JP7782255B2 - Under-slab work aid device - Google Patents

Description

The present invention relates to an under-deck work support device used when working below a bridge deck.

It is desirable to replace existing aging bridges. However, in cases where land for replacement cannot be secured, reinforcement and repair measures are taken to extend the bridge's lifespan. For example, Patent Document 1 discloses a technique for reinforcing a bridge using a reinforcing structure that connects a pair of main girders extending in the direction of the bridge's length. When carrying out reinforcement measures or repairs using such reinforcing structures, hanging scaffolding is often installed on the bridge to enable work below the bridge deck. Hanging scaffolding is used not only to provide a foothold for workers, but also to transport equipment and materials using carts and to install lifting equipment for lifting equipment and materials.

Japanese Patent Application Publication No. 10-131119

However, construction using suspended scaffolding requires frequent transport of materials and equipment and the need to change the lifting equipment used to lift the materials, due to the scaffolding's load-bearing capacity, which requires a great deal of effort and time. These problems are not limited to bridge reinforcement, but are also common when work is carried out under a bridge deck, such as in bridge repairs.

The under-deck work assistance device that solves the above problem includes rails supported on the main girders of the bridge and extending in the direction of the bridge's extension, and a work vehicle supported on the rails and movable along the rails. The work vehicle has a work platform supported on the rails via a movement mechanism for moving the work vehicle and capable of carrying at least a load of equipment and materials, a support member erected on the work platform, and one or more lifting devices supported on the support member for lifting the load and transporting it to a predetermined location. The above "equipment and materials" means "materials and equipment" or "materials or equipment." Furthermore, "equipment" includes "tools."

This invention reduces the burden on workers working under bridge decks. It also improves the efficiency of work under bridge decks.

1 is a front view showing a schematic configuration of an embodiment of an under-slab work assist device. FIG. 1 is a top view showing a schematic configuration of one embodiment of an under-slab work assist device. FIG. FIG. 2 is a front view showing the schematic configuration of the lower end portion of the under-slab work auxiliary device. FIG. 3 is a side view showing the schematic configuration of the lower end portion of the under-slab work auxiliary device. FIG. 2 is a side view showing a schematic configuration of a support column and a swing arm. FIG. 10 is a top view schematically showing the rotation range of the second swing mechanism relative to the first swing mechanism. FIG. 10 is a top view schematically showing the rotation range of the arm body relative to the second swing mechanism. (a) A top view schematically showing an example of the rotation range of the arm body relative to the workbench, (b) a top view schematically showing another example of the rotation range of the arm body relative to the workbench, (c) a top view schematically showing another example of the rotation range of the arm body relative to the workbench. FIG. 2 is a top view schematically showing the general configuration of the reinforcing structure; FIG. 2 is a front view schematically showing the general configuration of the reinforcement unit. (a) A diagram showing a schematic diagram of how a base plate, etc. is connected to the main girder on the left side, (b) A diagram showing a schematic diagram of how a base plate, etc. is connected to the main girder on the right side, (c) A diagram showing a schematic diagram of how the upper chord, etc. is connected. (a) A diagram showing a schematic diagram of a work vehicle moving, (b) A diagram showing a schematic diagram of a state in which the remaining reinforcement materials are connected, and (c) A diagram showing a schematic diagram of a state in which the central metal fittings of adjacent reinforcement units are connected. (a) A diagram showing a schematic diagram of how the vertical beams are arranged, and (b) A diagram showing a schematic diagram of how the remaining reinforcing materials for adjacent reinforcing units are connected.

An embodiment of the under-slab work assist device will be described with reference to FIGS. 1 to 13. FIG.
As shown in Figure 1, the under-deck work support device 20 is used when various work is carried out under the deck of a bridge 10, such as reinforcement work for the bridge 10. Note that "under the deck of the bridge" means "below the deck of the bridge" and does not necessarily mean just below the deck. Furthermore, "under the deck of the bridge" also means "below the bridge girders."

