Hanging sheave

Abstract

To provide a hanging sheave capable of preventing a divergence of a mounting position of a snow-adhesion resistant ring when moving on an overhead wire to which the snow-adhesion resistant ring is mounted, easily transporting, and further protecting a main part.SOLUTION: A hanging sheave 1 is configured to be able to be hung from an overhead ground wire 10 and includes: four rollers 4 arranged side by side in an extension direction of the overhead ground wire 10; a support frame 5 for rotatably supporting each roller 4; and a crawler 6 wound around each roller 4. A cover frame 3 having a hook 3A, to which a pilot rope can be attached at one end, is rotatably supported on the support frame 5, and the cover frame 3 is in a first state P1 that is operable by the pilot rope by extending in a direction intersecting an arrangement direction of each roller 4 when rotated in one direction, while it is in a second state that is brought into an attitude extending to the arrangement direction of each roller 4 when rotated in the other direction, and each roller 4, the support frame 5, and the crawler 6 are located inside.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a suspension crane used when attaching a snow-repellent ring to an overhead wire.

Background Art

[0002] Conventionally, in order to prevent snow from adhering to and solidifying on overhead wires, it is known to attach a large number of snow-repellent rings to these overhead wires at predetermined intervals. The work of attaching the snow-repellent rings to the overhead wires is generally carried out by an operator getting out onto the overhead wires. However, in the case of an overhead ground wire with a small diameter, it is dangerous for the operator to get out onto it and perform the work of attaching the snow-repellent rings. Therefore, after stretching a philistran rope for the operator to get out onto during work between the towers, the work of attaching the snow-repellent rings is carried out. Specifically, first, a pilot rope is attached to a suspension crane suspended from the overhead ground wire, and the pilot rope is spanned from one tower to the other tower by a self-propelled vehicle. Then, a philistran rope is connected to the pilot rope, and the pilot rope is further pulled from the other tower side to span and fix the philistran rope between the two towers. After that, the operator gets out onto the philistran rope and attaches each snow-repellent ring to the overhead ground wire. When the work of attaching the snow-repellent rings to the overhead ground wire is completed, the fixing of the philistran rope to the two towers is released. Then, while pulling the philistran rope from one tower side with the suspension crane suspended from the overhead ground wire, the philistran rope, the pilot rope, and the suspension crane are recovered while moving the suspension crane along the overhead ground wire to complete the work of attaching the snow-repellent rings to the overhead ground wire.

[0003] Incidentally, when finishing the installation work of the snow adhesion prevention ring on the overhead ground wire, the suspended crane to be recovered moves while being pulled by the pilot rope located below the overhead ground wire along the overhead ground wire after the snow adhesion prevention ring is installed. Therefore, when the roller part of the suspended crane crosses over the snow adhesion prevention ring, a concentrated force is applied to the snow adhesion prevention ring in the extending direction of the overhead ground wire. In particular, since the overhead ground wire between the iron towers has slack, when the suspended crane moves upward along the overhead ground wire in the latter half of the recovery operation compared to the first half of the recovery operation when the suspended crane moves downward along the overhead ground wire, a large force is applied to the snow adhesion prevention ring in the extending direction of the overhead ground wire. In the worst case, the attachment position of the snow adhesion prevention ring to the overhead ground wire may shift from the desired position, resulting in the inability to prevent snow adhesion.

[0004] To avoid this, for example, during the installation work of the snow adhesion prevention ring on the overhead ground wire, a crawler-type suspended crane such as those in Patent Document 1 and Patent Document 2 is adopted. When the suspended crane crosses over the snow adhesion prevention ring after installation, the crawler part, rather than the roller part, directly contacts the snow adhesion prevention ring. By doing so, the contact area between the suspended crane and the snow adhesion prevention ring when crossing over the snow adhesion prevention ring can be widened, and the force applied to the snow adhesion prevention ring can be dispersed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, if a crawler-type suspension crane such as those disclosed in Patent Document 1 or Patent Document 2 is adopted as the suspension crane used during the installation work of the snow accumulation prevention ring on the overhead ground wire, the entire suspension crane will become large-sized, making it difficult to carry and requiring a great deal of labor to transport the suspension crane to the work location on the iron tower. Also, when the entire suspension crane becomes large-sized, it is likely to come into contact with objects around it when transporting the suspension crane to the work location, and such contact may cause, for example, a malfunction in the main part of the suspension crane.

