JP2569694Y2 - Pipe fittings - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a flexible tube for supplying fluid to a cylinder, a valve or the like.
The present invention relates to a pipe joint for connecting to a connection port of a valve or the like.

[0002]

2. Description of the Related Art A pipe joint of this type is disclosed in
No. 20947, Japanese Patent Publication No. 63-29156 and Japanese Utility Model Publication No. 1-7914, and a locking claw system disclosed in Japanese Utility Model Publication No. 57-45512 and Japanese Patent Publication No. 58-93.
No. 11, JP-B-61-10077 and JP-B-61-10712 are known.

In the lock claw method, an annular chuck having relatively strong rigidity and spring property is housed in a mounting recess of the joint body, and a plurality of lock claws at the tip of the chuck are inserted into the outer peripheral surface of the flexible tube. It has become. In the collet method, the outer peripheral bulge of the collet tip made of an elastic body abuts on the tapered portion of the retaining ring in the mounting recess of the joint body, and this abutting action causes the arm pieces on the collet tip side to move in the radial direction. Concentrated on the curve,
The claw pieces provided on the inner peripheral side of the arm piece enter into the outer peripheral surface of the flexible tube.

[0004]

However, in the lock claw method, since the flexible tube is held only by the lock claw, this holding must rely on the biting force of the lock claw. In order to securely hold the flexible tube, it is necessary to increase the biting force of the lock claw with respect to the flexible tube, but it is difficult to optimally set this biting force, and the biting force, that is, the flexible tube holding force, tends to be excessive. As a result, when the flexible tube is inserted into the chuck and the plurality of lock claws are expanded, the lock claws are strongly inserted into the flexible tube, and the leading end of the flexible tube reaches the innermost end of the mounting recess. May be considered.

[0005] In such an imperfect insertion state, the seal between the seal ring located further inside the chuck and the flexible tube is not formed, and fluid leakage occurs. In addition, since the tip of the flexible tube does not abut the innermost end of the mounting recess, the flexible tube is only supported by the locking claw. It will rock. Due to this swinging operation, the locking claw is further inserted into the flexible tube, which may cause a crack in the flexible tube or a breakage of the flexible tube.

Although the release of the lock claw is performed by pressing the release ring provided in the mounting concave portion against the chuck, the release of the lock claw is not easy because the locking claw has a large biting force. Especially,
The greater the diameter of the flexible tube, the greater the biting force of the lock claw, and the more difficult it is to make it difficult to release.

In the collet system, the smoothness of insertion and withdrawal of the flexible tube is much better than that of the lock claw system, but there is a drawback that the flexible tube has a small diameter and is easily pulled out. That is, in the pipe joint for a small-diameter flexible tube, the tapered area of the outer bulge at the tip of the collet becomes smaller, and the arm piece on the collet tip side due to the contact between the tapered portion of the retaining ring and the outer bulge. Becomes insufficiently concentrated. Therefore, the biting force of the claw pieces into the flexible tube is weakened.

The present invention eliminates the drawbacks of the lock claw method and the collet method and provides a pipe joint having the advantages of both methods. That is, it is possible to reliably seal the pressure fluid and securely grip the flexible tube. It is an object of the present invention to provide a pipe joint capable of performing the above.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, a mounting recess provided on the inlet side of a tubular joint body, an annular chuck inserted into the mounting recess, and an annular chuck are provided. And a release ring inserted before the annular chuck, and a cylindrical portion is provided at the base end of the annular chuck, and the annular chuck can be expanded and reduced in diameter. A slit is formed in the axial direction, and a bent reversal portion is provided on the distal end side of the annular chuck, which can be brought into contact with the distal end of the release ring. the diameter of the circle formed is set smaller than the outer diameter of the flexible tube, reduced diameter contouring working surface for reducing the diameter of the annular chuck abuts the inner peripheral portion of Installing with recesses on the tip side of the annular chuck Set , Together with the sealing ring provided for hydraulically transmitting portion for transmitting a fluid pressure acting in the withdrawal direction of the flexible tube to the annular chuck engaged with the cylindrical portion proximal end of the annular chuck, the tip of the seal ring
Is in contact with the peripheral surface of the cylindrical portion of the annular chuck.
The pipe joint was formed by providing a protrusion for positioning the seal on the seal ring .

