JP3411546B2 - Pipe fitting - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a pipe joint.

[0002]

2. Description of the Related Art A conventional pipe joint for connecting pipes for supplying water or hot water, which is made of a synthetic resin material, has a pipe a fitted and hooked in a retaining state as shown in FIG. Joint body c having an insertion tube portion b formed with a plurality of stages of circumferential taper (bamboo shoot shape), a split ring e having a slit d, and a cap nut f for reducing the diameter of the split ring e. , A retaining ring h fitted in the cap nut f, and the like have been used.

In such a pipe joint, first, the pipe a
Then, the cap nut f, the retaining ring h, and the split ring e are fitted in, and the pipe a is pushed into the insertion tube portion b of the joint body c to be fitted therein, and then the cap nut f is fitted in the joint body c.
The split ring e is reduced in diameter by being screwed into the threaded portion g, so that the pipe a is retained in the insertion tubular portion b of the joint main body c in a retaining state.

Further, the retaining ring h is attached to the joint body c.
Even if a pulling force (from the insertion tube portion b) is generated on the pipe a, the outer surface of the pipe a fitted on the insertion tube portion b of FIG. Is prevented from being pulled out. That is, as shown in FIG. 14, on the inner peripheral side of the retaining ring h, there are a plurality of circumferentially divided tooth portions i.
Are provided, and their tooth portions i ... Hook on the outer peripheral surface of the pipe a.

[0005]

However, since the conventional pipe joint is made up of three parts, the parts management is complicated,
Especially when many pipe fittings are required,
It is not easy to align these parts without excess or deficiency, and there is a problem that the parts are easily lost. Moreover,
The assembly work requires three steps and is laborious,
The efficiency did not improve.

Further, since the sealing property is secured by tightening the pipe a from the outer peripheral surface, when there is a dimensional change due to variations in the diameter of the pipe a or thermal deformation,
In some cases, sufficient water-stopping performance could not be ensured. In particular, under environmental conditions where the temperature change is large, it may not be possible to stably maintain high water-stopping performance for a long period of time.

Further, the tooth portions i ... Of the retaining ring h are
Since the ring body is formed by punching (using a press or the like), the gap between the adjacent tooth portions i, i is set to be large, and the contact area of the tooth portion i ... The surface pressure increases and the load on the pipe a increases. That is, the tooth portions i ... bite into the pipe a, and the pipe a is damaged by cutting or the like.

In view of the above, the present invention has good workability in assembling, is easy to manage and procure parts without damaging the pipes to be connected, is less likely to lose parts, and can be used for a long period of time. It is an object of the present invention to provide a pipe joint that can maintain stable water stop performance.

[0009]

To achieve the above object, according to the Invention The pipe joint according to the present invention includes: a fitting body having an insertion cylinder portion inserted to an end portion of the pipe for the connection, on Symbol Insert A seal member mounted in the concave circumferential groove of the tubular portion, a tightening ring body with a slit for tightening the end portion of the pipe fitted on the insertion cylindrical portion with an elastic tightening force, and the tightening body. The expansion ring is detachably held by the end of the slit so as to expand the diameter of the tightening ring against the elastic force of the ring, and abuts against the tip of the pipe to be inserted and expands. The inner peripheral side engages with the diameter piece, the joint main body having the insertion cylinder portion inserted into the end portion of the pipe to be connected, and the outer peripheral surface of the pipe externally fitted to the insertion cylinder portion in a retaining state so as not to come off. A retaining ring, and notches are formed on the inner peripheral side of the retaining ring at equal intervals in the circumferential direction. In which a plurality of teeth is provided.

Further, the outer peripheral surface of the insertion tube portion is provided with a recess at a portion corresponding to the tooth portion of the retaining ring.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in detail with reference to the drawings showing the embodiments.

FIG. 1 is a front sectional view showing an embodiment of a pipe joint C, and FIG. 2 is a front sectional view showing a state where pipes are connected. In these drawings, reference numeral 1 is a water supply or hot water supply to be connected. A pipe for business use, which is made of a synthetic resin material such as cross-linked polyethylene or polybutene. Reference numeral 2 denotes a joint body, which has an insertion tube portion 3 inserted into the end portion of the pipe 1 at one end side thereof.

