JP2024061463A - crane - Google Patents

Abstract

[Problem] To provide a crane capable of more effectively suppressing swing of a suspended object when the transport operation of the suspended object is stopped. [Solution] The crane has a boom and a suspended object 16 suspended from the boom. If the position where the suspended object 16 is suspended from the boom without swinging is taken as the reference position of the suspended object 16 in a plane coordinate system viewed vertically downward from above the crane, the crane performs a first control to operate the boom 2 to approach the first displaced position 16a1 in the plane coordinate system when the suspended object 16 is at a first displaced position 16a1 displaced from the first reference position, and a second control to operate the boom 2 to approach the second displaced position 16a2 in the plane coordinate system when the suspended object 16 is at a second displaced position 16a2 displaced from a second reference position which is the reference position after the first control. [Selected Figure] Figure 6

Description

The present invention relates to a crane.

Traditionally, cranes have developed technology to transport a suspended object (the hook, the hook, and the load hung on the hook) to a specified location while suppressing the swing of the suspended object (see Patent Document 1).

JP 2004-284735 A

However, there has been a demand for a crane that can more effectively suppress the swinging of a suspended object when the suspended object stops being transported and the object is swinging for some reason (e.g. residual vibrations when the object is stopped, earthquakes, wind, etc.).

The present invention aims to provide a crane that can more effectively suppress the swing of a suspended object when the transport operation of the suspended object is stopped.

The crane according to the present invention has a boom and a suspended object suspended from the boom. The crane according to the present invention is configured to perform a first control to operate the boom to approach the first displaced position in the plane coordinates when the suspended object is in a first displaced position displaced from a first reference position, assuming that the position at which the suspended object is suspended from the boom without swinging is the reference position of the suspended object in a plane coordinates viewed vertically downward from above the crane, and a second control to operate the boom to approach the second displaced position in the plane coordinates when the suspended object is in a second displaced position displaced from a second reference position, which is the reference position after the first control.

The crane of the present invention can more effectively suppress the swing of the suspended object when the transport operation of the suspended object is stopped.

FIG. 1 is a side view of a crane according to an embodiment of the present invention. FIG. 1 is a plan view showing a crane according to an embodiment of the present invention with a portion thereof omitted. FIG. 2 is an enlarged view of a portion of the crane shown in FIG. 1 . FIG. 2 is a block diagram showing a functional configuration of a crane according to the embodiment of the present invention. FIG. 1 is a plan view showing, in a simplified manner, the relationship between the position of a suspended object at maximum amplitude and surrounding structures at a work site. 1A and 1B are diagrams illustrating a first example of a process for preventing a hanging object from swinging. FIG. 7(a) is a plan view showing a second example of a process for preventing the swinging of a suspended object, and FIG. 7(b) is a plan view showing a third example of a process for preventing the swinging of a suspended object. FIG. 11 is a flowchart showing the flow of a process for preventing a hanging object from swinging.

The following describes an embodiment of the present invention in detail with reference to the drawings.

(Crane configuration)
Fig. 1 is a side view of a crane 1 according to this embodiment. Fig. 2 is a plan view of the crane 1 according to the embodiment of the present invention, with parts (boom 2, hoisting rope 3, etc.) omitted. Fig. 3 is a partially enlarged view of the crane 1 shown in Fig. 1, showing the mounting structure of a camera 4.
1 and 2, the crane 1 is a so-called mobile crawler crane. Specifically, the crane 1 includes a self-propelled crawler-type lower traveling body 5 and an upper rotating body 6 rotatably mounted on the lower traveling body 5.
In the following description, the front, rear, left and right directions as seen by a person riding on the crane 1 are defined as the front, rear, left and right directions of the crane 1.

The boom 2 is attached so as to be capable of being raised and lowered to the front side of the upper rotating body 6. A counterweight 7 for balancing the weight of the boom 2 and the suspended load is attached to the rear of the upper rotating body 6.
A cabin 8 in which an operator sits and operates the crane 1 is disposed at the front right side of the upper rotating body 6 .

