Rope entanglement prevention device and method for using grab bucket using rope entanglement prevention device
The rope entanglement prevention device maintains a distance between support and opening/closing ropes using sheaves and a swinging frame, addressing the issue of entanglement in grab buckets for stable operation.
Patent Information
- Application Number
- JP2024082333
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-05-21
- Publication Date
- 2025-12-04
Smart Images
Figure 2025176304000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to a rope entanglement prevention device and a method for using a grab bucket using the rope entanglement prevention device. [Background technology]
[0002] There are grab buckets of the so-called double-rope type that are operated by two rope-like members: a support rope that raises and lowers the grab bucket itself, and an opening / closing rope that opens and closes the grab bucket itself by letting out and reeling in.
[0003] For example, Patent Document 1 discloses a grab bucket in which the support ropes and the opening and closing ropes are attached and detached by inserting and removing the pins. By being provided with such a configuration, this grab bucket can be easily attached and detached to and from a crane.
[0004] Furthermore, Patent Document 2 discloses a grab bucket in which a support rope and an opening / closing rope are connected to a swivel part provided on a trolley, and the orientation can be changed by rotating the swivel part. [Prior art documents] [Patent documents]
[0005] [Patent Document 1] Jikko No. 43-9891 [Patent Document 2] Special Publication No. 39-28910 Summary of the Invention [Problem to be solved by the invention]
[0006] With such grab buckets, the bucket itself can rotate due to external forces when the grab bucket is in use, which can result in the support ropes and opening / closing ropes becoming tangled, making it difficult to raise, lower, open, or close the grab bucket.
[0007] The present invention has been made to solve the above-mentioned problems, and has an object to provide a rope entanglement prevention device that prevents the rope used to operate the grab bucket from becoming tangled, enabling stable operation of the grab bucket, and a method of using a grab bucket that uses the rope entanglement prevention device. [Means for solving the problem]
[0008] In order to achieve the above object, a rope entanglement prevention device according to a first aspect of the present invention comprises: an upper block having a connection portion to which a first rope is connected and an insertion portion through which a second rope is inserted, the upper block being suspended from the first rope; a lower block that is suspended by the second rope passed through the insertion portion and that rises or falls relative to the upper block as the second rope is wound or unwound relatively longer than the first rope; a pair of buckets connected to the upper block and supported by the lower block, the buckets opening and closing as the lower block rises or falls relative to the upper block; A rope entanglement prevention device for preventing entanglement of the first rope and the second rope, which is attached to a grab bucket comprising: a shaft attached to the upper block with its axis oriented horizontally and disposed between the first rope extending toward the connection portion of the upper block and the second rope extending toward the insertion portion of the upper block; a frame extending in a direction perpendicular to the shaft and capable of swinging about the shaft in one direction and the other direction of the extension direction; a first sheave provided at a first end of the frame in the one direction, around which the first rope extending toward the connection portion of the upper block is wound around an outer periphery of the frame in the one direction; a second sheave provided at a second end portion of the frame in the other direction, around which the second rope extending toward the insertion portion of the upper block is wound around an outer circumferential portion of the frame in the other direction; The present invention is characterized by comprising:
[0009] The shaft may be disposed between the connecting portion and the insertion portion with the axis directed in a direction in which the connecting portion and the insertion portion of the upper block are arranged.
[0010] The first sheave and the second sheave may be provided on the frame so as to be spaced apart in the arrangement direction by a distance from the connection portion to the insertion portion.
[0011] The rope entanglement prevention device further includes a third sheave that is provided on the upper block and arranged with its outer periphery positioned above the insertion portion of the grab bucket, The second rope extending from the lower block of the grab bucket and passed through the insertion portion is wound around the third sheave, The second rope may be wound around the second sheave after being wound around the third sheave.
[0012] The first sheave has a first guide member that faces an outer circumferential portion of the first sheave and guides the first rope between the outer circumferential portion and the first guide member, The second sheave may have a second guide member that faces an outer periphery of the first sheave and guides the first rope between the outer periphery and the second sheave.
[0013] The rope tangle prevention device further includes a base attached to the upper block and rotatably holding the shaft; The base may have a first elastic body that abuts against the frame when the frame swings in the one direction around the shaft, thereby determining the limit position of the swing, and a second elastic body that abuts against the frame when the frame swings in the other direction around the shaft, thereby determining the limit position of the swing.
[0014] A method of using a grab bucket using a rope entanglement prevention device according to a second aspect of the present invention includes: A method for using the grab bucket using the rope entanglement prevention device according to the first aspect, Attaching the shaft of the rope entanglement prevention device to the upper block of the grab bucket; a step of winding the first rope extending from the connection portion of the upper block around the first sheave, winding the second rope extending through the insertion portion of the upper block around the second sheave, and further connecting one of the first rope and the second rope to a main hoisting device provided in a crane, and connecting the other of the first rope and the second rope to an auxiliary hoisting device provided in the crane; Opening and closing the pair of buckets provided in the grab bucket by controlling the winding up or winding down of the first rope and the second rope by the main hoisting device and the auxiliary hoisting device; The present invention is characterized by comprising: [Effects of the Invention]
[0015] According to the configuration of the present invention, a first sheave around which a first rope is reeled and a second sheave around which a second rope is reeled are provided at the first end and second end of a frame, and the frame can swing in one direction toward the first end and the other direction toward the second end. Therefore, when the second rope is reeled out or reeled in longer than the first rope to open or close the bucket, the frame swings in one direction or the other depending on the difference between the force with which the first rope presses the first sheave and the force with which the second rope presses the second sheave. The first rope is then reeled around the first sheave, and the second rope is reeled around the second sheave. As a result, the rope entanglement prevention device maintains a distance between the first rope and the second rope, preventing the first rope and the second rope from becoming entangled. Furthermore, because the first rope is reeled around the first sheave and the second rope is reeled around the second sheave, the grab bucket can be operated stably. [Brief explanation of the drawings]
[0016] [Figure 1] FIG. 1 is a front view of a conventional double-rope grab bucket. [Figure 2] 1 is a front view of a grab bucket to which a rope entanglement prevention device according to an embodiment of the present invention is attached. FIG. [Figure 3] FIG. 1 is a right side view of a grab bucket to which a rope entanglement prevention device according to an embodiment is attached. [Figure 4] 1 is a front view of a rope entanglement prevention device according to an embodiment of the present invention and a grab bucket equipped with the rope entanglement prevention device. FIG. [Figure 5] 1 is a perspective view of a rope entanglement prevention device according to an embodiment of the present invention. FIG. [Figure 6] 1 is a front view of a rope entanglement prevention device according to an embodiment of the present invention. FIG. [Figure 7] FIG. 2 is a top view of the rope entanglement prevention device according to the present embodiment. [Figure 8] FIG. 2 is a right side view of the rope entanglement prevention device according to the present embodiment. [Figure 9] FIG. 7 is a cross-sectional view taken along the line IX-IX shown in FIG. 6. [Figure 10] 10 is a cross-sectional view taken along the line XX shown in FIG. 9. [Figure 11] 1 is a cross-sectional view showing a state in which the grab bucket of the rope entanglement prevention device according to the present embodiment is closed. FIG. [Figure 12] 1 is a cross-sectional view showing a state in which the grab bucket of the rope entanglement prevention device according to the present embodiment is opened. FIG. DETAILED DESCRIPTION OF THE INVENTION
[0017] A rope entanglement prevention device according to an embodiment of the present invention and a method of using a grab bucket using the rope entanglement prevention device will be described in detail below with reference to the drawings. In the drawings, identical or equivalent parts are designated by the same reference numerals. In the Cartesian coordinate system XYZ shown in the drawings, when a pair of grab buckets to which a rope entanglement prevention device is attached are hung with the buckets aligned in the left-right direction, the left-right direction is the X-axis, the up-down direction is the Z-axis, and the direction perpendicular to the X-axis and Z-axis is the Y-axis. The right side is the +X side, the upper side is the +Z side, and the front side is the +Y side. This coordinate system will be referenced where appropriate in the following description.
