JPH01310023A - Manufacture of step fitting - Google Patents

Abstract

PURPOSE:To improve productivity by folding a radial blade group and a calking hole at given intervals with a calking part projected to the both end surfaces of the rod material in which the bottom of a U-shaped part is made to a footstep surface, and making calking joining in the calking hole of a cylindrical body bendingly made by inserting the rod material. CONSTITUTION:A step 11 is flatly made with a press machine etc. to the bottom part of the U-shaped part of a U-shaped rod material 1, and the calking part 2 of a cylinder etc., having a smaller diameter and a shorter dimension than that of the material 1, is integrally performed to the both end surfaces of the material 1 by providing an antislipping projection. And a calking hole 33 is punched in the middle by punching the plate body of the cross plate 3 etc. having a blade member 31 group in radial by pressing, and a gap part is made to a slit end surface 32. And the outer periphery diameter of an anchor cylinder 34 is designed to have the same as the outer periphery of the material 1 by forming the cylinder 34 with the member 31 bent up in the same direction, and these are integrally attached by calking joining. This enables the strength of an anchor body to be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method of manufacturing a step fitting to be attached to a hole wall of a manhole, etc.

<Prior Art> Generally, a plurality of step fittings are attached to the hole walls of sewerage manholes in the vertical direction for the purpose of raising and lowering workers.

A conventional method of manufacturing this step fitting will be explained with reference to FIG.

Usually, a U-shaped bar 1 is used as a step fitting, and the U-shaped bottom of this bar 1 is formed flat, and a step 11 is provided on which the worker rests his or her feet.

Furthermore, threaded portions 5 are provided at both ends of the bar 1.

Next, regarding the anchor tube 6, this anchor tube 6 is a hollow tube with both ends open, and from the end surface of one end, a plurality of slits 6 of a predetermined length are formed in a direction horizontal to the axis of the anchor tube 6.
1 is opened, and a screw groove 62 is carved in the inner peripheral surface of the other end.

Finally, the threaded portion 5 of the bar 1 formed as described above and the threaded groove 62 of the anchor tube 6 are screwed together to complete the manufacture of the step fitting.

<Problems to be Solved by the Present Invention> The conventional step metal manufacturing method described above has the following problems.

<A> In the conventional method for manufacturing step metal fittings, the slit 61 must be cut in the anchor tube 6 using a cutting machine such as a shaping machine.

Therefore, the slit forming operation takes time and effort, which causes a decrease in work efficiency in the case of mass production.

<Opening> In order to screw together the bar 1 and the anchor tube 6, it is necessary to thread each of them, which complicates the manufacturing work.

<C> Since the bar 1 and the anchor tube 6 are connected by screws, their integrity is poor and there is a problem in strength.

<Objective of the present invention> The present invention was made to solve the above-mentioned problems, and provides a method for manufacturing a step fitting that can be manufactured easily and in a short time, and that can improve strength. The purpose is to

<Configuration of the Present Invention> An embodiment of the present invention will be described below with reference to the drawings.

<A> Step processing (Fig. 3) First, as in the conventional method, a U-shaped bar 1 made of a steel bar or the like bent into a U-shape is prepared.

Step 11 is a portion where the bottom of the U-shape of this U-shaped bar 1 is formed flat by a press or the like.

An operator can step up and down inside the manhole by placing his or her feet on this step 11.

Note that it is advisable to provide an anti-slip protrusion at this step.

<Opening> Protruding caulking portion (Fig. 1) On the end faces of both ends of the bar 1, caulking portions 2 such as cylindrical bodies having a smaller diameter and shorter length than the bar 1 are integrally formed in advance.

<C> Punching out a cross plate (Figure 3) A plate body such as a cross plate 3 having 31 groups of vane members radially is punched out using a press machine.

At the same time, a rectangular caulking hole 33 is punched in the center of the cross plate 3.

The second caulking hole 33 is of such a size that the caulking portion 2 of the aforementioned bar 1 can just be inserted therein.

In addition, a predetermined gap is left between the blade members 31 located radially, and the gap is used as the slit end surface 32.

<2> Forming of anchor cylinder (Fig. 1) The blade members 31 of the cross plate 3 punched out as described above are bent and raised in the same direction to form an anchor cylinder 34 as shown in Fig. 1.

This anchor tube 34 has a slit end surface 32 between the two blade members 31, so when it is formed into a tube shape, it becomes a cylindrical body having a slit 35 as shown in FIG. .

