JPH1026272A - Pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the deposit of sludge in a clearance between an innermost end of a receive port part and a tip of an insertion port part to avoid the corrosion of a pipe body by providing a dust seal having elastic restoration force or expansion and shrinkage property in the clearance in a pipe joint in which the insertion port part of one pipe body is fitted in the receive port part of the other pipe body in play. SOLUTION: In a pipe joint which is used in a joint part of pipe bodies in service water works and sewage work, a dust seal 8 made of spongelike rubber or synthetic resin having elastic restoration force, closed cells, or water permeation property is provided in a ringlike clearance 6 formed between an innermost end of a receive port part 1a of one pipe body 1 and a tip of an insertion port part 2a of the other pipe body 2. At this time, the dust seal 8 is fixed firmly to either or both of the receive port part 1a and the insertion port part 2a and is inserted in a condition in which it is compressed so that it forms substantially the same face as inner faces of both pipe bodies 1, 2. By blocking the clearance 6 by the dust seal 8 in this way, it is possible to prevent the deposit of sludge, in particular, in a clearance in a pipe bottom part and the corrosion of both pipe bodies 1, 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a sewer system, a water system,
Also, the present invention relates to a pipe joint used for a joint portion between pipe bodies such as industrial water, and particularly relates to a pipe joint in which sludge or the like is prevented from being deposited.

[0002]

2. Description of the Related Art A pipe shown in FIG. 5, for example, is used for piping of a pipeline such as a sewer. That is, the insertion portion 2a at the end of the other tube 2 is inserted into the large-diameter reception portion 1a formed at the end of one tube 1 connected to each other over a predetermined length, A tube having a structure in which a gap between the receiving portion 1a and the insertion portion 2a is sealed with a packing 3 is used.

[0003] When a fluid pressure acts on the pipe, a pressing ring 5 having a separation preventing claw 4 for pressing the packing 3 and preventing the two pipes 1 and 2 from coming off is used.

[0004]

In the above-described pipe joint, a required clearance is provided between the receiving portion 1a and the insertion portion 2a in order to be buried in soft ground or to absorb vibrations such as earthquakes. Is provided so that the joint can be slightly bent.

[0005] Therefore, the back end of the receiving portion 1a and the insertion portion 2a
It is unavoidable that a step-shaped gap 6 is formed between the front end portion and the front end portion. When such a gap 6 is present, when the pipes 1 and 2 are formed of ductile cast iron, and when piping is performed as sewerage or industrial water, sludge 7 is deposited in the gap 6 at the bottom of the pipe, and the pipes 1 and 2 are removed. In addition, the length of expansion and contraction is limited in the case of a pipe joint which is allowed to expand and contract and to be hardly bent.

As a solution to this problem, there is a pipe joint disclosed in, for example, JP-A-7-286693 and JP-A-8-14477.

[0007] Each of the conventional pipe joints has a double pipe structure in which a cylindrical body is inserted into the pipes of the receiving part and the insertion part of both pipes to close the gap. For,
Not only does the opening area of the flow path become smaller at the joint, but also a step is formed in the pipe by a tubular body, and sludge may accumulate on this step.

The present invention has been made in view of the same problems in the above-mentioned flexible type pipe joints, telescopic type pipe joints, and telescopic flexible type pipe joints. The formed gap is reduced the opening area of the flow path,
Provided is a pipe joint that prevents sludge accumulation that is a factor in restricting expansion and contraction and flexibility of the pipe joint without forming a step portion, and also prevents corrosion of the pipe due to sludge accumulation. It is intended to be.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a large-diameter socket formed at the open end of one tube, and the open end of the other tube. Insertion of the
In a pipe fitting which is loosely fitted while maintaining watertightness, at least at the pipe bottom in an annular gap formed between the inner end of the receptacle and the tip of the insertion port, elastic restoring force or elasticity And a dust seal having:

It is preferable that a part of the dust seal is fixed to at least one of the receiving portion and the insertion portion.

Further, another pipe joint of the present invention is characterized in that a small-diameter pipe is kept water-tight within at least one open end of a large-diameter pipe of a predetermined length, and is movable in the axial direction of the pipe. In a pipe joint which is loosely fitted so as to be able to bend, a dust seal having an elastic restoring force or elasticity is provided at least on the bottom of the inner peripheral surface of the large-diameter pipe near the opening end of the small-diameter pipe. Is fixed so that at least one end thereof is inserted into a gap between the inner peripheral surface of the large diameter pipe and the outer peripheral surface of the small diameter pipe.

