Winch drum monitoring device and winch drum

Abstract

To highly accurately detect a layer number of a wire rope of a winch drum.SOLUTION: A monitoring device of a winch drum for monitoring a state of the winch drum 361 comprises an imaging unit 628 which images the winch drum 361. The winch drum 361 comprises: a winding part 362 around which a wire rope 32 is wound; and flange parts 363, 364 which are provided on both sides of the winding part 362. A first mark 45 is provided on the inner side surfaces of the flange parts 363, 364. The monitoring device includes a specification unit 611 which specifies a layer number of winding of the wire rope 32 around the winding part 362 by detecting the first mark 45 in a photographed image captured by an imaging unit.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a winch drum monitoring device and a winch drum.

Background Art

[0002] In a working machine that winds and unwinds a wire by a winch drum such as a crane, conventionally, it has been proposed to photograph the winch drum with a camera and detect the number of layers of the wound wire rope (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the above prior art, when disturbance factors such as dirt on the wire rope or adhesion of oil occur, the number of layers cannot be accurately detected.

[0005] An object of the present invention is to accurately detect the number of layers of a wire rope of a winch drum.

Means for Solving the Problems

[0006] The present invention is a winch drum monitoring device for monitoring the state of a winch drum, It is provided with an imaging unit that images the winch drum, The winch drum has a winding portion around which a wire rope is wound, and flange portions provided on both sides of the winding portion, A first mark is provided on the inner surface of the flange portion, A specifying unit that specifies the number of layers in which the wire rope is wound around the winding portion by detecting the first mark in the captured image captured by the imaging unit, It has a detecting means for detecting the rotational phase of the winch drum, The specifying unit specifies the number of layers based on the captured image when a specific rotational phase is detected by the detecting means configured as follows. Also, another aspect of the present invention is, A monitoring device for a winch drum that monitors the state of the winch drum, It is provided with an imaging unit that images the winch drum, The winch drum has a winding portion around which a wire rope is wound, and flange portions provided on both sides of the winding portion, A first mark is provided on the inner surface of the flange portion, It has a specifying unit that specifies the number of layers in which the wire rope is wound around the winding portion by detecting the first mark in the captured image captured by the imaging unit, The first mark is a plurality of marks corresponding to a plurality of layers of the wire rope wound in layers on the winch drum, The first mark is provided on the inner side in the radial direction of the winch drum than the center of the wire rope diameter of the corresponding layer , and has such a configuration.

[0007] Also, the present invention relates to a winch drum, comprising a winding portion around which a wire rope is wound, and flange portions provided on both sides of the winding portion, wherein a first mark for specifying the number of layers of the wire rope wound around the winding portion is provided on the inner surface of the flange portion 、 The first mark is a plurality of marks corresponding to a plurality of layers of the wire rope wound in layers on the winch drum, The first mark is provided on the inner side in the radial direction of the winch drum than the center of the wire rope diameter of the corresponding layer , and is configured as such.

Advantages of the Invention

[0008] According to the present invention, it becomes possible to more accurately detect the number of layers of the wire rope wound around the winch drum.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Mode for Carrying Out the Invention

[0010] [Outline of Crane] Figure 1 is a side view of a crane as a work machine equipped with a monitoring device for a winch drum according to an embodiment of the present invention. The crane 1 is a so-called mobile crawler crane. Regarding the description of the crane 1, the vehicle forward direction is "front", the reverse direction is "rear", and with the front facing forward, the left side is "left" (the back side of the paper in Figure 1) and the right side is "right" (the front side of the paper in Figure 1). Also, it includes a lower traveling body 2 that travels and an upper slewing body 3 that slews on it. In principle, when not particularly mentioned, the directions of each part are described assuming that the lower traveling body 2 and the upper slewing body 3 are in a state where the front-rear directions coincide (reference posture).

[0011] As shown in Figure 1, the crane 1 includes a crawler-type lower traveling body 2 that can self-propel, an upper slewing body 3 that is rotatably mounted on the lower traveling body 2, and a boom 4 that is attached to the front side of the upper slewing body 3 so as to be able to rise and fall.

[0012] The lower traveling body 2 includes a main body body 21 and crawlers 22 provided on both the left and right sides of the main body body 21. The left and right crawlers 22 are rotationally driven by traveling hydraulic motors (not shown), respectively.

[0013] A boom 4 is attached to the front side of the upper slewing body 3 so as to be able to rise and fall. A sheave 43 for guiding a hoisting rope 32 as a wire rope is rotatably attached near the tip of the upper side of the boom 4. Also, the lower end of a mast 31 is supported on the rear side of the boom 4 in the upper slewing body 3. The upper slewing body 3 is driven to slew around a vertical axis with respect to the lower traveling body 2 by a slewing hydraulic motor (not shown).

[0014] A cab 33 is arranged on the right front side of the upper slewing body 3. A counterweight 5 for balancing the weight of the boom 4 and the suspended load L is attached to the rear part of the upper slewing body 3. The number of counterweights 5 can be increased or decreased as necessary.

[0015] A hoisting winch 42 for raising and lowering the boom 4 is disposed near the counterweight 5, and a hoisting winch 36 for winding in and out the hoisting rope 32 is disposed on the front side thereof. The hoisting winch 36 winds in and out the hoisting rope 32 by a hoisting hydraulic motor (not shown) to raise and lower the hook 34 and the suspended load. Details of the winch drum 361 used for the hoisting winch 36 will be described later.