[0018] The rope entanglement prevention device according to the embodiment is a device that is attached to a double-rope grab bucket that is operated by a support wire rope and an opening / closing wire rope, and prevents the support wire rope and the opening / closing wire rope from entangling. First, the configuration of the grab bucket, which is the target of this rope entanglement prevention device, will be described in detail using a conventional double-rope grab bucket as an example.
[0019] A grab bucket is a device that is suspended by construction machinery. The configuration of the grab bucket will be explained below using an example in which the construction machinery is a crane. Although a grab bucket is also called a clamshell bucket, the following explanation will use the term grab bucket.
[0020] Fig. 1 is a front view of a conventional double-rope grab bucket 100. In Fig. 1, for ease of understanding, buckets 130, 140 in the open state are shown by dotted lines.
[0021] As shown in FIG. 1, the grab bucket 100 includes an upper block 110, a lower block 120, and a pair of buckets 130 and 140.
[0022] The upper block 110 is a member that is suspended from a crane and raised and lowered by the crane. Explaining its configuration in detail, the upper block 110 has the shape of a rectangular parallelepiped box with an open bottom. The upper surface of the upper block 110 has a connection part 111 that pins a wire socket provided at the end of the support wire rope 2 extending from the crane. This connects the upper block 110 to the support wire rope 2. While suspended by the crane, the upper block 110 rises or falls as the crane winds or unwinds the support wire rope 2. The supporting wire rope 2 is a specific example of the first rope referred to in the claims and will be simply referred to as the supporting rope 2 hereinafter.
[0023] The upper block 110 also has a rope guide 112 through which the opening and closing wire rope 4 is inserted in order to suspend the lower block 120 below the upper block 110. The rope guide 112 (a specific example of the insertion part referred to in the claims) passes through the upper block 110 in the vertical direction, and the opening and closing wire rope 4 is inserted therethrough. After being passed through the rope guide 112, the opening and closing wire rope 4 extends to the lower block 120. The opening and closing wire rope 4 is a specific example of the second rope referred to in the claims, and will be simply referred to as the opening and closing rope 4 hereinafter.
[0024] The lower block 120 is a member that opens and closes the pair of buckets 130, 140 by ascending or descending relative to the upper block 110. The lower block 120 has a plurality of lower sheaves 121 around which the opening and closing ropes 4 are wound, in order to ascend or descend by winding or unwinding the opening and closing ropes 4.
[0025] The above-mentioned upper block 110 has an upper sheave 113 around which the opening / closing rope 4 is wound, and a fixing part 114 for pinning a wire socket at the end of the opening / closing rope 4. The opening / closing rope 4 passed through a rope guide 112 is wound around the lower sheave 121, and the opening / closing rope 4 is further routed around the upper sheave 113. The opening / closing rope 4 routed around the upper sheave 113 is again routed around another lower sheave 121, and the end of the opening / closing rope 4 is fixed to the fixing part 114 of the upper block 110. With this configuration, the lower block 120 rises or falls relative to the upper block 110 when the opening / closing rope 4 is wound or unwound.
[0026] Meanwhile, each of the buckets 130, 140 has a roughly triangular prism shape. Specifically, each of the buckets 130, 140 has a hollow interior with an opening on one side 131, 141 of the three sides of the roughly triangular prism to accommodate sediment. Furthermore, the axis of each of the roughly triangular prisms of the buckets 130, 140 faces the front-to-rear direction. Bases 133, 143 supporting the sides 131, 141 with the openings face each other. In this state, the bases 133, 143 are connected to the lower block 120 by pins 122. As a result, the buckets 130, 140 are held by the lower block 120 in a rotatable state around the pins 122.
[0027] Furthermore, in the buckets 130 and 140, end portions 135 and 145 of the side surfaces 134 and 144 adjacent to the base portions 133 and 143 are supported by connecting members 115 and 116 extending from the upper block 110. These connecting members 115 and 116 are rotatably held by the upper block 110. The connecting members 115 and 116 are also connected to the buckets 130 and 140 by pins 136 and 146. As a result, the buckets 130 and 140 are movable left and right and are rotatable about the pins 136 and 146.
[0028] With this configuration, the buckets 130, 140 are so configured that when the opening / closing ropes 4 are unwound longer than the support ropes 2 and the lower block 120 descends relative to the upper block 110, the pins 122 descend, causing the bases 133, 143 to also descend. Since the ends 135, 145 of the buckets 130, 140 are supported by the upper block 110, the buckets 130, 140 rotate about the pins 136, 146 of the ends 135, 145, changing the side surfaces 131, 141 from facing each other to being separated from each other. This opens the openings of the buckets 130, 140.
[0029] On the other hand, when the opening / closing ropes 4 are wound longer than the support ropes 2 and the lower block 120 rises relative to the upper block 110, the pins 122 rise, causing the bases 133, 143 to also rise. Then, the buckets 130, 140 rotate about the pins 136, 146 of the end portions 135, 145, changing the side surfaces 131, 141 from a state separated from each other to a state facing each other. This closes the openings of the buckets 130, 140.
