the boom 5 simultaneously by operating the left control lever 26L in the boom retraction direction, for example, to align the tip of the bucket 6 with the target track.

[0115] In this embodiment, the automatic control unit 30C applies a control command (current command) to the proportional valve 31 to individually adjust the pilot pressure acting on the control valve corresponding to each actuator, thereby enabling each actuator to operate autonomously. For example, regardless of whether the right operating lever 26R is tilted, at least one of the boom cylinder 7 and bucket cylinder 9 can be actuated.

[0116] Next, refer to Figure 6 and Figure 7 The process by which the controller 30 stops the slewing motion through automatic control is explained. Figure 6 This is a 3D view of the excavator 100 when its slewing motion is stopped by automatic control. Figure 7 This is a top view of an excavator 100 whose slewing motion is stopped by automatic control.

[0117] In addition, Figure 6 and Figure 7 In the diagram, the range NR represents the area of ​​the unfinished slope (upward slope), that is, the area where the ground surface is inconsistent with the design surface, while the range CS represents the area of ​​the completed slope (upward slope), that is, the area where the ground surface is consistent with the design surface.

[0118] Figure 6 and Figure 7 This refers to an excavator 100 performing slope trimming operations. The slope trimming operations include excavation work (scraping sand from the slope using the bucket 6) and discharge work (discharging the sand collected in the bucket 6 during the excavation to another location). Specifically, in Figure 7 The excavator 100A, depicted with a dashed line, represents the state of excavator 100 after completing the soil removal operation. Furthermore, in... Figure 7 The image of excavator 100C, depicted with a single-dot dashed line, represents the state of excavator 100 when it is facing the slope (incline) in order to perform the next excavation operation.

[0119] Additionally, "to make the excavator 100 face the slope" means, for example, that the excavator 100 rotates around the pivot axis 2X so that the back of the bucket 6 is parallel to the slope (design surface). Furthermore, in Figure 7In the example shown, since excavator 100 stops its rotation in the state represented by excavator 100B (described by solid lines), it will not actually reach the state represented by excavator 100C. Therefore, excavator 100C represents the hypothetical state of excavator 100.

[0120] Furthermore, in Figure 7 Arrow AR indicates the rotation of the upper rotating body 3 from the state of excavator 100 (represented by excavator 100A) when the excavator 100 has completed the soil removal operation, to the state of excavator 100 (represented by excavator 100C) when the excavator 100 is facing the slope (incline). This rotation is achieved by tilting the left operating lever 26L to the left (leftward direction) while the operator presses the switch NS. Furthermore, the rotation radius at this time is equivalent to the working radius R1.

[0121] Furthermore, in Figure 7 The excavator 100B, depicted in solid lines, represents the state of the excavator 100 when its slewing motion is stopped by automatic control. Figure 6 The excavator 100 shown is equivalent to the excavator 100B.

[0122] Furthermore, in Figure 7 In the diagram, dashed line L0 represents the centerline of excavator 100 (excavator 100A) when the soil removal operation is completed; dashed line L2 represents the centerline of excavator 100 (excavator 100B) when the slewing motion is stopped by automatic control according to the present invention; and dashed line L4 represents the centerline of excavator 100 (excavator 100C) when facing the inclined plane (slope) as the design surface. Furthermore, in Figure 7 In the diagram, dashed line L1 represents the centerline of the excavator 100 when deceleration of the slewing motion begins via automatic control, and dashed line L3 represents the centerline of the excavator 100 when the specified part of the excavating attachment AT contacts the inclined plane if the slewing motion continues without automatic control. Additionally, arrow AR indicates deceleration of the slewing motion by using a dotted line to represent the portion near the end. The dashed line L3 (the position where the specified part of the excavating attachment AT contacts the inclined plane) is calculated based on the height of the bucket 6 (or the posture of the excavating attachment AT) and the slewing radius of the excavator 100 corresponding to dashed line L1. Therefore, if the height of the bucket 6 (or the posture of the excavating attachment AT) and the slewing radius change during slewing, the position of contact with the designed surface (the angle of dashed line L3) also changes. Furthermore, dashed line L3 can also be calculated based on the height of the bucket 6 (or the posture of the excavating attachment AT) and the slewing radius during excavation.

