JPH07301379A - Flexible pipe joint - Google Patents

Abstract

PURPOSE:To provide a flexible pipe joint capable of preventing the flexible pipe from being elongated by squeezing sufficiently a blade to be sheathed in fixing the flexible pipe and holding a mechanical binding force and high sealing property between the flexible pipe and a connecting fitting. CONSTITUTION:A flexible pipe joint has a connecting fitting 16 and a flexible pipe 12 having the straight end part sheathed by the connecting fitting and is fitted by a first fixing ring 22 to fix these connecting fitting and flexible pipe. Then, the flexible pipe and the outer surface of a first fixing ring are covered and sheathed with a blade 30 having the extended end, and a second fixing ring 32 externally fitted on the blade end 30a to fix the blade end to the connecting fitting is provided. The blade is sufficiently sequeezed to be fixed after fitting the flexible pipe, and further, a mechanical binding force, sealing property and the like are improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint for piping for supplying a pressure fluid, and more particularly to a flexible pipe joint.

[0002]

2. Description of the Related Art Conventionally, flexible pipe joints have been widely used for pipes for supplying water such as tap water because of their displacement absorbability and high flexibility in the pipe direction. Since the conventional flexible joint is easy to process, the end straight pipe portion of the flexible pipe is inserted into the inner diameter side of the connection fitting and joined by using an O-ring or a tube expander method. In this case, joining is performed by bulging from the inner surface of the flexible pipe. If the connecting fitting has a right cylindrical shape, it can be carried out without any trouble, but if it has an elbow shape, joining becomes difficult. As a flexible pipe joint that can be used for elbow-shaped connecting fittings in recent years, the one shown in Figs. 3 and 4 has been proposed. This pipe joint is a flexible pipe (bellows pipe) 12 in which pleats (corrugations) are continuously formed. An O-ring mounted on the outer circumference of the connection fitting corresponding to the overlapped portion by covering the blade 30 and inserting a connection fitting into one end of the flexible pipe, and fitting the ring-shaped metal fitting at the overlapping portion between the flexible tube and the blade. It has a structure in which a metal fitting is clamped and fixed from the outside so that the flexible tube and the flexible tube come into close contact with each other.

[0003]

By the way, according to this conventional flexible pipe joint, since the overlapping portion of the flexible pipe and the blade is further caulked and fixed from the outer surface side with the metal fitting, the flexible pipe and the blade with respect to the connecting fitting are fixed. Therefore, it is impossible to remove the slack of the blade by applying sufficient ironing to the blade to be sheathed in the flexible tube, and if pressure is applied to the inside of the pipe joint during use, the flexible tube will There was a problem that it stretched (when the pressure was applied to the inside of the flexible tube without restraint of the blade, the folds stretched and returned to the cylinder), abnormal deformation occurred, and unstable movement caused a damage accident. Further, regarding the connection between the flexible pipe and the connecting metal fitting, a metal fitting whose diameter slightly expands from the flexible pipe side to the other end is formed on the blade at the overlapping portion of the flexible pipe and the blade which are sheathed in the connecting metal fitting. It is difficult to firmly fix the flexible pipe and the blade to the connecting metal fittings only by fixing them by sheathing and caulking.Therefore, when the flexible pipe joint is used to absorb the misalignment of the actual pipe, If one end is fixed and the other end is bent, a large tensile force is generated in the axial direction, and as a result, the flexible pipe may be detached from the connection fitting, causing a great trouble.

The present invention has been made in view of the above-mentioned problems of the prior art, and one of the objects thereof is to fix the flexible pipe and the connecting fitting, and then to enclose the blade including both of them,
By fixing the ends, it is possible to give the blade sufficient ironing to prevent the flexible pipe from extending, maintain the original sufficient flexibility of the pipe joint, and prevent damage accidents and other derivative accidents. It is to provide a pipe joint. Another purpose is to form a male / female fitting part or a protruding part in the connecting fitting and the fixing ring, and to interpose a flexible pipe to join the fixing ring and the connecting fitting with a strong mechanical coupling force, and at the same time, to achieve a high seal. It is to provide a flexible pipe joint that can secure the property.