[0007] The present invention has been made in view of such points, and an object thereof is to provide a suspension crane that can prevent the attachment position of the snow accumulation prevention ring from shifting when moving on an overhead power line to which the snow accumulation prevention ring is attached, is easy to transport, and can further protect the main part.

Means for Solving the Problem

[0008] In order to achieve the above object, the present invention is characterized in that it is provided with a cover frame capable of covering the main part of the suspension crane, and the cover frame has a structure that can be switched between a state of covering the main part of the suspension crane and a state of being able to travel on the overhead power line.

[0009] Specifically, for a suspension crane that can be suspended on an overhead power line, the following measures are taken. That is, the suspension crane according to the first invention includes a plurality of rollers arranged in parallel in the extending direction of the overhead power line, a support frame that rotatably supports each of the rollers, a crawler that is wound around each of the rollers and can orbitally move on the overhead power line by the rotational movement of each of the rollers, and a cover frame that is rotatably supported by the support frame and has a rope attachment portion at one end, and when rotated in one direction, it extends in a direction intersecting the parallel arrangement direction of the rollers and becomes a first state operable by the rope, and when rotated in the other direction, it extends in the parallel arrangement direction of the rollers and the crawler, each of the rollers, and the support frame are in a second state located inside. In the suspension crane configured as described above, when the cover frame is in the first state, it acts so that the suspension crane can be suspended from the overhead wiring with a rope attached to the attachment portion and used. On the other hand, when the cover frame is in the second state, the suspension crane has a compact outer shape in a direction extending perpendicular to the parallel arrangement direction of each roller and in a direction extending perpendicular to the axial direction of each roller, and the cover frame acts to surround many regions of the crawler, each roller, and the support frame.

[0010] In the suspension crane of the second invention, in the first invention, the cover frame is annular, and when it is in the second state, it is configured to accommodate the crawler, each roller, and the support frame inside. In the suspension crane configured as described above, when the cover frame is in the second state, the cover frame acts to surround the crawler, each roller, and the support frame in an endless annular shape without gaps.

[0011] In the suspension crane of the third invention, in the second invention, the cover frame includes a pair of strip-shaped first frames that extend parallel to each other in the same direction and whose middle parts are respectively pivotally supported by the respective support frames, and a pair of plate-shaped second frames that bridge the one end edge parts and the other end edge parts of the respective first frames. The width dimensions of the first frames and the second frames are set to dimensions such that the crawler and each roller do not protrude from both opening portions of the cover frame in the second state. In the suspension crane configured as described above, the cover frame becomes an elongated rectangular frame shape, and it acts so that the outer shape in the axial direction of each roller in the suspension crane when the cover frame is in the second state becomes compact. Also, when the cover frame is in the second state, it acts so that all of the crawler and each roller are in a state of being located inside the cover frame.

[0012] In the suspension crane of the fourth invention, in any one of the first to third inventions, a gripable handle is attached to the other end of the cover frame. In the hanging wire vehicle configured as described above, when the operator switches the cover frame between the first state and the second state, the operator acts so as to be able to rotate the cover frame by gripping the handle. Further, when transporting the hanging wire vehicle, the operator acts so as to be able to carry the hanging wire vehicle in a state where the handle is gripped and the hanging wire vehicle is lifted up.

[0013] In the hanging wire vehicle according to the fifth invention, in the first invention, each of the rollers includes a pair of first rollers supported at each end of the support frame, and a second roller disposed between the two first rollers. The lower end of the second roller is set to be positioned below the lower ends of the two first rollers in a state where the two first rollers are arranged horizontally. In the hanging wire vehicle configured as described above, when traveling on the overhead wiring between the two towers of the hanging wire vehicle, when moving downward on the overhead wiring, the area spanned by the first roller and the second roller on the rear side in the traveling direction of the crawler travels while contacting the overhead wiring. On the other hand, when moving upward on the overhead wiring, it acts so as to switch to a state where the area spanned by the first roller and the second roller on the front side in the traveling direction of the crawler travels while contacting the overhead wiring.