The boom 2 is raised or lowered by winding or unwinding the hoisting rope 3 using the hoisting winch 10.

One end of the hoisting rope 11 is connected to the hook 12, and the hook 12 is suspended by the hoisting rope 11 wound around a point sheave 17 at the tip of the boom 2. The other end of the hoisting rope 11 is wound around a hoisting winch 13 on the upper rotating body 6, and the hoisting rope 11 is wound up or unwound by driving the hoisting winch 13, thereby raising and lowering the hook 12. A load 14 is suspended from the hook 12 by a string-like, chain-like or other such suspension material 15. In this embodiment, the hook 12 and the load 14 constitute a suspended object 16 suspended from the boom 2.
For ease of explanation, the portion of the hoisting rope 11 that extends away from the point sheave 17 to the hook 12 is referred to as the load rope 11a, and the length of the load rope 11a is referred to as the lobe length. When the load 14 is not suspended from the hook 12, the suspended object 16 is only the hook 12.

The crane 1 shown in FIG. 1 shows a state when the transport operation of the suspended object 16 is stopped, and the suspended object 16 is located vertically below the center 17a of the point sheave 17 arranged at the tip of the boom 2, and is suspended by the hoisting rope 11a without swinging. In the crane 1 shown in FIG. 1, the position where the suspended object 16 is assumed to be suspended from the boom 2 without swinging (the position on the reference line VL extending vertically downward from the center 17a of the point sheave 17) is the reference position of the suspended object 16. For convenience of explanation, the center 17a of the point sheave 17 is the suspension position of the suspended object 16 on the boom 2. In the crane 1 shown in FIG. 2, when considering the swing of the suspended object 16 in the left-right direction (direction along the Y axis), the position where the suspended object 16 is assumed to be suspended from the boom 2 without swinging (the position on the imaginary line extending vertically downward from the center position of the point sheave 17 in the left-right direction) is the reference position. In addition, in the crane 1 shown in FIG. 1, "on-duty" refers to the time when the boom 2 is moved relative to the ground surface of the crane 1, and the suspended load 16 is moved to a specified location by moving the load rope 11a. For example, "on-duty" refers to the time when the crane 1 is raised and lowered, or when the load rope 11a is wound up and down. Furthermore, "on-duty" does not include the time when the crane 1 is equipped with a perimeter monitoring device and the surroundings are monitored by the perimeter monitoring device.

As shown in Figures 1 and 3, a camera 4 serving as a detector is suspended from the tip of the boom 2 via a mounting fixture 18. The mounting fixture 18 has a base 20 fixed to the boom 2, a support 21 with one end rotatably supported by the base 20, and a cover 22 fixed to the other end of the support 21. The mounting fixture 18 maintains a position in which the support 21 and cover 22 face downwards due to their own weight, regardless of the raising and lowering operation of the boom 2. The camera 4 is stored inside the cover 22. As a result, the camera 4 maintains a position facing downwards, similar to the support 21 and cover 22 of the mounting fixture 18, regardless of the raising and lowering operation of the boom 2.

The camera 4 captures images of the hanging object 16 and the work site around the hanging object 16, and transmits the acquired image data to the control unit 23.

FIG. 4 is a block diagram showing the functional configuration of the crane 1.
As shown in FIG. 4, in addition to the above configuration, the crane 1 is equipped with a control unit 23, a drive unit 24, an operation unit 25, a display unit 26, a communication unit 27, a camera (detection unit) 4, and a memory unit 28.

The control unit 23 is configured, for example, with a CPU (Central Processing Unit) and controls the operation of each part of the crane 1. The control unit 23 includes the functions of an ECU (Electronic Control Unit) and is disposed on the upper rotating body 6. Specifically, the control unit 23 operates the drive unit 24 based on operation input by the operator, etc., and executes various processes in cooperation with programs 31 (31a to 31c) and the like that are pre-stored in the memory unit 28 described below.