[0030] In this way, in the grab bucket 100, the opening / closing rope 4 is unwound longer than the support rope 2, or the opening / closing rope 4 is wound longer than the support rope 2, thereby opening and closing the buckets 130, 140.
[0031] However, when the grab bucket 100 is in use, if an external force is applied to the grab bucket 100 and it rotates in the vertical direction, the opening / closing ropes 4 and the support ropes 2 become entangled, and as a result, the grab bucket 100 itself may not be able to be raised or lowered even if the support ropes 2 are let out or reeled in. Also, the buckets 130, 140 may not be able to be opened or closed even if the opening / closing ropes 4 are let out or reeled in.
[0032] For example, when dredging work is performed using the grab bucket 100, the buckets 130, 140 may rotate due to the flow of water, resulting in the opening / closing ropes 4 and the support ropes 2 becoming entangled. Then, by letting out or reeling in the support ropes 2 or the opening / closing ropes 4, it may become impossible to operate the position or open / close the grab bucket 100.
[0033] Therefore, in order to prevent the support ropes 2 and the opening / closing ropes 4 from becoming entangled, a rope entanglement prevention device 1 is attached to the grab bucket 100. In this embodiment, in order to make the support ropes 2 and the opening / closing ropes 4 less likely to become entangled, an improved grab bucket 200 is used instead of the grab bucket 100. Next, with reference to Figures 2 to 4, the configurations of the grab bucket 200 and the rope entanglement prevention device 1 will be described. First, the configuration of the grab bucket 200 will be described.
[0034] 2 and 3 are a front view and a right side view of a grab bucket 200 to which a rope entanglement prevention device 1 according to this embodiment is attached. Fig. 4 is a front view of the rope entanglement prevention device 1 according to this embodiment and the grab bucket 200 to which the rope entanglement prevention device 1 is attached.
[0035] As shown in Fig. 2, the grab bucket 200 to which the rope entanglement prevention device 1 is attached includes an upper block 210 that is wider than the above-mentioned upper block 110. The grab bucket 200 also includes a lower block 120 and a pair of buckets 130, 140, the configuration of which is the same as that of the conventional grab bucket 100. Therefore, only the configuration of the upper block 210 will be described below.
[0036] The upper block 210 extends longer in the left-right direction than the above-described upper block 110. The right and left ends of the upper block 210 are provided with connection parts 211 and 212 for connecting the support ropes 2. These connection parts 211 and 212 have the same configuration as the above-described connection part 111. As a result, the support ropes 2 and 3 are connected to the connection parts 211 and 212, as shown in FIG. 4.
[0037] The support ropes 2, 3 extend from both ends of the support rod 5, which extends in the left-right direction. They have the same length. The distance between the connection points of the support ropes 2, 3 at both ends of the support rod 5 is the same as the distance between the connection points 211, 212. With this configuration, the upper block 210 is suspended horizontally by the support rod 5.
[0038] At this time, when the extension direction of the support rod 5 is oriented in a certain direction, a force is applied to the upper block 210 from the support ropes 2 and 3 that tries to orient the arrangement direction of the connection parts 211 and 212 in the extension direction of the support rod 5. As a result, the support rod 5 maintains its own extension direction, and tries to return the upper block 210 to its original position when the upper block 210 is rotated by an external force. As a result, the upper block 210 is less likely to rotate once, and the support ropes 2 and 3 are less likely to become tangled.
[0039] Returning to Fig. 2, rope guides 213 and 214 are provided between the connection parts 211 and 212. As shown in Fig. 3, the rope guides 213 and 214 are arranged in a row in the left-right direction together with the connection parts 211 and 212. The rope guides 213 and 214 have the same configuration as the rope guide 112 described above. As a result, the opening / closing rope 4 is passed through the rope guides 213 and 214.
[0040] The opening / closing rope 4 is passed through the two rope guides 213, 214 in a manner different from that of the rope guide 112 of the grab bucket 100 described above, in order to pass one opening / closing rope 4 through the two rope guides 213, 214. In detail, as shown in FIG. 4 , the opening / closing rope 4 is passed through the rope guide 213, then looped around a lower sheave 121 provided in the lower block 120, and further looped around an upper sheave 113 provided in the upper block 210. Then, after being looped around the upper sheave 113, the opening / closing rope 4 is again looped around another lower sheave 121, passes through the rope guide 214, and heads upward. In this way, the opening / closing rope 4 is passed through the rope guide 213, then looped around the lower sheave 121 and the upper sheave 113, and then passed through the rope guide 214.
[0041] Furthermore, one end and the other end of the opening / closing rope 4 are connected to the +X end and -X end of the support rod 6 extending in the left-right direction, i.e., in the X direction. The distance between the connection points of the opening / closing rope 4 at the +X end and the -X end is the same as the distance between the rope guides 213, 214. The opening / closing rope 4 suspends the lower block 120 from the support rod 6 by being connected in this way and looped around the lower sheave 121 and upper sheave 113 described above.
[0042] Meanwhile, as described above, the opening / closing ropes 4 are passed through the rope guides 213 and 214. For this reason, when the extension direction of the support rods 6 is oriented in a certain direction in the suspended state, a force is applied to the upper block 210 from the opening / closing ropes 4 to orient the arrangement direction of the rope guides 213 and 214 in the extension direction of the support rods 6. As a result, similar to the support rods 5, the extension direction of the support rods 6 themselves is oriented in the same direction as the extension direction of the support rods 5, and this orientation is maintained, so that even if the upper block 210 is rotated by an external force, the upper block 210 is returned to its original position, making it less likely that the support ropes 2 and 3 will become entangled.
[0043] The support rods 5 and 6 are suspended from an auxiliary hoisting hook 7 and a main hoisting hook 8 provided on the crane. The support rods 5 and 6 are raised or lowered by the crane winding or unwinding the wire rope connected to the auxiliary hoisting hook 7 and the main hoisting hook 8. As a result, the grab bucket 200 itself can be moved to a desired position by raising or lowering the upper block 210, or the grab bucket 200 can be opened or closed by raising or lowering the lower block 120 relative to the upper block 210.
[0044] However, when the auxiliary hook 7 and the main hook 8 suspend the support rods 5 and 6, it is difficult to orient the extension direction of the support rods 5 and 6 in a specific direction and maintain that direction. It is also difficult to keep the support rods 5 and 6 parallel to each other. As a result, it is difficult to prevent the support ropes 2 and 3 from becoming entangled with the opening and closing rope 4. Furthermore, if the horizontal distance between the auxiliary hook 7 and the main hook 8 is small, the support ropes 2 and 3 and the opening and closing rope 4 are likely to become entangled.