It is preferable that the dust seal in each of the pipe joints is provided so as to be substantially flush with the inner surface of the pipe.

It is preferable that the dust seal in each of the above pipe joints is a soft sponge or spongy substance.

According to each of the pipe joints of the present invention, each of the dust seals forms a gap between the deep end of the receiving portion and the tip of the insertion portion, and a gap between the loose fitting portion between the large-diameter pipe and the small-diameter pipe. Since the pipe is closed, sludge or the like is prevented from being deposited in the gap at the bottom of the pipe, and the pipe does not corrode or lose its flexibility.

In addition, the pipe body may be elongated at the joint,
Even if the gap expands due to bending or the like, the dust seal deforms and closes the gap accordingly, so that the effect of preventing the accumulation of sludge or the like is not impaired.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of the present invention. Since this embodiment is an improvement on the conventional pipe joint shown in FIG. 5, the same members as those shown in FIG. The detailed description is omitted.

An annular gap 6 formed between the back end of the receiving portion 1a of one tube 1 and the tip of the insertion portion 2a of the other tube 2 has elastic restoring force and independent The sponge (sponge) rubber or synthetic resin dust seal 8 having a bubble or water permeability is fixed to one or both of the receiving portion 1a and the insertion portion 2a, so that the two tubes 1, 2 Is inserted in a compressed state so as to be substantially flush with the inner surface of the.

When the dust seal 8 is fixed to both the receiving portion 1a and the insertion portion 2a, it is not necessary to have an elastic restoring force, but it is only necessary to have elasticity. Further, the dust seal 8 may be a foam having elasticity, for example, a soft urethane foam.

In the pipe joint of the first embodiment described above, the spongy dust seal 8 closes the gap 6 between the inner end of the receiving portion 1a and the tip of the insertion portion 2a. There is no danger of sludge or the like accumulating in the gap at the bottom of the tube, and therefore, corrosion of the tubes 1 and 2 is prevented.

The pipes 1 and 2 are bent at the joint,
Even if the gap 6 becomes large, or as shown in FIG. 2, the dust seal 8 expands or expands elastically even if the gap 6 is expanded due to the force of the pipes 1 and 2 being pulled out by the fluid pressure in the pipe to exert a pulling force. Thus, since the gap 6 is always closed, the effect of preventing the accumulation of sludge or the like is not impaired.

Further, if the dust seal 8 has water permeability, the inner surface of the receiving portion 1a and the insertion portion 2a
The fluid that has entered the gap 9 with the outer peripheral surface of the tube 1 is easily discharged when the joint is bent, and the resistance when the tubes 1 and 2 expand and contract or flex is not increased.

If the dust seal 8 has a closed-cell sponge-like shape, water does not enter the dust seal 8, so that the inside of the dust seal 8 may be clogged due to the passage of water like a water-permeable one. In addition, the durability of the dust seal is improved.

FIG. 3 shows a second embodiment of the present invention, which is applied to a flexible joint.

A pair of left and right spigot pipes (small diameter pipes) 11 each having a flange 11a at the outer end are loosely fitted in the sleeve (large diameter pipe) 10 with their opposing ends separated by a predetermined distance. . A rubber packing 12 is inserted between both open ends of the sleeve 10 and the outer peripheral surface of each spigot tube 11.

Reference numeral 13 denotes a pressing ring, which presses the packing 12 by engaging a holding bolt 14 with a mounting piece 10a connected to both ends of the sleeve 10 to fasten the packing 12 to reduce a gap between the spigot tube 11 and the sleeve 10. Sealed.

The two spigot tubes 11 can move in the tube axis direction in the sleeve 10 and can be bent within the range of the gap with the sleeve 10.

A sponge-like dust seal 8 is provided on the inner peripheral surface of the central portion of the sleeve 10 in the same manner as in the above embodiment.
1 and are inserted in a compressed state into gaps 15 between the outer peripheral surface of the opposing end of each spigot tube 11 and the inner peripheral surface of the sleeve 10. It is fixed.

