JP2824637B2 - Metal tube fittings for soft tubes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal pipe joint for a soft tube.

[0002]

2. Description of the Related Art Recently, resin tubes such as polybutene tubes, PVC tubes, and polyethylene tubes have been used in place of metal tubes used as water supply or hot water supply tubes.

[0003] That is, conventionally, when connecting a copper tube to a faucet, it has been necessary to bend, bend, or braze it into a predetermined shape and connect it. In such a case, it is said that these operations become unnecessary, and that interference with other members on the piping can be avoided, and that the piping work can be extremely easily performed (for example, in Japanese Utility Model No.
26451, Japanese Utility Model Publication 7-21664, etc.).

By the way, even a resin tube having such a characteristic cannot be used for a hot water supply pipe requiring heat resistance.
Recently, polybutene tubing (polyolefin resin, not only corrosion resistance but also high strength at high temperature, which is ultra high molecular weight, but has high flexibility, heat creep resistance and stress crack resistance. ) Has been standardized so that it can be used for water supply and hot water supply pipes (see JIS K6778).

Therefore, this polybutene tube is
It has become widely used, including heating pipes for greenhouses and vinyl houses, and floor heating and cooling pipes for houses and livestock sheds.

[0006] By the way, in order to connect a polybud tube to another pipe type or a metal appliance, a metal pipe joint is required. At that time, unlike a copper pipe, the polybud tube is free after the construction. -It is extremely convenient because it can be made to be able to swing positively in response to an earthquake, but it is very convenient, but instead, consideration is given to water leakage and escape at the joint with the pipe joint There is a need to.

On the other hand, various proposals have been made for metal pipe joints for joining general resin tubes (for example, Japanese Utility Model Application Laid-Open No. 58-172178 and Japanese Utility Model Application Laid-Open No. 61-6).
6288, JP-A-2-163592, etc.).

[0008] One of such proposals is Japanese Utility Model Laid-Open No. 6-32.
No. 887 describes a metal pipe joint.

In the enlarged view of the metal pipe joint shown in FIG. 6, a joint body 51 of the pipe joint 50 has a threaded portion 52 for mounting at one end and a sawtooth 53 at the other end, and has a coarse pitch. A tube insertion portion 55 composed of a groove 54 is formed integrally with each other, and a nut portion 56 is formed substantially in the middle of these.

The tube insertion portion 55 has a resin tube 5.
7 is externally fitted and press-fitted, a C-shaped collar 58 is externally fitted to the outer fitted portion, and a C-shaped tightening member 59 is further externally fitted to the C-shaped collar 58 and tightened by a bolt 60. .

The C-shaped tightening member 59 has a C-shaped opening formed in parallel with the axial direction, and the C-shaped opening 1 is formed.
The bolt 60 is inserted through the pair of outward flange portions 61 and screwed into a nut (not shown), and the outward flange portions 61 are brought closer to each other and fastened. Reference numeral 62 denotes an O-ring.

Therefore, according to the pipe joint 50,
When the bolt 60 is tightened while being visually observed, the C-shaped tightening member 5
Since the C-shaped collar 58 is interposed between the resin tube 9 and the resin tube 57, the diameter of the C-shaped collar 58 is reduced and the resin tube is reduced.
The tube 57 is uniformly tightened to the tube insertion portion 55,
Of the resin tube by the circumferential groove 54 etc.
The protrusion 57 is prevented from slipping out.

[0013]

However, the metal pipe joint 50 has the following problems. When a pair of outward flanges 61 (for example, made of SUS having a thickness of 1.2 mm) 61 forming a C-shaped opening are strongly tightened with bolts 60 having an outer diameter of 5 mmφ, for example, a SU having a thickness of 1.2 mm is obtained.
Even if an S-shaped C-shaped collar 58 is interposed, this bolt 6
Since there is no limitation on the tightening torque of 0 and the parallelism of the outward flange portion 61 is deformed so that tightening can be performed, the interposed C-shaped collar 58 becomes elliptical, and the resin tube is formed. There was a problem that wrinkles were formed on the 57 and sealability was impaired.

In order to limit the tightening torque of a general tightening nut, it is known that a member to be broken (also referred to as a breakable piece) is broken when a predetermined tightening torque is exceeded. For example, Japanese Patent Publication No. 48-24973,
However, such a tightening torque limiting device cannot be employed because it is not a soft tube tightening bolt.