Advantages of the Invention

[0014] In the suspension crane of the first invention, when the cover frame is in the first state, the suspension crane can be suspended from the overhead wiring with a rope attached to the attachment part and used, so it can be used as a suspension crane when attaching the anti - snow - accumulation ring to the overhead wiring. Therefore, when recovering the suspension crane after attaching the anti - snow - accumulation ring to the overhead wiring, when the suspension crane crosses the anti - snow - accumulation ring attached to the overhead wiring, the crawler part comes into contact with the anti - snow - accumulation ring, and the force applied to the anti - snow - accumulation ring is dispersed, preventing the attachment position of the anti - snow - accumulation ring to the overhead wiring from shifting. On the other hand, when the cover frame is in the second state, the suspension crane has a compact outer shape in a direction perpendicular to the parallel arrangement direction of each roller and in a direction perpendicular to the axial direction of each roller, and the cover frame surrounds many areas of the crawler, each roller, and the support frame, making it easy to handle and transport. Furthermore, it can protect the main part of the suspension crane during transportation.

[0015] In the suspension crane of the second invention, when the cover frame is in the second state, the cover frame annularly surrounds the main parts of the crawler, each roller, and the support frame without a break. Therefore, even if the suspension crane contacts an object around it during transportation, it is difficult for the object around it to directly contact the crawler, each roller, and the support frame, making it easier to further avoid damage and deformation in the main part of the suspension crane.

[0016] In the suspension crane of the third invention, since the cover frame is in the shape of an elongated rectangular frame, the outer shape of the suspension crane in the axial direction of each roller when the cover frame is in the second state becomes compact, further enhancing the ease of handling during transportation of the suspension crane. Also, when the cover frame is in the second state, all of the crawler and each roller are located inside the cover frame. Therefore, during transportation of the suspension crane, damage and deformation of the crawler and each roller of the suspension crane can be reliably avoided.

[0017] In the hoisting trolley of the fourth invention, when switching the cover frame between the first state and the second state, the operator can rotate the cover frame by gripping the handle. Therefore, the operation of switching between the first state and the second state of the hoisting trolley can be easily performed. Further, when transporting the hoisting trolley, the operator can carry it in a state of gripping the handle and lifting the hoisting trolley, so that it is easy to transport the hoisting trolley to the work place.

[0018] In the hoisting trolley of the fifth invention, when traveling on the overhead wiring between the two towers of the hoisting trolley, when moving in the downward direction on the overhead wiring, the area spanned by the first roller and the second roller on the rear side of the traveling direction in the crawler travels while contacting the overhead wiring, while when moving in the upward direction on the overhead wiring, it switches so that the area spanned by the first roller and the second roller on the front side of the traveling direction in the crawler travels while contacting the overhead wiring. Therefore, the traveling of the hoisting trolley in the area where the slack overhead wiring switches from the front half area to the rear half area becomes smooth, and the hoisting trolley can be made easy to travel on the overhead wiring.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Mode for Carrying Out the Invention

[0020] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiments is merely illustrative in nature.

Embodiment

[0021] FIGS. 1 and 2 show the suspension trolley 1 according to Embodiment 1 of the present invention. The suspension trolley 1 is used by being suspended from an overhead ground wire 10 when attaching a snow adhesion prevention ring 11 (see FIG. 6) to the overhead ground wire 10 (overhead wiring) spanned between towers (not shown), and includes a traveling body 2 used in a posture extending along the overhead ground wire 10 and a cover frame 3 having a rectangular frame shape.

[0022] The traveling body 2 includes four metal rollers 4 having a substantially disc shape, a metal support frame 5 having a thick and elongated substantially strip shape, and a rubber crawler 6 extending annularly.

[0023] As shown in FIG. 3, an annular concave groove portion 4a that is recessed in a substantially V-shaped cross section and extends annularly along the circumferential direction of the roller 4 is formed at the outer peripheral edge portion of each roller 4, and a shaft support hole 4b through which a first bolt 12 including a head portion 12a and a shaft portion 12b can be inserted is formed through the center of each roller 4.