The bridge 10 comprises multiple main girders 11 and a deck slab 12. The multiple main girders 11 extend in the extension direction of the bridge 10 and are arranged side by side in the width direction of the bridge 10. The main girder 11 has an upper flange 11a, a lower flange 11b, and a web 11c. The upper flange 11a is fixed to the deck slab 12. The web 11c connects the upper flange 11a and the lower flange 11b.

In the following, the direction of extension of the bridge 10, the direction toward the front of the paper, will be referred to as the forward direction, and the direction toward the back of the paper, will be referred to as the rear direction. Also, in the width direction of the bridge 10, the left side (right side in Figure 1) based on the forward direction will be referred to as the left direction, and the right side (left side in Figure 1) based on the forward direction will be referred to as the right direction.

As shown in FIGS. 1 and 2 , the under-deck work assisting device 20 includes a plurality of rail brackets 21 , a pair of rails 22 , and a work vehicle (work carriage) 30 .
The rail brackets 21 are connected to the lower flanges 11b of each of the pair of main girders 11. The rail brackets 21 connected to each main girder 11 extend in the left-right direction toward the other main girder 11 and are arranged side by side at a predetermined interval in the front-to-rear direction. The rail brackets 21 are, for example, made of T-shaped steel having a flange and a web. In this case, the rail brackets 21 are connected to the main girders 11 by clamping the flanges of the T-shaped steel against the lower flanges 11b of the main girders 11 with a clamp or the like. Note that the configuration of the rail brackets 21 does not need to be particularly limited as long as they are connected (fixed) to the main girders 11 and can support the rails 22. For example, steel plates or the like may be used. Furthermore, the means for connecting the rail brackets 21 to the main girders 11 does not need to be limited.

The rails 22 are supported by each of the pair of main girders 11 via rail brackets 21. In this embodiment, each rail 22 extends from one end of the main girder 11 to the other end in the fore-and-aft direction. The pair of rails 22 are arranged parallel to each other when viewed from above. Each rail 22 is constructed using, for example, an H-shaped steel (I-shaped steel) or the like.

(Overview of work vehicles)
As shown in FIGS. 1 and 2 , the work vehicle 30 is configured to be able to travel on a pair of rails 22 between a pair of main girders 11 .

The work vehicle 30 includes a moving mechanism 31, a work platform 32, a support column (support member) 33, and a swing arm 34. The work vehicle 30 is mainly made of steel.
The movement mechanism 31 is configured to allow the work vehicle 30 to travel along the pair of rails 22 and to stop the work vehicle 30 at any position on the pair of rails 22.

The work platform 32 is supported by a pair of rails 22 via a movement mechanism 31. The work platform 32 is configured to allow workers to board and to allow materials and equipment (such as cargo) to be placed on it. Examples of materials and equipment include various tools, various devices, and materials used for reinforcement and repair measures (reinforcement materials, repair materials). The work platform 32 is formed in a roughly rectangular shape when viewed from above the work vehicle 30.

In this embodiment, the support columns 33 are arranged on each corner side of the work platform 32 when viewed from above the work vehicle 30 , and extend upward to stand on the work platform 32 .
A swing arm 34 is provided on each support column 33. The swing arm 34 is configured to be rotatable relative to the support column 33 when viewed from above the work vehicle 30. The swing arm 34 is configured to be able to lift materials and equipment loaded on the work platform 32. A worker on board the work vehicle 30 lifts a reinforcing material with the swing arm 34, and then operates the swing arm 34 as appropriate to transport the reinforcing material to the desired position.

(Moving mechanism)
As shown in FIGS. 3 and 4, the movement mechanism 31 includes a slider 41, a stopper 42, and a regulating member 43.

The sliders 41 are disposed between each rail 22 and the work platform 32 at both ends of the work vehicle 30 in a side view. The sliders 41 are made of, for example, Tiltank (registered trademark). There are no particular restrictions on the configuration, number, or installation location of the sliders 41.

The stopping devices 42 are configured to be operated by an operator to hold the work vehicle 30 in a stopped state at a desired position on the pair of rails 22. The stopping devices 42 are connected to the lower end of the work platform 32 at each corner end of the work platform 32 when viewed from above the work vehicle 30. For example, the stopping devices 42 are pressed against the rails 22 by the operator's rotation operation, thereby holding the work vehicle 30 in a stopped state. There are no particular restrictions on the configuration, number, or installation location of the stopping devices 42.