[0005]

In order to achieve the above object, the present invention provides a cylindrical connecting fitting 16 and a straight pipe portion 14 at an end of the connecting fitting 16 so as to continuously fold the folds. And the flexible pipe 12 formed by
6, the first fixing ring 22 is fitted from the outside of the exterior portion 18 of the flexible pipe 12 to the connecting fittings 16
And the flexible pipe 12 are fixed, the connection fitting 16 and the flexible pipe 12 are fixed by the first fixing ring 22, and then the outer surfaces of the flexible pipe 12 and the first fixing ring 22 are covered. An end portion 30a extending in a direction away from the blade 30 to cover the blade 30 and fitted from the outside of the blade end portion 30a,
Flexible pipe joint 10 comprising a second fixing ring 32 for fixing the blade end 30a to the connecting fitting 16.
Composed of.

[0006] One or a plurality of recessed grooves 20 are formed on the outer peripheral surface of the connection fitting 16 at a position corresponding to the exterior portion 18 of the flexible pipe 12, and further, on the inner peripheral surface of the first fixing ring 22. It is also possible to form a projecting peripheral portion 24 that fits or projects into the concave groove 20.

The concave groove 20 may be filled with an adhesive 26, and the projecting peripheral portion 24 may be fitted into the concave groove 20 in this state.

Further, the first fixing ring 22 and the second fixing ring 32 are mounted with a required gap, and at least the first fixing ring 22 is attached to the outer periphery of the connecting fitting 16 at a portion corresponding to the gap. The end portion 22a may be provided with a ridge 28 having a step portion 28a that is in close contact with each other.

[0009]

In the flexible pipe joint according to the first aspect of the present invention, the flexible pipe and the connecting fitting are fixed by the first fixing ring, and then the blade is packaged so as to include both the flexible pipe and the first fixing ring, and thereafter, Since the end of the blade is fixed to the blade, the blade is sufficiently ironed, and the surface of the flexible pipe is sufficiently blended with the blade, and after confirming this, finally the end of the blade is used as a connection fitting. Can be fixed.

According to the flexible pipe joint of the second aspect, one or more recessed grooves are formed on the outer periphery of the connection fitting,
Further, by forming a projecting peripheral portion on the inner peripheral surface of the first fixing ring at a position corresponding to these, the both are joined in the male and female fitting state, so that the caulking joining force of the first fixing ring as well as these male and female fitting The joint force acts by joining, and the flexible pipe is connected and joined to the fitting with a strong mechanical joining force.

In the flexible pipe joint of claim 3, since the concave groove is filled with the adhesive, the holding portion of the adhesive is determined, and the connection fitting and the flexible pipe are securely adhered to each other to enhance the mechanical joining therebetween. The sealability can be improved.

Further, according to the flexible pipe joint of the fourth aspect, when the flexible pipe and the first fixing ring and the like are mounted on the ridge so as to abut against the step portion, the mounting workability is improved. Will be good.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the accompanying drawings. The same members as those in the conventional flexible pipe joint are designated by the same reference numerals. FIG. 1 and FIG. 2 are a partially omitted sectional explanatory view of a flexible pipe joint 10 according to an embodiment of the present invention and an enlarged sectional explanatory view of its main part. A straight tubular portion 14 having a straight tubular shape is formed at one end of a flexible tube (flexible tube) 12, and a cylindrical connecting fitting 16 is connected to the straight tubular portion 14.

The flexible tube 12 has a hollow cylindrical structure, the surface of which is formed into a corrugated corrugated cross section by subjecting a straight tube to a crimping process, and the inside and outside thereof are kept watertight. The straight pipe portion 14 may be formed by a method in which only a required portion is secondarily processed into a straight pipe after the continuous pleating is performed, or a portion which is not pleated during pleating (corrugation) formation is left. Is also good.

