JPH053678Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a flexible ladder whose steps can be fixed at any desired position.

(Prior Art) Various types of ladders are currently used for climbing up and down walls. That is, a so-called ladder as shown in FIG. 11 is fixed to a wall surface at both upper and lower ends, or in the case of a concrete wall, a foothold as shown in FIG. 12 is used.

For emergency use, there is also a rope ladder as shown in Figure 13.

(Problem that the invention seeks to solve) However, the steps of these ladders are generally fixed and cannot be moved. However, depending on the situation at the site, a request to move the position of the step often occurs. There are also many requests to carry and install the ladder at any location. However, in the case of a ladder like the one shown in FIG. 11, since the step 1a is fixed to the supporting columns 2 on both sides, it is impossible to change its position.
Furthermore, since the step 1a and the support columns 2 on both sides are integrated, the volume and weight are large, making it inconvenient to transport. Since the footrest shown in FIG. 12 is embedded in the wall 4 from the beginning with the legs 3 fixed to the step 1b, there is almost no freedom of movement.

Also, a rope ladder like the one shown in Figure 13 is the easiest to move. Although adjusting the position of the step 5 is somewhat complicated, it is possible to change the position where the step 5 is fixed to the rope 6 by retying the knot on the rope 6, for example. However, rope ladders are generally only fixed at the top and are an unstable means of climbing, so they can only be used for emergencies.

The present invention was made in order to obtain a ladder that can adjust the step position arbitrarily, is simple and movable, and can be securely fixed once installed, making it convenient for ascending and descending.

(Means for Solving the Problems) As a means for solving the above-mentioned problems, the present invention provides a foothold step having a conical hole whose diameter increases downward in the vertically extending rail. A conical wedge member made of plastic or metal with a split is interposed between the rail and the step for a footrest, and is installed in a loosely fitted state, and further provided on the lower surface of the step for the footrest. A wedge receiver with an L-shaped cross section is provided around the periphery of the hole.

(Function) In the ladder of the present invention, the step is fitted onto the rail with some play, and the step is moved and adjusted along the rail to the desired mounting position, and then a conical wedge member is inserted between the step and the rail. By press-fitting, the step can be securely fixed in that position.

During use, when a person's weight is applied to the step, a stronger wedge force is generated, which advantageously increases the adhesion of the step to the rail.

Furthermore, if it is desired to change the mounting position of the step, the step can be moved to an arbitrary position along the rail by tapping the wedge member downward to release the fixing force of the step. Therefore, the step spacing and height position can be freely adjusted depending on the installation location of the ladder, the physique of the intended user, etc., and is extremely versatile.

(Example) Examples of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment in which the present invention is applied as a footrest for lifting the inner wall of a manhole.
It is fixed to the manhole wall 12 by a fixing means to the manhole wall 12. A footrest step 13 made of resin and having a hole 14 in the center is fitted into the rail 11. The shape of the hole 14 of the footrest step 13 is similar to that of the second
As shown in the figure, it is formed into a conical shape whose diameter expands downward. In the space between the conical inner surface of the hole 14 and the rail 11, a conical wedge member 15 with a split is inserted. Wedge member 15 can be constructed of plastic or metal. In this embodiment, the conical wedge member 15 is made up of three members equally divided at an angle of 120°, and in order to prevent the wedge member 15 from falling downward during installation and removal, the step 13 is There are three wedge receivers 16 with an L-shaped cross section on the periphery of the hole 14 provided on the lower surface.
Individually fixed. The wedge receiver 16 is made of an elastic material, and its tip side can be bent outward. (See Figures 3 and 4) To further describe the step 13, as shown in Figure 5, both sides of the step 13 are bent toward the manhole wall 12, and the tips of the bent portions abut against the manhole wall 12. Usually used. A finger hook 13a is formed on the outer peripheral surface of the intermediate portion of the step 13, and a non-slip pattern is arranged on the entire surface. Also, step 13
A concave groove 13c is provided on the upper surface of the housing to discharge foreign matter such as dust and moisture.

Next, regarding the top and bottom steps 23, they are different in configuration from the other intermediate steps 13, and are integrally formed with a mounting part 23a that extends perpendicularly from the center of the step 23 to the manhole wall 12. The mounting part 23a may penetrate the manhole wall 12 and be fastened and fixed by screwing a nut into the threaded part at the tip end. The fixing means for the mounting part 23a is not limited to the nut fastening method, but may be an embedding method.