[0045] Therefore, a rope entanglement prevention device 1 is attached to the grab bucket 200 to prevent entanglement of the support ropes 2, 3 and the opening / closing rope 4. Next, the configuration of the rope entanglement prevention device 1 will be described in detail with reference to Figs. 5 to 12.
[0046] Fig. 5 is a perspective view of the rope entanglement prevention device 1 according to this embodiment. Figs. 6 to 8 are a front view, a top view, and a right side view of the rope entanglement prevention device 1. Fig. 9 is a cross-sectional view taken along the IX-IX section line shown in Fig. 6. Fig. 10 is a cross-sectional view taken along the XX section line shown in Fig. 9. Fig. 11 is a cross-sectional view showing the rope entanglement prevention device 1 in a state where the buckets 130, 140 of the grab bucket 200 are closed. Fig. 12 is a cross-sectional view showing the rope entanglement prevention device 1 in a state where the buckets 130, 140 of the grab bucket 200 are opened. Note that Figs. 11 and 12 show cross sections taken along the same section line as Fig. 9.
[0047] As shown in Figure 5, the rope entanglement prevention device 1 comprises a base 10 attached to the grab bucket 200, and swing mechanisms 20, 30 provided on the base 10 and swinging between the support ropes 2, 3 and the opening / closing rope 4 in response to the force applied from the support ropes 2, 3 and the opening / closing rope 4.
[0048] The base 10 is a member that is placed on and attached to the upper block 210 of the grab bucket 200. The base 10 is formed in a flat plate shape so that it can be placed on the upper block 210. The width W1 of the base 10 is smaller than the distance D1 from the connection portion 211 to the connection portion 212 shown in FIG. 2 . As a result, when the base 10 is placed on the upper block 210 of the grab bucket 200, the support ropes 2 and 3 are passed through the left and right sides of the base 10. As a result, the base 10 is prevented from becoming an obstacle when the support ropes 2 and 3 are connected to the connection portions 211 and 212 of the upper block 210. In addition, through holes h1 and h2 for passing the opening / closing rope 4 are formed near the center of the plate surface of the base 10. As a result, the base 10 is prevented from becoming an obstacle when the opening / closing rope 4 is inserted into the rope guides 213 and 214 of the upper block 210. The base 10 is attached to the upper block 210 with a fastening member such as a bolt, with the plate surface of the base 10 in contact with the upper surface of the upper block 210.
[0049] Furthermore, the front and rear ends of the flat plate of base 10, i.e., the +Y end and the -Y end, are bent toward the +Z side. The bent +Y end of base 10 is provided with rubber stoppers 11 and 12 (specific examples of the "first elastic body" in the claims) that define the swing limit positions of swing mechanisms 20 and 30 when they swing in the Y direction, as shown in Figs. 6 and 7. Similarly, the bent -Y end of base 10 is provided with rubber stoppers 13 and 14 (specific examples of the "second elastic body" in the claims) that define the swing limit positions of swing mechanisms 20 and 30, as shown in Fig. 7. These stoppers 11 and 14 are formed in the shape of a tube extending in the X direction and absorb the impact when swing mechanisms 20 and 30 hit them.
[0050] On the other hand, on the +Z side of the base 10, swing mechanisms 20 and 30 are provided side by side in the X direction.
[0051] The swing mechanisms 20, 30 are mechanisms that maintain the distance between the support ropes 2, 3 and the opening / closing rope 4, preventing the support ropes 2, 3 and the opening / closing rope 4 from becoming entangled. To maintain the distance between these ropes and prevent them from becoming entangled, the swing mechanism 20 includes a shaft 21 provided on the base 10, a frame 22 supported by the shaft 21, a front sheave 23 and a rear sheave 24 provided on the frame 22, and a base sheave 25 provided on the base 10, as shown in Figures 5 and 6.
[0052] Like the swing mechanism 20, the swing mechanism 30 includes a shaft 31, a frame 32, a front sheave 33, a rear sheave 34, and a base sheave 35. The swing mechanism 30 has a shape and arrangement that are bilaterally symmetrical to the swing mechanism 20. That is, the swing mechanisms 20 and 30 are configured symmetrically with respect to the IX-IX section line shown in FIG. 6 or the center line L1 that passes through the center of the base 10 in the X direction shown in FIG. 7. For this reason, only the components of the swing mechanism 20 will be described below, and a description of the components of the swing mechanism 30 will be omitted.
[0053] As shown in Figures 5 and 6, the shaft 21 is rotatably supported by support plates 215 and 216 that protrude from the base 10 toward the +Z side. More specifically, the support plates 215 and 216 are fixed to the base 10 with their plate surfaces facing the X direction and a distance between them. Although not shown, each of the support plates 215 and 216 has a bearing fitted in a through-hole that passes through the plate surface. The shaft 21 is rotatably held by these bearings with its axis facing the X direction. Meanwhile, the frame 22 is connected to a portion of the shaft 21 that is located between the support plates 215 and 216.
[0054] As shown in Fig. 5, frame 22 has a shape roughly like a triangular prism laid on its side. More specifically, frame 22 is formed by combining multiple pipes to have a triangular prism shape with an isosceles triangular base and a prism axis oriented in the X direction. Frame 22 is fixed to shaft 21 with vertex 223 formed by pipes 221 and 222 shown in Fig. 8, which form the equilateral sides of the isosceles triangle, facing shaft 21. As a result, in frame 22, pipe 224, which forms the base of the isosceles triangle, can swing around the axis of shaft 21.
[0055] As shown in Fig. 4, in the upper block 210 of the grab bucket 200, the connection parts 211 and 212 and the rope guides 213 and 214 are arranged in a straight line. With the base 10 attached to the upper block 210, the shaft 21 is arranged with its axis facing in the same direction on the straight line on which the connection parts 211 and 212 and the rope guides 213 and 214 are arranged. This same direction is the X direction. As a result, the above-mentioned pipe 224 shown in Fig. 5 can swing to the +Y side and -Y side of the connection parts 211 and 212 and the rope guides 213 and 214, i.e., forward F and backward B. A front sheave 23 and a rear sheave 24 are provided at the front end and rear end of the pipe 224, respectively.