The restricting member 43 is a member that restricts the work vehicle 30 from lifting up from the rail 22. The restricting member 43 is provided between the slider 41 and the stopper 42 when viewed from the side of the work vehicle 30. For example, when viewed from the front of the work vehicle 30, the restricting member 43 is formed in a clamp shape that engages with the rail 22 from the outside when the work vehicle 30 lifts up. There are no particular restrictions on the configuration, number, or installation position of the restricting member 43.

(Workbench)
As shown in FIGS. 3 and 4 , the workbench 32 has a pair of side frames 46 , a connecting frame 47 , and a workbench main body 48 .

Each of the pair of side frames 46 is disposed above the rail 22 so as to run along the rail 22. Each side frame 46 is made of, for example, an H-shaped steel beam. In this embodiment, the slider 41, stopper 42, and restricting member 43 described above are connected to each side frame 46.

The connecting frames 47 extend in the left-right direction and connect a pair of side frames 46. The connecting frames 47 are arranged side by side in the front-to-rear direction. The connecting frames 47 are made of, for example, channel steel or H-shaped steel. Support columns 33 are connected to some of the connecting frames 47.

The work platform main body 48 is disposed inside the pair of side frames 46 when viewed from above the work vehicle 30. The work platform main body 48 has a conveyor section 49 and a tread section 50.
The conveyor unit 49 is a device for assisting the movement of materials and equipment, such as reinforcement materials, on the work platform 32. The tread unit 50 is a portion of the work platform 32 that serves as a foothold for, for example, a worker to move around or work on. The conveyor units 49 are arranged side by side on either side of the tread unit 50 in the left-right direction. The conveyor unit 49 of this embodiment has a plurality of rollers 51 arranged side by side in the front-rear direction. Each roller 51 is configured to be rotatable around a rotation axis extending in the left-right direction. The conveyor unit 49 of this embodiment places materials and equipment on the plurality of rollers 51, and can easily transport the materials and equipment by the rotation of the rollers 51. Note that the conveyor unit 49 does not necessarily have to be configured with rollers 51 as long as it can easily transport the materials and equipment.

(Support: Supporting member)
As shown in FIG. 5 , the support column 33 is connected to, for example, the left-right ends of some of the connecting frames 47. The support column 33 is configured to be extendable and retractable in the vertical direction by a lower support column 55 and an upper support column 56 that form a double-tube structure. A height adjustment hole 57 is formed through the upper support column 56. A retaining member 58 (see FIG. 1 ) is disposed in the height adjustment hole 57 and engages with the upper end of the lower support column 55 to maintain the height of the support column 33. The retaining member 58 is configured, for example, by a fastening member having a shaft that is inserted into the height adjustment hole 57. The upper support column 56 may be formed with one height adjustment hole 57 or multiple height adjustment holes 57. The support column 33 of this embodiment is provided with one height adjustment hole 57 and is configured to be able to adjust its height in two stages: a retracted state and an extended state.

The extendable configuration of the support pillars (support members) 33 does not need to be limited to that of this embodiment, and they may be configured so that their height (length, amount of extension) can be freely adjusted by appropriate means. Also, while this embodiment uses support pillars 33 as the support members, there is no need to limit their configuration as long as they are capable of supporting the lifting device 78.

(Swing arm)
As shown in FIGS. 5 to 8, the swing arm 34 has a first swing mechanism 61, a second swing mechanism 62, and an arm body 63.

As shown in FIG. 6, the first swing mechanism 61 is a mechanism that rotatably supports the second swing mechanism 62 about a first rotation axis C1 so that the second swing mechanism 62 is positioned on the inside or outside of the pair of rails 22 when viewed from above. As shown in FIG. 7, the second swing mechanism 62 is a mechanism that rotatably supports the arm main body 63 about a second rotation axis C2.

As shown in FIG. 5 , the first swing mechanism 61 includes an upper bracket 66 , a lower bracket 67 , a first rotating shaft member 68 , and a rotating tool 69 .
The upper bracket 66 is connected to the upper end of the upper support column 56. The lower bracket 67 is connected to the center of the upper support column 56 (lower than the upper bracket 66). The upper bracket 66 and the lower bracket 67 are provided so as to protrude forward from the upper support column 56, for example.

