JPH0532639Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention relates to a movable ladder that can be extended and contracted to be used at appropriate locations, such as for going up and down underground holes.

(Prior Art) A movable extendable ladder for climbing up and down underground holes such as manholes is composed of a fixed part ladder and a movable part ladder.
A supporting body or a connecting body that slidably supports the movable part ladder is provided on the fixed part ladder, and the movable part ladder is slid and the engagement groove at the lower end of the movable part ladder is fitted into the upper step of the fixed part ladder. The lower part of the part ladder is fixed to the upper part of the fixed part ladder, and the movable part ladder is made to protrude from the upper end of the fixed part ladder.

(Problem that the invention aims to solve) However, this fixing work with the movable part ladder in the extended state requires that the worker lift the movable part ladder by hand and engage the lower end of the movable part ladder with the upper step of the fixed part ladder. It is extremely time-consuming and complicated work to fit into the matching groove.

(Means for Solving the Problems) Therefore, the present invention provides a movable ladder that makes it extremely easy to extend, contract, and fix the movable part ladder to the fixed part ladder, thereby improving workability.

The structure of this invention consists of a fixed part ladder that is fixed to an appropriate location, and a movable part ladder that is supported slidably in the longitudinal direction inside this fixed part ladder, and the steps of the fixed part ladder are lower than the movable part ladder. A long groove opened at the front is provided in the lower side pillars of the movable part ladder provided at the front, and a hook that can be freely stored in the long groove and whose free end can freely protrude outward from the long groove opening is pivotally supported. The free end of the hook is provided with an engaging groove that can be freely engaged with a predetermined step of the fixed part ladder, and the free end of the hook is always biased so as to protrude obliquely downward from the front surface of the movable part ladder. A projecting body is provided on the movable part ladder to freely protrude into the movable part ladder and engages with a stop fitting provided on the back surface of the fixed part ladder at a position where the free end of the hook hooks on the step of the fixed part ladder. , this projecting body is provided so that it is constantly projected by the ammunition.

(Function) In the movable ladder of this invention, the movable part ladder is slidably supported on the fixed part ladder, the movable part ladder can be stored inside the fixed part ladder, and the movable part ladder can be pulled up from the fixed part ladder and fixed. The lower part of the movable part ladder can be locked and fixed to the upper part of the part ladder.

When pulling up this movable ladder, hooks protrude from the lower front surfaces of both columns of the movable ladder.
This corresponds to each step of the fixed part ladder, and at this time each hook rotates against the force of the bullet and enters each long groove of each side post, allowing the hook to pass through each step. Furthermore, when the protruding body of the movable part ladder is engaged with the stopper of the fixed part ladder, the operator feels resistance, and in this position the free end of each hook of the movable part ladder is pulled to a predetermined step of the fixed part ladder. I can see that it is in a stuck state. Therefore, when the operator pulls down the movable part ladder from this position, the hooks on both sides fit into the engaging grooves of each hook on both sides of a predetermined step of the fixed part ladder. As a result, the movable part ladder is fixed to the fixed part ladder in an extended state. In addition, in order to store the extended and fixed movable part ladder into the fixed part ladder, the operator must pull up the movable part ladder with some force, and the protrusion that is locked to the stop fitting will move into the movable part ladder. When retracted, the movable ladder is pulled up and each hook is removed from its predetermined step.
When the movable ladder is lowered from this state, each hook resists the force of the bullet at each step and enters each long groove of each side column, allowing it to pass through each step. Also, the projecting body is retracted into the movable part ladder at the stop metal fitting location as described above.

(Example) An embodiment of this invention will be described below with reference to the drawings.

