JPH10159116A - Ladder and manhole with falling preventive tool for manhole - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manhole an opening part of which is safe especially at the time of going in and out of the manhole at the time of going up and down in a water reservoir tank, etc., and which prevents falling at the time of opening a cover of the manhole. SOLUTION: Two of upper and lower fixed shafts 5, 15 are separately provided in the neighbourhood of upper end parts of both leg parts 2 of a ladder main body 1 roughly vertically fixed on an inwall surface of a water reservoir tank, etc., or its manhole 18. Thereafter, falling preventive tools are respectively fixed free to revolve against both of the leg parts 2 and by a fixing means in vertical and horizontal states by respectively inserting the upper part fixed shaft 5 in a slot 12 formed on a connecting member 9 of the falling preventive tools 4 set on an opening part of the manhole and the lower part fixed shaft 15 in a slot 14 formed on the other end of a holder member 11 constituted with its one end axially installed on the connecting member 9 free to revolve.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ladder for manholes installed in a water storage tank, water and sewage system, a common ditch or a common ditch for electric wires, and more particularly to a fall for preventing a person from falling from an opening of the manhole. The present invention relates to a ladder provided with a protection device.

[0002]

2. Description of the Related Art Conventionally, when repairing or inspecting a water storage tank or the like, a lid installed at an opening of a manhole is removed, and a ladder is lowered from the opening to thereby descend into the water storage tank.
Alternatively, the person descended by steps installed on the wall in the manhole at appropriate intervals.

[0003]

However, when trying to descend into a water storage tank along a conventional ladder or step, when the lid is opened, there is a case where the water tank accidentally falls into the water storage tank. A person who tries to check the repair and inspection status of the water tank etc. may fall accidentally.

[0004] In particular, when the rising height from the ground surface of the manhole to the upper end of the opening is low, the above-mentioned risk is further increased. While bending, first put one foot into the manhole from the opening, put one foot on the ladder or step and put the other foot down, but at this time, the upper end of the opening of the manhole where you will grab by hand is in a lower position Because of this, it is unstable to support the body, and there is a problem in terms of safety.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and it is intended to prevent a fall when a manhole cover is opened, and to provide a water tank or the like. When going up and down inside, especially when entering and exiting the manhole, it is intended to provide a safe and easy operation in and out of the opening, the gist of which is a water tank or the like The upper and lower fixed shafts are installed near the upper ends of both legs of the ladder main body, which is fixed substantially vertically to the inner wall surface of the manhole, and the upper fixed shaft is installed in the opening of the manhole. The lower fixed shaft is inserted into the elongated hole formed in the connecting member of the fall prevention device, and the lower fixed shaft is inserted in the elongated hole formed in the other end of the holder member rotatably mounted on the connecting member at one end, respectively. The fall prevention device can be freely rotated with respect to the both legs. And in a manhole with a ladder and 該梯Ko with manhole for fall prevention device, characterized in that a configuration in which each fixed in the vertical and horizontal position by the fixing means.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to an embodiment shown in FIGS. 1 to 7. In the drawings, A is a ladder with a fall prevention device for a manhole according to the present invention, and a ladder main body 1 is provided. And a fall prevention device 4. The ladder main body 1 includes a pair of left and right vertical legs 2, 2 disposed in parallel, and a horizontal rail 3, horizontally mounted between the two legs 2, 2.
In the vicinity of the upper end of the ladder body 1, a fall prevention tool 4 having fixing means capable of being fixed at horizontal and vertical positions, respectively, will be described later. Upper ends 2A, 2A of parts 2, 2
It is mounted so as to be rotatable by a fixed shaft 5 on the upper side, which is suspended horizontally.

2 and 3, an outer frame member 6 having an arc portion 6A at the right end and having a substantially dome shape in a plan view, and mounted in the outer frame member 6 in a grid pattern. A fall prevention device main body 8 including a lattice component 7, a pair of left and right connection members 9, 9 protruding in parallel and separated from both sides of a left end portion of the fall prevention device main body 8, and a base of the connection member 9. It is mainly composed of a holder member 11 in which one end 11A is rotatably mounted on the inside so as to be rotatable about the shaft 10.
Here, the ladder main body 1 and the fall prevention device 4 are preferably made of rust-resistant stainless steel, for example, or made of various metals such as iron and aluminum, and coated with a rust-preventive paint.

[0008] Although not shown, if a pull-up member is attached to an appropriate location of the fall prevention device main body 8, the fall prevention device 4 can be easily caused. Further, the inside of the outer frame member 6 of the fall prevention device 4 is not limited to a lattice-like structure as shown, but may be a grating-like or mesh-like structure. Further, the outer frame member 6 has a shape having an arc portion 6A in a part thereof according to the shape of the opening of the manhole. However, when the shape of the opening of the manhole is rectangular, it may be rectangular. However, it is needless to say that the size of the fall prevention device main body 8 needs to be slightly smaller than the area of the opening of the manhole.

