JP7876397B2 - Arm-type work machine - Google Patents

Description

This invention relates to an arm-type work machine.

In building foundation work, tasks such as drilling vertical holes in the ground or driving piles or sheet piles into the ground (hereinafter sometimes referred to as drilling and driving, respectively) are performed. Arm-type work machines are known as such for foundation work. For example, an arm-type work machine consists of a rotatable upper rotating body with a multi-jointed working front mounted on a movable lower traveling body, with a suspended attachment connected to the tip of the arm of the working front. For vertical hole drilling, a hydraulic auger that rotates the auger screw is connected as an attachment. The lower end of the auger screw, maintained vertically by its own weight, is placed in contact with the ground, and the hydraulic auger rotates it, pushing it into the ground while drilling. For driving, a vibro-hammer that grips and vibrates piles or sheet piles is connected as an attachment. The lower end of the pile or sheet pile, maintained vertically by its own weight, is placed in contact with the ground, and the vibro-hammer vibrates it, driving it into the ground.

The direction of drilling and driving into the ground, i.e., the direction of drilling with the Auguscrew, or the direction of driving piles and sheet piles, is not limited to the vertical direction. By changing the inclination angle of the attachment, drilling and driving can be performed at any inclination angle other than the vertical. Regardless of the inclination angle, including the vertical direction, if the inclination angle of the attachment changes during drilling and driving, it can reduce construction accuracy or damage the Auguscrew, piles, or sheet piles. Therefore, it is necessary to maintain the attachment at the desired inclination angle from the start to the end of the drilling and driving operation. To achieve this, the operator of the work machine is required to perform the complex task of moving the tips of the arms of the work front in a straight line along the inclination angle while operating at least two arms that constitute the work front.

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, based on the lengths and angles of the first and second arms at the work front, the coordinates of the tip position of the second arm along the vertical direction, which gradually changes as the Augus screw drills, are sequentially calculated, and the coordinates where the tip of the first arm should be positioned at this time are also sequentially calculated. 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.

Furthermore, Patent Document 2 discloses an arm-type drilling 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 Augus screw, and the trajectory of the first and second arms is controlled based on the corrected coordinates. This allows the Augus screw to move along the inclination angle and drill into the ground.

Special Publication No. 4-54792 Special Publication No. 7-76453

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 orientation is adjusted prior to the drilling operation. In the case of a suspended attachment, the orientation adjustment is performed by placing the lower end of the Auguscrew on a predetermined drilling point in the ground, and then, while maintaining this contact, shifting the upper end of the Auguscrew—in other words, the tip of the second arm—forward or backward.

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 the trajectory is deviated during movement, the lower end of the Augus screw will either separate from the ground or dig into it, making it impossible to adjust the attachment to the desired inclination angle. Thus, manipulating the work front becomes highly difficult.

Furthermore, because the operator on the work machine has difficulty recognizing the tilt angle of the Augus screw in the front-to-back direction, an assistant worker standing near the drilling point visually confirms the movement trajectory of the tip of the second arm and the tilt of the Augus screw, and signals the operator to control the direction of arm operation. Therefore, the operator needs to confirm signals from the assistant worker while operating the work front. Because such a highly difficult and complicated task is required of the operator, it takes time before the actual drilling work can begin, reducing work efficiency. Moreover, since the tilt angle cannot be accurately adjusted through visual confirmation, it is difficult to achieve good construction accuracy.

On the other hand, in addition to adjusting the orientation of the Augustus crune through 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 Augustus crune, and the angle of the hypotenuse relative to the base that contacts the ground is set to be equal to the inclination angle of the Augustus crune. By placing the jig adjacent to the drilling point on the ground, and then tilting the Augustus crune towards the jig after its lower end has contacted the drilling point, the Augustus crune leans against the hypotenuse of the jig, maintaining an orientation along the hypotenuse, i.e., the desired inclination angle.

