JP3032690B2 - Flexible tube fittings - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint for a flexible tube used for gas piping and the like.

[0002]

2. Description of the Related Art As a conventional joint for a flexible tube of this type, for example, one having a structure as shown in FIG. 5 is known. In this conventional configuration, the cylindrical main body 31 is screwed to a pipe 32 made of gas or the like, and a contact surface 33 is formed inside. The pressing ring 34 is screwed into the cylindrical main body 31, and a retainer 35 is fitted on an inner periphery of an inner end thereof. The flexible tube 36 is inserted into the push ring 34 in a state in which the outer cover 37 is peeled off by a predetermined number of peaks (normally, four peaks), and the distal end of the flexible tube 36 extends from the inner end of the retainer 35 into the cylindrical body 31 by a predetermined amount. (One mountain).

The retainer 35 is formed of a synthetic resin in a ring shape, and a plurality of (usually five or more) elastic projecting pieces 38 are formed on the inner end thereof. Inserts 39 made of a metal plate are buried and formed in the respective elastic protruding pieces 38, and these inserts 39 are formed with claw portions 40 which can be engaged with troughs on the outer periphery of the flexible tube 36.

When the distal end of the flexible tube 36 protrudes by one peak, the push ring 34 is screwed so that the protruding end of the tube 36 comes into contact with the claw 40 of the retainer 35 and the cylindrical main body. 31 is crushed between the contact surface 33 and the contact surface 33. Thus, the flexible tube 36 is connected to the tube 32 in an airtight state.

[0005]

However, the conventional flexible tube joint has the following problems.

(1) Since the retainer 35 is fitted to the inner periphery of the inner end of the push ring 34, the retainer 35
Must be attached to the push ring 34 while reducing its diameter against the expanding force of the elastic protruding piece 38, and the attaching work is difficult.

(2) Since the retainer 35 is fitted on the inner periphery of the inner end of the push ring 34, the flexible tube 36
When each is inserted into the press ring 34, each elastic projection 38 is unlikely to be elastically deformed in the expanding direction. For this reason, the elastic protrusion 38
It is necessary to divide it into a plurality of pieces or more so that it can be easily elastically deformed in the expanding direction, and the manufacturing cost is increased.

(3) Similarly, since the retainer 35 is fitted on the inner periphery of the inner end of the push ring 34, each elastic projection 3
8 is less likely to be elastically deformed in the expanding direction.
Need to be longer.

(4) Since the length of the elastic protruding piece 38 of the retainer 35 is increased, the length of the insert 39 is also increased. When the protruding end of the flexible tube 36 is crushed, the insert 39 is deformed by twisting or the like. And the crushing force may be reduced.

(5) Since the length of the elastic protruding piece 38 of the retainer 35 is increased, the outer
Even when four ridges 7 are peeled off, only one ridge of the tube 36 protruding from the inner end of the retainer 35 can be secured. For this reason, the protruding end of the tube 36 which is crushed by the screwing of the push ring 34 has only one crest, and the pulling force of the tube 36 cannot be sufficiently maintained.
6 and the cylindrical main body 31 could not be sufficiently sealed.

The present invention has been made by paying attention to such problems existing in the prior art. The purpose is to easily attach the retainer to the inner end of the push ring, to simplify the structure of the retainer, to reduce the manufacturing cost, and to reduce the length of the elastic projection of the retainer. An object of the present invention is to provide a flexible tube joint that can be shortened to increase the crushing force of the tube end.

[0012]

In order to achieve the above object, in the invention of the joint for a flexible tube according to the present invention, the retainer is formed in a ring shape from a synthetic resin, and a plurality of retainers are formed at the inner end thereof. the elastic key divided form, a metal plate insert having a claw portion embedded formed in each elastic key, Chakusu <br/> fit the retail Na in the outer periphery of the inner end portion of the push ring At the same time, the inner peripheral surface of the cylindrical body is provided with a tapered surface that decreases in diameter toward the contact surface, and the protruding end of the flexible tube is crushed between the claw portion of the retainer and the contact surface of the cylindrical body. When this is done, the outer peripheral surface of the retainer protruding into the tubular main body from the inner end of the push ring slides against the tapered surface of the cylindrical main body.