[0016] The mast 31 is provided with an upper spreader 35 at the upper end, and one end of the upper spreader 35 is connected to the other end of a pendant rope 44 whose one end is connected to the upper end of the boom 4. A lower spreader (not shown) is provided below the upper spreader 35. When a hoisting rope 37 as a wire rope wound around a plurality of times between them is wound in or out by the hoisting winch 42, the distance between the upper spreader 35 and the lower spreader changes, and the boom 4 rises and falls. The hoisting winch 42 is driven by a hoisting hydraulic motor (not shown).

[0017] [Crane control system] On the cab 33 of the upper revolving body 3 and the like, a control device 60 of the crane 1 is provided. FIG. 2 is a block diagram showing the control device 60 and its surrounding configuration. The control device 60 is a control terminal mounted on the crane 1, and in addition to controlling various operations such as the traveling, slewing, winding and unwinding of the hoisting rope 32 of the crane 1, it performs monitoring processing of the winding and unwinding of the hoisting rope 32 by the hoisting winch 36. The control device 60 includes a controller 61 configured to include an arithmetic processing unit having a CPU, a ROM and a RAM which are storage devices, and other peripheral circuits. The controller 61 includes a software module of a monitoring processing unit 611 that performs monitoring processing of the winding and unwinding of the hoisting rope 32 described later. Note that the monitoring processing unit 611 may be configured from hardware.

[0018] An input unit 621, a display device 622, an operation lever 624, and a memory 625 are connected to the controller 61, and these constitute the control device 60. Furthermore, a load cell 631, a boom angle sensor 632, a slewing amount sensor 633, a control valve 635, and an imaging device 628 are connected to the controller 61. The imaging device 628 is connected to the controller 61 via an image processing device 629.

[0019] The monitoring processing unit 611, the display device 622, the image processing device 629, and the imaging device 628 constitute a monitoring device for the winch drum that monitors the state of the winch drum 361 of the hoisting winch 36. Details of the functions of the monitoring processing unit 611 will be described later.

[0020] The input unit 621 is provided inside the cab 33 and is an input interface such as a touch panel, for example, and outputs a control signal corresponding to an operation by an operator to the controller 61. The operator can operate the input unit 621 to input the length of the boom 4, the type (weight) of the hook, and various other settings and operations necessary for control. The display device 622 is provided inside the cab 33, and includes, for example, a touch panel display that is also used as the input unit 621. Based on the control signal output from the controller 61, information such as the weight of the suspended load, the boom angle, and the slewing angle of the upper slewing body 3 is displayed on the display screen (see FIG. 8). Further, the display device 622 functions as a notification means for performing notification by display by the monitoring processing unit 611 described later.

[0021] The operation lever 624 is provided inside the cab 33. For example, an operation for causing the crane 1 to perform various operations is manually input, and a control signal corresponding to the operation amount of the operation lever 624 is input to the controller 61. For example, the operation lever 624 can perform operation inputs for the traveling operation of the lower traveling body 2, the slewing operation of the upper slewing body 3, the raising and lowering operation of the boom 4, the winding and unwinding of the hoisting rope 32 by the hoisting winch 36.

[0022] The load cell 631 is attached to the ends of the hoisting ropes 37 that are wound around the upper spreader 35 and the lower spreader a plurality of times. When the boom 4 is raised and lowered, the tension acting on the hoisting rope 37 is detected, and a control signal corresponding to the detected tension is output to the controller 61. Note that the load cell 631 may be arranged anywhere as long as it can indirectly measure the lifting force of the boom 4. For example, it may be provided at the attachment position (not shown) of the pendant rope 44 at the tip of the boom 4 to detect the tension applied to the pendant rope 44.

[0023] The boom angle sensor 632 is attached to the base end side of the boom 4, detects the raising and lowering angle of the boom 4 (hereinafter also referred to as the boom angle), and outputs a control signal corresponding to the detected boom angle to the controller 61. The boom angle sensor 632 detects, for example, the angle with respect to the horizontal plane, i.e., the angle with respect to the ground, as the boom angle.

[0024] The turning amount sensor 633 is attached between the lower traveling body 2 and the upper slewing body 3, detects the slewing angle of the upper slewing body 3, and outputs a control signal corresponding to the detected slewing angle to the controller 61. The turning amount sensor 633 detects, for example, the angle around the vertical axis as the turning angle.

[0025] The control valve 635 is composed of a plurality of valves that can be switched according to a control signal from the controller 61. For example, the control valve 635 includes valves that control the rotational drive of the left and right crawlers 22 of the lower traveling body 2, valves that control the slewing operation of the upper slewing body 3, valves that control the rotational drive of the hoisting winch 42, valves that control the rotational drive of the winch 36, and the like.

[0026] [Imaging device] The imaging device 628 is a camera having an image sensor such as a CCD (Charge-Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) and an optical system. In addition, the imaging device 628 is provided with a color filter and can capture a color image. That is, this imaging device 628 can identify and detect the color of a predetermined object within the imaging range. Note that the imaging device 628 may be configured to mount an image sensor that can detect a plurality of colors without using a color filter.