However, the jigs are quite heavy and bulky, and on the other hand, at the construction site, they need to be transported to the next drilling site after each drilling completion, which requires a great deal of labor. Furthermore, foundation work requires various attachment angles, and since a separate jig is needed for each, there was room for improvement in terms of construction costs.

This invention was made to solve the aforementioned problems, and its objective is to provide an arm-type work machine equipped with a suspended attachment that allows for easy and accurate adjustment of the attachment's orientation to a desired inclination angle prior to drilling or driving operations along a desired inclination angle other than the vertical, without the need for jigs or other devices to maintain the attachment's orientation.

To achieve the above objective, the arm-type work machine of the present invention comprises a multi-jointed 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, and a controller for controlling the driving of each actuator, and an attachment for drilling and driving into the ground suspended from the tip of the second arm, and comprises an inclination angle setting device for setting the inclination angle of the attachment when drilling and driving into the ground, the controller drives the actuators of the first and second arms respectively, and a drilling and driving control unit moves the tip of the second arm along the inclination angle to drill and drive into the ground in the attachment, and prior to drilling and driving into the ground by the drilling and driving control unit, the device adjusts the posture of the attachment to the inclination angle The device comprises a posture adjustment control unit, the posture adjustment control unit having: a reference coordinate calculation unit that calculates the tip position of the second arm as a reference coordinate when the attachment is maintained 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.

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 the desired inclination angle prior to drilling or driving operations along a desired inclination angle other than the vertical, without the need for jigs or other devices to maintain the attachment's posture.

This is a side view showing an arm-type work machine of an embodiment. This is a control block diagram showing the controller for an arm-type work machine. This is a flowchart showing the posture adjustment routine executed by the controller. This is an explanatory diagram showing the condition of an August Cru vineyard on flat ground, tilted to its desired angle. This is an explanatory diagram showing the lower end of the August Cru in contact with the drilling site on a sloping ground. This is an explanatory diagram showing the state of August Cru on a sloping site, tilted to the specified angle. This is an explanatory diagram showing an example where the August Cru is tilted to a specific angle on a sloping site.

The following describes one embodiment of an arm-type work machine embodying the present invention.
Figure 1 is a side view showing the arm-type work machine of this embodiment, and in the following description, the up/down, front/back, and left/right directions are defined primarily from the perspective of the operator riding on the work machine.

The lower traveling body 2 of the arm-type work machine 1 (hereinafter simply referred to as the work machine) is equipped with a pair of left and right crawlers 3. The crawlers 3 are driven by a hydraulic motor (not shown) to move the work machine 1. An upper slewing body 4 is provided on the lower traveling body 2, and the upper slewing body 4 rotates, driven by a hydraulic motor (not shown) for rotation. A driver's cab 5 is provided on the front left side of the upper slewing body 4, and a work front 6 is provided on the front right side.

The working front 6 consists of first and second arms 7 and 8. The base end of the first arm 7 is rotatably connected to the upper slewing body 4 via a pin 4a, allowing it to move vertically and longitudinally. The base end of the second arm 8 is also rotatably connected to the tip of the first arm 7 via a pin 7a, allowing it to move vertically and longitudinally. The first arm 7 is rotated by a hydraulic first cylinder 9 (actuator), causing its tip to shift position accordingly. The second arm 8 is rotated by a hydraulic second cylinder 10 (actuator), causing its tip to shift position accordingly.

A machine room 11 is located behind the driver's cab 5, and inside is a hydraulic power unit (not shown) that serves as the power source for the work implement 1. While details will not be explained here, the hydraulic power unit drives a hydraulic pump using an engine and switches the discharged hydraulic fluid via a switching valve according to the operator's driving operations. This switching supplies the hydraulic fluid to the aforementioned travel and slewing hydraulic motors, the first and second cylinders 9 and 10, etc., as well as to the hydraulic auger 13 and vibro-hammer described below, thereby operating the work implement 1.

