Wire ropes and cranes

Abstract

This addresses requirements regarding the attachment position of wire ropes to objects being lifted. [Solution] A wire rope 40 having a main rope portion 41 whose base end can be connected to a crane hook F, and a first engaging portion 43 provided at the tip of the main rope portion 41 opposite to the base end, wherein a second engaging portion 44 that can engage with the first engaging portion 43 is provided at a position between the tip and base end of the main rope portion 41 or at the base end, and a covering portion 45 that covers at least a portion of the main rope portion 41 between the tip and base end, the wire rope 40 can be properly secured to either the upper or lower side of the object to be lifted and lifted.

Description

Technical Field

[0001] The present invention relates to a wire rope and a crane.

Background Art

[0002] In the case of a crane with a boom attachment that can be removed from the crane body, during transportation and assembly, the wire rope is connected to the boom attachment in a supine or prone state and lifted (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] When locking a wire rope to a boom attachment (see FIG. 3) loaded on a transport vehicle or a large boom attachment to perform hanging, the appropriate position for locking the wire rope varies depending on the situation, and the conventional wire rope could not sufficiently respond to changes in the locking position.

[0005] <� An object of the present invention is to make it easier to respond to the requirements for the locking position of the wire rope with respect to the object to be hung.

Means for Solving the Problems

[0006] <� One aspect of the present invention is <� a main rope portion whose base end portion can be connected to a hook of a crane, <� a first engaging portion provided at a tip end portion on the opposite side of the base end portion of the main rope portion, <� a wire rope having <� A second engaging portion, which can engage with the first engaging portion, is provided in the main rope portion at a position between the tip and base end, or at the base end. This wire rope has a covering portion that covers at least a portion of the main rope section between the tip and the base.

[0007] Furthermore, other embodiments of the present invention include: A crane having a crane body and a boom attachment that can be raised and lowered and attached to the crane body, When the boom attachment is positioned with one of its four longitudinal surfaces facing upwards, A first engaging portion is provided on the side of the boom attachment facing upwards, which is capable of securing a wire rope. This crane is provided with a second engagement portion on the lower side of the boom attachment, which is capable of securing the wire rope. [Effects of the Invention]

[0008] According to the present invention, it becomes possible to more easily accommodate requirements regarding the attachment position of the wire rope to the object being lifted. [Brief explanation of the drawing]

[0009] [Figure 1] This is a perspective view of a crane. [Figure 2] This is a side view of the intermediate boom, which is lying face down on the ground. [Figure 3] This is a side view of the intermediate boom in the same position as in Figure 2, loaded onto a transport vehicle. [Figure 4] This is an enlarged view of the second locking projection, seen from the same direction as in Figures 2 and 3. [Figure 5] This is an overall diagram of the wire rope. [Figure 6] This is an overall view of the wire rope as seen from the bottom of the page in Figure 5. [Figure 7] This is a side view of an intermediate boom showing another example of rigging, different from Figure 2. [Figure 8] It is a side view of an intermediate boom showing yet another example of a ball suspension different from that of FIG. 2. [Figure 9] It is an overall view of another example of a wire rope as seen from the same direction as the wire rope in FIG. 6. [Figure 10] It is an overall view of yet another example of a wire rope as seen from the same direction as the wire rope in FIG. 5.

Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the scope of the present invention is not limited to the embodiments disclosed below. Since the drawings are provided for illustrative purposes only, the scope of the present invention is not limited to the illustrations in the drawings.

[0011] [Crane] FIG. 1 is a perspective view of a crane 20. A crawler crane is illustrated as the crane 20. Regarding the description of the entire crane 20 below, the forward direction of the crane 20 (regardless of the direction in which the upper slewing body 22 described later faces, the predetermined forward direction of the lower traveling body 21) is "front", the backward direction is "rear", the left side when facing forward from the crane 20 is "left", and the right side when facing forward is "right".