To attach the foothold step 13 to the rail 11, move the step 13 vertically to the appropriate position, and at that position push up the conical wedge member 15, which is split into three parts, upward at once. and press fit into the inner surface of the conical hole 14 of the step 13. Once the conical wedge member 15 is press-fitted into the foothold step 13, the conical wedge member 15 is tightly tightened so that the step 13 will not move from its position unless a significant upward force is applied to the step 13. . In addition, if the worker's weight is applied to the footrest step 13, the conical wedge member 1
5 is tightened even more strongly.

When moving the position of the footrest step 13, the step 13 may be lifted by lightly tapping it upward. Then, the conical inner surface of the hole 14 of the footrest step 13 separates from the conical wedge member 15, and the force that had been tightening the rail 11 is released.
The conical wedge member 15 becomes free and is in the state shown in FIG. The bottom view is shown in FIG. The conical wedge member 15 is also moved upward by being hooked to the wedge receiver 16 fixed to the lower surface of the step 13. If the footrest step 13 is slowly moved downward in this state, the conical wedge member 15 can be moved to any point below without being tightened.

In this embodiment, the conical wedge member is divided into three parts, but the number of divisions may be any number, for example, one or two. 1
"Piece" means a C-type with a break in one place. FIG. 6 shows a C-shaped wedge member 15a, in which 15b are vertical grooves formed at 90° pitches on the inner surface. In this case, it is necessary to use a conical wedge made of a material with an extremely small elastic modulus, such as resin, and with an open mouth when the conical wedge is in a free state.

FIGS. 7 and 8 are cross-sectional plan views of the rail 11 according to another embodiment of the present invention. In FIG. 7, the footrest step 17 is bent into a dogleg shape, and is suitable for the inner wall of a manhole with a small diameter. Further, FIG. 8 shows one having a footrest step 18 on only one side. In this type, vertically adjacent steps 18 are installed by arranging them alternately on the left and right in opposite directions. A large diameter portion 18a for preventing slipping is formed at one end of the step 18.

FIG. 9 shows a bar-shaped footrest step 19 extending in a straight line on both the left and right sides of the rail 11. Also the 10th
The figure shows an arcuate footrest step 20 with both sides bent toward the manhole wall 12.

The shapes of the footrest steps 17, 18, 19, and 20 shown in FIGS. 7 to 10 are merely examples, and various shapes are possible.

(Effects of the Invention) Since the present invention has the above-described configuration and operation, the position of the footrest step can be freely set to any vertical position while the ladder is installed. In addition, the rail and footrest step can be transported in a detached state and installed and assembled on site, making it easy to handle. Furthermore, once the wedge member is press-fitted and attached, it is securely fixed, and when the weight is applied during use, a larger wedge effect is created, making it convenient to go up and down, and fully functioning as a ladder. Moreover, even after installation, the position of the step can be easily changed by simply removing the wedge member, and since a wedge receiver is provided, the conical wedge member will not fall off and be lost. As described above, it is possible to provide a ladder that has a simple structure, is convenient to handle, and has unique practical value due to its high flexibility as a ladder that can be installed in a place with a narrow space.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the whole ladder of the present invention, Fig. 2 is a cross-sectional view when the footrest step is fixed to the rail, and Fig. 3 is a cross-sectional view when the ladder is not fixed to the rail. Figure 4 is a bottom view of the step in Figure 3, Figure 5 is a top view of the step in Figure 1,
FIG. 6 is a perspective view of the wedge member forming one C-shape, FIGS. 7 to 10 are plan views of other embodiments, and FIGS. 11 to 13 are of the prior art;
Figure 1 is a perspective view of an ordinary ladder, Figure 12 is a perspective view of a foothold on a concrete wall, and Figure 13 is a perspective view of a rope ladder. 11...Rail, 13...Step for footrest, 1
4... Conical hole, 15... Conical wedge.

Claims (1)

[Scope of utility model registration request] A footrest step having a conical hole whose diameter increases downwardly is loosely fitted to a rail extending vertically, and a slotted plastic is installed between the rail and the footrest step. or by interposing a conical wedge member made of metal,
Furthermore, the adjustable ladder is characterized in that a wedge receiver having an L-shaped cross section is provided on the periphery of the hole provided on the lower surface of the foothold step.