Reference numeral 12 denotes an elongated hole formed substantially at the center of the connecting member 9 of the fall prevention tool 4. The elongated hole 12 extends in the longitudinal direction of the connecting member 9, and is inserted into the elongated hole 12. Due to the upper fixed shaft 5, the fall prevention device 4 is attached to the ladder main body 1.
Are mounted so as to be rotatable and movable along the elongated holes 12 inside the upper end portions 2A of the two leg portions 2 and a lower end, which will be described later, A concave groove 13 that engages with the fixed shaft 15 is formed.

Reference numeral 14 denotes an elongated hole formed in the straight other end portion 11B of the holder member 11. The elongated hole 14 is formed in the other end portion 11B.
The lower fixed shaft 15 which is located below the upper fixed shaft 5 attached to the two leg portions 2 and has one end fixed to the leg portion 2 is inserted into the elongated hole 14. doing. Therefore, the other end portion 11B of the holder member 11 is configured to be rotatable with respect to the two leg portions 2 of the ladder main body 1 and to be movable along the elongated hole 14. The diameter of the lower fixed shaft 15 is set to be large enough to engage with the concave groove 13 formed on the distal end surface of the connecting member 9.

Here, the connecting member 9 of the fall prevention device 4 is used.
The upper end 2A of the leg 2 is attached to the inside thereof near the upper end 2A by an upper fixed shaft 5, and the one end 11A of the holder member 11 is mounted inside the base of the connecting member 9 by a lower fixed shaft 15. As shown in FIGS. 5 and 7, the gap between the other end portion 11 </ b> B of the holder member 11 and the leg portion 2 is equal to or greater than the thickness of the connecting member 9 of the fall prevention device 4. H is formed, and the lower fixed shaft 15 is exposed between the gaps H.

Next, a method of using the ladder A according to the present invention will be described. As shown in FIG. 1, a water storage tank, a water and sewage system, a common groove, a wire common groove, etc. (Hereinafter referred to as a water storage tank or the like). In this case, as shown by the solid line in FIGS. 1 and 2, when the fall prevention device 4 is rotated 90 ° with respect to the leg 2 of the ladder main body 1 installed in a vertical state and held in a horizontal state, The ladder main body 1 is fixed by adjusting the ladder main body 1 up and down so that the upper surface thereof is installed at a position slightly lower than the lower surface of the lid 19 installed at the opening of the manhole 18.

Here, the fall prevention tool 4 rotates the fixed shaft 5 by fitting an elongated hole 12 formed in the connecting member 9 with the upper fixed shaft 5 inserted into the elongated hole 12. As shown in FIGS. 3 to 5, when the fall prevention device 4 rotates 90 ° clockwise with respect to the leg 2 of the ladder main body 1, as shown in FIGS. The one end 14A of the elongated hole 14 formed in the other end 11B of the lower end 11B collides with the fixed shaft 15 in the lower part. As a result, further rotation of the connecting member 9 from the horizontal state in the clockwise direction is prevented, so that the fall prevention device 4 is held in the horizontal state.

1 and 2 in a normal state.
As shown by the solid line in FIG.
Since it is installed horizontally so as to cover the opening of 8,
Even when the lid 19 provided at the opening of the manhole 18 is removed when repairing or inspecting the water tank 16 or the like, there is no possibility that the lid 19 may fall accidentally into the water tank 16 from the opening.

Next, when entering the water storage tank 16 or the like from the opening of the manhole 18, the fall prevention device 4 in a horizontal state shown by a solid line in FIGS. Is lifted upward, as shown in FIG. 4, along the long hole 14 while being guided by the lower fixed shaft 15 fitted in the long hole 14 formed in the other end portion 11B of the holder member 11. From one end 14A side to the other end 14B
The holder member 11 rotates in the counterclockwise direction together with the connecting member 9 that moves in the lateral direction and rotates about the upper fixed shaft 5 as a center of rotation and the fall prevention tool 4 integrated therewith.

When the fall prevention tool 4 is rotated to the vertical position as shown by the dashed line in FIG. 6, the fall prevention tool 4 is attached to the connecting member 9 by its own weight, as shown in FIGS. It descends along the formed long hole 12, and the concave groove 13 formed on the distal end surface of the connecting member 9 is fitted to the lower fixed shaft 15 immediately below it. Thereby, the fall prevention device 4
Is fixed in this vertical state, and most of the fall prevention tools 4 vertically project upward from the opening of the manhole 18.