[0012] In FIG. 1, the crane 20 includes a self-propelled crawler-type lower traveling body 21, an upper slewing body 22 rotatably mounted on the lower traveling body 21, and a boom 23 as a boom attachment attached to the front side of the upper slewing body 22 so as to be able to rise and fall.

[0013] The lower traveling body 21 includes a truck frame 211, drive wheels 212 and idler wheels 213 provided on both the left and right sides of the truck frame 211, and crawler belts 214 wound around the drive wheels 212 and the idler wheels 213. The left and right drive wheels 212 are rotationally driven by traveling hydraulic motors (not shown) respectively.

[0014] The upper slewing body 22 has a slewing frame 221 extending in the front and rear directions. The lower end of the boom 23 is connected and supported on the front side of the slewing frame 221. The slewing frame 221 functions as a crane body that supports the boom 23. Also, the lower end of the gantry 25 is connected and supported on the rear side of the boom support position on the slewing frame 221. The upper slewing body 22 is also slewing-driven about a vertical axis with respect to the lower traveling body 21 by a slewing hydraulic motor (not shown).

[0015] A counterweight 222 for balancing the weights of the boom 23 and the suspended load is disposed at the rear of the slewing frame 221. A boom hoisting winch 245 is disposed immediately in front of the counterweight 222, and a main winch 241 and a supplementary winch 242 are disposed further in front of it. Also, a cab 225 for an operator to board is arranged on the right front side of the slewing frame 221.

[0016] The boom 23 is attached to the slewing frame 221 of the upper slewing body 22 so as to be able to rise and fall. The boom 23 includes a lower boom 231, an intermediate boom 232, and an upper boom 233.

[0017] Sheave brackets 234 and 235 are provided at the upper end of the upper boom 233. A guide sheave 236 is rotatably attached to the sheave bracket 234, and a point sheave 237 is rotatably attached to the sheave bracket 235. The guide sheave 236 and the point sheave 237 are for winding the main winch rope 243.

[0018] The main winch 241 winds and unwinds the main winch rope 243 by a main winch hydraulic motor (not shown) to raise and lower the main hook 244 and the suspended load. The supplementary winch 242 winds and unwinds a supplementary winch rope (not shown) to which a supplementary hook (not shown) is attached by a supplementary winch hydraulic motor (not shown).

[0019] The gantry 25 is rotatably attached at its lower end to a bracket (not shown) of the slewing frame 221 by pin connection, and its upper end is rotatable in the front-rear direction. The upper end of the gantry 25 is provided with a lower boom spreader 251 having multiple sheaves.

[0020] On the other hand, the boom luffing rope 26 is composed of a boom winding rope 261 and a boom pendant rope 262. The upper end of the boom pendant rope 262 is connected to the upper end of the upper boom 233, and the lower end of the boom pendant rope 262 is provided with a boom upper spreader 252 having multiple sheaves. The boom winding rope 261 has one end wound around the boom luffing winch 245, and the other end wound around the sheaves of the upper boom spreader 252 and the lower boom spreader 251.

[0021] The boom luffing winch 245 uses a luffing hydraulic motor (not shown) to wind and unwind the boom winding rope 261, adjusting the luffing angle of the boom 23 relative to the slewing frame 221.

[0022] The crane 20 described above can be disassembled into multiple components for transport. As one of its components, the boom 23 is detachable from the upper slewing body 22, and for transport, the boom 23 can be further disassembled into a lower boom 231, an intermediate boom 232, and an upper boom 233.

[0023] During disassembly, the boom 23 is placed in a prone position, tilted forward relative to the upper slewing body 22, and one end at the base is separated from the upper slewing body 22, disassembling it into the lower boom 231, intermediate boom 232, and upper boom 233. During assembly, the boom 23 is connected, with the lower boom 231, intermediate boom 232, and upper boom 233 connected, placed on the ground in a prone position, and one end connected to the upper slewing body 22. In the context of boom attachments, "prone position" refers to a state where the front (ventral side) of the boom attachment is facing downwards when it is raised and in use, while "supine position" refers to a state where the rear (backside) of the boom attachment is facing downwards when it is raised and in use. The boom 23 is roughly rectangular in shape with four faces along its longitudinal direction. During load lifting operations (as shown in Figure 1), the front-facing face (ventral face) is positioned downwards, and the rear-facing face (back face) is positioned upwards, allowing for assembly and disassembly. In the following description, unless otherwise specified, when referring to boom 23 and the lower boom 231, intermediate boom 232, and upper boom 233 that constitute boom 23, "down" or "up" refers to the "down" side or "up" side when the ventral side is facing downwards.

