Work machine

Abstract

To provide a work machine capable of loading a fixed point of a loading target with a load.SOLUTION: A work machine includes a controller that drives a boom, an arm 32, and a bucket 33 at a target loading point P set above a load-carrying tray 56 to make operation of discharging sediment held by the bucket 33 be performed automatically. The controller drives the boom, the arm 32, and the bucket 33 so that after the bucket 33 is turned so that an opening surface of the bucket 33 is vertical at the target loading point P, the opening surface of the bucket 33 faces downward while a position T in a longitudinal direction of a tip of the bucket 33, a position with respect to a machine body, is maintained.SELECTED DRAWING: Figure 5C

Description

Technical Field

[0001] The present invention relates to a working machine that automatically performs an operation of discharging a load held by a bucket.

Background Art

[0002] Patent Document 1 discloses a system that automatically controls a hydraulic excavator to perform earth discharging with respect to a transport vehicle stopped at a loading position. In Patent Document 1, the position of the loading platform of the transport vehicle is detected from an image captured by a camera, and automatic earth discharging is executed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, when discharging a load (such as earth and sand), if only the bucket is rotated, there will be variations in the position where the load is loaded onto the loading target (such as the loading platform of the transport vehicle). For example, depending on the quality of the earth and sand, the earth and sand may be discharged at the initial stage of rotation or at the later stage of rotation, resulting in variations in the loading position of the earth and sand. Therefore, it is desired that the load can be loaded at a fixed point of the loading target.

[0005] An object of the present invention is to provide a working machine capable of loading a load at a fixed point of a loading target.

Means for Solving the Problems

[0006] The present invention includes a machine body, a boom rotatably attached to the machine body in the vertical direction, an arm rotatably attached to the boom in the vertical direction, a bucket rotatably attached to the arm in the front-rear direction, and a controller that automatically performs an operation of discharging a transported object held by the bucket by driving the boom, the arm, and the bucket at a target loading point set above the loading target. The controller rotates the bucket so that the opening surface of the bucket is vertical at the target loading point, and then drives the boom, the arm, and the bucket so that the opening surface of the bucket faces downward while maintaining the position in the front-rear direction of the tip of the bucket with respect to the machine body.

Effects of the Invention

[0007] According to the present invention, after the bucket is rotated so that the opening surface of the bucket is vertical at the target loading point, the boom, the arm, and the bucket are driven so that the opening surface of the bucket faces downward while maintaining the position in the front-rear direction of the tip of the bucket with respect to the machine body. By making the opening surface of the bucket face downward while maintaining the position of the tip of the bucket with respect to the machine body, it is possible to make the position where the transported object is discharged substantially the same from the initial stage to the later stage of the rotation of the bucket. Thereby, the transported object can be loaded at a fixed point of the loading target.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5A

Figure 5B

Figure 5C

Figure 5D

Mode for Carrying Out the Invention

[0009] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0010] (Configuration of the Working Machine) The working machine according to the embodiment of the present invention automatically performs an operation of discharging a load held by the bucket. As shown in FIG. 1 which is a side view of the working machine 1, the working machine 1 is a machine that performs work with the attachment 30, for example, a hydraulic excavator. The working machine 1 has a machine body 24 including a lower traveling body 21 and an upper revolving body 22, an attachment 30, and a cylinder 40.

[0011] The lower traveling body 21 is a part for traveling the working machine 1 and includes, for example, crawlers. The upper revolving body 22 is rotatably attached to the upper part of the lower traveling body 21 via a slewing device 25. A cab (driver's cab) 23 is provided at the front of the upper revolving body 22.

[0012] The attachment 30 is attached to the upper swing body 22 so as to be rotatable in the vertical direction. The attachment 30 includes a boom 31, an arm 32, and a bucket 33. The boom 31 is attached to the upper swing body 22 so as to be rotatable (liftable) in the vertical direction. The arm 32 is attached to the boom 31 so as to be rotatable in the vertical direction. The bucket 33 is attached to the arm 32 so as to be rotatable in the front-rear direction. The bucket 33 is a part for performing operations such as excavation, leveling, and scooping of earth and sand (the object to be transported). Note that the object to be transported is not limited to earth and sand, and may be stones or waste (such as industrial waste).

[0013] The cylinder 40 can rotate the attachment 30 hydraulically. The cylinder 40 is a hydraulic telescopic cylinder. The cylinder 40 includes a boom cylinder 41, an arm cylinder 42, and a bucket cylinder 43.

[0014] The boom cylinder 41 rotates the boom 31 with respect to the upper swing body 22. The base end portion of the boom cylinder 41 is rotatably attached to the upper swing body 22. The tip end portion of the boom cylinder 41 is rotatably attached to the boom 31.