[0027] The image processing device 629 converts the detected image of the imaging device 628 into digital data. In addition, the image processing device 629 performs processing such as image processing and detection of a predetermined object on the detected image converted into digital data.

[0028] [Winch drum] FIG. 3 is a perspective view of the winch drum 361, and FIG. 4 is an axial cross-sectional view of the winch drum 361 showing the laminated state of the hoisting rope 32. In the following description, the "axial direction" refers to the direction along the central axis of the winch drum 361, and the "radial direction" refers to the direction perpendicular to the central axis of the winch drum 361.

[0029] As shown in FIGS. 3 and 4, the winch drum 361 has a drum body 362 as a winding portion around which the hoisting rope 32 is wound, and two flange portions 363 and 364 in the shape of flanges provided at both ends of the drum body 362, and is rotatably supported around the central axis. Then, on the drum body 362 of the winch drum 361, a layer around which the hoisting rope 32 is wound toward one flange portion 363 side and a layer around which the hoisting rope 32 is wound toward the other flange portion 364 side are alternately and repeatedly laminated. And the number of layers up to the outermost side of the hoisting rope 32 between the two flange portions 363 and 364 is the "number of layers" in the "layer arrangement state". Also, the number of turns around which the outermost hoisting rope 32 is wound from the end to the rope payout portion is the "number of rows" in the "layer arrangement state".

[0030] In FIG. 4, reference sign a indicates the position of the first row (the first row) of the hoisting rope 32 in each layer. For example, in the odd-numbered layers of the hoisting rope 32, the first row a is on the side of the other flange portion 364 (the left flange portion in the example of FIG. 4). Also, in the even-numbered layers, the first row a is on the side of one flange portion 363 (the right flange portion in the example of FIG. 4).

[0031] On the inner surfaces (the opposing surfaces of the flange portions 363 and 364) of the flange portions 363 and 364 on both sides of the winch drum 361, a first mark 45 is provided for detecting the number of layers of the hoisting rope 32 by the imaging device 628. A plurality of first marks 45 are provided, and each of them corresponds to each layer of the hoisting rope 32. The first mark 45 is arranged so as to be hidden by the hoisting rope 32 wound around the first row a of each layer. Therefore, when the hoisting rope 32 is wound up to the first row a for each layer, the first mark 45 becomes in a state where it cannot be visually or optically detected. In this way, the first mark 45 can detect from its non-detection state that the hoisting rope 32 of each layer is wound up to the last row. Note that the fact that the first mark 45 is hidden by the hoisting rope 32 of the first row a indicates that at least the hoisting rope 32 is wound up to the last row of the layer one layer inside the layer to which the first row a belongs.

[0032] In the following description, when comprehensively explaining a plurality of first marks 45 corresponding to a plurality of layers individually, it is described as "the first mark 45", and when individually explaining the first mark 45 corresponding to an arbitrary layer of the hoisting rope 32, the layer number is added to the first digit of the reference sign and described. For example, in the case of the corresponding first mark of the second layer of the hoisting rope 32, it is described as "the first mark 452".

[0033] FIG. 5 is an enlarged cross-sectional view of the formation position of the first mark 45 of each flange portion 363, 364. The first mark 45 is colored with a color different from the surface color (hereinafter referred to as the surrounding color) of the inner surface of each flange portion 363, 364 around the first mark 45. Note that the color different from the surrounding color in the first mark 45 indicates a color distinguishable from the surrounding color by the imaging device 628. For example, the first mark 45 only needs to have at least one of the hue, chroma, and lightness, which are the three color attributes, different from the surrounding color.

[0034] For example, when making the hue different, it is preferable to select a hue one or more apart in the 12-hue ring such as the Munsell color system or the Ostwald color system with respect to the surrounding color. Also, when making the chroma and lightness different, it is preferable to use paired frequencies in the Munsell color chips. Also, the color different from the surrounding color in the first mark 45 includes a transparent color and a structural color. Furthermore, the first mark 45 may be formed of a reflective material capable of reflecting wavelength light in a specific wavelength band.

[0035] Each first mark 45 is disposed radially inward of the center 32c of the cross-section of the hoisting rope 32 located in the corresponding layer (the layer in which the hoisting rope 32 of the first row a of the corresponding layer hides the first mark 45) with respect to the winch drum 361. Further, each first mark 45 is disposed radially outward of the center 32c of the cross-section of the hoisting rope 32 located in a layer two layers inward from the corresponding layer with respect to the winch drum 361. Thereby, when the first row a of the hoisting rope 32 of the corresponding layer is wound, each first mark 45 is covered by the hoisting rope 32 and becomes invisible from the radially outer side of the winch drum 361. That is, the imaging device 628 images from the radially outer side of the winch drum 361, and can recognize whether or not all rows have been wound for the layer one layer inside the corresponding layer of the hoisting rope 32 based on whether or not the first mark 45 is detected within the imaging range.

