Construction machine

Abstract

To improve reliability of work using machine guidance and machine control by easily and accurately grasping changes in a length dimension of an excavation claw.SOLUTION: A hydraulic shovel 1 comprises a camera capturing a bucket 10 of a work device 7. Then, a controller 19 analyzes an image of the bucket 10 captured by the camera 18 to calculate a length dimension L1 (L0) of an excavation claw 12, and reflects an amount of change of the calculated length dimension L1 (L0) of the excavation claw 12 in a tiptoe position calculation.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a construction machine such as a hydraulic excavator that performs work by utilizing machine guidance and machine control. [Background technology]

[0002] Generally, a hydraulic excavator, which is a typical example of a construction machine, includes a self-propelled lower body and an upper rotating body rotatably mounted on the lower body. A working device having a bucket is rotatably provided on the front side of the upper rotating body, and this working device is used for civil engineering work such as excavating soil and sand.

[0003] In recent years, information-based construction using ICT (Information and Communication Technology) has been introduced into civil engineering work. This information-based construction includes machine guidance (MG) and machine control (MC) that use total stations (TS) and global navigation satellite systems (GNSS). Machine guidance (MG) calculates the tip position of the excavation claws of the hydraulic excavator bucket, calculates the calculated tip position of the excavation claws of the bucket, and calculates the difference between the calculated tip position of the excavation claws of the bucket and the design value (three-dimensional design data) from the construction information, and provides this to the operator to support the operation of the hydraulic excavator. Machine control (MC) calculates the tip position of the excavation claws of the hydraulic excavator bucket, and automatically controls the machine in real time to perform construction so that the tip position of the excavation claws of the bucket follows the design value (three-dimensional design data).

[0004] A hydraulic excavator that performs machine guidance and machine control is equipped with a posture detection sensor that detects the posture of a working implement, and a controller that performs a toe position calculation to calculate the tip position of the bucket's digging claws based on the posture of the working implement detected by the posture detection sensor (Patent Document 1).

[0005] However, the digging claws provided on the bucket may become worn or damaged due to impacts and friction during excavation, resulting in a shortened length. In addition, when replacing the digging claws, the length dimension changes whether a new digging claw is attached or a used digging claw is attached. If the length dimension of the digging claws changes in this way, there is a risk of a decrease in work accuracy when work is performed using claw tip position calculations.

[0006] Some hydraulic excavators that perform work using the tip position calculation are equipped with a function to calculate changes in the length dimension of the excavation claw, for example, the amount of wear of the excavation claw. This hydraulic excavator detects the movement dimension of any coordinate by rotating the bucket with the tip of the excavation claw positioned on the ground, and calculates the amount of wear of the excavation claw (Patent Document 2). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent Publication No. 2021-4540 [Patent Document 2] Patent No. 6401296 Summary of the Invention [Problem to be solved by the invention]

[0008] However, because the change in coordinates due to wear of the excavation claws is small, it is necessary to rotate the bucket so that the position of the tip of the excavation claw does not shift. This requires a solid ground on which the excavation claws can be pressed, and also requires skilled operation techniques for the work device. Therefore, it becomes difficult to obtain an accurate wear amount of the excavation claws, which causes a problem of reduced reliability of work using machine guidance and machine control.

[0009] An object of the present invention is to provide a construction machine that can improve the reliability of operations using machine guidance and machine control by easily and accurately grasping changes in the length dimension of the digging claws. [Means for solving the problem]

[0010] The present invention relates to a construction machine comprising a vehicle body, a working device provided on the vehicle body and having a bucket at its tip, an attitude detection sensor for detecting the attitude of the working device, and a controller for performing a tip position calculation to calculate the tip position of the excavation claw of the bucket based on the attitude of the working device detected by the attitude detection sensor.The construction machine is provided with a camera for photographing the bucket, and the controller analyzes an image of the bucket taken by the camera to calculate the length dimension of the excavation claw, and reflects the calculated amount of change in the length dimension of the excavation claw in the tip position calculation. Effect of the Invention

