Fall prevention equipment and support columns

Abstract

To provide fall preventive equipment capable of relaxing sudden tension applied to a main rope and inhibiting breakage of a support column, and a support column capable of relaxing tension applied to a main rope.SOLUTION: One aspect of the present invention is fall preventive equipment that is provided with a main rope connected to a worker through a safety belt, and a support column for stretching this main rope, and is temporarily constructed at a boom or jib to prevent fall of the worker, in which at least a part of the support column is elastically deformed when tension is applied to the main rope. Another aspect of the present invention is a support column for fall preventive equipment for stretching a main rope connected to a worker through a safety belt to prevent fall of the worker, in which at least a part of the support column is elastically deformed when tension is applied to the main rope.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a fall prevention facility and a support column.

Background Art

[0002] As construction machinery, a crane or the like having a boom, a jib, etc. on a slewing body is known. In a large luffing jib crane, a tower crane, etc., the boom and the jib may be composed of a plurality of divided bodies. The plurality of divided bodies are assembled to the boom and the jib at the construction site, and are disassembled at the site when the construction is completed.

[0003] In the assembly work and disassembly work of the boom and the jib, an operator may work on the boom, the jib, or these divided bodies (hereinafter referred to as "boom etc."). A fall prevention facility for preventing the operator from falling from the boom etc. may be temporarily installed on the boom etc. during work.

[0004] As such a fall prevention facility, a safety fence including a cable body (main cable) provided in parallel to the upper surface of the boom and a plurality of rod bodies (support columns) over which the cable body is spanned is known (Japanese Unexamined Patent Application Publication No. 2017-043458). Since the plurality of rod bodies are arranged on the boom so as to be able to be inverted, it is said that the safety fence can be easily assembled.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Generally, the above-mentioned cable body serves as a handrail to prevent the operator from falling, and is connected to the above-mentioned operator with a rope or the like called a safety belt as the main cable. Therefore, even if the operator falls from the above-mentioned boom, it is possible to suppress the collision with the ground, floor, etc. That is, it is expected that the fallen operator will be protected from colliding with the above-mentioned ground or the like by being supported by the above-mentioned cable body and the above-mentioned rod body via the above-mentioned safety belt.

[0007] In the case of the operator's fall, the above-mentioned cable body and the above-mentioned rod body propagated from this are subject to a sudden impact generated by the operator's fall, and there is a risk that this impact may damage the above-mentioned rod body. That is, since the above-mentioned cable body is connected to the upper end of the above-mentioned rod body, the moment force of the height (length) of the above-mentioned rod body acts on the base end portion of the above-mentioned rod body (the mounting portion to the above-mentioned boom), resulting in a greater impact and an instantaneous tension acting on the above-mentioned cable body, and a force exceeding the rigidity force acting on the above-mentioned rod body, which may damage the above-mentioned rod body.

[0008] Therefore, the inventor of the present invention has intensively studied to mitigate the sudden impact caused by the operator's fall or the like, and completed the present invention. An object of the present invention is to provide a fall prevention facility that can mitigate the sudden tension applied to the main cable and suppress damage to the support column, and a support column that can mitigate the tension applied to the main cable.

Means for Solving the Problems

[0009] One aspect of the present invention made to solve the above problems includes a main cable connected to an operator via a safety belt, and a support column for stretching this main cable, and is a fall prevention facility temporarily installed on a boom or a jib to prevent the operator from falling, and at least a part of the support column elastically deforms when tension is applied to the main cable.

[0010] The fall prevention facility can mitigate the sudden tension even if sudden tension is generated in the main cable by elastically deforming a part of the support column that supports the main cable, and can suppress damage to the support column or the like.

[0011] Another aspect of the present invention is a support column for a fall prevention facility that stretches a main rope connected to a worker via a safety belt, and at least a part of the column elastically deforms when tension is applied to the main rope.

[0012] Since a part of the column elastically deforms, it can relieve the sudden tension applied to the main rope and prevent damage or the like.