[0036] As described above, in the winding operation, the hoisting rope 32 is folded back by each flange portion 363, 364 and moves to the outer layer. Therefore, the first row a of each layer is on the flange portion 363 side for the even-numbered layers and on the flange portion 364 side for the odd-numbered layers. Therefore, as shown in FIG. 4, the first marks 452, 454 corresponding to the second and fourth layers, which are even-numbered layers, are provided on the inner surface of the flange portion 363, and the first marks 453, 455 corresponding to the third and fifth layers, which are odd-numbered layers, are provided on the inner surface of the flange portion 364. Note that the first marks 452, 454 corresponding to the second and fourth layers, which are even-numbered layers, are provided on the flange portion 363 and correspond to inner layer marks corresponding to a predetermined winding layer (even winding layer) of the hoisting rope 32, and the first marks 453, 455 corresponding to the third and fifth layers, which are odd-numbered layers, are provided on the flange portion 364 and correspond to outer layer marks corresponding to a winding layer (odd winding layer) outside the predetermined winding layer (even winding layer). Also, the first marks 453, 455 corresponding to the third and fifth layers, which are odd-numbered layers, and the inner layer marks, and the first marks 452, 454 corresponding to the second and fourth layers, which are even-numbered layers, can also be regarded as outer layer marks.

[0037] In the crane 1 shown in this embodiment, in principle, the hoisting rope 32 wound around the entire first layer of the winch drum 361 is always operated to maintain the state of being wound without being further paid out. Under such operation, the first mark 45 corresponding to the first layer of the hoisting rope 32 is always hidden behind the hoisting rope 32 in the first row a of the first layer and is not recognized from the outside. Therefore, the first mark 45 corresponding to the first layer can be omitted. However, it goes without saying that the first mark 45 corresponding to the first layer may be provided on the flange portion 364.

[0038] Further, as shown in FIG. 5, the first mark 45 has a concave shape or a concave-convex shape and is provided at the inner bottom of the recess 45a on the inner side surface of each of the flange portions 363 and 364. Thereby, the contact with the hoisting rope 32 is suppressed, and a decrease in detectability due to the surface of the first mark 45 being scraped can be suppressed. It is preferable that the inner diameter of the recess 45a and the outer diameter of the first mark 45 are smaller than the outer diameter of the hoisting rope 32 so that the hoisting rope 32 does not enter the inside of the recess 45a.

[0039] As shown in FIG. 4, the imaging device 628 is arranged on the radially outer side of the winch drum 361 and at the central portion in the axial direction of the winch drum 361 such that its optical axis is substantially perpendicular to the rotation axis of the winch drum 361. Further, the monitoring processing unit 611 described later monitors the layer arrangement state of the winch drum 361 based on the captured image when the phase (rotation angle) of the winch drum 361 with respect to the imaging device 628 is a specified phase.

[0040] The above-mentioned specified phase should be a phase in which all the first marks 45 not hidden by the hoisting rope 32 can be captured well by the imaging device 628. Each of the above-described first marks 45 is arranged in a row on the inner surfaces of the respective flange portions 363 and 364 along a radius having the same phase as that of the winch drum 361 (for example, the vertical direction along the plane of FIG. 4). On the other hand, each of the first marks 45 is arranged facing the imaging device 628 side, and a phase in which the radial direction in which the first marks 45 are arranged is parallel to the direction of the optical axis of the imaging device 628 is defined as a predetermined phase. When the winch drum 361 is in the above-described predetermined phase, when viewed from the imaging device 628 side, the first marks 45 on the inner surfaces of the respective flange portions 363 and 364 of the winch drum 361 are arranged in a row facing the imaging device 628 side, and the imaging device 628 can satisfactorily image each of the first marks 45.

[0041] On the outer peripheral portion of one of the flange portions 363 of the winch drum 361, a second mark 46 is provided for detecting the above-described specified phase by the imaging device 628. This second mark 46 is provided on the outer peripheral surface of the flange portion 363 at a position on the extension line in the radial direction in which the above-described first marks 45 are arranged. In this case, the imaging device 628 also functions as a detection means for detecting a predetermined phase by the second mark 46.

[0042] The second mark 46 is colored differently from the surface color of the outer peripheral portion of the flange portion 363. Also in this case, the second mark 46 may be a color distinguishable from the surface color of the outer peripheral portion of the flange portion 363 by the imaging device 628 (for example, the same relationship as the relationship between the first mark 45 and the surrounding color).

[0043] The flange portion 363 is circular with a uniform outer diameter in the circumferential direction. And when the winch drum 361 is rotating, a state in which the second mark 46 is located at the center in the diameter direction of the flange portion 363 is defined as a predetermined phase. The monitoring processing unit 611 can recognize that it is in a predetermined phase when the second mark 46 located at the center of the flange portion 363 is detected from the captured image of the imaging device 628.

[0044] Further, a cover 367 that covers the outer peripheral surface is attached to the flange portion 363 of the winch drum 361 to avoid contact with the outside. The cover 367 is fixedly installed on the side of the crane 1 with respect to the rotating flange portion 363. An opening 368 is formed in the cover 367 to expose the second mark 46 to the outside when the second mark 46 reaches the position indicating the aforementioned predetermined phase. The opening 368 is a notch that opens slightly larger than the second mark 46 and does not interfere with the imaging of the second mark 46 by the imaging device 628 at the predetermined phase. It is preferable that the second mark 46 has a color different from the surface color of the cover 367 (for example, the same relationship as the relationship between the first mark 45 and the surrounding color).

[0045] Note that the other flange portion 364 may be formed in a shape in which a certain shape is periodically repeated (for example, a substantially polygonal shape, a substantially gear shape, etc.) to brake the winch drum 361, and the second mark 46 may be provided on this flange portion 364.