[0015] The arm cylinder 42 rotates the arm 32 with respect to the boom 31. The base end portion of the arm cylinder 42 is rotatably attached to the boom 31. The tip end portion of the arm cylinder 42 is rotatably attached to the arm 32.

[0016] The bucket cylinder 43 rotates the bucket 33 with respect to the arm 32. The base end portion of the bucket cylinder 43 is rotatably attached to the arm 32. The tip end portion of the bucket cylinder 43 is rotatably attached to a link member 34 that is rotatably attached to the bucket 33.

[0017] Further, the working machine 1 has an angle sensor 52 and an inclination angle sensor 60.

[0018] The angle sensor 52 detects the turning angle of the upper slewing body 22 with respect to the lower traveling body 21. The angle sensor 52 is, for example, an encoder, a resolver, or a gyro sensor. In the present embodiment, the turning angle of the upper slewing body 22 when the front of the upper slewing body 22 coincides with the front of the lower traveling body 21 is set to 0°.

[0019] The inclination angle sensor 60 detects the attitude of the attachment 30. The inclination angle sensor 60 includes a boom inclination angle sensor 61, an arm inclination angle sensor 62, and a bucket inclination angle sensor 63.

[0020] The boom inclination angle sensor 61 is attached to the boom 31 and detects the attitude of the boom 31. The boom inclination angle sensor 61 is a sensor that acquires the inclination angle of the boom 31 with respect to the horizontal line, and is, for example, an inclination (acceleration) sensor or the like. Note that the boom inclination angle sensor 61 may be a rotation angle sensor that detects the rotation angle of the boom foot pin (base end of the boom) or a stroke sensor that detects the stroke amount of the boom cylinder 41.

[0021] The arm inclination angle sensor 62 is attached to the arm 32 and detects the attitude of the arm 32. The arm inclination angle sensor 62 is a sensor that acquires the inclination angle of the arm 32 with respect to the horizontal line, and is, for example, an inclination (acceleration) sensor or the like. Note that the arm inclination angle sensor 62 may be a rotation angle sensor that detects the rotation angle of the arm connection pin (base end of the arm) or a stroke sensor that detects the stroke amount of the arm cylinder 42.

[0022] The bucket inclination angle sensor 63 is attached to the link member 34 and detects the attitude of the bucket 33. The bucket inclination angle sensor 63 is a sensor that acquires the inclination angle of the bucket 33 with respect to the horizontal line, and is, for example, an inclination (acceleration) sensor or the like. Note that the bucket inclination angle sensor 63 may be a rotation angle sensor that detects the rotation angle of the bucket connection pin (base end of the bucket) or a stroke sensor that detects the stroke amount of the bucket cylinder 43.

[0023] (Configuration of the transport vehicle) As shown in FIG. 2 which is a side view of the transporter 3, the transporter 3 is a vehicle having a loading platform 56 to be loaded. The transporter 3 is a vehicle for transporting earth and sand (loaded goods) loaded by the working machine 1, and may be a dump truck or a truck.

[0024] The transporter 3 includes a main body 55 and a loading platform 56. The main body 55 is capable of traveling and supports the loading platform 56. The main body 55 includes a driver's cab 57. The loading platform 56 is arranged on the rear side of the transporter 3 with respect to the driver's cab 57.

[0025] Hereinafter, regarding the direction related to the transporter 3, the side from the driver's cab 57 toward the loading platform 56 is referred to as the "rear side of the transporter", and the side from the loading platform 56 toward the driver's cab 57 is referred to as the "front side of the transporter".

[0026] The loading platform 56 does not have a lid and is, for example, box-shaped. The loading platform 56 includes a floor surface 56a, a rear tilting plate surface 56b, side tilting plate surfaces 56c, and a torii surface 56d. The floor surface 56a is the bottom surface (lower surface) of the loading platform 56. The rear tilting plate surface 56b is the rear side surface of the loading platform 56 and protrudes upward from the rear side portion of the floor surface 56a. The side tilting plate surfaces 56c are the left and right surfaces of the loading platform 56 and protrude upward from the left and right ends of the floor surface 56a. The torii surface 56d is the front side surface of the loading platform 56 and protrudes upward from the front side portion of the floor surface 56a. The torii surface 56d protrudes higher than the side tilting plate surfaces 56c and higher than the rear tilting plate surface 56b.

[0027] The loading platform 56 accommodates earth and sand (loaded goods). The loading platform 56 may be movable with respect to the main body 55 or may be fixed to the main body 55. Note that the object to be loaded (dump operation) by the working machine 1 may not be the loading platform 56 of the transporter 3, and may be, for example, a container directly placed on the ground or the like.

[0028] (Configuration of the mobile terminal) As shown in Fig. 1, the mobile terminal 5 is a terminal operated by an operator at the work site, for example, a tablet terminal. The mobile terminal 5 can communicate with the working machine 1. Note that the mobile terminal 5 may be a smartphone or the like.