[0123] For example, when the left operating lever 26L is operated and the slewing action is initiated while the switch NS is pressed, the controller 30 calculates the trajectory (hereinafter referred to as the "slewing trajectory") followed by a specified part of the auxiliary device (in this example, a specified point in the bucket 6). This slewing trajectory is calculated, for example, based on information related to the position of the upper rotating body 3 output by the positioning device 73 and information related to the posture of the digging auxiliary device AT output by the posture detection device. Figure 7 The rotary track is represented by the dashed line LC.

[0124] Furthermore, while continuing the slewing motion, before the excavator 100 faces the slope, the controller 30 determines whether the bucket 6 is in contact with the design surface, that is, whether the bucket 6 has exceeded the design surface and dug into the slope. Specifically, the controller 30 determines whether the slewing track followed by a specified point in the bucket 6 intersects the design surface.

[0125] This determination is based, for example, on data related to the design surface stored in a non-volatile storage device, information related to the position of the upper rotating body 3 output by the positioning device 73, and information related to the posture of the excavation auxiliary device AT output by the posture detection device. Additionally, the controller 30 can also determine whether the bucket 6 is in contact with the design surface based on information output by the space recognition device 70.

[0126] If it is determined that the bucket 6 is in contact with the design surface, the controller 30 stops its rotation operation when a predetermined condition is met. The predetermined condition is, for example, whether the distance (hereinafter referred to as the "calculated distance") between the current position of a predetermined point in the bucket 6 and the contact point (reference point P3) is less than a predetermined distance. Furthermore, the contact point corresponds to the estimated position of the predetermined point in the bucket 6 when it contacts the design surface before the excavator 100 faces the slope (incline) during continued rotation. Figure 7 In the example shown, the calculated distance is the distance along the rotary track represented by the dashed line LC. However, the calculated distance can also be the straight-line distance between the current position of a specified point in bucket 6 and the contact point.

[0127] Furthermore, even when the slewing motion is slowed down or stopped, if a slewing operation is subsequently performed in the opposite direction to the slewing direction before the specified condition was met, the controller 30 allows the slewing motion corresponding to that operation. For example, even if the left slewing motion is slowed down or stopped due to the determination that the specified condition was met, if a right slewing operation is subsequently performed, the controller 30 will cause the upper slewing body 3 to rotate to the right according to that right slewing operation. That is, the controller 30 does not restrict or prohibit slewing operations used to move the bucket 6 away from the slope (incline). Furthermore, the controller 30 does not restrict or prohibit operations other than slewing operations, such as boom lifting operations.

[0128] Furthermore, the controller 30 is configured such that even when specified conditions are met, the automatic control-based slewing operation will not be stopped without pressing the switch NS. This is because it is possible for the operator to intentionally bring the bucket 6 into contact with the slope (incline). That is, the operator can bring the bucket 6 into contact with the slope (incline) by performing the slewing operation without pressing the switch NS.

[0129] exist Figure 7 In the example shown, the controller 30 calculates the height of the bucket 6 (or the posture of the digging attachment AT) and the turning radius during rotation at a predetermined control cycle. Based on the height of the bucket 6 (or the posture of the digging attachment AT) and the turning radius calculated during rotation, the controller 30 calculates the distance from a predetermined position of the digging attachment AT to the design surface at a predetermined control cycle. The controller 30 compares the distance calculated at the predetermined control cycle from the predetermined position of the digging attachment AT to the design surface with preset distances X1 and X2. Furthermore, when the calculated distance is lower than distance X1, the controller 30 begins to decelerate the rotation of the upper rotating body 3. Specifically, the controller 30 decelerates the rotation of the upper rotating body 3 at a predetermined deceleration. The predetermined deceleration can be constant or variable. Furthermore, when the calculated distance becomes distance X2 (< distance X1), the controller 30 stops the rotation of the upper rotating body 3. Additionally, Figure 7 Point P1 represents the position of the specified part at the start of deceleration during the rotational motion. Furthermore, Figure 6 and Figure 7 Point P2 in the diagram represents the position of the specified location when the rotational motion stops. Furthermore, Figure 6 and Figure 7 Point P3 in the diagram represents the estimated position of a specified part when the bucket 6 contacts the design surface, assuming the rotation continues even without a stop caused by automatic control. Specifically, the estimated position of the contact point corresponds to the position of the intersection between the rotation path followed by the specified point in the bucket 6 and the design surface when the rotation continues.