[0046] Also, it is preferable to set the aforementioned predetermined phase within the range of the parallel portion 321 of the hoisting rope 32 wound around the winch drum 361. FIG. 6 is an explanatory diagram showing the range of the parallel portion 321 and the intersecting portion 322 when the hoisting rope 32 wound around the winch drum 361 is viewed from the axial direction. As shown in the figure, the hoisting rope 32 wound around the winch drum 361 is configured to be alternately repeated at a predetermined ratio by the parallel portion 321 and the intersecting portion 322 every half turn.

[0047] This parallel portion 321 indicates a section where the outer diameter of the hoisting rope 32 wound around the winch drum 361 is constant, and the intersecting portion 322 indicates a section where the outer diameter changes. The intersecting portion 322 corresponds to "a first region where the wire rope (hoisting rope 32) wound around the winch drum (361) is inclined with respect to the axial direction of the winch drum (361) according to the rotation phase of the winch drum (361)". The above-mentioned parallel portion 321 corresponds to "a second region where the wire rope (hoisting rope 32) wound around the winch drum (361) is closer to perpendicular than the first region (intersection portion 322) with respect to the axial direction of the winch drum (361)".

[0048] The hoisting rope 32 is wound around the outer periphery of the winding cylinder 362 of the winch drum 361, drawing a gentle helix for each layer. Since the parallel portion 321 is wound in a state of being fitted into a groove-shaped recess along the helix of the helical hoisting rope 32 of the inner layer, the outer diameter of the outer periphery is stable and constant within that section. On the other hand, the two layers in contact with the inside and outside of the hoisting rope 32 have the same winding rotation direction but different traveling directions. For this reason, a section where the hoisting rope 32 of the lower layer is overcome by coming off the spiral groove of the inner layer occurs twice per winding. This is the intersection portion 322, and in that section, the outer diameter of the hoisting rope 32 increases and decreases. As shown in FIG. 6, the parallel portion 321 and the intersection portion 322 occur twice per winding, each time with the same phase interval.

[0049] As described above, it is preferable that the first mark 45 is arranged so as to be more reliably shielded so as not to be imaged by the hoisting rope 32 of the corresponding layer. Therefore, by setting the predetermined phase within the range of the parallel portion 321, the target position for providing the first mark 45 can be made within a range of a certain diameter from the center of the winch drum 361, the target position is easy to determine, and it becomes easy to form the first mark 45 in an appropriately shielded arrangement. On the other hand, since the intersection portion 322 does not become constant from the center of the winch drum 361, it may be necessary to wind the hoisting rope 32 and actually measure to determine the position where the first mark 45 is provided. Furthermore, when a tolerance is set for the rope diameter of the hoisting rope 32, it is difficult to accurately obtain the locus of the intersection portion 322, and there is also a problem that it is difficult to arrange the first mark 45 suitably.

[0050] Therefore, the predetermined phase described above is set within the range of the parallel portion 321. Also, there are two parallel portions 321. In the case of the first row a, since the row slides horizontally by half of the rope diameter of the winding rope 32 at the crossing portion 322, if the range of the parallel portion 321 before entering the crossing portion 322 is set to a predetermined phase, imaging is performed in a state where there is no clearance with respect to the flange portions 363 and 364, which is more preferable. In FIG. 6, the symbol S is the phase at which the winding of the winding rope 32 of the first row a of the first layer starts to be wound around the winch drum 361, and the winding rope 32 is wound in the direction of the arrow Y with respect to the phase S (that is, the winch drum 361 rotates in the direction opposite to the arrow Y). In the case where it is assumed that the first row a hides the first mark 45, if the range of the parallel portion 321 immediately downstream of the phase S among the two parallel portions 321 is set to a predetermined phase, there is no clearance with respect to the flange portions 363 and 364, which is more preferable.

[0051] [Monitoring Process of Winch Drum] The monitoring process by the monitoring processing unit 611 of the controller 61 will be described. The monitoring processing unit 611 performs a monitoring process of obtaining the number of layers of the winding rope 32 wound around the winch drum 361 based on the captured image of the imaging device 628. FIG. 7 is a flowchart of the monitoring process by the monitoring processing unit 611. Based on this, the monitoring process will be described in detail.

[0052] When the winch drum 361 rotates (step S1), the monitoring processing unit 611 captures an image of the winch drum 361 by the imaging device 628 (step S3), and detects the second mark 46 from the captured image through the image processing device 629 (step S5). Since the second mark 46 is exposed from the opening 368 of the cover 367 only when the winch drum 361 is in a predetermined phase, the detection of the second mark 46 indicates that it is in a specified phase. Also, since the second mark 46 has a different color from the outer peripheral surface of the flange portion 363, the image processing device 629 can easily detect the second mark 46 by performing a process of extracting the color of the second mark 46 from the captured image.

[0053] When the monitoring processing unit 611 detects the second mark 46, it executes the detection of the first mark 45 from the captured image at that time (step S7). Since the color of the first mark 45 is different from the inner surfaces of the flange portions 363 and 364, the image processing device 629 can easily detect the first mark 45 by performing a process of extracting the color of the first mark 45 from within the captured image. Thereby, the monitoring processing unit 611 functions as a specifying unit.