The first rotating shaft member 68 is connected to the upper bracket 66 and the lower bracket 67. The first rotating shaft member 68 is disposed between the upper bracket 66 and the lower bracket 67 so as to extend in the vertical direction. The central axis of the first rotating shaft member 68 is the first rotation axis C1.

The rotating device 69 has its base end connected to the first rotating shaft member 68 so as to be rotatable around the first rotation axis C1. The rotating devices 69 are provided at a position near the upper end of the first rotating shaft member 68 and a position near the lower end of the first rotating shaft member 68. In this embodiment, two rotating devices 69 are connected to a position near the upper end of the first rotating shaft member 68. A second swing mechanism 62 is connected to the tip of each rotating device 69.

The second swing mechanism 62 has a connecting member 71 , a pair of upper and lower support-side brackets 72 , an arm-side bracket 73 , and a second rotating shaft member 74 .
The connecting member 71 extends in the vertical direction and connects the tip ends of the rotating tools 69. A pair of upper and lower support-side brackets 72 protrude from the connecting member 71 on the side opposite the first rotating shaft member 68. The pair of upper and lower support-side brackets 72 are provided on the upper end of the connecting member 71 and on a portion of the connecting member 71 near its lower end.

The arm-side bracket 73 is a member connected to the base end of the arm body 63. The arm-side bracket 73 is disposed between a pair of upper and lower support-side brackets 72.
The second rotation shaft member 74 is a member that rotatably connects the arm-side bracket 73 to the pair of upper and lower support-side brackets 72. The center axis of the second rotation shaft member 74 is the second rotation axis C2.

The arm body 63 has a base end member 76 , an arm member 77 , and a lifting device 78 .
The base end member 76 is a member that forms the base end of the arm main body 63, and is a member to which the arm side bracket 73 described above is connected.

The arm member 77 is connected to the base member 76. The arm member 77 extends in one direction from the base member 76. The arm member 77 supports a lifting device 78 that is movable along the extension direction of the arm member 77.

The lifting device 78 has a ring-shaped hook 79 located below the arm member 77. A chain block (not shown) is attached to the ring-shaped hook 79 and is used by workers to move the reinforcement material. Note that the configuration of the lifting device 78 does not need to be limited as long as it is capable of lifting loads such as equipment and materials and transporting them to the desired location. Furthermore, multiple lifting devices 78 may be supported on the support member (pillar 33).

As shown in Figure 8(a), when the second swing mechanism 62 is positioned directly above the side frame 46, the swing arm 34 is configured so that the arm body 63 can rotate around the second rotation axis C2 so as to straddle the inside and outside of the side frame 46.

Furthermore, as shown in FIG. 8(b), when the second swing mechanism 62 is rotated to the maximum extent toward the inside of the pair of side frames 46 around the first rotation axis C1, the swing arm 34 is configured so that the arm body 63 can rotate inside the pair of side frames 46 around the second rotation axis C2.

Furthermore, as shown in FIG. 8(c), when the second swing mechanism 62 is rotated to the maximum extent around the first rotation axis C1 toward the outside of the pair of side frames 46, the swing arm 34 is configured so that the arm body 63 can rotate around the second rotation axis C2 toward the outside of the pair of side frames 46.

(An example of a bridge reinforcement structure)
9 and 10 , an example of a reinforcement structure formed by reinforcement work using the above-mentioned under-slab work auxiliary device 20 will be described. The reinforcement structure is formed by connecting various steel materials to connection targets using fastening members or the like.

As shown in Figure 9, the reinforcement structure has a reinforcement unit 80 and a vertical beam 90. The reinforcement unit 80 connects a pair of main beams 11 in a direction intersecting the left-right direction. The reinforcement units 80 are arranged side by side in the front-to-rear direction. The vertical beam 90 connects adjacent reinforcement units 80 in the front-to-rear direction. As shown in Figure 10, the reinforcement unit 80 is formed to connect a pair of main beams 11. The reinforcement units 80 are arranged side by side in the front-to-rear direction.