[0024] Figure 2 is a side view of the intermediate boom 232 lying prone on the ground, and Figure 3 is a side view of the intermediate boom 232 in the same position as in Figure 2, loaded onto a transport vehicle T. Note that in Figures 2 and 3, the length of the intermediate boom 232 is shown to be shorter for convenience.

[0025] The intermediate boom 232 has four main members 31 along the longitudinal direction of the boom 23 and auxiliary members 32 positioned between each of the main members 31. The four main members 31 are positioned at the four corners of a rectangle when viewed from the longitudinal direction of the boom 23, and each auxiliary member 32 is suspended diagonally between two adjacent main members 31, with both ends integrally connected to each main member 31.

[0026] The intermediate boom 232, like the boom 23, is roughly rectangular in shape with four faces along its longitudinal direction, and is placed on the ground or loaded onto a transport vehicle T with its underside facing downwards and its back facing upwards. During the assembly, disassembly, and transportation of the crane 20, the work is carried out by lifting it onto the hook F of another crane via the wire rope 40, as shown in Figures 2 and 3.

[0027] Therefore, on the lower surface of the two main members 31 that are on the rear side (upper side) of the intermediate boom 232, there are two first locking projections 33 at the midpoint in the longitudinal direction, which are downwardly convex and serve as first engaging parts for locking the wire rope 40. Furthermore, on the upper surfaces of the two main members 31 that make up the ventral side (lower side) of the intermediate boom 232, there are two second locking projections 34 at the midpoint in the longitudinal direction, which are convex upwards and serve as second engaging parts for locking the wire rope 40.

[0028] The first locking projection 33 has a round rod-shaped shaft portion 331 that hangs downward from the lower surface of the main member 31 on the back side, and an extended portion 332 that protrudes in a direction that spreads out around the shaft portion 331 at the lower end of the shaft portion 331. The first locking projection 33 is provided in a state where it is integrally fixed to the lower surface of the main member 31 on the rear side. The wire rope 40 is secured by wrapping it around the shaft portion 331 of the first locking projection 33, and the expansion portion 332 prevents it from falling off the shaft portion 331.

[0029] Figure 4 is an enlarged view of the second locking projection 34, viewed from the same direction as in Figures 2 and 3. The second locking projection 34 includes a locking plate 341 with a locking hole through which a hook passes, a base portion 342 on which the locking plate 341 is fixedly erected, and a substantially U-shaped connecting member 343 that straddles the main member 31 from below.

[0030] The locking plate 341 has a locking hole 341a that penetrates the main member 31 in a direction perpendicular to the longitudinal direction. The base portion 342 has a bottom portion 342a that is placed on the upper surface of the main member 31, and side portions 342b that rise from both sides of the bottom portion 342a, and the bottom portion 342a and the side portions 342b on both sides are joined to the lower outer edge of the locking plate 341.

[0031] The connecting member 343 has male threads formed on both of its bifurcated upper ends, and is inserted into through holes provided on the bottom surface of the base portion 342. The bifurcated upper ends of the connecting member 343 are inserted into the through holes of the base portion 342 from below, straddling the main member 31, and each upper end is fastened to the base portion 342 with nuts. The second locking projection 34 is fixed to the main member 31 by fastening a nut, and can be removed from the main member 31 by loosening the nut, as described above.