[0054] At a predetermined phase, all the first marks 45 are arranged so as to be within the imaging range by the imaging device 628. And the number of all the first marks 45 is known. The monitoring processing unit 611 counts the number of first marks 45 detected from the captured image at the predetermined phase and compares it with the total number of the first marks 45. Then, it derives the number of layers on which the current winding rope 32 is wound based on the difference between the detected number and the total number of the first marks 45 (step S9).

[0055] When the first mark 45 corresponding to the first layer is not provided, the number obtained by adding 1 to the difference between the detected number and the total number of the first marks 45 is the number of layers on which the current winding rope 32 is wound (for the number of layers on which the winding rope 32 is wound up to the last row, it is the difference between the detected number and the total number). Also, table data showing the correspondence between the detected number of the first marks 45 and the number of layers on which the current winding rope 32 is wound may be prepared in advance, and when the detected number of the first marks 45 is obtained, the number of layers on which the current winding rope 32 is wound may be derived by referring to the table data.

[0056] FIG. 8 is an example of a display of a status screen G that displays operation information such as various setting values and detected values in the crane 1 on the display device 622. The monitoring processing unit 611 executes display control to display the derived number of layers of the current winding rope 32 within the frame W in the status screen G on the display device 622 (step S11), and ends the monitoring process. Note that the monitoring processing unit 611 may perform control to notify, by voice, the number of layers of the current hoisting rope 32 using an audio output device such as a speaker provided in the cab 33, instead of or in addition to the display control for displaying the number of layers of the current hoisting rope 32 by the display device 622.

[0057] In addition, the monitoring processing unit 611 may perform notification processing to notify not only the display of the number of layers of the current hoisting rope 32 but also when the number of layers of the hoisting rope 32 reaches or approaches 1. For example, when the number of layers of the current hoisting rope 32 is reduced to 1 by the monitoring process, for example, on the status screen G of FIG. 8, a display such as an icon N1 that notifies that the number of layers of the hoisting rope 32 has become 1 may be performed to notify the operator. Also, control for notification by voice may be performed. When notifying when the number of layers of the hoisting rope 32 approaches 1, stepwise notification may be performed depending on whether the number of layers of the current hoisting rope 32 is 2 or 1. In that case, for example, on the status screen G of FIG. 8, displays such as the icon N1 are performed using a color (for example, yellow) that notifies that the number of layers of the hoisting rope 32 is 2 and a color (for example, red) that notifies that the number of layers of the hoisting rope 32 is 1 to notify the operator. Also, when notifying by voice, control for gradually changing the tone may be performed.

[0058] [Technical Effects of the Embodiment of the Invention] As described above, the winch drum monitoring device that monitors the state of the winch drum 361 of the crane 1 has the first mark 45 provided on the inner surfaces of the flange portions 363 and 364 of the winch drum 361, and the monitoring processing unit 611 determines the number of layers of the hoisting rope 32 by detecting the first mark 45 with the imaging device 628. Since the above monitoring device targets the first mark 45 having a unique appearance for imaging, even when disturbance factors such as dirt or oil adhesion on the hoisting rope 32 occur, the first mark 45 can be clearly detected, and it is possible to accurately and stably detect the number of layers of the hoisting rope 32. In particular, since the first mark 45 has a color different from the surface color of the flange portions 363 and 364, the first mark 45 can be detected more accurately without being buried in the surrounding image, and the number of layers of the winding rope 32 can be detected accurately.

[0059] Further, since each first mark 45 corresponds to a plurality of layers of the winding rope 32 wound and laminated on the winch drum 361, the number of layers of the winding rope 32 can be obtained from the number of detected first marks 45, and the detection accuracy of the number of layers of the winding rope 32 can be further improved.

[0060] Further, on the winch drum 361, the first marks 45 corresponding to the inner layers of the winding rope 32 to the first marks 45 corresponding to the outer layers are alternately arranged on the flange portions 363 and 364 on both sides in order. Therefore, it is possible to appropriately detect the number of layers of the winding rope 32 with respect to the winch drum 361 that alternately winds up on one flange portion 363 side and winds up on the other flange portion 364 side.

[0061] Further, each first mark 45 is provided on the inner side in the radial direction of the winch drum 361 rather than the center portion 32c of the rope diameter of the winding rope 32 of the corresponding layer. For this reason, when the winding rope 32 of the corresponding layer is wound, the first mark 45 is located inside the maximum portion of the rope diameter of the winding rope 32, and the first mark 45 can be effectively hidden. Therefore, the presence or absence of the first mark 45 can be clearly detected, and the detection accuracy of the number of layers of the winding rope 32 can be further improved.

[0062] Further, since the monitoring device functions as a detection means for the imaging device 628 to detect the rotation phase of the winch drum 361 by the second mark 46 and has a phase detection means, the number of layers of the winding rope 32 can be obtained using the captured image at a predetermined phase. For this reason, it is possible to reduce the influence of the state change of the wound winding rope 32 due to the phase difference and to detect the number of layers of the winding rope 32 more accurately. In addition, since the monitoring processing unit 611 performs the process of identifying the number of layers based on the captured image at the time of detecting the predetermined phase, it is not necessary to always perform the process, and it is possible to reduce the processing load.