The drive unit 24 is a drive source that operates each part of the crane 1, and includes the above-mentioned hoisting winch 10, hoisting winch 13, and rotating device 30 of the upper rotating body 6, as well as various other motors and actuators.
The operation unit 25 is an operating means through which an operator performs various operations. The operation unit 25 includes, for example, a handle, pedals, levers, various buttons, etc., and outputs operation signals to the control unit 23 according to the contents of these operations.

The display unit 26 is, for example, a liquid crystal display, an organic electroluminescence display, or other display, and displays images and various information of the hanging object 16 and the work site around the hanging object 16 based on a display signal input from the control unit 23. The display unit 26 may be a touch panel that also serves as a part of the operation unit 25.
The communication unit 27 is a communication device capable of transmitting and receiving various types of information to and from, for example, an information terminal (not shown).

As described above, the camera 4 as the detection unit outputs image data of the suspended object 16 and the work site around the suspended object 16 to the control unit 23. If the camera 4 has a distance measurement function, it acquires distance data to the suspended object 16 and outputs the distance data to the control unit 23. The detection unit may use a monocular camera, a stereo camera, a laser sensor such as LiDAR, or a GNSS (Global Navigation Satellite System). The distance data to the suspended object 16 is the distance data from the camera 4 to the hook 12 when the load 14 is not suspended from the hook 12. The distance data to the suspended object 16 may be the distance data from the camera 4 to the hook 12 even when the load 14 is suspended from the hook 12. In this embodiment, the camera 4 is disposed on the tip side of the boom 2, but is not limited to this, and is disposed in a position where image data of the suspended object 16 and the work site around the suspended object 16 can be acquired (for example, the middle part of the boom 2, the lower end of the boom 2, the upper rotating body 6).

The storage unit 28 is a memory configured, for example, by RAM (Random Access Memory) or ROM (Read Only Memory), and stores various programs and data, and also functions as a work area for the control unit 23. In this embodiment, the storage unit 28 pre-stores an anti-sway processing program 31 for executing anti-sway processing (see FIG. 8) for the suspended object 16, which will be described later. This anti-sway processing program 31 includes a suspended object position measurement program 31a, an obstacle detection program 31b, and a boom operation control program 31c.

The hanging object position measurement program 31a uses image data acquired by the camera 4 to calculate the maximum amplitude, swing direction, and swing period of the hanging object 16.

The obstacle detection program 31b uses image data acquired by the camera 4 to detect obstacles (objects) that may collide with the suspended object 16, and determines the direction in which the suspended object 16 should be prevented from swinging. For example, the obstacle detection program 31b uses image data acquired by the camera 4 to calculate the horizontal distance L (the shortest distance in the X-Y plane in FIG. 5) between the position of the suspended object 16 at the maximum amplitude and a surrounding structure (object) 32 at the work site. The obstacle detection program 31b then compares the horizontal distance L with a predetermined control dimension La, and if the horizontal distance L is equal to or smaller than the control dimension La, it recognizes the surrounding structure (object) 32 as an obstacle. Next, the obstacle detection program 31b determines the direction in which the suspended object 16 should be prevented from swinging in the anti-sway process described later as a direction away from the obstacle (32) (the -X direction in FIG. 5), and moves the hanging position (17a) of the boom 2 in the first control described later in a direction away from the obstacle (32).

The boom operation control program 31c calculates the boom 2 rotation angle and/or boom 2 elevation angle to suppress the swing of the hanging object 16 based on the calculation results of the hanging object position measurement program 31a and the determination results of the obstacle detection program 31b.

(First example of anti-vibration processing)
Fig. 6 is a diagram showing a first example of the anti-sway processing of the suspended object 16, showing the case of vibration pattern I in which the maximum amplitude direction of the suspended object 16 is along the X-axis direction. Fig. 6 also shows the anti-sway processing of the suspended object 16 when an obstacle (32) is not detected by the obstacle detection program 31b. Fig. 6(a) is a plan view showing the first example of the anti-sway processing of the suspended object 16, and Fig. 6(b) is a side view showing the first example of the anti-sway processing of the suspended object 16.