[0032] The first locking projection 33 may also be configured to be removable from the main member 31. The second locking projection 34 may be fixedly attached to the main member 31 in a way that prevents removal. If the first locking projection 33 and the second locking projection 34 are provided facing the inner region surrounded by the four main members 31, as described above, they do not need to be detachably mounted from the main members 31. Conversely, if the first locking projection 33 and the second locking projection 34 are provided facing outwards from the inner region, it is preferable that they be detachably mounted from the main members 31. When using the crane 20, the first locking projection 33 or the second locking projection 34 is removed to prevent the various wires of the crane 20 from accidentally getting caught on the first locking projection 33 or the second locking projection 34.

[0033] While the intermediate boom 232 of boom 23 has been described, the lower boom 231 and upper boom 233 also share the same structure as the intermediate boom 232. Specifically, both the lower boom 231 and the upper boom 233 have four main members and auxiliary members. The main members of the lower boom 231 are bundled together as the distance between adjacent main members decreases as they go down, and the distance between adjacent main members of the upper boom 233 is also bundled together as they go up. Furthermore, the lower boom 231 and upper boom 233 are also disassembled and reassembled with their undersides facing downwards. Furthermore, the two upper main members are provided with first locking projections 33, and the two lower main members are provided with second locking projections 34.

[0034] [Wire rope] Figure 5 is an overall view of the wire rope 40, and Figure 6 is an overall view of the wire rope 40 as seen from below the page of Figure 5. The wire rope 40 has four main rope sections 41 whose base ends can be connected to the hook F of a crane used for assembly or disassembly work, a binding ring 42 (not shown in Figure 6) which serves as a hook engagement part that bundles the base ends of the four main rope sections 41 and connects them to the hook F, a first engagement part 43 provided at the tip of the main rope section 41 opposite to the base end, a second engagement part 44 (not shown in Figure 5) provided at a position between the tip and base end of the main rope section 41 and capable of engaging with the first engagement part 43, and a covering part 45 that covers at least a portion of the main rope section 41 between the tip and base end. In this embodiment, the example shows that the covering portion 45 covers an area including the tip of the main rope portion 41, but covering the tip is not essential.

[0035] The main rope section 41 is a rope made of steel cable, which is made by twisting together multiple strands of metal wire such as steel. The main rope section 41 may have a core wire on the inside, or it may be made by further twisting and bundling multiple steel cables together.

[0036] The base end of the main rope section 41 (the left-hand end in Figures 5 and 6) is provided with a connecting portion 411 for the binding ring 42. The connecting portion 411 is constructed by folding back the end of the rope, which is made of steel cable and constitutes the main rope section 41, to form an annular portion, and then crimping the folded end with a metal sleeve. The connecting portion 411 is crimped with a metal sleeve while an endless annular metal binding ring 42 is inserted through it. As a result, the connecting portion 411 is connected to the binding ring 42 in a way that makes it impossible to remove.

[0037] The connecting portion 411 may be made of a hook and be detachable from the fastening ring 42. However, it is preferable to use a hook with a latch to prevent accidental detachment. Furthermore, the connecting portion 411 may be widened so that it can be directly connected to the crane hook F without using the binding ring 42. In this case, each main rope portion 41 functions as a wire rope. Also in this case, the connecting portion 411 only needs to have a structure that can be connected to the hook F, and may be annular or hook-shaped. If it is hook-shaped, it is preferable to have a hook with a latch.

[0038] A first engaging portion 43 is provided at the tip of the main rope portion 41 (the right-hand end in Figures 5 and 6). The first engaging portion 43 consists of a hook that can be connected to a ring-shaped second engaging portion 44, which will be described later. It is preferable that the first engaging portion 43 and the second engaging portion 44 can be connected and disconnected manually. Therefore, the first engaging portion 43 may be ring-shaped and the second engaging portion 44 may be a hook. In either case, it is preferable that the hook is a hook with a latch.