Reference numeral 4 denotes a seal member (O-ring or the like), which is mounted in the concave circumferential groove 7 of the insertion tube portion 3 of the joint body 2. Reference numeral 5 denotes a tightening ring body made of spring steel or the like, having a slit (cutting portion) 51 in the axial direction, and the end portion of the pipe 1 fitted on the insertion tube portion 3 is elastically tightened. tighten. 6 is an expanding piece,
It is made of high-rigidity steel material, and in the initial state shown in FIG. 1, it is removably press-fitted into the end of the slit 51 against the elastic force of the tightening ring body 5, and the tightening ring body 5 is removed. The diameter is enlarged to the extent that the pipe 1 can be inserted.

Reference numeral 14 denotes a cover for covering the tightening ring body 5, and a female screw 141 formed on the inner circumference of the base of the cover 14 is a male thread formed on the outer circumference of the insertion tube 3 of the joint body 2 near the base. screw
A ring-shaped escape space 16 for screwing the expanded diameter piece 6 detached from the slit 51 of the tightening ring body 5 is provided between the cover 14 and the insertion cylinder portion 3 which is screwed to 19. Is forming.
The cover 14 is preferably made of a transparent resin such as PA (polyamide, nylon), PES (polyether sulfone), or PC (polycarbonate), so that the expansion piece 6 can be easily removed from the outside (visually). Can be confirmed.

Reference numeral 8 denotes a retaining ring disposed on one end side (end portion) of the cover 14, which is a SUS material (for example, SUS304-
It is made of a highly rigid sheet metal material having elastic force such as CSP (1 / 2H), and is formed with notches at equal intervals in the circumferential direction on the inner peripheral side thereof and the insertion direction A of the pipe 1 (see FIG. 1). )
It is detachably tightened and fixed by a cap nut 10 that has a plurality of tooth portions 12 that are bent to be hooked on the outer peripheral surface of the pipe 1 and that is screwed into a male screw 9 formed on the outer peripheral surface of the cover 14. Has been done. The cap nut 10 is made of a copper alloy such as brass or a plastic composite material (for example, modified PPO (GF
30)) etc.

More specifically, the retaining ring 8 is
It is formed as follows. That is, FIG. 3 shows a side view (A) and a front cross-sectional view (B) during formation of the retaining ring 8, showing a predetermined annular body 23, which is cut from the inner peripheral surface thereof to a predetermined length in the radial direction. 4A and 4B, the recesses 24 are provided at a predetermined pitch (center angle) in the circumferential direction to form a plurality of (18 in the present embodiment) tooth portions 12 ... like,
The tooth portions 12 are bent in the axial direction to form a petal-shaped (Chrysalis-shaped) retaining ring 8.

The cut portion 24 (a gap between the adjacent tooth portions 12 and 12) is formed by cutting with a scissors by a press, not by using a press. Also, the notch
At the end of 24 (outward in the radial direction), by drilling,
A small hole (circular shape) 25 is provided therethrough. Therefore, the tooth 12 ...
Can be bent easily and adjacent teeth
The gap between 12 and 12 can be set small (compared to the conventional example shown in FIG. 14).

On the outer peripheral surface of the insertion tube portion 3, a (annular) recess is formed at a portion corresponding to (opposing) the tooth portions 12 of the retaining ring 8.
21 is provided, and a (annular) stepped portion 22 is provided at a portion corresponding (opposing) to the tightening ring body 5. Further, on the other end side (end portion) of the joint body 2, a male screw 17 that is screwed into a member (not shown) to be connected is formed.

The tightening ring body 5 is in its free state (reduced diameter state).
5 is a side view (A) of FIG. 5 and an enlarged view (B) and FIG. 6 of a main part (inside a virtual circle of FIG. 5A), and FIG.
As shown in a side view (A) of FIG. 8 and an enlarged view (B) of FIG. 8 and an essential part (inside a virtual circle of FIG. 7A), the slit 51 is
A protrusion 521 formed on one end face 52 is formed in a concave-convex fitting shape so as to fit into a recess 531 formed on the other end face 53. By forming the slit 51 in such a shape, the tightening force on the pipe 1 can be continuously applied without interruption in the circumferential direction, and the pipe 1 is uniformly pressed against the seal member 4 in a closed loop shape. It is possible to prevent fluid leakage in the axial direction and improve the sealing performance.