The reinforcement unit 80 includes a base plate 81, an upper gusset plate 82, a lower gusset plate 83, an upper chord member 84, an upper central gusset plate 85, a central bracket 86, a lower central gusset plate 87, a lower chord member 88, and a diagonal member 89.

The base plate 81 is a component that is connected to the web 11c of the main girder 11 and is arranged along the web 11c. The upper gusset plate 82 is a component that is connected to the upper end of each base plate 81. The lower gusset plate 83 is a component that is connected to the portion of each base plate 81 near the lower end.

The upper chord member 84 is a member that is installed on the upper gusset plate 82. The upper central gusset plate 85 is a member that is connected to the center portion of the upper chord member 84. The central fitting 86 is a member that extends downward from the upper central gusset plate 85 and connects the upper central gusset plate 85 to the lower central gusset plate 87. The central fitting 86 is also a member to which the above-mentioned longitudinal beam 90 is connected. The lower central gusset plate 87 is a member that is connected to the lower end of the central fitting 86.

The lower chord 88 is a member that is installed on the lower gusset plate 83, and the lower central gusset plate 87 is connected to its center. The diagonal member 89 is a member that connects the upper gusset plate 82 and the lower central gusset plate 87, or the lower gusset plate 83 and the upper central gusset plate 85.

(Example of a method for constructing a reinforced structure)
11 to 13, an example of a method for constructing a reinforcement structure using the under-slab work auxiliary device 20 will be described. In the construction method of this embodiment, the reinforcement units 80 are constructed in order, starting with the reinforcement unit 80 located at the rearmost position. Furthermore, the vertical beam 90 is disposed during the construction of the reinforcement unit 80 located in front of the reinforcement unit 80 after construction.

In the following, it is assumed that all work performed by workers, other than moving the work vehicle 30, is performed with the work vehicle 30 stopped by the stopper 42. Furthermore, it is assumed that each support pillar 33 is basically in an extended state.

As shown in Figure 11(a), a worker, while riding on a work platform 32 loaded with various reinforcing materials, moves the work vehicle 30 to the construction position of the rearmost reinforcement unit 80. Specifically, the worker moves the work vehicle 30 to the front side of the connection position of the base plate 81 to the web 11c of the left main girder 11.

Next, the worker operates the left rear swing arm 34 as needed to transport the base plate 81 to the vicinity of the web 11c of the left main girder 11. The worker then connects the base plate 81 to the web 11c.

Next, the worker operates the swing arm 34 located at the rear left side to transport the upper gusset plate 82 and the lower gusset plate 83 to the vicinity of the base plate 81. The worker then connects the upper gusset plate 82 and the lower gusset plate 83 to the base plate 81.

Next, as shown in Figure 11(b), the worker moves the work vehicle 30 slightly forward. More specifically, the worker moves the work vehicle 30 to the front side of the connection position of the base plate 81 to the web 11c of the right main girder 11.

Then, the worker operates the right rear swing arm 34 as appropriate to connect the base plate 81 to the web 11c of the right main girder 11 and to connect the upper gusset plate 82 and lower gusset plate 83 to the base plate 81.

Next, as shown in Figure 11(c), the worker moves the work vehicle 30 rearward to a position where the upper chord member 84 is positioned between the pair of rear supports 33 when viewed from above. Then, the worker appropriately operates the pair of swing arms 34 located on the rear side to connect the upper chord member 84 to the upper gusset plate 82, and then connects the upper center gusset plate 85 to the upper chord member 84.

Next, as shown in Figure 12(a), the worker moves the work vehicle 30 to the front side of the upper chord member 84 when viewed from above. At this time, if the extended support column 33 interferes with the upper chord member 84, the worker temporarily retracts the support column 33 before moving the work vehicle 30.

Next, as shown in Figure 12(b), the worker connects the central bracket 86, lower central gusset plate 87, lower chord member 88, and each diagonal member 89 while appropriately operating the pair of swing arms 34 located at the rear. This completes the rearmost reinforcement unit 80.

