JPS643910Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention is used for underground power distribution to be inserted into the unwired empty pipe end of underground cable protection pipes buried for power supply to buildings, etc. This invention relates to a waterproof plug at the mouth of a cable protection pipe.

BACKGROUND OF THE INVENTION In recent years, in urban areas, cables for power supply are often buried underground. In order to bring the underground cable into the building, as shown in Figure 5, the empty pipe C of the cable protection pipe, which has been laid underground B in Building A under construction, is passed through the underground side wall D of Building A. Underground cables are laid out in such a way that they can be easily drawn into buildings, but there is a risk of groundwater entering the building through the protection pipes installed in the building's basement before the cables are routed. A waterproof plug E is installed at the end of the tube to prevent
is installed.

As shown in FIG. 4, this waterproof plug E obtains a waterproof effect by driving a wooden plug E made of wood such as cypress into a conical shape into the end of the empty pipe C of the cable protection pipe.

Problems to be solved by the invention: The above waterproof plug cannot be removed from the pipe end in order to lay a cable without destroying the wooden plug E, so it cannot be reused.
In addition, there is a risk of damaging the cable protection pipe C, and the plug may loosen or fall off due to vibrations from the ground. Furthermore, since it is made of wood, there are problems such as corrosion, and a reliable waterproofing effect cannot be obtained.

Means for Solving the Problems The purpose of this invention is to obtain a waterproof plug that can be easily attached to and removed from the end of a cable protection pipe and has a complete waterproof effect. A seal rubber body is formed of a drum-shaped cylindrical body with a bulged center part, and a plurality of annular protrusions are provided on the outer peripheral surface of the bulge center part of the seal rubber body, and a plurality of annular protrusions are formed between the annular protrusions. An underground power distribution cable protection pipe in which an annular groove is filled with a water-swellable material, and tightening fittings are provided on both sides of the seal rubber body, and the seal rubber body is formed so as to be tightenable with bolts and nuts. This was done as a waterproof plug at the pipe entrance.

Function: Insert the waterproof plug into the port of the cable protection pipe so that the nut is located on the outside of the pipe, and then tighten the bolt (nut) in this state.The seal rubber body will be crushed by the tightening fitting and the width will be Although it is smaller, the outer diameter direction is larger, and the annular protrusion sticks closely to the inner circumferential wall of the protective tube to prevent water intrusion.If water intrudes to some extent, the water-swellable material swells and prevents water intrusion. , a reliable water-stopping effect can be obtained.

Embodiment An embodiment of the waterproof plug of this invention will be explained with reference to a drawing. It is made of a special rubber consisting mainly of natural rubber and butadiene rubber, and has a so-called drum shape with a gentle slope from the center to both ends. A seal rubber body 3 is formed of a cylindrical body, and a plurality of annular protrusions 4 and annular grooves 5 are alternately provided on the outer peripheral surface of the central part of the drum-shaped body.

Further, the annular groove 5 is filled with a water-swellable material 6, which is a rubber adhesive mixed with water-swellable resin powder. Further, a fastening fitting 1 formed by welding one end of a bolt 2 to a metal disc is attached to one side of the seal rubber body 3, and the attachment is done by passing the bolt 2 through the seal rubber body 3. The metal disk-shaped tightening fitting 7 is inserted and attached to the bolt 2 protruding from the other side of the seal rubber body 3, so that it overlaps with the other side of the seal rubber body 3, and a nut 8 is provided on the bolt 2, and the nut 8 is tightened. Clamp the seal rubber body 3 with fittings 1 and 7,
It is formed in a structure that is tightened by a melt 2 and a nut 8.

This waterproof plug is as described above, so when the product of the present invention is inserted into the end of the protective tube 9 with the nut 8 facing toward you and the nut 8 is tightened, the fasteners 1 and 2 are brought close together. Drop.

Therefore, the seal rubber 3 is compressed in the axial direction and expands in the radial direction, and the plurality of annular protrusions 4 are attached to the protective tube 9.
Closely adheres to the inner wall of the building to prevent infiltration from the outside. Even if some water enters, the water-swellable material 6 expands and prevents further water entry, achieving a complete water-stopping effect.

On the other hand, the nut 8 is rotated in the opposite direction to take out the product of the present invention from the protective tube 9.

Effects Since the present invention has the above-mentioned configuration, it can be easily inserted into the end of the tube, and by tightening the nut 8, the seal rubber easily expands in the radial direction.In particular, since the center is drum-shaped, it can easily be inserted into the end of the tube. In addition, the plurality of annular protrusions 4 prevent water from entering, and the water-swellable material 6 prevents water from entering. Furthermore, by returning the nut 8, the product of the present invention can be easily removed from the tube end, which has the effect of improving workability.

Further, the waterproof plug of this invention can be easily removed by operating the nut 8, so it can be removed without damaging the protective tube, and it can be reused, which is convenient.

[Brief explanation of drawings]

The figures show an embodiment of this invention, in which Fig. 1 is a partially sectional front view of a waterproof plug, Fig. 2 is a sectional view taken along the line - in Fig. 1, and Fig. 3 is a sectional view showing the state of use. FIG. 4 is a perspective view of a conventional waterproof plug, and FIG. 5 is a diagram showing the conventional state of use. DESCRIPTION OF SYMBOLS 1... Tightening metal fitting, 2... Bolt, 3... Seal rubber body, 4... Annular protrusion, 5... Annular groove, 6...
...Water-swellable material, 7...Tightening fitting, 8...Nut.

Claims (1)

[Scope of utility model registration request] A plurality of annular protrusions 4 are provided on the outer peripheral surface of the center of the seal rubber body 3 formed in the shape of a drum, and annular grooves 5 formed between the annular protrusions 4 are each filled with a water swelling material 6. , an underground power distribution cable protection pipe characterized in that tightening fittings 1 and 7 are provided on both sides of a seal rubber body 3, and the seal rubber body 3 is formed so as to be tightenable with bolts 2 and nuts. Waterproof plug at the mouth.