[0039] As shown in Figure 6, a second engagement portion 44 is provided between the tip and base of the main rope portion 41 via a branch rope portion 441. The second engagement portion 44 has an endless ring shape. Multiple second engagement portions 44 are provided on a single main rope portion 41, arranged in the longitudinal direction of the main rope portion 41. In this embodiment, three second engagement portions 44 are provided on a single main rope portion 41. The number of second engagement portions 44 may be one, two, or four or more. Each second engaging portion 44 may be located on the other end side of the main rope portion 41, and in this embodiment, all second engaging portions 44 are provided on the base end side (connecting portion 411 side) of the longitudinal middle portion of the main rope portion 41. However, the arrangement of each second engaging portion 44 is illustrative, and they may be arranged on the tip side or base end side of the above arrangement.

[0040] Each branch rope section 441 is connected at one end so as to branch off from the main rope section 41, and at the other end is connected to the second engagement section 44. The lengths of each branch rope section 441 are equal. Furthermore, the length of each branch rope section 441 is shorter than the distance from the connection point (branching point) of the branch rope section 441 that is closest to the tip (first engagement section 43) of the three to the tip side (first engagement section 43) of the main rope section 41.

[0041] The covering portion 45 covers a portion of the main rope portion 41, extending from the tip end towards the base end. As mentioned above, the main rope section 41 is made of a steel cable made by twisting steel wires together or a twisted steel cable. Therefore, if the main rope section 41 comes into contact with the crane 20, in particular the boom 23 used for lifting, it will cause damage. To prevent this, a covering section 45 is provided on the main rope section 41. The covering section 45 is also provided to protect the main rope section 41 from damage.

[0042] The covering portion 45 may be made of a softer material than the main rope portion 41, such as resin or rubber, and may be formed as a layered or film-like covering on the surface of the main rope portion 41. Furthermore, the covering portion 45 may be made of a separate component that can be separated from the main rope portion 41. For example, a cylindrical covering portion 45 may be placed over the surface of the main rope portion 41. Alternatively, the covering portion 45 may be attached to the main rope portion 41 by wrapping it with adhesive tape made of the above material.

[0043] Furthermore, the covering portion 45 may be made of a transparent, soft material such as resin or rubber. In that case, the covered main rope portion 41 becomes visible, making it possible to check for damage or deterioration of the main rope portion 41, thus improving maintainability.

[0044] The covering area of ​​the covering portion 45 along the longitudinal direction of the main rope portion 41 preferably includes the tip of the main rope portion 41 and extends from the tip toward the other end. For example, it is preferable to cover an area from the tip of the main rope portion 41 to at least half the length from the base of the branch rope portion 441 of the second engagement portion 44 closest to the base end. Furthermore, the covering portion 45 may cover the area from the tip of the main rope portion 41 to the base of the branch rope portion 441 of the second engaging portion 44, which is the furthest forward of the three ropes. Furthermore, the covering portion 45 may cover the entire length of the main rope portion 41.

[0045] [How wire ropes are used] The usage of the wire rope 40 described above will be explained using Figures 2 and 3 as an example, using the lifting operation of the intermediate boom 232 by rigging during the disassembly and assembly of the crane 20.

[0046] For example, as shown in Figure 2, when the intermediate boom 232 is relatively small or when lifting an intermediate boom 232 that is placed on the ground, it may be possible to perform the work more smoothly by attaching the wire rope 40 to the first locking projections 33 provided on the two main members 31 that are above the second locking projection 34 that is closer to the ground, and connecting the hook F of the work crane to the intermediate boom 232.

[0047] In that case, the binding ring 42 of the wire rope 40 is connected to the hook F, and the first engaging portion 43 of each hanging main rope section 41 is folded upward. Furthermore, the area of ​​the main rope section 41 where the covering portion 45 is provided is wrapped around the shaft portion 331 of the first locking projection 33, and the first engaging portion 43 is connected to the second engaging portion 44.