Advantages of the Invention

[0013] The fall prevention facility of the present invention can relieve the sudden tension applied to the main rope and prevent the support column from being damaged or the like. Further, the support column of the present invention can relieve the sudden tension applied to the main rope.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0015] One aspect of the present invention includes a main rope connected to a worker via a safety belt and a support column for stretching the main rope, and is a fall prevention facility temporarily installed on a boom or jib to prevent the worker from falling, and at least a part of the support column elastically deforms when tension is applied to the main rope.

[0016] Due to a part of the support column supporting the main rope elastically deforming, for example, sudden tension applied to the main rope due to the impact of the worker's fall can be relieved, so that damage or the like to the support column can be suppressed.

[0017] It is preferable to have a stopper that regulates the amount of elastic deformation of the above-mentioned support column. By doing so, it is possible to prevent the above-mentioned support column from deforming too much, so that damage to the above-mentioned support column can be effectively suppressed.

[0018] The above-mentioned support column preferably has a lower member erected on the above-mentioned boom or jib, an upper member disposed above the lower member and supporting the above-mentioned main rope, and an elastically deformable connecting member connecting the above-mentioned lower member and the above-mentioned upper member. By doing so, the connecting member that elastically deforms can relieve the tension applied to the above-mentioned main rope.

[0019] It includes a lower stopper having a lower protruding portion protruding above the above-mentioned lower member, and an upper stopper protruding below the above-mentioned upper member and having an upper protruding portion facing the above-mentioned lower protruding portion. In the non-elastically deformed state of the above-mentioned connecting member, the above-mentioned lower protruding portion and the above-mentioned upper protruding portion are separated, and in the elastically deformed state of the above-mentioned connecting member, the above-mentioned lower protruding portion and the above-mentioned upper protruding portion come into contact to regulate the amount of elastic deformation of the above-mentioned support column. By doing so, it is possible to more effectively prevent the above-mentioned support column from being damaged or the like.

[0020] Another aspect of the present invention is a support column for a fall prevention facility that stretches a main rope connected to a worker via a safety belt to prevent the worker from falling, and at least a part of it elastically deforms when tension is applied to the above-mentioned main rope.

[0021] Since a part of the support column elastically deforms, it is possible to relieve the tension applied to the above-mentioned main rope and prevent damage or the like.

[0022] [Details of the mode for carrying out the invention] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. The drawings are for explaining the present invention, and the shape, scale, etc. of each component (each member) may be different from the actual ones.

[0023] [Crane] The fall prevention equipment of the present invention is temporarily installed on the boom, jib, etc. of a crane. Specifically, it is used for assembly work, disassembly work, etc. of the above boom, jib, etc. The above crane is, for example, a luffing jib crane 1 (hereinafter referred to as "crane 1") mainly including a boom 2, a jib 3, an upper slewing body 4, and a lower traveling body 5 that rotatably supports the upper slewing body 4 as shown in FIG. 1.

[0024] The lower traveling body 5 has a pair of crawlers, etc. as a traveling device, and can travel in any direction to move the crane 1. The upper slewing body 4 is rotatably mounted on the lower traveling body 5, and has a cab for the operator, a boom winch for pitching the boom 2, a jib winch for pitching the jib 3, a hoisting winch for sending out and winding up a hoisting cable suspended from the tip of the jib 3, etc. Note that "pitching" means that the boom 2 and the jib 3 swing between an upright state and a fallen state.

[0025] 〔Boom〕 The base end of the boom 2 is connected to the upper slewing body 4 and pitches in a direction perpendicular to the rotation plane of the upper slewing body 4. The boom 2 is connected to the jib 3 on the tip side, and has an upper boom 21 having a tapered shape, an intermediate boom 22 arranged at the center in the longitudinal direction, and a lower boom 23 connected to the upper slewing body 4 and having a tapered shape. The intermediate boom may be configured to be divisible into a plurality in the longitudinal direction.