The connection fitting 16 connected to one end of the flexible tube 12 is formed of a cylindrical sleeve tube made of stainless steel or other metal in the embodiment. Then, one end side of the connection fitting 16 is inserted into one end portion of the flexible pipe 12. That is, one end of the flexible pipe 12 is exteriorly mounted on the end of the connection fitting 16, and this portion forms the exterior portion 18.

In this embodiment, two recessed grooves 20 are continuously provided in the circumferential direction on the outer periphery of the connecting fitting 16 corresponding to the exterior portion 18 of the flexible tube 12 at some intervals in the axial direction. . This groove shape may be arbitrary,
In the embodiment, the corner portion is a rectangular groove having a right angle, but it may be formed, for example, in an inverted trapezoidal shape so as to be enlarged toward the opening side of the cross section, or may have another shape.

On the other hand, the first fixing ring 22 is fitted from the outside of the exterior portion 18 of the connection fitting 16 in a state where one end of the flexible tube 12 is exteriorized. Also,
On the inner peripheral side of the first fixing ring 22, the connection fitting 1
Two projecting circumferential portions 24 that continuously project in the circumferential direction are provided at positions corresponding to the concave grooves 20 of 6. The first fixing ring is a metal ring, and is crimped, pressed, and
The flexible tube 12 is joined at the exterior portion 18 of the connection fitting 16 by caulking or another method.

In the embodiment, the adhesive 26 is filled in the concave groove 20 of the connection fitting 16. By forming the groove 20, the adhesive 26 is held in place therein. As the adhesive, it is preferable to use a metal adhesive or the like which has a strong bonding force and has a good sealing property.

As a result, when the first fixing ring 22 is crimped so that the projecting peripheral portion 24 of the first fixing ring 22 fits or projects into the concave groove 20 of the connecting fitting 16, the flexible pipe 12 and the connecting fitting 16 are separated from each other. Firstly, the caulking force by the first fixing ring 22 secures the mechanical joining, and
The male and female fitting of the concave groove 20 and the projecting peripheral portion 24 secures the joining force between the two, and in addition, the adhesive agent holds the almost complete mechanical joining force. Further, since they are connected by such a strong mechanical joining force and at the same time, the perfect sealing property is maintained, stable piping work can be performed using this kind of flexible pipe joint. That is, somewhat rough installation work can be performed, work time can be shortened, and centering work of the pipes to be connected can be surely performed.

In the embodiment, two pairs of each of the groove 20 and the projecting portion 24 are formed, but one pair may be formed.
Also, two or more may be provided. The more it is provided, the better the mechanical joining force and the sealing property.

As described above, the mechanical joining force is greatly improved by fitting the concave groove 20 and the projecting peripheral portion 24 together with the concave groove 20.
By filling the inside with the adhesive agent 26, the pressure contact force between the O-ring embedded in the connection fitting and the metal fitting for caulking is simply higher than that of forming watertightness between the flexible pipe and the connection fitting, and It becomes possible to secure a perfect sealing property.

The connection fitting 16 is located in a direction away from the flexible tube 12 with respect to the groove 20 of the connection fitting 16.
A ridge 28 is continuously formed on the outer circumference of the ridge 28 in the circumferential direction. The protrusion 28 is provided with a step portion 28a so that the end portion 22a of the first fixing ring substantially abuts. The stepped portion of the ridge 28 is located at a position where the concave groove 20 and the protruding peripheral portion 24 are fitted to each other and the straight pipe portion 14 and the first portion.
The ends of the fixing ring 22 are formed to abut against each other. As a result, the flexible pipe 12 is connected to the connecting fitting 16
On the other hand, at the time of exterior mounting, the straight pipe portion 14 is fitted into the step portion 28a until it abuts, and the end 22a of the first fixing ring 22 is also abutted and abutted against the step portion, which is simple. Positioning for joining can be performed.