[0048] In this case, among the multiple second engaging portions 44, the one with an appropriate length for the annular portion formed by the connection of the first engaging portion 43 and the second engaging portion 44 is selected. For example, when the hook F and the intermediate boom 232 are close together or the distance between the two first engaging portions 43 aligned along the main member 31 is not very wide, it is preferable to select the second engaging portion 44 that is closer to the binding ring 42. When the hook F and the intermediate boom 232 are separated or the two first locking projections 33 are separated, it is preferable to select the second engaging portion 44 that is farther from the binding ring 42. Furthermore, since each of the two main members 31 is provided with two first locking projections 33, it is necessary to lock the four main rope sections 41 to their respective first locking projections 33. In this case, it is preferable, in principle, to select the second engagement section 44 that is the same distance from the binding ring 42. This makes it easier to lift the intermediate boom 232 while keeping it horizontal.

[0049] Furthermore, as shown in Figure 3, for example, when the intermediate boom 232 is loaded onto the transport vehicle T, or when the intermediate boom 232 is relatively large, the top of the intermediate boom 232 may be at a high elevation. In such cases, it may be possible to perform the work more smoothly by attaching the wire rope 40 to the second locking projection 34, which is closer to the ground, and connecting the hook F of the work crane to the intermediate boom 232.

[0050] In that case, the binding ring 42 of the wire rope 40 is connected to the hook F, and the first engaging portion 43 of each hanging main rope portion 41 is connected by engaging it with the locking hole 341a of the locking plate 341 of the second locking projection 34. Furthermore, since each of the two main members 31 is provided with two second locking projections 34, the four main rope sections 41 are connected by locking them to their respective second locking projections 34, and the lifting operation of the intermediate boom 232 is performed.

[0051] [Technical Effects of Embodiments of the Invention] The wire rope 40 having the above configuration has a second engaging portion 44 that can engage with the first engaging portion 43 in the middle of the main rope portion 41, and a covering portion 45 between the tip and base ends that covers a part of the main rope portion 41. Therefore, it is possible to change the wire rope attachment position according to the situation for objects to be lifted, such as the boom 23 as a boom attachment and the intermediate boom 232 which is a segment of the boom. For example, it is possible to suitably accommodate situations where there is a need to secure wire ropes to both the upper and lower sides of an object, depending on whether the boom attachment is placed on the ground or in a position above the ground. For example, when connecting a wire rope 40 to the upper side of an intermediate boom 232, the covering portion 45 of the main rope portion 41 can be wrapped around and secured to the first locking projection 33 provided on the upper side of the intermediate boom 232. This prevents damage to the intermediate boom 232, allowing lifting and other operations to be carried out. Furthermore, when connecting the wire rope 40 to the underside of the intermediate boom 232, the first engaging portion 43 at the tip of the main rope portion 41 can be engaged with the second locking projection 34 provided on the underside of the intermediate boom 232. In this case, a portion of the main rope portion 41 extending from the tip towards the base may come into contact with the side surface of the intermediate boom 232. However, the covering portion 45 prevents damage to the intermediate boom 232, allowing lifting and other operations to be carried out.

[0052] Furthermore, since the wire rope 40 has multiple second engagement portions 44 provided along the longitudinal direction of the main rope portion 41, when the main rope portion 41 is folded back and wrapped around to secure it, the total length of the main rope portion 41 after folding can be appropriately selected, making it possible to adjust the length to suit the object being lifted.

[0053] Furthermore, since the wire rope 40 has a second engaging portion 44 attached to the main rope portion 41 via a branch rope portion 441 that branches off from the main rope portion 41, the locking operation can be performed while moving both the first engaging portion 43 and the second engaging portion 44, improving the workability of the locking operation.

[0054] Furthermore, the wire rope 40 is configured such that the length of the branched rope section 441 is shorter than the length of the branched rope section 441 from the branching point to the tip of the main rope section 41. If the branch rope section 441 is too long, the first engaging section 43 and the second engaging section 44 may come into direct contact with the object being lifted and cause damage, or the first engaging section 43 and the second engaging section 44 may break. However, by limiting the length as described above, it is possible to suppress the occurrence of damage and breakage of the first engaging section 43 and the second engaging section 44. Furthermore, if the branch rope section 441 is too long, problems such as entanglement may occur, but by limiting its length as described above, it is possible to suppress entanglement. Furthermore, if the branch rope section 441 is too long, it will be necessary to provide a covering section, similar to the main rope section 41. However, by limiting the length as described above, the need to provide a covering section is reduced. Furthermore, since the length of the branch rope section 441 from the branching point to the tip of the main rope section 41 is longer than the branch rope section 441, when rigging by wrapping the rope, the main rope section 41 will be wrapped around it. However, the covering section 45 covers a portion of the main rope section 41 between the tip and the branch rope section 441, thus suppressing damage and enabling lifting and other operations.