Therefore, the operator grasps the upper end portion of the outer frame member 6 of the fall prevention device 4 protruding upward from the opening of the manhole 18 and the lattice constituting member 7 installed in the outer frame member 6 and the like, and holds the body. While supporting, one foot can be put in the manhole 18, and the foot can be sequentially put on the cross rail 3 of the ladder main body 1 which is continuous below the fall prevention device 4, and can descend into the water storage tank 16 along the ladder main body 1. When the opening of the manhole 18 is closed with the lid 19 after the inspection work, etc., the fall prevention device 4 in the vertical state is lifted upward, and the concave groove 13 formed on the distal end surface of the connecting member 9 and the lower portion are formed. When it is turned clockwise after the connection with the shaft 15 is released, as described above,
Is fixed in a horizontal state again, and is set in a horizontal state in which the opening of the manhole 18 can be closed by the lid 19.

[0018]

As described above, the ladder with a fall prevention device for a manhole according to the present invention has a vertical ladder near the upper ends of both legs of a ladder main body fixed almost vertically to a water storage tank or the inner wall surface of the manhole. When the two fixed shafts are provided apart from each other, the lower fixed shaft is connected to an elongated hole formed in the connecting member of the fall prevention tool which is installed in the upper portion of the manhole opening.
One end is inserted through an elongated hole formed at the other end of the holder member rotatably mounted on the connecting member, and the fall prevention device is rotatable with respect to the two legs and fixed by a fixing means. It is configured to be fixed vertically and horizontally respectively, so when inspecting or repairing the water tank etc., when the manhole cover is opened, even if the inspector / repairer accidentally falls down from the opening of the manhole, a fall prevention device And can be prevented from falling to the lower part. Also, when descending down the ladder, the fall prevention tool stands up in a state protruding above the opening of the manhole, so that the inspector / repairer can easily descend the ladder. In addition, when the inspector / repairer lifts the fall prevention device upward with one hand during the descent and releases the fixing means, the fall prevention device rotates until it is perpendicular to the ladder main body and is fixed at that position. -There are various effects such that a person who looks into the repair can be prevented from falling by mistake.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a use state of a ladder with a fall prevention device for manhole according to the present invention.

FIG. 2 is a perspective view illustrating the operation of a fall prevention device in an opening of a manhole.

FIG. 3 is a partial perspective view in which a part of a ladder with a fall prevention device for manholes is omitted.

FIG. 4 is a partial side view of a main part for describing an operation.

FIG. 5 is a sectional view taken along the line II-II in FIG. 4;

FIG. 6 is a partial side view of a main part for describing an operation.

7 is a sectional view taken along line III-III in FIG. 6;

[Explanation of symbols]

 A Ladder with fall prevention device for manhole 1 Ladder main body 2 Legs 2A Upper end 3 Side rail 4 Fall prevention device 5 Upper fixed shaft 6 Outer frame member 6A arc portion 7 Grid component 8 Fall prevention device main body 9 Connecting member 10 Shaft Reference Signs List 11 holder member 11A one end 11B other end 12 long hole 13 concave groove 14 long hole 14A one end 15 lower fixed shaft 16 water storage tank 17 anchor 18 manhole 19 lid

Claims (5)

[Claims] An upper and lower fixed shaft is provided near an upper end of both legs of a ladder main body fixed substantially perpendicularly to an inner wall surface of a water tank or the like or a manhole thereof. The lower fixed shaft is formed in the elongated hole formed in the connecting member of the fall prevention device installed in the opening of the manhole at the other end of the holder member one end of which is rotatably mounted on the connecting member. A fall prevention device for a manhole, wherein the fall prevention device is rotatable with respect to the two legs and fixed vertically and horizontally by fixing means, respectively. ladder. 2. When the fall prevention device is in a vertical state, a concave groove formed in the distal end surface of the connecting member engages with a lower fixed shaft, and when in a horizontal state, one end surface of a long hole formed in the other end of the holder member. 2. A ladder with a fall prevention device for a manhole according to claim 1, wherein the fixing means has a configuration in which it abuts against the lower fixed shaft. 3. The manhole fall prevention device according to claim 1, wherein the area of the fall prevention device is slightly smaller than the area of the opening of the manhole, and a part of the outer frame is formed by an arc. Attached ladder. 4. The ladder with a fall prevention device for a manhole according to claim 1, wherein the fall prevention device is in a lattice shape, a grating shape, or a net shape. 5. The ladder main body of a ladder with a fall prevention device for manhole according to claim 1, 2, 3 or 4, wherein the fall prevention device is installed in an opening of the manhole when the fall prevention device is fixed in a horizontal state. A manhole fixed to a water storage tank or the like or to the inner wall surface of the manhole so as to be located slightly below the position of the lid.