Arm-type work machine

Abstract

To provide an arm-type work machine equipped with a hanging attachment, and that can easily and accurately adjust the attitude of the attachment to a desired tilt angle prior to drilling and driving work along the desired tilt angle other than the vertical direction.SOLUTION: An inclination angle α of an auger screw 12 when drilling into the ground is set. A tip position of a second arm 8 at the time when the auger screw 12 is maintained in a vertical posture and its lower end is grounded at a drilling point Pgrd in the ground is calculated as the reference coordinate Pstan. Further, the tip position of the second arm 8 at the time when the auger screw 12 is tilted following a tilt angle α while maintaining the grounding state is calculated as the target coordinate Ptgt. Coordinates P1 to P4 at each predetermined angle are calculated as an arcuate locus when moving from the reference coordinate Pstan to the target coordinate Ptgt. Based on these coordinates Pstan, P1 to P4, Ptgt, the tip of the second arm 8 is moved to adjust the attitude of the auger screw 12 to a predetermined angle.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to an articulated working machine.

Background Art

[0002] In foundation work of buildings, operations such as drilling vertical holes in the ground or driving piles, sheet piles, etc. (hereinafter sometimes referred to as drilling and driving respectively) are performed, and an articulated working machine is known as a working machine for such foundation work. For example, an articulated working machine is provided with an upper revolving body having an articulated working front turnably on a lower traveling body capable of traveling, and a suspended attachment is connected to the tip of the arm of the working front. In the operation of drilling a vertical hole, a hydraulic auger that rotationally drives an auger screw is connected as an attachment, the lower end of the auger screw maintained in a vertical posture by its own weight is grounded on the ground, and it is drilled while being rotationally driven by the hydraulic auger and pushed into the ground. Further, in the driving operation, a vibro hammer that grips and vibrates a pile or a sheet pile is connected as an attachment, the lower end of the pile or the sheet pile maintained in a vertical posture by its own weight is grounded on the ground, and it is vibrated by the vibro hammer and driven into the ground.

[0003] The direction of drilling and driving in the ground, that is, the drilling direction by the auger screw or the driving direction of the pile or the sheet pile is not limited to the vertical direction, and if the inclination angle of the attachment is changed back and forth, drilling and driving can be performed at any inclination angle other than the vertical direction. At any inclination angle including the vertical direction, if the inclination angle of the attachment changes during the drilling and driving operation, it will cause factors such as a decrease in construction accuracy or damage to the auger screw, pile, and sheet pile. Therefore, it is necessary to keep the attachment at the intended inclination angle from the start to the end of the drilling and driving operation. For this purpose, the operator of the working machine is required to perform a complicated operation of moving the tip of the arm of the working front linearly along the inclination angle while operating at least two arms constituting the working front.

[0004] To reduce the burden on operators, for example, Patent Document 1 discloses an arm-type work machine that automatically moves the Augus screw along the vertical direction (inclination angle = 0°). In this technology, the coordinates of the tip position of the second arm along the vertical direction, which gradually changes as the Augus screw drills, are calculated sequentially based on the length and angle of the first and second arms at the work front, and the coordinates where the tip of the first arm should be positioned at this time are also calculated sequentially. Then, by controlling the trajectory of the first and second arms based on these coordinates, the tip of the second arm, and consequently the Augus screw, is moved along the vertical direction to drill into the ground.

[0005] Furthermore, Patent Document 2 discloses an arm-type work machine capable of drilling into the ground at any angle of inclination, not limited to the vertical direction. In this technology, the coordinates of the tip positions of the first and second arms are corrected based on the set inclination angle of the Auguscru, and the trajectory of the first and second arms is controlled based on the corrected coordinates, thereby moving the Auguscru along the inclination angle to drill into the ground. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Special Publication No. 4-54792 [Patent Document 2] Special Publication No. 7-76453 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] For example, in the technology described in Patent Document 2, when drilling into the ground at a predetermined angle of inclination using an Auguscrew, the Auguscrew's posture is adjusted prior to the drilling operation. In the case of a suspended attachment, the posture adjustment is performed by placing the lower end of the Auguscrew on a predetermined drilling point on the ground, and while maintaining this contact state, displacing the upper end of the Auguscrew, in other words, the tip of the second arm, forward or backward.

[0008] As a result, the tip of the second arm moves forward or backward from a vertical position, following an arc-shaped trajectory centered on the drilling point. Therefore, the operator manipulates the work front so that the tip of the second arm moves along this trajectory. If it deviates from the trajectory during movement, the lower end of the Auguscru will either separate from the ground or dig into the ground, and in either case, it will be impossible to adjust the attachment to the desired inclination angle, making the manipulation of the work front highly difficult.

[0009] Furthermore, because the operator on board the work machine has difficulty recognizing the tilt angle of the augerscrew in the front-to-back direction, an assistant worker standing near the drilling site visually checks the movement trajectory of the tip of the second arm and the tilt of the augerscrew, and signals the operator to move the arm. Therefore, the operator needs to check the signals from the assistant worker while operating the work front. Because such a difficult and complicated task is required of the operator, it takes time to start the actual drilling work, which reduces work efficiency. In addition, because the tilt angle cannot be accurately adjusted by visual inspection, it is difficult to obtain good construction accuracy.