[0024] As shown in FIG. 1, the two rollers 4 respectively disposed at one end and the other end of the traveling body 2 have a larger diameter than the two rollers 4 located in the central region of the traveling body 2. Hereinafter, for convenience, the two rollers 4 respectively disposed at one end and the other end of the traveling body 2 will be referred to as first rollers 4A, and the two rollers 4 located in the central region of the traveling body 2 will be referred to as second rollers 4B.

[0025] The two first rollers 4A and the two second rollers 4B are arranged in parallel with each other in the same horizontal direction with the same rotation axis center and are arranged side by side in the extending direction of the overhead ground wire 10. The lower end of each second roller 4B is arranged at the same position as the lower ends of the two first rollers 4A in a state where the two first rollers 4A are arranged horizontally.

[0026] The support frame 5 has a trapezoidal shape that is narrow in width vertically when viewed in the rotation axis direction of the roller 4, and a pair of them are arranged so as to sandwich each first roller 4A and each second roller 4B.

[0027] On the outer surface of each support frame 5, as shown in FIGS. 1 to 3, four first seat tapping holes 5a capable of accommodating the head 12a of the first bolt 12 or the first nut 13 are sequentially formed from one end side to the other end side of each support frame 5. At the center of each first seat tapping hole 5a, first mounting holes 5b corresponding to the shaft support holes 4b of each first roller 4A and each second roller 4B are formed through.

[0028] Also, on the inner surface of each support frame 5, as shown in FIG. 4, a second seat tapping hole 5c capable of accommodating the second nut 15 is formed at the central portion of each support frame 5. At the center of each second seat tapping hole 5c, a second mounting hole 5d through which the second bolt 14 composed of the head 14a and the shaft portion 14b can be inserted is formed through.

[0029] Both support frames 5, each first roller 4A, and each second roller 4B are assembled with four sets of first bolts 12 and first nuts 13. That is, both support frames 5 sandwich each first roller 4A and each second roller 4B such that the shaft support holes 4b of each first roller 4A and each second roller 4B respectively correspond to the first mounting holes 5b of each support frame 5. As shown in FIG. 3, the first nut 13 is screwed onto the shaft portion 12b of the first bolt 12 inserted through the first mounting hole 5b and the shaft support hole 4b through the other first seat tapping hole 5a, so that each first roller 4A and each second roller 4B are rotatably supported.

[0030] As shown in FIG. 3, the crawler 6 has a substantially V-shaped cross section, and an annular ridge portion 6a that protrudes inward of the crawler 6 and extends along the circumferential direction is provided on the inner peripheral surface of the crawler 6. The annular ridge portion 6a has a shape corresponding to the cross section of each annular concave groove portion 4a of the first roller 4A and the second roller 4B, and is wound around each of the first roller 4A and the second roller 4B.

[0031] On the outer peripheral surface of the annular ridge portion 6a, a guide groove portion 6b having a substantially trapezoidal cross section that is recessed inward of the annular ridge portion 6a and extends annularly along the circumferential direction is formed. As shown in FIG. 2, the guide groove portion 6b can be externally fitted to the overhead ground wire 10, and the crawler 6 can be moved around on the overhead ground wire 10 by the rotational operation of each of the first roller 4A and the second roller 4B.

[0032] As shown in FIGS. 1 and 2, the cover frame 3 forms a seamless ring shape, and includes a pair of strip-shaped first frames 7 that extend parallel to each other in the same direction, and a pair of plate-shaped second frames 8 that bridge the one end edges and the other end edges of the respective first frames 7.

[0033] On one longitudinal end side of the first frame 7, a passage portion 7a that is cut out across the entire region from one end to the other end in the width direction of the first frame 7 is formed, and the passage portion 7a is covered with an opening / closing door 7b having a rectangular plate shape corresponding to the space.

[0034] The opening / closing door 7b is rotatably supported by one side edge portion of the second frame 8. When rotated in one direction, the passage portion 7a is opened to enable the overhead ground wire 10 to be taken in and out between the inside and the outside of the cover frame 3. When rotated in the other direction, the passage portion 7a is closed to prevent the overhead ground wire 10 located inside the cover frame 3 from coming off the suspension trolley 1.