Further, the inner end edges of both end faces 52, 53 which face each other across the slit 51 are rounded (R).
It is chamfered into a shape. Radius of curvature R of the inner edge
May be appropriately set according to the diameter, wall thickness, material, etc. of the pipe 1 to be connected, but when the outer diameter of the tightening ring body 5 in the free state is 15 to 35 mmφ, R = 0.4 to 0.6 It is preferably set to about mm. In this manner, by chamfering the inner end edge portions of the both end surfaces 52, 53 in a rounded (R) shape, the diameter reduction operation of the tightening ring body 5 can be performed without scratching the surface of the pipe 1 at the time of diameter reduction. It becomes smoother and a strong tightening force can be applied to the pipe 1.

As shown in the enlarged perspective view of FIG. 9 and the front view (A) and side view (B) of FIG. 10, the diameter expanding piece 6 has a slit 51.
A press-fitting portion 61 that is press-fitted into the press-fitting portion and a restricting portion 62 that contacts the side end surface of the tightening ring body 5 and restricts the press-fitting position of the expanded diameter piece 6 are integrally formed. Pressed contact surfaces 611, 611 held by the slit 51 of the tightening ring body 5 are formed on both outer diameter sides (when press-fitting) of the press-fitting portion 61.

Further, the press-fitting portion 61 of the expanded diameter piece 6 is provided with a bent portion 612 at its end portion, and the bent portion 612 is continuously provided with a restriction portion 62. Specifically, the press-fitting portion 61 is formed by bending one side of the rectangular flat plate, and the restricting portion 62 is a rectangular flat plate that is wider than the press-fitting portion 61, and one end face of which is tapered. The press-fitting portion 61 and the regulating portion 62 are connected in series. That is, the diameter-expanding piece 6 has a shape obtained by bending the middle part of a substantially convex (or T-shaped) flat plate.

Then, as shown in FIGS. 7 and 8, the press-fitting portions 61 are sandwiched between the inner end edges of the tightening ring body 5 in a state where the expanded diameter piece 6 is press-fitted into the tightening ring body 5. At the same time, its end portion is provided so as to project inward in the radial direction of the tightening ring body 5, and the restriction portion 62 is provided so as to project outward in the axial center direction of the tightening ring body 5.

Specifically, the press-contact surface 61 of the press-fitting portion 61
The middle part of 1, 611 is sandwiched by the inner peripheral side end edges of both end faces 52, 53 of the tightening ring body 5, and the press-fitting part 61 can contact the tip end face of the pipe 1 to be inserted. So as to project inward in the radial direction of the tightening ring body 5, and the restriction portion 62 projects outward in the axial direction of the tightening ring body 5 such that one side of the tapered shape is the tip. .

Then, as shown in FIG. 1, the tightening ring body 5 and the expanded diameter piece 6 thus combined are fitted into the inside of the cover 14. In addition, a plurality of (for example, three) contact portions 15 ... Are provided in the inner peripheral surface of the cover 14 in the circumferential direction, and the tightening ring body 5
The end face of the contacting member abuts on the abutting portions 15 and prevents the tightening ring body 5 from moving unnecessarily inward in the axial direction.

At this time, the tightening ring 5 is movable in the inside of the cover 14 in the axial direction by a minute distance (for example, about 1 mm) between the contact portions 15 ... Diameter piece 6
Means that the restriction portion 62 (longer than the minute distance) is attached to the tightening ring 5
Since it is arranged so as to project from the end surface of the fastening ring body 5, when the tightening ring body 5 is fitted into the cover 14, the diameter of the contact ring 15 and the end surface of the tightening ring body 5 are expanded. It is possible to prevent the piece 6 (regulating portion 62) from being caught, and therefore, the expanded diameter piece 6 can be reliably separated from the tightening ring body 5.