As shown in FIG. 6, the boom operation control program 31c calculates the boom 2 elevation angle by noting that the vibration of the hanging object 16 is suppressed when the center 17a of the point sheave 17 (the fulcrum of the amplitude of the hanging object 16, and the hanging position of the hanging object 16 on the boom 2) is brought closer to the maximum amplitude position of the hanging object 16 (a position shifted from the reference position, which is a position on the reference line VL).

In this embodiment, the anti-sway of the suspended object 16 is performed twice to prevent the amplitude of the vibration of the suspended object 16 from being equal to or less than a predetermined set value (see steps S4 to S9 in FIG. 8). That is, the first control, which is the first anti-sway of the suspended object 16, is performed when the suspended object 16 moves from the reference position (first reference position) on the reference line VL (first reference line (VL1)) toward the maximum amplitude position. In this first control, when the suspended object 16 is at a first displaced position 16a1 displaced from the first reference position, the boom operation control program 31c calculates the hoisting angle of the boom 2 based on the calculation results of the suspended object position measurement program 31a (the maximum amplitude, swing direction, swing period of the suspended object 16), etc., so that the boom 2 approaches the first displaced position 16a1 (so that the hanging position 17a can move from a position on the first reference line (VL1) to a hanging position 17a1 at a distance of m1 (on the second reference line VL2)). This first control is performed when the crane 1 is not in operation, and the hanging position (17a) is brought closer to the suspended object 16. Then, the control unit 23 operates the hoisting winch 10 based on the calculation results of the boom operation control program 31c, and hoists the boom 2. The boom 2 is tilted when the hanging position (17a) is moved toward the tip side in the +X direction, and is raised when the hanging position (17a) is pulled back from the tip side in the +X direction. In the first control, the timing of the movement of the hanging position (17a) is when the hanging object 16 moves from the reference position on the first reference line VL1 to the maximum amplitude position. By moving it at such a timing, the boom 2 can be moved in the same direction as the movement direction of the hanging object 16, making it easier to suppress the vibration. In addition, between the first control and the second control described later, there is a neutral state (neutral brake state) in manual operation. In this case (neutral brake state), if it is a hydraulic crane, a hydraulic brake will be applied to the operation of the crane 1. The set value of the amplitude of the hanging object 16 is arbitrarily determined according to the situation at the work site, etc.

The second control, which is the second anti-sway control of the suspended object 16, is a control in the opposite direction to the first control, and when the suspended object 16 is at the second offset position 16a2 that is offset from the second reference position on the second reference line Vl2, which is the reference position after the first control, the boom 2 is operated to approach the second offset position 16a2. That is, this second control calculates the distance m2 (the distance to the suspended position (17a2)) from the suspension position (17a1) at the end of the first control to the maximum amplitude position (second offset position 16a2) of the next suspended object 16 by the boom operation control program 31c, and calculates the boom hoisting angle of the boom 2 corresponding to the distance m2 by the boom operation control program 31c. The control unit 23 operates the hoisting winch 10 based on the calculation result of this boom operation control program 31c, and hoists the boom 2. In addition, in this second control, the timing of movement of the hanging position (17a1) is when the hanging object 16 moves from the second reference position on the second reference line VL2 at the hanging position (17a1) at the end of the first control to the maximum amplitude position (position of distance m2). In addition, the second control is not limited to the case of control in the opposite direction to the first control, and the hanging position (17a1) at the end of the first control may be moved in accordance with the movement direction of the hanging object 16 returning to the first deviation position 16a1 side (it may be controlled in the same direction as the first control). In other words, the second control may be performed in the same direction as the first control after the hanging object 16 passes the second reference line (VL2) twice after being in a neutral state (neutral brake state) between the first control and the second control.