[0130] In addition, Figure 7 In the example shown, the controller 30 is configured such that the distance X1, serving as a threshold, varies according to the working radius R1. Specifically, the larger the working radius R1, the larger the distance X1 is set. This is because a larger working radius R1 results in a larger inertial torque of the digging auxiliary device AT, making it more difficult to stop the slewing motion. For the same reason, the controller 30 can be configured such that the distance X2, serving as a threshold, varies according to the working radius R1. However, the controller 30 can also be configured to keep the distance X1 constant regardless of the working radius R1.

[0131] Alternatively, the controller 30 can be configured such that the distance X1, which serves as a threshold, varies according to changes in the posture of the excavating attachment AT. For example, the larger the boom angle θ1, the smaller the distance X1 can be set; the smaller the stick angle θ2, the smaller the distance X1 can be set.

[0132] Alternatively, the controller 30 can be configured such that the distance X1, which serves as a threshold, varies according to changes in the rotational speed. For example, the greater the rotational speed, the larger the distance X1 can be set.

[0133] Furthermore, if the rotational speed of the upper rotating body 3 is below a specified speed, the controller 30 may stop the upper rotating body 3 without slowing it down, rather than by decelerating its rotational motion.

[0134] Furthermore, the specified condition may be, for example, whether the angle (hereinafter referred to as the "calculated angle") formed between the imaginary line EL representing the extension direction of the slope in the top view and the centerline of the excavator 100 in the top view exceeds a specified angle.

[0135] exist Figure 7 In the example shown, the controller 30 calculates the height of the bucket 6 (or the posture of the digging attachment AT) and the turning radius during rotation at a predetermined control cycle. Based on the height of the bucket 6 (or the posture of the digging attachment AT) and the turning radius calculated during rotation, the controller 30 calculates the rotation angle from a predetermined position of the digging attachment AT to the design surface at a predetermined control cycle. The controller 30 compares the rotation angle calculated at the predetermined control cycle from the predetermined position of the digging attachment AT to the design surface with preset angles α1 and α2.

[0136] exist Figure 7 In the example shown, angles α1 and α2 are the angles formed between the imaginary line EL, representing the extension direction of the slope in a top-down view, and the centerline of the excavator 100 in a top-down view. Figure 7 In the example shown, the calculated angle is the angle that becomes the maximum angle (90 degrees) when the excavator 100 is directly facing the slope (slope), and the closer the excavator 100 is to the direct facing state, the closer the calculated angle is to the maximum angle. Therefore, angles α1 and α2 are set to angles less than 90 degrees.

[0137] Furthermore, when the calculated angle exceeds angle α1, the controller 30 begins to decelerate the rotation of the upper rotating body 3. Specifically, the controller 30 decelerates the rotation of the upper rotating body 3 at a predetermined deceleration. This predetermined deceleration can be constant or variable. And, when the calculated angle becomes angle α2 (> angle α1), the controller 30 stops the rotation of the upper rotating body 3. Additionally, Figure 7 The calculated angle α3 represents the angle at which the excavator 100 faces the slope (incline) in order to perform the next excavation operation. The state of the excavator 100 when it faces the slope (incline) is defined as the state where the operating plane of the excavation attachment AT includes the direction perpendicular to the design surface (slope) (normal direction). The operating plane of the excavation attachment AT can be, for example, an imaginary plane including the longitudinal centerline of the excavation attachment AT.