[0035] On the other longitudinal side of each first frame 7, a substantially square-shaped opening 7c is formed therethrough. Further, at the center of each first frame 7, as shown in FIG. 4, a through-hole 7d corresponding to the second mounting hole 5d of the support frame 5 is formed.

[0036] The traveling body 2 and the cover frame 3 are assembled with two sets of second bolts 14 and second nuts 15. That is, the cover frame 3 has one second nut 15 screwed to the shaft portion 14b of one second bolt 14 inserted through the through-hole 7d of one first frame 7 and the second mounting hole 5d of one support frame 5 via the second counterbore 5c, while the other second nut 15 is screwed to the shaft portion 14b of the other second bolt 14 inserted through the through-hole 7d of the other first frame 7 and the second mounting hole 5d of the other support frame 5 via the second counterbore 5c, so that it is pivotally supported by both support frames 5 rotatably.

[0037] At the center of the second frame 8 located at one longitudinal end of the cover frame 3, as shown in FIGS. 6 and 7, a hook 3A (mounting portion) to which a pilot rope 9 can be attached is provided.

[0038] The hook 3A includes a hook body 3a having a substantially C-shaped configuration and a detachment preventing member 3b provided at the open portion of the hook body 3a. The detachment preventing member 3b is pivotally supported at the base of the hook body 3a and, in a normal state, closes the open portion of the hook body 3a, and by rotating inside the hook body 3a, the pilot rope 9 can be inserted and removed between the inside and the outside of the hook body 3a through the open portion of the hook body 3a.

[0039] On the other hand, at the center of the second frame 8 located at the other longitudinal end of the cover frame 3, as shown in FIGS. 1 and 2, a handle 3B having a substantially U-shaped configuration that is wide in a side view is attached, and an operator can grip this handle 3B to operate or lift the cover frame 3.

[0040] When the cover frame 3 is rotated in one direction, as shown in FIG. 1, it assumes a posture extending in a direction intersecting the parallel arrangement direction of the rollers 4, that is, when the rollers 4 are arranged horizontally in parallel, it extends in the vertical direction and enters the first state P1 that can be operated by the pilot rope 9 attached to the hook 3A. On the other hand, when it is rotated in the other direction, as shown in FIG. 5, it assumes a posture extending in the parallel arrangement direction of the rollers 4 and enters the second state P2 in which the rollers 4, both support frames 5, and the crawler 6 are located inside.

[0041] The width dimensions of the first frame 7 and the second frame 8 in the cover frame 3 are set to dimensions such that the rollers 4 and the crawler 6 do not protrude from both opening portions of the cover frame 3 in the second state P2. That is, the cover frame 3 is configured to accommodate the rollers 4, both support frames 5, and the crawler 6 inside when it enters the second state P2.

[0042] In addition, as shown by the phantom line in FIG. 5, when the periphery of the cover frame 3 is surrounded by a rubber band 16 when the cover frame 3 is in the second state P2, it is possible to prevent the traveling body 2 from rotating and protruding from the inside of the cover frame 3 when the suspension crane 1 is being transported, making it easier to transport.

[0043] Next, regarding the suspension crane 1 of the first embodiment of the present invention used when stretching a philistran rope between towers in order to attach the snow adhesion prevention ring 11 to the overhead ground wire 10, the operation of recovering the suspension crane 1 after the attachment operation of the snow adhesion prevention ring 11 will be described in detail.

[0044] The operator pulls the pilot rope 9 to pull the suspension crane 1 via the pilot rope 9 by pulling the Philly strand rope from one side of the iron tower. Then, since the overhead ground wire 10 is slack between the iron towers, in the first half of the recovery operation of the suspension crane 1, as shown in Fig. 6, the suspension crane 1 moves downward on the overhead ground wire 10 by the circumferential movement of the crawler 6 due to the rotational movement of each roller 4. At this time, a large number of snow-sticking prevention rings 11 are attached to the overhead ground wire 10 at predetermined intervals, and when the traveling body 2 crosses each snow-sticking prevention ring 11, a force is applied to each snow-sticking prevention ring 11 in the extension direction of the overhead ground wire 10. However, in the suspension crane 1 of Embodiment 1 of the present invention, since the crawler 6 comes into contact with each snow-sticking prevention ring 11, the force applied to each snow-sticking prevention ring 11 is dispersed. Therefore, it is possible to prevent the attachment position of the snow-sticking prevention ring 11 to the overhead ground wire 10 from shifting.