[0011] According to the present invention, changes in the length dimension of the digging claws can be easily and accurately grasped, thereby improving the reliability of work using machine guidance and machine control. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a left side view showing a hydraulic excavator according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a left side view showing the working device in FIG. [Diagram 3] FIG. 13 is a left side view showing the other end of the bucket and the camera. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. 2 is a configuration diagram for performing machine guidance. [Figure 7] 11 is an explanatory diagram showing an image of the other end side (digging claw) of the bucket captured by a camera. FIG. [Figure 8] 10 is a flowchart showing a procedure for calculating a toe position. [Figure 9] FIG. 11 is a configuration diagram for performing machine guidance according to a second embodiment of the present invention. [Figure 10]10 is a flowchart showing a flow for performing machine guidance according to the second embodiment. [Figure 11] FIG. 11 is a configuration diagram for performing machine guidance according to a third embodiment of the present invention. [Figure 12] 13 is a flowchart showing a procedure for performing a toe position calculation according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of a construction machine according to the present invention will be described in detail with reference to the accompanying drawings, taking as an example a case where the construction machine is applied to a crawler-type hydraulic excavator. In the embodiment, the extension direction of the working device is the front-rear direction, and the width direction of the working device perpendicular to the extension direction is the left-right direction.

[0014] Figures 1 to 8 show a first embodiment. In Figure 1, a hydraulic excavator 1, which is a representative example of a construction machine, is equipped with a self-propelled crawler-type lower traveling body 2, an upper rotating body 3 that is rotatably mounted on the lower traveling body 2 and forms a vehicle body together with the lower traveling body 2, and a working device 7 (described below) that is rotatably attached to the front side of the upper rotating body 3. The hydraulic excavator 1 travels on the lower traveling body 2 at a work site, and performs work such as excavating earth and sand by rotating the upper rotating body 3 while rotating the working device 7.

[0015] The upper rotating body 3 has a rotating frame 4 serving as a base, and a boom 8 of a working device 7 and the like are rotatably attached to the front middle part in the left-right direction of the rotating frame 4. The upper rotating body 3 has a cab 5 at the front left part of the rotating frame 4.

[0016] The cab 5 is formed in a box shape that defines the driver's compartment, and inside the cab 5 is provided a driver's seat (not shown) where an operator sits. A travel lever and pedal device (not shown) that controls the travel operation of the hydraulic excavator 1 is provided in front of the driver's seat. On both the left and right sides of the driver's seat, work lever devices (not shown) that control the revolving operation of the upper revolving body 3 and the rotational operation of the work device 7 are provided. Furthermore, inside the cab 5, a monitor 6 (display device of the present invention) that displays information such as the status of the equipment (engine, actuators, sensors, etc.) mounted on the hydraulic excavator 1, the status of work, and work instructions, and a controller 18 described below are provided.

[0017] As shown in Figures 1 and 2, the working device 7 is rotatably attached to the front side of the upper rotating body 3. The working device 7 includes a boom 8, an arm 9, a bucket 10, a bucket link 13, a boom cylinder 14, an arm cylinder 15, and a bucket cylinder 16, which will be described later. The working device 7 rotates the boom 8, the arm 9, the bucket 10, etc., by appropriately extending and retracting the boom cylinder 14, the arm cylinder 15, and the bucket cylinder 16, to perform work such as excavating earth and sand. The working device 7 is also provided with posture detection sensors 17A, 17B, and 17C, which will be described later, for detecting the postures of the boom 8, the arm 9, and the bucket 10.

[0018] The boom 8 is rotatably attached to the revolving frame 4 of the upper revolving body 3. When the boom 8 is tilted forward, it has a lower surface 8A located on the lower side, an upper surface 8B located on the upper side, and side surfaces 8C located on both the left and right sides (only the left side is shown). The boom 8 is formed as a rectangular tube structure with the middle part in the length direction bent into an inverted V shape.

[0019] One end of the boom 8 is rotatably attached to the revolving frame 4 by using a connecting pin (not shown). One end of an arm 9 is attached to the other end of the boom 8. A camera 18 (described later) is attached to the underside 8A of the boom 8 at a position facing the other end of the bucket 10 (near the middle part in the length direction) when the arm 9 and bucket 10 are folded up. Furthermore, an arm cylinder bracket 8D is provided on the upper surface 8B, located near the middle part in the length direction.

[0020] The arm 9 is rotatably attached to the other end of the boom 8. The arm 9 is formed as a linear rectangular tube structure. One end of the arm 9 is rotatably attached to the other end of the boom 8 using a connecting pin 9A extending in the left-right direction. An arm cylinder bracket 9B is provided at one end of the arm 9. Also, a bucket cylinder bracket 9C is provided at one end of the arm 9. One end of a bucket 10 is attached to the other end of the arm 9.

[0021] The bucket 10 is rotatably attached to the other end of the arm 9. The bucket 10 has a bucket body 11, the inside of which is a space for storing soil and sand, and a plurality of excavation claws 12 provided on the other end side of the bucket body 11.