[0029] (Circuit configurations of the working machine and the mobile terminal) As shown in Fig. 3, which is a circuit diagram of the working machine 1 and the mobile terminal 5, the working machine 1 includes a controller 11, a working machine side communication device 12, and a storage device 13.

[0030] The controller 11 automatically controls the working machine 1. The controller 11 causes the working machine 1 to automatically perform a series of operations from earthwork excavation to soil discharge. That is, the working machine 1 is automatically operated. Specifically, the controller 11 automatically operates the slewing device 25 and the attachment 30 based on the detection values of the angle sensor 52 and the tilt angle sensor 60.

[0031] The working machine side communication device 12 can communicate with the mobile terminal side communication device 16 of the mobile terminal 5 to be described later. The storage device 13 can store the target loading point to be described later.

[0032] The mobile terminal 5 includes a mobile terminal side controller 15, a mobile terminal side communication device 16, a display 17, and a touch panel 18.

[0033] The mobile terminal side communication device 16 can communicate with the working machine side communication device 12 of the working machine 1. The mobile terminal side controller 15 receives information on the position of the tip of the arm 32 (the base end of the bucket 33) from the working machine 1 via the mobile terminal side communication device 16.

[0034] Here, as shown in FIG. 4 which is a top view of the work machine 1 and the transport vehicle 3, a series of operations from earth and sand excavation to soil discharge are performed with the transport vehicle 3 stopped such that the longitudinal direction of the transport vehicle 3 is along the turning direction of the upper swing body 22 of the work machine 1. That is, after scooping up earth and sand with the bucket 33 from the earth and sand accumulation 70, the upper swing body 22 is turned to position the bucket 33 above the loading platform 56 of the transport vehicle 3. Then, after discharging the soil into the loading platform 56, the upper swing body 22 is turned in the direction opposite to that just before to position the bucket 33 above the earth and sand accumulation 70. This is automatically repeated. The earth and sand accumulation 70 is an earth and sand pit or an earth and sand hill.

[0035] The controller 11 of the work machine 1 sets a target loading point P above the loading platform 56. The target loading point P is a target position at which the work machine 1 performs a loading operation (soil discharge operation) on the transport vehicle 3. The loading operation is an operation of discharging the earth and sand held by the bucket 33 onto the loading platform 56. The setting of the target loading point P is performed by so-called teaching.

[0036] Teaching is performed as follows. First, by manual operation by the operator, the tip of the arm 32 (the base end of the bucket 33) is positioned above the loading platform 56. The operator holding the portable terminal 5 confirms this position, and if there is no problem, operates the touch panel 18 to determine the position. This information is transmitted to the controller 11 of the work machine 1, and the position of the tip of the arm 32 at this time is set as the target loading point P and stored in the storage device 13.

[0037] By teaching, a plurality of target loading points P are set in the longitudinal direction of the loading platform 56. The target loading point P is set at the center of the width of the loading platform 56 in the direction (lateral direction) orthogonal to the longitudinal direction and the vertical direction of the loading platform 56, respectively.

[0038] The controller 11 causes the loading operation to be performed with respect to the target loading point P set by itself. At this time, the controller 11 rotates the bucket 33 so that the opening surface of the bucket 33 is vertical at the target loading point P, and then drives the boom 31, the arm 32, and the bucket 33 so that the opening surface of the bucket 33 faces downward while maintaining the position of the tip of the bucket 33 in the front-rear direction with respect to the machine body 24.

[0039] Specifically, as shown in FIGS. 5A to 5D which are side views of the arm 32 and the bucket 33, the boom 31, the arm 32, and the bucket 33 are driven. First, as shown in FIG. 5A, with the earth and sand held by the bucket 33, the tip of the arm 32 is positioned at the target loading point P, and there, the boom 31, the arm 32, and the bucket 33 are stopped. At this time, the opening surface of the bucket 33 is horizontal.

[0040] Next, as shown in FIG. 5B, the bucket 33 is rotated so that the opening surface of the bucket 33 becomes vertical. As a result, a part of the earth and sand held by the bucket 33 falls onto the loading platform 56.

[0041] Next, as shown in FIG. 5C, while maintaining the position T in the front-rear direction of the tip of the bucket 33 with respect to the machine body 24, the boom 31, the arm 32, and the bucket 33 are driven so that the opening surface of the bucket 33 faces downward. Specifically, the boom 31 is rotated so that the opening surface of the bucket 33 faces downward, and the arm 32 is moved (pulled) toward the upper slewing body 22. As the boom 31 rotates, the earth and sand in the bucket 33 falls onto the loading platform 56.

[0042] Then, as shown in FIG. 5D, the opening surface of the bucket 33 is directed downward. As a result, almost all of the earth and sand held by the bucket 33 falls onto the loading platform 56.

