JPH086828Y2 - Manhole foot rest - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a footrest for a manhole used for elevating a manhole.

(Prior Art) There are two manhole construction methods. The first is a method of directly placing concrete at a manhole bending site, and the second is a method of transporting and burying a hume pipe manufactured in a factory to a manhole construction site.

In more detail below regarding these, in the former case, the inner and outer double molds are concentrically arranged in the bending hole of the manhole, then concrete is placed between the inner and outer molds, and then the mold is The manhole is completed by removing it, and the footrests are installed as follows.
That is, after installing the formwork as described above, attach a nest between the inner and outer formwork before placing the concrete, then place the concrete between the inner and outer formwork, and then insert the nest at the time of removing the formwork. Remove and form an insertion hole at the tip of the step, insert the step tip into the insertion hole from the inside of the concrete wall to project it to the outer surface of the concrete wall, and fix the step by screwing a nut on this protruding end. The steps are taken.

Explaining the latter construction method next, when manufacturing a fume pipe in a factory, etc., the inner and outer molds are arranged concentrically, concrete is placed between the inner and outer molds, and then the inner and outer molds are placed. The mold is removed by pulling it out in the axial direction, but it is necessary to form a step mounting hole in the fume tube used for the manhole, and then insert a nest between the inner and outer molds as before, and then Concrete is being poured into. After transporting the fume pipe manufactured in this way to the manhole construction site and installing it in the bending hole, insert the tip of the step into the step mounting hole from the inside of the fume pipe and project it outward, and attach the nut to this protruding end. The step is fixed by screwing it in.

(Problems to be solved by the invention) In both cases of directly placing concrete at the manhole construction site and using fume pipes, the tip of the step is inserted from the inside of the concrete wall to project to the outside of the concrete wall. Since it is necessary to screw the nut into this protruding end, two workers are required, one for inserting the step inside the concrete wall and one for screwing the nut outside the concrete wall. It took time.

Further, in any of the above cases, the tip of the step is inserted into the through hole formed by removing the nest, but it is unavoidable that a gap is created between the opening inside the through hole and the tip of the step. Therefore, repair work was required to fill this gap with concrete.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a footrest for a manhole in which steps can be easily and quickly attached and no repair is required after attachment.

(Means for Solving the Problem) A footrest for a manhole according to the present invention for achieving the above object is a hollow closure body embedded in a concrete wall and having an opening opening to an inner surface of the concrete wall, An engaging portion that is insertable from the opening of the hollow closing body and is in close contact with and elastically engageable with the engaging portion formed on the inner wall of the hollow closing body, and the engaging portion of the opening and the engaging portion of the hollow closing body. A footrest for a manhole, comprising a step having a fitting portion at a tip end that is in close contact with a through hole located between the stopper and the fitting portion, and the engaging portion and the fitting portion in the step are Made of resin,
The engaging portion is formed with a ridge protruding in a direction orthogonal to the axis of the step tip, and the engaging portion and the fitting portion are compressed so as to extend along the axis of the step tip. A groove absorbing portion for absorbing force is formed.

(Operation) When mounting the step, the step may be inserted into the opening of the hollow closing body from the inside of the concrete wall. When the step is inserted, the engaging portion of the step elastically engages with the locking portion of the hollow closing body. At the same time, the fitting portion of the step fits into the through hole of the hollow closing body.

(Effect of the Invention) As described above, when mounting the step, it is sufficient to insert the step from the inside of the concrete wall into the opening of the hollow closing body, and therefore the mounting of the step can be easily and quickly performed by one operator. .

Further, since the hollow closing body is still embedded in the concrete wall, there is no gap between the hollow closing body and the concrete, and therefore repair after step mounting is unnecessary.

Further, since the engaging portion and the fitting portion of the step are made of a resin having elasticity, and these can be closely fitted or engaged with the locking portion and the through hole of the hollow closing body, the step can be performed in the hollow closing body. It can be firmly attached without backlash.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. First
In FIG. 2 and FIG. 2, reference numeral 1 is a cylindrical concrete wall installed in a manhole bending hole, and a hollow closed body 2 made of a cylindrical hollow body is embedded in the concrete wall 1. The hollow closing body 2 is composed of a metal cylindrical base body 2a and a resin covering body 2b. The open end of the cylindrical base body 2a is bent outward, and the inner and outer peripheral surfaces of the bent portion 3a and a part of the cylindrical portion 3b connected to the bent portion are covered with a tubular cover 2b. The inner peripheral wall of the cover 2b is formed with a groove portion 4 having a curved surface whose cross-sectional shape of the bottom portion is curved outward, and the inner peripheral wall between the groove portion 4 and the opening 5 has a diameter that decreases toward the groove portion 4. Is formed in the tapered through hole 6.

Reference numeral 7 denotes a mounting portion formed at the tip of step 21 used for raising and lowering the manhole. The mounting portion 7 includes a core material 7a made of a metal rod-shaped member and a core material 7a as shown in FIG. 1 (b). It is composed of a resin covering member 7b for covering all parts except the tip portion, and a ridge portion 8 which is elastically engaged with the groove portion 4 of the covering body 2b is formed at the tip portion of the covering member 7b. The cross section of the protruding portion 8 is formed as a curved surface that curves outward. The outer peripheral wall of the covering member 7b connected to the ridge portion 8 is formed into a taper fitting portion 9 whose diameter becomes smaller toward the ridge portion 8, and the taper fitting portion 9 is fitted into the taper through hole 6 of the covering body 2b. It is free. Reference numeral 10 denotes a groove-shaped absorbing portion, which is formed so as to extend along the axis of the step tip portion from the ridge portion 8 to the taper fitting portion 9.

