JPH11350860A - Ladder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a worker climbing a ladder from dropping off by providing a ladder part and ropes attached to an upper portion of the ladder part at its one end while to a lower portion thereof at the other end. SOLUTION: After a ladder 10 is installed in a working site, a worker connects one end of a falling preventing device used at the work at a high place to a safety belt wound around his/her waist. The other end thereof is connected to a rope 42 of the ladder 10 via a connector. In the case where the worker is liable to fall during operation at an upper part of the ladder 10, the conenctor is abruptly pulled along the rope 42 by the worker tending to fall. However, the conenctor does not follow the abrupt movement and made stationary to the rope 42 since it is locked thereto, and the worker is suspended in the air, thereby preventing the falling.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ladder, and more particularly, to a ladder capable of preventing a falling worker from falling.

[0002]

2. Description of the Related Art When working at heights, workers
Work with a lifeline. However, the worker was unable to attach a lifeline while climbing the ladder.

[0003]

For this reason, the conventional ladder has a problem that a worker may lose his balance due to shaking of the ladder or the like during climbing up and down, and may fall from the ladder.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a ladder that can prevent a falling worker from falling.

[0005]

A ladder according to the present invention has been made to achieve the above object, and comprises a ladder portion,
One end is provided at an upper portion of the ladder portion, and the other end is provided at a lower portion of the ladder portion.

According to such a configuration, the rope extends from the upper part to the lower part of the ladder along the longitudinal direction of the ladder. Therefore, by connecting the lifeline to this rope via a connector that prevents rapid movement along the rope but allows slow movement, the worker can maintain the lifeline while climbing and lowering the ladder. Can be attached, and the vehicle does not crash during climbing up and down the ladder. Further, when performing the work while riding on the ladder, the worker can perform the work without changing the lifeline.

As a device provided with this type of coupler, there is a well-known fall prevention device used for work at height such as assembling a steel tower. In this fall prevention device, a hook is attached to one end of a lifeline, and a coupler is attached to the other end. This coupler is connected to a rope fixed to a work place at a high place, and moves along the rope following slow movements such as when the worker moves along the rope, but the worker falls down It is a coupler that does not follow sudden movements such as when it is locked and is locked to the rope.

In practicing the present invention, when the ladder portion is stretchable, it is preferable that the length of the rope can be changed according to the extension and contraction of the ladder portion.

According to such a configuration, the rope does not hinder the expansion and contraction of the ladder portion, and the rope does not loosen.

In carrying out the present invention, the ladder is
It is preferred to have a configuration with a length adjuster attached to one end of the rope.

According to such a configuration, the length of the rope can be adjusted to a length adapted to the length of the ladder portion by the adjuster.

In practicing the present invention, a configuration may be employed in which a bent portion is provided at the upper end of the ladder portion. The bent portion is preferably formed by bending an upper end portion of a column constituting the ladder portion in a depth direction, that is, a front direction as viewed from a worker riding the ladder in a normal posture.

According to such a configuration, since the upper end of the ladder is bent in the depth direction, when the ladder leans against the tree, the bent portion has a large angle with respect to the tree trunk. Will be. Therefore, the upper end of the ladder is less likely to come off the tree trunk, the stability of the upper part of the ladder is increased, and the ladder is prevented from falling in the lateral direction (left and right directions as viewed from the operator).

In practicing the present invention, it is preferable that a belt is provided on the ladder portion.

According to such a configuration, the ladder can be fixed to the tree, telephone pole or the like on which the ladder is leaned by the belt, and the ladder falls down in the vertical direction (in the front-rear direction of the worker). Is prevented. Further, since the ladder can be fixed to a tree or the like, there is no need for a lower worker to hold the ladder on the ground. As a result, labor saving is achieved by reducing the number of workers while maintaining safety, and the possibility that lower workers are injured by falling objects from above is eliminated.

