JP2003214577A - Coupling of cable protective corrosion resistant lining pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coupling superior in extraction resistant strength and a waterproof effect of a corrosion resistant lining pipe. <P>SOLUTION: Opening both end parts of a coupling body 10 are formed by overhanging in an expansive pipe state as end flanges 11 and 11. Elastic lips 20c and 20c pushed down in a large bending state by the corrosion resistant lining pipe 14 are overhung at an inward almost right angle γ from an inlet part of waterproof rubber packing 20 and 20 integrally fixed to the end flanges 11 and 11 in an internally fitting state, and are strongly press-fitted to an outer peripheral surface of the corrosion resistant lining pipe 14 by its restoring resiliency. While, a screw shaft part 17a of corrosion resistant lining pipe pressing- down bolts 17, 17, 17, and 17 is coated with a waterproof coating film 18, and the tip of the screw shaft part 17a is sharpened as a claw 17b for biting into an element pipe (a steel pipe) 14a of the corrosion resistant lining pipe 14. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyethylene lining unscrewed steel pipe used for cable wiring in water supply / sewerage facilities, chemical factories, laboratories, and other places where corrosion is likely to occur, embedded in the ground, or exposed outdoors. The present invention relates to a coupling for a conduit tube with a polyethylene lining screw (collectively referred to as a corrosion-resistant lining tube for cable protection in the present specification).

[0002]

2. Description of the Related Art Corrosion resistant lining pipes for protecting various cables with product numbers # 16 to 104 are cut at a construction site and conventional couplings used for connecting and connecting them are shown in FIGS. As described above, ring-shaped waterproof rubber packings (2) and (2) are integrally attached to both ends of the opening of the simple cylindrical coupling body (1).

In particular, each of the rubber packings (2) and (2) is clearly shown in the enlarged sectional view extracted in FIG.
Inner diameter (S) that is almost equal to the outer diameter of the coupling body (1)
1) as well as a main coating (2) having a constant length (L1)
a) (2a) and elastic lips (2b) (2b) of a certain length (L2) folded back from the tip of the main coating (2a) (2a) by an angle of about 60 degrees (α) obliquely inward. )
And, from the middle of the elastic lips (2b) (2b), as the inner diameter (S2) which is almost equal to the inner diameter of the coupling body (1), the main coatings (2a) (2a) are stretched in a stepwise parallel state. The fixed length (L3) eaves piece (2
c) and (2c).

Then, the main film (2a) (2a)
Partition protrusions (2d) (2
d) is a main coating (2a) of the main body (2a) of the coupling body (1) under the positioning condition in which it is locked to the opening edge of the coupling body (1).
The base end side of the partition projections (2d) and (2d) of (2a) is fixed to the outer peripheral surface of the coupling body (1) by an adhesive (not shown).

In addition, at least two pairs of longitudinally symmetric interspersed distributions are formed on the body of the coupling body (1) as a pair.
The iron holding bolts (3), (3), (3) and (3) for the corrosion resistant lining pipe, which are respectively screwed in, are set so as to be threaded from the thin neck portion (3a) when receiving the constant tightening torque. The screw shafts (3b) of the holding bolts (3), (3), (3) and (3) which remain as a result, are attached to the main coatings (2a) and (2a) of the rubber packings (2) and (2). ) From thin connecting piece (4) () (4)
Rubber cap (5) that is integrally extended outward through
By (5), it is designed to be covered in a waterproof state.
Reference numerals (5a) and (5a) are conical protrusions that are partially bulged correspondingly to the screw shaft portion (3b) from the flat film surface of the rubber caps (5) and (5).

Reference numeral (6) is a center partition bolt for receiving the cut end surface of the corrosion-resistant lining pipe (7), which is also screwed by being implanted into the body of the coupling body (1). When the screw is retracted, the corrosion-resistant lining pipe (7) relative to the coupling body (1)
The feed pipe of

[0007]

However, such a known coupling for a corrosion-resistant lining pipe still has the following problems.