[0026] The upper boom 21, the lower boom 23, and the intermediate boom 22 are formed in a substantially square tube shape and have a lattice structure. The lattice structure includes four boom main girders (struts or main columns) arranged so as to be located at the vertices of a virtual square in a cross-sectional view perpendicular to the longitudinal direction, and a plurality of boom supplementary girders (lattices or diagonal members) arranged to form a plurality of triangles, quadrilaterals, etc. connecting between the adjacent boom main girders with the boom main girders as the bases. The upper boom 21 and the lower boom 23 may be plate-shaped reinforcing members instead of the plurality of boom supplementary girders. The upper boom 21, the lower boom 23, and the intermediate boom 22 are assembled into one boom 2 by connecting the ends of the boom main girders.

[0027] [Jib] The jib 3 has its proximal end connected to the tip of the boom 2. Similar to the boom 2, the jib 3 can pitch vertically with respect to the rotating surface of the upper slewing body 4 and suspends the hoisting cable 6 at its tip. The jib 3 includes a lower jib 31 connected to the boom 2, an intermediate jib 32 forming a straight cylindrical portion at the longitudinal center, and an upper jib 33 on the tip side. The lower jib 31 and the upper jib 33 are tapered.

[0028] The lower jib 31, the intermediate jib 32, and the upper jib 33 are formed in a substantially square tube shape and have a lattice structure, similar to the boom 2. The lattice structure includes four main jib members arranged to be located at the vertices of a virtual square in a cross-sectional view perpendicular to the longitudinal direction, and a plurality of auxiliary jib members arranged to form a plurality of triangles, quadrilaterals, etc. connecting between adjacent main jib members with the main jib members as the bases. The lower jib 31 and the upper jib 33 may be plate-shaped reinforcing members instead of the plurality of auxiliary jib members. The lower jib 31, the intermediate jib 32, and the upper jib 33 are assembled into one jib 3 by connecting the ends of the main jib members to each other.

[0029] [Falling prevention equipment] The falling prevention equipment of the present invention is used for the assembly work and disassembly work of the boom 2 or the jib 3. As an example, FIG. 2 shows the falling prevention equipment 10 mounted on the intermediate boom 22. The falling prevention equipment 10 is mounted on the upper surface of the intermediate boom 22. Here, the "upper surface" means the surface composed of a pair of main girders 221 on the side opposite to the side in contact with the ground, etc. of the intermediate boom 22 placed such that the longitudinal direction is substantially parallel to the ground, floor, etc.

[0030] Specifically, the fall prevention facility 10 includes a main rope 11 provided parallel to the upper surface of the intermediate boom 22 and connected to an operator via a safety belt (not shown), and a support column 12 that supports the main rope 11. The main rope 11 is a string-like member such as a wire rope or a chain, and the support column 12 is a columnar member that supports the main rope 11 so as to be separated from the upper surface of the intermediate boom 22 by a predetermined height. The lower end of the support column 12 is fixed by a U-bolt 13 that fits over the main girder 221 of the intermediate boom 22, and the upper end locks one end of the main rope 11. In this embodiment, the support columns 12 are arranged close to both ends in the longitudinal direction of the intermediate boom 22. The pair of support columns 12 may be provided on one of the pair of main girders 221 that constitute the upper surface of the intermediate boom 22, or may be provided on each of the pair of main girders 221. The support column 12 may be fixed to a secondary girder of the intermediate boom 22.

[0031] <Support column> As shown in FIGS. 3 and 4, the support column 12 of this embodiment has a lower member 121 arranged on the intermediate boom 22, an upper member 122 arranged above the lower member 121, and a connecting member 123 that connects the lower member 121 and the upper member 122 and is elastically deformable. The support column 12 also has a stopper 124 that regulates the amount of elastic deformation of the support column 12.

