JPH0242954Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention is a flexible metal pipe that can suitably connect flexible metal pipes with thin peripheral walls with corrugated cross-sections used for indoor gas piping, hot water supply piping, etc. This invention relates to connection fittings for pipe relays.

(Prior Art) A conventional general metal flexible tube connection fitting has, for example, an outer periphery on one end connected to a header, and a flexible metal tube connected to an inner periphery on the other end. but,
Recently, there has been a growing demand for relay connecting fittings for connecting flexible metal tubes, not only in such cases.

In this case, since the metal flexible tube used for gas piping etc. has a thin corrugated peripheral wall, it can be easily bent and deformed along the piping route. It is weak against twisting and easily damaged by twisting.

Therefore, when connecting flexible metal tubes to each other using a connecting fitting, it is necessary to take appropriate measures to prevent the flexible metal tubes from being twisted.

In view of the above circumstances, it is an object of the present invention to provide a connecting fitting for a relay that can reliably connect flexible metal tubes in an appropriate state without twisting.

(Structure of the invention) In order to achieve the above object, the connecting fitting for a metal flexible pipe relay according to the invention has a plurality of substantially cylindrical connection ports into which the ends of the metal flexible pipes are inserted and accommodated. At the back of the connection port, there is a stopper piece that faces the end of the flexible metal tube, and each cylindrical connection port has a connection fitting body with a threaded portion on the outer peripheral surface, and a connection A cap nut is screwed onto each threaded portion of the metal fitting body, and a flexible metal tube is externally engaged with the flexible metal tube, which is pushed and moved into the accommodation portion in the connection port by tightening the cap nut. a retaining ring that can be deformed to reduce its diameter; the inner peripheral surface of the connecting fitting main body in the area where the retaining ring enters the accommodating portion is moved as the retaining ring is pressed by the cap nut; It is composed of a tapered diameter reduction deformation surface that gradually reduces the diameter of the ring and a non-tapered rotation prevention surface that extends from the smallest diameter end of the diameter reduction deformation surface in the pressing movement direction of the retaining ring. It is.

(Function) According to this configuration, by tightening one of the cap nuts, one of the retaining rings is gradually deformed in diameter by the diameter-reducing deformation surface and moved into the accommodation portion in the connection port. Afterwards, it is pressed and moved to the end of the plunge area inside the connection body while being held in the most reduced diameter state by the rotation prevention surface, and one of the metal flexible tubes is relayed. It will be connected to one side of the connection fitting. Further, the other metal flexible tube is also connected to the other side of the relay connecting fitting in the same manner as described above by tightening the other cap nut. In this case, as the retaining ring is reduced in diameter by the diameter reducing deformation surface, the repulsive force received by the retaining ring from the metal flexible tube in the direction of diameter expansion increases, causing the retaining ring to become smaller. Due to the contact pressure on the inner peripheral surface of the connecting fitting body, the frictional engagement force becomes larger than the frictional engagement force between the cap nut and the retaining ring, and the retaining ring rotates as the cap nut rotates. Instead, it is held in a state where it is integrated with the connecting fitting main body, causing slippage between it and the cap nut. The retaining ring is maintained in the above state by the rotation preventing surface until the tightening of the cap nut is completed. Therefore, the retaining ring does not always rotate with the rotation of the cap nut during the period from the start to the end of connection of the flexible metal tube.

(Example) Next, the configuration of the present invention will be specifically described based on the example shown in FIGS. 1 to 5.

That is, the relay connecting fitting of this embodiment includes a connecting fitting main body 11, a pair of cap nuts 12, 12 screwed onto the connecting fitting main body, and these cap nuts 1.
It is provided with a pair of retaining rings 13, 13 which can be pressed and moved to push into the connection fitting main body 11 by a predetermined amount by tightening the retaining rings 2, 12, respectively.

