JP2000186792A - Single operation joint for flexible tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To combine slip-off preventing performance of a joint and a flexible tube sealing performance, and fire resistance of a sealing part by joining the joint and the tube to each other in a single operation only by inserting the flexible tube. SOLUTION: A taper surface 37 is formed on the inner periphery of a pressing ring 25, and an annular retainer 44 constituted of a press molded article is arranged on the inner peripheral side of the taper surface 37. In the retainer 44, a projecting part 46 is elastically extended by an angled part 4 of a corrugated pipe 2 when a flexible tube 1 is inserted, and the projecting part 46 is engaged with a root part 5 of the corrugated pipe 2 by the passage of the angled part 4. A sealing material 21 in a cylindrical main body 11 can seal the angled part 4 of the corrugated pipe 2 and at least partially formed of a fire resistant part 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-touch joint for a flexible tube, and more particularly to a one-touch joint for a flexible tube formed of a corrugated tube used for gas piping and the like.

[0002]

2. Description of the Related Art As a conventional flexible tube joint of this type, a metal tubular main body having an abutment surface therein and a flexible tube from which a coating of several peaks of a corrugate tube has been removed are inserted. In this state, the distal end is engaged with a metal pressing ring screwed into the inside of the tubular main body, and the valley on the outer periphery of the corrugated tube of the flexible tube attached to the distal end of the pressing ring and inserted through the pressing ring. One having a retainer having a metal projection that can be fitted is disclosed in, for example, Japanese Patent Application Laid-Open No. 8-159350.

In such a joint for a flexible tube, the flexible tube is inserted into the push ring in a state where the push ring is temporarily loosely screwed into the cylindrical main body, so that the crest at the tip of the flexible tube becomes the retainer. The protruding part is pushed out and passes through the position of this protruding part. With this, in a state where the tip of the corrugate pipe projects from the tip of the retainer by a predetermined amount, the protrusion of the retainer engages with the valley of the corrugate pipe. Thereafter, by further screwing the pressing ring, the corrugate projecting from the tip of the retainer. The distal end portion of the tube can be crushed and squeezed in a close state between the projection of the retainer and the contact surface of the tubular main body.

As a result, the flexible tube is connected to the joint in a sealed state, and the corrugated tube is sealed by crushing the corrugated tube between the metal portions, so that the sealed portion has fire resistance. And between the abutment surface of the cylindrical body and
It also has the effect of preventing the corrugated tube from slipping out.

[0005]

However, Japanese Patent Application Laid-open No.
In the joint described in Japanese Unexamined Patent Publication No. 159350, it is necessary to further screw the pressing ring after the insertion of the flexible tube as described above, and furthermore, it is necessary to crush the distal end portion of the corrugated tube by the screwing. There is a problem that requires power.

Accordingly, the present invention solves such a problem, so that the joint and the tube can be joined with one touch only by inserting the flexible tube into the joint, and the joint and the flexible tube can be prevented from coming off.
An object of the present invention is to make it possible to have both sealability and fire resistance of a seal portion.

[0007]

According to the present invention, a joint for a flexible tube constituted by a corrugated tube is screwed into a cylindrical main body and a distal end portion is screwed into the cylindrical main body. The flexible tube includes a corrugated tube, through which a corrugated tube can be inserted from the end of the pressing ring toward the inside of the pressing ring and the cylindrical main body, and the inner periphery of the pressing ring includes a tip side of the pressing ring. A tapered surface that increases in diameter is formed, and an annular retainer is arranged on the inner peripheral side of the tapered surface of the pressing ring. This retainer is formed of a press-formed product and has an outer periphery that can contact the tapered surface of the pressing ring. Portion and a radially inwardly projecting projection, and can be expanded and reduced in diameter, and the retainer is configured such that when the flexible tube is inserted, the projection is formed by a peak on the outer periphery of the corrugated tube. By being expanded, the passage of this peak is allowed, and by passing this peak, the protrusion can be deformed so as to engage with the valley on the outer periphery of the corrugate tube, and the inside of the cylindrical main body is formed. An annular sealing material is provided, and the annular sealing material is capable of sealing the outer periphery of the peak portion of the corrugated pipe by its inner peripheral surface, and at least a part thereof is formed of a material having fire resistance. It is like that.