After the connection fitting 16 and the flexible tube 12 are fixed by the first fixing ring 22, the flexible tube 12 and the first fixing ring 22 are covered, and the end portion extends in the direction away from the flexible tube 12. The blade 30 is provided.

In the preferred embodiment, this blade 30 is of hollow knit construction made of stainless steel. It is known that the blade is made of a tape-shaped stainless steel plate, or a braid unit in which wire strands are arranged and knitted into a hollow cylindrical shape. The flexible tube 12 inside has elasticity and deformability. On the other hand, when the pressure is applied from the inside, the concave and convex portions are protected from extending, and a metal blade having an arbitrary configuration may be used.

The outer surface of the first fixing ring 22 is further extended to the end portion 30a of the blade 30, and the second fixing ring 32 is further provided.
Is fitted from the outside, and is fitted into the adjacent concave peripheral portion 34 of the ridge 28 by crimping, pressure welding, or another method, and is caulked and fixed. This second fixing ring is also a metal ring made of stainless steel or steel. At this time, since the flexible tube 12 is already firmly joined to the connecting fitting 16 as described above, the second fixing ring 32 can be crimped and fixed while the blade 30 is sufficiently ironed. Therefore, the blade 30 can be closely attached to the flexible pipe 12, and the flexible pipe joint 1 can be mounted, for example, by the pressure of the liquid.
It is possible to prevent 0 from extending in the axial direction and causing a dimensional change.

As described above, the flexible tube and the connecting fitting are joined by the first fixing ring, and the both are water-tightly joined, and then the blade is externally packaged so as to wrap the flexible tube and the first fixing ring. Since the end portion is fixed by the second fixing ring, mechanical joining property, reliable sealing property, and sufficient ironing of the blade can be achieved simultaneously and completely. Moreover, the number of members is small, the structure is simple, and the cost can be kept low. Furthermore, since there is no welded portion due to external crimping or the like, the connecting work is easy, and there is no deterioration in corrosion resistance due to the influence of heat.

Further, since the end portion 30a of the blade covers the first fixing ring 22 and is fixed at the extended end side thereof, the blade protects the flexible tube 12 as well as the first fixing ring. From this point as well, the joint portion between the flexible pipe and the connection fitting is reinforced.

Further, as compared with the conventional method in which a flexible pipe and a blade are superposed and the portion is swaged at once by a pressure welding ring or the like, after fixing the flexible pipe to the connection fitting, further fixing is performed. Only by fixing the blade to the connecting fitting by means, it is possible to obtain a mechanical joining force higher than in the conventional case.

Incidentally, reference numeral 36 in the drawing denotes a synthetic resin protective film having heat shrinkability and the like, which keeps the waterproofness and the like of these joints and the like. Further, 38 is a cap nut connected to the other end of the connection fitting 16 via a direct connection ring 40, and an internal thread portion 42 is formed on the inner diameter portion thereof, and an expansion pipe and other external thread portions of piping or the like to be connected. Are connected by screwing.

The ridge 28 provided on the outer circumference of the connection fitting in the embodiment is not necessarily provided, and a simple peripheral surface may be fixed to the outer circumference by the first and second fixing rings 22 and 32. Further, the second fixing ring may be fixed by caulking adjacent to the first fixing ring 22 (may be in close contact with each other or may be arranged at a separated position).

The flexible pipe joint according to the present invention is not limited to the configuration of the embodiment described above, and may be arbitrarily modified without departing from the essence of the invention described in the claims. For example, an O-ring may be arranged at a required portion such as a connecting fitting in order to further improve the sealing property.