Next, the workers begin constructing the reinforcement unit 80 adjacent to the reinforcement unit 80 in the rearmost position.
12(c), a worker appropriately operates the pair of swing arms 34 located on the front side to connect the base plate 81, upper gusset plate 82, lower gusset plate 83, upper chord member 84, upper central gusset plate 85, and central bracket 86. The central bracket 86 connected at this time is a reinforcing member connected to the upper central gusset plate 85 from the rear side.

As shown in Figure 13(a), the worker connects the central metal fitting 86 of the reinforcement unit 80 with the vertical beam 90 while appropriately operating all of the swing arms 34. Once the vertical beam 90 is attached, the worker moves the work vehicle 30 to the front of the reinforcement unit 80 being constructed. At this time, if the strut 33 interferes with the upper chord member 84, the worker will retract the strut 33 before moving the work vehicle 30.

As shown in Figure 13(b), the worker connects the central bracket 86, lower central gusset plate 87, lower chord member 88, and diagonal member 89 while appropriately operating the pair of swing arms 34 located at the rear. The central bracket 86 connected at this time is a reinforcement member connected to the upper central gusset plate 85 from the front. This completes the adjacent reinforcement unit 80. Thereafter, the worker repeats the various tasks described using Figures 12(a) to 13(b) to form the reinforcement structure.

The effects of this embodiment will be described.
(1) The under-deck work support device 20 is supported by the main girders 11 of the bridge 10 and includes rails 22 extending in the extension direction of the bridge 10, and a work vehicle 30 supported by the rails 22 and movable along the rails 22. The work vehicle 30 includes a work platform 32 that is supported by the rails 22 via a movement mechanism 31 for moving the work vehicle 30 and is capable of carrying at least a load of materials and equipment, a support member (such as a support column 33) erected on the work platform 32, and one or more lifting devices 78 that are supported by the support member and that lift the load and transport it to a predetermined position.

This under-deck work auxiliary device 20 allows the work vehicle 30 to move under the deck and transport loads such as materials and equipment (and workers) to the desired location. Using one or more lifting devices 78 supported by support members erected on the work platform 32, loads such as materials and equipment can be easily transported to a location suitable for under-deck work.

The under-slab work auxiliary device 20 can also be used to place the transported load in a predetermined position.
Furthermore, since a reaction force against the load on the rail 22 is obtained from the main girder 11, it is possible to increase the load-bearing capacity of the rail 22. This allows the work vehicle 30 to carry more loads such as equipment and materials.

In other words, the under-deck work support device 20 allows for more equipment and materials to be loaded, and since the equipment, workers, and lifting equipment can all be transported to the work site together, it is possible to improve the efficiency and labor-saving of under-deck work and reduce the burden on workers.

(2) The work vehicle 30 has a swing arm 34 that includes an arm body 63 rotatably supported on a support member (such as a support column 33) when viewed from above, and a lifting device 78 supported on the arm body 63.

In this way, the work vehicle 30 is provided with a swing arm 34 that moves together with the work platform 32. Therefore, by rotating the swing arm 34 while a load such as equipment or materials is lifted by the lifting device 78, the load can be easily moved (or placed) on the work vehicle 30. This makes it possible to further improve the efficiency and reduce the labor required for work under the deck, and further reduce the burden on workers.

(3) The work platform 32 has a conveyor section 49 that assists workers in moving materials and equipment on the work platform 32 and a step section 50 that serves as a foothold for the workers.
The work platform 32 has a conveyor section 49, which allows workers to easily move loads such as materials and equipment on the work platform 32. In addition, the work platform 32 has a tread section 50, which ensures a foothold for workers performing various tasks.

(4) The rail 22 is supported on the main girder 11 via a rail bracket 21 connected to the main girder 11.
This allows for greater freedom in the arrangement of the rails 22 relative to the main girders 11. For example, the rails 22, and therefore the work vehicle 30, can be arranged so as to pass through an area that is easy to perform various tasks and highly safe. Furthermore, even in cases where a pair of adjacent main girders 11 for supporting the pair of rails 22 are not arranged parallel to one another (such as when the spacing between the pair of main girders 11 varies depending on the location in the extension direction), the pair of rails 22 can be arranged parallel by supporting the rails 22 on the main girders 11 via the rail brackets 21, allowing the rails 22, and therefore the work vehicle 30, to be arranged easily and suitably.