[0056] As shown in FIG. 5 , the frame 22 is provided with a pipe 225 located to the left L of the pipe 224 and extending parallel to the pipe 224. Also provided is a pipe 226 joined to the front ends of the pipes 224 and 225, extending to the right R of the pipes 224 and extending to the outside of the base 10 (note that the front end where the pipe 226 is located is a specific example of the first end in the claims, and the rear B is a specific example of the first direction in the claims). The front sheave 23 (a specific example of the first sheave in the claims) is provided at the right end of the pipe 226. Although not shown, a bearing is provided at the right end of the pipe 226, and the shaft of the front sheave 23 is held by the bearing. This allows the front sheave 23 to rotate around that shaft.
[0057] Furthermore, a groove is formed on the outer periphery of the front sheave 23, and the support rope 2 is wound around this groove from the front F side, as shown in Figures 11 and 12. The front sheave 23 is rotatable around its axis, allowing the wound support rope 2 to be smoothly wound up and let out.
[0058] Furthermore, in order to prevent the wound support ropes 2 from coming off, the front sheave 23 is provided with a bar member 231 (a specific example of a first guide member as defined in the claims) that faces the groove on the outer periphery of the front sheave 23. The bar member 231 forms a space between the groove on the outer periphery of the front sheave 23 and the bar member 231, through which the support ropes 2 can pass, and guides the support ropes 2 into that space. As a result, the front sheave 23 is prevented from coming off due to fluctuations in the position of the front sheave 23 caused by the swinging of the frame 22.
[0059] Returning to FIG. 5, the frame 22 is provided with a pipe 227 that is joined to the rear end of the pipe 224 and the rear end of the pipe 225 and extends to the left side L of the pipe 225 (note that the rear end where the pipe 227 is located is a specific example of the second end as defined in the claims, and the rear B is a specific example of the second direction as defined in the claims). The rear sheave 24 (a specific example of the second sheave as defined in the claims) is provided at the left end of the pipe 227. Although not shown, a bearing is also provided at the left end of the pipe 227, as in the case of the pipe 226, and the shaft of the rear sheave 24 is held by the bearing. This allows the rear sheave 24 to rotate around that shaft.
[0060] Furthermore, the rear sheave 24 has a groove on its outer periphery, similar to the front sheave 23. As shown in Figures 11 and 12, the opening and closing rope 4 is wound around the groove of the rear sheave 24 from the rear B side. The rear sheave 24 also has a rotatable shaft, allowing the wound opening and closing rope 4 to be smoothly wound and unwound.
[0061] 5, the left end of the above-mentioned pipe 227 on which the rear sheave 24 is located is provided at a position spaced a distance D2 from the right end of the pipe 226 on which the front sheave 23 is located. The distance D2 is the same as the distance from the center of the connection part 211 to the center of the rope guide 213 on the upper block 210 of the grab bucket 200 shown in FIG. 2. The rear sheave 24 has such a configuration, and the opening / closing ropes 4 are wound around it, thereby maintaining the pitch between the opening / closing ropes 4 and the support ropes 2 wound around the front sheave 23 at the pitch from the connection part 211 to the rope guide 213.
[0062] Furthermore, when the pipes 224 and 225 of the frame 22 shown in Figure 5 are horizontal, the horizontal distance D3 from the front end of the front sheave 23 to the rear end of the rear sheave 24 is greater than the distance between the auxiliary hook 7 and the main hook 8 of the crane described above. When a frame 22 of this size swings and tilts the pipes 224 and 225 shown in Figures 11 and 12, the horizontal distance D4 from the front end of the front sheave 23 to the rear end of the rear sheave 24 is approximately the same as the horizontal distance between the auxiliary hook 7 and the main hook 8 shown in Figure 4. The front sheave 23 and the rear sheave 24 have this positional relationship, so that the distance between the support rope 2 and the opening / closing rope 4 is the same as the distance between the auxiliary hook 7 and the main hook 8. This allows the front sheave 23 and the rear sheave 24 to prevent the support rope 2 and the opening / closing rope 4 from becoming entangled.
[0063] Furthermore, in order to prevent the opening and closing ropes 4 that have been wound around them from coming off, the rear sheave 24 has a bar member 241 (a specific example of a second guide member as defined in the claims) that has the same structure as the bar member 231 described above, as shown in Figures 11 and 12. Like the bar member 231, the bar member 241 also forms a space between itself and the groove on the outer periphery of the rear sheave 24 through which the opening and closing ropes 4 can pass, and guides the opening and closing ropes 4 into that space. As a result, the rear sheave 24 prevents the opening and closing ropes 4 from coming off as a result of the frame 22 swinging. The opening and closing ropes 4 are further wound around the base sheave 25.
[0064] The base sheave 25 (an example of the third sheave referred to in the claims) is provided to prevent the opening / closing rope 4 from being difficult to flow into the rope guide 213 in the upper block 210 of the grab bucket 200 when the rear sheave 24 swings due to the frame 22. The base sheave 25 is provided on the base 10 so that its position does not change due to the swinging of the frame 22.
[0065] 6, in addition to the support plate 216 described above, the base 10 is provided with a support plate 217 that protrudes from the base 10 and faces the support plate 216. The shaft of the base sheave 25 is rotatably held by bearings (not shown) that are provided on the support plates 216 and 217. In this way, the base sheave 25 is rotatably supported by the support plates 216 and 217.
[0066] The base sheave 25 is disposed closer to the base 10 than the rear sheave 24 by support plates 216 and 217 so that the opening / closing ropes 4 after being reeled around the rear sheave 24 are reeled around. The base sheave 25 has a groove on its outer periphery, similar to the front sheave 23 and the rear sheave 24. As shown in FIGS. 11 and 12 , the opening / closing ropes 4 after being reeled around the rear sheave 24 from the rear B side are reeled around the groove of the base sheave 25 from the front F side. The base sheave 25 is disposed at a position where the front end of its outer periphery is located directly above the shaft 21. That is, the front end of the base sheave 25 is located directly above the through-hole h2 of the base 10, as shown in FIG. 7 . As a result, the base sheave 25 guides the reeled opening / closing ropes 4 to the rope guide 213 in the upper block 210 of the grab bucket 200 shown in FIG. 4 . At this time, since the axis of the base sheave 25 is rotatably held, the base sheave 25 smoothly guides the opening / closing rope 4 to the rope guide 213 .
[0067] Furthermore, in order to prevent the opening / closing ropes 4 wound around the base sheave 25 from coming off, a bar member 251 is provided on the front F side as shown in Figs. 11 and 12, facing the groove on the outer periphery of the base sheave 25. As shown in Fig. 10, the bar member 251 forms a space between itself and the groove on the outer periphery of the base sheave 25. Although not shown, the opening / closing ropes 4 are passed through this space. In this way, the bar member 251 guides the opening / closing ropes 4 into the groove on the outer periphery of the base sheave 25. The bar member 251 also prevents the opening / closing ropes 4 from coming off the base sheave 25 when the rear sheave 24 moves due to the swinging of the frame 22.