[0015]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in order to solve such a problem, and the gist of the present invention is to provide a metal joint body integrally formed with a tube insertion portion, A C-shaped tightening member for tightening a soft tube fitted externally to the tube insertion portion and extending a pair of outward flanges which are opposed to each other and are close to each other at the time of tightening; A bolt insertion hole is drilled in the outward flange portion, a nut is provided in the other outward flange portion, and the nut is inserted into the bolt insertion hole, and screwed to the nut to make these outward flange portions approach. In the metal tube fitting for a soft tube comprising a bolt to be tightened, the soft tube is tightened at the C-shaped opening of the C-shaped tightening member by the pair of outward flange portions when the bolt is tightened. The movable inner piece is clamped, and the piece A metal pipe joint for a soft tube, wherein a breakable piece that breaks when the outward flange portion is tightened is integrally provided at an outer end to limit a bolt tightening torque. It is in.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to embodiments shown in the accompanying drawings. FIG. 1 is an exploded perspective view of an embodiment of the present invention, and FIG.
(A) is a state diagram before tightening, (B) is a state diagram after tightening, FIG. 3 is an enlarged detailed view of a main part of FIG. 2, (A) is a plan view, (B)
Is a side view of (A), (C) is an X sectional view of (A), (D)
4 is a perspective view of (A), and FIG. 4 is another embodiment of FIG.
Is a plan view, (B) is a side view of (A), (C) is an X sectional view of (A), FIG. 5 is a detailed view of another main part of FIG. 2, (A) is a plan view, (B) () Is a view taken in the direction of the arrow Y in (A), and the description of the same parts and equivalent parts as in FIG. 6 showing the conventional example is omitted.

The pipe joint of the present invention has a nominal diameter of 10 mmφ to 3 mm.
It is suitable for a brass or SUS pipe joint for connecting a 0 mmφ, particularly a 13 mmφ or 15 mmφ polybud tube.

It is convenient to connect the polydub tube or the pipe joint to a floor heating / cooling (for passing tap water) header. Can be.

Further, in this pipe joint, a polybutene tube is used.
Instead of a tube, a thin copper tube can be used.

Accordingly, a resin tube such as a polybutene tube and a thin copper tube are collectively referred to as a soft tube in this specification.

First, an outline of the pipe joint 1 according to the embodiment of the present invention will be described. In particular, in FIGS. 1 and 2, the fitting body 2 of the pipe fitting 1 has, on one end side, a mounting screw portion 3 for mounting to, for example, a header pipe (not shown), and a polybuten tube 4 on the other end side. And a tube insertion portion 5 for forming the same.

The tube insertion portion 5 has an O-ring groove 7 located at the center in the axial direction, a retaining ridge 8 provided at the outer end thereof, and a set for adjusting the diameter of the polytube 4. A recess (not shown) on the side of the nut 6 into which the link 9 is fitted is formed.

On the other hand, the C-shaped tightening member 11 for directly tightening the polydentate tube 4 inserted into the joint body 2 is S
It is made of US sheet metal (not necessarily made of sheet metal and may be a metal cut product), and its C-shaped opening 12
Are extended outwardly from each other such that they are parallel to the axial direction.

These outward flange portions 13 and 13A have bolt insertion holes 15 and 1 slightly larger than the outer diameter of the bolt 14.
5, and a nut 16 is welded to the opposite back surface of the one outward flange portion 13A. If the C-shaped fastening member 11 is a metal-cut product, the nut 16 may be simply threaded.

Therefore, these outward flanges 1
When the bolt 14 is inserted through the bolt insertion hole 15 of 3, 3A and screwed into the nut 16, the outward flange 13, 1
3A approach each other, and as a result, the inserted polytube tube 4 is fastened to the tube insertion portion 5 by the diameter reduction of the C-shaped fastening member 11.

The structure and operation of the above-described pipe joint 1 are the same as those of the conventional pipe joint 5 shown in FIG.
It is almost the same as 0.

Here, the C-shaped tightening member 11
In particular, the following configuration is adopted to uniformly tighten the entire circumference of the polydentate tube 4 in the C-shaped opening 12.