(5) The support members (such as the support posts 33) are configured to be extendable and contractible in the vertical direction.
This allows the height (length) of the support members (and the lifting device 78) to be freely adjusted depending on the situation at hand, such as the work situation and the shape of the bridge to which it is applied, etc. As a result, the applicability and versatility of the under-deck work auxiliary device 20 can be greatly improved.

(6) The swing arm 34 has a first swing mechanism 61 connected to a support member (such as the support column 33) and a second swing mechanism 62 connected to the support member via the first swing mechanism 61. The first swing mechanism 61 is configured to rotate the second swing mechanism 62 around the first rotation axis C1. The second swing mechanism 62 is configured to rotate the arm main body 63 around the second rotation axis C2.

In other words, the swing arm 34 is configured so that the second rotation axis C2, which is the center of rotation of the arm main body 63, can move around the support member (such as the support column 33). This allows for greater flexibility in the position of the arm main body 63, and ultimately in the transport position of materials and other loads using the lifting device 78.

(7) The support members (such as the support columns 33) are provided at each corner of the rectangular work table 32 when viewed from above. The swing arm 34 is supported by each support member.
This allows the area above the work platform 32 to be covered by the short arm body 63, thereby reducing the mechanical load acting on the support member when lifting loads such as materials and equipment onto the arm body 63. In addition, the support member according to the work, the lifting device 78 supported by the swing arm 34 can be selected and used as needed, making it possible to improve work efficiency.

The above describes one embodiment of the under-slab work assist device, but the present invention is not limited to the above embodiment and can be modified as appropriate without departing from the spirit of the invention. For example, this embodiment can be implemented with the following modifications. This embodiment and the following modifications can be implemented in combination with each other as long as they are not technically inconsistent.

- The shape of the work platform 32, the arrangement of the support members (pillars 33, etc.), and the length of the arm body 63 may be changed as appropriate depending on the content of the work under the deck, including the shape of the reinforcement structure or bridge to be constructed.

- The swing arm 34 may be configured to include an arm main body 63 that is rotatably supported on a support member (such as a support column 33) when viewed from above. Therefore, the swing arm 34 is not limited to a configuration including a first swing mechanism 61 and a second swing mechanism 62, and may be configured, for example, such that the arm main body 63 is supported on the support column 33 via the first swing mechanism 61.

- In addition, in this embodiment, the under-slab work auxiliary device 20 has been described as being able to easily transport loads such as equipment and materials, but the under-slab work auxiliary device 20 can also be used to set transported loads such as reinforcement materials in a predetermined position.

The support member (the support column 33, etc.) may have a fixed height.
- The support member (pillar 33, etc.) may be configured to be freely raised and lowered, so that when it is raised, work can be performed as described in this embodiment, and when it is lowered, the under-deck work auxiliary device 20 can be stored compactly.

- The support members (pillars 33, etc.) may be detachably attached to the work platform 32. In this case, too, work can be performed as described in this embodiment when the support members are attached to the work platform 32 and installed upright, and when removed, the under-slab work auxiliary device 20 can be stored compactly.

The rail 22 is not limited to being supported on the main girder 11 via the rail bracket 21, but may be supported directly on, for example, the lower flange 11b of the main girder 11.
The configuration of the work platform 32 does not have to be limited to that of the present embodiment as long as it is capable of carrying loads such as materials and equipment. It is desirable that the configuration ensures a foothold for workers when the loads such as materials and equipment are placed on it. The work platform 32 may not have a conveyor unit 49, and loads may be placed on the tread unit 50, or workers may stand on it.

In this embodiment, the main girder 11 is described as a steel girder, but it may of course be a concrete girder.
In the present embodiment, the description has been given assuming that the under-deck work auxiliary device 20 is movably supported by the rails 22, and that the work platform 32 and support members (such as the support columns 33) are disposed between adjacent main girders 11. However, the under-deck work auxiliary device 20 may be configured so that the work platform 32 and at least a portion of the support members are disposed below the lower flange 11b of the main girder 11, and that the work platform 32 is movably supported by the rails 22 supported by the main girders 11. In this case, a portion of the work platform 32 may be formed to extend outward in the width direction of the main girders 11 that support the rails 22, thereby ensuring a large range for the work platform 32 (a foothold range for workers) and enabling efficient work.