[0010]

According to the above construction, when the flexible tube is inserted into the annular chuck, the diameter of the annular chuck slightly increases,
The claw part gets into the outer peripheral surface of the flexible tube. When the pressure is applied after the distal end of the flexible tube is inserted to the innermost end of the mounting recess, the seal ring and the flexible tube are moved in the pulling-out direction by the action of fluid pressure. At this time, the annular chuck is simultaneously moved based on the engagement between the fluid pressure action transmitting portion of the seal ring and the base end of the cylindrical portion of the annular chuck. Because of this engagement, the seal ring does not move relative to the annular chuck, and the distal end of the seal ring does not enter the back side of the distal end of the annular chuck.

The movement of the seal ring and the annular chuck causes the distal end portion of the annular chuck to abut against the diameter reducing working surface, and the abutting action causes the annular chuck to reduce the diameter. At this time,
Since the distal end of the seal ring does not enter the rear side of the distal end of the annular chuck, the diameter of the annular chuck is not hindered by the distal end of the seal ring. Therefore, the claw portion is not easily inserted into the outer peripheral surface of the flexible tube, and the flexible tube is prevented from coming off.

An annular chuck is provided at the end of the seal ring.
The annular chuck is in contact with the peripheral surface of the cylindrical part of the seal ring.
Since the protrusion for positioning is provided on the upper side, the annular chuck is accurately positioned in the mounting concave portion, and the entire distal end portion of the annular chuck is evenly brought into contact with the working surface for diameter reduction. Therefore, when the diameter of the annular chuck is reduced, the claw portion is hardly evenly inserted over the entire circumference of the flexible tube. What
In addition, a ring in which the protrusion contacts the inner peripheral surface of the cylindrical portion of the annular chuck.
If it is configured with a ridge, the position of the annular chuck is determined.
Accuracy is further improved.

An inner peripheral portion of the seal ring is provided with a tapered pot-like taper extending to the inner side of the mounting recess, and an outer peripheral portion of the seal ring is formed in a cylindrical side surface closely contacting the inner wall of the mounting recess. It is preferable that the lower half of the seal ring be formed in a semicircular cross section. According to this configuration, the pressure fluid can be evenly received by the entire lower half portion of the seal ring, and the contact portion between the mounting concave portion of the joint body and the outer peripheral portion of the seal ring, and the inner peripheral portion of the seal ring and the flexible tube Is uniformly sealed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will now be described with reference to FIGS.
A description will be given based on FIG. As shown in FIG. 1, a guide ring 3 is non-slidably fitted in an inner periphery of an opening of a mounting recess 2 on an inlet side of a cylindrical joint body 1 screwed to a connection port of a cylinder, a valve, or the like. A tapered working surface 3a is formed on the inner periphery of the inner end of the guide ring 3.
A release ring 4 is inserted into the guide ring 3 so that it cannot be pulled out, and the inner diameter of the release ring 4 is set slightly larger than the outer diameter of the flexible tube 7.

The mounting recess 2 is divided into a small-diameter portion 2b and a large-diameter portion 2c between the innermost end 2a and the mounting position of the guide ring 3, and the inner diameter of the small-diameter portion 2b is larger than the outer diameter of the flexible tube 7. Is also set slightly larger. An annular seal ring 5 is fitted into the large diameter portion 2c,
An annular chuck 6 having elasticity is mounted on the seal ring 5.

As shown in FIGS. 1 and 2, the annular chuck 6 has a cylindrical portion 6e at the base end thereof. The distal end side of the annular chuck 6 extends toward the entrance side of the mounting recess 2 and the side of the axis L and then bends and turns to the back side, and the upper surface of this bent portion has an upwardly acting surface 6a and a downwardly inclined surface 6a. It forms an annular actuated convex surface composed of the actuated surface 6b. At the tip of the annular chuck 6, a plurality of claw portions 6c are provided on the working surface 6b.
The radius of the circle formed by the tip edges of the claw portions 6c is set slightly smaller than the outer diameter of the flexible tube 7 in the free state of FIG. The annular chuck 6 is provided with a slit 6d extending from the base end to the distal end along the axis L, so that the diameter of the annular chuck 6 can be increased or reduced.

As shown in FIGS. 1 and 3, the lower half of the seal ring 5 is formed in a semicircular cross section, and its outer peripheral surface is a curved surface 5e. A taper 5c is provided in an inner periphery of the upper half portion of the seal ring 5 in a shape of a pick-up pot. An annular ridge 5a is provided on the upper end of the seal ring 5, and a step 5b is formed on the outer peripheral side of the base. Seal ring 5
Is set such that its upper half outer peripheral surface 5d is in close contact with the inner wall of the large diameter portion 2c of the mounting recess 2. The diameter of the circle formed by the distal end edge 5f of the taper 5c is set slightly smaller than the outer diameter of the flexible tube 7.

