JPS6125311Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a waterproof plug that closes a conduit opening to prevent water from flowing into a cable conduit.

[Conventional technology]

The pipe entrance of underground cable conduits opens inside the manhole, so rainwater that has entered the cables flows into empty pipes where no cables are drawn, and when new cables are drawn into the pipes. For this reason, the pipe entrances of empty pipes were closed off with waterproof plugs.

[Problem that the invention attempts to solve]

As mentioned above, even if a waterproof plug is attached to an empty pipe entrance, after a long period of time, water such as groundwater will remain in the empty cable pipe, and when this accumulated water becomes large, the water pressure will cause it to be attached to the pipe entrance. In some cases, the waterproof plug that was installed was pushed out and fell off.

For this reason, the present applicant proposed a waterproof plug in Japanese Utility Model Application No. 115595/1983 which was designed to prevent it from falling out of the pipe opening even when subjected to water pressure. There was a problem in that if the waterproof plug was pulled out when a new cable was being brought in, a large amount of water inside the pipe would gush out from the pipe opening, which would hinder the work.

Furthermore, the proposed waterproof plug has a problem in that it is difficult to pull out the waterproof plug inserted into the pipe opening when the pressure inside the pipe is lower than the outside pressure inside the main hole.

Therefore, the present invention has been developed to prevent water from suddenly gushing out when the waterproof plug is pulled out from the pipe opening, even if a large amount of water remains in the cable pipe, and to prevent water from suddenly gushing out when the water plug is pulled out from the pipe opening, and to prevent water from suddenly gushing out when the water plug is pulled out from the pipe opening. To provide a waterproof plug that can eliminate a reduced pressure state.

[Means for solving problems]

In order to solve the above-mentioned problems, the waterproof plug of the present invention has a core tube into which both fixed and movable disks having an annular inclined plate part and a rubber disk packing sandwiched between the two disks are inserted. This heart tube is especially equipped with drainage and
A hollow core tube with a structure having a hollow passage for ventilation, a cylindrical nut screwed into the threaded part on the outer circumferential surface of the hollow core tube, and a cap nut, in particular, screwed into the tip of the hollow core tube. It is.

[Function] The cap nut screwed onto the tip of the hollow core tube watertightly closes the opening at the tip of the hollow core tube.

When removing this waterproof plug, leave it attached to the cable conduit entrance and remove the cap nut screwed onto the tip of the hollow core tube, and the water remaining in the conduit will flow out from the tip of the hollow core tube. Therefore, it becomes possible to receive this water in a container or the like, and there is no possibility that a large amount of water suddenly spews out the moment it is pulled out from the pipe opening, unlike the waterproof plug disclosed in the above-mentioned patent application.

In addition, even if the inside of the cable conduit is under reduced pressure, if you remove the cap nut screwed onto the tip of the hollow core tube, the inside of the conduit will communicate with the outside air of the mahole and the depressurized state will be resolved, making it easy to remove the waterproof plug. becomes possible.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of the waterproof plug of the present invention, and FIG. 2 is a side view showing the upper half in cross section.

First, the waterproof plug of the present invention has, as its main components, a metal hollow core tube 1 having a hollow channel 12 for drainage and ventilation, and a metal fixing disk 2 fixed to the rear end of the hollow core tube. , a metal movable disk 3 that is movably fitted, a rubber disk packing 4 that is installed between the fixed disk and the movable disk, a metal stopper plate 5, and screwed onto the outer periphery of the hollow core tube. The hollow core tube is provided with a cylindrical nut 7 and a cap nut 8 which is screwed onto the tip of the hollow core tube and closes the opening at the tip. Each of the above-mentioned constituent members will be explained in detail below.

:Construction of hollow core tube 1: The hollow core tube 1 has a threaded portion 11 for screwing together a cylindrical nut and a cap nut on the outer circumferential surface of the front portion excluding the rear end of the hollow core tube. Also, this hollow core tube 1
A hollow passage 12 for drainage and ventilation is formed by a hollow passage passing through the inside to drain water in the cable conduit and to communicate the inside of the cable conduit with outside air.

: Structure of the fixed disk 2 and the movable disk 3: The fixed disk 2 has an annular inclined plate part 21, an annular peripheral plate 22 on the outer periphery thereof, and a central hole 23. The rear end of the air core tube 1 is fitted and fixed by welding.