[0022] The bucket body 11 stores excavated soil and sand. The bucket body 11 has a bottom plate 11A having a concave curved shape, and a left plate 11B and a right plate 11C (see FIG. 7) fixed to both the left and right sides of the bottom plate 11A, and a storage space for soil and sand is formed by the bottom plate 11A, the left plate 11B, and the right plate 11C. A pair of brackets 11D is provided at one end of the bottom plate 11A with a gap in the left-right direction. A flat cutting edge 11E that is thicker than the bottom plate 11A is provided at the other end of the bottom plate 11A. The pair of brackets 11D of the bucket body 11 are rotatably attached to the end of the other end of the arm 9 by using a connecting pin 11F extending in the left-right direction. A front link 13B of the bucket link 13 is rotatably attached to the pair of brackets 11D.

[0023] The excavation claws 12 are provided protruding from the other end of the cutting edge 11E located on the other end side of the bucket body 11. A plurality of the excavation claws 12, for example five in this embodiment, are arranged side by side in the left-right direction on the cutting edge 11E. The excavation claws 12 are composed of an adapter 12A, a point 12B, and a fixing pin 12C, which will be described later.

[0024] The five adapters 12A are arranged at regular intervals in the left-right direction on the cutting edge 11E of the bucket body 11. The adapters 12A are fixed to the cutting edge 11E by welding while sandwiching the cutting edge 11E. In addition, a point 12B is detachably attached to the tip (other end) of the adapter 12A protruding from the cutting edge 11E.

[0025] The five points 12B are formed as replaceable claws. The base end of the point 12B is thicker than the tip end. The base end of the point 12B is recessed to fit over the tip of the adapter 12A.

[0026] The point 12B can be fixedly attached to the adapter 12A by driving a fixing pin 12C in the thickness direction of the cutting edge 11E, spanning the recess of the point 12B and the tip of the adapter 12A, with the recess on the base end side being placed (fitted) over the tip of the adapter 12A. The point 12B can be removed from the adapter 12A by punching out the fixing pin 12C in the opposite direction to the driving direction. This allows the point 12B to be replaced if it becomes significantly worn or broken.

[0027] Here, as shown in FIG. 7, the five excavation claws 12 have an overall length dimension (total length dimension) from the base end 12A1 of the adapter 12A on the opposite side to the point 12B to the tip end 12B1 of the point 12B. The total length dimension of the excavation claw 12 is changed from the reference length dimension L2 described later, which is the total length dimension of a new excavation claw 12, to a calculated length dimension L1 described later through wear and damage. The base end 12A1 of the adapter 12A is a fixed point (a point that does not change even if wear or damage occurs) in the image captured by the camera 18 shown in FIG. 7. When measuring the change in the total length dimension of the excavation claw 12 due to wear and damage, specifically, how much the tip end 12B1 of the current point 12B has become shorter compared to the tip end 12B2 of the new point 12B, an arbitrary point (in this embodiment, the base end 12A1 of the adapter 12A) is set as a reference in the length direction of the excavation claw 12, and the dimension from the arbitrary point to the tip end 12B1 of the point 12B is measured. The arbitrary point serving as the reference may be any point that does not change even if wear or damage occurs, and may be the base end of the fixing pin 12C or the point 12B.

[0028] When measuring the length dimension of the digging claw 12 (point 12B) that changes due to wear and tear, i.e., the calculated length dimension L1, the image captured by the camera 18 is analyzed to clarify the outer edge (contour) of the digging claw 12, and the digging claw 12 is extracted from the image data. At this time, since the base end 12A1 of the adapter 12A protrudes from the flat cutting edge 11E, the boundary with the cutting edge 11E is clear, and the outer edge of the digging claw 12 can be accurately extracted (distinguished).

[0029] The bucket link 13 is provided between the other end of the arm 9 and the bucket 10. The bucket link 13 is composed of a rear link 13A having one end connected to the tip side of the arm 9, and a front link 13B having one end connected to the other end of the rear link 13A and the other end connected to a bracket 11D of the bucket body 11.

[0030] The boom cylinders 14 are provided on either side of the boom 8 (only the left side is shown). One end of the boom cylinder 14 in the length direction is rotatably attached to the revolving frame 4, and the other end is rotatably attached to a side surface 8C of the boom 8. The two boom cylinders 14 extend and retract to rotate the boom 8 in the front-to-rear and up-down directions relative to the upper revolving body 3 (revolving frame 4).

[0031] The arm cylinder 15 is provided between the boom 8 and the arm 9. One end of the arm cylinder 15 in the longitudinal direction is rotatably attached to an arm cylinder bracket 8D of the boom 8, and the other end is rotatably attached to an arm cylinder bracket 9B of the arm 9. The arm cylinder 15 rotates the arm 9 in the front-to-back direction or up-down direction relative to the boom 8 by extending and retracting.