That is, firstly, the waterproof rubber packing (2)
The elastic lip (2b) (2b) of (2) is shown in FIGS.
As is clear from the usage state of the coupling body (1)
Partitioning projections (2) of the main coatings (2a) (2a) hitting the cut end surface of the corrosion resistant lining pipe (7) inserted into the
d) It can be said that the elastic lip (2b) is pushed to the inner peripheral surface of the tip side with the boundary of (2d) and pushed down so that it is polymerized, so that a restoring force due to the bending deformation is generated. (2b) is the main coating (2a) (2a)
Since it is folded back at an acute angle that is diagonally inward from the tip of the pipe by about 60 degrees (α), the restoring force is weak, and it is strong enough to be crimped to the outer peripheral surface of the corrosion-resistant lining pipe (7). Does not exhibit impact resilience.

Further, when the elastic lips (2b) (2b) are pushed down, the eaves (2c) (2c) additionally projecting from the middle of the elastic lips (2c) (2c) are also joined together and pulled inward from the tip. The eaves piece (2c) (2
With the pulling force of c), the outer peripheral surface of the corrosion-resistant lining pipe (7) cannot be elastically and strongly pressure-bonded.

As a result, the corrosion-resistant lining pipe (7) as a whole
When the pressing bolts (3), (3), (3), and (3) receive the pressing force, the eccentric state is generated with respect to the coupling body (1).
There is a risk of water being flooded inside, and the reliability and stability of the waterproof effect are still inferior.

Paradoxically, if the elastic lips (2b), (2b) have too great a restoring force (if the internal pressure of the corrosion-resistant lining pipe is too strong), they are for waterproofing. Since the rubber packing (2) (2) is attached to the outer peripheral surface of the coupling body (1),
It becomes easy to peel off from the coupling body (1) during use. The threaded shaft portion (3b) of the presser bolts (3), (3), (3) and (3) which remains after being threaded is attached to the rubber cap (5).
In order to cover it with (5), the rubber packings (2) and (2) themselves must be attached to and integrated with the outer peripheral surface of the coupling body (1).

Second, the rubber packing (2) (2)
With the rubber caps (5) and (5) integrally and outwardly extended from the main coatings (2a) and (2a), the remaining screw shaft portion (3b) of the holding bolts (3), (3), (3) and (3). )
The rubber caps (5) and (5) must be pressed and fixed to the outer peripheral surface of the coupling body (1) with separate adhesive tapes (not shown) in order to cover them. It is troublesome in terms of work.

Even if the above-mentioned adhesive tape is used for pressing and fixing, the iron pressing bolt (due to peeling off due to aging of the tape and accidental breakage of the thin connecting pieces (4) and (4)). 3) (3) (3) (3) screw shaft part (3
It is inevitable that b) is easily exposed, causing rusting of the screw shaft portion (3b) and water intrusion into the coupling body (1) along with it.

Third, each presser bolt (3) (3) (3)
(3) As suggested by FIG. 15 as itself, the flat tip surface (3c) of the screw shaft portion (3b) has a polyethylene lining film (7) of the corrosion-resistant lining pipe (7).
It just presses down b), and its raw pipe (steel pipe) (7a)
Since the corrosion-resistant lining pipe (7) is poor in pull-out resistance, it is impossible to function as a grounding earth for leakage prevention because it does not even exert a biting force.

[0015]

DISCLOSURE OF THE INVENTION The present invention intends to improve the above-mentioned various problems, and has a structure for that purpose, which is a cylindrical coupling in which a corrosion-resistant lining coating is applied to the inner peripheral surface and the outer peripheral surface of a steel pipe. Body and

A center partition screw for receiving the corrosion-resistant lining pipe, which is screwed into the center of the body of the coupling body so as to be able to move back and forth.

Similarly, at least two pairs of symmetrically distributed distributions are formed on the body of the coupling body, and a pair of presser bolts for the corrosion-resistant lining pipe are inserted and screwed in such a manner that they can be moved back and forth.

A pair of front and rear waterproof rubber packings are integrally attached to both ends of the opening of the coupling body,

In a coupling in which the outer peripheral surface of a cable-protecting corrosion-resistant lining tube inserted into the coupling body from the front-rear direction is pressed by the pressing bolt,

Both ends of the opening of the coupling body are formed as a pair of front and rear end flanges so as to project in a pipe expanding state.