The connection fitting main body 11 has accommodating portions 11a, 11a which form cylindrical connection ports 17, 17 at both ends and accommodate the metal flexible tubes 15 by inserting them from both sides, respectively. An annular stopper piece 18 facing the end of the metal flexible tube 15 is integrally formed at the back of the tube. Male screw portions 17a, 17a are carved on the outer periphery of the connection port portions 17, 17, respectively, for screwing the cap nuts 12, 12.
On the inner periphery thereof, there are retaining rings 13, 13, respectively.
In the intrusion region l, tapered diameter reduction deformation action surfaces 17b, 17b that gradually narrow inward from the open ends of the connection ports 17, 17, and this diameter reduction deformation action surface 17.
non-tapered, ie, uniform diameter, rotation blocking surfaces 17c, 17c extending inward from the smallest diameter ends of b, 17b;
is formed. Furthermore, an annular pressing protrusion 18a and an annular recess 18b are formed on both side surfaces of the stopper piece 18. This annular recess 18b
is formed continuously with the rotation prevention surface 17c, and engages and holds the O-ring 14.

Each retaining ring 13 has a cylindrical main body portion 13a.
At one end thereof, a locking portion 13 is bent outward in a V-shape and is capable of abutting and locking the end wall 12a of the cap nut 12.
b, and the other end thereof is formed with an engaging portion 13c that can be externally engaged with one of the troughs 15a of the flexible metal tube 15, which protrudes inward, and both ends in the circumferential direction. A pair of half-shaped parts 13', 1, each of which can form a right circular shape when the parts abut against each other.
3'. Note that each half-shaped portion 13' is obtained by pressing a plate material such as a steel plate, for example.

By the way, regarding the retaining ring 13,
In a state where both circumferential ends of both half-shaped portions 13' and 13' are abutted, the outer diameter of the main body portion 13a is the same or approximately the same as the diameter of the rotation prevention surface 17c of the connection fitting main body 11, Further, the inner diameter of the end portion of the engaging portion 13c is set to be slightly smaller (about 0.3 to 0.5 mm) than the outer diameter of the valley portion 15a of the flexible metal tube 15.

Therefore, according to the relay connecting fitting configured as described above, the engaging portion 13c of one of the retaining rings 13 is separated from the end of one of the flexible metal tubes 15 by two.
By externally engaging the third to third valley portions 15a, and then screwing and tightening the connection fitting main body 11 of one cap nut 12, that is, one connection opening portion 17, one metal flexible The pipe 15 can be connected to one side of the relay fitting without twisting the pipe 15.

That is, as the cap nut 12 is tightened, the locking portion 13b of the locking ring 13 is pressed against the end wall 12a of the cap nut 12, and the locking ring 13 is moved in the tightening direction of the cap nut 12. Along with this, the main body portion 13a of the retaining ring 13 is gradually reduced in diameter by the diameter reduction deformation action surface 17b of the connection fitting main body 11 (see FIGS. 2 and 4). In other words, the circumferential ends of the half-split portions 13', 13' are gradually brought closer to each other, and the engaging portion 13c of the retaining ring 13 bites into the valley portion 15a of the flexible metal tube 15. be.

When the retaining ring 13 is further pressed and moved as the cap nut 12 is tightened, the end of the main body 13a of the retaining ring 13 also reaches the minimum diameter end of the diameter reducing deformation surface 17b of the connecting fitting main body 11. Then, the amount of diameter reduction deformation becomes maximum, and thereafter, the retaining ring 13 maintains the diameter reduction deformation as described above on the rotation blocker action surface 17c of the connection fitting main body 11.
While being maintained by the connection fitting main body 11, it is moved into the connection fitting main body 11 (see FIGS. 3 and 5).