[0032] The bucket cylinder 16 is provided between the arm 9 and the bucket link 13. One end of the bucket cylinder 16 in the longitudinal direction is rotatably attached to a bucket cylinder bracket 9C of the arm 9, and the other end is rotatably attached to a connection portion between the rear link 13A and the front link 13B. The bucket cylinder 16 rotates the bucket 10 in the front-rear direction and the up-down direction relative to the arm 9 by extending and retracting.

[0033] The attitude detection sensors 17A, 17B, and 17C are provided on the working device 7 and detect the attitude of the working device 7. The attitude detection sensors 17A, 17B, and 17C are connected to an input section of a controller 19 described below. The attitude detection sensors 17A, 17B, and 17C detect the angles of the boom 8, the arm 9, and the bucket 10, and output the detection data to the controller 19. The attitude detection sensors 17A, 17B, and 17C include angle sensors provided between the revolving frame 4 and the boom 8, between the boom 8 and the arm 9, and between the arm 9 and the bucket 10, and stroke sensors that detect the extension / retraction states (length dimensions) of the boom cylinder 14, the arm cylinder 15, and the bucket cylinder 16, and the like.

[0034] The working device 7 configured in this manner greatly extends the arm cylinder 15 and the bucket cylinder 16, and uses the posture detection sensors 17B, 17C to place the arm 9 and the bucket 10 in a predetermined posture. As a result, the bucket 10 is positioned facing the underside 8A of the boom 8. In the following description, the posture in which the bucket 10 faces the underside 8A of the boom 8 is referred to as the "specific position."

[0035] The camera 18 is provided on the underside 8A of the boom 8. The camera 18 is attached to the underside 8A of the boom 8 so as to be rotatable in the front-rear direction. The camera 18 photographs the other end side of the bucket 10 including the excavation claws 12 when the bucket 10 is placed in a specific position (the position shown in Figs. 1 to 3) facing the underside 8A of the boom 8. At this time, the camera 18 photographs an area including five (two or more) excavation claws 12. Specifically, the camera 18 photographs the area shown in Fig. 7.

[0036] As shown in FIG. 4 and FIG. 5, the camera 18 is composed of a fixed member 18A attached to the lower surface 8A of the boom 8, a rotating member 18C connected to the fixed member 18A via a bolt 18B so as to be rotatable in the front-rear direction, and a camera body 18D provided on the rotating member 18C. The camera body 18D is connected to a controller 19, which will be described later, by wire or wirelessly. The camera 18 can be made to face the other end side (cutting edge 11E, excavation claw 12, etc.) of the bucket 10 by loosening the bolt 18B and rotating the rotating member 18C, and can be fixed by tightening the bolt 18B at this position. Therefore, even if the arm 9 or the bucket 10 is replaced, it can be handled by rotating the rotating member 18C. The position where the camera body 18D faces the other end side of the bucket 10 is a position where the optical axis of the camera body 18D is perpendicular or approximately perpendicular to the cutting edge 11E.

[0037] As shown in Fig. 6, the controller 19 is provided, for example, in the cab 5 of the upper revolving body 3. The controller 19 includes, for example, a calculation unit (not shown) made up of a microcomputer, a storage unit 19A made up of semiconductor memory such as ROM or RAM, an input unit for receiving signals, and an output unit for transmitting signals (none of which are shown). The input unit of the controller 19 is connected to the attitude detection sensors 17A, 17B, and 17C, the camera body 18D of the camera 18, an engine switch, and various sensors (none of which are shown). On the other hand, the output unit of the controller 19 is connected to the monitor 6 in the cab 5, etc.

[0038] The storage unit 19A of the controller 19 has a processing program for machine guidance that notifies the difference between the coordinates of the design data input in advance and the current coordinates calculated using a global navigation satellite system (GNSS), a total station (TS), etc., analysis of the image transmitted from the camera 18 (extraction of the excavation claw 12), calculation of the length dimension L1 of the excavation claw 12 based on the analyzed image, and numerical correction of the machine guidance that reflects the dimensional change of the excavation claw 12 due to wear, etc. The storage unit 19A also stores a reference value of the length dimension of the excavation claw 12, which in this embodiment is the reference length dimension L2 of the excavation claw 12 when a new point 12B is attached. This reference length dimension L2 of the excavation claw 12 is used when performing numerical correction of the machine guidance.