[0055] Furthermore, if the covering portion 45 of the wire rope 40 is made of a separate component that can be separated from the main rope portion 41, then if the covering portion 45 is damaged or deteriorated, only the covering portion 45 can be replaced, making it possible to reuse the wire rope 40 repeatedly over a long period of time. Furthermore, by separating the covering portion 45, the portion of the main rope portion 41 covered by the covering portion 45 can be visually inspected, making it easy to check for damage or deterioration. Furthermore, if the covering portion 45 of the wire rope 40 is made transparent, the portion of the main rope portion 41 covered by the covering portion 45 can be visually inspected without separating or shifting the covering portion 45, making it even easier to check for damage or deterioration.

[0056] When the crane 20 is positioned with the back of the intermediate boom 232 of the boom 23 facing upward, a first locking projection 33 is provided on the back side and a second locking projection 34 is provided on the front side. Therefore, it is possible to suitably accommodate the requirement of securing wire ropes to both the upper and lower sides of the intermediate boom 232. For example, when connecting the wire rope 40 to the upper side of the intermediate boom 232, the wire rope 40 should be connected to the first locking projection 33 provided on the upper side of the intermediate boom 232, and when connecting the wire rope 40 to the lower side of the intermediate boom 232, the main rope section 41 should be connected to the second locking projection 34 provided on the lower side of the intermediate boom 232.

[0057] [others] The embodiments of the present invention have been described above. However, the present invention is not limited to the embodiments described above. For example, a component integrally formed from a single member in an embodiment may be replaced with a component divided into multiple members that are connected or fixed to each other. Also, a component formed by connecting multiple members may be replaced with a component integrally formed from a single member. Furthermore, details shown in the embodiments can be modified as appropriate without departing from the spirit of the invention.

[0058] For example, a configuration in which the main rope section 41 of the wire rope 40 has four strands has been given as an example, but the number is not limited to the above and may be one to three or five or more.

[0059] Furthermore, while the example in Figure 2 above illustrates a method of rigging by engaging the first engaging portion 43 with the second engaging portion 44 provided at the same position on each of the multiple main rope portions 41, the method is not limited to this example. For example, as shown in Figure 7, by engaging the first engagement portion 43 of some main rope portions 41 with a second engagement portion 44 that is closer to the base end than the first engagement portion 43 of other main rope portions 41, it becomes possible to lift the object being lifted at an inclination. In other words, this makes it possible to meet requirements such as lifting the object being lifted at an inclination in a specific direction.

[0060] Furthermore, as shown in Figure 8, the first engaging portion 43 of the main rope portion 41 is not limited to being engaged with the second engaging portion 44, and the first engaging portion 43 may also be engaged with the binding ring 42. Also, if the connecting portion 411 at the base end of the main rope portion 41 is made of an endless ring body, the first engaging portion 43 may also be engaged with the connecting portion 411. In this case, the binding ring 42 functions as a "second engagement part" provided at the base end of the main rope section 41. In this case, the length of the folded-back main rope portion 41 can be made even shorter than when the first engaging portion 43 is connected to the second engaging portion 44, which is closest to the base end of the main rope portion 41, thus meeting the demand for further shortening of these lengths.

[0061] Furthermore, as shown in the wire rope 40A of Figure 9, the second engagement portion 44 may be provided directly in the middle of the main rope portion 41 without going through the branch rope portion 441. In this case, it becomes possible to prevent the branch rope section 441 from becoming entangled or accidentally getting caught.