[0068] As described above, the swing mechanism 20, having the above-described configuration, maintains the distance between the support ropes 2 and the opening / closing ropes 4 at the distance from the crane's auxiliary winding hook 7 to the main winding hook 8, preventing the support ropes 2 and the opening / closing ropes 4 from becoming entangled. Although not described in detail, the swing mechanism 30, which is symmetrical to the swing mechanism 20, maintains the distance between the support ropes 3 and the opening / closing ropes 4 at the distance from the crane's auxiliary winding hook 7 to the main winding hook 8, preventing the support ropes 3 and the opening / closing ropes 4 from becoming entangled. Furthermore, the swing mechanisms 20 and 30 maintain the same distance between the support ropes 2 and the opening / closing ropes 4 and the distance between the support ropes 3 and the opening / closing ropes 4. This ensures that the support rod 5 suspending the support ropes 2 and 3 and the support rod 6 suspending the ends of the opening / closing ropes 4 shown in FIG. 4 are parallel to each other. This makes the support ropes 2 and 3 and the opening / closing rope 4 less likely to twist.
[0069] Next, the method of using the rope entanglement prevention device 1 and its operation will be described with reference to FIGS.
[0070] First, as shown in FIG. 4, the rope entanglement prevention device 1 is placed on the upper block 210 provided on the grab bucket 200, and in this state, the rope entanglement prevention device 1 is attached to the upper block 210 using a fastening member such as a bolt.
[0071] Next, the opening / closing rope 4 attached to the grab bucket 200 is passed through the through hole h2 of the base 10 of the rope entanglement prevention device 1, and then reeled around the base sheave 25 and rear sheave 24 of the rope entanglement prevention device 1 in the arrangement described above. Also, the opening / closing rope 4 is passed through the through hole h1 of the base 10 of the rope entanglement prevention device 1, and then reeled around the base sheave 35 and rear sheave 34 in the same arrangement. Then, the reeled opening / closing rope 4 is attached to the support rod 6, and the support rod 6 is hung from the main reeling hook 8.
[0072] The support rope 2 attached to the grab bucket 200 is reeled around the front sheave 23 in the arrangement described above. The support rope 3 attached to the grab bucket 200 is reeled around the front sheave 33 in the same manner as the front sheave 23. The reeled support ropes 2, 3 are then attached to a support rod 5, and the support rod 5 is hung from the auxiliary winding hook 7.
[0073] With the above, the installation of the rope entanglement prevention device 1 on the grab bucket 200 is completed. Thereafter, for example, when opening the buckets 130, 140 of the grab bucket 200, the main hoisting device provided on the crane is caused to wind down the wire rope to which the main hoisting hook 8 is connected. Alternatively, the auxiliary hoisting device provided on the crane is caused to wind up the wire rope to which the auxiliary hoisting hook 7 is connected. This causes the opening / closing rope 4 to be reeled out relatively longer than the support ropes 2, 3. As a result, the lower block 120 of the grab bucket 200 descends relative to the upper block 210. This causes the buckets 130, 140 to open.
[0074] At this time, a stronger force is applied to the support ropes 2, 3 than to the opening / closing rope 4. As a result, as shown in FIG. 11 , the support rope 2 hangs straight down toward the connection part 211 on the upper block 210 of the grab bucket 200. This causes the support rope 2 to push the front sheave 23 backward B, causing the frame 22 to swing. As a result, the rear sheave 24 moves backward B.
[0075] The frame 22 keeps the front sheave 23 and the rear sheave 24 separated in the front-to-rear direction. This maintains a distance between the support rope 2 wound around the front sheave 23 and the opening / closing rope 4 wound around the rear sheave 24. As a result, the support rope 2 and the opening / closing rope 4 are prevented from becoming entangled.
[0076] Additionally, the opening / closing rope 4 hanging down from above is looped around the rear sheave 24 that has moved rearward B. After being looped around the rear sheave 24, the opening / closing rope 4 is looped around the base sheave 25 and headed toward the rope guide 213 below. This allows the opening / closing rope 4 to be smoothly let out or reeled in. As a result, the opening and closing operations of the buckets 130, 140 are easy.
[0077] Note that the operation has been explained using the configuration of the swing mechanism 20 provided in the rope entanglement prevention device 1, but although not shown, in the swing mechanism 30 as well, the support ropes 3 push the front sheave 33 backward B, causing the frame 22 to swing. Then, the rear sheave 34 moves backward B. Although the routing of the support ropes 3 will not be explained in detail, the front sheave 33 and the rear sheave 34 also maintain a distance between the support ropes 3 and the opening / closing ropes 4. As a result, entanglement of the support ropes 3 and the opening / closing ropes 4 is prevented. Furthermore, the swing mechanism 30 also makes it easy to open and close the buckets 130, 140.
[0078] On the other hand, when closing the buckets 130, 140 of the grab bucket 200, the main hoisting device provided on the crane is made to hoist up the wire rope to which the main hoisting hook 8 is connected. Alternatively, the auxiliary hoisting device provided on the crane is made to hoist down the wire rope to which the auxiliary hoisting hook 7 is connected. As a result, the support ropes 2, 3 are let out relatively longer than the opening / closing rope 4. This causes the lower block 120 of the grab bucket 200 to rise relative to the upper block 210. As a result, the buckets 130, 140 close.
[0079] At this time, a stronger force is applied to the opening / closing ropes 4 than to the support ropes 2, 3. As a result, as shown in FIG. 12, the opening / closing ropes 4 hang straight down toward the rope guide 213 in the upper block 210 of the grab bucket 200. This causes the opening / closing ropes 4 to push the rear sheave 24 forward F, causing the frame 22 to swing. As a result, the front sheave 23 moves forward F.
[0080] In this case, too, the frame 22 keeps the front sheave 23 and the rear sheave 24 separated in the front-to-rear direction. This maintains a distance between the support rope 2 looped around the front sheave 23 and the opening / closing rope 4 looped around the rear sheave 24. As a result, the support rope 2 and the opening / closing rope 4 are prevented from becoming entangled.
[0081] In addition, the support rope 2 is wound around the front sheave 23 that has moved forward F. The support rope 2 extends from a connection part 211 in the upper block 210 of the grab bucket 200 and is then wound around the front sheave 23, so that it can be smoothly let out or reeled in. As a result, the opening and closing operations of the buckets 130, 140 are easy.