Basically, each of the above-mentioned waterproof rubber packings is composed of an insert leg membrane which is attached and integrated to the inner peripheral surface of the end flange, and a cover head which is also attached and integrated to the opening edge of the end flange. With an L-shaped cross section,

An elastic lip, which is pushed down from the intersecting inlet portion by the corrosion-resistant lining pipe in a state of being bent by about 90 degrees, is projected inward at a substantially right angle, and the outer periphery of the corrosion-resistant lining pipe is restored by the restoring repulsive force of its deforming action. While stipulating that it be strongly crimped to the surface,

Each of the above holding bolts is made of a metal product such as stainless steel that does not rust, and its screw shaft portion is coated with a waterproof film, and the tip of the screw shaft portion is sharpened as a conical biting claw. Due to

When each of the presser bolts is screwed, the biting claws penetrate the corrosion-resistant lining film of the corrosion-resistant lining pipe to bite the steel pipe of the raw pipe to make a grounding action. To do.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION The specific constitution of the present invention will be described in detail below with reference to the drawings. FIGS. 1 to 8 show the assembled state of the corrosion-resistant lining pipe coupling, and (10) shows a constant length. Thickness (L4) (for example, about 105 mm) and thickness (T1)
(For example, about 2.3 mm) and inner diameter (S3) (for example, about 5 mm)
It is a cylindrical type coupling body having a diameter of 0.2 mm) and is made of a steel pipe (base pipe) (10a), and a fixed length (L5) (for example, about 7 mm) at both ends of the opening is formed by plastic working. A pair of front and rear end flanges (11) and (11) each having a diameter increased by a certain amount (H1) (for example, about 2 mm) are formed in an expanded state.

(12), (12), (12), and (12) are in a longitudinally symmetrical and laterally symmetric dotted distribution state, and have a constant height (H2) from the body of the coupling body (10) (for example, about 1. 5 mm), which are cut and raised outward (Fig.
4 is a total of 4 screw cap cylinders for receiving presser bolts, and the left and right pairs of them have a constant crossing angle (β) (for example, about 60 degrees) when viewed from the front-back direction of the coupling body (10). I keep it.

On the longitudinal centerline of the coupling body (10) that bisects the intersection angle (β), one center partition screw receiving screw hole (at the center of the body of the coupling body (10) ( 13) is also drilled.

However, in the case of a comparatively thin coupling (product numbers # 16 to 28) as shown in FIG. 5 corresponding to FIG. 4, the screw cap sleeves (12) (12) for receiving the holding bolts are symmetrical with respect to the front and rear. A pair of two may be cut and raised from the coupling body (10), and the center partitioning screw receiving screw hole (13) may be interposed in the intermediate portion of the pair of two.

In any case, the outer peripheral surface and the inner peripheral surface including both end flanges (11) and (11) of the coupling body (10) are coated with a corrosion resistant lining film (10b) by powder coating of polyethylene or the like. ) Is applied to form a layered structure with the raw pipe (steel pipe) (10a). still,
The corrosion-resistant lining pipe (14) for cable protection is also a literal pipe (steel pipe) (14a) having a corrosion-resistant lining film (14b) such as polyethylene on the outer peripheral surface and the inner peripheral surface.

(15) is the coupling body (10)
The center partition screw for receiving the corrosion-resistant lining pipe, which is screwed into the center partition screw receiving screw hole (13) through the O-ring (16) for waterproofing so as to move forward and backward, and its coupling body. The screw shaft portion (15a) protruding from the inner peripheral surface of (10) receives the cut end surface of the corrosion-resistant lining pipe (14).

Therefore, by screwing the screw shaft (15a), the screw shaft (15a) is moved to the coupling body (1).
By immersing the corrosion-resistant lining pipe (14) into the coupling body (10), the corrosion-resistant lining pipe (14) can be penetrated. (15b) is a conical head with a large diameter of the center partitioning screw (15), and needless to say, is provided with a locking concave groove (15c) for a rotary operation tool.