An attachment is connected to the tip of the second arm 8 according to the construction details of the foundation work. For example, when drilling a vertical hole in the ground, as shown in Figure 1, a hydraulic auger 13 that rotates the 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 the foundation. Also, although not shown in the figure, when driving piles or sheet piles into the ground, a vibro-hammer that grips and vibrates the piles or sheet piles is connected as an attachment, so that the piles or sheet piles driven into the ground serve as the foundation. In addition, a hydraulic auger 13 may be used when driving steel pipes into the ground. A spiral fin is welded to the lower end of the steel pipe beforehand, and the upper end is connected to the hydraulic auger 13 in place of the auger screw 12, and the pipe is driven into the ground by rotational drive.

In this embodiment, the attachment of the work machine 1 is of the suspension type. The upper end of the attachment is connected to the tip of the second arm 8 via a pin 8a, allowing it to swing in the front-to-back direction. The attachment is maintained in a vertical position by its own weight. While there are also attachments that allow adjustment of the tilt angle via a link mechanism using a hydraulic cylinder (hereinafter referred to as cylinder-driven attachments), the suspension type has the following advantages.

(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.

(b) The total weight of attachments that can be supported is limited depending on the specifications of the work front 6. In cylinder-driven attachments, the weight, length, and size of the Auger screws 12, piles, sheet piles, etc., directly involved in drilling and driving operations are limited by the hydraulic cylinders, linkage mechanisms, etc. Such limitations reduce work efficiency, but with suspended attachments, these limitations are relaxed, thus improving work efficiency.

(c) In foundation work, attachments may need to be changed depending on the construction details at the drilling and concrete pouring locations, requiring quick attachment and detachment. In cylinder-driven systems, where the attachment is connected to the work front via a link mechanism and hydraulic cylinder, all these connection points must be separated, which is time-consuming. In contrast, with a suspended system, attachment and detachment are possible simply by inserting and removing a single pin 8a connecting the work front 6 and the attachment, resulting in superior attachment and detachment capabilities and improved work efficiency.

While suspended attachments offer the advantages described above, they present the aforementioned problems when adjusting the attachment to an angle other than vertical prior to drilling and concrete placement. Specifically, adjusting the attachment's orientation by operating the operator's work front 6 requires a highly difficult and cumbersome operation, and accurately adjusting the angle of inclination is not possible. Furthermore, adjusting the attachment's orientation using jigs necessitates transporting the jigs to each drilling and concrete placement site, and requires the preparation of jigs corresponding to the attachment's angle of inclination.

In light of these problems, the inventor focused on the automated drilling and casting techniques described in Patent Documents 1 and 2. These techniques involve trajectory control of the first and second arms 7 and 8 to automatically drill and cast along vertical 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 of the attachment when tilting it to the desired inclination angle.

In other words, since the suspended attachment has the characteristic of being naturally maintained in a vertical position due to its own weight, the vertical position can be used as a reference when adjusting the attachment's posture. 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 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.

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, which rotates the auger screw 12, is connected as an attachment.
Figure 2 is a control block diagram showing the controller of the arm-type work machine 1.

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 called the driving control unit.

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, and an operating lever 20 and display 21 of 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, the first and second cylinders 9 and 10 drive each arm 7 and 8 in the corresponding direction and speed.

The touch-panel display 21 shows a message display unit 21a for displaying operation instructions to the operator, a numeric keypad 21b (inclination angle setting device) for inputting 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 needed.

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, driving each cylinder 9 and 10 individually in any direction and at any speed.

The control details of the drilling control unit 16 are similar to those described in, for example, Patent Documents 1 and 2, so only a general overview will be provided; please refer to the respective publications for details. Drilling is initiated with the lower end of the Augus screw 12 in a vertical position, either grounded at the drilling point Pgrd on the ground, or in a position tilted to a predetermined inclination angle α while the lower end remains grounded. In 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 vertically or along the predetermined inclination angle α to drill the Augus screw 12 along that predetermined inclination angle α.