[0010] On the other hand, in addition to adjusting the posture of the August Cru by operator manipulation, methods using jigs are also employed. For example, the jig is triangular in shape with a hypotenuse corresponding to the length of the August Cru, and the angle of the hypotenuse relative to the base that touches the ground is set to be equal to the inclination angle of the August Cru. The jig is placed adjacent to the drilling site on the ground, and the lower end of the August Cru is brought into contact with the drilling site and then tilted towards the jig. The August Cru then leans against the hypotenuse of the jig and maintains a posture along the hypotenuse, i.e., the desired inclination angle.

[0011] However, the jigs are quite heavy and bulky, and on the other hand, at the construction site, it is necessary to transport the jig to the next drilling site after each drilling completion, which requires a great deal of effort. Also, foundation work requires various inclination angles for attachments, and since a jig must be prepared for each, there was room for improvement in terms of construction costs.

[0012] The present invention was made to solve these problems, and its objective is to provide an arm-type work machine equipped with a suspended attachment that can easily and accurately adjust the orientation of the attachment to a desired inclination angle without using jigs or the like for holding the attachment's orientation, prior to drilling and driving operations along a desired inclination angle other than the vertical direction. [Means for solving the problem]

[0013] To achieve the above objective, the present invention provides an arm-type work machine comprising a multi-joint work front consisting of at least a first arm at the base end and a second arm at the tip end, each driven by an actuator, a controller for controlling the drive of each actuator, and an attachment for drilling and driving into the ground suspended from the tip of the second arm, wherein the arm-type work machine has an inclination angle setting device for setting the inclination angle of the attachment when drilling and driving into the ground, the controller comprises a drilling and driving control unit that drives the actuators of the first and second arms respectively and moves the tip of the second arm along the inclination angle to drill and drive into the ground in the attachment, and a device that adjusts the posture of the attachment to the inclination angle prior to drilling and driving into the ground by the drilling and driving control unit The posture adjustment control unit comprises: a reference coordinate calculation unit that calculates the tip position of the second arm as a reference coordinate when the attachment is kept in a vertical position and its lower end is in contact with the drilling / driving point in the ground; a target coordinate calculation unit that calculates the tip position of the second arm as a target coordinate when the attachment is tilted according to the tilt angle while maintaining contact with the drilling / driving point; a trajectory estimation unit that estimates an arc-shaped trajectory centered on the drilling / driving point when the tip of the second arm moves from the reference coordinate to the target coordinate; and a tilt execution unit that drives the actuators of the first and second arms, respectively, and moves the tip of the second arm from the reference coordinate to the target coordinate by following the arc-shaped trajectory estimated by the trajectory estimation unit. [Effects of the Invention]

[0014] According to the arm-type work machine of the present invention, equipped with a suspended attachment, the attachment can be easily and accurately adjusted to a desired inclination angle prior to drilling or driving work along a desired inclination angle other than the vertical direction, without the need to use jigs or the like for holding the attachment's posture. [Brief explanation of the drawing]

[0015] [Figure 1]It is a side view showing the articulated working machine of the embodiment. [Figure 2] It is a control block diagram showing the controller of the articulated working machine. [Figure 3] It is a flowchart showing the attitude adjustment routine executed by the controller. [Figure 4] It is an explanatory diagram showing the state where the auger screw is tilted to the tilt angle on flat ground. [Figure 5] It is an explanatory diagram showing the state where the lower end of the auger screw is grounded at the drilling point on a sloping ground. [Figure 6] It is an explanatory diagram showing the state where the auger screw is tilted to the tilt angle on a sloping ground. [Figure 7] It is an explanatory diagram showing the state where the auger screw is tilted to the tilt angle on a sloping ground in another example.

Mode for Carrying Out the Invention

[0016] Hereinafter, an embodiment of the articulated working machine embodying the present invention will be described. FIG. 1 is a side view showing the articulated working machine of the present embodiment. In the following description, the vertical, front-rear, and left-right directions are defined mainly based on the operator on the working machine.

[0017] A pair of left and right crawlers 3 are provided on the lower traveling body 2 of the articulated working machine 1 (hereinafter simply referred to as the working machine). The crawlers 3 are driven by a traveling hydraulic motor (not shown) to make the working machine 1 travel. An upper revolving body 4 is provided on the lower traveling body 2, and the upper revolving body 4 is driven by a revolving hydraulic motor (not shown) to revolve. A cab 5 is provided on the front left side of the upper revolving body  4, and a working front 6 is provided on the front right side.

[0018] The work front 6 consists of the first and second arms 7 and 8. The base end of the first arm 7 is connected to the upper revolving body 4 via a pin 4a so as to be rotatable along the vertical and longitudinal and lateral directions. Also, the base end of the second arm 8 is connected to the tip of the first arm 7 via a pin 7a so as to be rotatable along the vertical and longitudinal and lateral directions. The first arm 7 is rotated by a hydraulic first cylinder 9 (actuator), and accordingly, the tip of the first arm 7 is displaced in position. The second arm 8 is rotated by a hydraulic second cylinder 10 (actuator), and accordingly, the tip of the second arm 8 is displaced in position.