[0039] The controller 19 analyzes the image of the excavation claw 12 of the bucket 10 captured by the camera 18 to calculate the length dimension of the excavation claw 12 of the bucket 10, and reflects the calculated amount of change in the length dimension of the excavation claw 12 of the bucket 10 in the tip position calculation. In addition, the controller 19 corrects the reference length dimension L2 serving as a reference value based on the length dimension L1 of the excavation claw 12 calculated by analyzing the image of the excavation claw 12 captured by the camera 18, and performs the tip position calculation based on the corrected reference value length dimension L2, and causes the monitor 6 to display information on the calculated tip position (tip portion 12B1) of the excavation claw 12.

[0040] An example of a means for measuring the change in the overall length of the excavation claw 12 due to wear or damage, specifically, how much the current point 12B has become shorter compared to a new point 12B, will be described below. The image from the camera 18 is analyzed to calculate the length L1 of the excavation claw 12, and this calculated length L1 is compared with the reference length L2 of the excavation claw 12 with the new point 12B attached, and the difference ΔL shortened due to wear or the like is calculated (L2-L1=ΔL).

[0041] The hydraulic excavator 1 according to this embodiment has the above-mentioned configuration, and when performing excavation work using the hydraulic excavator 1, the operator gets into the cab 5 and operates a travel lever / pedal device (not shown) to drive the hydraulic excavator 1 to a desired work site. The operator then operates a work lever device (not shown) to rotate the boom 8, arm 9, and bucket 10 of the work device 7 while rotating the upper rotating body 3, thereby performing excavation work of earth and sand. When performing various works including this excavation work, the operator can easily and accurately perform the work according to the design data by using machine guidance linked to, for example, a global navigation satellite system, a total station, or the like, and performing the work according to the instructions displayed on the monitor 6.

[0042] Here, the excavation claws 12 (points 12B) provided on the bucket 10 may wear or become damaged due to impacts and friction during excavation, resulting in a shortened overall length. Furthermore, when replacing the points 12B of the excavation claws 12, the overall length of the excavation claws 12 changes whether a new point 12B is attached or a used point 12B is attached. If the overall length of the excavation claws 12 changes in this way, it is considered that the work accuracy will decrease when working along machine guidance.

[0043] In contrast, the hydraulic excavator of the invention in Patent Document 1 rotates the bucket while positioning the tip of the digging claw on the ground, detects the movement dimension of any coordinate, and calculates the amount of wear (length dimension) of the digging claw.

[0044] However, because the change in coordinates due to the wear of the excavation claws is small, it is necessary to rotate the bucket so that the position of the tip of the excavation claw does not shift. This requires a solid ground against which the excavation claws can be pressed, and also requires skilled operation techniques for the work device. This makes it difficult to grasp the exact wear of the excavation claws, and reduces the reliability of work using machine guidance. Therefore, in this embodiment, when the hydraulic excavator 1 is operated using the machine guidance, the dimensional display (work instructions) of the machine guidance is corrected by the controller 19.

[0045] Next, the control processing of the controller 19 when working with the hydraulic excavator 1 using the machine guidance and the correction processing of the dimensional display used for the machine guidance will be described with reference to FIG.

[0046] In step S1 of Fig. 8, the excavation claw 12 of the working device 7 is placed at a specific position. Specifically, as shown in Figs. 1 and 2, the arm cylinder 15 and the bucket cylinder 16 are greatly extended to fold the arm 9 and the bucket 10, and the arm 9 and the bucket 10 are placed in a specific position, i.e., at a specific position, using the position detection sensors 17B and 17C so that the excavation claw 12 located at the other end side of the bucket 10 faces the underside 8A of the boom 8. As a result, the other end side of the bucket 10 including the excavation claw 12 is placed at a specific distance and angle with respect to the camera body 18D of the camera 18.

[0047] In this case, the predetermined distance is a distance that allows two or more excavation claws 12 to be photographed when the camera 18 photographs the other end side of the bucket 10. In this embodiment, as shown in Fig. 7, the distance is set to a distance that allows five excavation claws 12 to be photographed.

[0048] The predetermined angular position is an angle at which the base end 12A1 of the adapter 12A and the tip end 12B1 of the point 12B can be clearly photographed, and is preferably an angular position at which the optical axis of the camera body 18D is perpendicular or approximately perpendicular to the cutting edge 11E. This allows the camera 18 to clearly photograph the entirety of the multiple excavation claws 12 from the front of the excavation claws 12.

[0049] Next, once the digging claws 12 of the working device 7 have been placed in a specific position, the process proceeds to step S2, in which multiple (five) digging claws 12 (on the other end side of the bucket 10) are photographed with the camera 18, and in step S3, the photographed image data is transmitted to the controller 19.