[0082] Although not shown, in the swing mechanism 30, the opening and closing ropes 4 similarly push the rear sheave 34 forward F to swing the frame 32. As a result, the front sheave 33 moves forward F. Although the routing of the opening and closing ropes 4 will not be described in detail, the front sheave 33 and rear sheave 34 also maintain a distance between the support ropes 3 and the opening and closing ropes 4. As a result, entanglement of the support ropes 3 and the opening and closing ropes 4 is prevented. Furthermore, the swing mechanism 30 also makes it easy to open and close the buckets 130, 140.
[0083] In this way, in the rope entanglement prevention device 1, whether the buckets 130, 140 of the grab bucket 200 are opened or closed, the frame 22 keeps the front sheaves 23, 33 and the rear sheaves 24, 34 separated in the fore-and-aft direction, thereby preventing the support ropes 2, 3 and the opening / closing rope 4 from becoming entangled.
[0084] As described above, in the rope entanglement prevention device 1 according to the embodiment, the front sheaves 23, 33 around which the support ropes 2, 3 are reeled and the rear sheaves 24, 34 around which the opening / closing rope 4 is reeled are provided at the front and rear ends of the frames 22, 32, respectively. The frames 22, 32 can swing forward F, which is the front end side, and rear B, which is the rear end side. Therefore, when the opening / closing rope 4 is reeled out or reeled in to a length relatively longer than the support ropes 2, 3 in order to open or close the buckets 130, 140, the frames 22, 32 swing forward F and rear B depending on the difference between the force with which the support ropes 2, 3 press against the front sheaves 23, 33 and the force with which the opening / closing rope 4 presses against the rear sheaves 24, 34. The support ropes 2, 3 are reeled around the front sheaves 23, 33, and the opening / closing rope 4 is reeled around the rear sheaves 24, 34, maintaining a state in which the support ropes 2, 3 are reeled around the front sheaves 23, 33, and the opening / closing rope 4 is reeled around the rear sheaves 24, 34. As a result, the rope entanglement prevention device 1 maintains a distance between the support ropes 2, 3 and the opening / closing rope 4, preventing the support ropes 2, 3 from becoming entangled with the opening / closing rope 4. Furthermore, the rope entanglement prevention device 1 maintains a state in which the support ropes 2, 3 are looped around the front sheaves 23, 33 and the opening / closing rope 4 is looped around the rear sheaves 24, 34, allowing for stable operation of the grab bucket 200.
[0085] The rope entanglement prevention device 1 also includes base sheaves 25, 35 around which the opening / closing rope 4 is reeled after being reeled around the rear sheave 24, and the base sheaves 25, 35 guide the opening / closing rope 4 after being reeled around them to rope guides 112, 213, 214 in the upper block 210 of the grab bucket 200. Therefore, the rope entanglement prevention device 1 can easily pay out or reel in the opening / closing rope 4. As a result, the grab bucket 200 can be operated stably.
[0086] The above describes the rope entanglement prevention device 1 according to the embodiment of the present invention and the method of using the grab bucket 200 using the rope entanglement prevention device 1, but the present invention is not limited to the embodiment.
[0087] For example, in the embodiment, the rope entanglement prevention device 1 includes the base 10, but the base 10 may have any configuration. In the rope entanglement prevention device 1, the shaft 21 may be attached directly to the grab bucket 100 or 200 without using the base 10. In this case, the shaft 21 may be rotatably held by a bearing attached to the grab bucket 100 or 200.
[0088] In the embodiment, the front sheaves 23, 33, the rear sheaves 24, 34, and the base sheaves 25, 35 are rotatable around the axes. However, whether the front sheaves 23, 33, the rear sheaves 24, 34, and the base sheaves 25, 35 are rotatable is optional in the present invention. In the present invention, it is sufficient that the support ropes 2, 3 are reeled around the front sheaves 23, 33, and the opening / closing rope 4 is reeled around the rear sheaves 24, 34. Also, in the present invention, it is sufficient that the opening / closing ropes 4 extending from the lower block 120 of the grab bucket 100, 200 and passing through rope guides 112, 213, 214 are reeled around the base sheaves 25, 35. In this case, it is preferable that the opening / closing ropes 4 reeled around the base sheaves 25, 35 are reeled around the rear sheaves 24, 34. For this reason, the front sheaves 23, 33, the rear sheaves 24, 34, and the base sheaves 25, 35 do not need to rotate. They may have outer peripheries that can guide the support ropes 2, 3 or the opening / closing ropes 4.
[0089] In the embodiment, a grab bucket 200 is used, but the grab bucket 200 may be a conventional grab bucket 100. In that case, the rope entanglement prevention device 1 may be equipped with either one of the swing mechanisms 20 or 30. This is because the grab bucket 100 has only one connection part 111 and one rope guide 112 on the upper block 110, and uses only one support rope 2 and one opening / closing wire rope 4.
[0090] Furthermore, when using a conventional grab bucket 100, the length of the frame 22, in other words, the length from the rear end where the rear sheave 24 is provided to the front end where the front sheave 23 is provided, should be longer than the distance from the connection part 111 in the upper block 110 to the rope guide 112. In this case, the shaft 21 should be positioned above and between the connection part 111 and the rope guide 112. Also, the axis of the shaft 21 should be perpendicular to the direction in which the connection part 111 and the rope guide 112 are arranged. This is because a frame 22 of such size and a shaft 21 arranged in such a manner can prevent the support ropes 2 and the opening / closing wire ropes 4 from becoming entangled.
[0091] In the present invention, the shafts 21, 31 are attached to the upper block 110 with their axes oriented horizontally, and are disposed between the support ropes 2, 3 extending toward the connecting parts 111, 211, 212 of the upper blocks 110, 210 and the opening / closing rope 4 extending toward the rope guides 112, 213, 214 of the upper blocks 110, 210. In this case, the frames 22, 32 are required to extend in a direction perpendicular to the shafts 21, 31 and to be able to swing about the shafts 21, 31 in one direction and the other direction of the extension direction. For example, when the shafts 21, 31 extend from the support ropes 2 or 3 parallel to the direction of the opening and closing ropes 4, the frames 22, 32 should extend with a width from the support ropes 2 or 3 to the opening and closing ropes 4 (for example, extending in a direction perpendicular to the pipes 226, 227 described above with a width in the left-right direction), and should be able to swing around the shafts 21, 31 in one direction and the other in the extension direction. This is because with such shafts 21, 31 and frames 22, 32, the distance between the support ropes 2, 3 and the opening and closing wire ropes 4 can be maintained. Alternatively, when the shafts 21, 31 extend from the support ropes 2 or 3 in a direction perpendicular to the direction of the opening and closing ropes 4, the frames 22, 32 should extend in a direction perpendicular to the shafts 21, 31 for a distance longer than the combined distance from the shafts 21, 31 to the connecting parts 111, 211, 212 of the upper blocks 110, 210 and the distance from the shafts 21, 31 to the rope guides 112, 213, 214 of the upper blocks 110, 210, and should be able to swing around the shafts in one direction and the other direction of extension. This is because such shafts 21, 31 and frames 22, 32 make it possible to maintain the distance between the support ropes 2, 3 and the opening and closing wire ropes 4.