Reference numeral 11 denotes a threaded portion formed on the inner wall of the tapered through hole 6 of the cover 2b for screwing a cover member described later. Reference numeral 12 denotes a nut member fixed to the outer surface of the bottom of the hollow closing body 2, 13 denotes a screw rod screwed to the nut member 12, and 14
Is a support member through which the screw rod 13 is inserted and is in contact with the outer surface of the concrete wall 1, 15 is a nut screwed into the screw rod 13, and 16 is an adhesive agent filled in the space of the hollow closing body 2.

Next, a procedure for installing the footrest including the hollow closing body 2 and step 21 will be described. The concrete wall 1 in this case is a fume tube. After the inner and outer molds are installed as described above, the hollow closing body 2 is installed between the inner and outer molds. In this case, the opening of the hollow closure 2 faces the inner mold. Then, as shown in FIG. 3, a plate-shaped cover member 17 made of resin and having a threaded portion formed on the outer peripheral surface thereof is screwed into the threaded portion 11 of the cover 2b.

After covering the opening of the hollow closing body 2 with the cover member 17 in this manner to seal the hollow closing body 2, concrete is poured. After placing concrete, remove the inner and outer formwork,
Further, by using the handle 17a of the cover member 17, the cover member 17
After removing, install in the bending hole for manhole. Then, from the inside of the fume tube, attach the end of step 21 to the hollow closure 2
To insert. Since the outer diameter of the protruding portion 8 is set to be larger than the inner diameter of the tapered through hole 6, the protruding portion 8 is formed in the tapered through hole 6.
It is compressed as it passes through the
Is formed, it is relatively easy to occur. Then, as step 21 is further inserted and the ridge portion 8 enters the groove portion 4, this compression is gradually released, and when the ridge portion 8 is completely in the groove portion 4, the ridge portion 8 is completely in its original shape. It returns and elastically engages with the groove portion 4.

 On the other hand, the tapered fitting portion 9 fits into the tapered through hole 6.

When the adhesive 16 is used, it is filled in the hollow closing body 2 in advance before the step 21 is inserted. By using adhesive, hollow closure 2 and step 21
The gap between and is completely sealed, and good watertightness is maintained.

Since the hollow closing body 2 receives the compressive force of the concrete when it is cast into the concrete, it does not come off from the fume pipe. The nut 15 may be screwed into the screw rod 13 via the screw.

FIG. 4 shows another embodiment of the present invention, which is different from the first embodiment in that the hollow closing body 2 is provided with a coil spring 18 made of metal. That is, as shown in FIGS. 4 and 5, a metal coil spring 18 is wound around the outer circumference of the hollow closing body 2. By providing the coil spring 18 in this manner, the attachment strength of the hollow closing body 2 to a concrete wall is increased. Can be further increased. Note that, as shown in the figure, it is possible to cover the entire outer surface of the cylindrical base 2a with the cover 2b.

FIGS. 6 and 7 show a third embodiment of the present invention. In this embodiment, the outer peripheral surface of the covering 2b is formed with a sharp-edged tip and the circumferential direction or diameter of the concrete wall 1 is set. A protrusion 19 extending inward is formed. Further covered
The bottom cross section of the groove 20 of 2b is formed into an acute angle, and the covering member 7b
The cross section of the protrusion 8 is also formed in an acute angle.

 FIG. 8 shows a representative example of steps.

[Brief description of drawings]

 1 (a) is a cross-sectional view of a footrest according to the present invention, FIG. 1 (b) is a cross-sectional view taken along the line AA of FIG. 1 (a), and FIG. 2 (a) is a hollow closure. A plan view of the body, FIG. 2 (b) is a side view of the hollow closing body, FIG. 3 (a) is a cross-sectional view showing a mounted state of the cover body, and FIG. 3 (b) is a view of FIG. 3 (a). Bottom view, FIG. 4 is a sectional view of the second embodiment of the present invention, FIG. 5 (a) is a plan view of the hollow closing body of FIG. 4, and FIG. 5 (b) is a hollow closing body of FIG. FIG. 6 is a sectional view showing a third embodiment of the present invention, FIG. 7 is a side view of the hollow closing member shown in FIG. 6, and FIG. 8 is a plan view showing a mounting state of steps. 1 ... Concrete wall 2 ... Hollow closure 4,20 ... Groove (locking part) 5 ... Opening 6 ... Taper through hole 8 ... Ridge (engagement) 21 ... Step

Claims (1)

[Scope of utility model registration request] 1. A hollow closing body which is embedded in a concrete wall and has an opening opening to an inner surface of the concrete wall, and which is insertable from the opening of the hollow closing body and formed in the inner wall of the hollow closing body. An engaging portion that is in close contact with the engaging portion and is elastically engageable, and a fitting portion that is in close contact with and can be fitted into the through hole located between the opening portion of the hollow closing body and the engaging portion are provided at the tip portion. A foothold for a manhole comprising a step having, wherein the engaging portion and the fitting portion of the step are made of resin, and the engaging portion has a ridge protruding in a direction orthogonal to the axis of the step tip portion. A portion is formed, and extends along the axis of the step tip portion to the engaging portion and the fitting portion,
A footrest for a manhole, wherein a groove absorbing portion for absorbing a compressive force is formed.