(17) (17) (17) (17) are screw cap cylinders (12) (12) (1) for receiving the holding bolts.
2) Corrosion-resistant lining presser bolts, which are screwed into the coupling body (10) along the centripetal direction of the coupling body (10) so that they can be moved back and forth, and are made of stainless steel or other non-rusting metal.

Moreover, as shown in the enlarged view of FIG. 2, the screw shaft portion (17b) of each of the holding bolts (17), (17), (17), (17) has an acrylic resin or a fluorine resin (Teflon (registered trademark)). )) Etc. is coated (welded) and the tip of the screw shaft (17a) is a conical bite claw (17b), which serves as a lining film for the corrosion-resistant lining pipe (14). It is also sharpened so as to cut through (14b) and bite into the raw pipe (steel pipe) (14a). (17c) is each holding bolt (17)
(17) (17) Larger hexagonal head of (17), (19)
(19) (19) (19) are the respective holding bolts (17)
(17) (17) A spring washer inserted and set in (17).

Further, (20) and (20) are a pair of front and rear rubber packings for waterproofing both ends of the opening of the coupling body (10), both of which are, as apparent from the enlarged view of FIG. By having an outer diameter (D1) (for example, about 58.8 mm) approximately equal to the outer diameter of the flange (11) (11), the end flange (11) (11)
Ring-shaped cover head (2
0a) (20a) and the same end flange (11)
Outer diameter (D2) that is almost equal to the inner diameter of (11) (for example, about 5
4.8 mm), the L-shaped basic cross section is continuous with the ring-shaped insertion leg membrane (20b) (20b) that is inserted and fitted into the inner peripheral surface of the end flange (11) (11). The mold is integrally formed of ethylene propylene rubber (EPM) which is rich in impact resilience, weather resistance, tear resistance and the like.

Then, the waterproof rubber packing (2
0) and (20) are inserted into the large-diameter end flanges (11) and (11) of the coupling body (10) from the front-rear direction, and the insertion leg membranes (20b) and (20b) are attached to the first adhesive (21). ) (21) through the end flange (1
1) Attached to the inner peripheral surface of (11) and integrated,
The back surface of the remaining cover heads (20a) (20a) is also attached and fixed to the opening edges of the end flanges (11) (11) by the second adhesives (22) (22). The fixed length (L6) of the insertion leg membrane (20b) (20b) is, for example, about 5 mm, and the fixed length of the end flanges (11) and (11) protruding from the coupling body (10) as shown in FIGS. It is slightly shorter than the size (L5) (about 7 mm exemplified above).

Reference numerals (20c) and (20c) denote the cover heads (20a) and (20a) and the insertion foot membranes (20b) and (20).
a certain amount (H3) continuously from the entrance where it intersects with b)
(For example, about 4 mm) is an elastic lip protruding inwardly at a substantially right angle (γ), and the diameter (S4) at the protruding tip portion is, for example, about 44.2 mm. Inner Diameter (S3) (Approximately 50.
2 mm).

That is, each rubber packing (20) (2
The elastic lip (20c) (20c) of (0) always protrudes from the inner peripheral surface of the coupling body (10), so that the cut end surface of the corrosion resistant lining pipe (14) inserted into the coupling body (10) is When it hits, it is pushed down by about 90 degrees to bend itself, and due to the restoring repulsive force of its deforming action, it strongly presses the outer surface of the corrosion-resistant lining pipe (14) at 360 degrees as a whole. -ing

Further, each of the rubber packings (20), (20) is provided with the fixed length (L6), and the insertion leg membrane (20b).
The thickness (T2) of (20b) is, for example, about 1.3 mm,
Compared with the protrusion amount (H1) of the end flanges (11) and (11) protruding from the coupling body (10) (about 2 mm as exemplified above), the wall thickness is smaller and the insertion foot membrane ( Support protrusions (20d) (20d) for the corrosion-resistant lining pipe from the innermost end of (20b) (20b)
However, it is also projected continuously inward, for example, by about 1 mm. Diameter (S) at the supporting protrusions (20d) (20d)
5) is, for example, about 48.2 mm, and the inner diameter (S3) of the coupling body (10) (about 50.2 m illustrated above)
a little smaller than m).

