JP3819992B2 - Manhole footrest device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a manhole footrest device.
[0002]
[Prior art]
As this type of conventional one, for example, there is one disclosed in JP-A-7-42183. That is, a screw part is formed at both ends of the U-shaped step, and the resin is continuously covered from the main body part of the step to the middle of the left and right bent parts, and the ridges are respectively placed in the middle of the bent parts. Formed integrally with the coating, the bent part is inserted into the step insertion hole of the concrete cylinder, the both sides are brought into close contact with the inner surface of the concrete cylinder, and a nut is screwed onto the screw part to attach the step to the concrete cylinder. To fix. Here, each of the above ridges is formed into a ridge shape that is concave toward the inside of the concrete cylinder, and the coating resin that forms the ridge is made of a material that elastically deforms when pressurized. Therefore, since the flange is elastically deformed and its peripheral edge is brought into close contact with the inner surface of the concrete cylinder, the step can be attached while keeping the water tightness with the flange regardless of the curvature of the inner surface of the concrete cylinder within a certain range. .
[0003]
[Problems to be solved by the invention]
However, in such a prior art, it adheres to the inner surface of a concrete cylinder only by the elastic deformation of the said collar. Therefore, it could be applied only within a certain range of the inner surface curvature of the concrete cylinder. In addition, since the resin is integrally formed with the resin coating of the step main body, the selection range of the resin that satisfies both the properties of the resin required for the step main body and the bag is very limited. That is, the step body resin is preferably hard, and the heel resin is desired to be soft and rich in elastic deformation, and the conflicting requirements must be satisfied. In addition, the nut must be tightened while deforming the heel, requiring considerable effort from the operator.
[0004]
An object of the present invention is to solve the above-mentioned problems and to provide a manhole footrest device that enables attachment of a step regardless of the inner curvature of the manhole of a concrete cylinder.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, the configuration of the present invention is as follows. That is, in the first configuration, screw portions are formed at both ends of the U-shaped step, and resin coating is continuously applied from the both ends of the main portion of the step to the middle of the bent leg portion. In a manhole footing device that is inserted into a step mounting hole of a body, a nut is screwed onto the screw part, and the step is fixed to a concrete cylinder, a spherical convex part is formed in the middle of the leg part of the step. This is because the part is integrally formed concentrically with the central axis of the leg part, and a separate flange member is fitted to the spherical convex part so as to be slidable.
[0006]
In the second configuration, in addition to the first configuration, the flange member has an overall shape of a truncated cone, and has a spherical inner surface that can slide on the spherical convex portion of the step at the small-diameter end portion. The diameter end side is made thin so as to be easily elastically deformed.
[0007]
In the third configuration, in addition to the first configuration or the second configuration, an annular packing is interposed near the large-diameter end of the flange member.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below based on an embodiment shown in the drawings. 1 and 2, screw portions 1c are formed at both ends of a U-shaped step 1 steel core rod 1f, and the core rod 1f extends from the main portion 1a of the step to the middle of the leg portion 1b bent left and right. The synthetic resin coating 1e is continuously applied to the outer periphery. The legs 1b are inserted in step mounting hole A ₀ of the concrete cylinder A, the nut 7 is screwed on the screw portion 1c, the step 1 is fixed to the concrete cylinder A.
[0009]
Here, in the middle of the leg portion 1b of the step, a spherical convex portion 1d made of synthetic resin is integrally formed with the covering 1e concentrically with the central axis of the leg portion. A flange member 2 made of a separate synthetic resin is fitted to the spherical protrusion 1d so as to be slidable. The scissors member 2 has a main body 21 that has an overall shape of a truncated conical cylinder, and has a spherical inner surface 21a that can be slidably rotated by the spherical convex portion 1d at a small-diameter end portion. In this order, a tapered inner surface 21b, an annular flat surface 21c, and an annular flat end surface 21d are formed. And the annular packing 22 is adhere | attached on the annular plane 21c.