[0045] Furthermore, when the recovery operation of the suspension crane 1 is continued, in the second half of the recovery operation of the suspension crane 1, as shown in Fig. 7, the suspension crane 1 moves upward on the overhead ground wire 10 by the circumferential movement of the crawler 6 due to the rotational movement of each roller 4. At this time, while pulling the pilot rope 9 obliquely downward on one side of the iron tower, since the traveling body 2 moves upward along the overhead ground wire 10, the force applied to each snow-sticking prevention ring 11 from the suspension crane 1 becomes larger than in the first half of the recovery operation. However, in the suspension crane 1 of Embodiment 1 of the present invention, since the crawler 6 comes into contact with each snow-sticking prevention ring 11 and the force applied to each snow-sticking prevention ring 11 is dispersed, it is possible to prevent the attachment position of the snow-sticking prevention ring 11 to the overhead ground wire 10 from shifting even in the second half of the recovery operation of the suspension crane 1.

[0046] As described above, according to the first embodiment of the present invention, as shown in FIG. 1, when the cover frame 3 is in the first state P1, the hoisting trolley 1 can be suspended from the overhead ground wire 10 with the pilot rope 9 attached to the hook 3A, so that it can be used. Therefore, when the hoisting trolley 1 is recovered after the attachment operation of the snow arrest ring 11 to the overhead ground wire 10, when the hoisting trolley 1 crosses the snow arrest ring 11 attached to the overhead ground wire 10, the crawler 6 comes into contact with the snow arrest ring 11, and the force applied to the snow arrest ring 11 is dispersed, preventing the attachment position of the snow arrest ring 11 to the overhead ground wire 10 from shifting.

[0047] On the other hand, as shown in FIG. 5, when the cover frame 3 is in the second state P2, the hoisting trolley 1 has a compact outer shape in a direction perpendicular to the parallel arrangement direction of the rollers 4 and in a direction perpendicular to the axial direction of the rollers 4. At the same time, since the cover frame 3 surrounds many regions of the rollers 4, the support frame 5, and the crawler 6, it becomes easier to handle and transport. Furthermore, the main part of the hoisting trolley 1 can be protected during transportation.

[0048] In addition, since the cover frame 3 is annular, when it is in the second state P2, it surrounds the main parts of the rollers 4, the support frame 5, and the crawler 6 in an annular shape without interruption. Therefore, even if the hoisting trolley 1 contacts an object around it during transportation, it is difficult for the object around it to directly contact the rollers 4, the support frame 5, and the crawler 6, making it easier to further avoid damage and deformation in the main part of the hoisting trolley 1.

[0049] Further, the cover frame 3 is formed of a pair of strip-shaped first frames 7 extending in parallel in the same direction, and a pair of plate-shaped second frames 8 that bridge between one end edge and the other end edge of each of the first frames 7, respectively, forming an elongated rectangular frame shape. Therefore, when the cover frame 3 is in the second state P2, the outer shape in the axial direction of each roller 4 in the hoist trolley 1 becomes compact, and the ease of handling during the transportation of the hoist trolley 1 can be further enhanced.

[0050] Moreover, the width dimensions of the first frame 7 and the second frame 8 in the cover frame 3 are set such that the rollers 4 and the crawlers 6 do not protrude from both open portions of the cover frame 3 in the second state P2. Therefore, when the cover frame 3 is in the second state P2, all of the rollers 4 and the crawlers 6 are positioned inside the cover frame 3. Accordingly, during the transportation of the hoist trolley 1, damage and deformation of the rollers 4 and the crawlers 6 of the hoist trolley 1 can be reliably avoided.