As suggested from FIGS. 6 and 8, the concave circumferential groove (20) relative to the supporting projections (20d) (20d) thereof.
e) Insertion leg membrane (20b) which is depressed as (20e)
On the inner peripheral surface of (20b), the above corrosion-resistant lining pipe (14)
Elastic lip (20c) (20c) pushed down by
However, it is possible to allow them to escape and polymerize, and the corrosion-resistant lining pipe (14) has the holding bolts (17) (1).
7) Even if the pressing force of (17) (17) is received, the outer peripheral surface of the supporting projections (20d) (20d) can be elastically supported. However, the supporting protrusions (20) of the corrosion-resistant lining pipe (14)
d) (20d) may be omitted even if its installation is omitted.

Thickness (T3) of cover heads (20a) (20a) forming the rubber packings (20) (20)
Is, for example, about 3.8 mm, and the insertion leg membrane (20b) (2
0b) having a thickness (T2) (about 1.3 mm exemplified above), and also includes the elastic lips (20c) (20c) protruding inward from an inlet portion where the both intersect. It is preferable that the thickness of the elastic lips (20c) (20c) is set to a tapered state of, for example, about 1.0 mm to 1.5 mm by shaping the entire surface as a convex curved surface as shown in FIG.

It is possible to cover the elastic lips (20c) by the corrosion-resistant lining pipe (14) so that the elastic lips (20c) (20c) can be appropriately bent and deformed.
c) (20c) is greatly pushed down in a state of being bent by about 90 degrees to cause a strong restoring resilience, but there is a risk that the rubber packings (20) (20) may peel off. This is because it can be effectively prevented by the heads (20a) (20a), which helps improve the support strength and durability of the rubber packing (20) (20).

The numerical values of the dimensions exemplified above are the product number # 42.
Needless to say, it is different and changes in size depending on various product numbers.

Since the corrosion-resistant lining pipe coupling of the present invention is constructed as described above, the screw shaft portion (15a) of the center partitioning screw (15) projects from the inner peripheral surface of the coupling body (10). When the anticorrosion lining pipe (14) for cable protection is inserted into the coupling body (10) from the front and rear direction, the cut end face is received by the center partition screw (15). The connection piping state of the corrosion resistant lining pipe (14) as described above can be obtained.

Further, from the inlet portion of the waterproof rubber packing (20) (20) fixedly integrated with the large-diameter end flanges (11) (11) of the coupling body (10) in an internally fitted state, The elastic lips (20c) (20c) project inwardly at a substantially right angle (γ), which collides with the cut end surface of the corrosion-resistant lining pipe (14) to form about 9 mm.
It is pushed down into a state of being greatly bent by 0 degree, and due to the strong restoring resilience that accompanies the deformation action, it will be pressure-bonded to the outer peripheral surface of the corrosion-resistant lining pipe (14) as a whole at 360 degrees, thus ensuring stability. A highly waterproof effect can be achieved.

In that case, waterproof rubber packing (20)
(20) is the first and second adhesives (21) (21) (2) on the inner peripheral surface of the end flanges (11) (11) and the opening edge.
2) It is attached and fixed via (22), and its insertion leg membranes (20b) (20b) are the above corrosion-resistant lining pipes (14) and end flanges (11) (11) of the coupling body (10). Since it will be sandwiched between the inside and outside of the rubber packing (20) (20) during use
Is the end flange (11) of the coupling body (10)
There is no possibility of peeling off from (11).

Finally, the holding bolt (17) (1
7) (17) When the (17) is screwed, the bite claw (17) is sharpened at the tip of the screw shaft (17a).
As shown in FIGS. 6 to 8, b) penetrates the lining film (14b) of the corrosion-resistant lining pipe (14) and bites into the raw pipe (steel pipe) (14a).
In combination with the pressure bonding force of the rubber packings (20) (20), the corrosion resistant lining pipe (14) can exhibit an excellent pull-out resistance, and at the same time, the holding bolt (1).
7) (17) (17) (17) can also function as a ground.