[0050] In step S4, the image data is subjected to image analysis to extract the individual excavation claws 12. For example, the controller 19 analyzes the image captured by the camera 18 to clarify the outer edges (contours) of the five excavation claws 12, thereby extracting overall images of the five excavation claws 12 from the image data.

[0051] In the next step S5, the controller 19 counts the number of pixels used in the linear distance from the base end 12A1 of the adapter 12A to the tip end 12B1 of the point 12B for the five excavation claws 12. Then, the calculated length dimension L1 of each excavation claw 12 is calculated from the relationship between the pixel interval dimension (number of pixels) of the camera body 18D and the number of counted pixels. Here, if there is variation in the calculated length dimensions L1 of the five excavation claws 12, the average value L0 of each calculated length dimension L1 is used.

[0052] After the calculated length dimension L0 of the excavation claw 12 is calculated, the process proceeds to step S6, where the amount of change between the reference length dimension (reference value) L2 of the excavation claw 12 to which the unworn (new) point 12B that has been stored in advance is attached and the calculated length dimension L0 of the excavation claw 12 is reflected in the toe position calculation to calculate the difference dimension ΔL. In the following step S7, a correction is performed by adding the calculated difference length dimension ΔL to the numerical value used for the machine guidance. That is, the instruction is given so that the bucket 10 can be moved closer to the excavation surface by the amount of wear (length dimension ΔL) of the excavation claw 12. In step S8, the corrected toe position information (correction value) is displayed on the monitor 6. Then, the operator can perform the work accurately by referring to the toe position information displayed on the monitor 6.

[0053] Thus, the hydraulic excavator 1 according to this embodiment is equipped with a camera that photographs the bucket 10 of the working implement 7, and the controller 19 analyzes the image of the bucket 10 taken by the camera 18 to calculate the length dimension L1 (L0) of the excavation claw 12, and reflects the calculated amount of change in the length dimension L1 (L0) of the excavation claw 12 in the tip position calculation.

[0054] Therefore, the calculated length dimension L1 (L0) of the excavation claw 12 can be easily and accurately measured without requiring skilled operation techniques for the working device 7. As a result, it is possible to improve the reliability when performing work using machine guidance or machine control with the hydraulic excavator 1.

[0055] Furthermore, the camera 18 is rotatably attached to the underside 8A of the boom 8. As a result, even if the arm 9 or the bucket 10 is replaced, the camera 18 (camera body 18D) can be made to face the other end side of the bucket 10. Furthermore, the shooting range of the camera 18 is also adjustable.

[0056] Further, the bucket 10 has a plurality of excavation claws 12, for example, five, arranged in the left-right direction, and the camera 18 is configured to photograph an area including two or more of the five excavation claws 12 (five in this embodiment) out of the five excavation claws 12. This allows the calculated length dimension L1 of the multiple excavation claws 12 to be obtained as the average length dimension L0, thereby improving the reliability (accuracy) of the correction of the machine guidance.

[0057] Furthermore, the device is provided with a monitor 6 as a display device. The controller 19 corrects a reference value based on the length dimension L1 (L0) of the excavation claw 12 calculated by analyzing the image of the excavation claw 12 captured by the camera 18, and performs a toe position calculation based on the corrected reference value, while displaying information on the tip 12B1 of the point 12B, which is the calculated toe position of the excavation claw 12, on the monitor 6. This allows the user to easily perform accurate work by visually checking the monitor 6 and following the machine guidance.

[0058] Next, Fig. 9 and Fig. 10 show a second embodiment of the present invention. The feature of this embodiment is that the controller controls the working device so that the tip position of the digging claw moves along a pre-specified path based on the attitude of the working device detected by the attitude detection sensor and the tip position of the digging claw calculated by the tip position calculation. Hereinafter, such a control method of the digging claw is referred to as "machine control". In the second embodiment, the same components as those in the first embodiment described above are given the same reference numerals, and their description will be omitted.

[0059] The traveling operation device 21 is configured to include a traveling lever / pedal device located in the cab 5 and provided in front of the driver's seat, and a traveling control valve (neither shown) that operates the drive wheels (travel motor) of the lower traveling body 2 in response to operation of the traveling lever / pedal device. The work operation device 22 is configured to include work lever devices located in the cab 5 and provided on both the left and right sides of the driver's seat, and a work control valve (neither shown) that operates the work device 7 and the swing device in response to operation of the work lever devices. The traveling operation device 21 and the work operation device 22 are connected to an output section of a controller 23.