[0019] A machine room 11 is provided at the rear side of the cab 5, and a hydraulic power unit (not shown), which is the power source of the working machine 1, is housed therein. Although details will not be described, the hydraulic power unit functions to drive a hydraulic pump by an engine and switch the discharged hydraulic oil by a switching valve according to the operation of the operator. In accordance with this switching, the hydraulic oil is supplied to the traveling and slewing hydraulic motors, the first and second cylinders 9 and 10, etc. described above, and also supplied to a hydraulic auger 13 and a vibro hammer described below, whereby the working machine 1 operates.

[0020] An attachment corresponding to the construction content of the foundation work is connected to the tip of the second arm 8. For example, when drilling a vertical hole in the ground, as shown in FIG. 1, a hydraulic auger 13 that rotationally drives an auger screw 12 is connected as an attachment, and a pile is inserted into the vertical hole drilled by the auger screw 12 to serve as a foundation. Also, although not shown, when driving a pile, a sheet pile, etc. into the ground, a vibro hammer that grips and vibrates the pile and the sheet pile is connected as an attachment, and the pile and the sheet pile driven into the ground thereby serve as a foundation. Also, there are cases where the hydraulic auger 13 is used when driving a steel pipe into the ground. Spiral fins are welded in advance to the lower end portion of the steel pipe, and the upper end thereof is connected to the hydraulic auger 13 instead of the auger screw 12 and rotationally driven to be driven into the ground.

[0021] In this embodiment, the attachment of the work machine 1 is of the suspension type, so that the upper end of the attachment is connected to the tip of the second arm 8 via a pin 8a so that it can swing in the front-rear direction, and the attachment is maintained in a vertical position by its own weight. In addition to this suspension type attachment, there are also attachments that can adjust the tilt angle via a link mechanism using a hydraulic cylinder (hereinafter referred to as cylinder-driven type), but the suspension type has the following advantages.

[0022] (a) Many foundation construction projects require vertical drilling and concrete pouring, but cylinder-driven attachments require angle adjustment in all cases, regardless of the inclination angle. In contrast, suspended attachments maintain a vertical position automatically, eliminating the need for angle adjustment.

[0023] (b) Depending on the specifications of the work front 6, there is an upper limit to the total weight of attachments that can be supported. With cylinder-driven attachments, the weight, length, and size of the Augus screws 12, piles, sheet piles, etc., which are directly involved in drilling and driving operations, are limited by the amount of equipment such as hydraulic cylinders and linkage mechanisms. Such limitations can reduce work efficiency, but with suspended attachments, the limitations on these components are relaxed, thus improving work efficiency.

[0024] (c) In foundation work, attachments may need to be changed depending on the construction details at the drilling and pouring points, so quick attachment and detachment of attachments is required. In cylinder-driven systems, where the attachment is connected to the work front via a link mechanism and hydraulic cylinder, it is time-consuming because all of these connection points must be separated. In contrast, with the suspension type, attachments can be attached and detached simply by inserting and removing a single pin 8a that connects the work front 6 and the attachment, thus providing excellent ease of attachment and detachment and contributing to improved work efficiency.

[0025] While suspended attachments have the advantages mentioned above, they present the aforementioned problems when adjusting the attachment to an inclination angle other than vertical prior to drilling and casting work. Specifically, adjusting the attachment's orientation by operating the operator's work front 6 requires a highly difficult and complicated operation, and it is not possible to accurately adjust the inclination angle. Furthermore, when adjusting the attachment's orientation using a jig, it is necessary to transport the jig to each drilling and casting location, and a jig corresponding to the attachment's inclination angle must be prepared.

[0026] In light of these problems, the inventor focused on the automated drilling and casting technologies described in Patent Documents 1 and 2. These technologies use trajectory control of the first and second arms 7 and 8 to automatically drill and cast the attachment along the vertical direction and other inclination angles (hereinafter referred to as the desired inclination angle including the vertical direction). This trajectory control can also be applied to adjusting the posture when tilting the attachment to the desired inclination angle.

[0027] In other words, since the suspended attachment has the characteristic of being naturally maintained in a vertical position by its own weight, the vertical position can be used as a reference when adjusting the attachment's position. Therefore, the tip position of the second arm 8 (i.e., the position of pin 8a) when the lower end of the attachment is in contact with the drilling / casting point can be defined as the reference coordinate Pstan, and the tip position of the second arm 8 when the attachment is tilted to the desired inclination angle from this state can be identified as the target coordinate Ptgt. As a result, the trajectory from the reference coordinate Pstan to the target coordinate Ptgt, more specifically, the arc-shaped trajectory centered on the drilling / casting point as the tip of the second arm 8 moves from the reference coordinate Pstan to the target coordinate Ptgt can be determined, and trajectory control can be performed to drive the work front 6 to follow this trajectory.