When such a cylindrical dust seal 8 is provided, the gap 15 is completely closed, so that sludge or the like is prevented from entering and accumulating in the gap at the bottom of the joint, and the spigot tube 11 and the sleeve Corrosion of the spigot tube 11 is prevented, and the flexibility of the spigot tube 11 is not impaired.

When the spigot tube 11 moves in the tube axis direction with respect to the sleeve 10, the dust seal 8 is also elastically deformed, so that the sealing performance is not impaired.

Further, as shown in FIG. 4, even if the spigot tube 11 bends vertically and the gap 15 at the bottom of the tube expands, the dust seal 8 expands or expands elastically, and
5 is always closed, so that the effect of preventing intrusion of sludge or the like does not deteriorate.

The present invention is not limited to the above embodiment.

For example, in each of the above-described embodiments, the dust seal 8 is provided so as to close the entire circumference of the gap. The dust seal 8 may be provided only at the bottom of the tube.

In the second embodiment, a double-flanged pipe joint composed of a pair of spigot pipes 11 and a sleeve 10 is used. However, the present invention is also applied to a pipe joint composed of one spigot pipe and a sleeve with a flange. be able to.

[0034]

According to the present invention, the following effects can be obtained.

(A) According to the first and third aspects of the present invention, the gap between the deep end of the receiving port and the tip of the insertion port and the gap between the large-diameter pipe and the small-diameter pipe are formed by dust sealing. The blockage prevents sludge and the like from accumulating in the conventional case, thereby preventing the pipe body from being corroded and the flexibility from being impaired.

(B) Further, since the dust seal has an elastic restoring force or elasticity, even if the gap expands due to elongation of the tubular body, the gap is always closed by deformation of the dust seal, and sludge or the like is formed. There is no loss of the effect of preventing the deposition.

(C) According to the second aspect, the dust seal is deformed in accordance with the movement of the tube even if the tube is greatly expanded or contracted or bent, so that the gap is securely closed.

(D) According to the fourth aspect, a step is formed in the pipeline, so that sludge is prevented from being deposited on the step, and the opening area of the flow path is prevented from being reduced. .

(E) According to the fifth aspect, it is possible to prevent the dust seal from becoming a resistance when the tube expands and contracts or bends.

[0040]

[Brief description of the drawings]

FIG. 1 is a central longitudinal sectional side view showing a first embodiment of the present invention.

FIG. 2 is a central longitudinal sectional side view when the joint is extended.

FIG. 3 is a central vertical sectional side view showing a second embodiment of the present invention.

FIG. 4 is a central vertical cross-sectional side view showing a state in which the joint portion is bent in the vertical direction.

FIG. 5 is a central longitudinal sectional side view showing a conventional pipe joint.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 2 Tube 1a Receiving part 2a Inserting part 3 Packing 4 Detachment preventing claw 5 Pressing ring 6 Gap 7 Sludge 8 Dust seal 9 Gap 10 Sleeve 10 (Large diameter pipe) 10a Mounting piece 11 Spigot pipe (Small diameter pipe) 11a Flange 12 Packing 13 Pressing wheel 14 Holding bolt 15 Clearance

Claims (5)

[Claims] 1. A large-diameter socket formed at an open end of one tubular body has an insertion portion at an open end of the other tubular body.
In a pipe fitting which is loosely fitted while maintaining water tightness, an elastic restoring force or elasticity is provided at least at a pipe bottom in an annular gap formed between a back end of the receiving portion and a tip of the insertion portion. A pipe joint comprising a dust seal having: 2. The pipe joint according to claim 1, wherein a part of the dust seal is fixed to at least one of the receiving portion and the insertion portion. 3. A small-diameter pipe is provided in at least one open end of a large-diameter pipe having a predetermined length so as to maintain watertightness, to be movable in an axial direction of the pipe, and to bendable with respect to the large-diameter pipe. In a pipe joint which is loosely fitted, at least one end of the dust seal having elastic restoring force or elasticity is provided at least on the bottom of the inner peripheral surface of the large diameter pipe near the open end of the small diameter pipe. A pipe joint characterized by being inserted and fixed in a gap between an inner peripheral surface of a large diameter pipe and an outer peripheral surface of a small diameter pipe. 4. The flexible pipe joint according to claim 1, wherein the dust seal is provided so as to be substantially flush with the inner surface of the conduit. 5. The pipe joint according to claim 1, wherein the dust seal is a soft sponge or a spongy substance.