In this type of anti-sway processing for the hanging object 16, the anti-swaying of the hanging object 16 is performed in multiple steps, so the acceleration acting on the hanging object 16 is smaller than when the anti-swaying of the hanging object 16 is performed in one step, making it possible to smoothly and reliably prevent the hanging object 16 from swinging.

In addition, in the anti-sway process for the hanging object 16 shown in FIG. 6, the second control moves the hanging position (17a) in the opposite direction to the first control, so the movement distance of the hanging position (17a) can be reduced.

As described above, in the second control of the anti-sway process for the suspended object 16 shown in FIG. 6, the timing of movement of the hanging position (17a1) is when the suspended object 16 moves from the second reference position on the second reference line VL2 at the hanging position (17a1) at the end of the first control to the maximum amplitude position (position at distance m2). Therefore, the anti-sway process for the suspended object 16 according to this embodiment can be expected to have a significant anti-sway effect.

Note that the anti-sway process for the suspended object 16 shown in FIG. 6 is performed in the +X direction, but is not limited to this and may be performed in the -X direction. In this way, when the anti-sway process for the suspended object 16 is performed in the -X direction, the movement of the suspension position (17a) in FIG. 6(a) is performed by raising the boom 2.

The anti-sway process for the suspended object 16 shown in FIG. 6 is performed in two separate steps, the first control and the second control, but is not limited to this and may be performed in three or more separate steps, such as when the amplitude of the suspended object 16 does not fall below a predetermined set value (see steps S8 to S11 in FIG. 8). In this way, when the anti-sway process for the suspended object 16 is performed in three or more separate steps, the movement distance of the hanging position (17a) is determined to be an optimal value according to the number of anti-sway processes. Note that, although the first example of the anti-sway process illustrates a case where the process is performed based on the amplitude of the suspended object 16, the process is not limited to this and may be performed based on the number of anti-sway processes.

In addition, it is preferable to perform the anti-sway process of the suspended object 16 in an even number of times so that the forces acting on the hanging position (17a) are easily offset. For example, the anti-sway process of the suspended object 16 may be performed in multiple sets of the first and second controls, with the first and second controls being one set. In this way, when multiple sets of the first and second controls with opposite control directions are performed, the movement distance of the boom 2 at the start and end of the anti-sway process is reduced, so that the position is less likely to shift before and after the start. In addition, there is no need to secure a large space when the crane is not in operation, which is particularly effective when the crane is not in operation. Note that the anti-sway process of the suspended object 16 may be completed without performing the second control if the amplitude of the suspended object 16 becomes equal to or less than the set value at the end of the first control after one set of the first and second controls.

In addition, the anti-sway process for the hanging object 16 may be performed multiple times using either the first control or the second control.

In addition, in this embodiment, the control unit 23 and the like automatically prevents the hanging object 16 from swaying using the anti-sway processing program 31, but the present invention is not limited to this, and the operator may manually operate the operation unit 25 to bring the hanging position (17a) closer to the hanging object 16. In such a case where the operator manually operates the crane 1, for example, the display unit 26 gives instructions to the operator, and the operator actually performs the operation. Note that in FIG. 6(b), the hanging position (17a2) and the hanging object 16 may not completely coincide with each other, and there may be a misalignment between the hanging position (17a2) and the hanging object 16.

(Second example of anti-sway processing)
Fig. 7(a) is a plan view showing a second example of the anti-sway processing of the suspended object 16, showing the case of vibration pattern II in which the maximum amplitude direction of the suspended object 16 is along the Y-axis direction. Fig. 7(a) also shows the anti-sway processing of the suspended object 16 when an obstacle (32) is not detected by the obstacle detection program 31b. Note that in the explanation of this second example of the anti-sway processing of the suspended object 16, explanations common to the explanation of the first example will be omitted as appropriate.