[0051] Furthermore, when switching the cover frame 3 between the first state P1 and the second state P2, the operator can hold the handle 3B and rotate the cover frame 3. Therefore, the operation of switching the hoist trolley 1 between the first state P1 and the second state P2 can be easily performed. Also, when transporting the hoist trolley 1, the operator can hold the handle 3B and carry the hoist trolley 1 in a lifted state, making it easier to transport the hoist trolley 1 to the work location.

[0052] In addition, in the first embodiment of the present invention, the crawler 6 is circulated by two first rollers 4A and two second rollers 4B, but a configuration in which the crawler 6 is circulated only by two first rollers 4A may be used, or a configuration in which three or more first rollers 4A are arranged to circulate the crawler 6 may be used. Also, one second roller 4B may be arranged between two first rollers 4A, or three or more second rollers 4B may be arranged.

Embodiment

[0053] FIG. 8 shows the suspension trolley 1 of Example 2 of the present invention. In this Example 2, since a part of the structure of the traveling body 2 is different from that of Example 1, the same reference numerals are given to the same parts as in Example 1, and only the different parts will be described hereinafter.

[0054] In Example 2, one second roller 4B is disposed between the two first rollers 4A, and its lower end is set to be positioned below the lower ends of the two first rollers 4A in a state where the two first rollers 4A are arranged horizontally. Further, the support frame 5 of Example 2 has a trapezoidal shape that is wider than that of Example 1.

[0055] Next, regarding the suspension trolley 1 of Example 2 of the present invention used when stretching a philistran rope between towers to attach the snow adhesion prevention ring 11 to the overhead ground wire 10, the operation of recovering the suspension trolley 1 after the attachment operation of the snow adhesion prevention ring 11 will be described in detail.

[0056] An operator pulls the suspension trolley 1 via the pilot rope 9 by pulling the philistran rope from one tower side. Then, since the overhead ground wire 10 is slack between the towers, in the first half of the recovery operation, as shown in FIG. 9, the suspension trolley 1 moves downward on the overhead ground wire 10 by the circumferential movement operation of the crawler 6 due to the rotation operation of each roller 4. At this time, in the suspension trolley 1 of Example 2, the area spanned by the first roller 4A and the second roller 4B on the rear side in the traveling direction of the crawler 6 travels while contacting the overhead ground wire 10. Also in the suspension trolley 1 of Example 2, when the traveling body 2 gets over each snow adhesion prevention ring 11, the crawler 6 contacts each snow adhesion prevention ring 11, so that the force applied to each snow adhesion prevention ring 11 is dispersed, and it is possible to prevent the attachment position of the snow adhesion prevention ring 11 to the overhead ground wire 10 from shifting.

[0057] Furthermore, when the recovery operation of the suspension crane 1 is continued, in the latter half of the recovery operation of the suspension crane 1, as shown in FIG. 10, the suspension crane 1 moves in an upward direction on the overhead ground wire 10 by the circumferential movement operation of the crawler 6 due to the rotation operation of each roller 4. At this time, in the suspension crane 1 of the second embodiment, it is switched so that the area spanned by the first roller 4A and the second roller 4B on the front side in the traveling direction of the crawler 6 travels while contacting the overhead ground wire 10. Also in the suspension crane 1 of the second embodiment, the force applied from the suspension crane 1 to each snow-sticking prevention ring 11 becomes larger than that in the first half of the recovery operation of the suspension crane 1. However, since the crawler 6 contacts each snow-sticking prevention ring 11 and the force applied to each snow-sticking prevention ring 11 is dispersed, it is possible to prevent the attachment position of the snow-sticking prevention ring 11 with respect to the overhead ground wire 10 from shifting even in the latter half of the recovery operation of the suspension crane 1.

[0058] As described above, according to the second embodiment of the present invention, when the suspension crane 1 is recovered, the traveling of the suspension crane 1 in the region where the front half region of the slack overhead ground wire 10 switches to the rear half region becomes smooth, and the suspension crane 1 can be made easy to travel on the overhead ground wire 10.

[0059] In the second embodiment of the present invention, the crawler 6 is moved in a circumferential direction by two first rollers 4A and one second roller 4B. However, a configuration in which two or more second rollers 4B are arranged between the two first rollers 4A may also be used.