[0092] In the embodiment, the frames 22 and 32 are frameworks in the shape of a triangular prism laid on its side. In other words, the frames 22 and 32 are frameworks with a truss structure. However, the frames 22 and 32 are not limited to this. In the present invention, as long as the above conditions are met, they may be, for example, T-shaped frameworks. Furthermore, although the frameworks of the frames 22 and 32 are formed from pipes, they may also be formed from solid rods.
[0093] In the embodiment, the grab buckets 100, 200 are provided with the upper sheave 113 and the lower sheave 121, but in the present invention, it is optional whether the upper blocks 110, 210 and the lower block 120 are provided with the upper sheave 113 and the lower sheave 121. The method of reeling the upper sheave 113 and the lower sheave 121 is also optional. For example, the lower block 120 may not be provided with the lower sheave 121 and may be directly suspended from the opening / closing wire rope 4.
[0094] In addition, in the embodiment, the pair of buckets 130, 140 of the grab buckets 100, 200 are arranged in the left-right direction, but the orientation is arbitrary. The left-right direction and front-rear direction referred to in the embodiment are merely for the convenience of explanation. As long as the positional relationship of each component of the rope entanglement prevention device 1 is maintained, for example, the pair of buckets 130, 140 may be oriented in the front-rear direction. [Explanation of symbols]
[0095] 1 Rope tangle prevention device 2, 3 Support rope 4 Opening and closing rope 5 Support rod 6 Support rod 7. Supplementary hook 8 Main winding hook 10 base 11-14 Stopper 20,30 Swing mechanism 21,31 Shaft 22,32 frames 23,33 forward sheave 24,34 Rear sheave 25,35 Base sheave 100 Grab Bucket 110 Upper Block 111 Connection 112 Rope Guide 113 Upper sheave 114 Fixed part 115,116 Connecting member 120 Lower Block 121 Lower sheave 122 pins 130,140 buckets 131,141 sides 133,143 base 134,144 sides 135,145 End 136,146 Pins 200 Grab Bucket 210 Upper Block 211,212 Connection 213,214 Rope guide 215-217 Support plate 223 Vertex part 221, 222, 224-227 Pipes 231, 241, 251 Bar members B Back F forward L1 center line L left side R right side D1,D2 distance D3,D4 horizontal distance h1,h2 through hole W1 width
Claims
1. an upper block having a connection portion to which a first rope is connected and an insertion portion through which a second rope is inserted, the upper block being suspended from the first rope; a lower block that is suspended by the second rope passed through the insertion portion and that rises or falls relative to the upper block as the second rope is wound or unwound relatively longer than the first rope; a pair of buckets connected to the upper block and supported by the lower block, the buckets opening and closing as the lower block rises or falls relative to the upper block; A rope entanglement prevention device for preventing entanglement of the first rope and the second rope, which is attached to a grab bucket comprising: a shaft attached to the upper block with its axis oriented horizontally and disposed between the first rope extending toward the connecting portion of the upper block and the second rope extending toward the insertion portion of the upper block; a frame extending in a direction perpendicular to the shaft and capable of swinging about the shaft in one direction and the other direction of the extension direction; a first sheave provided at a first end of the frame in the one direction, around which the first rope extending toward the connection portion of the upper block is wound around an outer periphery of the frame in the one direction; a second sheave provided at a second end portion of the frame in the other direction, around which the second rope extending toward the insertion portion of the upper block is wound around an outer periphery of the frame in the other direction; Equipped with Rope tangle prevention device.
2. the shaft is disposed between the connecting portion and the inserting portion with the axis directed in a direction in which the connecting portion and the inserting portion of the upper block are arranged; The rope entanglement prevention device according to claim 1.
3. The frame is provided with the first sheave and the second sheave spaced apart in the arrangement direction by a distance from the connection portion to the insertion portion. The rope entanglement prevention device according to claim 2.
4. Further, a third sheave is provided on the upper block and arranged in a state where an outer periphery thereof is positioned above the insertion portion of the grab bucket, The second rope extending from the lower block of the grab bucket and passed through the insertion portion is wound around the third sheave, The second rope after being wound around the third sheave is wound around the second sheave. A rope entanglement prevention device according to claim 1 or 2.
5. The first sheave has a first guide member that faces an outer circumferential portion of the first sheave and guides the first rope between the outer circumferential portion and the first guide member, The second sheave has a second guide member that faces an outer circumferential portion of the first sheave and guides the first rope between the second sheave and the outer circumferential portion. A rope entanglement prevention device according to claim 1 or 2.
6. a base attached to the upper block and rotatably holding the shaft; The base has a first elastic body that comes into contact with the frame when the frame swings about the shaft in the one direction to define a limit position of the swing, and a second elastic body that comes into contact with the frame when the frame swings about the shaft in the other direction to define a limit position of the swing. A rope entanglement prevention device according to claim 1 or 2.
7. A method for using the grab bucket using the rope entanglement prevention device according to claim 1 or 2, Attaching the shaft of the rope entanglement prevention device to the upper block of the grab bucket; a step of winding the first rope extending from the connection portion of the upper block around the first sheave, winding the second rope extending through the insertion portion of the upper block around the second sheave, and further connecting one of the first rope and the second rope to a main hoisting device provided in a crane, and connecting the other of the first rope and the second rope to an auxiliary hoisting device provided in the crane; opening and closing the pair of buckets provided in the grab bucket by controlling the winding up or winding down of the first rope and the second rope by the main hoisting device and the auxiliary hoisting device; Equipped with How to use a grab bucket with a rope tangle prevention device.
Citation Information
Patent Citations
JP9891Y
JP28910B
Cited By
Grab bucket anti-torsion device and salvage ship
CN121650836A