As shown in FIG. 7(a), the boom operation control program 31c calculates the rotation angle of the boom 2 by noting that the vibration of the suspended object 16 is suppressed when the center 17a of the point sheave 17 (the fulcrum of the amplitude of the suspended object 16, and the hanging position of the suspended object 16 on the boom 2) is brought closer to the maximum amplitude position of the suspended object 16. In addition, this second example is designed to perform anti-sway processing of the suspended object in the +Y axis direction, and the first and second controls are performed in the same way as the first example.

In this second example, the movement of the hanging position (17a) is performed by rotating the boom 2, and the boom operation control program 31c calculates the rotation angle of the boom 2 based on the calculation results of the hanging object position measurement program 31a (maximum amplitude, swing direction, swing period of the hanging object 16), etc. Then, the control unit 23 operates the rotation device 30 based on the calculation results of this boom operation control program 31c, and rotates the upper rotating body 6 and the boom 2.

The second example described above can prevent the hanging object 16 from swinging in the same manner as the first example.
In the second example, anti-sway processing of the suspended object 16 is performed in the +Y axis direction, but this is not limited thereto, and anti-sway processing of the suspended object 16 can also be performed in the -Y axis direction.
In the second example, when the boom 2 is rotated, it is in a neutral state (swing neutral free state) in the manual operation between the first control and the second control. In this swing neutral free state, the boom 2 rotates by the inertia of the upper swing body 6 (oil circulates in response to the rotation by the inertia of the swing hydraulic motor).
In addition, in the neutral state of the second example, when the boom 2 rotates due to the inertia of the upper rotating body 6, the rotation of the boom 2 may be braked. For example, a hydraulic brake may be provided separately for the hydraulic motor for rotation, and the brake may be applied by this hydraulic brake. In this case, the rotation speed of the boom 2 is further reduced by the hydraulic brake.

(Third example of anti-sway processing)
Fig. 7(b) is a plan view showing a third example of the anti-sway processing of the suspended object 16, and shows the case of vibration pattern III in which the maximum amplitude direction of the suspended object 16 is tilted by θ in the counterclockwise direction with respect to the X-axis direction. Fig. 7(b) also shows the anti-sway processing of the suspended object 16 when an obstacle (32) is not found by the obstacle detection program 31b. Note that in the explanation of this third example of the anti-sway processing of the suspended object 16, explanations common to the explanation of the first example will be omitted as appropriate.

As shown in FIG. 7(b), the boom operation control program 31c calculates the swivel angle and hoisting angle of the boom 2 by focusing on the fact that the vibration of the suspended object 16 is suppressed when the center 17a of the point sheave 17 (the fulcrum of the amplitude of the suspended object 16, and the hanging position of the suspended object 16 on the boom 2) is brought closer to the maximum amplitude position of the suspended object 16. In addition, this third example is designed to perform anti-sway processing of the suspended object in the first quadrant, and the first and second controls are performed in the same way as the first example.

In this third example, the movement of the hanging position (17a) is performed by the rotation and raising and lowering of the boom 2, and the boom operation control program 31c calculates the rotation angle and the raising and lowering angle of the boom 2 based on the calculation results of the hanging object position measurement program 31a (maximum amplitude, swing direction, and swing period of the hanging object 16). Then, the control unit 23 operates the rotation device 30 based on the calculation results of this boom operation control program 31c to rotate the upper rotating body 6 and the boom 2, and operates the raising and lowering winch 10 based on the calculation results of the boom operation control program 31c to raise and lower the boom 2.

The third example can prevent a suspended object from swinging in the same manner as the first example.
In the third example, anti-sway processing of the suspended object 16 is performed in the first quadrant, but this is not limited thereto, and anti-sway processing of the suspended object 16 can also be performed in the third quadrant.
Moreover, the third example can be applied to the case of vibration pattern IV in which the maximum amplitude direction of the suspended object 16 is inclined by an angle θ in the clockwise direction with respect to the X-axis direction.