[0138] Furthermore, the controller 30 can be configured such that, if it is determined that the bucket 6 is not in contact with the design surface, the rotation motion is stopped automatically, thereby stopping the rotation motion of the upper rotating body 3 when it is facing the slope. Thus, when the controller 30 determines that the bucket 6 is not in contact with the design surface, the operator of the excavator 100 does not need to worry about the contact between the bucket 6 and the design surface; simply by tilting the left operating lever 26L to the left to the desired amount, the excavator 100 can be made to face the slope. This is because regardless of the determination of whether the bucket 6 is in contact with the design surface, the rotation motion of the upper rotating body 3 is appropriately stopped.

[0139] With the above structure, the controller 30 does not suddenly stop the slewing motion when the specified conditions are met, but gradually stops the slewing motion, so the operator of the excavator 100 will not feel uncomfortable.

[0140] Furthermore, the controller 30 is configured to automatically stop the slewing motion regardless of the amount of operation of the left operating lever 26L, in order to avoid contact between the bucket 6 and the design surface. That is, even if the operator of the excavator 100 tilts the left operating lever 26L to the left slewing direction, the left slewing motion can be automatically stopped.

[0141] Furthermore, in Figure 7 In the example shown, the controller 30 automatically stops the slewing motion to avoid contact between the bucket 6 and the design surface, but does not automatically stop other actions. For example, when the operator of the excavator 100 performs a combined operation including left slewing and boom lifting, and certain conditions are met, the controller 30 automatically stops the left slewing motion, but does not automatically stop the boom lifting motion.

[0142] Specifically, when the calculated distance is lower than distance X1 during a combined operation involving left slewing and boom lifting by the operator, the controller 30 automatically decelerates or stops the left slewing motion, but does not automatically decelerate or stop the boom lifting motion. Therefore, the boom 4 continues to rise according to the boom lifting operation performed by the operator. Furthermore, if the boom 4 rises, the calculated distance again exceeds distance X1 due to the inclination (uphill slope) of the ramp. If the calculated distance again exceeds distance X1, the controller 30 releases the deceleration or stopping of the slewing motion based on automatic control. At this time, if the operator continues the left slewing operation, the controller 30 restarts the unrestricted left slewing motion according to this left slewing operation. As a result, the controller 30 can maintain a roughly constant distance between a predetermined point in the bucket 6 and the ramp while simultaneously slewing the upper slewing body 3 to the left and raising the boom 4 until the combined operation performed by the operator is interrupted. Additionally, the combined operation may also include other operations such as stick retraction.

[0143] Alternatively, if the calculated distance is lower than distance X1 when the operator performs a combined operation including left slewing and stick retraction, the controller 30 automatically decelerates or stops the left slewing action, but does not automatically decelerate or stop the stick retraction action. Therefore, the stick 5 continues to retract according to the stick retraction operation performed by the operator. Furthermore, if the stick 5 retracts, the calculated distance again exceeds distance X1 due to the inclination (uphill slope) of the ramp. If the calculated distance again exceeds distance X1, the controller 30 releases the deceleration or stopping of the slewing action based on automatic control. At this time, if the operator continues the left slewing operation, the controller 30 restarts the unrestricted left slewing action according to this left slewing operation. As a result, the controller 30 can maintain a substantially constant distance between a predetermined point in the bucket 6 and the ramp (slope) while simultaneously slewing the upper slewing body 3 to the left and retracting the stick 5 until the combined operation performed by the operator is interrupted. Additionally, the combined operation may also include other operations such as bucket retraction.

[0144] Alternatively, if the calculated distance is less than distance X1 when the operator performs a combined operation including a left turn and a walking operation, the controller 30 automatically decelerates or stops the left turn, but does not automatically decelerate or stop the walking operation in the direction away from the slope. Therefore, the lower walking body 1 continues to move away from the slope according to the walking operation performed by the operator. Furthermore, if the lower walking body 1 moves away from the slope, the calculated distance again exceeds distance X1. If the calculated distance again exceeds distance X1, the controller 30 releases the deceleration or stopping of the turn operation based on automatic control. At this time, if the operator continues the left turn operation, the controller 30 restarts the unrestricted left turn operation according to that left turn operation. As a result, the controller 30 is able to keep the distance between a specified point in the bucket 6 and the slope (slope) approximately constant while rotating the upper slewing body 3 to the left and moving the lower traveling body 1 away from the slope (slope) until the combined operation performed by the operator is interrupted.