In the state shown in FIG. 1, the curved surface 5e of the seal ring 5 is in contact with the lower end surface 2d of the large diameter portion 2c of the mounting recess 2. When the annular chuck 6 is mounted on the seal ring 5, the lower end of the cylindrical portion 6e is in contact with the step 5b, and the inner peripheral surface of the cylindrical portion 6e is the outer peripheral surface of the annular ridge 5a. Is lightly abutted. Next, the operation of the present embodiment will be described.

As shown in FIG. 4, when the flexible tube 7 is inserted into the release ring 4 and pushed in, the distal end of the flexible tube 7 comes into contact with the downwardly-sloped working surface 6b of the annular chuck 6, and the flexible tube 7 is pushed in. The action causes the annular chuck 6 to expand. At this time, since the base end of the cylindrical portion 6e of the annular chuck 6 can slide on the step 5b, the annular chuck 6 is smoothly expanded.

When the flexible tube 7 is further pushed in, the flexible tube 7 passes through the distal end edge 5f of the seal ring 5 while keeping the seal ring 5 in close contact. Then, the distal end of the flexible tube 7 fits into the small diameter portion 2b, and the distal end abuts on the innermost end 2a. In this state, the claw portion 6c of the expanded annular chuck 6 slightly bites into the outer peripheral surface of the flexible tube 7 by the elastic deformation action of the annular chuck 6.

That is, the biting force on the flexible tube 7 in the state shown in FIG. 4 is only due to the elastic deformation of the annular chuck 6, and the diameter of the circle formed by the tip edges of the plurality of claw portions 6c and the annular chuck 6 By appropriately setting the elastic force, the biting force on the flexible tube 7 can be set properly and easily.
Therefore, the flexible tube 7 is smoothly inserted into the joint body 1, and the leading end of the flexible tube 7 reaches the innermost end 2a without fail.

When the pressurized fluid is supplied in the state of FIG. 4, the curved surface 5e of the seal ring 5 receives the pressurized fluid as shown in FIG. 5, and the tightness of the seal ring 5 to the flexible tube 7 and the mounting recess 2 is improved. Better. This prevents the fluid from leaking from the mounting recess 2, and the inside of the mounting recess 2 is in a pressurized state. Due to this pressurizing action, the seal ring 5 and the flexible tube 7 are lifted and moved in the pulling-out direction. At this time, the step portion 5b and the cylindrical portion 6
Since the seal ring 5 pushes up the annular chuck 6 based on the engagement with e, the annular chuck 6 also moves upward together with the seal ring 5 and the flexible tube 7.

Here, a comparison will be made between this embodiment and a configuration in which the seal ring 5 is not provided with the stepped portion 5b and the annular chuck 6 is supported at the tip of the annular ridge 5a.
In any of the configurations, when the flexible tube 7 is inserted into the seal ring 5, the sliding contact between the two causes the leading edge 5f of the seal ring 5 to be pulled downward, and this pulling causes the annular ridge 5a to bend inward. Works.

Even when the stepped portion 5b is not provided on the seal ring, the cylindrical portion 6e of the annular chuck 6 and the annular ridge 5
The annular chuck 6 and the seal ring 5 are integrally moved by frictional contact with the annular chuck 6. When the upwardly-inclined affected surface 6 a of the annular chuck 6 comes into contact with the operating surface 3 a of the guide ring 3, the annular chuck 6 There is a possibility that the annular ridge 5a bent inward may enter the uppermost portion on the back side of the affected surface 6a with the upward slope. In such a case, the annular ridge 5a presses the actuated surface 6a outward, thereby inhibiting the diameter reduction of the annular chuck 6. On the other hand, according to the configuration of the present embodiment, there is no room for the annular ridge 5a to reach the back side of the affected surface 6a, and the above-described adverse effects do not occur.