Then, when the pipe 1 is inserted in the direction of arrow A, as shown in FIG. 11 (A), the tip end surface of the pipe 1 presses the press-fitting portion 61 of the diameter expanding piece 6 to expand the diameter expanding piece. 6 is the regulation unit 62
The press-fitting portion 61 separates from the slit 51 while rotating (swinging) around the outer diameter side end portion s of the. The regulation unit 62
The outer diameter side end portion s of the pipe and the press-fitting portion where the tip portion of the pipe 1 abuts
A predetermined interval r is set between the contact portion p of 61 and the pipe 1 inserted so that a sufficient rotation moment can be applied to the expanded diameter piece 6 in the press-fitted state. The expansion piece 6 is easily removed from the slit 51.

When the pipe 1 is further inserted, as shown in FIG.
As shown in (B), the tip end of the restricting portion 62 abuts on the inner surface of the cover 14 at a contact point n, and the expanded diameter piece 6 is centered on the contact point n instead of the outer diameter side end s. By rotating, the press-fitting portion 61 is separated from the slit 51 as shown in FIG.
As shown in FIG. 2, the expanded diameter piece 6 separates from the tightening ring body 5 to bring the pipe 1 into the tightened connection state.

As described above, since the tip end surface of the pipe 1 presses the flat press-fitting portion 61, the tip end surface of the pipe 1 does not stick into the press-fitting portion 61 even when the pipe 1 is made of soft resin. Further, as shown in FIG. 7 (B), since the press-fitting portion 61 is sandwiched between the inner end edges of the tightening ring body 5, the diameter-expanding piece 6 is stable against the force from the circumferential direction. The holding posture can be maintained, and therefore, even when the pipe 1 is inserted while being rotated so as to be screwed in, the expanded diameter piece 6 does not separate from the tightening ring body 5. Further, as shown in FIG. 11 (B), the center of rotation (fulcrum) of the expanded diameter piece 6 is changed from the outer diameter side end portion s to the contact point n, so that the rotational moment can be increased and the weight is further reduced. The expanded diameter piece 6 can be reliably separated by force.

When the expanded diameter piece 6 separates from the slit 51, a snapping sound that can be confirmed from the outside is generated, and the expanded diameter piece 6 is placed in the escape space 16 as shown in FIG. Immediately after being discharged, the diameter of the tightening ring body 5 is reduced and the pipe 1 is tightened, and the inner surface of the pipe 1 is brought into close contact with the seal member 4 to be in a sealed state, and the outer peripheral surface of the pipe 1 is prevented from coming off. Hang on. In this way, the operator can clearly confirm that the tightening (insertion) of the pipe 1 has been completed by the sound of the expansion piece 6 coming off.

In the above-mentioned connected state, the pipe 1 is reduced in diameter by the tightening ring body 5 and bites into the insertion tube portion 3 (stepped portion 22), so that the pipe 1 is prevented from coming off from the joint body 2. In this state, the sealing member 4 ensures the sealing performance without interruption over the entire inner surface of the pipe 1, so that even if the pipe 1 has a variation in diameter or a dimensional change due to thermal deformation or the like. Always, it is possible to maintain excellent water stopping performance and to secure stable sealing performance for a long period of time. In this case, the cover 14
Since the connection portion of the pipe 1 is protected by this, there is an advantage that the durability is improved and the sealing property can be secured more stably for a long period of time.

Further, the connecting work is performed by simply pushing the pipe 1 into the joint body 2, without using a connecting tool or a fastening member, and without requiring any skill, it is very efficient, so-called. The connection work can be completed by one-touch operation, and the completion of the connection work is performed by the diameter expansion piece 6
Since it can be clearly confirmed from the outside by the detachment sound of, the workability at the site is significantly improved. Further, since the respective constituent members are integrally assembled in advance, the management of the parts becomes easy, and the on-site procurement becomes easy and reliable, and the risk of losing the parts is small.