Further, when punching out the cross plate 3, the outer circumferential diameter of the anchor tube 34 is designed in advance to be equal to the outer circumferential diameter of the bar 1.

<E> Caulking (FIG. 2) Next, the anchor tube 34 and the bar 1 are attached together by caulking.

First, the caulking portion 2 of the bar 1 is inserted into the caulking hole 33 from a direction that does not pass through the inside of the cylindrical body of the anchor tube 34 .

Then, the bar 1 is fixed, the jig 4 is inserted into the anchor tube 34, and the caulking portion 2 is pressed to cause plastic flow in the joint, thereby caulking and joining.

This allows the anchor tube 34. ! 0: Bar t first luck is,
It will be strongly integrated.

<Method for Fixing Step Fittings> The step fittings manufactured by the manufacturing method described above are fixed to concrete 8 on the wall of a hole such as a manhole, as shown in FIG.

The wedge 7 used for fixing is, for example, shaped like a truncated cone, and the diameter of the wedge 7 on the small circular surface side is slightly smaller than the inner diameter of the anchor tube 34, and the diameter on the large circular surface side is made larger. do.

Furthermore, serration grooves 71 are formed on the circumferential surface of the wedge 7 on the small circular surface side, thereby improving the fixing properties of the step metal fittings.

An installation hole having a diameter slightly larger than the diameter of the wedge 7 or the bar 1 is previously opened in the concrete 8 at a predetermined position.

First, the small circular surface side of the wedge 7 is temporarily inserted into the anchor tubes 34 at both ends of the U-shaped bar 1.

Next, with the step 11 horizontal, both ends of the bar 1 are inserted into the installation hole of the concrete 8, and a striking force is applied with a hammer or the like.

Then, the wedge 7 is gradually press-fitted into the anchor tube 34,
The blade member 31 is in an outwardly tapered open state.

Therefore, the blade member 31 penetrates into the surrounding concrete 8, making it possible to securely fix the step fitting.

<Other Examples> As another example, the caulking hole 33 of the anchor tube 34
A case may be considered in which an annular bottom flange 36 is press-formed on the periphery of the end face in the example.

In this case, the anchor tube 34 is formed to have a slightly larger diameter than the U-shaped bar 1, and the inner diameter of the bottom flange 36 is formed to such an extent that the U-shaped bar 1 can just fit therein.

By forming the bottom flange 36 in this way, when the U-shaped bar 1 is caulked and joined later, the U-shaped bar 1
The anchor tube 34 can be more firmly joined to the anchor tube 34.

<Effects of the Present Invention> Since the present invention has been described above, the following effects can be expected.

<B> In the conventional manufacturing method of step metal fittings, slits must be cut into the anchor tube using a cutting machine such as a shaping machine, which takes time and effort, and is difficult in the case of mass production. This causes a decrease in work efficiency.

In contrast, in the present invention, the slits can be formed simply by punching out a plate such as a cross board in an instant using a press and then bending it.

Therefore, compared to conventional manufacturing methods, the step metal fittings can be manufactured easily and quickly, and work efficiency can be improved even in the case of mass production.

<mouth> Conventionally, in order to connect the rod and the anchor tube with screws,
It is necessary to thread each part, which complicates manufacturing work.

However, since the present invention uses caulking rather than screw connection, there is no need to perform thread cutting work, and workability is improved.

〈C〉Since the conventional bar and anchor tube are connected by screws,
It lacks integrity and has problems with strength.

However, in the present invention, the rod and the anchor tube can be strongly integrated by caulking.

Therefore, the strength of the anchor can be improved.

[Brief explanation of the drawing]

Figure 1: An explanatory diagram of one embodiment of the present invention. Figure 2: An explanatory diagram of the caulking connection between the bar and the anchor tube. Figure 2. A perspective view of the two-cross board. Figure 2: Explanatory diagram of other embodiments Figure 6: Explanatory diagram of prior art

Claims (1)

[Claims] (1) The U-shaped bottom of the U-shaped bar is formed flat to provide a footrest surface, and caulked parts are protruded from the end faces of both ends of the bar, and a press machine is used to radially form the U-shaped bottom at predetermined intervals. At the same time, punch out a plate having a group of blades, at the same time punch a caulking hole in the center of this plate, bend and raise the blades of this plate in the same direction to form a cylinder with a slit, and form a cylinder with a slit. A method for manufacturing a step fitting, characterized in that the caulking portion of the bar is inserted into the caulking hole of the cylinder without passing through the inside, and the step fitting is manufactured by caulking and joining.