[0063] In addition, in the winch drum 361, as the predetermined phase is set within the range of the parallel portion 321 of the hoisting rope 32, each first mark 45 is provided within the range of the parallel portion 321 of the hoisting rope 32. Therefore, the target position for providing the first mark 45 can be within a range of a certain diameter from the center of the winch drum 361, the target position is easy to determine, and it becomes easy to form the first mark 45 in an arrangement that is properly shielded by the hoisting rope 32. In addition, since the first mark 45 is arranged to avoid the crossing portion 322, it is not necessary to determine the arrangement of the first mark 45 by calculating the locus of the crossing portion 322 that is not constant from the center of the winch drum 361 or by actually measuring the hoisting rope 32, and it becomes possible to easily form each first mark 45 at an appropriate position. In particular, when a tolerance is set for the rope diameter of the hoisting rope 32 used, it is extremely difficult to accurately obtain the locus of the crossing portion 322, but such a problem can be avoided and it becomes possible to easily form each first mark 45 at an appropriate position.

[0064] In addition, since the first mark 45 is provided inside the depression 45a formed on the inner surfaces of the flange portions 363, 364, it is possible to suppress the sliding contact with the hoisting rope 32, suppress the blurring of the appearance and color of the first mark 45, and maintain good detection.

[0065] In addition, since the winch drum 361 is provided with the first mark 45 for identifying the number of layers of the hoisting rope 32 wound around the winding cylinder 362 on the inner surfaces of the flange portions 363, 364, it is possible to accurately detect the number of layers of the hoisting rope 32 based on the first mark 45.

[0066] [Another Aspect of the First Mark] FIGS. 9(A) and 9(B) show other examples of the first mark. Hereinafter, each first mark will be described. The example shown in Fig. 9(A) shows the case where one first mark 45A is provided regardless of the number of layers of the hoisting rope 32. The first mark 45A is a long single mark along the radial direction of the winch drum 361 on the inner surface of the flange portion 363. The first mark 45A is formed in a color different from that of the inner surface of the flange portion 363, similar to the case of the first mark 45. Note that the first mark 45A only needs to intersect all the hoisting ropes 32 of each layer wound around the winch drum 361 when viewed from the axial direction, and within that range, it may be provided with a slight inclination with respect to the radial direction of the winch drum 361.

[0067] Also, the second mark 46 indicating a predetermined phase is preferably provided on the outer peripheral surface of the flange portion 363 in an arrangement on the same extension line in the radial direction as the first mark 45A.

[0068] In the case of this first mark 45A, it is hidden by the hoisting rope 32 in order from the end side on the radially inner side according to the number of layers of the hoisting rope 32. Therefore, it is possible to obtain the current number of layers of the hoisting rope 32 from the length or area of the first mark 45 imaged by the imaging device 628.

[0069] The example shown in Fig. 9(B) shows the case where each first mark 45B corresponding to each layer of the hoisting rope 32 is in an arc shape along the hoisting rope 32 of each layer. In this case, the plurality of first marks 45B are in an arc shape with an equal phase range. Also, the second mark 46B is preferably in an arc shape with the same phase range as the first mark 45B. In this case, since the predetermined phase range for imaging the first mark 45B can be widely expanded, it is possible to obtain the number of layers multiple times during each rotation of the winch drum 361, and it becomes possible to obtain the number of layers of the hoisting rope 32 with higher accuracy.

[0070] [Example of obtaining the number of layers based on the first mark hidden by the hoisting rope in the last row] In the above-described embodiment, an example where the first row a hides the first mark 45 is shown. However, as shown in Fig. 10, it is also possible to obtain the number of layers based on the first mark 45 hidden by the last row b in each layer. In this case, in the even layers of the hoisting rope 32, the last row b is on the other flange portion 364 side (the left flange portion in the example of FIG. 10), and in the odd layers, it is on the one flange portion 363 side (the right flange portion in the example of FIG. 10). Therefore, the first marks 452 and 454 corresponding to the last row b in the even layers are provided on the flange portion 364, and the first marks 453 and 455 corresponding to the last row b in the odd layers are provided on the flange portion 363. Also, it is preferable to provide the first mark 451 corresponding to the last row b in the first layer on the flange portion 363 without omission.

[0071] Also, when it is assumed that the last row b hides the first mark 45, the predetermined phase to be monitored by the monitoring processing unit 611 is preferably within the range of the parallel portion 321 in FIG. 6 described above even in the case of the last row b. However, in the case of the last row b, since the row contacts the flange portion after sliding horizontally by half of the rope diameter of the hoisting rope 32, if the range of the parallel portion 321 after entering the crossing portion 322 is set as the predetermined phase, imaging can be performed without a gap with respect to the flange portions 363 and 364, which is more preferable. For example, in FIG. 6, if the range of the parallel portion 321 that is not immediately downstream of the phase S among the two parallel portions 321 is set as the predetermined phase, there will be no gap with respect to the flange portions 363 and 364, which is more preferable.

[0072] Also, when it is assumed that the first mark 451 corresponding to the first layer is provided on the premise that the last row b hides the first mark 45, the number obtained by adding 1 to the difference in the number of detections with respect to the total number of the first marks 45 is the number of layers of the current hoisting rope 32 that is wound (for the number of layers of the hoisting rope 32 wound up to the last row, it is the difference in the number of detections with respect to the total number). Also in this case, the number of layers of the current hoisting rope 32 that is wound may be derived by referring to the table data.