[0028] Based on the above findings, this embodiment automates the adjustment of the attachment's posture, which was previously operated manually by an operator. The following describes the case where a hydraulic auger 13 that rotates the auger screw 12 is connected as an attachment. Figure 2 is a control block diagram showing the controller for the arm-type work machine 1.

[0029] The controller 15 consists of a drilling control unit 16 for drilling holes in the ground and a posture adjustment control unit 17 for adjusting the posture of the Auguscru 12. The drilling control unit 16 performs the function of drilling into the ground by moving the Augus screw 12 along a predetermined inclination angle α including the vertical direction, and corresponds to the "drilling and driving control unit" of the present invention. For example, if a vibro-hammer for driving piles or sheet piles is used as an attachment, the configuration corresponding to the "drilling and driving control unit" will be referred to as the driving control unit.

[0030] The input side of the drilling control unit 16 is connected to a first arm angle sensor 18 that detects the angle of the first arm 7 relative to the upper rotating body 4, a second arm angle sensor 19 that detects the angle of the second arm 8 relative to the first arm 7, an operating lever 20 and a display 21 for the work front 6 located in the operator's cab 5. The operating lever 20 is a device for operating the work front 6, and according to the direction and amount of operation of the lever, the first and second cylinders 9 and 10 drive each arm 7 and 8 in the corresponding direction and speed.

[0031] The touch panel display 21 shows a message display unit 21a that displays operating instructions to the operator, a numeric keypad 21b (inclination angle setting device) for entering various setting values, and a completion button 21c for indicating completion of an operation. Following the display on the message display unit 21a, the operator operates the work machine 1 for drilling the ground, and simultaneously operates the numeric keypad 21b and the completion button 21c as appropriate.

[0032] Furthermore, the first and second cylinders 9 and 10 are connected to the output side of the drilling control unit 16 via a hydraulic circuit 22. The hydraulic circuit 22 consists of a pair of electromagnetic proportional valves (not shown) connected to the first and second cylinders 9 and 10, respectively. Drive signals from the drilling control unit 16 switch each of the electromagnetic proportional valves in the hydraulic circuit 22, and accordingly, hydraulic fluid from the hydraulic pump 23 is supplied to the first and second cylinders 9 and 10, respectively, and each cylinder 9 and 10 is driven individually in any direction and at any speed.

[0033] The control details of the drilling control unit 16 are similar to those described in Patent Documents 1 and 2, for example, so only a brief overview is provided here. For details, please refer to the respective publications. The drilling operation is started with the lower end of the Augus screw 12 in a vertical position with the ground contact point Pgrd, or with the lower end in contact with the ground but tilted to a predetermined inclination angle α. In the case of the vertical position, the Augus screw 12 is drilled along the vertical direction. In the case of other inclination angles α, the tip of the second arm 8 needs to be moved along the vertical direction or the predetermined inclination angle α to drill the Augus screw 12 along that predetermined inclination angle α.

[0034] Therefore, the drilling control unit 16 controls the trajectory of the first and second arms 7 and 8 based on the predetermined lengths of the first and second arms 7 and 8 (the distance between the axes of both ends of each arm 7 and 8), and the angles of each arm 7 and 8 detected by the first and second arm angle sensors 18 and 19. That is, as drilling is performed by the Augus screw 12, the coordinates of the tip of the second arm 8 along the inclination angle α gradually change. For this reason, the coordinates of the tip of the second arm 8 are calculated sequentially based on the above information on arm length and arm angle, and the coordinates where the tip of the first arm 7 should be positioned are also calculated sequentially. Then, based on each coordinate, a drive signal is output to the hydraulic circuit 22 to drive the first and second cylinders 9 and 10, thereby controlling the angles of the first and second arms 7 and 8 to move the tip of the second arm 8, in other words the Augus screw 12, along the predetermined inclination angle α including the vertical direction, while drilling into the ground.

[0035] The attitude adjustment control unit 17 performs the function of adjusting the attitude of the Auguscru 12 to a predetermined inclination angle α prior to drilling into the ground, and consists of a reference coordinate calculation unit 17a, a target coordinate calculation unit 17b, a trajectory estimation unit 17c, and an inclination execution unit 17d.

[0036] The input side of the reference coordinate calculation unit 17a is connected to the first arm angle sensor 18, the second arm angle sensor 19, and the display 21, while the output side is connected to the target coordinate calculation unit 17b and the tilt execution unit 17d. The reference coordinate calculation unit 17a calculates the tip position of the second arm 8 as the reference coordinate Pstan on a coordinate system with the front-to-back direction as the X-axis and the up-to-down direction as the Y-axis, based on the angles of the first and second arms 7 and 8 when the lower end of the Auguscrew 12 is in contact with the drilling point Pgrd, and outputs this to the target coordinate calculation unit 17b and the trajectory estimation unit 17c, respectively. The origin of the coordinate system (0,0) may be set to any position; for example, a predetermined position on the work machine 1 may be set as the origin, or the reference coordinate Pstan may be set as the origin.