In this state, both end portions in the circumferential direction of the two half-shaped portions 13', 13' are in abutment with each other or in a state close to this, and the engaging portion 13c of the retaining ring 13 is connected to the flexible metal tube. This is inserted into the valley portion 15a of No. 15 with its diameter reduced to some extent (for example, 03 to 0.5 mm). Therefore, the frictional engagement force between the connecting fitting body 11 and the retaining ring 13 becomes extremely large due to the repulsive force caused by the diameter reduction deformation of the metal flexible tube 15, that is, the frictional engaging force between the cap nut 12 and the retaining ring 13 increases. Therefore, as the cap nut 12 moves, the retaining ring 13 does not rotate together, causing slippage between the two 12 and 13, and the flexible metal tube 15 This effectively prevents twisting from occurring.

In this way, the retaining ring 13 is attached to the cap nut 12.
As the metal flexible tube 15 rotates, the metal flexible tube 15 is moved under pressure without rotating together, and the metal flexible tube 15 is also moved into the connection fitting main body 11. After the end of the flexible tube 15 is brought into contact with the annular pressing protrusion 18a of the connection fitting main body 11, the cap nut 1 of the retaining ring 13 is removed.
2, the pipe end side portion 15b is pressed by the valley portion 15a in which the engagement portion 13c is engaged, and the engagement portion 13c of the retaining ring 13 and the annular pressing protrusion 18a are also pressed. As a result, they were gradually crushed.

Then, by tightening the cap nut 12 to the maximum extent and pushing the retaining ring 13 to a predetermined position inside the connecting fitting main body 11, the connection of the metal flexible tube 15 is completed (see Fig. 1). .

The connection of the other flexible metal tube 15 to the relay connector is also performed in the same manner as described above.
5 is not subjected to the torsional force when tightening the cap nut 12, that is, the metal flexible tube 15 does not rotate together, and this other cap nut 12 is connected to the connection fitting main body 11.
Since the metal flexible tube 1 is tightened with a tool engaged with the polygonal engaging portion 11b on the outer periphery of the central portion of the connected metal flexible tube 1 so as not to rotate.
No torsional force is applied to the flexible tubes 15, 15, and the flexible tubes 15, 15 can be connected to the relay fitting in an appropriate state.

In addition, in such a connection structure of the metal flexible tube 15, the tube end side portion 15 of the metal flexible tube 15
When b is crushed, the engaging portion 13c of the retaining ring 13 and the annular pressing protrusion 18a of the connecting fitting main body 11
Since the metal flexible tube 15 is clamped under pressure, the pulling out of the metal flexible tube 15 is reliably prevented unless the metal flexible tube 15 is broken by the pulling force.
The pull-out prevention function is improved compared to the case where the metal flexible tube 5 is prevented from being pulled out by the engagement action of the retaining ring 3 as in the case of a conventional connecting fitting.
By the way, the tube end side portion 15b of the metal flexible tube 15
may be crushed to some extent in advance with an appropriate tool, as is commonly done in the past.
In this embodiment, there is no need to do this, which is extremely convenient. In addition, the retaining ring 1
3 compresses the O-ring 14 to ensure a seal between the connection fitting main body 11 and the flexible metal tube 15. However, if the O-ring 4 is lost due to a fire or the like, or if the seal by the O-ring 14 Even if the function deteriorates, the end portion 15 of the metal flexible tube 15
Since b is squeezed between the connecting fitting body 11 and the retaining ring 13 in a collapsed state, the sealing performance between the connecting fitting body 11 and the flexible metal tube 15 is not significantly degraded.

Note that the relay connection fitting according to the present invention is not limited to the above-mentioned embodiment, and for example, a plurality of engagement portions 13c of the retaining ring 13 are formed, and a plurality of valley portions 15a of the metal flexible tube 15 are formed. It may be arranged so that it can be engaged with. In addition, the retaining ring 13 is
A pair of pressed half-shaped parts 13', 1
For example, it may be divided into three or more parts in the circumferential direction, or it may be expandable by cutting off a part in the circumferential direction. When creating a split structure, it may be obtained by cutting and separating a ring-shaped ring, but in this way, when both circumferential ends of the split portion are abutted, each part will not be true. It does not have a circular shape, and it is difficult to crush the end portion 15b of the metal flexible tube portion 15 uniformly in the circumferential direction. Furthermore, the present invention is not limited to the relay connecting fitting for connecting a pair of flexible metal tubes 15, 15 as in the above embodiment, but also for a fitting for inserting and connecting flexible metal tubes from three sides, or for connecting a pair of flexible metal tubes with a diameter of the inserted portion. It goes without saying that the present invention can be applied to different diameter teeth as well as to resisters.