Next, FIG. 12 shows the pipe 1 and the retaining ring 8 when a pulling force is generated in the pipe 1 after the connection is completed.
The action explanatory drawing with and is shown. That is, as shown in FIG. 12 (A), when the pipe 1 is pulled in the direction of coming out of the insertion tube portion 3, the end portion of the pipe 1 is narrowed (tightened) by the tightening ring body 5. Therefore, the end portion of the pipe 1 is difficult to move in the pulling direction due to the friction between the inner peripheral surface of the end portion of the pipe 1 and the outer peripheral surface of the insertion cylindrical portion 3 as the inner peripheral surface thereof is caught by the stepped portion 22 of the insertion cylindrical portion 3. Become.

Before the movement of the end of the pipe 1 occurs, the portion of the pipe 1 that is not fastened to the fastening ring body 5 in FIG. (Direction) The part of the pipe 1 on the left side begins to expand (due to the deformation), and as shown in FIG. 12B, the expansion of the pipe 1 causes the pipe 1 to be bent (at an angle) and come into contact with the pipe 1. The tooth portion 12 of the retaining ring 8 that follows the pipe 1 swings so that its bending becomes horizontal (raised in the direction in which the angle returns to its original position), as shown in FIG. 12 (C). Then, the cap nut 10 is rocked until it comes into contact with the wall surface of the inner flange portion.

Therefore, the tooth portion 12 of the retaining ring 8 narrows down the pipe 1 while rising in the direction in which the angle returns to its original position. Therefore, if a pulling force is applied to the pipe 1, a stronger tightening force acts. , Will be a strong retainer. In addition,
At this time, the inner peripheral side of the pipe 1 narrowed by the tooth portions 12 is hooked in the concave portion 21 on the outer peripheral surface of the insertion tubular portion 3,
The withdrawal of the pipe 1 is further prevented.

Also, the tooth portion 12 (as shown in FIGS. 3 and 4)
... are formed by notches (not punching), and the gap between adjacent tooth portions 12, 12 is set small,
Compared to the conventional retaining ring (shown in Fig. 14), tooth 12 ...
The contact surface pressure between the pipe 1 and the pipe 1 becomes large, the contact surface pressure becomes small, the biting of the teeth 12 on the outer peripheral surface of the pipe 1 is reduced, and the damage by the teeth 12 of the pipe 1 can be suppressed.
Accidents of cutting the pipe 1 can be prevented. Further, the load applied to the tooth portion 12 is reduced, and the reverse bending of the tooth portion 12 and the dropout of the pipe 1 by scraping the outer skin of the pipe 1 by the tooth portion 12 are suppressed.

The present invention is not limited to the above-described embodiment, and although not shown, the outer peripheral surface of the insertion tube portion 3 is formed with, for example, a plurality of tapered surfaces or circumferential step portions, It is also preferable to prevent the pipe 1 from coming off more reliably. In addition, an inner surface of the tightening ring body 5 may be formed with a retaining hook portion such as a knurled concave-convex shape or a tapered shape that locks the outer peripheral surface of the pipe 1. Further, the tightening ring body 5, the expanding piece 6,
The shape of the retaining ring 8 can be changed in design without departing from the scope of the present invention.

[0038]

Since the present invention is configured as described above, it has the following effects.

On the inner peripheral side of the retaining ring 8 (according to claim 1), a plurality of tooth portions 12 formed by cutting at equal intervals in the circumferential direction are provided. 12,
The gap between the teeth 12 can be set to be small, the contact area between the teeth 12 ... And the pipe 1 is increased, the teeth 12 are hooked over the entire circumferential direction of the pipe 1, and the retaining is further strengthened. Also, tooth 12
The contact surface pressure between the pipe 1 and the tooth 1 is reduced, the biting of the tooth portion 12 on the outer peripheral surface of the pipe 1 is reduced, and the tooth portion 12 of the pipe 1 is reduced.
It is possible to suppress the damage due to, and prevent the accident of cutting the pipe 1. Further, the load applied to the tooth portion 12 is reduced, and the reverse bending of the tooth portion 12 and the dropout of the pipe 1 by scraping the outer skin of the pipe 1 by the tooth portion 12 are suppressed. In this way, with a simple structure, stronger retaining of the pipe 1 is prevented .