[0037] The input side of the target coordinate calculation unit 17b is connected to the reference coordinate calculation unit 17a and the display 21, and the output side is connected to the trajectory estimation unit 17c. Based on the predetermined length of the Augustus screw 12 (distance from pin 8a to the lower end), the reference coordinate Pstan input from the reference coordinate calculation unit 17a, and the inclination angle α input via the numeric keypad 21b of the display 21, the target coordinate calculation unit 17b calculates the coordinates of the tip position of the second arm 8 (i.e., the position of pin 8a) when the Augustus screw 12 is tilted according to the inclination angle α, and this is called the target coordinate Ptgt. In this embodiment, the inclination angle α is input and set with respect to the vertical direction.

[0038] The input side of the trajectory estimation unit 17c is connected to the reference coordinate calculation unit 17a and the target coordinate calculation unit 17b, and the output side is connected to the inclination execution unit 17d. The trajectory estimation unit 17c estimates the arc-shaped trajectory when the tip of the second arm 8 is moved from the reference coordinate Pstan to the target coordinate Ptgt while the lower end of the Auguscrew 12 is in contact with the drilling point Pgrd.

[0039] In this embodiment, the coordinates of the tip position of the second arm 8 (exemplified as Pstan, P1~P4, Ptgt in Figure 4) are sequentially calculated at predetermined angles (for example, every 5°) centered on the drilling point Pgrd, from the reference coordinate Pstan to the target coordinate Ptgt, and these coordinates are considered as the arc-shaped trajectory of the movement of the tip of the second arm 8. Furthermore, the coordinates where the tip of the first arm 7 (i.e., pin 7a) should be located when the tip of the second arm 8 is located at each of the calculated coordinates Pstan, P1~P4, Ptgt (exemplified as Pstan', P1'~P4', Ptgt' in Figure 4) are also sequentially calculated and output to the tilt execution unit 17d at predetermined angles, linked to the coordinates of the tip position of the second arm 8.

[0040] As described below, the first and second arms 7 and 8 are controlled by these coordinates to adjust the attitude of the Auguscru 12. In this embodiment, instead of a continuous trajectory, coordinates are calculated at predetermined angles that are set in advance to a degree that does not hinder attitude adjustment. This has the advantage of reducing the computational load on the controller 15 compared to cases where a continuous trajectory is calculated.

[0041] The input side of the tilt execution unit 17d is connected to the trajectory estimation unit 17c and the operating lever 20, while the output side is connected to the hydraulic circuit 22 and the display 21. Based on coordinates at predetermined angles input from the trajectory estimation unit 17c, the tilt execution unit 17d drives the first and second cylinders 9 and 10, respectively, to rotate the first and second arms 7 and 8. Specifically, the coordinates relating to the tip positions of the first and second arms 7 and 8 are read sequentially from the reference coordinate Pstan side, and based on the operating direction and stroke amount of each cylinder 9 and 10 to move the tip of each arm 7 and 8 to the corresponding coordinate, a drive signal for the electromagnetic proportional valve is created and output to the hydraulic circuit 22. As a result, the tip of the second arm 8 is intermittently moved at predetermined angles along an arc-shaped trajectory, while the attitude of the Auguscru 12 is adjusted to the tilt angle α.

[0042] Next, we will explain the attitude adjustment control performed by the controller 15 when adjusting the attitude of the August Cru 12, specifically the case when drilling work is performed on flat ground, i.e., ground perpendicular to the vertical direction (inclination angle β=0°). Figure 3 is a flowchart showing the posture adjustment routine executed by the controller 15. The controller 15 executes this routine at a predetermined control interval when a posture adjustment button (not shown) is operated by the operator.

[0043] First, in step S1, the alignment instruction for the August Cru 12 is displayed on the message display section 21a of the display 21. In the following step S2, it is determined whether or not the complete button 21c has been operated, and if it is No (negative), the process returns to step S1. The content of the display in step S1 may be, for example, "After placing the lower end of the August Cru on the drilling site, please operate the complete button." Based on this display, the operator operates the work front 6 using the operating lever 20 to bring the lower end of the augerscrew 12 into contact with the drilling point Pgrd. In the posture adjustment described below, the vertical augerscrew 12 is tilted to an inclination angle α, and in the subsequent ground drilling operation, the augerscrew 12 is moved along the inclination angle α to drill into the ground. These series of operations are performed by moving the tip of the second arm 8 without changing the position of the work machine 1. For this reason, as shown by the dashed line in Figure 4, the position of the work machine 1 relative to the drilling point Pgrd is adjusted so that the tip of the second arm 8 can move within the required area during the operation, and then the augerscrew 12 is aligned with the drilling point Pgrd.