According to a second aspect of the present invention, in the joint for a flexible tube according to the first aspect, the retainer is formed with an annular joint surface to be joined to an inner end surface of the push ring.

According to a third aspect of the present invention, in the flexible tube joint according to the first aspect, a slit is formed on an outer periphery of each of the elastic protrusions of the retainer.

[0015]

In the joint for a flexible tube constructed as described above, when a flexible tube is connected to the tubular main body, the push ring is attached to the outer periphery of the inner end of the push ring while the retainer is fitted thereto. Screw into the cylindrical body. After that, when the flexible tube is inserted into the push ring, each elastic projection of the retainer is expanded and deformed against the elastic force, and the claw of each insert climbs over the ridge on the outer circumference of the tube and reaches the predetermined valley. Engages.

The end of the tube projects from the inner end of the retainer into the tubular main body by a predetermined number of peaks. In this state, when the push ring is screwed forward, the protruding end of the tube is crushed between the claw portion of the retainer and the contact surface of the tubular main body, and is brought into close contact with the contact surface. Connected in an airtight state. At this time, a retainer protruding from the inner end of the push ring
The outer peripheral surface of the cylinder slides against the tapered surface in the cylindrical
Is deformed in the radial direction against the elastic force of itself
Advance. Then, the projecting end of the tube is
The contact surface is crushed to ensure close contact.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to FIGS. As shown in FIG. 1, a cylindrical main body 1 is screwed to a pipe 3 made of gas or the like at a male screw portion 2 at one end outer circumference, and a female screw portion 4 is formed at the other inner circumference. The annular contact surface 5 is formed at a central portion in the cylindrical main body 1, and a seal ring 7 is fitted in a groove 6 on the outer periphery thereof. The tapered surface 8 is formed on the inner peripheral surface of the cylindrical main body 1 between the female screw portion 4 and the groove portion 6, and has an inner diameter gradually decreasing toward the groove portion 6.

The cylindrical push ring 9 is provided with an external thread portion 10 on the outer periphery of the inner end.
, The female body 4 of the tubular main body 1 is screwed, and a locking groove 11 is formed on the outer periphery of the inner end. The inner peripheral groove 12 is formed on the inner periphery of the outer end of the press ring 9,
A packing 13 is fitted inside. The outer peripheral groove 14 is formed at the center of the outer periphery of the press ring 9, and a seal ring 15 is fitted in the groove 14.

As shown in FIGS. 1 and 2, the retainer 16
Is fitted on the outer periphery of the inner end of the press ring 9. The retainer 16 has a fitting portion 17 formed of a synthetic resin such as polypropylene in a ring shape, and a plurality of (four) elastic projecting pieces 18 formed at the inner end of the fitting portion 17 so as to project therefrom.
It consists of An annular locking projection 19 is formed on the inner peripheral surface of the fitting portion 17, and when the locking projection 19 engages with the locking groove 11 of the pressing ring 9, the retainer 16 moves the pressing ring 9.
Is locked and held on the outer periphery of the inner end of the.

Four inserts 20 made of a metal plate such as brass are embedded in each of the elastic protruding pieces 18 of the retainer 16, and claw portions 21 are formed at their inner ends by bending toward the center. I have. The through hole 22 is formed at the center of each insert 20, and when the retainer 16 is formed, a synthetic resin is inserted into the through hole 22 and hardened, whereby each insert 2 is formed.
0 is retained in the elastic protruding piece 18 so as not to come off.

An annular joint surface 23 is formed on the end surface of the elastic projection 18 of the retainer 16, and when the retainer 16 is fitted on the outer periphery of the inner end of the press ring 9, the joint surface 2 is formed.
3 is joined to the inner end face of the press ring 9. Each of the two slits 24 is formed on the outer peripheral surface of each of the elastic projection pieces 18 of the retainer 16 at predetermined intervals in parallel in the axial direction.
4 facilitates elastic deformation of the elastic projection 18 in the expanding direction.