In practicing the present invention, it is preferable that a retractable stone protruding portion is provided at the lower end of the ladder portion.

According to such a configuration, the ladder is stabilized by piercing the stone ram into the ground, and the ladder is prevented from tipping over.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. The drawings merely schematically show the sizes, shapes, and arrangements of the components so that the present invention can be understood. Therefore, the present invention is not limited to the embodiment shown in the drawings.

FIG. 1 is a schematic front view showing a ladder 10 according to an embodiment of the present invention in an extended state.
Is a side view thereof. FIG. 3 is a schematic side view in a state where the ladder 10 is contracted.

As shown in FIGS. 1-3, the ladder 10 includes a ladder portion including an upper portion 12 and a lower portion 14 made of an aluminum alloy. In addition, the upper part 12 and the lower part 14 may be comprised by other metals or materials.

The upper part 12 includes a pair of columns 16 and 18.
And a plurality of crossbars 20. Each strut 16, 18
Have a length of about 450 cm and are spaced apart by a predetermined distance and arranged in parallel. Each crossbar 20 is arranged at a fixed interval, and connects the left and right columns 16 and 18.

The lower portion 14 includes a pair of columns 22, 24.
And a plurality of crossbars 26. Each strut 22, 24
Have a length of about 450 cm and are spaced apart by a predetermined distance and arranged in parallel. Each crossbar 26 is arranged at a fixed interval, and connects the left and right columns 22, 24.

The upper portion 12 and the lower portion 14 having such a configuration are combined with each other so as to be slidable in the longitudinal direction. Therefore, the ladder 10 is made to slide in the upper portion 12 and the lower portion 14 like the conventional so-called double ladder, so that the ladder 10 is in the extended state shown in FIGS. 1 and 2 and the contracted state shown in FIG. The configuration is such that the length of the ladder portion can be changed between the states.

Further, the ladder 10 is configured so that the upper portion 12 and the lower portion 14 can be fixed at a desired relative position by a stopper mechanism (not shown), similarly to the conventional double ladder.

The upper end portions 16a and 18a of the columns 16 and 18 of the upper portion 12 are bent in the depth direction, that is, in the front direction as viewed from a worker riding on a ladder in a normal posture to form a bent portion. In this embodiment, the angle of the fold is about 45 degrees and the folded upper end portion 16
The length of a, 18a is about 40 cm.

The upper end portions 16a, 18a will have a large angle to the tree trunk when the ladder 10 is leaned against the tree trunk. That is, the upper end portions 16a, 18
"a" is arranged across the trunk while intersecting the trunk at a deep angle. Therefore, the upper end of the ladder 10 is less likely to come off the tree trunk, the stability of the upper part of the ladder is increased, and the ladder is prevented from falling in the lateral direction (left and right directions as viewed from the operator).

FIG. 4 is a plan view of the ladder 10 and the ladder 1.
0 indicates the upper end portion. As shown in FIG. 4, from the rung 20 located at the top of the ladder 10, the ladder 1
Bars 28, 30 extending diagonally toward the 0 bent upper end portions 16a, 18a are attached.

Further, an elastic belt 32 is attached to the upper end portion 18a. Belt (band) 32
Is made of cloth. For example, a hook is provided at the tip, and after winding the belt 32 around a tree, a telegraph pole, or the like, the hook is hooked on the other upper end portion 16a, so that the upper part of the ladder 10 and the tree And so on. Therefore, when the ladder 10 is leaned against a tree, a telephone pole, or the like, the belt 32 is wound around the tree or the like so that the upper portion can be fixed to the tree or the like. The connection between the belt and a tree may be performed by another method.

As shown in FIG.
A U-shaped bracket 34 is attached to an outer position of the upper part of the left support column 16 of FIG. The U-shaped fitting 34 is attached to the support 16 by fixing both ends to the support 16. The mounting position of the metal fitting 34 is near the base end of the bent upper end portion 16a.

