JP2753216B2 - Elevating safety fence device for manhole - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety fence device for a manhole provided for inspection and work of a sewer, an underground power cable, a communication cable, a gas pipe, and the like.

[0002]

2. Description of the Related Art Conventionally, when working inside a manhole, a manhole is removed and an operator enters the inside. For this reason, during the work, the opening of the manhole is open,
Even if a partition or the like is provided on the outer periphery, a person or the like may fall into the manhole.

In order to prevent this, it is known that a safety fence device is provided inside the manhole so as to be able to move up and down, and at the time of work, the safety fence of the safety fence device is raised to form a safety fence at the opening of the manhole. (Jun 60-1
No. 85761 (see Japanese Utility Model Application Laid-Open No. 62-94133).

[0004]

However, since the safety fence of the safety fence device does not have an upper cover, the manhole outer cover is removed, and before the safety fence of the safety fence device is lifted, The manhole opening is open. For this reason, the operator himself may fall down from the opening. Further, even when the safety fence is raised, there is a danger that a third party may fall from the entrance since the entrance to the fence is open.

Therefore, an object of the present invention is to prevent a worker or the like from falling into the manhole before the safety fence is lifted after the manhole outer cover is removed, and
The purpose is to prevent a third person from falling into the manhole from the doorway even after lifting.

[0006]

In order to solve the above-mentioned problems, according to the present invention, a ladder is attached to an inner peripheral wall of a manhole in a vertical direction, and movable columns are respectively provided on both columns of the ladder so as to be movable up and down. On one side of a surface connecting the two movable columns, arc-shaped horizontal bars are attached to the two movable columns at predetermined intervals in the vertical direction, and vertical bars are attached at predetermined intervals along the horizontal columns, A safety fence is formed by the movable strut, the horizontal bar and the vertical bar, a lid is provided at an upper end of the safety fence, and a wire hanging a counterweight at one end passes through a fulcrum provided on the ladder post. Thus, it was connected to the movable column.

[0007] Since the lid is provided at the upper end of the safety fence, even if the outer cover of the manhole is removed, the lid of the safety fence can prevent a worker or the like from falling into the manhole. Further, since the horizontal bar is provided below the safety fence lid, even if the safety fence is raised above the ground, the horizontal bar can prevent a third person or the like from falling into the manhole during work. Furthermore, since the safety fence device has a counterweight,
The safety fence can be easily raised and lowered.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

A safety fence device according to the present invention is shown in FIGS. Inner peripheral wall 2 of manhole provided inside ground 21
The ladder 6 in the up-down direction is attached to 6 via brackets 25, 25 'and support arms 24, 24' for supporting the ladder. Since the ladder 6 is used for removing the manhole cover 23 provided in the manhole opening 22 and allowing a worker to enter the inside of the manhole, the upper end of the ladder 6 is arranged near the lower surface of the manhole cover 23,
Its lower end reaches the bottom of the manhole.

A pulley mounting plate 17 is fixed to the ladder 6 near the upper ends of the columns 7 and the pulley mounting plate 17 is provided with a double row of pulleys 8. A movable column 5 is passed between the double-row pulleys, and the movable column 5 can be moved up and down with respect to both columns 7 of the ladder 6 by pulleys 8.

On one side of the surface connecting the two movable columns 5, on the opposite side to the side where the ladder 6 is located, arc-shaped horizontal bars 4 are attached to the two movable columns 5 at predetermined intervals in the vertical direction. The vertical bars 3 are attached along the horizontal bars 4 at predetermined intervals. The movable fence 5, the horizontal bar 4 and the vertical bar 3 form a safety fence 1. Further, a horizontal bar 12 is provided at the upper end between the two movable supports 5 so as to be freely opened and closed, and serves as a clue when raising the safety fence and as a gate of the safety fence entrance 20.

A lid 2 is provided at the upper end of the safety fence 1. The lid 2 can be opened and closed by a hinge 18. The hinge 18 is provided on the lid 2 on the side opposite to the side on which the movable column 5 is arranged.

Further, the safety fence 1 is provided on the support 7 of the ladder 6.
Fixed fence 1 consisting of horizontal and vertical arc-shaped crossbars to cover
3 are formed. The safety fence 1 and the fixed fence 13 are shown in FIG.
As shown in the figure, has an arc of similar curvature,
The safety fence 1 can move vertically inside the fixed fence 13.