C1...first rotating shaft, C2...second rotating shaft, 10...bridge, 11...main girder, 11a...upper flange, 11b...lower flange, 11c...web, 12...deck slab, 20...under-deck work auxiliary device, 21...rail bracket, 22...rail, 30...work vehicle, 31...moving mechanism, 32...work platform, 33...support (support member), 34...swing arm, 41...slider, 42...stopper, 43...regulating member, 46...side frame, 47...connecting frame, 48...work platform main body, 49...conveyor section, 50...tread section, 51...roller, 55...lower support, 56...upper support, 57...height adjustment hole, 58...retaining material, 61...first swing swing mechanism, 62...second swing mechanism, 63...arm body, 66...upper bracket, 67...lower bracket, 68...first rotating shaft member, 69...rotating tool, 71...connecting member, 72...pillar side bracket, 73...arm side bracket, 74...second rotating shaft member, 76...base end member, 77...arm member, 78...lifting device, 79...annular hook, 80...reinforcement unit, 81...base plate, 82...upper gusset plate, 83...lower gusset plate, 84...upper chord member, 85...upper central gusset plate, 86...central fitting, 87...lower central gusset plate, 88...lower chord member, 89...diagonal member, 90...stringer.

Claims (7)

a rail supported by the main girder of the bridge and extending under the deck of the bridge in the extension direction of the bridge;
a work vehicle supported by the rails and movable along the rails under the deck of the bridge ,
The work vehicle is
a work platform that is supported on the rails via a movement mechanism for moving the work vehicle and that is capable of loading at least equipment and materials;
a support member erected on the workbench;
one or more lifting devices supported by the support member for lifting the load and transporting it to a predetermined position ;
The work platform has a conveyor section that assists a worker in moving the load on the work platform and a step section that serves as a foothold for the worker,
The conveyor sections are arranged side by side in the width direction of the bridge so as to sandwich the tread section.
Auxiliary device for working under the floor slab. The under-deck work assisting device according to claim 1 , wherein the rail is supported by the main girder via a rail bracket connected to the main girder. a rail supported by the main girder of the bridge and extending under the deck of the bridge in the extension direction of the bridge;
a work vehicle supported by the rails and movable along the rails under the deck of the bridge ,
The work vehicle is
a work platform that is supported on the rails via a movement mechanism for moving the work vehicle and that is capable of loading at least equipment and materials;
a support member erected on the workbench;
one or more lifting devices supported by the support member for lifting the load and transporting it to a predetermined position ;
The rail is supported on the main girder via a rail bracket connected to the main girder,
The rail brackets are made of T-shaped steel beams that have flanges and webs and extend from the main girder in the width direction of the bridge, and are arranged side by side at predetermined intervals in the extension direction of the bridge. The flanges are connected to the main girder with the flanges abutting against the lower flanges of the main girder.
Auxiliary device for working under the floor slab. The under-slab work auxiliary device according to any one of claims 1 to 3 , wherein the support member is configured to be extendable and contractible in the vertical direction. The work vehicle is
The under-deck work auxiliary device according to any one of claims 1 to 4, further comprising a swing arm comprising an arm body rotatably supported on the support member in a top view, and the lifting device supported on the arm body. The swing arm is
a first swing mechanism coupled to the support member;
a second swing mechanism connected to the support member via the first swing mechanism,
the first swing mechanism is configured to be able to rotate the second swing mechanism around a first rotation axis as a rotation center in a top view,
The under-slab work assist device according to claim 5 , wherein the second swing mechanism is configured to be able to rotate the arm body around a second rotation axis as a rotation center in a top view. The workbench has a rectangular shape when viewed from above,
The support members are provided at each corner of the work table,
The under-deck work auxiliary device according to claim 5 or 6 , wherein the swing arm is supported by each of the support members.