A U-shaped fitting 36 is attached to an outer position below the lower column 22 of the lower portion 14. The U-shaped bracket 36 is attached to the column 22 by fixing both ends to the column 22 in the same manner as the bracket 34 attached to the upper portion 12.

At the lower ends of the struts 22 and 24 of the lower portion 14, retractable stone protruding portions (earth protruding portions) 37 and 38 are provided.
Are provided, respectively. Stone bumps 37, 38
Is made of metal, and its tip has a tapered shape so that it can pierce the ground. Stone butt 3
Reference numerals 7 and 38 denote projecting positions (FIGS. 1 and 2) in which the distal end portions protrude from the distal ends of the columns 22, 24, and retracted positions (FIG. ) Is configured to be movable.

Steps 37a, 38a extending outward are formed on the other ends of the stone protrusions 37, 38, respectively. The stone bumps 37, 38
It is configured such that the tip portion can be easily pierced into the ground by stepping on the a and 38a with the foot.

Further, as shown in FIGS. 1 to 3, a stretchable belt (band) 40 is attached to the column 24 of the lower portion 14. The belt 40 is made of cloth, for example, provided with a hook at the tip. After winding the belt 40 around a tree, a telephone pole, or the like, the hook is hooked to the other column 22 of the lower portion 14. , The ladder 10 and a tree or the like can be connected. Therefore, when the ladder 10 is leaned against a tree, a telephone pole or the like, the belt 40 is wound around the tree or the like so that the lower portion can be fixed to the tree or the like. The connection between the belt and a tree may be performed by another method.

As shown in FIG.
Between the bracket 34 attached to the column 16 of the lower part 14 and the bracket 36 attached to the column 22 of the lower portion 14.
2 are arranged. The rope 42 is made of a synthetic fiber such as nylon and has a diameter of about 15 mm.
Has a length longer than the distance between the metal fittings 34 and the metal fittings 36 in the extended state shown in FIGS. 1 and 2.
The rope 42 is connected to a lifeline as described later, and therefore has a strength enough to withstand a load generated when the worker falls. Further, the rope 42 has a contraction adjuster 44 attached to one end and a hook 46 attached to the other end. In the ladder 10, the contraction adjuster 44 is connected to the fitting 36 via a carabiner 48,
The hook 46 is directly connected to the metal fitting 34. With this connection, the rope 42 is disposed between the metal fittings 34 and 36. The contraction adjuster 44 and the hook 46 are detachably connected to the metal fittings 34, 36, respectively. Therefore, the rope 42 can be easily attached to and detached from the ladder portion.

A contraction adjuster 44 is attached to one end of the rope to adjust the length of the rope. Therefore, in the ladder 10, the metal fittings 34 and 36
Is changed, the length of the rope 42 located between the fitting 34 and the fitting 36 can be changed according to the change in the length. As a result, regardless of the length of the ladder 10, the rope 42 is arranged without any slack between the bracket 34 and the bracket 36.

In the ladder 10 of this embodiment, a contraction adjuster “Flock” (trade name) manufactured by Fujii Electric Works, Ltd. is used.
It is used as a contraction regulator 42.

FIG. 5 is a schematic plan view of the contraction adjuster 44, and FIG.
8 is a schematic cross-sectional view of a contraction adjuster 44 to which the controller 8 is connected.

As shown in FIGS. 5 and 6, the contraction adjuster 44 includes a first member 440 and a second member 442. The first member 440 includes an opening 444 provided on one end side and a first key hole type opening 44 provided on the other end side.
6 and a pair of long holes 448 and 450 provided with the first keyhole type opening 446 interposed therebetween.

The second member 442 has an opening 452 provided at one end and a second key hole type opening 454 provided at the other end and having the same shape as the first key hole type opening 446.
And a pair of long holes 456 and 458 provided with the second keyhole type opening 454 interposed therebetween. Opening 4 of first member
The first key hole type opening 446 and the second key hole type opening 454 have dimensions that allow the rope 42 to be inserted.