[0032] (Lower member) The lower member 121 has a lower support column 1211 and a mounting portion 1212 provided at the lower part of the lower support column 1211. The mounting portion 1212 includes a base plate 1212a and a holding portion 1212b. The base plate 1212a is substantially plate-shaped, a part of one surface abuts against the main girder 221 to which the support column 12 is mounted, and has a through hole (not shown) for inserting the end of the U-shaped bolt 13. The end of the U-shaped bolt 13 inserted through this through hole is fixed with a nut 14. The holding portion 1212b is a pair of substantially plate-shaped members, is arranged perpendicular to the other surface of the base plate 1212a, and holds the lower support column 1211. The lower support column 1211 is held by the holding portion 1212b so that its longitudinal direction is substantially perpendicular to the surface of the base plate 1212a. The lower support column 1211 is a columnar or cylindrical member with a substantially circular or substantially rectangular cross section, and is formed of, for example, iron, aluminum, stainless steel, etc.

[0033] (Upper member) The upper member 122 has an upper support column 1221 and a locking portion 1222 provided at the upper part of the upper support column 1221. The locking member 1222 includes a groove 1222a formed at the upper end to be substantially parallel to the main girder 221, and a shaft 1222b arranged in the groove 1222a and having an axial direction substantially orthogonal to the longitudinal direction of the main girder 221 in plan view. The shaft 1222b locks the end of the main cable 11. The end of the main cable 11 may be locked to the shaft 1222b by bundling, or a hook may be provided at the end of the main cable 11 and this hook may be locked to the shaft 1222b. The main cable 11 is preferably stretched between the pair of support columns 12 so that a predetermined tension is applied. The upper support column 1221 is supported by the lower support column 1211 via a connecting member 123 described later. The upper support column 1221 is formed with the same shape and material as the lower support column 1211. The bending rigidity of the lower support column 1211 and the bending rigidity of the upper support column 1221 are substantially the same. The upper support column 1221 and the lower support column 1211 may be formed with different shapes and materials.

[0034] (Connecting member) The connecting member 123 connects the lower member 121 and the upper member 122. The connecting member 123 is a substantially plate-shaped member that can be elastically deformed. The material of the connecting member 123 is not particularly limited, and for example, it is formed of iron, stainless steel, or the like. Specifically, the substantially plate-shaped connecting member 123 is provided such that its front and back surfaces are orthogonal to the longitudinal direction of the main girder 221. In other words, the thickness direction of the substantially plate-shaped connecting member 123 and the longitudinal direction of the main girder 221 are substantially parallel. The bending rigidity of the connecting member 123 in the longitudinal direction of the main girder 221 is relatively lower than the bending rigidities of the lower support column 1211 and the upper support column 1221. The connecting member 123 has the static rigidity necessary to support the upper member 122.

[0035] The method of connecting the connecting member 123 to the lower member 121 and the upper member 122 is not particularly limited. For example, grooves substantially the same as the thickness of the connecting member 123 are formed at the upper end of the lower member 121 and the lower end of the upper member 122, the connecting member 123 is fitted into these grooves, and fixed by adhesion, welding, or the like. Alternatively, the connecting member 123 may be fastened to the lower member 121 and the upper member 122 with fasteners such as bolts and nuts. By doing so, the support column 12 can be assembled and disassembled, and the connecting member 123 can be made replaceable.

[0036] The height (length) of the lower member 121 is preferably 1 / 2 or more of the total height (total length) of the support column 12. In other words, the height at which the connecting member 123 is disposed is preferably 1 / 2 or more of the total height of the support column 12. If the height of the lower member 121 is less than the above lower limit, the length of the upper support column 1221 becomes relatively long and the weight of the upper member 122 increases, resulting in the need to increase the static rigidity of the connecting member 123. As a result, it may become difficult to make the bending rigidity of the connecting member 123 relatively lower than the bending rigidities of the lower support column 1211 and the upper support column 1221. Note that the "height of the lower member 121" means the length from the one surface of the base plate 1212a to the upper end of the lower support column 1211. Also, the "total height of the support column 12" means the length from the one surface of the base plate 1212a to the upper end of the locking portion 1222.