Further, the holding bolts (17) (17)
(17) (17) is a metal product such as stainless steel that does not rust, and since the screw shaft portion (17a) is coated with the waterproof film (18), it follows the screw shaft portion (17a). There is no risk of rainwater entering the inside of the coupling body (10).
The tightening torques of 7), 17), 17), and 17) can be controlled to be constant by the compression deformation degree of the spring washers (19), (19), (19), and (19).

If the center partitioning screw (15) is screwed back and forth, the feed pipe for the corrosion-resistant lining pipe (14) relative to the coupling body (10) can be provided, resulting in a relay box (not shown). It is also possible to conveniently connect the cut end surfaces of the two corrosion-resistant lining pipes (14), which have been sequentially dispatched from the above, to each other at the final point of the piping work without any trouble.

[0049]

As described above, in the present invention, the steel pipe (10
Corrosion-resistant lining film (10b) on the inner and outer peripheral surfaces of a)
A cylindrical coupling body (10) with

A center partition screw (15) for receiving the corrosion-resistant lining pipe, which is screwed into the center of the body of the coupling body (10) so as to be moved forward and backward.

Similarly, as a pair of at least two symmetrically distributed points distributed in the longitudinal direction to the body of the coupling body (10),
Retaining bolts (17), (17), (17), (17) for corrosion-resistant lining pipes, which are respectively inserted and screwed in such a manner that they can be moved forward and backward,

A pair of front and rear waterproof rubber packings (20) (20) integrally attached to both ends of the opening of the coupling body (10) are provided,

Corrosion-resistant lining pipe (1) for cable protection inserted in the coupling body (10) from the front-back direction.
The outer peripheral surface of 4) is attached to the holding bolts (17) (17) (1
7) In the coupling pressed by (17),

Both ends of the opening of the coupling body (10) are formed as a pair of front and rear end flanges (11) and (11) so as to project in a pipe expanding state.

The waterproof rubber packing (20) (2)
0) are attached to the inner peripheral surfaces of the end flanges (11) (11) of the insert flange (20b) (2) to be integrated.
0b) and the cover head (20) which is also attached and integrated to the opening edges of the end flanges (11) and (11).
a) (20a) with a basic L-shaped cross section,

Elastic lips (20c) (20c) pushed down by the above-mentioned corrosion-resistant lining pipe (14) in a state of being bent by about 90 degrees from the intersecting inlets are projected to an inward substantially right angle (γ) to deform the same. While restoring the action, the repulsive force strongly presses the outer peripheral surface of the corrosion-resistant lining pipe (14).

The holding bolts (17) (17) (17)
Each of the items (17) is a metal product such as stainless steel that does not rust, and a waterproof film (18) is provided on the screw shaft portion (17a).
And the screw shaft part (17a)
By sharpening the tip of the cone as a conical bite claw (17b),

The holding bolts (17) (17) (17)
When each of the (17) is screwed, the bite (17)
9A to 9C, since b) penetrates the corrosion-resistant lining film (14b) of the corrosion-resistant lining pipe (14) and bites and acts on the steel pipe (14a) of the raw pipe.
There is an effect that the problems of the prior art described based on 5 can be completely improved.

That is, according to the above configuration of the present invention, the waterproof rubber packing (20) (2) having a basic L-shaped cross section.
The insert foot membrane (20b) (20b) of (0) is attached and integrated with the inner peripheral surface of the end flanges (11) and (11) protruding from both ends of the opening of the coupling body (10), and the same rubber packing ( 20) The cover heads (20a) (20a) of (20) are the end flanges (11).
Since the rubber packings (20) and (20) are inserted and integrated into the opening edge of (11), the insertion leg membranes (20b) and (20b) of the rubber packing (20) are inserted into the coupling body (10). During use, the corrosion-resistant lining pipe (14) is sandwiched between the coupling body (10) and the inside and outside of the coupling body (10), and as a result, the waterproof rubber packings (20) (20) come off from the coupling body (10). There is no fear.