Further, the one-touch operation of pushing the pipe 1, diameter-expansion piece 6, with detached from the slit 51 of the clamping ring body 5, the ring body 5 tightening is reduced in diameter, fastening the ends of the pipe 1 The inner surface of the pipe 1 comes into close contact with the seal member 4 to be in a sealed state, and the connection work can be completed.

In the connected state, the inner surface of the pipe 1 is kept in a sealed state by the sealing member 4, so that even if the diameter of the pipe 1 is changed or the dimension is changed due to thermal deformation, the water is always excellent. The performance can be maintained and stable sealing property can be maintained for a long period of time.

The connecting work can be accomplished simply by pushing in the pipe 1, without using a connecting tool or a fastening member, and without requiring skill, so that the connecting work can be completed by a so-called one-touch operation. The workability at the site is significantly improved. Further, since the respective constituent members are integrally assembled in advance, the management of the parts is facilitated, the on-site procurement is facilitated and reliable, and the risk of the parts being lost is small.

On the outer peripheral surface of the insertion tube portion 3 (according to claim 2 ), a portion corresponding to the tooth portions 12 of the retaining ring 8 is provided,
Since the concave portion 21 is provided, the pipe 1 tightened by the tooth portions 12 can be hooked in the concave portion 21, so that the pipe 1 is more firmly prevented from coming off.

[Brief description of drawings]

FIG. 1 is a front sectional view showing an embodiment of a pipe joint of the present invention.

FIG. 2 is a front cross-sectional view of a pipe inserted into a pipe joint.

3A and 3B are a side view and a front sectional view of a retaining ring during formation.

FIG. 4 is a side sectional view of a retaining ring.

FIG. 5 is a side view of a tightening ring body and an enlarged view of a main part.

FIG. 6 is a sectional view taken along line XX of FIG.

FIG. 7 is a side view and an enlarged view of a main part of the tightening ring body in a state where the expanded diameter piece is press-fitted.

8 is a cross-sectional view taken along the line YY of FIG. 7 (A).

FIG. 9 is a perspective view of a diameter expansion piece.

FIG. 10 is a front view and a side view of the expanded diameter piece.

FIG. 11 is an explanatory view of the action of the expanded diameter piece and the pipe.

FIG. 12 is an explanatory view of the action of the retaining ring and the pipe.

FIG. 13 is an exploded view of a conventional pipe joint.

FIG. 14 is a side view of a conventional retaining ring.

[Explanation of symbols]

1 pipe 2 Joint body 3 Insert tube 4 Seal member 5 Tightening ring 6 Expanding piece 7 concave groove 8 retaining ring 12 teeth 21 recess 51 slits

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akio Yasuda 8-22 Kikusuicho, Kawachinagano-shi, Osaka Prefecture Higashio Mech Co., Ltd. (56) References JP 10-19176 (JP, A) JP H 7-224978 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16L 21/08 F16L 19/08

Claims (2)

(57) [Claims] 1. A joint body 2 having an insertion tube portion 3 to be inserted into an end portion of a pipe 1 to be connected, and a recess of the insertion tube portion 3.
The seal member 4 mounted in the circumferential groove 7 and the insertion tube portion 3
With the elastic tightening force on the outer end of the pipe 1
A tightening ring 5 with a slit 51 for tightening, and the tightening ring 5.
Enlarge the diameter of the tightening ring 5 against the elastic force of the ring 5.
Inserted by being detachably held by the end of the slit 51.
Expanding piece that comes into contact with the tip of the pipe 1 and is removed
6 and an insertion tube part to be inserted into the end part of the pipe 1 to be connected
3 and a retaining ring 8 that is retained by the inner peripheral side of the outer peripheral surface of the pipe 1 fitted onto the insertion tube portion 3 in a retaining state.
A plurality of tooth portions 12 formed by cutting at equal intervals in the circumferential direction are provided on the inner peripheral side of the pipe joint. 2. A retaining ring is provided on the outer peripheral surface of the insertion tube portion 3.
The concave portion 21 is provided in a portion corresponding to the tooth portion 12 of the gear 8.
The pipe joint according to claim 1 .