[0037] Since the bending rigidity of the connecting member 123 in the longitudinal direction of the main girder 221 is lower than the bending rigidities of the lower strut 1211 and the upper strut 1221, when tension is applied to the main cable 11, the connecting member 123 deforms. The connecting member 123 elastically deforms until material yield is reached. That is, by having the strut 12 with the connecting member, until reaching the above-mentioned material yield, the upper strut 1221 can swing in the longitudinal direction. When tension is applied to the main cable 11 through the safety belt due to a worker falling from above the intermediate boom 22 or the like, the upper member 122 of the strut 12 that locks the end of the main cable 11 falls inward (the side where the main cable 11 is supported in the longitudinal direction) due to the elastic deformation of the connecting member 123. In this way, the strut 12 can relieve the tension applied to the main cable 11.

[0038] (Stopper) The strut 12 of the present embodiment has a stopper 124 that regulates the amount of elastic deformation of the connecting member 123. The stopper 124 includes a lower stopper 124a and an upper stopper 124b. In the present embodiment, the lower stopper 124a and the upper stopper 124b are columnar members having a substantially rectangular cross section. The lower stopper 124a and the upper stopper 124b are formed of, for example, iron, aluminum, stainless steel, or the like. The cross sections of the lower stopper 124a and the upper stopper 124b are not limited to being substantially rectangular, and may be substantially circular or the like.

[0039] The lower stopper 124a has a lower protruding portion that protrudes upward from the lower member 121. Specifically, the lower stopper 124a is disposed on the inner side surface at the upper part of the lower member 121. The longitudinal direction of the lower stopper 124a is arranged substantially parallel to the longitudinal direction of the lower member 121. The lower stopper 124a has, as the lower protruding portion, an upper end that protrudes upward from the upper end of the lower member 121.

[0040] The upper stopper 124b protrudes downward from the lower end of the upper member 122 and has an upper protruding portion facing the lower protruding portion. Specifically, the upper stopper 124b is arranged on the inner side surface at the lower part of the upper member 122. The longitudinal direction of the upper stopper 124b is arranged substantially parallel to the longitudinal direction of the upper member 122. The upper stopper 124b, as the upper protruding portion, has a lower end protruding downward from the lower end of the upper member 122 and faces the upper end (the lower protruding portion) of the lower stopper 124a.

[0041] The upper end of the lower stopper 124a and the lower end of the upper stopper 124b are separated in the non-elastic deformation state of the connecting member 123. That is, the upper end of the lower stopper 124a and the lower end of the upper stopper 124b are separated in a state where no tension is applied to the main cable 11. When tension is applied to the main cable 11, the upper member 122 of the support column 12 falls inward due to the elastic deformation of the connecting member 123. In this elastic deformation state of the connecting member 123, the lower protruding portion and the upper protruding portion come into contact. That is, the upper end of the lower stopper 124a provided on the inner side of the support column 12 and the lower end of the upper stopper 124b come into contact. For this reason, the amount of elastic deformation of the connecting member 123 is restricted. In other words, the upper member 122 cannot fall beyond a predetermined angle by the stopper 124. By making the upper end of the lower stopper 124a and the lower end of the upper stopper 124b come into contact before the connecting member 123 reaches material yield, it is possible to suppress the connecting member 123 from deforming beyond material yield. Further, since the stopper 124 becomes a part of the support column 12 when the upper end of the lower stopper 124a and the lower end of the upper stopper 124b come into contact, the rigidity as the support column 12 can be improved.

[0042] The separation distance between the upper end of the lower stopper 124a and the lower end of the upper stopper 124b is not particularly limited and is set according to the shape and material of the connecting member 123, the overall height of the support column 12, the height of the lower member 121, and the like.

[0043] [Advantages] When the fall prevention device 1 is in operation, the connecting member 123 of the support column 12 undergoes elastic deformation, causing the upper member 122 to tilt inward. This can relieve the tension applied to the main cable 11 and prevent damage or the like.

[0044] [Other Embodiments] The above embodiments do not limit the configuration of the present invention. Therefore, based on the description in this specification and common technical knowledge, components of each part of the above embodiments can be omitted, replaced, or added, and all of them should be construed as belonging to the scope of the present invention.