Now, the seal ring 5 and the annular chuck 6
With the upward movement, the ascending affected surface 6a of the annular chuck 6
Abuts against the working surface 3a of the guide ring 3. Then, the pressure fluid presses the annular chuck 6 against the working surface 3a via the seal ring 5, and as the annular chuck 6 is further moved upward, the diameter of the annular chuck 6 is reduced. Then, the claw portion 6c
Is further inserted into the outer peripheral surface of the flexible tube 7, and the flexible tube 7 is securely held by the annular chuck 6. According to this configuration, the annular protrusion 5a does not hinder the diameter reduction of the annular chuck 6, and the flexible tube 7 is securely held.

According to the present embodiment, when the seal ring 5 and the annular chuck 6 move upward and the upwardly-inclined working surface 6a comes into contact with the working surface 3a, the base end of the cylindrical portion 6e of the annular chuck 6 is stepped. The outer peripheral edge of the seal ring 5 is momentarily pressed through the portion 5b. At this time, since the lower half of the seal ring 5 is formed in a semicircular cross section and is uniformly pressed, the seal ring 5 is pulled downward by the flexible tube 7 with the base end of the cylindrical portion 6e as a fulcrum. The bending of the inner peripheral portion can be eliminated, and the posture can be adjusted. Thereby, the sealing properties at the contact portion between the outer peripheral surface 5d of the seal ring 5 and the inner wall of the mounting recess 2 and the contact portion between the inner peripheral portion of the seal ring 5 and the flexible tube 7 are equalized, and the sealing property is locally improved. Is prevented from remaining.

The claw portion 6c further penetrates the outer peripheral surface of the flexible tube 7 due to the diameter reduction of the annular chuck 6, but this penetration stops when both formed ends sandwiching the slit 6d come into contact. Therefore, by setting the width of the slit 6d of the annular chuck 6 in the free state in FIG. 1 to an appropriate value, it is possible to prevent the claw portion 6c from being dug into the flexible tube 7 more than necessary. Thereby, the flexible tube 7 can be strongly gripped and prevented from coming off while preventing the flexible tube 7 from being damaged due to excessive biting. Also, since the diameter of the annular chuck 6 is reduced by direct contact between the annular chuck 6 and the guide ring 3, the claw portion 6 c engages the flexible tube 7 even when the diameter of the flexible tube 7 is small. The penetration force of 6c is sufficiently obtained.

The downwardly-sloping annular actuated surface 6b and the peripheral edge of the distal end of the flexible tube 7 are displaced in the radial direction.
That is, assuming that the axis of the annular chuck 6 is deviated from the axis L of the mounting concave portion 2, when the flexible tube 7 is inserted, the peripheral edge of the distal end of the flexible tube 7 abuts against the acting surface 6b. Such a contact acts as an action of inclining the annular chuck 6, and if the annular chuck 6 is inclined, only a part of the plurality of claw portions 6c becomes difficult to enter into the flexible tube 7. If pressure is applied in such a state of being partially entangled, the working surface 3a for diameter reduction and the working surface 6a having an upward slope come into contact with each other, and the working surface 6a
No uniform diameter reduction action occurs over the entire circumference of a.

In such a state, the biting force of the claw portion 6c into the flexible tube 7 becomes weak. However, in the free state before the insertion of the flexible tube 7 shown in FIG. The axis of the annular chuck 6 coincides with the axis L of the mounting recess 2 because it is fitted on the outer peripheral surface of the annular ridge 5 a. As a result, the working surface 6b of the annular chuck 6 and the peripheral edge of the distal end of the flexible tube 7 abut evenly over the entire circumference, and the annular chuck 6 is uniformly expanded from the axis L over the entire circumference without tilting. Therefore, the working surface 3a in the pressurized state
And the affected surface 6a do not hit each other, and a uniform diameter reduction is performed over the entire circumference of the affected surface 6a. Thereby, the plurality of claw portions 6c can be hardly evenly inserted into the flexible tube 7.

When the flexible tube 7 is to be removed from the pipe joint, the release ring 4 is pushed in so that the tip of the release ring 4 comes into contact with the downwardly inclined surface 6b of the annular chuck 6, and the annular chuck 6 is expanded. Thereby, the biting of the claw portion 6c into the flexible tube 7 is released, and the flexible tube 7 can be pulled out from the joint body 1.