[0043] While maintaining the position T of the tip of the bucket 33 with respect to the machine body 24, by turning the opening surface of the bucket 33 downward, it is possible to make the position where the earth and sand are discharged substantially the same from the initial stage to the later stage of the rotation of the bucket 33. As a result, the earth and sand can be loaded at a fixed point on the loading platform 56.

[0044] Also, by causing the operation of discharging the earth and sand at the target loading point P set at the central portion of the loading platform 56 in the short side direction of the loading platform 56, it is possible to suppress the earth and sand from spilling from the loading platform 56.

[0045] Note that it is conceivable to drive the boom 31, the arm 32, and the bucket 33 so as to maintain the position T of the tip of the bucket 33 from the state where the opening surface of the bucket 33 is horizontal (the state shown in FIG. 5A) to the state where the opening surface of the bucket 33 faces downward (the state shown in FIG. 5D). However, in this case, since the tip of the bucket 33 is closer to the upper swing body 22 than the tip of the arm 32, when the bucket 33 is rotated, the bucket 33 may protrude from the loading platform 56 on the upper swing body 22 side, and there is a risk that the earth and sand will spill outside the loading platform 56. Therefore, it is conceivable to position the tip of the bucket 33 at the target loading point P so that the bucket 33 does not protrude from the loading platform 56. However, in this case, the tip of the arm 32 may be too far from the upper swing body 22, and there is a risk that the opening surface of the bucket 33 cannot be kept horizontal due to the structure of the attachment 30.

[0046] In the present embodiment, with the opening surface of the bucket 33 being horizontal, the tip of the arm 32 is positioned at the target loading point P. After the opening surface of the bucket 33 is made vertical, the bucket 33 is rotated while maintaining the position T of the tip of the bucket 33 with respect to the machine body 24, so that the opening surface of the bucket 33 can be kept horizontal or the bucket 33 can be prevented from protruding from the loading platform 56.

[0047] (Effect) As described above, according to the working machine 1 according to the present embodiment, at the target loading point P, after the bucket 33 is rotated so that the opening surface of the bucket 33 becomes vertical, the boom 31, the arm 32, and the bucket 33 are driven so that the opening surface of the bucket 33 faces downward while maintaining the position of the tip of the bucket 33 in the front-rear direction T with respect to the machine body 24. By making the opening surface of the bucket 33 face downward while maintaining the position of the tip of the bucket 33 with respect to the machine body 24, it is possible to make the positions where the earth and sand are discharged substantially the same from the initial stage to the later stage of the rotation of the bucket 33. As a result, the earth and sand can be loaded at a fixed point on the loading platform 56.

[0048] Further, the target loading point P is set at the center of the loading platform 56 in a direction orthogonal to the longitudinal direction and the vertical direction of the loading platform 56, respectively. By performing the operation of discharging the earth and sand at such a target loading point P, it is possible to suppress the earth and sand from spilling from the loading platform 56.

[0049] The embodiments of the present invention have been described above, but they are merely examples, and do not particularly limit the present invention. The specific configuration and the like can be appropriately changed in design. Further, the actions and effects described in the embodiments of the invention are merely a list of the most suitable actions and effects resulting from the present invention, and the actions and effects according to the present invention are not limited to those described in the embodiments of the present invention.

Explanation of reference numerals

[0050] 1 Working machine 3 Transport vehicle 5 Portable terminal 11 Controller 12 Working machine side communication device 13 Storage device 15 Portable terminal side controller 16 Portable terminal side communication device 17 Display 18 Touch panel 21 Lower traveling body 22 Upper revolving body 23 Cab 24 Machine body 25 Swing device 30 Attachment 31 Boom 32 Arm 33 Bucket 34 Link member 40 Cylinder 41 Boom cylinder 42 Arm cylinder 43 Bucket cylinder 52 Angle sensor 55 Main body part 56 Loading platform (object to be loaded) 57 Driver's cab 60 Tilt angle sensor 61 Boom tilt angle sensor 62 Arm tilt angle sensor 63 Bucket tilt angle sensor

Claims

1. A machine body, a boom rotatably attached to the machine body in the vertical direction, an arm rotatably attached to the boom in the vertical direction, a bucket rotatably attached to the arm in the front-rear direction, a controller that automatically performs an operation of discharging a conveyed object held by the bucket by driving the boom, the arm, and the bucket at a target loading point set above the loading target, and having, after rotating the bucket so that the opening surface of the bucket is vertical at the target loading point, the controller drives the boom, the arm, and the bucket so that the opening surface of the bucket faces downward while maintaining the position in the front-rear direction of the tip of the bucket at the position with respect to the machine body. The working machine is characterized by this.

2. The working machine according to claim 1, wherein the target loading point is set at the center of the loading target in a direction orthogonal to the longitudinal direction and the vertical direction of the loading target, respectively.

Images