With such a configuration, the flexible tube and the joint are sealed by a one-touch operation of merely inserting the flexible tube into the joint without any other operation such as screwing of the member. In this state, they are securely joined to each other.

[0009] When a pull-out force from the joint acts on the flexible tube, the outer peripheral portion of the retainer is pressed against the tapered surface of the inner circumference of the pressing ring, and the reaction force causes the protrusion to project radially inward to the protrusion. A force acts, and this force acts on the retainer to reduce the diameter, so that the protrusion is strongly engaged with the valley of the corrugated tube, so that the protrusion is prevented.

Since the retainer is formed by a press-formed product, it can be manufactured at low cost.

The corrugated pipe and the joint are sealed with a seal material. Since at least a part of the seal material is formed of a material having fire resistance, the seal material has the fire resistance even when a fire or the like occurs. The parts formed of the material do not burn away, so that the required sealing properties are maintained.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 1 denotes a flexible tube, which is a thin stainless steel corrugated tube 2;
The corrugated tube 2 is made up of a resin-made tubular covering 3 covering the outer periphery of the corrugated tube 2. In the corrugated tube 2, reference numeral 4 denotes a peak, and 5 denotes a valley. The flexible tube 1 is connected to the joint in a state where the coating 3 has been removed at several peaks of the corrugated tube 2.

In this joint, reference numeral 11 denotes a cylindrical main body, which is formed of metal such as brass and has an external thread 1 at one end thereof.
2 is formed so that it can be connected to a connected object such as a gas pipe. A hexagonal portion 13 is used for screwing the outer thread portion 12.
14 is an end surface on the other end side.

An inner thread 15, an inner peripheral surface 16, an annular seal material housing 17, a corrugate tube housing 18, and an inner thread 15 are arranged on the inner circumference at the other end of the cylindrical body 11 in this order from the opening side. Is provided. The corrugated tube accommodating portion 18 is formed to have a smaller diameter than the sealing material accommodating portion 17 and is configured to be able to accommodate the crest 4 at the tip of the corrugated tube 2. An annular rubber sealing material 21 is loosely press-fitted in the sealing material housing 17.

Reference numeral 25 denotes a pressing wheel, which is formed in a cylindrical shape from a metal such as brass, and has a cylindrical main body 11 at one end thereof.
Has an outer threaded portion 26 which can be screwed into the inner threaded portion 15. A circumferential outer peripheral surface 27 is formed on the outer periphery on the other end side of the pressing wheel 25. The outer peripheral surface 27 is formed to have a larger diameter than the outer thread portion 26, and thus an end surface 28 facing the end surface 14 of the tubular main body 11 is formed. An annular packing 31 is attached to a portion of the pressing wheel 25 on the base end side of the end face 28. The packing 31 is compressed between the end face 14 and the end face 28 when the press ring 25 is screwed into the tubular main body 11.

A hole 33 through which the flexible tube 1 is inserted is formed in the pressing wheel 25 in a penetrating state. A packing 34 is accommodated in the inner periphery of the hole 33 on the other end side of the press wheel 25. In the hole 33, a cover housing 36 is formed on one end side of the pressing wheel 25 with respect to the packing 34. Pressing wheel 2 in hole 33
A tapered surface 37 whose diameter increases toward one end of the pressing wheel 25 is formed on the inner periphery of one end of the pressing wheel 5. The tapered surface 37 is formed to have substantially the same diameter as the packing housing portion 17 of the cylindrical body 11 at one end side, that is, the opening side, of the pressing ring 25, while the coating body housing portion is formed at the other end side, that is, the back side of the pressing ring 25. The diameter is smaller than 36. Therefore, a radial step 38 is formed at the boundary between the cover housing 36 and the tapered surface 37.