[0045] In the above embodiments, the fall prevention device is described as being provided on the intermediate boom. However, it is not limited to the intermediate boom. The fall prevention device may be provided on the upper boom, lower boom, upper jib, intermediate jib, lower jib, or other members such as a strut tower. Also, the member on which the fall prevention device is provided may not have a lattice structure.

[0046] Furthermore, the fall prevention device may be temporarily installed on something other than construction machinery, and the use of the support column is not limited to construction machinery.

[0047] The fixing method for the lower end of the support column is not limited to a U-bolt, and it may be fixed by other known methods.

[0048] For the lower support column and the upper support column of the support column, H-shaped steel, I-shaped steel, channel steel, angle steel, etc. may be used.

[0049] In the above embodiments, the configuration is described with one connecting member disposed between the lower member and the upper member. However, two or more connecting members may be disposed between the lower member and the upper member, or a plurality of connecting members may be arranged in the longitudinal direction of the support column. Also, although the connecting member is described as being a substantially plate-shaped one formed of iron or the like, the material and shape are not particularly limited.

[0050] Although the support column has been described as having substantially the same bending rigidity as that of the lower support column and the upper support column, the bending rigidity of the lower support column may be greater than that of the upper support column. When tension is applied to the main rope, the moment received by the support column increases towards the lower side of the support column. Therefore, by making the bending rigidity of the lower support column greater than that of the upper support column, it is possible to further suppress damage to the support column.

[0051] The lower support column may have a larger cross-sectional area at the lower side than at the upper side. For example, the lower support column may have a portion where the cross-sectional area gradually increases downward. By doing so, the bending rigidity of the lower support column can be made greater than that of the upper support column.

[0052] In the above-described embodiment, the stopper has been described as regulating the amount of elastic deformation of the connecting member. However, the stopper may be configured to regulate the amount of plastic deformation of the connecting member beyond elastic deformation. In this case, the connecting member is preferably detachably attached to the lower support column and the upper support column and can be easily replaced.

Industrial Applicability

[0053] The fall prevention equipment according to the present invention can be suitably used, for example, in assembly work and disassembly work of large luffing jib cranes and the like.

Explanation of Signs

[0054] 1 Crane (Luffing Jib Crane) 2 Boom 21 Upper Boom 22 Intermediate Boom 221 Main Girder 23 Lower Boom 3 Jib 31 Lower Jib 32 Intermediate Jib 33 Upper Jib 4 Upper Slewing Body 5 Lower Traveling Body 6 Hoisting Cable 10 Fall prevention equipment 11 Parent rope 12 Support pillar 121 Lower member 1211 Lower support pillar 1212 Mounting part 1212a Base plate 1212b Holding part 122 Upper member 1221 Upper support pillar 1222 Locking part 1222a Groove 1222b Shaft 123 Connecting member 124 Stopper 124a Lower stopper 124b Upper stopper 13 U-bolt 14 Nut

Claims

1. A fall prevention facility that is temporarily installed on a boom or jib to prevent a worker from falling, comprising a main rope connected to the worker via a safety belt and a support column for stretching the main rope, when tension is applied to the main rope, at least a part of the support column elastically deforms, The fall prevention facility, wherein the support column has a stopper for regulating the amount of elastic deformation.

2. The support column is a lower member erected on the boom or jib, an upper member disposed above the lower member and supporting the main rope, and an elastically deformable connecting member connecting the lower member and the upper member The fall prevention facility according to claim 1, having the above.

3. a lower stopper having a lower protruding portion protruding above the lower member, an upper stopper having an upper protruding portion protruding below the upper member and facing the lower protruding portion including in the non-elastically deformed state of the connecting member, the lower protruding portion and the upper protruding portion are separated, The fall prevention facility according to claim 2, wherein in the elastically deformed state of the connecting member, the lower protruding portion and the upper protruding portion come into contact with each other to regulate the amount of elastic deformation of the support column.

4. A support column for a fall prevention facility that stretches a main rope connected to a worker via a safety belt to prevent the worker from falling, when tension is applied to the main rope, at least a part of it elastically deforms, The support column having a stopper for regulating the amount of elastic deformation.

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