[0044] After alignment is complete, when the operator operates the complete button 21c on the display 21, step S2 determines Yes (affirmative) and proceeds to step S3. In step S3, the angles of each arm 7, 8 detected by the first and second arm angle sensors 18, 19 are read, and in step S4, the coordinates of the tip position of the second arm 8 are calculated as the reference coordinate Pstan based on the angles of each arm 7, 8 (processed by the reference coordinate calculation unit 17a). In the following step S5, an instruction to input the tilt angle α of the August Cru 12 is displayed on the message display unit 21a of the display 21, and in the following step S6, it is determined whether or not the complete button 21c has been operated, and if No, the process returns to step S5. The display content in step S5 may be, for example, "Please operate the complete button after inputting the tilt angle of the August Cru."

[0045] Based on this display, when the operator inputs a tilt angle α relative to the vertical direction using the numeric keypad 21b on the display 21 and operates the complete button 21c, a Yes determination is made in step S6 and the process proceeds to step S7. In step S7, based on the length of the August Cru 12, the reference coordinate Pstan calculated in step S4, and the input tilt angle α, the coordinates of the tip position of the second arm 8 when the August Cru 12 is tilted to the tilt angle α are calculated as the target coordinate Ptgt, as shown by the solid line in Figure 4 (processing by the target coordinate calculation unit 17b).

[0046] In the subsequent step S8, based on the reference coordinate Pstan and target coordinate Ptgt, the coordinates of the tip position of the second arm 8 at predetermined angle intervals from the reference coordinate Pstan to the target coordinate Ptgt are sequentially calculated and stored, as shown in Figure 4, and the coordinates where the tip of the first arm 7 should be located at each of these coordinates are also sequentially calculated and stored (processing by the trajectory estimation unit 17c). As a result, the coordinates of the tip positions of the first and second arms 7 and 8 on the trajectory from the reference coordinate Pstan to the target coordinate Ptgt are stored at predetermined angle intervals.

[0047] Subsequently, in step S9, a message indicating that posture adjustment is ready is displayed on the message display unit 21a of the display 21, and in the following step S10, the operating state of the operating lever 20 is determined. For the determination in step S10, a specific operation of the operating lever 20 is set in advance; for example, the operation of the operating lever 20 when tilting the first arm 7 forward (backward) is set as the specific operation. In this case, the display content in step S9 is, for example, "Posture adjustment is ready. Operating the operating lever in the direction of tilting the first arm forward will start posture adjustment."

[0048] In step S10, if it is determined that the specific operation of the operating lever 20 has not yet been performed, the process of step S10 is repeated while waiting for the operator to operate the lever. Then, if it is determined in step S10 that the operating lever 20 has been operated, the process moves to step S11, where a message such as "Currently adjusting posture." is displayed on the message display unit 21a of the display 21. In the following step S12, the first and second cylinders 9 and 10 are driven to tilt the Auguscru 12 toward the target coordinate Ptgt (processing by the tilt execution unit 17d). Specifically, the coordinates of the tip positions of the first and second arms 7 and 8 are read sequentially from the reference coordinate Pstan side and the first and second cylinders 9 and 10 are driven, and the driving speed and, consequently, the tilt speed of the Auguscru 12 are controlled in accordance with the current amount of operation of the operating lever 20. Therefore, the Auguscru 12 tilts slowly when the amount of operation is small, and tilts more rapidly as the amount of operation increases.

[0049] In the following step S13, it is determined whether the tip of the second arm 8 has reached the target coordinate Ptgt. If the determination is No, the process returns to step S10 and steps S10 to S13 are repeated. Then, as shown by the solid line in Figure 4, when the tip of the second arm 8 reaches the target coordinate Ptgt, a determination of Yes is made in step S13, and in step S14, the completion of posture adjustment is displayed on the message display unit 21a of the display 21, after which the routine ends. The content of the display in step S14 is, for example, "Position adjustment is complete, please proceed to the ground drilling work."

[0050] On the other hand, if it is determined in step S10 that the lever operation has been interrupted while the posture of the August Cru 12 is being adjusted based on the operation of the control lever 20, then in step S15, the interruption of the posture adjustment is displayed on the message display section 21a of the display 21, and then the process returns to step S10. In this case, the process in step S12 is not performed, and the tilt of the August Cru 12 is interrupted at the moment the lever operation is stopped.

[0051] In this case, the display in step S15 might be something like, "Position adjustment has been interrupted. To resume, please operate the control lever again." Then, when the operator resumes operating the lever, the process moves from step S10 to step S12 to resume posture adjustment, and the August Cru 12 begins to tilt again.

[0052] The above explanation applies to flat ground with a slope angle β = 0°, but even on sloped ground, i.e., ground with a slope angle β as shown in Figure 5, the attitude adjustment of the August Cru 12 is performed by the above control. Since the slope angle α input on the display 21 based on the display in step S5 is based on the vertical direction, as shown in Figure 6, regardless of the slope angle β of the ground, an appropriate target coordinate Ptgt is calculated in step S7 based on the slope angle α, and the attitude of the August Cru 12 can be adjusted to the desired slope angle α. Of course, the attitude adjustment can be performed in the same way regardless of the direction in which the ground is sloped, not just the slope directions shown in Figures 5 and 6.