[0145] On the other hand, when the lower traveling body 1 moves towards the slope (incline), if the calculated distance is less than distance X1 when the operator performs a combined operation including left turn and travel, the controller 30 automatically slows down or stops the left turn and also automatically slows down or stops the travel movement towards the slope (incline). This is because simply stopping the turn operation is insufficient to avoid contact between the bucket 6 and the slope (incline).

[0146] Furthermore, when the operator performs the slewing operation alone and no other operations are performed by the operator, the controller 30 will not automatically control the excavation attachment to avoid contact between the bucket 6 and the slope (incline).

[0147] For example, when the operator performs a left turn operation alone and does not perform a boom lifting operation, even if the calculated distance is less than distance X1, the controller 30 will not automatically raise the boom 4 to avoid contact between the bucket 6 and the slope (incline). In this case, the controller 30 only stops the left turn operation automatically, that is, only completely stops the movement of the excavator 100.

[0148] Furthermore, when the operator performs a left turn operation alone and without performing a stick retraction operation, the controller 30 will not automatically retract the stick 5 to avoid contact between the bucket 6 and the slope (incline). Similarly, when the operator performs a left turn operation alone and without performing a bucket retraction operation, the controller 30 will not automatically retract the bucket 6 to avoid contact between the bucket 6 and the slope (incline).

[0149] As described above, the excavator 100 according to the embodiments of the present invention includes: a lower traveling body 1; an upper rotating body 3 rotatably mounted on the lower traveling body 1; and an auxiliary device mounted on the upper rotating body 3. Furthermore, the excavator 100 is configured such that, when the upper rotating body 3 rotates, if interference between the auxiliary device and a stop surface (e.g., the auxiliary device crossing the stop surface) is anticipated (e.g., the auxiliary device traverses the stop surface), the rotation of the upper rotating body 3 is automatically decelerated or stopped. For example, the controller 30, as an example of an excavator control device mounted on the excavator 100, can be configured such that, when the upper rotating body 3 rotates, if interference between the auxiliary device and a stop surface (e.g., the auxiliary device traverses the stop surface) is anticipated (e.g., the auxiliary device traverses the stop surface), the rotation of the upper rotating body 3 is automatically decelerated or stopped. Alternatively, the excavator control device can be another control device different from the controller 30. Specifically, the control device for the excavator can be a control device that is detachably installed in the cab 10, or it can be a movable control device. Furthermore, the control device for the excavator can also be a control device capable of performing a portion of the functions of the controller 30.

[0150] The stopping surface is, for example, an imaginary surface set in a reference coordinate system, typically a design surface. Alternatively, the stopping surface can be a plane or a curved surface. Furthermore, the stopping surface can be a complex surface composed of multiple planes, multiple curved surfaces, or combinations thereof. The stopping surface can also be an imaginary surface that can be arbitrarily set by the operator of the excavator 100 via the information input device 72. Additionally, the stopping surface can be an imaginary surface generated based on information identified by the spatial recognition device 70.

[0151] This structure enables more appropriate automatic control of the excavator 100. This is because it prevents auxiliary devices from erroneously crossing (digging into) the stopping surface (design surface) due to slewing motion. Specifically, this structure automatically decelerates or stops the slewing motion corresponding to the operator's manual slewing operation on the excavator 100, thus preventing damage to the stopping surface caused by incorrect or inappropriate slewing operations by the operator. Therefore, this structure supports the operator in accurately forming construction surfaces such as ramps according to the design surface.

[0152] Furthermore, the excavator 100 can also be configured such that when the rotation of the upper slewing body 3 is slowed down or stopped, the boom lifting operation based on automatic control is prohibited. In this structure, even if the operator does not perform a boom lifting operation, it is possible to prevent the boom 4 from being forcibly raised to avoid contact between the auxiliary device and the stopping surface. Therefore, this structure can prevent the excavator 100 from becoming unstable (the excavator 100 is about to overturn) or the boom 4 from coming into contact with the power lines erected above the excavator 100.

