JP2549292Y2 - Retention structure of conduit mouth waterproofing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application field] The present invention relates to an anchoring structure for preventing a cable conduit opening waterproof device from falling out of a conduit.

[Prior art and its problems] Generally, a cable port waterproofing device is attached to a cable port to prevent water from flowing out of the pipe into a manhole. For example, a conduit opening waterproofing device for a single-core CV cable is used in which a gap between a conduit and a cable is filled with a waterproof mixture, and rubber packing and a holding plate are arranged before and after each, and tightened with bolts or the like. ing.

Water may enter the pipeline for some reason,
In this case, it is conceivable that a water pressure as high as several atmospheres is generated in the pipeline. Further, the cable may extend in the axial direction due to thermal deformation of the cable itself. Each of these phenomena acts as a force for pushing out the conduit opening waterproofing device from the conduit opening, so that the waterproofing device is provided with a retaining means.

As conventional retaining means, there are means for driving an anchor bolt into a peripheral wall of a conduit opening and retaining the conduit opening waterproofing device with steel or the like fixed and supported by the anchor bolt, or a specially shaped conduit opening when the conduit is buried. For example, there is a method of forming a flange portion at a pipe opening and retaining the waterproof device at the flange portion. However, the former may break the wall when driving the anchor bolt,
In addition, the wall around the pipe entrance is covered with mortar and has no reinforcing steel, so the anchor effect cannot be expected so much, and a strong yielding force cannot be obtained. The latter has a problem that the workability is deteriorated and the cost is increased because it is necessary to have a special conduit opening shape.

By the way, in order to support a cable extension from a pipe to a manhole, a cable guide pipe (usually referred to as a trumpet pipe) is often arranged immediately before a pipe opening. The cable guide tube is fixedly supported by a supporting member firmly fixed to the pipe entrance wall surface (a concrete wall with a reinforcing bar surrounding the mortar-filled conduit entrance peripheral wall) so as to withstand the cable weight.

The present invention provides a structure for preventing a waterproofing device from being pulled out of a conduit by using a cable guide tube arranged and fixed immediately before the conduit opening so that the above-described problem does not occur. is there.

[Means for Solving the Problem] The retaining structure of the conduit opening waterproofing device according to the present invention includes a cable conduit having a cable guide tube arranged and fixed immediately before the cable conduit opening. A waterway waterproofing device is attached, and one end side is fixed to the cable guide tube, and the other end side of a fixture different from the cable guide tube supports the waterway waterproof device. is there.

[Operation] The present invention is configured such that the conduit opening waterproof device is retained by a fixture extending from the cable guide tube arranged and fixed immediately before the conduit opening. The cable guide tube is firmly arranged and fixed by its support member so that rattling and displacement do not occur.By using this cable guide tube to support the conduit opening waterproof device, a strong retaining force is provided. Obtainable.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing a side cross section of the retaining structure of the conduit opening waterproof device according to the present invention, and FIG. 2 is a diagram showing an upper cross section. In the figure, reference numeral 1 denotes a cable conduit, and its conduit opening
10 is enlarged. A cable W such as a single-core CV cable is inserted into the cable conduit 1, a conduit opening waterproof device 2 is provided at the conduit opening 10, and immediately before the conduit opening 10 (at a predetermined interval). The cable guide tube 3 supported by the support member 4 is arranged and fixed.

The conduit opening waterproofing device 2 includes a waterproof compound 21 filled in a gap between the cable W and the conduit opening 10, and a waterproof compound 21.
Ring-shaped rubber packing 22, 22 arranged on both sides of 21
And outermost ring-shaped pressing plates 23, 23, which are tightened and fixed by a plurality of bolts 24 and nuts 25 penetrating therethrough. Here, when the nut 25 is tightened more strongly, a pressure is generated in the waterproofing compound 21 by the compressive force of the rubber packings 22 and 22, and this pressure can improve the retention force of the conduit opening waterproofing device 2; If the tightening is excessively strong, an excessive surface pressure may be applied to the cable W and the cable W may be damaged. Further, in the present invention, since the fastening force of the bolt 24 and the nut 25 is not used to obtain the retention force of the conduit opening waterproofing device 2, a tightening force sufficient to secure the watertightness of the conduit opening 10 is sufficient.

The cable guide tube 3 is a tubular body in which a split member is fixed at the flange portion 30 with bolts and nuts 31, and is a tapered tube having one open end having a large diameter. The cable guide tube 3 is disposed coaxially with the conduit 1 such that a small diameter portion thereof faces the conduit opening 10. A cable W is inserted through the pipe, and the inner surface of the pipe end is formed to have a curved surface that expands outward so as not to damage the cable W. The cable guide tube 3 is integrally formed with a support portion 32 having a horizontal portion on the lower surface with respect to the tapered outer surface of the main body. The support portion 32 is supported by an angled horizontal member 41 at the support portion 32, and is supported by bolts and nuts 33. Fixed. Although not shown, the horizontal member 41 supports and fixes a plurality of cable guide tubes 3 (actually, another cable guide tube 3 exists on the upper side of FIG. 2). Horizontal material 41 is angle material 42
Are fixed by bolts and nuts 411, and are further fixed and supported by angled vertical members 43 by bolts and nuts 421. Since the pipes 1 are usually provided in a plurality of rows and a plurality of stages, the vertical members 43 are omitted in FIG. 1, but actually extend in the vertical direction and support a plurality of horizontal members 41. ing. The vertical member 43 is fixed to the pipe entrance wall T by an anchor bolt 431. The conduit 1 is converged in a mortar-filled rectangular space, usually called "borderline",
Outside the rectangular space is a concrete wall with a reinforcing bar, but the anchor bolt 431 is driven into the concrete wall with a reinforcing bar to obtain a strong fixing force. In this way, the cable guide tube 3 is composed of a horizontal member 41, an angle member 42, a vertical member.
It is firmly supported and fixed by a support member 4 including 43 and anchor bolts 431.