The first member 440 and the second member 442 are overlapped in a state where the corresponding slots are aligned with each other, and bolts 460 and 462 are inserted into the slots so as to correspond to the length of the slots. , So as to be relatively movable in the longitudinal direction. The first key hole type opening 446 of the first member 440 and the second key hole type opening 454 of the second member 442 are formed so as to be able to take a completely aligned state and a state shifted from each other by this relative movement. Have been.

One end of the rope 42 is connected to a first member 44.
After the first member 440 is inserted through the opening 444 of the first
It is inserted through the keyhole type opening 446 and the second keyhole type opening 454 of the second member 442. As described above, the first member 4
40 and the second member 442.
The key hole type opening 454 is formed so as to be able to take a completely aligned state and a state shifted from each other by the relative movement of the first member 440 and the second member 442.
When the first key hole type opening 446 and the second key hole type opening 454 are completely aligned, the rope 42 can pass through the inside thereof. However, when the first key hole type opening 446 and the second key hole type opening 454 are displaced from each other, as shown in FIG. The rope 42 is sandwiched between the hole-shaped opening 454 and the rope 42 cannot move relative to the contraction adjuster 44.

Therefore, with the first key hole type opening 446 and the second key hole type opening 454 aligned, the rope 4
2 is moved relative to the contraction adjuster 44, and then the first key hole type opening 446 and the second key hole type opening 454 are shifted from each other, so that the length of the other end portion of the rope 42 is reduced. Adjustment is possible.

A carabiner 48 is connected to the opening 452 of the second member 442, and the contraction adjuster 44 is connected to the metal fitting 36 via the carabiner 48.

Next, a method of using the ladder 10 will be described. The ladder 10 is stored in a contracted state shown in FIG.
In this state, they are transported to the work site. Generally, the rope 42 is detached from the ladder portion and transported.

At the work site, the upper part 12 and the lower part 14 are slid to bring the ladder 10 to the required length. Next, the length of the other end portion of the rope 42 is set to be substantially equal to the distance between the metal fittings 34 and 36 by the shrinkage adjuster 44. Next, the rope 42 is attached to the ladder portion by connecting the hook 46 to the metal fitting 34 and connecting the shrinkage adjuster 44 to the metal fitting 36 via the carabiner 48.
As a result, the rope 42 is attached to the ladder portion in a state of extending without loosening along the columns 16 and 22 of the ladder 10.

Further, the ladder 10 is set up at a predetermined position. At this time, when working on trees, the ladder 10
The ladder 10 is stabilized by inserting the bent portion of the upper part 12 between tree branches and the like. Also, ladder 1
When the work is carried out by leaning 0 on a tree trunk or a telegraph pole, the tree trunk or the telegraph pole is arranged between the diagonally extending bars 28 and 30 provided at the top of the ladder 10, The upper part of the ladder 10 is stabilized.

In addition, stone butt parts (thrust parts) 37, 38
Steps 37a, 38a of the ladder 10 are stuck on the ground by stomping the tips of the stone protruding parts (earth protruding parts) 37, 38 into the ground to stabilize the lower part of the ladder 10.

If necessary, the ladder 10 is wound by winding an elastic belt 32 provided on the upper end portion 18a and an elastic belt 40 provided on the lower portion 14 around a tree trunk or the like. Stabilize.

After the ladder 10 is set in the work place in this way, the work is performed. An operator connects one end of a fall prevention device used in working at height to a safety belt wrapped around the waist. The other end of the fall prevention device is connected to the rope 42 of the ladder 10 via a coupler. The coupler allows for slow movement along the rope 42 but prevents rapid movement.

As this type of fall prevention device, there is a well-known fall prevention device used in high-place work such as assembling a steel tower or the like, for example, SS Rolip (trade name, manufactured by Fujii Electric Works Co., Ltd.). In this fall prevention device, a hook is attached to one end of a lifeline (childline) having a length of about 1 m, and a coupler is attached to the other end. The hook is connected to a safety belt wrapped around the worker's waist.