[0153] The excavator 100 can be configured to reduce the rotation of the upper rotating body 3 when a predetermined part of the auxiliary device is within a pre-set deceleration zone. For example, in Figure 7 In the example shown, if a predetermined point in the bucket 6, an example of a designated part of the auxiliary device, reaches point P1, the controller 30 is configured to decelerate the rotation of the upper slewing body 3. Point P1 is a point on the slewing track followed by the predetermined point during the slewing operation, and is a point whose distance (along the slewing track) from another point P3 on the slewing track is equal to a threshold (distance X1). Point P3 is the intersection of the slewing track and the stopping surface (design surface). Furthermore, point P2, located between point P1 and point P3 on the slewing track, is the point where the predetermined point in the bucket 6 is located when the rotation of the upper slewing body 3 is stopped. The controller 30 automatically stops the rotation of the upper slewing body 3 so that the predetermined point in the bucket 6 is located at point P2 when the rotation of the upper slewing body 3 is stopped. At this time, the deceleration region, for example, represents the interval between point P1 and point P2 on the slewing track.

[0154] With this structure, the excavator 100 can smoothly stop the upper rotating body 3 before it crosses the stopping surface at a designated location of the auxiliary device. Therefore, the excavator 100 can prevent its posture from becoming unstable due to the sudden stop of the upper rotating body 3.

[0155] The excavator 100 can be configured such that the deceleration zone varies depending on the posture of the auxiliary device. Specifically, the excavator 100 can be configured such that the smaller the working radius of the auxiliary device, the smaller the width of the deceleration zone. For example, in Figure 7 In the example shown, the excavator 100 is configured such that the larger the operating radius R1, the larger the deceleration zone. This structure has the following effect: the greater the inertial torque of the auxiliary device, the earlier the deceleration of the slewing motion can begin, thus ensuring that the upper rotating body 3 can reliably stop at the desired position. Furthermore, this structure has the following effect: the smaller the inertial torque of the auxiliary device, the later the deceleration of the slewing motion can begin, thus preventing excessive premature deceleration of the upper rotating body 3.

[0156] The stopping surface can be obtained as design information or by a camera device. Specifically, the stopping surface can be an imaginary surface generated based on data related to the design surface stored in a non-volatile storage device in the controller 30, or it can be an imaginary surface generated based on image data acquired by a camera device, such as a spatial recognition device 70. With this structure, the operator of the excavator 100 can quickly and easily obtain the stopping surface.

[0157] When the lower traveling body 1 is traveling, the excavator 100 can decelerate or stop the lower traveling body 1 if it anticipates that the auxiliary device will cross the stopping surface. For example, the controller 30 can be configured such that, during slope trimming operations, when simultaneously performing a traveling motion to bring the lower traveling body 1 closer to the slope (incline) and a rotating motion to bring the bucket 6 closer to the slope (incline), it can decelerate or stop the lower traveling body 1 if it anticipates contact between the bucket 6 and the stopping surface (design surface). This is because stopping the rotating motion alone is sometimes insufficient to avoid contact between the bucket 6 and the design surface. With this configuration, even when performing a combined operation including traveling and rotating operations, the excavator 100 can reliably avoid contact between the bucket 6 and the design surface by stopping at least one of the traveling motion of the lower traveling body 1 and the rotating motion of the upper rotating body 3.

[0158] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Various modifications or substitutions can be applied to the above embodiments without departing from the scope of the present invention. Furthermore, features described separately can be combined as long as they do not create technical contradictions.

[0159] This application claims priority based on Japanese Patent Application No. 2021-047751, filed on March 22, 2021, the entire contents of which are incorporated herein by reference.