[0060] Like the controller 19 of the first embodiment, the controller 23 of the second embodiment has a memory unit 23A that stores processing programs such as image analysis and calculation of the calculated length dimension L1 of the excavation claw 12, as well as the reference length dimension L2 of the excavation claw 12 when a new point 12B is attached. The controller 23 of the second embodiment differs from the controller 19 of the first embodiment in that it has a work control unit 23B and a function for correcting the numerical values ​​of the machine control. When performing machine control, the controller 23 of the second embodiment corrects the numerical values ​​by reflecting changes in the overall length dimension of the excavation claw 12 due to wear, damage, etc.

[0061] The work control unit 23B controls the work device 7 so that the tip 12B1 of the excavation claw 12 operates along a pre-specified route, based on the attitude of the work device 7 detected by the attitude detection sensors 17A, 17B, 17C and the tip 12B1 of the excavation claw 12 calculated by a toe position calculation. The work control unit 23B also compares the coordinates of the design data input in advance with the current coordinates calculated using a global navigation satellite system, a total station, etc., and restricts the movement of the work device 7 so as not to dig too much when, for example, the work device 7 is operated to excavate more than the design data.

[0062] Next, the control processing of the controller 23 and the numerical correction of the machine control when working with the hydraulic excavator 1 using the machine control will be described with reference to FIG.

[0063] Steps S11 to S16 in FIG. 10 are the same as steps S1 to S6 in the first embodiment. In step S18, a correction is performed by adding the length dimension ΔL corresponding to the calculated difference to the numerical value used for machine control. That is, the operation limit is changed so that the bucket 10 can be moved closer to the excavation surface by the amount of wear (length dimension ΔL) of the excavation claw 12. In step S19, the machine control is performed using the corrected numerical value (correction value). Specifically, the controller 23 takes into account the difference dimension ΔL between the reference length dimension L2 of the excavation claw 12 stored in the memory unit 23A and the calculated length dimension L1, and moves the excavation claw 12 (bucket 10) along a specified path by machine control by the work control unit 23B, so that accurate work can be easily performed.

[0064] Thus, the second embodiment configured as above can also provide the same effects and advantages as the first embodiment. In particular, according to the second embodiment, the working device 7 includes the attitude detection sensors 17A, 17B, and 17C for identifying the attitude of the working device 7, and the controller 23 includes a memory unit 23A for storing the reference length dimension L2 of the excavation claw 12, and a work control unit 23B for moving the excavation claw 12 along a path designated in advance based on the reference length dimension L2 of a new excavation claw 12 and information from the attitude detection sensors 17A, 17B, and 17C, and the controller 23 can move the excavation claw 12 along a designated path by machine control of the work control unit 23B, taking into account the difference ΔL between the reference length dimension L2 of the excavation claw 12 stored in the memory unit 23A and the calculated length dimension L1. This allows accurate work to be easily performed even if the calculated length dimension L1 changes due to wear of the excavation claw 12.

[0065] Next, Fig. 11 and Fig. 12 show a third embodiment of the present invention. The feature of this embodiment is that the controller is provided with a work control unit that moves the digging claw along a pre-specified path based on the calculated length dimension of the digging claw and information from the attitude detection sensor. In the third embodiment, the same components as those in the second embodiment described above are given the same reference numerals, and their description will be omitted.

[0066] 11, the controller 31 of the third embodiment has, in the same manner as the controller 23 of the second embodiment, a processing program for image analysis, calculation of the calculated length dimension L1 of the excavation claw 12, etc., stored in a memory unit 23A. However, the controller 31 of the third embodiment differs from the controller 23 of the second embodiment in that it has a function of updating the numerical values ​​of the machine control instead of correcting the numerical values ​​of the machine control. The numerical value update of the machine control updates the numerical values ​​when performing the machine control, reflecting dimensional changes of the excavation claw 12 due to wear, damage, etc.

[0067] The work control unit 31B moves the excavation claw 12 (bucket 10) along a pre-specified route based on the calculated length dimension L1 of the excavation claw 12 and information from the attitude detection sensors 17A, 17B, 17C. The work control unit 31B compares the coordinates of the design data input in advance with the current coordinates calculated using a global navigation satellite system, a total station, etc., and performs machine control to restrict the movement of the work device 7 so that it does not dig too much, for example, when the work device 7 is operated to excavate more than the design data.

[0068] Next, the control processing of the controller 31 and updating of the numerical values ​​of the machine control when the hydraulic excavator 1 is operated using the machine control will be described with reference to FIG.