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 occurs with the Augus screw 12, the coordinates of the tip of the second arm 8 along the inclination angle α gradually change. For this reason, based on the information of the arm length and arm angle, the coordinates of the tip of the second arm 8 are calculated sequentially, and the coordinates where the tip of the first arm 7 should be positioned are also calculated sequentially. Then, based on these coordinates, 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.

The attitude adjustment control unit 17 performs the function of adjusting the attitude of the Auguscru 12 to the desired 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.

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 where the front-to-back direction is the X-axis and the up-to-down direction is 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. This calculation unit outputs the Pstan coordinate to the target coordinate calculation unit 17b and the trajectory estimation unit 17c, respectively. The origin of the coordinate system (0,0) can 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.

The input side of the target coordinate calculation unit 17b is connected to the reference coordinate calculation unit 17a and the display 21, while 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 on 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 defined as the target coordinate Ptgt. In this embodiment, the inclination angle α is input and set with respect to the vertical direction.

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, while 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 remains in contact with the drilling point Pgrd.

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 angle intervals (for example, every 5°) centered on the drilling point Pgrd, from the reference coordinate Pstan to the target coordinate Ptgt. 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 positioned 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 angle intervals, linked to the coordinates of the tip position of the second arm 8.

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 finely tuned to the extent that they do not hinder attitude adjustment. Therefore, this offers the advantage of reducing the computational load on the controller 15 compared to cases where a continuous trajectory is calculated.

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. The tilt execution unit 17d rotates the first and second arms 7 and 8 by driving the first and second cylinders 9 and 10, respectively, based on coordinates at predetermined angle intervals input from the trajectory estimation unit 17c. Specifically, the coordinates related to the tip positions of the first and second arms 7 and 8 are read sequentially from the reference coordinate Pstan side. 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. This causes the tip of the second arm 8 to intermittently move along an arc-shaped trajectory at predetermined angle intervals, thereby adjusting the attitude of the Augus screw 12 to the tilt angle α.

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.

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 augerscrew 12, which is in a vertical position, 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.

After alignment is complete, when the operator operates the "Complete" button 21c on the display 21, step S2 determines "Yes" and proceeds to step S3. In step S3, the angles of each arm 7 and 8 detected by the first and second arm angle sensors 18 and 19 are read. 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 and 8 (processed by the reference coordinate calculation unit 17a). In the following step S5, an input instruction for the tilt angle α of the August Cru 12 is displayed on the message display unit 21a of the display 21. In the following step S6, it is determined whether the "Complete" button 21c was operated; if "No," the process returns to step S5. The display content in step S5 might be, for example, "Please operate the 'Complete' button after inputting the tilt angle of the August Cru."

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 Augustus 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 Augustus 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).

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. Simultaneously, 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 along the trajectory from the reference coordinate Pstan to the target coordinate Ptgt are stored at predetermined angle intervals.

Subsequently, in step S9, a message indicating that posture adjustment is ready is displayed on the message display unit 21a of the display 21. 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 pre-set; for example, the operation of the operating lever 20 when tilting the first arm 7 forward (rearward) is set as the specific operation. In this case, the display content in step S9 might be, for example, "Posture adjustment is ready. Operating the operating lever in the direction of tilting the first arm forward will start posture adjustment."

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 proceeds 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 accordingly. The driving speed, and therefore the tilt speed of the Auguscru 12, is controlled according to 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.

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-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 Yes determination 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 ground drilling work."

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

In this case, the display content in step S15 would be, for example, "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.

The above explanation applies to flat ground with a slope angle β = 0°. However, 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 using the above control. Since the slope angle α input to the display 21 based on the display in step S5 is based on the vertical direction, as shown in Figure 6, regardless of the ground's slope angle β, the appropriate target coordinates Ptgt are 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, attitude adjustment can be performed similarly regardless of the direction of the ground's slope, not just the slope directions shown in Figures 5 and 6.