[0053] With the control of the controller 15 described above, the operator can simply place the lower end of the August screw 12 on the drilling point Pgrd, input the desired inclination angle α, and perform a specific operation on the operating lever 20. This allows the posture of the August screw 12 to be automatically adjusted to the inclination angle α by controlling the trajectories of the first and second arms 7 and 8. Therefore, the operator is no longer required to perform the highly difficult operation of moving the tip of the second arm 8 along an arc-shaped trajectory centered on the drilling point Pgrd, as in the past, and there is no need to confirm signals from an assistant. As a result, the posture of the August screw 12 can be adjusted very easily.

[0054] Furthermore, because the posture of the Auguscrew 12 is adjusted by controlling the trajectories of the first and second arms 7 and 8 in this manner, the inclination angle α can be adjusted more accurately compared to when it is based on visual inspection by an assistant worker. Therefore, better construction accuracy can be achieved compared to conventional methods. Furthermore, since no jig is used to hold the Auguscru 12 at the inclination angle α, the need to transport jigs to each drilling point Pgrd is eliminated, reducing labor. Also, since it is not necessary to prepare a jig for each different inclination angle α, construction costs can be reduced.

[0055] On the other hand, in this embodiment, trajectory control of the first and second arms 7 and 8 is performed on the condition that the operating lever 20 is being operated. Therefore, for example, if a worker working nearby comes into contact with the August Cru 12 while its posture is being adjusted, the posture adjustment of the August Cru 12 can be quickly interrupted and dealt with simply by stopping the operation of the operating lever 20.

[0056] In this embodiment, the tilting speed of the August Cru 12 is controlled in accordance with the amount of operation of the operating lever 20. Therefore, when there are many workers around the August Cru 12, for example, the operator can set the amount of operation of the operating lever 20 to small to tilt the August Cru 12 slowly, thereby preparing for unforeseen circumstances such as workers coming into contact with the August Cru 12. Conversely, when there are no workers around, the operator can set the amount of operation of the operating lever 20 to large to tilt the August Cru 12 rapidly, thereby improving work efficiency.

[0057] By the way, in this embodiment, the inclination angle α of the Auguscru 12 was set with respect to the vertical direction, but this is not the only way. For example, the inclination angle α may be set as the angle relative to the ground with respect to the ground, and this case will be explained below as an alternative example.

[0058] (Another example) The configuration of this alternative example of the arm-type work machine 1 is basically the same as that of the embodiment. The differences are that a ground angle sensor 31 (ground angle detection unit) for detecting the ground inclination angle β has been added, as shown by the dashed line in Figure 2, and the content of the calculation process for the target coordinates Ptgt in step S7 in Figure 3 is different. Therefore, the same component numbers are used to indicate parts that are common to both and their descriptions are omitted, while the differences are described in detail.

[0059] The ground angle sensor 31 is connected to the input side of the target coordinate calculation unit 17b and detects the inclination angle β of the ground in the front-rear direction of the work machine 1, in other words, the inclination angle β of the ground along the inclination direction of the August Cru 12. Therefore, if the ground is inclined in a direction different from the inclination direction of the August Cru 12, the component of the ground inclination angle that is along the inclination direction of the August Cru 12 is detected by the ground angle sensor 31 as the inclination angle β.

[0060] When the controller 15 moves from step S6 to step S7 in Figure 3 based on the operation of the completion button 21c, it calculates the coordinates of the tip position of the second arm 8 when the Auguscru 12 is tilted to an inclination angle α as the target coordinate Ptgt (processing by the target coordinate calculation unit 17b). In this alternative example, in addition to the length of the Auguscru 12, the reference coordinate Pstan, and the inclination angle α, the inclination angle β of the ground detected by the ground angle sensor 31 is also applied to the calculation process.

[0061] Figure 7 shows the case where the ground slopes downwards in the direction of the Augustus Cru 12's inclination (to the left in the figure). Therefore, the tip position of the second arm 8 is calculated as the target coordinate Ptgt when the vertically positioned Augustus Cru 12 is tilted by an angle obtained by adding the inclination angle α to the ground inclination angle β (α+β). If the ground slopes in the opposite direction, the tip position of the second arm 8 is calculated as the target coordinate Ptgt when the vertically positioned Augustus Cru 12 is tilted by an angle obtained by subtracting the ground inclination angle β from the inclination angle α (α-β). Note that on flat ground, an inclination angle β=0 is detected, so the target coordinate Ptgt is calculated based on the inclination angle α, as in the embodiment.

[0062] Therefore, in this alternative example as well, regardless of the ground inclination angle β, the target coordinate Ptgt corresponding to the inclination angle α of the August Cru 12 can be calculated, thereby allowing the attitude of the August Cru 12 to be adjusted to the desired inclination angle α.

[0063] This concludes the description of the embodiments, but the aspects of the present invention are not limited to these embodiments. For example, in the above embodiments and other examples, the arm-type work machine 1 is embodied as an attachment in which a hydraulic auger 13 that rotates the auger screw 12 is connected to the work front 6, but it is not limited to this. For example, a vibro-hammer that grips and vibrates piles or sheet piles may be connected to the work front 6 as an attachment, or a steel pipe with fins welded to its lower end may be connected to the hydraulic auger 13 instead of the auger screw 12. In these cases as well, the same effects and advantages as described above can be achieved.