The coupler on the other end is connected to a rope fixed to a working place at a high place, and moves along the rope following a slow movement such as when an operator moves along the rope. However, it is a coupler that does not follow a sudden movement such as when the worker falls down, is locked to the rope, and does not move.

Therefore, the rope 4 is connected via this coupler.
When the worker with the lifeline connected to 2 moves up and down the ladder, the coupler moves along the rope 42. Therefore, the worker can move up and down the ladder without being obstructed by the lifeline.

On the other hand, if the worker is about to fall while moving up or down the ladder or working on the upper part of the ladder, the coupler is suddenly moved by the rope 4 by the worker who is about to fall.
It is drawn along 2. However, since the coupler does not follow the rapid movement and is locked to the rope, the worker who cannot move with respect to the rope 42 and is about to fall, becomes suspended and falls. Is prevented.

As described above, according to the ladder 10, it is possible to attach a lifeline even when the worker is moving up and down the ladder.
A crash can be prevented.

The present invention is not limited to the above-described embodiment, and various changes and modifications are possible within the scope of the matters described in the claims.

For example, the ladder 10 of the above-described embodiment
Is a stretchable ladder. The present invention is also applicable to a non-stretchable ladder.

[0057]

As described above, according to the present invention, there is provided a ladder capable of preventing a worker from falling during ascent and descent.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a state in which a ladder according to one embodiment of the present invention is extended.

FIG. 2 is a side view of the ladder of FIG. 1;

FIG. 3 is a schematic side view of the ladder of FIG. 1 in a contracted state.

FIG. 4 is a plan view of the ladder of FIG. 1;

FIG. 5 is a schematic plan view of a contraction adjuster.

FIG. 6 is a schematic sectional view of a contraction adjuster in which a carabiner and one end of a rope are connected.

[Explanation of symbols]

 10: Ladder 12: Upper part 14: Lower part 16, 18, 22, 24: Strut 20, 26: Crossbar 28, 30: Beam 32, 40: Belt 34, 36: Metal fitting 37, 38: Stone butt 42: Rope 44: Shrink adjuster 46: Hook 48: Carabiner

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshihiro Nagaoka 680-10 Toasa, Hakurai-cho, Yufutsu-gun, Hokkaido Hokkaido Expressway Muroran Branch Power Department (72) Inventor Katsuya Yamauchi 4-chome, Yoshino 4-jo Minami, Sunagawa-shi, Hokkaido 1 Inside the Sunagawa Electric Power Station, Sapporo Branch, Hokkaido Electric Power Co., Inc. (72) Kanae Yamaguchi 12-7-7-8 Misono, Toyohira-ku, Sapporo, Hokkaido Inside Yachiyo Industry Co., Ltd. (72) Kiyoshi Takamaru, Misono Toyohira-ku, Sapporo, Hokkaido Yachiyo Industry Co., Ltd. (72) Inventor Yoshiaki Yoneuchi 12-7-7-8 Misono, Toyohira-ku, Sapporo City, Hokkaido

Claims (6)

[Claims] 1. A ladder comprising: a ladder portion; and a rope attached at one end to an upper portion of the ladder portion and at another end to a lower portion of the ladder portion. 2. The ladder according to claim 1, wherein the ladder portion is extendable and retractable, and the length of the rope is changeable according to the extension and contraction of the ladder portion. 3. The ladder according to claim 2, further comprising a length adjuster attached to one end of the rope. 4. The ladder according to claim 1, wherein a bent portion is provided at an upper end of the ladder portion. 5. The ladder portion according to claim 1, wherein a belt is provided on the ladder portion.
The ladder according to the paragraph. 6. The ladder according to claim 1, wherein a retractable stone ram is provided at a lower end of the ladder.