As shown in FIG. 1, the flexible tube 25 is composed of a bellows-shaped tube main body 26 made of metal and a synthetic resin jacket 27 coated on the outer periphery of the tube main body 26. And the tube body 2
The flexible tube 25 is inserted into the push ring 9 in a state in which the jacket 27 has been peeled off from the end portion by a predetermined number of peaks (for four peaks). At this time, the claw 21 of the retainer 16 is engaged with a predetermined valley on the outer periphery of the tube main body 26, and the end of the tube main body 26 is inserted into the cylindrical main body 1 from the inner end of the retainer 16 by a predetermined amount (2 Only). In this embodiment, a flexible tube 25 having a nominal diameter of 8A to 32A is used.

As shown in FIG. 1 and FIG.
When the push ring 9 is screwed into the cylindrical main body 1, the push ring 9
It is used by being detachably fitted to the outer periphery of the device. The spacer 28 is formed of a synthetic resin to a predetermined thickness, and a fitting recess 29 and a pair of elastic holding pieces 30 are formed below the spacer 28. The fitting of the spacer 28 restricts the screwing position of the push ring 9 to the cylindrical main body 1 to a predetermined position. In this state, the flexible tube 25 is inserted into the push ring 9.
Is inserted, the end of the tube body 26 can be reliably projected from the inner end of the retainer 16 by two ridges.

Next, the operation of the joint for a flexible tube configured as described above will be described. When connecting the flexible tube 25 to the tubular main body 1 by using the flexible tube joint, first, as shown in FIG. 1, the retainer 16 is attached to the inner end of the push ring 9. At this time, each elastic projection 18 of the retainer 16
Is pushed in while being expanded against the elastic force, and the retainer 16 may be fitted to the outer periphery of the inner end of the push ring 9,
The work of attaching the retainer 16 can be easily performed.

After that, the spacer 28
Is fitted against the elastic force of the pair of elastic holding pieces 30.
In this state, when the male thread portion 10 of the push ring 9 is screwed into the female thread portion 4 of the tubular main body 1, the push ring 9 is screwed into the tubular main body 1 to a predetermined position regulated by the spacer 28. Is done.

On the other hand, as for the flexible tube 25, the jacket 27 is peeled off from the end of the tube body 26 by a predetermined number of peaks (for four peaks) in advance. When the flexible tube 25 is inserted into the press ring 9 in this state, the claw portions 21 of the respective inserts 20 are expanded and deformed while the respective elastic protruding pieces 18 of the retainer 16 are expanded against the elastic force. Over the peaks and engage with the predetermined valleys. Then, an end of the tube main body 26 projects from the inner end of the retainer 16 into the tubular main body 1 by a predetermined amount (two peaks).

At this time, since the retainer 16 is fitted on the outer periphery of the inner end of the push ring 9, each elastic projection 18 of the retainer 16 easily elastically deforms in the expanding direction. Further, since a pair of slits 24 are respectively formed on the outer periphery of each elastic protruding piece 18, the expansion deformation of the elastic protruding piece 18 is further facilitated. Therefore, the flexible tube 25 can be easily inserted into the push ring 9 even if the number of divisions of the elastic projection piece 18 is reduced to about four. Therefore, retainer 1
6 can be simplified, and its manufacturing cost can be reduced.

Further, as described above, since the respective elastic projections 18 of the retainer 16 are easily elastically deformed in the expanding direction, even if the length of the elastic projections 18 is shortened, the flexible tubing into the push ring 9 is prevented. 25 does not become difficult to insert.
Therefore, the length of the joint in the axial direction can be shortened, and the entire joint can be made compact even when two ridges at the tip of the flexible tube 25 are crushed.

Thereafter, the spacer 28 is removed from the outer periphery of the push ring 9 and the push ring 9 is screwed with respect to the cylindrical main body 1, and as shown in FIG. It engages with the tapered surface 8 in the main body 1 and is deformed in the diameter-reducing direction against its own elastic force. In this state, the protruding end of the tube main body 26 is crushed between the claw portion 21 of the retainer 16 and the contact surface 5 of the tubular main body 1 as the pressing ring 9 advances. The end face of the crushed portion is in close contact with the contact surface 5 of the tubular main body 1, and the outer peripheral edge of the crushed portion is in close contact with the seal ring 7 in the tubular main body 1. This allows
The flexible tube 25 is connected to the tubular main body 1 in an airtight state.