1 is a fixed part ladder vertically fixed to the side wall 3 of an entrance/exit 2 of an underground hole, etc.; 4, 4... are supports supporting this fixed part ladder 1 at a distance from the side wall 3; 5, 5;
are the pillars on both sides of the fixed part ladder 1, and each of these side pillars 5 is made of a square piece having a constant width from front to back. 6,
6, 6... are round bar-shaped steps spread approximately horizontally at a constant interval between these pillars 5, 5 on both sides,
Each of these steps 6 is located at the front of each side post 5. 7, 7 are U-shaped stop fittings provided on the back of each side pillar 5, 5 at the top of this fixed part ladder 1;
This stopper fitting 7 has one side of the U-shape attached to each side post 5.
A U-shaped groove is formed inside each side column 5, and a U-shaped bottom plate is formed such that the lower side approaches the side column 5 and the upper side approaches the side column 5, as shown in FIG. It is tilted away from the Reference numerals 8 and 8 denote guide support pieces having a key-shaped cross section provided on the inside of the upper end of each side column 5, 9 a guide bar passed between each of the back surfaces of the side columns 5 and 5 at eight locations on each of these guide support pieces, and 10 a guide support piece provided at the inner side of the upper end of each side column 5; Between this guide bar 9 and each guide support piece 8 and step 6
and a movable part ladder in which rectangular cylinder side columns 11 on both sides are slidably inserted and supported between each of the above-mentioned stop fittings 7,
12, 12, 12...Round bar-shaped steps extending approximately horizontally between the square tube side columns 11, 11 on both sides of the movable part ladder 10, 13, 13 are the respective square tube side columns 1
The vertical long holes 14, 14 provided in the lower front surface of 1 are hooks rotatably supported by a shaft 15 in each of these long holes 13. and can be stored freely at the bottom,
Moreover, its free end can freely protrude outward from each rectangular tube side column 11 from the elongated hole 13. 16 is each of these hooks 1
The lower part of the opening of each of these engaging grooves 16 forms the long piece 14a of the hook 14, and the upper part of the opening forms the short piece of the hook 14. 14b. Reference numeral 17 denotes an arc-shaped spring plate provided inside each square-tube side column 11 with the center portion fixed to the inner wall of the back plate of the square-tube side column 11 behind each of these hooks 14; consists of two spring plates, both ends of which are close to the elongated hole 13, and restrict the rotation of the hook 14. 1
8 is each rectangular cylinder side pillar 11 on both sides of this movable part ladder 10
Stopper screw protruding rearward from the back of the lower end, 1
Reference numeral 9 indicates a through hole bored in the back plate of each rectangular tube side column 11 above each of these stopper screws 18, and 20 indicates a through hole bored into the back plate inner wall of each rectangular tube side column 11, with one end fixed to the root of each of the above-mentioned stopper screws 18. The overlapping spring plates 21 are spherical protrusions fixed to the free ends of each of these spring plates 20, and each of these spherical protrusions 21 loosely fits into each of the through holes 19, and each of the square tube side columns 11 It protrudes backward from the back. Reference numeral 22 denotes a stopper provided on the upper end side surface of one of the rectangular tube side pillars 11 of the movable part ladder 10. When the movable part ladder 10 is housed in the fixed part ladder 1, this stopper 22 stops the fixed part ladder 1. The movable part ladder 10 is supported by the fixed part ladder 1 at the upper end of one of the side columns 5. Reference numeral 23 denotes a pipe-shaped grouper stand provided on the upper end side surface of the other rectangular tube side column 11 of the movable part ladder 10, and this grouper stand 23 also serves as a stopper like the stopper 22 described above.

In this embodiment, when the movable ladder is not needed, the movable part ladder 10 is superimposed on the fixed part ladder 1 inside the entrance/exit 2 of an underground hole or the like, as shown in FIGS. 1 and 2. When a worker ascends or descends this entrance/exit 2, a movable ladder 10 is used as shown in FIGS. 3 and 4.
Extend it and fix it so that it protrudes about 80cm from the ground surface.

When the movable part ladder 10 is pulled up to extend from the overlapping state of the movable part ladder 10 and the fixed part ladder 1, each hook 14 located below the movable part ladder 10 in the overlapping state is moved by its own weight to each rectangular tube side column. However, as shown in FIG.
Its free end protrudes downward and outward from the
As shown in FIG. 9, when passing through each step 6 of the fixed part ladder 1, the hook 1 is pulled up against the force of the arcuate spring plate 17 by the lifting force (arrow A) of the movable part ladder 10.
4 rotates clockwise around the shaft 15 as shown by the arrow B, and enters into each square tube side column 11. After passing through each step 6, the hook 14 rotates counterclockwise in FIG. The upper piece springs back, and its free end hangs diagonally downward again, protruding outward from the square cylinder side column 11. These steps are repeated at each of the six steps, and when the hook 14 reaches the six highest steps of the fixed part ladder 1, the hook 14 is moved by the force of the lower piece of the arcuate spring plate 17, as shown in FIG. It tries to rotate counterclockwise around the shaft 15, but
At the point where the long piece 14a of the hook 14 is hooked on the step 6, the spherical protrusion 21 protruding from the lower back surface of the movable section ladder 10 hits the lower side of the stop fitting 7, preventing the movable section ladder 10 from being pulled up. be done. As a result, the operator can hold the long side 14a of the hook 14.
It turns out that the hook 14 is hooked on the topmost step 6, and if the movable part ladder 10 is pulled down as it is (arrow C), the hook 14 will be attached to its long side 14a.
The engagement groove 16 fits into the step 6 while being guided by the step 6.
As a result, each hook 14 fits into the uppermost step 6 as shown in FIGS. 5 and 6, and the movable part ladder 1
0 is fixed in the extended state.