Also because of that, the insertion leg membranes (20b) (20) in the rubber packings (20) (20).
The elastic lips (20c) (20c) are projected to the inward substantially right angle (γ) from the entrance where the b) and the cover heads (20a) (20a) cross each other and inserted into the coupling body (10). With the corrosion-resistant lining pipe (14), the elastic lip (20c) (20c) (20c) (20) can be pushed down into a state in which the elastic lip (20c) (20c) (20c) is bent to a state in which the elastic lip (20c) (20c) is bent.
Corrosion resistant lining tube (1)
Since it is pressure-bonded to the outer peripheral surface of 4) as a whole at 360 degrees, a waterproof effect with high stability and durability can be obtained. The corrosion resistant lining pipe (14) is attached to the holding bolts (17) (1
7) Even if it is eccentric with the coupling body (10) due to the pressing force of (17) (17), the waterproof effect due to the rubber packing (20) (20) is not lost.

Further, the holding bolts (17), (17), (17) and (17) for the corrosion resistant lining pipe are made of metal such as stainless steel which does not rust, and the screw shaft portion (17a) is provided with the waterproof film (18). Since it is coated, the rubber cap (5) (5) like the prior art mentioned at the beginning
And a coupling body (1) for these with an adhesive tape
There is no need for special and complicated waterproofing work to press and fix to the rubber packing (20) (2).
0) can be fixedly integrated with the large-diameter end flanges (11) and (11) of the coupling body (10) in an internally fitted state.

Moreover, the holding bolts (17) (17)
(17) The tip of the screw shaft portion (17a) in (17) is sharpened as a conical bite claw (17b), and if this is screwed toward the corrosion resistant lining pipe (14), The bite claw (17b) penetrates the corrosion-resistant lining film (14b) of the corrosion-resistant lining pipe (14) and bites and grounds the steel pipe (14a), which is the raw pipe, so that the waterproof rubber packing ( Two
0) (20) combined with the strong crimping force of the elastic lips (20c) (20c), the pull-out resistance of the corrosion-resistant lining pipe (14) can be remarkably improved, and the holding bolt (17) is also provided. (17) (17) (17)
Has the effect that it can also function as a grounding earth for leakage prevention.

In particular, if the configuration of claim 2 is adopted,
Insert the elastic lips (20c) (20c) of the waterproof rubber packings (20) (20), which are pushed down into a state of being greatly bent by about 90 degrees as described above, into the rubber packings (20) (20) with a reduced thickness. Foot membrane (20b)
The rubber packings (20) and (20) can be smoothly evacuated into the concave circumferential grooves (20e) and (20e) of (20b) to be polymerized, and at the same time, the rubber packings (20) and (20) are coupled to the coupling body (10).
There is a risk that it will come off from the plug (20b)
Cover head (20a) thicker than (20b)
By (20a), it can be effectively prevented.

If the structure of claim 3 is adopted, the corrosion resistant lining pipe (14) which receives the pressing force of the pressing bolts (17), (17), (17) and (17) is attached to the coupling body (10). On the other hand, even if it becomes eccentric, the outer peripheral surface of the corrosion-resistant lining pipe (14) is rubber-packed (20) (2).
The support projections (20d) and (20d) that bulge inward from the innermost ends of the insertion leg membranes (20b) and (20b) in (0) can be stably and elastically supported, and the elastic lip (20c) ( In combination with the tapered shape of 20c), there is an effect that the insertion resistance of the corrosion resistant lining pipe (14) with respect to the coupling body (10) can be appropriately maintained.

[Brief description of drawings]

FIG. 1 is a perspective view of a coupling according to the present invention.

FIG. 2 is a partially cutaway front view showing the holding bolt of FIG. 1 in an extracted manner.

FIG. 3 is a half-cutaway sectional view showing the rubber packing of FIG. 1 in an extracted manner.

FIG. 4 is a plan view showing a usage state of FIG.

FIG. 5 is a plan view corresponding to FIG. 4 of the thin coupling.

6 is a sectional view taken along line 6-6 of FIG.

7 is a sectional view taken along line 7-7 of FIG.

FIG. 8 is an enlarged view showing a part of FIG. 6 extracted.

FIG. 9 is a perspective view showing a conventional coupling.

FIG. 10 is a half-cutaway sectional view showing the rubber packing of FIG. 9 in an extracted manner.