[0032]

As described above, according to the flexible pipe joint of the first aspect, the cylindrical connecting fitting and the straight fitting at the end of the connecting fitting are exteriorly formed to continuously form the folds. A flexible pipe, and a first fixing ring is fitted from the outside of the outer portion of the flexible pipe with respect to the connection fitting to fix the connection fitting and the flexible pipe, and the connection fitting is connected to the connection fitting by the first fixing ring. After fixing the flexible pipe and the outer surfaces of the flexible pipe and the first fixing ring, the end is extended in a direction away from the flexible pipe to externally cover the blade, and the outside of the blade end. And a second fixing ring for fixing the blade end portion to the connecting fitting, the flexible tube and the connecting fitting are fixed together with the second fixing ring. Is the exterior, by fixing the ends, giving sufficient ironing the blade to prevent the extension of the flexible tube, holds the original sufficient flexibility of the pipe joint,
In addition, it can prevent damage accidents and other derivative accidents,
It is possible to improve the mechanical joining force.

According to a second aspect of the present invention, one or more recessed grooves are formed on the outer peripheral surface of the connecting fitting at a position corresponding to the exterior portion of the flexible pipe, and the inner peripheral surface of the first fixing ring is further formed. Since a projecting peripheral portion that fits into or projects into this groove is formed in the groove, the flexible pipe is interposed by the caulking force of the first fixing ring to mechanically join the first fixing ring, the flexible pipe and the connecting fitting. It is also possible to secure the joint strength between the male and female by fitting the concave groove and the projecting peripheral portion with each other.

Further, according to the third aspect, the concave groove is filled with an adhesive, and in this state, the projecting peripheral portion is fitted into the concave groove. Therefore, the first fixing ring is caulked and fixed. At the same time, while maintaining the mechanical jointability by male and female fitting,
At the same time, it is possible to maintain an almost perfect mechanical joining force by the adhesive and also to ensure a perfect sealing state.

According to a fourth aspect, the first fixing ring and the second fixing ring are attached with a required gap, and at least the first fixing ring is provided on the outer periphery of the connecting fitting at a portion corresponding to the gap. Since the ridge having the step portion that substantially abuts against the ring is provided at the end portion of the ring, when the flexible pipe or the first fixing ring is exteriorized to the connection fitting, those end portions are set to the step portion. Positioning for joining can be performed easily just by making abutting contact.

[Brief description of drawings]

FIG. 1 is a partially omitted cross-sectional explanatory view of a flexible pipe joint according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional explanatory view of a main part thereof.

FIG. 3 is a partially omitted cross-sectional explanatory view of a conventional flexible pipe joint.

FIG. 4 is an enlarged cross-sectional explanatory view of a main part thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Flexible pipe joint 12 Flexible pipe 16 Connection metal fitting 18 Exterior part 20 Recessed groove 22 First fixing ring 24 Projection part 26 Adhesive 30 Blade 32 Second fixing ring

Claims (4)

[Claims] 1. An exterior portion of the flexible pipe for the connection fitting, comprising: a cylindrical connection fitting; and a flexible pipe in which a straight pipe portion at an end portion of the connection fitting is exteriorly provided and a fold is continuously formed. A first fixing ring from the outside of the fitting to fix the connection fitting and the flexible pipe, and after fixing the connection fitting and the flexible pipe by the first fixing ring, the outer surfaces of the flexible pipe and the first fixing ring. And a second fixing for covering the blade by further extending the end portion in a direction away from the flexible pipe to cover the blade, and fitting from the outside of the blade end portion, and fixing the blade end portion to the connection fitting. Flexible pipe joint that is equipped with a ring. 2. One or a plurality of recessed grooves are formed on the outer peripheral surface of the connection fitting at a position corresponding to the exterior portion of the flexible pipe, and further, the recessed groove is formed on the inner peripheral surface of the first fixing ring. The flexible pipe joint according to claim 1, wherein a projecting peripheral portion for fitting or projecting is formed. 3. The flexible pipe joint according to claim 2, wherein the concave groove is filled with an adhesive, and in this state, the projecting peripheral portion is fitted into the concave groove. 4. The first fixing ring and the second fixing ring are attached with a required gap therebetween, and at least an end portion of the first fixing ring is provided at an outer periphery of the connecting fitting at a portion corresponding to the gap. The flexible pipe joint according to claim 1, further comprising a ridge having a step portion that closely contacts with each other.