Further, a wire 15 having a counterweight 11 suspended at one end is connected to a wire joint provided near a lower end of the movable support 5 via a fulcrum pulley 14 provided on the support 7 of the ladder 6. 19 is connected.
Arms 24, 24 'are fixed to the brackets 25, 25', and a vertical guide member 16 is attached to the arms 24, 24 '. The above counter weight 11
Moves up and down while being guided by the guide member 16. The fulcrum pulley 14 is provided at a position above the wire joint 19 even when the safety fence 1 is raised to the highest position. Therefore, the wire 15 does not come off from the fulcrum pulley 14. When the safety fence 1 is raised, the counterweight 11 is lowered according to the guide member 16, and when the safety fence 1 is lowered, the counterweight 11 is raised according to the guide member 16. Thereby, the safety fence 1 can be easily raised and lowered.

A stopper 9 is provided at the upper end of the support 7 of the ladder 6, and a stopper 9 'is provided on the movable support 5 at a position where the safety fence 1 is engaged with the stopper 9 when the safety fence 1 is raised to the highest position. ing.

When the safety fence 1 is raised, the safety fence 1 stops in a state of being balanced with the counterweight 11.
When a vertical force is applied to the arm, the arm is easily moved up and down, which is rather unstable. For this reason, both stoppers 9,
The safety fence 1 is fixed in a state where the safety fence 1 is pulled up to the maximum through the stopper pins 10.

Next, a method of using the safety fence device will be described.

In FIG. 2, since the movable column 5 is housed in the manhole, the wire joint 19 is at the lowest position, and therefore, the counterweight 11 is in the state of being pulled up to the highest position.

When a worker or the like enters the inside of the manhole,
First, the manhole outer cover 23 is removed. With the manhole outer cover 23 removed, the cover 2 provided at the upper end of the safety fence 1 prevents a worker or the like from falling into the manhole. Also, after opening the manhole cover 23,
When the worker raises the safety fence 1, the counterweight 1
The safety fence 1 can easily be moved as the
Can be raised.

FIG. 4 shows a state in which the safety fence 1 is raised. When the safety fence 1 is raised, the safety fence 1 appears on the ground. By passing the stopper pin 10 between the stoppers 9 and 9 'in the most raised state, the safety fence 1 is fixed in the most raised state.

The height of the safety fence 1 is set lower than the height of a person according to the Occupational Safety and Health Regulations and the Safety Standard for Fall Protection of the Temporary Industrial Association in order to prevent a third party from falling down. As it is, the worker does not enter the inside of the safety fence 1. However, since only the horizontal bar 12 is provided at the entrance 20 between the two movable columns 5 of the safety fence 1, the horizontal bar 12 is removed, and the lid 2 is opened upward.
The restriction above the entrance 20 is removed, and the worker
You can enter inside the safety fence 1 from 0. When the worker descends into the manhole, the horizontal bar 12 is restored,
By closing the lid 2, it is possible to prevent a third party or the like from falling into the manhole.

[0022]

According to the present invention, since the lid is provided at the upper end of the safety fence, even if the manhole outer cover is removed, the fall of the worker can be prevented by the cover of the safety fence into the manhole. . In addition, since the above-mentioned safety fence that can freely move up and down is provided, it is possible to prevent a third person or the like from falling into the manhole during the work by raising the safety fence above the ground. Furthermore, since the safety fence device has a counterweight,
The safety fence can be easily moved up and down.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a part of a safety fence device of the present invention.

FIG. 2 is a side view showing the safety fence device of the present invention.

FIG. 3 is a sectional view taken along line AA.

FIG. 4 is a side view showing a state in which the safety fence of FIG. 2 is raised.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Safety fence 2 Lid 3 Vertical bar 4 Horizontal bar 5 Movable support 6 Ladder 7 Support 8 Pulley 9 Stopper 10 Stopper pin 11 Counter weight 12 Horizontal bar 13 Fixed fence 14 Support point pulley 15 Wire 16 Guide member 17 Pulley mounting plate 18 Hinge 19 Wire Joint 20 Doorway 21 Ground 22 Manhole opening 23 Manhole outer cover 24, 24 'Support arm 25, 25' Bracket 26 Manhole inner peripheral wall

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tetsuya Matsumoto 3-3-22 Nakanoshima, Kita-ku, Osaka-shi Kansai Electric Power Co., Inc. (56) References JP-A 3-25636 (JP, U) JP-A 62 −94133 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) E02D 29/12

Claims (1)

(57) [Claims] A ladder is mounted on the inner peripheral wall of the manhole in the up-down direction, and movable columns are respectively provided on both columns of the ladder so as to be able to move up and down. Attached to the movable columns at predetermined intervals in the vertical direction, vertical bars are attached at predetermined intervals along the horizontal beams, and a safety fence is formed by the movable columns, horizontal beams, and vertical beams. An elevating and lowering type safety fence device for manholes, wherein a lid is provided at an upper end of the safety fence, and a wire hanging a counterweight at one end is connected to the movable support via a fulcrum provided on the support of the ladder.