[0069] Steps S21 to S25 in FIG. 12 are the same as steps S11 to S15 in the second embodiment. In step S26, the numerical value used for the machine control is updated according to the calculated length dimension L1 of the excavation claw 12. That is, in the third embodiment, the length of the excavation claw 12 is not treated as a fixed value, but is updated each time to the length measured in the immediately preceding step S25. In step S27, the machine control is executed using the updated numerical value. Specifically, the controller 31 moves the excavation claw 12 (bucket 10) along a specified path by the machine control by the work control unit 31B based on the calculated length dimension L1 of the excavation claw 12 and information from the attitude detection sensors 17A, 17B, and 17C, so that accurate work can be easily performed. The update frequency of the length of the excavation claw 12 can be set arbitrarily, and it is possible to set it to update only when the engine is started and not update during a series of work, or to update every time a certain number of excavation work is performed.

[0070] According to the third embodiment, the working device 7 includes attitude detection sensors 17A, 17B, and 17C for identifying the attitude of the working device 7, and the controller 31 includes a work control unit 31B for moving the excavation claw 12 along a pre-specified path based on the calculated length dimension L1 of the excavation claw 12 and information from the attitude detection sensors 17A, 17B, and 17C. The claw tip is controlled based on the length of the excavation claw 12 measured each time machine control is performed, so that the claw tip is always accurately controlled. In addition, in the third embodiment, even if the excavation claw 12 is replaced with another excavation claw (such as a flat claw) and the length changes, the numerical value used for machine control is updated according to the calculated length dimension of the excavation claw calculated each time, so that it can be easily handled.

[0071] In the embodiment, an example is shown in which all of the five excavation claws 12 are photographed by the camera 18. However, the present invention is not limited to this, and for example, one to four excavation claws 12 may be photographed. Also, one to four or six or more excavation claws may be provided on the bucket.

[0072] Also, in the embodiment, the excavation claw 12 is formed of two members, an adapter 12A fixed to the bucket body 11, and a point 12B detachably attached to the adapter 12A. However, the present invention is not limited to this, and for example, the excavation claw may be configured to be detachably attached to the bucket body using a bolt.

[0073] Furthermore, in the embodiment, the hydraulic excavator 1 equipped with a crawler-type lower traveling body 2 has been described as an example. However, the present invention is not limited to this, and may be applied to a hydraulic excavator equipped with a wheel-type lower traveling body. The display device in the present invention is not limited to the monitor described above, and may be any medium capable of displaying various information, and may be, for example, a head-mounted display or an aerial display. [Explanation of symbols]

[0074] 1. Hydraulic excavator 2 Undercarriage (car body) 3 Upper rotating body (car body) 6 Monitor (display device) 7 Working Equipment 8. Boom 8A Bottom 10 Buckets 12 Digging Claw 12B points 12B1 Tip (tip position) 18 Camera 19,23,31 Controller 19A,23A,31A Storage section 23B, 31B Work control section L1(L0) Calculated length of the excavation jaw L2 Reference length dimension of excavation jaws (reference value)

Claims

1. The car body and a working device provided on the vehicle body and having a bucket at its tip; an attitude detection sensor that detects the attitude of the working device; a controller that executes a tip position calculation to calculate a tip position of the excavation claws of the bucket based on the attitude of the work device detected by the attitude detection sensor; In a construction machine equipped with A camera is provided to photograph the bucket, The controller analyzes the image of the bucket taken by the camera to calculate the length dimension of the digging claw, and reflects the calculated change in the length dimension of the digging claw in the toe position calculation.

2. The construction machine according to claim 1, The working device includes a boom having one end rotatably attached to the vehicle body, and an arm having one end rotatably attached to the other end of the boom, The bucket has one end rotatably attached to the other end of the arm, and the excavation claw protrudes from the other end. The construction machine is characterized in that the camera is rotatably attached to the underside of the boom.

3. The construction machine according to claim 1, The excavation claws are provided in plurality and aligned in the left-right direction of the bucket, The construction machine is characterized in that the camera photographs an area including two or more of the plurality of digging claws.

4. The construction machine according to claim 1, Further comprising a display device, The controller stores a reference value of the length dimension of the digging claw, The controller corrects the reference value based on the length dimension of the digging claw calculated by analyzing the image of the digging claw taken by the camera, calculates the toe position using the corrected reference value, and displays the calculated information on the toe position of the digging claw on the display device.

5. The construction machine according to claim 1, The controller controls the working device so that the tip position of the digging claw moves along a pre-specified path based on the attitude of the working device detected by the attitude detection sensor and the tip position of the digging claw calculated by the toe position calculation.

Images