That is, a pair of outward flange portions 13,
As shown in FIG. 5, 13A is integrally extended by sheet metal working from both ends of the fastening member main body 17 divided into two ridges 17A and 17A, and both sides thereof (refer to the axial side of the pipe joint 1). The same shall apply hereinafter) to the outwardly extending flange 1
In the case of No. 3, the bolt 14 is formed downward (the head of the bolt 14 is set to the top; the same applies hereinafter), and in the case of the outward flange portion 13A, it is formed upward. Therefore, four bending claws 18 are formed.

It should be noted that the fastening member main body 17 is
7A, the O-ring 27 shown in FIG. 1 can be tightened on both sides thereof, and the tightening member body 17 can be easily bent. Therefore, the arc surface 24 of the later-described piece 22 is also formed in a fork shape (see FIGS. 3A and 4A).

As shown in FIG. 2, the bent claws 18 formed in the same substantially trapezoidal shape as shown in FIG. 2 have an inclined cam surface 19 inclined (45 °) so as to expand toward the base thereof. A leading edge 20 parallel to the surface of the outward flange portion 13 and capable of contacting the leading edge 20 of the other bending claw 18 facing the outer edge portion, and an outer edge perpendicular to the surface of the outward flange portion 13 21.

The four bent claws 18, 18,... Are made of a resin such as the following nylon (trade name). Are cut along the break line of the breakable piece 32).

That is, the piece 22 has a flat surface so that the upper and lower surfaces 23, 23 are joined to the inner surfaces of the outward flanges 13, 13A.
The tightening torque of the bolt 14 is limited by the contact of 13A. Further, the rear surface is formed into an arcuate surface 24 so as to abut against the outer periphery of the polydentate tube 4 and tightened, and the side surface thereof is joined to the pair of inclined cam surfaces 19, 19, for example, a 45 ° angled cam. It is formed on the surfaces 25, 25.

Here, since the inner surfaces of the pair of upper and lower outward flange portions 13 and 13A are joined and held, the piece 22 is provided for bringing the outward flange portions 13 and 13A close to each other. Although the tightening torque of the bolt 14 is temporarily limited, the C-shaped tightening member 11 is made of SUS sheet metal, the piece 22 is made of resin, and a driver for tightening the bolt 14 is used.
Is an auto driver (rotated by a motor). In particular, since the polybuten tube 4 has a large amount of resin deformation, excessive or insufficient tightening is likely to occur.
Even if excessive tightening occurs, the above-mentioned tightening torque limitation alone cannot completely prevent this.Although the anti-seizing agent that forms the protective film is applied to the bolt surface, the seizure phenomenon due to excessive tightening is It was found to still be sporadic.

Therefore, in FIG. 1 and FIG.
A pair of breakable pieces 32, 32 are integrally provided on both sides of the front surface opposite to the inclined cam surfaces 19 provided on both side surfaces of the folding claw 18, respectively. 21 can be contacted. A vertical groove 33 is formed between the pair of longitudinally strip-shaped breakable pieces 32, 32 so that the breakable pieces 32 can be broken well.

2 and 3, a pair of breakable pieces 32A, 32A are integrally provided on the upper and lower front surfaces of the piece 22, and the breakable piece 32A is attached to the base of the bending claw 18, ie, the base. The outer flange portion 13 can be brought into contact with the outer edge.

A horizontal groove 33A is formed between the pair of upper and lower laterally strip-shaped breakable pieces 32A, 32A so that the breakable piece 32A can be broken well.

Therefore, when the bolt 14 is screwed into the nut 16 and tightened, the piece 22 in FIG. 3 changes from the state shown in FIG. 2A to the state shown in FIG. That is, when the bolt 14 is tightened, as shown by the arrow, a pair of outward flange portions 1 are formed.
Since the 3 and 13A approach each other, the inclined cam surfaces 19 and 19 of the bending claws 18 press the angled cam surfaces 25 of the piece 22 to guide and move the piece 22 inward (the fastening member body). By moving to the 17 side, it is also simply referred to as inner movement.

On the other hand, at this time, the upper and lower outward flange portions 13 and 13A approach each other, so that the bent piece 18 is formed.
, Ie, the outer edge of the outward flange portion 13 is guided forward, and immediately before the leading edges 20, 20 of the upper and lower opposed bent pieces 18, 18, come into contact with each other, the piece 22 is broken. Pressing the possible piece 32A, it is extruded and broken as shown in FIG. 2 (B). When such a phenomenon is visually observed, the bolt 1
4 may be stopped.