The movable disc 3 is constructed symmetrically with the fixed disc 2, and has an annular inclined plate part 31, an annular peripheral part 32 on the outer periphery, and a central hole 33.
is fitted into the hollow core tube 1 so as to be movable in the axial direction so as to face the fixed disk 2.

:Construction of the rubber disc packing 4: The rubber disc packing 4 consists of two annular parts 41 and 42 each having a circular or elliptical cross section, which are joined together in a double annular shape at a joining part 43. The diameter of the ring is set to a diameter that faces the annular inclined plate portions 21 and 31 of the fixed disk 2 and movable disk 3. A membrane plate 44 is integrally provided within the ring of one of the two circular ring parts 41, and a membrane plate 44 with a diameter slightly smaller than the diameter of the rear end of the hollow core tube 1 is provided at the center of the membrane plate 44. A central hole 45 is provided.

This central hole 45 is inserted into the rear end of the hollow core tube 1, and the inner peripheral edge of the hole is brought into close contact with the peripheral surface of the rear end of the hollow core tube. The fixed disc 2 and the movable disc 3 are sandwiched and mounted between the opposing annular inclined plate parts 21 and 31.

:Construction of the stop plate 5: The stop plate 5 prevents the waterproof plug from entering too deeply into the pipe opening, and has stop pieces 51 at both ends of the long and narrow plate, and a hole 52 in the center. The hollow core tube 1 is inserted into the central hole 52 and the movable disk 3
attached adjacent to the outer surface of the Note that a washer 6 is interposed between the stop plate 5 and the movable disk 3.

:Construction of the cylindrical nut 7: The cylindrical nut 7 has a screw provided on the inner surface of the cylindrical body to be screwed into the threaded portion 11 on the outer circumferential surface of the hollow core tube 1. Attach by screwing together and pushing the movable disc 3 and metal 6.

: Structure of the cap nut 8: The cap nut 8 has a screw on its inner surface for screwing into the threaded part 11 on the outer peripheral surface of the tip of the hollow core tube 1, and a packing 9 and a washer 10 are installed on the inner bottom of the cap nut. It is screwed onto the distal end of the hollow core tube 1 to close the opening at the distal end of the hollow core tube.

: Installation of waterproof plug and explanation of usage conditions: Hollow core tube 1, fixed disk 2, movable disk 3,
A waterproof plug constructed of a rubber disc packing 4, a stop plate 5, a cylindrical nut 7, and a cap nut 8 is as shown in the figure. To install this at the cable conduit entrance, hold the cylindrical nut 7 part with your hand at the conduit entrance A where the empty conduit with no cables is opened in the manhole, and hold the fixing disk 2, If you insert the movable disc 3 and the rubber disc packing 4 sandwiched between them and screw the cylindrical nut 7, the end of the cylindrical nut 7 will move the movable disc 3 to the fixed disc 2.
The annular portion 41 of the rubber disk packing 4 is pressed toward the fixed disk 2 and the movable disk 3, and is sandwiched between the opposing annular inclined plate portions 21 and 31 of the movable disk 3.
42 is compressed by both inclined plate portions and pushed outward, so that the outer circumferential surfaces of the annular portions 41 and 42 are strongly pressed against the inner circumferential surface of the conduit port A, and are fixed in pressure contact.

In this way, the cable conduit opening is watertightly closed by the rubber disc packing 4 of the waterproof plug and the cap nut 8, so even if rainwater enters the manhole, it will be prevented from entering the cable conduit. Become. Since the annular parts 41 and 42 of the rubber disc packing 4 are strongly pressed against the inner circumferential surface of the pipe port, and the stop plate 5 is in contact with the front surface of the pipe port A, a large amount of water remains in the pipe. Even when subjected to water pressure of

When a new cable is introduced and installed in an empty cable conduit whose waterproof plug is attached to the conduit opening as described above, first, the cap nut 8 screwed onto the tip of the hollow core tube 1 is removed. If a large amount of water remains in the pipe, when the cap nut 8 is removed, water will leak from the opening at the tip of the hollow core tube through the drainage/ventilation hollow channel 12 of the hollow core tube 1. Therefore, the water can be drained safely by immediately applying a water container, hose, etc. to this opening at the end.