[0060] Also, in the first and second embodiments of the present invention, when the cover frame 3 is in the second state P2, the entire traveling body 2 is housed inside the cover frame 3. However, any structure may be used as long as the main part is housed, and a structure in which a part of the outer periphery of the roller 4 or a part of the support frame 5 protrudes from the cover frame 3 may also be used.

[0061] Also, in the first and second embodiments of the present invention, the cover frame 3 forms a seamless ring shape. However, the present invention is not limited to this, and a structure in which a part is cut out may also be used. That is, when the cover frame 3 is in the second state P2, any structure may be used as long as it can surround and protect the main part of the traveling body 2.

[0062] In addition, in the first and second embodiments of the present invention, the pilot rope 9 is attached to the hook 3A, but it may be attached to an endless suspension bolt without a break. Further, the opening 7c formed in the cover frame 3 may be formed in other regions of the cover frame 3 to reduce the weight of the entire suspension pulley 1.

[0063] In addition, in the first and second embodiments of the present invention, the pilot rope 9 is attached to the hook 3A and the suspension pulley 1 is used, but other ropes can be attached to the hook 3A and used.

[0064] Note that the suspension pulley 1 of the first and second embodiments of the present invention is suspended from the overhead ground wire 10 and used, but it can also be suspended from other overhead wirings and used.

Industrial Applicability

[0065] The present invention is suitable for a suspension pulley used when attaching a snow adhesion prevention ring to an overhead wiring.

Explanation of Reference Numerals

[0066] 1... Suspension pulley, 2... Traveling body, 3... Cover frame, 3A... Hook, 3B... Handle, 3a... Hook body, 3b... Disengagement prevention member, 4... Roller, 4A... First roller, 4B... Second roller, 4a... Annular concave groove portion, 4b... Axle support hole, 5... Support frame, 5a... First seat boring hole, 5b... First mounting hole, 5c... Second seat boring hole, 5d... Second mounting hole, 6... Crawler, 6a... Annular protrusion portion, 6b... Guide groove portion, 7... First frame, 7a... Passage portion, 7b... Opening / closing door, 7c... Opening, 7d... Through hole, 8... Second frame, 9... Pilot rope, 10... Overhead ground wire, 11... Snow adhesion prevention ring, 12... First bolt, 12a... Head, 12b... Shaft portion, 13... First nut, 14... Second bolt, 14a... Head, 14b... Shaft portion, 15... Second nut, 16... Band, P1... First state, P2... Second state

Claims

1. An overhead crane that can be suspended from overhead wiring, comprising: a plurality of rollers arranged side by side in the extending direction of the overhead wiring; a support frame that rotatably supports each of the rollers; a crawler wound around each of the rollers and capable of orbiting on the overhead wiring by the rotational movement of each of the rollers; a cover frame pivotally supported by the support frame, having a rope attachment portion at one end, and when rotated in one direction, extending in a direction intersecting the side-by-side direction of the rollers and being in a first state operable by the rope, and when rotated in the other direction, assuming a posture extending in the side-by-side direction of the rollers and being in a second state where the crawler, each of the rollers, and the support frame are located inside.

2. The overhead crane according to Claim 1, wherein the cover frame is annular and is configured to accommodate the crawler, each of the rollers, and the support frame inside when in the second state.

3. The overhead crane according to Claim 2, wherein the cover frame includes a pair of strip-shaped first frames extending parallel to each other in the same direction and pivotally supported by each of the support frames at an intermediate portion, and a pair of plate-shaped second frames bridging the one end edges and the other end edges of the respective first frames, and the width dimensions of the first frame and the second frame are set such that the crawler and each of the rollers do not protrude from both opening portions of the cover frame in the second state.

4. The overhead crane according to any one of Claims 1 to 3, wherein a gripable handle is attached to the other end of the cover frame.

5. The overhead crane according to Claim 1, wherein each of the rollers is composed of a pair of first rollers supported at each end of the support frame and a second roller disposed between the two first rollers, and the lower end of the second roller is set to be positioned below the lower ends of the two first rollers in a state where the two first rollers are arranged horizontally side by side.

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