[0073] [Others] The details shown in the embodiments of the above invention can be appropriately changed without departing from the spirit of the invention. For example, when a plurality of first marks 45 are provided corresponding to each layer of the hoisting rope 32, they may have different colors for each first mark 45 of each layer. By identifying the color of the first mark 45 detected by imaging, it becomes possible to easily determine the number of layers of the hoisting rope 32. Further, the first mark 45 may use a simple two-dimensional code such as that used for an AR marker.

[0074] In addition, in the above monitoring device, the imaging device 628 is illustrated as the detection means for detecting the rotational phase of the winch drum 361, but a configuration may be adopted in which a dedicated sensor or the like capable of detecting the rotational phase of the winch drum 361 is separately provided.

[0075] In the above embodiment, a monitoring device for the winch drum 361 of the hoisting winch 36 is illustrated, but a monitoring device having the same configuration may also be provided for the winch drum of the luffing winch 42. In the above embodiment, an example of providing a monitoring device for the winch drum of a crawler crane is shown. However, the present invention is applicable not only to crawler cranes but also to other mobile cranes such as cranes with tower attachments, wheel cranes, truck cranes, etc., and also to all cranes having winch drums such as harbor cranes, overhead cranes, jib cranes, gantry cranes, unloaders, fixed cranes, etc. Moreover, the present invention is applicable not only to cranes equipped with a load hook but also to cranes that suspend attachments such as magnets and earth drill buckets.

[0076] Further, the first mark does not necessarily need to be provided for each consecutive layer. For example, the first mark may be provided at uniform intervals such as every two layers, every three layers, etc. In that case, when the specified number of layers is displayed on, for example, the above-mentioned status screen G, etc., it may be displayed as grouped numbers of layers such as "layers 1 - 2", "layers 3 - 4".

Explanation of Reference Numerals

[0077] 1 Crane 32 Hoisting Rope (Wire Rope) 32c Central part 36 Hoisting winch 37 Undulating rope (wire rope) 42 Undulating winch 45, 452, 453, 454, 455, 45A, 45B First mark 45a Depression 46, 46B Second mark 60 Control device 61 Controller 321 Parallel part 322 Intersection part 361 Winch drum 362 Winding cylinder (winding part) 363, 364 Flange part 367 Cover 368 Opening 611 Monitoring processing unit 622 Display device 628 Imaging device (imaging part) 629 Image processing device G Status screen N1 Icon

Claims

1. A monitoring device for a winch drum that monitors the state of the winch drum, comprising an imaging unit that images the winch drum, wherein the winch drum has a winding portion around which a wire rope is wound and flange portions provided on both sides of the winding portion, a first mark is provided on the inner surface of the flange portion, a specifying unit that specifies the number of layers in which the wire rope is wound around the winding portion by detecting the first mark in the captured image captured by the imaging unit, and detection means for detecting the rotational phase of the winch drum, wherein the specifying unit specifies the number of layers based on the captured image when a specific rotational phase is detected by the detection means A monitoring device for a winch drum.

2. Based on the rotational phase of the winch drum, there are a first region where the wire rope wound around the winch drum is inclined with respect to the axial direction of the winch drum and a second region where the wire rope wound around the winch drum is closer to being perpendicular to the axial direction of the winch drum than the first region, and the specific rotational phase is included in the second region The monitoring device for a winch drum according to Claim 1.

3. A monitoring device for a winch drum that monitors the state of the winch drum, comprising an imaging unit that images the winch drum, wherein the winch drum has a winding portion around which a wire rope is wound and flange portions provided on both sides of the winding portion, a first mark is provided on the inner surface of the flange portion, having a specifying unit that specifies the number of layers in which the wire rope is wound around the winding portion by detecting the first mark in the captured image captured by the imaging unit, wherein the first mark is a plurality of marks corresponding to a plurality of layers of the wire rope wound in layers on the winch drum, and the first mark is provided on the inner side in the radial direction of the winch drum than the center portion of the wire rope diameter of the corresponding layer A monitoring device for a winch drum.

4. The first mark includes an inner layer mark provided on one of the flange portions and corresponding to a predetermined winding layer of the wire rope, and an outer layer mark provided on the other of the flange portions and corresponding to a winding layer outside the predetermined winding layer The monitoring device for a winch drum according to Claim 3.

5. The first mark has a color different from the surface color of the flange portion The monitoring device for a winch drum according to any one of Claims 1 to 4.

6. The first mark is provided inside a depression formed on the inner surface of the flange portion. The winch drum monitoring device according to any one of claims 1 to 5. **Claim 7** The first mark has an arcuate portion along the circumferential direction of the winch drum. The winch drum monitoring device according to any one of claims 1 to 6. **Claim 8** A winch drum includes a winding portion around which a wire rope is wound, and flange portions provided on both sides of the winding portion. On the inner surface of the flange portion, a first mark for specifying the number of layers of the wire rope wound around the winding portion is provided. The first mark is a plurality of marks corresponding to a plurality of layers of the wire rope laminated and wound around the winch drum. The first mark is provided on the inner side in the radial direction of the winch drum from the center of the wire rope diameter of the corresponding layer. Winch drum.

Images