At this time, since the length of the elastic projecting piece 18 of the retainer 16 is shortened and the length of each insert 20 is also shortened, when the projecting end of the tube body 26 is crushed,
There is no possibility that deformation such as twisting occurs in each insert 20. Further, since the joining surface 23 of the retainer 16 is joined to the inner end surface of the press ring 9, the retainer 1
The pressing force is effectively transmitted to 6. Accordingly, as the pressing ring 9 advances, a strong crushing force is applied to the protruding end of the tube body 26 from the joint surface 23 of the retainer 16 via each insert 20, and the protruding end is securely flattened. Can be crushed.

Further, since the length of the elastic protruding piece 18 of the retainer 16 is shortened as described above, even if the outer cover 27 of the flexible tube 25 is peeled off by four peaks as in the conventional case, the retainer can be retained. The number of ridges of the tube body 26 protruding from the inner end of the ridge 16 can be secured for two ridges.
For this reason, the number of peaks of the protruding end of the tube main body 26 to be crushed becomes two, and the end face and the outer peripheral edge of the crushed portion are closely contacted with the contact surface 5 and the seal ring 7 in the cylindrical main body 1. Can be done. Therefore, the flexible tube 2
5 can be improved, and the space between the flexible tube 25 and the tubular main body 1 can be sufficiently sealed.

The present invention can be embodied with the following modifications. (A) The width or the number of the slits 24 formed on the outer peripheral surface of each elastic projection 18 of the retainer 16 is increased. (B) The number of the elastic projecting pieces 18 in the retainer 16 is set to 3
Change to one.

Further, technical ideas other than the claims are described below together with their effects. (1) An annular locking projection is formed on the inner peripheral surface of the fitting portion of the retainer, and a locking groove is formed on the inner periphery of the pressing ring, and the locking projection of the retainer is locked by the pressing ring. The joint for a flexible tube according to claim 1, wherein the joint is engaged with the groove. With this configuration, the retainer can be reliably locked and held on the outer periphery of the inner end of the push wheel. (2) The joint for a flexible tube according to claim 1, wherein a spacer formed to a predetermined thickness is detachably fitted to an outer periphery of the push ring. According to this configuration, the screwing position of the push ring with respect to the cylindrical main body can be regulated, and when the flexible tube is inserted into the push ring, its end can be reliably projected from the inner end of the retainer by a predetermined length. it can. (3) The flexible tube joint according to claim 1, wherein a tapered surface is formed on the inner peripheral surface of the tubular main body so as to be in sliding contact with the outer peripheral surface of the retainer so that the inner diameter becomes smaller toward the inside. With this configuration, the retainer is attached to the inner end of the push ring, the flexible tube is inserted into the push ring, and then the push ring is tightened to the cylindrical body, and the retainer slides on the tapered surface in the cylindrical body. It moves forward while being reduced in diameter. Therefore,
The claw portion of the insert of the retainer is pressed by the flexible tube, and the protruding end portion of the flexible tube is crushed by the contact surface in the tubular main body, so that the flexible tube is more securely in close contact.

[0034]

The present invention is configured as described above, and has the following effects. According to the first aspect of the present invention, it is possible to easily attach the retainer to the outer periphery of the inner end of the push ring while expanding each elastic protruding piece against the elastic force. For this reason, the work of attaching the retainer can be performed efficiently.

Further, since the retainer is fitted on the outer periphery of the inner end of the push ring, and each elastic projection of the retainer is easily elastically deformed in the expanding direction, the number of divisions of the elastic projection can be reduced. it can. Therefore, the structure of the retainer is simple, and the manufacturing cost can be reduced.

Further, since each elastic projection of the retainer is easily elastically deformed in the expanding direction, the length of the elastic projection of the retainer can be shortened. For this reason, the length of the joint in the axial direction can be reduced, and the entire joint can be formed small.

In addition, since the length of the elastic projection of the retainer is shortened, the length of the insert can be shortened.
For this reason, when the protruding end of the flexible tube is crushed, it is possible to prevent the insert from being deformed by twisting or the like, and it is possible to increase the crushing force of the tube end by the retainer.