As shown in FIG. 1, the pressing wheel 25 is connected to the cylindrical main body 11.
Surface of the pressing wheel 25 in a state of being screwed into
An annular retainer 44 is arranged on the inner peripheral side of the.
As shown in FIGS. 1 to 3, the retainer 44 is formed by an inexpensive press-formed product using a metal material such as stainless steel.

More specifically, the retainer 44 has an outer peripheral portion 45 having a cross section of an "H" shape, which is inclined along the tapered surface 37 of the pressing ring, and a projection projecting toward the inner peripheral side. 46, and the projection 46 is formed in an inclined shape that protrudes toward the distal end side toward the inner peripheral side. In the retainer 44, cuts 47 in the axial direction from the protrusion 46 to the outer peripheral portion 45 are formed at a plurality of positions along the circumferential direction. For this reason, the protrusion 46 is configured to be divided into a plurality of pieces along the circumferential direction. In the retainer 44, cuts 48 in the axial direction from the outer peripheral portion 45 to the protruding portion 46 are formed at a plurality of positions along the circumferential direction avoiding the cuts 47. Thereby, the retainer 4
Reference numeral 4 denotes a configuration in which the constituent materials are arranged in a zigzag fashion along the circumferential direction, so that the projection 46 can easily and elastically expand and contract in diameter. The protrusion 46
It is also possible to provide a configuration in which only the notch 47 is provided to the outer peripheral portion 45 and the notch 48 on the opposite side is not provided.

As shown in FIG. 1 and FIG.
Reference numeral 1 denotes a cylindrical body in which a ring-shaped refractory part 22 and a general rubber part 23 are integrated in the axial direction, and is arranged such that the refractory part 22 is located on the back side of the cylindrical main body 11. I have. The refractory part 22 and the general rubber part 23 are formed so that the inner diameter and the outer diameter are equal, and are formed such that the dimensions in the axial direction are substantially equal. The refractory portion 22 has a configuration in which, for example, thermally expandable graphite is mixed in nitrile rubber. The general rubber portion 23 is formed of, for example, nitrile rubber.

In such a structure, when forming a joint, first, the sealing material 2
Put 1 in. The packing 31 and the packing 34 are attached to the pressing wheel 25 in advance. Then, with the retainer 44 accommodated in the inner peripheral side of the tapered surface 37 of the pressing wheel 25, the pressing wheel 25 is screwed into the tubular main body 11 and fixed. Then, the state shown in FIG. 5 is obtained. At this time, the packing 31 is compressed by the end surface 28 of the press wheel 25 approaching the end surface 14 of the cylindrical main body 11.

The joint and the flexible tube 1 in this state
5 was cut off from the state shown in FIG. 5 at the valley 5 of the corrugated tube 2 as shown in FIG. 1 and the coating 3 was removed at several peaks at the tip of the corrugated tube 2. The flexible tube 1 in the state is inserted into the hole 33 from the end of the pressing wheel 25. Then, as shown in FIG.
The peak 4 of the tip of the corrugated tube 2 is the protrusion 4 of the retainer 44.
In step 6, the retainer 44 is moved in a direction approaching the seal member 21. Then, the outer peripheral portion 45 of the retainer 44
Moves away from the tapered surface 37 of the press wheel 25.

In this state, the flexible tube 1
Is inserted, the retainer 44 hits the end face of the sealing material 21, and this time, as shown in FIG.
Acts on the inclined protrusion 46 of the retainer 44 to push and expand the retainer 44 to pass through the inner periphery of the protrusion 46. At this time, since a plurality of cuts 47 and 48 are formed in the retainer 44 in the circumferential direction as described above, the push and spread of the retainer 44 can be easily performed.

Similarly, when several peaks of the corrugated pipe 2 pass through the protrusion 46 of the retainer 44, the several peaks of the corrugated pipe 2 enter the inside of the sealing material 21 as shown in FIG. In addition, the highest peak 4 of the corrugated tube 2 passes through the position of the sealing material 21 and enters the housing 18. At this time, the sealing member 21 has a function to seal the inner peripheral surface of the sealing member 21 to the corrugated tube 2 with the inner peripheral surface thereof being in close contact with the peak portion 4 of the corrugated tube 2. FIG. 1 shows the state at this time. At this time, the retainer 44
Has returned to its original reduced diameter state due to elasticity.
Are engaged in one valley 5 of the corrugated tube 2.