Therefore, C in the C-shaped tightening member 11
The polydent tube 4 in the opening 12 is a piece 2
2, the polybuten tube 4 is uniformly tightened in accordance with the reduced diameter of the tightening member body 17.

When the bolts 14 are screwed together for tightening, the upper and lower surfaces 23, 23 of the piece 22 and the leading edges 20, 20 of the opposing bent claws 18 abut against each other to limit the tightening torque of the bolt 14. At the same time, the limitation of the tightening torque can be visually observed by the breakage of the breakable piece 32A. Therefore, the outward flange portions 13 and 13A are not tightened until they are deformed. As a result, seizure of the bolt 14 and the nut 16 can be prevented. It should be noted that the thickness of the piece 22 should be equal to the length of the two claws of the pair of bent claws 18, 18.
It is slightly smaller.

The C-shaped tightening member 11 does not insert and tighten the C-shaped collar 26 similar to the C-shaped collar 58 shown in FIG. 6 (see FIG. 1). -But A is tightened directly.
Cover at 26. Note that the C-shaped collar 26 may not be used.

The U-shaped notch 29 of the piece 22 may be pressed by a cam (not shown) provided on the bolt 14 to press the piece 22.

In the figure, 27 is an O-ring (FIG. 1), 2
Reference numeral 8 denotes a washer (FIG. 1), and reference numeral 29 denotes a U-shaped notch (FIG. 3A), which is an insertion hole for the bolt 14. 30 is a U-shaped notch (FIG. 5)
In (A)), correction of the tightening of the bolt 14 and the piece 2
2 has good pressing. Reference numeral 31 denotes a spot melting portion of the nut 16 (FIG. 2).

[0044]

According to the present invention, the soft tube located at the C-shaped opening formed by the outward flange portion of the C-shaped tightening member is tightened by the piece, so that the C-shaped tightening member is used. Tightening becomes uniform, wrinkles of the soft tube are prevented, sealability is improved, and an inexpensive C-shaped tightening member can be provided.

Of course, if the C-shaped tightening member is made of sheet metal, it can be inexpensively processed and satisfactorily hold the piece.

In particular, the tightening operation by the C-shaped tightening member of the present invention is more visible than the tightening by externally fitting a nut (for example, see Japanese Patent Application Laid-Open No. 6-346994), and
Although there is a possibility of repetition such as redoing, etc., while taking advantage of such features, the tightening torque is limited by the piece piece, so that there is no excessive tightening on the C-shaped tightening member, and the work is further simplified. And improve the reliability of tightening.

Further, since the breakable piece is provided at the outer end of the piece, the tightening torque of the bolt and nut can be visually observed accurately, and in combination with the tightening torque limit, the polydent tube can be used. It is possible to prevent not only insufficient sealing due to insufficient tightening but also seizure of the bolt and nut due to excessive tightening in a soft tube such as described above.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an embodiment of the present invention.

FIG. 2 is an enlarged detailed view of a main part of a modification of FIG. 1;

FIG. 3 is an enlarged detailed view of a main part of FIG. 2;

FIG. 4 is another embodiment of FIG.

FIG. 5 is a detailed view of another main part of FIG. 2;

FIG. 6 is a partially cutaway side view of a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Fitting, 2 ... Fitting main body, 3 ... Mounting screw part, 4 ...
Polytube tube, 5: tube insertion portion, 11: C-shaped tightening member, 12: C-shaped opening, 13, 13A: outward flange portion, 14: bolt, 18: bending claw, 22: piece shape Piece, 32, 32A ... breakable piece

Claims (1)

(57) [Claims] 1. A metal joint main body integrally formed with a tube insertion portion, and a soft tube externally fitted to the tube insertion portion are tightened, and when tightened, they are opposed to each other and close to each other. A C-shaped tightening member having a pair of outwardly extending flanges extending therefrom, a bolt insertion hole being drilled in one of the outwardly flanged portions, and a nut provided in the other outwardly flanged portion. A metal pipe joint for a soft tube, comprising: a bolt which is inserted into the nut and is screwed to the nut so that these outward flange portions are brought close to each other, and tightened by the pair of outward flange portions. At the time of tightening, an inwardly movable piece that clamps the flexible tube in the C-shaped opening of the C-shaped tightening member is clamped, and the outward flange is fastened to the outer end of the piece. By providing a breakable piece that breaks occasionally, , Soft Ju characterized by the restriction of the torque Bolt - Bed metal pipe joint.