In order to overlap and store the movable part ladder 10 on the fixed part ladder 1 from this state, as shown in FIG. Spherical body 21
is retracted into each square cylinder side column 11, and each stop fitting 7
, and each hook 14 is removed from the top step 6. When the movable part ladder 10 is pulled down from this state, each hook 14 resists the force of each arcuate spring plate 17 at each step 6 and enters each rectangular tube side column 11, and after passing each step 6, moves to each rectangular tube side. The pillar 11 is projected outward and this process is repeated. Further, each spherical protrusion 21 is guided by the inclined bottom plate of each stop fitting 7, and smoothly retracts into each rectangular cylinder side column 11 without any impact, and passes through each stop fitting 7 at seven locations. In this way, the movable part ladder 10 is superimposed and stored in the fixed part ladder 1,
The state will be as shown in FIGS. 1 and 2.

In the above embodiment, both side columns of the movable part ladder are square tubes, so that the hook can be stored in the square tube side columns, but the present invention is not limited to this. Any material with long grooves may be used. Further, in the above embodiment, the hooks on both sides of the movable part ladder are fitted to the top step of the fixed part ladder, but the hooks are not limited to this, and may be fitted to predetermined steps. Furthermore, the movable ladder of this invention can be used not only in underground holes but also in other suitable locations.

(Effects of the invention) This invention has the above-mentioned configuration, and in order to extend and fix the movable part ladder that is overlapped and housed in the fixed part ladder, the operator only has to pull up the movable part ladder. When the free ends of the hooks on both sides of the movable section ladder are hooked onto the predetermined steps of the stationary section ladder,
Because the projecting body of the movable part ladder is locked to the stop metal fitting of the fixed part ladder, the operator will feel some resistance to pulling up the movable part ladder, and when the movable part ladder is pulled down at this position, the operator will automatically The engaging grooves of the hooks on both sides fit into the predetermined steps, and the movable ladder is fixed. In addition, in order to store the extended movable part ladder in the fixed part ladder, the operator should pull up the movable part ladder a little forcefully, and the engagement grooves of each hook will automatically disengage from the predetermined steps, and the movable part will remain in place. You can lower the ladder.

Therefore, the operator can very easily extend, contract, and fix the movable ladder of this invention. Therefore, it does not require any skill and can be operated by anyone.

[Brief explanation of the drawing]

The figures show an embodiment of this invention. Fig. 1 is a front view showing the movable part ladder of this invention stored in a fixed part ladder, Fig. 2 is a sectional view taken along line A-A in Fig. 1, and Fig. The figure is a front view showing the movable part ladder of this invention extended and fixed with respect to the fixed part ladder, Figure 4 is a sectional view taken along line B-B of Figure 3, and Figure 5 is a front view of the main part of this invention. Fig. 6 is a partially cutaway side view of the same part, Fig. 7 is a sectional view taken along the line C-C of Fig. 5, and Fig. 8 is a sectional view taken along the line D-- Fig. 6 of Fig. 6.
9 is a partially broken side sectional view showing a state in which the movable part ladder of this invention is pulled up, and Fig. 10 is a sectional view of the movable part ladder of this invention in which the projecting pair is a stopper for the fixed part ladder. FIG. 11 is a partially cutaway side sectional view showing the movable part ladder of this invention in a state where it is further pulled up from the fixed part ladder from the state shown in FIG. 10. In the figure, 1 is a fixed part ladder, 5 is a side column, 6 is a step, 7 is a stopper, 8 is a guide support, and 10
11 is a movable part ladder, 11 is a square cylinder side column, 12 is a step, 13 is a long hole, 14 is a hook, 16 is an engagement groove,
17 is an arcuate spring plate, and 21 is a spherical protrusion.

Claims (1)

[Scope of utility model registration request] It consists of a fixed part ladder that is fixed to an appropriate location, and a movable part ladder that is supported inside the fixed part ladder so as to be slidable in the longitudinal direction.The steps of the fixed part ladder are provided in front of the movable part ladder, and A long groove opening in the front is provided in the lower side pillars of the ladder, and a hook that can be freely stored in the long groove and whose free end can protrude outward from the long groove opening is pivotally supported. A lockable engagement groove is provided at a predetermined step of the fixed part ladder, and a bullet is provided in this long groove, which is biased so that the free end of the hook always protrudes diagonally downward from the front surface of the movable part ladder. , a projecting body is provided on the movable part ladder so as to be able to protrude freely and engages with a stop fitting provided on the back surface of the fixed part ladder at a position where the free end of the hook hooks on the step of the fixed part ladder; A movable ladder characterized by being provided with a projector so that it always protrudes.