(Flow of anti-sway processing)
FIG. 8 is a flow chart showing the flow of a process for preventing the swing of the suspended object 16 in the crane 1 according to this embodiment.

In this embodiment, the anti-sway processing of the hanging object 16 is executed by the control unit 23 reading and deploying the anti-sway processing program 31 from the memory unit 28, for example, based on the operation of the operator. Note that the anti-sway program 31 may also be read and deployed after other automatic operations, not based on the operation of the operator.

First, the maximum amplitude, swing direction, and swing period of the hanging object 16 are calculated by the hanging object position measurement program 31a (step S1). Image data acquired by the camera 4 is used to calculate the maximum amplitude, etc. of the hanging object 16.

Next, the obstacle detection program 31b identifies obstacles that may collide with the suspended object 16 (step S2). The obstacle detection program 31b identifies obstacles using image data acquired by the camera 4.

If the obstacle detection program 31b determines that an obstacle is present, the obstacle detection program 31b determines the direction of the deflection to avoid collision with the obstacle (step S3).

If the obstacle detection program 31b determines that there is no obstacle, the anti-sway process (steps S4 to S9) of the suspended object 16 is executed in a pre-set anti-sway direction (see the first to third examples of the anti-sway process of the suspended object), and if the obstacle detection program 31b determines that there is an obstacle, the anti-sway process of the suspended object 16 is executed in the anti-sway direction determined in step 3 (steps S4 to S9). Note that if an obstacle is identified by the obstacle detection program 31b after the anti-sway process has been started (for example, after the first control has ended), the second control in the direction in which the obstacle was identified is not performed. In addition, in the first control, the first deviation position 16a1 is located on the opposite side of the first reference position to an object (obstacle) that may come into contact with the suspended object 16 among the objects detected by the camera (detection unit) 4. In this way, the anti-sway process for the suspended object 16 in this embodiment moves the suspended object 16 to avoid obstacles, which makes it possible to avoid collisions between the suspended object 16 and obstacles and allows for safer work.

The anti-sway process first detects the first reference position and the first offset position 16a1 of the suspended object 16 (step S4). The detection of the first reference position and the first offset position 16a1 of the suspended object 16 is performed, for example, by the camera 4 or an operator. At this point, it is possible to determine whether or not an obstacle is present.

Next, the boom 2 is moved from the first reference position toward the first shifted position 16a1 (step S5).

Next, the camera 4, an operator, or the like detects that the hanging position 17a (reference position) of the boom 2 is located on the opposite side of the hanging position 17a1 (first reference position) of the boom 2 from the first offset position 16a1 (step S6). At this point, it is possible to determine whether or not an obstacle is present.

Next, the boom 2 is moved from the second reference position toward the second shifted position 16a2 (step S7).

Next, the amplitude of the suspended load 14 (hanging object 16) is detected by the camera 4, an operator, etc. (step S8).

Next, it is determined whether the amplitude of the suspended load 14 (hanging object 16) detected in step S8 is equal to or less than a preset value (set value) (step S9), and if it is determined that the amplitude is equal to or less than the set value, the anti-sway process (first control and second control) of the hanging object 16 is terminated. As a result, the sway of the hanging object 16 is reliably suppressed. The anti-sway process may be stopped when a predetermined number of processes (multiple times) have been completed. The anti-sway process may also be stopped when the amplitude of the hanging object 16 is equal to or less than a predetermined set value and the number of anti-sway processes, including the first control and the second control, is an even number. (In this case, if the result in step S9 of FIG. 9 is NO, the process returns to step S4 via the dotted line.) When the conditions are set in this way, the movement distance before and after the anti-sway process can be made smaller, and the sway can be more reliably suppressed.