Through the control of the controller 15 described above, the operator simply places the lower end of the August screw 12 on the drilling point Pgrd, inputs the desired tilt angle α, and performs a specific operation on the operating lever 20. The trajectory control of the first and second arms 7 and 8 then automatically adjusts the posture of the August screw 12 to the tilt angle α. 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 conventional systems, and there is no need to confirm signals from an assistant. As a result, the posture of the August screw 12 can be adjusted extremely easily.

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. In addition, since it is not necessary to prepare a jig for each different inclination angle α, construction costs can be reduced.

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 addressed simply by stopping the operation of the operating lever 20.

Furthermore, in this embodiment, the tilting speed of the August Cru 12 is controlled in accordance with the amount of movement of the operating lever 20. Therefore, when, for example, many workers are working around the August Cru 12, the operator can set the amount of movement 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 movement of the operating lever 20 to large to tilt the August Cru 12 rapidly, thereby improving work efficiency.

Incidentally, 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.

《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.

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.

Based on the operation of the completion button 21c, the controller 15 moves from step S6 to step S7 in Figure 3 and calculates the coordinates of the tip position of the second arm 8 when the Auguscru 12 is tilted to the tilt 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 tilt angle α, the tilt angle β of the ground detected by the ground angle sensor 31 is also applied to the calculation process.

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 equal to the sum of the inclination angle α and the ground inclination angle β (α + β). Furthermore, 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 equal to the subtraction of the ground inclination angle β from the inclination angle α (α - β). Note that in 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.

Therefore, even in this alternative example, the target coordinates Ptgt corresponding to the tilt angle α of the Auguscru 12 can be calculated regardless of the ground tilt angle β, thereby allowing the Auguscru 12 to be adjusted to the desired tilt angle α.

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.

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

1. Arm-type work machine 6. Work front 7. First arm 8. Second arm 9. First cylinder (actuator)
10. Second cylinder (actuator)
12. August Cru (Attachment)
13. Hydraulic Auger (Attachment)
15 Controller 16 Drilling control unit (Drilling and casting control unit)
17 Attitude adjustment control unit 17a Reference coordinate calculation unit 17b Target coordinate calculation unit 17c Trajectory estimation unit 17d Tilt execution unit 20 Operating lever 21 Display 21b Keypad (Tilt angle setting device)
31. Ground Angle Sensor (Ground Angle Detection Unit)

Claims (9)

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. 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 arm-type work machine according to claim 1, characterized in that 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 trajectory estimation unit calculates the coordinates of the tip of the second arm at predetermined angles centered on the drilling/driving 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 arm-type work machine according to claim 1, characterized in that 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 tilt angle setting device sets the tilt angle of the attachment with respect to the vertical direction,
The arm-type work machine according to any one of claims 1 to 3, characterized in that the target coordinate calculation unit calculates the target coordinate based on the length of the attachment which is known in advance, the reference coordinate calculated by the reference coordinate calculation unit, and the inclination angle set by the inclination angle setting device. 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 arm-type work machine according to any one of claims 1 to 3, characterized in that the target coordinate calculation unit calculates the target coordinate based on the length of the attachment which is known in advance, the reference coordinate 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. 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,
The inclination execution unit moves the tip of the second arm on the condition that the operating lever is operated in a preset direction, as described in any one of claims 1 to 3. The arm-type work machine according to claim 6, characterized in that the tilting execution unit moves the tip of the second arm at a speed corresponding to the amount of operation of the operating lever. The arm-type work machine according to claim 1, characterized in that the attachment is a hydraulic auger that rotates and drives an auger screw to bore into the ground. The arm-type work machine according to claim 1, characterized in that the attachment is a vibro-hammer that grips a pile or sheet pile and drives it into the ground while vibrating it.