[0064] Furthermore, in the above embodiment and other examples, the trajectory control of the first and second arms 7 and 8 is performed on the condition that the operating lever 20 is operated, and the tilt speed of the August Cru 12 is controlled in accordance with the amount of operation of the operating lever 20, but this is not limited to this. For example, the trajectory control of the first and second arms 7 and 8 may be performed to the end when a dedicated button is operated once, and the tilt speed of the August Cru 12 may be kept constant at this time. [Explanation of symbols]

[0065] 1. Arm-type work machine 6. Front of work 7. First Arm 8. Second Arm 9. First cylinder (actuator) 10. Second cylinder (actuator) 12 August Cru (Attachment) 13. Hydraulic Auger (Attachment) 15 Controllers 16. Drilling Control Unit (Drilling and Casting Control Unit) 17 Posture Adjustment Control Unit 17a Reference Coordinate Calculation Unit 17b Target coordinate calculation section 17c Trajectory estimation part 17d Inclination execution unit 20 Operating levers 21 displays 21b Numeric keypad (tilt angle setting device) 31. Ground Angle Sensor (Ground Angle Detection Unit)

Claims

1. An arm-type work machine comprising a multi-joint work front consisting of at least a first arm at the base end and a second arm at the tip end, each driven by an actuator, having a controller for controlling the drive of each actuator, and having an attachment for drilling and driving into the ground suspended from the tip of the second arm, It has a tilt angle setting device for setting the tilt angle of the attachment when drilling and driving into the ground, The aforementioned controller, A drilling and driving control unit drives the actuators of the first and second arms respectively, and moves the tip of the second arm along the inclination angle to drill and drive holes in the ground into the attachment, Prior to drilling and driving the ground by the drilling and driving control unit, the attitude adjustment control unit adjusts the attitude of the attachment to the inclination angle, Equipped with, The attitude adjustment control unit is A reference coordinate calculation unit calculates the tip position of the second arm as a reference coordinate when the attachment is kept in a vertical position and its lower end is in contact with the drilling / driving point in the ground, A target coordinate calculation unit calculates the tip position of the second arm as the target coordinate when the attachment is tilted according to the tilt angle while maintaining contact with the drilling and driving point, A trajectory estimation unit estimates the arc-shaped trajectory centered on the drilling / driving point when the tip of the second arm moves from the reference coordinate to the target coordinate, A tilt execution unit drives the actuators of the first and second arms respectively and moves the tip of the second arm from the reference coordinates to the target coordinates by following the arc-shaped trajectory estimated by the trajectory estimation unit, An arm-type work machine characterized by having the following features.

2. The trajectory estimation unit calculates the coordinates of the tip of the second arm at predetermined angles centered on the drilling / casting point as the arc-shaped trajectory. The tilt execution unit drives the actuators of the first and second arms, respectively, based on the coordinates calculated by the trajectory estimation unit. The arm-type work machine according to feature 1.

3. The trajectory estimation unit calculates the coordinates of the tip of the second arm at predetermined angles centered on the drilling / casting point as the arc-shaped trajectory, and calculates the coordinates where the tip of the first arm should be located when the tip of the second arm is located at each of the calculated coordinates. The tilt execution unit drives the actuators of the first and second arms, respectively, based on the coordinates of the first and second arms calculated by the trajectory estimation unit. The arm-type work machine according to feature 1.

4. The tilt angle setting device sets the tilt angle of the attachment with respect to the vertical direction, The target coordinate calculation unit calculates the target coordinates based on the predetermined length of the attachment, the reference coordinates calculated by the reference coordinate calculation unit, and the inclination angle set by the inclination angle setting device. An arm-type work machine according to any one of claims 1 to 3.

5. The system further includes a ground angle detection unit for detecting the inclination angle of the ground, The tilt angle setting device sets the tilt angle of the attachment as the angle relative to the ground with respect to the ground, The target coordinate calculation unit calculates the target coordinates based on the predetermined length of the attachment, the reference coordinates calculated by the reference coordinate calculation unit, the inclination angle set by the inclination angle setting device, and the inclination angle of the ground detected by the ground angle detection unit. An arm-type work machine according to any one of claims 1 to 3.

6. The first and second arms are driven by the actuators according to the direction and amount of operation of the operating levers by the operator, respectively. The tilting mechanism moves the tip of the second arm on the condition that the operating lever is operated in a predetermined direction. An arm-type work machine according to any one of claims 1 to 3.

7. The tilting mechanism moves the tip of the second arm at a speed corresponding to the amount of the operating lever is moved. The arm-type work machine according to feature 6.

8. The aforementioned attachment is a hydraulic auger that rotates the auger screw to drill into the ground. The arm-type work machine according to feature 1.

9. The aforementioned attachment is a vibro-hammer that grips piles or sheet piles and drives them into the ground while vibrating them. The arm-type work machine according to feature 1.

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