Moreover, since the length of the elastic protruding piece of the retainer is shortened, the number of the ridges of the tube projecting from the inner end of the retainer increases when the sheath of the flexible tube is peeled off by a predetermined amount. For this reason, the number of peaks of the protruding end portion of the crushed tube is increased, and the pulling force of the tube is improved, and the space between the tube and the tubular main body can be sufficiently sealed. In addition, a tape
A rib surface is provided, and a rib projecting from the inner end of the push ring into the cylindrical body
So that the outer peripheral surface of the tena is in sliding contact with the tapered surface of the cylindrical body
When crushing the protruding end of the tube,
The outer peripheral surface of the retainer protruding from the inner end of the loop is inside the cylindrical body.
Forward while being slid into contact with the tapered surface of
And make the protruding end of the tube come into close contact with the contact surface of the cylindrical body.
And can be reliably crushed.

According to the second aspect of the present invention, when the push ring is screwed forward, the joint surface of the retainer is joined to the inner end surface of the push ring, and the projecting end of the tube is further strengthened. Can be crushed.

According to the third aspect of the present invention, since the slit is formed on the outer periphery of each elastic projection of the retainer,
The elastic protruding pieces are more easily elastically deformed in the expanding direction.

[Brief description of the drawings]

FIG. 1 is a partially broken side view showing a joint for a flexible tube according to an embodiment.

FIG. 2 is a front view showing a retainer in the joint.

FIG. 3 is a front view showing a spacer when a tube is connected with the joint.

FIG. 4 is a partially cutaway front view showing a state where the press wheel is rotated by tightening from FIG. 1;

FIG. 5 is a partially broken side view showing a conventional flexible tube joint.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cylindrical main body, 5 ... Contact surface, 9 ... Pressing ring, 11 ... Locking groove, 16 ... Retainer, 18 ... Elastic protrusion, 19 ... Locking projection, 20 ... Insert, 21 ... Claw part, 23 ... Joint surface, 2
4 ... Slit, 25 ... Flexible tube.

Continuing from the front page (72) Inventor Nobuhiko Hayashi 57, Tominaga, Miyama-cho, Yamanashi-gun, Gifu Prefecture Inside of Onda Manufacturing Co., Ltd. (72) Inventor Toshio Shibuchi 2-10-16 Minamikagaya, Suminoe-ku, Osaka, Osaka Shinwa Sangyo Co., Ltd. (56) Reference Hikaru 3-125983 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) F16L 33/00

Claims (3)

(57) [Claims] 1. A tubular body having an abutment surface therein, a push ring screwed into the tubular body, a flexible tube inserted into the push ring, and an inner end of the push ring. A retainer having a plurality of claw portions engageable with a valley portion on the outer periphery of the flexible tube, and a predetermined amount of the end of the flexible tube inserted into the push ring is inserted into the cylindrical main body from the inner end of the retainer. With the protruding end of the flexible tube being screwed forward, the protruding end of the flexible tube is crushed between the claw portion of the retainer and the abutting surface of the tubular main body so that the flexible tube comes into close contact with the abutting surface. in fitting for a flexible tube to said retainer is formed in a ring shape by a synthetic resin, a plurality of elastic key splits formed on its inner end, <br/> in each elastic key has a pawl portion Buried metal plate insert And, the fitting of the retail Na on the outer periphery of the inner end of the pushing wheel Chakusu Rutotomoni, the inner circumferential surface of the cylindrical main body provided with a tapered surface whose diameter decreases toward the abutment surface of the flexible tube projecting end When the portion is crushed between the claw portion of the retainer and the contact surface of the cylindrical body, the outer peripheral surface of the retainer protruding into the cylindrical body from the inner end of the push ring slides on the tapered surface of the cylindrical body. For flexible tubes configured as described above. 2. The flexible tube joint according to claim 1, wherein the retainer has an annular joint surface joined to an inner end surface of the push ring. 3. The flexible tube joint according to claim 1, wherein a slit is formed on an outer periphery of each of the elastic projections of the retainer.