After the accumulated water in the pipe is drained in this way, the cylindrical nut 7 is loosened to fix the movable discs 2 and 3.
Annular parts 41 and 42 of the rubber disc packing 4 according to
When the pressure is released, the pressure contact between the outer circumferential surface of the annular part and the inner circumferential surface of the pipe port is released, and the waterproof plug can be removed safely and easily without a large amount of accumulated water gushing out from the pipe port. Become. If water does not come out from the opening at the tip of the hollow core tube 1 even after removing the cap nut 8 as described above, it means that there is no accumulated water in the cable conduit, so immediately loosen the cylindrical nut 7. The waterproof plug will need to be removed.

In addition, if the pressure inside the cable conduit is lower than the outside pressure inside the mahole, removing the cap nut 8 at the tip of the hollow core tube 1 as described above will allow drainage and ventilation of the hollow core tube. Since the inside of the pipe and the outside air are communicated through the hollow passage 12 and the reduced pressure state is eliminated, the waterproof plug can be easily removed.

[Effect of idea]

As mentioned above, the waterproof plug of the present invention has a hollow core tube 1 having a structure having a hollow passage 12 for drainage and ventilation, and a cap nut 8 at its tip opening.
When removing the waterproof plug from the cable conduit entrance, the cap nut 8 screwed onto the tip of the hollow core tube 1 is first removed, so even if there is a large amount of water stagnant in the conduit. Drainage can be done safely, and there is no need to worry about the sudden gushing of water that hinders work.

Furthermore, even if the inside of the pipe is in a reduced pressure state, the reduced pressure state can be resolved by removing the cap nut 8 at the tip of the hollow core tube 1 and communicating it with the outside air, making it easier to handle the waterproof plug inside the mainhole. It becomes easier.

In addition, to attach the waterproof plug to the pipe port, all you have to do is hold the cylindrical nut 7 in your hand, insert it into the pipe port, and screw this cylindrical nut 7, so the handling work is extremely easy. Since the outer circumferential surfaces of the annular parts 41 and 42 of No. 4 are strongly pressed and fixed against the inner circumferential surface of the conduit opening, even if rainwater flows into the mahole, it is not only possible to completely prevent it from entering the conduit. The waterproof plug installed in this manner has no fear of coming off from the pipe opening even if it is subjected to the water pressure of a large amount of water stagnant in the pipe or other external force. Furthermore, stop plate 5
Since it is in contact with the front surface of the conduit port A, the waterproof plug is not pushed too far into the conduit port.

[Brief explanation of the drawing]

FIG. 1 is a front view of the waterproof plug of the present invention, and FIG. 2 is a side view showing the upper half thereof in cross section. 1: Hollow heart tube. 11: Thread part. 12: Hollow passage for drainage and ventilation. 2: Fixed disc. 21: Annular inclined plate portion. 22: Annular peripheral plate. 23: Central hole. 3: Movable disc. 31: Annular inclined plate part. 32: Annular peripheral plate.
33: Central hole. 4: Rubber disc packing. 41,
42: Annular part. 43: Joint. 44: Membrane plate. 4
5: Central hole. 5: Stopping plate. 51: Stop piece part. 52:
Central hole. 6: Washer. 7: Cylindrical nut. 8: Bag nut. 9: Patsukin. 10: Washer.

Claims (1)

[Scope of utility model registration request] A fixed disk having a ring-shaped inclined plate portion is fixed to a hollow core tube having a hollow channel for drainage and ventilation, and a movable disk having a ring-shaped inclined plate portion symmetrical to the fixed disk is inserted into the hollow core tube. , a rubber disk packing is installed between the fixed disk and the movable disk, which is formed integrally with two annular portions having diameters opposite to the annular inclined plate portion and a membrane plate in the annular portion; A cylindrical nut is screwed into the threaded part provided on the outer circumferential surface of the hollow core tube, and a cap nut with a packing inserted into the inner bottom is screwed onto the tip of the hollow core tube, and the fixed disk and the movable disk are connected. A drain-type waterproof plug for a cable conduit opening, in which each inclined plate portion presses an annular portion of the panel seal.