FIG. 11 is a front view showing the holding bolt of FIG. 9 in an extracted manner.

12 is a plan view showing the usage state of FIG. 9. FIG.

13 is a sectional view taken along line 13-13 of FIG.

14 is a sectional view taken along line 14-14 of FIG.

FIG. 15 is an enlarged view showing a part of FIG. 13 extracted.

[Explanation of symbols]

(10) ・ Coupling body (10a) · Element pipe (steel pipe) (10b) · Lining film (11) · End flange (14) · Corrosion resistant lining pipe (14a) Element tube (14b) · Corrosion resistant lining film (15) Center partition screw (16) · O-ring (17) · Presser bolt (17a) · Screw shaft (17b) ・ Claw with bite (18) ・ Waterproof film (19) · Spring washers (20) · Rubber packing (20a) Cover head (20b) · Inserted leg membrane (20c) -Elastic lip (20e) ・ Concave circumferential groove (21) First adhesive (22) Second adhesive

Claims (3)

[Claims] 1. A cylindrical coupling body (10) in which a corrosion-resistant lining film (10b) is applied to the inner and outer peripheral surfaces of a steel pipe (10a), and to the center of the body of the coupling body (10). One corrosion-resistant lining pipe receiving center partition screw (15) that is screwed in so that it can be advanced and retracted freely, and at least two pairs of longitudinally symmetrically distributed distribution to the body of the coupling body (10). Corrosion-resistant lining pipe retainer bolts (17), (17), (17), and (17), which are respectively inserted and screwed so that they can be moved forward and backward, and a pair of front and rear waterproofs that are integrally attached to both ends of the opening of the coupling body (10). Rubber packing (20) (2
0) and the outer peripheral surface of the corrosion-resistant lining pipe (14) for cable protection inserted into the coupling body (10) from the front-back direction, the pressing bolts (17) (17) (17) (17)
In the coupling pressed by, the opening ends of the coupling body (10) are formed as a pair of front and rear end flanges (11) and (11) so as to project in a pipe-expanded state, and the waterproof rubber packings (20) and (20) Each piece is attached and integrated to the inner peripheral surface of the end flange (11) (11), and is also integrated into the insertion leg membrane (20b) (20b) and the opening edge of the end flange (11) (11). And a cover head (20a) (20a) formed into a basic L-shaped cross-section, and the corrosion-resistant lining pipe (14) is formed from the intersecting inlet portion.
The elastic lips (20c) (20c) that are pushed down by about 90 degrees due to the bulge are projected to an inward substantially right angle (γ), and the outer peripheral surface of the corrosion-resistant lining pipe (14) is restored by the restitution force of the deforming action. On the other hand, each of the presser bolts (17), (17), (17) and (17) is a metal product that does not rust, such as stainless steel, and a waterproof film (18a) is formed on the screw shaft portion (17a). ) Is coated, and the tip of the screw shaft portion (17a) is sharpened as a conical bite claw (17b), so that the above-mentioned presser bolts (17) (17) (17) (17) are screwed respectively. When the advancing operation is performed, the bite claw (17b) cuts through the corrosion resistant lining film (14b) of the corrosion resistant lining pipe (14) and bites the steel pipe (14a) of the raw pipe to ground. Coupling of corrosion-resistant lining pipe for cable protection, which is characterized to work. 2. A cover head (20a) for covering the insertion leg membranes (20b) (20b) of each rubber packing (20) (20).
Support projections (20d) (20d) (20d) for a corrosion-resistant lining pipe, which are thinner than (20a) and bulge inward from the rear end thereof.
Concave peripheral groove (20e) (20e) that is depressed relative to d)
2. The coupling of a corrosion-resistant lining pipe for cable protection according to claim 1, wherein the elastic lip (20c) (20c) pushed down by the corrosion-resistant lining pipe (14) escapes and polymerizes. 3. A support protrusion (20d) for a corrosion resistant lining pipe.
(20d) slightly bulges from the inner peripheral surface of the coupling body (10), and elastic lips (20c) (20c)
The coupling of the corrosion-resistant lining pipe for cable protection according to claim 2, characterized in that the tape is formed in a tapered shape.