[0062] Furthermore, as shown in the wire rope 40B of Figure 10, a main rope section 41B of a different length may be included in addition to the main rope section 41. For example, the main rope section 41B may be made shorter than the main rope section 41, and the first engaging section 43 of the main rope section 41 and the first engaging section 43 of the main rope section 41B may be connected to perform the lifting operation. In this case, the first engaging portion 43 of one of the main rope portions 41B can be interpreted as the "second engaging portion," and the main rope portion 41B can be interpreted as the "branched rope portion branched from the main rope portion." Therefore, even if the second engaging portion 44 and the branched rope portion 441 are not present in part or all of the main rope portion 41 or 41B, it can still be said that the configuration embodies the present invention as described in the claims.

[0063] Furthermore, the objects to which wire ropes 40, 40A, and 40B are used for lifting are not limited to boom attachments, but can be used for lifting various structures.

[0064] Furthermore, while the example shown illustrates the intermediate boom 232 as a boom attachment being rigged with its underside facing down and its back facing up, it is not limited to this configuration; it may also be rigged with its underside facing up and its back facing down. In that case, it is preferable to provide a first locking projection 33 that protrudes downward on the lower surface of the main member 31 on the ventral side, and a second locking projection 34 that protrudes upward on the upper surface of the main member on the dorsal side. When the crane is a mobile tower crane or the like, a jib is attached to the tip of the upright boom as a boom attachment that allows for tilted operation. In the case of such a crane, the jib may be disassembled and assembled with its back facing downwards and its underside facing upwards, and the above work example can suitably handle such cases. Furthermore, while a crawler crane was given as an example of a crane, the present invention is not limited to this. In addition to other mobile cranes such as wheel cranes, truck cranes, rough terrain cranes, and all-terrain cranes, it is applicable to all kinds of cranes, including tower cranes, overhead cranes, jib cranes, retractable cranes, stacker cranes, gantry cranes, unloaders, and foundation machinery such as earth drills. It is particularly effective for cranes whose booms have hollow sections such as truss structures. [Explanation of Symbols]

[0065] 20 Cranes 221. Swivel frame (crane body) 23. Boom (Boom Attachment) 231 Lower boom (boom attachment) 232 Intermediate boom (boom attachment) 233 Upper boom (boom attachment) 31 Main component 32 Auxiliary materials 33 1st locked protrusion 331 Shaft 332 Expansion section 34 2nd locked protrusion 341 Locked plate 342 Base 343 Connecting member 40, 40A, 40B Wire Rope 41,41B Main rope section 411 Connection section 42 Cable Tie Rings 43 First engagement part 441 Branching rope section 45 Covering part F Hook T Transport Vehicle

Claims

1. The main rope section has a base end that can be connected to a crane hook, A first engaging portion is provided at the tip of the main rope portion that is opposite to the base end, A wire rope having, A second engaging portion is provided in the main rope portion at a position between the tip and base end, or at the base end, which is capable of engaging with the first engaging portion. The covering portion covers at least a portion of the main rope portion between the tip and the base end. Wire rope.

2. Multiple of the second engagement portions are provided along the longitudinal direction of the main rope portion. The wire rope according to claim 1.

3. The second engagement portion is provided on the main rope portion via a branch rope portion that branches off from the main rope portion, The covering portion covers at least a portion of the main rope portion between the tip portion and the branch rope portion. The wire rope according to claim 1.

4. The length of the branched rope section is shorter than the length of the branched rope section from the branching point to the tip of the main rope section. The wire rope according to claim 3.

5. The covering portion consists of a separate member that can be separated from the main rope portion. The wire rope according to claim 1.

6. The covering portion is transparent. The wire rope according to claim 1.

7. A crane having a crane body and a boom attachment that can be raised and lowered and attached to the crane body, When the boom attachment is positioned with one of its four longitudinal surfaces facing upwards, A first engaging portion is provided on the side of the boom attachment facing upwards, which is capable of securing a wire rope. A second engaging portion is provided on the lower side of the boom attachment, which is capable of securing the wire rope. crane.

Images