[0010]
In the concrete cylindrical body A, an attachment hole A ₀ composed of a cylindrical large-diameter portion A ₁ and a tapered tapered small-diameter portion A ₂ passes through concentrically in order from the outer peripheral surface to the inner peripheral surface. It penetrates in parallel. Then, the inside of the concrete cylinder A, the step 1 is its legs 1b by penetrating the mounting hole A _0, is interposed a first packing 3 cylindrical in the intermediate-diameter portion A _2, and the washer 6 the The 2 packing 4 is interposed in the large diameter portion, and then the nut 7 is screwed into the screw portion 1c and tightened.
[0011]
As a result, step 1 is drawn into the mounting hole A ₀ of the concrete cylinder A up to the base of the spherical convex portion 1d. At the same time, the eaves member 2 takes a posture along the inner surface of the concrete cylindrical body A by the sliding rotation between the spherical inner surface 21a and the outer surface of the spherical convex portion 1d of Step 1, and elastically deforms, The annular packing 22 is in close contact with the inner surface of the concrete cylindrical body A together with the large-diameter annular flat end surface 21d. As a result, a sealing action against rainwater occurs, and the length of protrusion of the step 1 from the cylindrical inner surface is regulated. The washer 6 is positioned at the step A ₃ at the boundary between the large diameter portion A ₁ and the small diameter portion A ₂ of the mounting hole A ₀ while pressing the first and second packings 3 and 4. Thereafter, the mortar 5 is filled into the large diameter portion A ₁ . Since the small-diameter portion A ₂ of the mounting hole is a tapered hole, the pressing force on the tapered surface is generated by the pressing of the first packing 3, and the sealing effect is extremely good.
[0012]
The small diameter hole A ₂ may be a tapered hole having a large diameter toward the inside of the concrete cylinder. In addition to the cylinder, the concrete cylinder may be a rectangular cylinder or other shapes. The first and second packings 3 and 4 may be integrated.
[0013]
The present invention is not limited to the above-described embodiments and embodiments, but includes various modifications without departing from the spirit and scope of the claims.
[0014]
【The invention's effect】
According to the configuration of the present invention, the eaves member and the step main body are separated from each other, so that the eaves member moves along the spherical portion of the main body corresponding to the curvature of the inner surface of the concrete cylinder and adheres to the inner surface, so that the sealing effect is good. Further, the resin coating of the step body and the material of the eaves member need not be the same, and can be freely selected. Moreover, since the eaves member can move freely along the inner surface of the concrete cylinder, the labor of tightening the nut on the screw portion of the step body can be greatly reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of the present invention.
FIG. 2 is an enlarged partial cross-sectional view of a flange member.
[Explanation of symbols]
1 Step 1a Main part 1b Leg part 1c Screw part 1d Spherical convex part 1e Cover 1f Core material 2 Collar member 21 Main body 21a Spherical inner face 21b Tapered inner face 21c Annular flat face 21d Annular flat end face 22 Packing 3 First packing 4 Second packing 5 Mortar 6 Washer 7 Nut A Concrete cylinder A ₀ Mounting hole A ₁ Large diameter hole A ₂ Small diameter hole A ₃ Step

Claims (3)

Screw parts are formed at both ends of the U-shaped step, and resin coating is continuously applied to the middle of the leg part bent from both ends of the main part of the step, and the leg part is inserted into the step mounting hole of the concrete cylinder. In the manhole footing device in which a nut is screwed onto the screw part and the step is fixed to a concrete cylinder,
In the middle of the leg portion of the step, a spherical convex portion is integrally formed concentrically with the central axis of the leg portion, and a separate flange member is fitted to the spherical convex portion so as to be slidable. A manhole footrest device. The scissors member generally exhibits a truncated conical cylinder shape, and has a spherical inner surface that can be slidably rotated on the spherical convex portion of the step at the small diameter end portion, so that the large diameter end side is easily elastically deformed, 2. The manhole footrest device according to claim 1, wherein the thickness is reduced. 3. The manhole footrest device according to claim 1, wherein an annular packing is interposed in the vicinity of the large-diameter end of the flange member.

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