In the state shown in FIG.
Of the cover 3 is stuck in the accommodating portion 36 and approaches the step portion 38. Further, in this state, the packing 34 of the pressing wheel 25 seals the outer periphery of the covering 3 of the flexible tube 1. The packings 31 and 34 are mainly used to prevent water and the like from entering the inside of the joint.

In this way, the flexible tube 1 and the joint are sealed in a one-touch operation only by inserting the flexible tube 1 into the joint without any other operation such as screwing of the members. They can be securely joined to each other.

When a force is applied to the flexible tube 1 from the joint from the state shown in FIG.
The outer peripheral portion 45 of the retainer 44 in which the protrusion 46 is engaged with one valley portion 5 of the corrugated pipe 2 is formed on the tapered surface 3 of the pressing ring 25.
7, the retainer 44 receives a radially inward reaction force from the pressing wheel 25. Then, the projection 46 inclined in the direction opposite to the exit direction presses the outer circumference of one valley 5 of the corrugated pipe 2 over the entire circumference, so that the engagement between the retainer 44 and the corrugated pipe 2 is ensured. This prevents the flexible tube 1 from coming out of the joint.

That is, since the projection 46 is engaged only with one valley 5, when the diameter of the retainer 44 is reduced by the action of the tapered surface 37 of the pressing wheel 25, this projection 46 is used.
The force of engagement with the valley 5 can be concentrated at the tip of the ridge. Thereby, even when a large detaching force is applied, the detachment of the flexible tube 1 from the joint can be reliably prevented.

If the joint is exposed to a high temperature due to a fire or the like after the joining is completed, even if the general rubber portion 23 of the sealing material 21 is burned out, the heat-expandable graphite expands in the refractory portion 22 on the back side. Thus, the sealing property with the corrugate tube 2 is maintained. Therefore, required fire resistance is ensured. When exposed to high temperatures due to a fire or the like, the refractory portion 22 on the back side becomes brittle. The tube 2 does not sway in the radial direction, and therefore, it is possible to prevent the brittle refractory portion 22 from being damaged by the sway of the corrugated tube 2 and reducing the sealing performance.

FIG. 8 shows another embodiment of the present invention. Here, over the inside of the cylindrical main body 11 and the pressing wheel 25,
A collar 40 formed of a metal such as brass or a resin having a required strength is provided.

With such a configuration, when the retainer 44 presses down the thin corrugated tube 2 by the force of pulling out from the joint on the flexible tube 1, the collar 40 backs up the corrugated tube 2. Thus, the deformation of the recorgate tube 2 due to the force of the retainer 44 and the occurrence of detachment from the joint due to the deformation are reliably prevented.

[0031]

As described above, according to the present invention, the flexible tube can be connected to the joint by one-touch operation only by inserting the flexible tube into the joint without any other operation such as screwing of members. Can be securely joined to each other in a sealed state. Further, since the outer peripheral portion of the retainer is pressed against the tapered surface of the inner periphery of the pressing wheel, the protruding portion is strongly engaged with the valley portion of the corrugate tube by the reaction force, so that the flexible tube can be prevented from coming out of the joint. Since the retainer is formed by a press-formed product, it can be manufactured at low cost. Furthermore, since the corrugated pipe and the joint are sealed by a sealing material, and at least a part of the sealing material is formed of a fire-resistant material, even in the event of a fire or the like, the fire-resistant material can be used. The formed part does not burn out, and thus the required sealing performance can be maintained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a one-touch joint for a flexible tube according to an embodiment of the present invention.

FIG. 2 is a diagram showing a retainer in FIG. 1 in detail.

FIG. 3 is a perspective view of the retainer.