On the other hand, if it is determined that the amplitude exceeds the set value (step S9), the Nth reference position and the Nth deviation position are detected (step S10), the boom 2 is moved from the Nth reference position toward the Nth deviation position (step S11), the amplitude of the suspended load 14 (hanging object 16) is detected (step S8), and the anti-sway processing of steps S10, S11, S8, and S9 is repeated until the amplitude becomes equal to or less than the set value (step S9). Note that in this embodiment, N is a number equal to or greater than 3, and increases by 1 each time the anti-sway processing is performed.

The anti-sway processing according to the above embodiment is an example in which the amplitude of the hanging object 16 is controlled to be equal to or less than a set value, but this is not limited to this, and it may be controlled by the number of times the anti-sway processing is performed (a number of times that is arbitrarily set in advance). For example, the number of times the anti-sway processing is performed may be two times, as shown in steps S4 to S7 in Figures 6, 7, and 8.

(Effects of this embodiment)
The crane 1 of this embodiment can effectively suppress the swinging of the suspended object 16 when the transport operation of the suspended object 16 is stopped.

In addition, the crane 1 of this embodiment is designed to perform multiple anti-sway processes to prevent the suspended object 16 from swaying. Therefore, even if the suspended object 16 is composed of a hook 12 and a suspended load 14, the acceleration acting on the hook 12 and the suspended load 14 can be reduced compared to when the suspended object 16 is prevented from swaying in a single anti-sway process, and double vibrations can be prevented from occurring between the hook 12 and the suspended load 14.

Other Embodiments
In the crane 1 according to the present invention, the installation angle of the camera 4 may be variably set by a movable mechanism (not shown) such as a servo motor.
In the crane 1 of this embodiment, the state of the suspended load is detected by the camera 4 and the anti-sway process is performed, but the operator may monitor the state of the suspended load and operate the crane 1 by an operation method that performs the first control and the second control described above. In this case as well, the sway of the suspended load 16 can be effectively suppressed when the transport operation of the suspended load 16 is stopped.

In addition, the present invention is not limited to any particular type of crane, and may include any type of crane, including mobile cranes such as crawler cranes, wheel cranes, and truck cranes, as well as port cranes, overhead cranes, gantry cranes, unloaders, and fixed cranes.
The present invention also includes in the crane a backhoe which has a boom and an arm, a rope suspended from the arm, and a hook attached to the rope.
In addition, the details shown in the above embodiment can be modified as appropriate without departing from the spirit of the invention.

1 Crane 2 Boom 16 Hanging object 16a1 First offset position 16a2 Second offset position

Claims (8)

A crane having a boom and a suspended load suspended from the boom,
In a plane coordinate system viewed vertically downward from above the crane, if the position at which the suspended object is suspended from the boom without swinging is defined as the reference position of the suspended object,
a first control for operating the boom so as to approach the first displaced position in the plane coordinate system when the suspended object is at a first displaced position displaced from a first reference position;
a second control for operating the boom so as to approach the second displaced position in the plane coordinate system when the suspended object is at a second displaced position displaced from a second reference position that is a reference position after the first control;
Crane performing the work. The crane according to claim 1, wherein the second control is performed after the suspended object is positioned on the opposite side of the second reference position from the first shifted position. The crane according to claim 2, wherein the second control is performed when the suspended object is in a second shifted position on the opposite side of the second reference position from the first shifted position. The crane according to claim 3, wherein when the first control and the second control form one set, the first control and the second control are repeated multiple times. The crane according to any one of claims 1 to 4, wherein the first control and the second control are terminated when the amplitude of the suspended object becomes equal to or less than a predetermined value. A detection unit that detects objects around the hanging object,
In the first control, a first deviation position is located on an opposite side of the first reference position with respect to an object that may come into contact with the hanging object among the objects detected by the detection unit.
A crane according to any one of claims 1 to 4. The crane according to any one of claims 1 to 4, wherein the timing for starting the first control or the second control is when the suspended object is moving from the reference position to the maximum amplitude position. The crane according to any one of claims 1 to 4, wherein the first control is initiated when the boom is not being rotated or raised/lowered, and the suspended object is not being hoisted or lowered.

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