Extending from the cable guide tube 3 to the fixture 5,
The conduit port waterproofing device 2 is supported by the fixture 5. The fixing device 5 in the present embodiment includes a fixing metal member 51, a fixing bolt 53, and a tightening nut 52 having a U-shaped overall shape. The fixing bracket 51 has a U-shaped inner width substantially matching the lateral width of the flange member 30 of the cable guide tube 3, and is fixed to the flange portion 30 by bolts and nuts 31 at both edges 511, 511. It is integrated with the guide tube 3. A hole is provided in an intermediate portion of the fixing bracket 51, and a fixing bolt 53 is inserted into the hole,
A fixing bolt 53 is screwed and fixed by a tightening nut 52. One end of the fixing bolt 53 is a holding plate of the conduit opening waterproofing device 2.
23 and supports the conduit opening waterproof device 2.

According to the fixing device 5 having such a configuration, it is possible to easily attach the cable guide tube 3 by using the flange portion 30, and the distance between the cable guide tube 3 and the conduit opening 10 is set in each conduit 1. Even if they are different, there is an advantage that adjustment can be made very easily by adjusting the tightening position of the fixing bolt 52 by the tightening nut 52.

As shown in the upper sectional view of FIG. 2, the fixture 5 extends from each flange portion 30 of the split cable guide tube 3 and is fixed by two fixing bolts 53 located substantially diagonally. The pipe mouth waterproofing device 2 is supported. As in the present embodiment, the pipe mouth waterproofing device 2 can be stably retained by having at least two points of support. However, the number of the fixing bolts 53 is increased by forming the fixing bracket 51 in an appropriate shape, and the three-point supporting or If the support is higher than the point, it can be more stably and favorably retained. In addition, since strong de-output may act on the conduit opening waterproof device 2 due to the water pressure in the conduit 1, etc.
It is desirable to use a material having sufficiently high strength so that the fixing tool 5 is not easily deformed by the output, and for example, iron or stainless steel can be used. In addition, since eddy current is expected to be generated when the current capacity of the cable W is large, it is preferable to use a non-magnetic material as a component of the fixture 5 in this case.

The configuration of the fixing tool 5 is not limited to that of the present embodiment, but may be a simple one such as the cable guide tube 3.
The other end of an iron bar or the like having one end fixed to the flange portion 30 may directly abut on the conduit opening waterproofing device 2.
Also, without extending the fixing bracket 51 from the flange portion 30,
It is a matter of course that a threaded hole or the like is separately provided in the cable guide tube 3 and the fixing bracket 51 is extended using the hole. As an example of this case, for example, a turn-buckle-type fixing tool for providing a threaded hole at the end of the cable guide tube on the conduit opening side and pressing the conduit opening waterproofing device using a turnbuckle and two threaded rods Can be used.

[Effects] As described above, according to the retaining structure of the conduit opening waterproof device of the present invention, since the fixture is extended from the cable guide tube to retain the conduit opening waterproof device, the anchor is attached to the wall around the conduit opening. Compared to the case where a bolt is used or a special conduit port is employed, the conduit port waterproofing device can be extremely easily and inexpensively retained using the existing cable guide pipe in the manhole.

Also, since the cable guide tube is firmly installed and fixed just before the pipeline opening, a strong holding force can be obtained by extending and fixing the fixture from the guide tube, and the hydraulic pressure in the pipeline can be increased. The present invention has excellent practical effects, such as being able to oppose a strong pulling force of the conduit opening waterproofing device due to the extension of the cable.

[Brief description of the drawings]

1 and 2 are views showing the retaining structure of the conduit opening waterproofing device according to the present invention. FIG. 1 is a side sectional view thereof, and FIG.
The figures each show a sectional view from above. DESCRIPTION OF SYMBOLS 1 ... conduit, 10 ... conduit opening, 2 ... conduit opening waterproofing device, 3 ... cable guide tube, 30 ... flange part, 4 ... support member, 431 ...
Anchor bolts, 5: Fixing tool, 51: Fixing bracket, 52: Tightening nut, 53: Fixing bolt

Claims (1)

(57) [Scope of request for utility model registration] A cable port waterproofing device is attached to a cable channel port at an opening of the cable channel provided with a cable guide tube arranged and fixed immediately before the cable channel port,
A retention structure for a conduit opening waterproofing device, wherein the conduit opening waterproofing device is supported at the other end of a fixture separate from the cable guide tube, one end of which is fixed to the cable guide tube.