FIG. 4 is a perspective view of a sealing material in FIG. 1;

FIG. 5 is a sectional view showing a state before a flexible tube is inserted into the joint of FIG. 1;

FIG. 6 is an enlarged sectional view of a main part showing a next stage of FIG. 5;

FIG. 7 is an enlarged sectional view of a main part showing a next stage of FIG. 6;

FIG. 8 is a cross-sectional view illustrating a configuration of a one-touch joint for a flexible tube according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flexible tube 2 Corrugated pipe 4 Crest part 5 Valley part 11 Cylindrical main body 21 Seal material 25 Pressing ring 37 Tapered surface 44 Retainer 45 Outer peripheral part 46 Projection 47 Notch

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Mikio Nakaoka 2-10-16 Minamikagaya, Suminoe-ku, Osaka-shi, Osaka Inside Shinwa Sangyo Co., Ltd. No.10-16 Shinwa Sangyo Co., Ltd. F-term (reference) 3H017 CA03 3J106 AA02 AA04 AB09 BA10 BB01 BC03 BD01 BE13 BE21 BE29 CA16 DA02

Claims (6)

[Claims] 1. A joint for a flexible tube comprising a corrugated tube, comprising: a tubular main body; and a pressing ring having a tip portion screwed into the inside of the tubular main body. Is inserted from the end of the pressing ring toward the inside of the pressing ring and the cylindrical body, and a tapered surface is formed on the inner periphery of the pressing ring, the diameter of which increases toward the tip end side of the pressing ring, An annular retainer is arranged on the inner peripheral side of the tapered surface of the press ring, and this retainer is formed by a press-formed product,
It has an outer peripheral portion capable of contacting the tapered surface of the pressing ring, and a radially inwardly projecting projection, and is capable of expanding and contracting diameter. When the flexible tube is inserted, the corrugate The projection is pushed and spread by the ridge on the outer circumference of the pipe to allow passage of this ridge, and by passing through this ridge, the projection is deformed to engage with the valley on the outer circumference of the corrugated pipe. An annular sealing material is provided inside the cylindrical main body, and the annular sealing material is capable of sealing the outer periphery of the corrugated pipe ridge by its inner peripheral surface, and at least a part thereof is fire resistant. A one-touch joint for a flexible tube, characterized by being formed of a material having a property. 2. An outer peripheral portion of the retainer is formed in an oblique direction along a tapered surface of the pressing ring, and a protrusion of the retainer is formed in an inclined shape that protrudes toward the distal end toward the inner peripheral side. The one-touch joint for a flexible tube according to claim 1. 3. The one-touch joint for a flexible tube according to claim 1, wherein the retainer has a cut in an axial direction from the protruding portion side to the outer peripheral surface side. 4. A cylindrical body, and a push ring having a tip portion screwed into the inside of the tubular body, and a corrugate tube constituting a flexible tube is provided at an end of the push ring from an end of the push ring.
It can be inserted toward the inside of this push wheel and the cylindrical body,
A retainer used for a joint having a tapered surface on the inner periphery of the press ring, the diameter of which is increased toward the distal end of the press ring, and an annular press forming process disposed on the inner peripheral side of the taper surface of the press ring. It has an outer peripheral portion that can be in contact with the tapered surface of the pressing wheel, and a projection that projects inward in the radial direction, and can be expanded and reduced in diameter, when the flexible tube is inserted. The projecting portion is allowed to pass through the peak by being expanded by the peak on the outer periphery of the corrugated pipe, and the projection is engaged with the trough on the outer periphery of the corrugated pipe by passing the peak. A retainer for a one-touch joint for a flexible tube, wherein the retainer is adapted to be deformable. 5. An outer peripheral portion is formed in an oblique direction along a tapered surface of a pressing wheel, and the projection is formed in an inclined shape that protrudes toward a front end side toward an inner peripheral side. A retainer for the described one-touch fitting for a flexible tube. 6. The retainer for a one-touch joint for a flexible tube according to claim 4, wherein the retainer has a cut in the axial direction from the projecting portion side to the outer peripheral surface side.