(Effects of the invention) According to the relay connection fitting of the invention, when tightening each cap nut individually, each retaining ring does not rotate together with the rotation of the cap nut. Metal flexible tubes can be reliably connected to each other without twisting.

Moreover, as in the present invention, the retaining ring is brought into pressure contact with the inner circumferential surface of the connecting fitting body, and its frictional resistance allows
For taps where the retaining ring is pushed in with a cap nut without causing the retaining ring to rotate,
Since the cap nut must be rotated with a certain amount of force, there is a risk that the cap nut may be incompletely tightened during field work, but in the case of this invention, the inner peripheral surface of the connection fitting body consists of a tapered diameter reduction deformation surface and a non-tapered rotation prevention surface extending from the smallest diameter end of this diameter reduction deformation surface in the pressing movement direction of the retaining ring. A situation in which the retaining ring has been reduced in diameter by the diameter reduction deformation surface and has entered a pushed-in state in which the retaining ring does not rotate together, that is, it takes a certain amount of force to rotate the cap nut, but the cap nut still rotates with the same force. During the rotation operation of the cap nut, it is possible to know the transition from a situation in which the nut can be moved to a final position in which it becomes difficult to rapidly rotate the cap nut. Therefore, by making the operator aware of this changing situation, it is possible to effectively prevent on-site work from ending with an incompletely tightened cap nut.

[Brief explanation of the drawing]

Figures 1 to 5 show an embodiment of the connecting fitting according to the present invention. Figure 1 is a half-cut longitudinal side view showing the completed state of the metal flexible pipe connection work, and Figure 2 is the same work. Fig. 3 is a half-cut longitudinal side view showing the state immediately after the start of the work; Fig. 3 is a half-cut longitudinal side view showing the state before completion of the work; Fig. 4 is a longitudinal front view of the main part along the - line in Fig. 2; FIG. 5 is a longitudinal sectional front view of the same essential parts taken along the - line in FIG. 3. 11... Connection fitting main body, 11a... Accommodation part, 1
2... Bag nut, 13... Retaining ring, 13'
... Half-shaped part, 13a ... Main body part, 13b ...
...Locking part, 13c...Engaging part, 14...O ring, 15...Metal flexible tube, 17...Connection port, 1
7a...Male thread, 17b...Diameter reduction deformation surface, 1
7c...Rotation prevention surface, l...Protrusion area of the retaining ring in the connection fitting body, 18...Stopper piece.

Claims (1)

[Scope of utility model registration request] It has a plurality of substantially cylindrical connection openings into which the ends of the metal flexible tubes are inserted and accommodated, and has stopper pieces at the back of the connection openings facing the ends of the metal flexible tubes,
Further, on the outer circumferential surface of each cylindrical connection port, there is provided a connection fitting main body having a threaded portion, a cap nut that is individually screwed onto each threaded portion of the connection fitting main body, and by tightening the cap nut, the connection port is closed. a retaining ring that can be deformed to reduce its diameter and externally engaged with a flexible metal tube, the retaining ring being pressed and moved in order to enter a housing part in the housing, the retaining ring being pushed into the housing part; The inner circumferential surface of the connecting fitting main body in the area is formed by a tapered diameter reducing deformation surface that gradually reduces the diameter of the retaining ring as it is pressed and moved by the cap nut, and from this diameter reducing deformation surface from the smallest diameter end. A connecting fitting for a metal flexible pipe relay, characterized in that the fitting has a non-tapered rotation preventing surface extending in the pressing movement direction of the retaining ring.