[0160] Symbol Explanation

[0161] 1-Lower traveling body, 1C-Track, 1CL-Left track, 1CR-Right track, 2-Swing mechanism, 2A-Swing hydraulic motor, 2M-Travel hydraulic motor, 2ML-Left travel hydraulic motor, 2MR-Right travel hydraulic motor, 3-Upper slewing body, 4-Boom, 5-Stick, 6-Bucket, 7-Boom cylinder, 8-Stick cylinder, 9-Bucket cylinder, 10-Cab, 11-Engine, 13-Regulator, 14-Main pump, 15-Pilot pump, 17-Control valve unit, 18-Throttle, 19-Control pressure sensor, 26-Operating device, 26D-Travel lever, 26DL-Left travel lever, 26DR-Right travel lever, 26L-Left operating lever, 26R-Right operating lever, 28-Discharge pressure sensor, 29, 29DL, 29DR, 29LA, 29LB, 29RA, 29RB-Operating device Sensors, 30-Controller, 30A-Position Calculation Unit, 30B-Track Acquisition Unit, 30C-Automatic Control Unit, 31, 31AL~31DL, 31AR~31DR-Proportional Valves, 40-Intermediate Bypass Pipeline, 42-Parallel Pipeline, 70-Spatial Recognition Device, 70F-Front Side Sensor, 70B-Rear Side Sensor, 70L-Left Side Sensor, 70R-Right Side Sensor, 71-Orientation Detection Device, 72-Information Input Device, 73-Position Measurement Device, 75-Control Panel, 100-Excavator, 171~176-Control Valves, AT-Excavation Accessories, D1-Display Device, D2-Sound Output Device, NS-Switch, S1-Boom Angle Sensor, S2-Stick Angle Sensor, S3-Bucket Angle Sensor, S4-Body Tilt Sensor, S5-Slewing Angular Velocity Sensor.

Claims

1. An excavator, comprising: Lower walking body; The upper rotating body is rotatably mounted on the lower traveling body; and An auxiliary device is installed on the upper rotating body. When the upper rotating body rotates, if interference between the auxiliary device and the controlled object surface is anticipated, the rotation of the upper rotating body is automatically decelerated or stopped. When the upper slewing body rotates, if interference between the auxiliary device and the controlled object surface is anticipated, the boom lifting action based on automatic control is prohibited. The automatic control, under the condition that the specified start conditions are met, causes a specified part of the auxiliary device to move along the target track. The automatic control includes the control to stop the rotation of the upper rotating body when the upper rotating body is facing the surface of the controlled object.

2. The excavator according to claim 1, wherein, When the designated part of the auxiliary device is located within a pre-set deceleration zone, the rotation of the upper rotating body is decelerated.

3. The excavator according to claim 2, wherein, The deceleration zone varies depending on the posture of the auxiliary device.

4. The excavator according to claim 2, wherein, The smaller the operating radius of the auxiliary device, the smaller the width of the deceleration zone.

5. The excavator according to claim 1, wherein, The controlled object surface is acquired as design information or by a camera device.

6. The excavator according to claim 1, wherein, When the lower walking body is moving, if interference between the auxiliary device and the surface of the controlled object is anticipated, the lower walking body is decelerated or stopped.

7. A control device for an excavator, for controlling an excavator, the excavator comprising: a lower traveling body; an upper rotating body rotatably mounted on the lower traveling body; and an auxiliary device installed on the upper rotating body, the control device for the excavator being configured as follows: When the upper rotating body rotates, if interference between the auxiliary device and the controlled object surface is anticipated, the rotation of the upper rotating body is automatically decelerated or stopped. When the upper slewing body rotates, if interference between the auxiliary device and the controlled object surface is anticipated, the boom lifting action based on automatic control is prohibited. The automatic control, under the condition that the specified start conditions are met, causes a specified part of the auxiliary device to move along the target track. The automatic control includes the control to stop the rotation of the upper rotating body when the upper rotating body is facing the surface of the controlled object.

8. The control device for an excavator according to claim 7, wherein, When the designated part of the auxiliary device is located within a pre-set deceleration zone, the rotation of the upper rotating body is decelerated.

9. The control device for an excavator according to claim 8, wherein, The deceleration zone varies depending on the posture of the auxiliary device.

10. The control device for an excavator according to claim 8, wherein, The smaller the operating radius of the auxiliary device, the smaller the width of the deceleration zone.

11. The control device for an excavator according to claim 7, wherein, The controlled object surface is acquired as design information or by a camera device.

12. The control device for an excavator according to claim 7, wherein, When the lower walking body is moving, if interference between the auxiliary device and the surface of the controlled object is anticipated, the lower walking body is decelerated or stopped.

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