The present invention is not limited to the above embodiment, but can be implemented in the following modes. That is, (1) as shown in FIG. 6, the distal end side of the annular chuck 8 is curved and inverted, and the lengths of the plurality of slits 8a and the claw portions 8b are set from the distal end to near the proximal end of the cylindrical portion 8c. thing. (2) As shown in FIG. 7, the distal end of the annular chuck 9 is suddenly bent and turned to the back side to form a downwardly inclined working surface 9b, and the bent end 9a of the annular chuck 9 is
The diameter of the annular chuck 9 is reduced by bringing the annular chuck 9 into contact with the working surface 10a. (3) As shown in FIG. 8, the cylindrical portion 1 of the annular chuck 11
1e, a flange portion 11f is provided at the base end, and the flange portion 11f is provided.
Is set equal to or less than the large diameter portion 2c of the mounting recess 2. (4) As shown in FIG.
2c is formed to extend from the uppermost end of the annular ridge 12a.

[0032]

As described above in detail, according to the present invention, the annular chuck seals based on the engagement between the fluid pressure action transmitting portion of the seal ring and the cylindrical end of the annular chuck at the time of supplying the pressurized fluid. Since the tip of the seal ring is moved together with the ring so that the tip of the seal ring does not enter the rear side of the tip of the annular chuck, the tip of the seal ring does not hinder the diameter reduction of the annular chuck. Moreover, the seal ring
The tip of the ring is in contact with the peripheral surface of the cylindrical part of the
Providing a protrusion to position the chuck on the seal ring
So that the annular chuck is accurate within the mounting recess
And the entire tip of the annular chuck is
The chuck is evenly contacted with the
Claw is evenly distributed over the entire circumference of the flexible tube.
Dig into. Therefore, an excellent effect is obtained that the pressurized fluid can be reliably sealed, and the flexible tube can be securely gripped by making the claw portion of the annular chuck hardly fit into the flexible tube.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a state before inserting a flexible tube according to an embodiment of the present invention.

FIG. 2 is a perspective view of an annular chuck.

FIG. 3 is a plan view of a seal ring.

FIG. 4 is a longitudinal sectional view showing a state after insertion of a flexible tube and before pressurization.

FIG. 5 is a longitudinal sectional view showing a state after pressurization after insertion of a flexible tube.

FIG. 6 is a perspective view showing another example of the annular chuck.

FIG. 7 is a vertical sectional view of a main part showing another example of the present invention.

FIG. 8 is a vertical sectional view of a main part showing another example of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Joint main body, 2 Mounting recess, 3a Working surface as working surface for reducing diameter, 4 release ring, 5 seal ring, 5
b Step portion as fluid pressure action transmitting portion, 6 annular chuck, 6b acted surface as bending reversal portion, 6c claw portion,
6d slit, 6e tubular part, 7 flexible tube, L axis.

Claims (3)

(57) [Scope of request for utility model registration] An attachment recess (2) provided on the inlet side of a tubular joint body (1), an annular chuck (6) inserted into the attachment recess (2), and an annular chuck (6).
And a release ring (4) inserted before the annular chuck (6). A cylindrical portion (5) is provided at the base end of the annular chuck (6). 6e), and a slit (6d) that allows the annular chuck (6) to expand and contract in diameter is provided in the direction of the axis (L), and a distal end of the annular chuck (6) is provided with a distal end of a release ring (4). A bendable reversal part (6b) that can be contacted is provided,
A claw (6c) is provided at the tip of b), and the diameter of a circle formed by the tip edge of the claw (6c) is set smaller than the outer diameter of the flexible tube (7). An inner peripheral portion of the annular chuck (6) is provided with a diameter reducing action surface (3a) for reducing the diameter of the annular chuck (6) by contacting the distal end side of the annular chuck (6). A fluid pressure action transmission part (5b) for engaging with the base end of the cylindrical part (6e) of (6) and transmitting the fluid pressure action in the drawing direction of the flexible tube (7) to the annular chuck (6). When you set
And an annular chuck at the end of the seal ring (5).
(6) The annular chuck is in contact with the peripheral surface of the cylindrical portion (6e).
Projection (5) for positioning (6) on seal ring (5)
A pipe joint characterized by comprising a) . 2. The projection (5a) is connected to the cylindrical portion (6e).
The pipe joint according to claim 1, wherein the pipe joint is constituted by an annular ridge (5a) in contact with an inner peripheral surface of the pipe joint. 3. An inner peripheral portion of the seal ring (5) is provided with a tapered pot-like taper (5c) extending to the inner side of the mounting recess (2), and an outer peripheral portion (5b) of the seal ring (5). )
The pipe according to claim 1 or 2, wherein the seal ring (5) is formed to have a semicircular cross-sectional shape, and the seal ring (5) is formed to have a semicircular cross section. Fittings.