JPH073276B2 - Tube fittings - Google Patents

Description

TECHNICAL FIELD The present invention relates to a tube joint, and more specifically to a tube joint suitable as a joint for synthetic resin, particularly fluororesin tubes.

[Prior Art] As a tube joint of this type, a conventional tube joint, for example, Japanese Utility Model Laid-Open No. 62-52
Some are described in Japanese Patent No. 391.

This prior art is a trapezoidal seal ring that fits in a joint body, a cap nut for mounting a hard pipe made of synthetic resin to the joint body, and a taper hole communicating with a through hole for pipe insertion of the joint body. And a trapezoidal tapered ring with a wide inclined split groove that fits in a tapered hole communicating with the female thread of the cap nut, deforms the outer circumference of the pipe by applying compressive force in the direction of its center to the pipe. It is a pipe joint characterized in that it is adapted to be fixed.

[Problems to be Solved by the Invention] The above-mentioned conventional technique measures a seal and a retainer by inserting a taper ring or a seal ring into the tube, but since there is no insert in the tube, There was a problem that the biting was weak, the tube could easily come out of the joint body, and the sealing property changed with temperature cycles, so-called "re-tightening" was required and maintenance was troublesome.

According to the present invention, in order to eliminate the above-mentioned problems, a large diameter portion preliminarily formed on the tube is inserted into the relay cylinder up to the surface of the flange, and the relay ring sandwiches the large diameter portion. The groove ring formed on the outer peripheral surface of the protruding ring of the relay cylinder and the inner surface of the relay ring at the intermediate portion of the large diameter portion by tightly press-fitting against the elasticity of each material of the tube, the relay cylinder, and the relay ring. It is an object of the present invention to provide a tube joint in which a tube diffractive portion tightly sandwiched between the inner peripheral surface of the tube joint and the inner surface of the tube joint is formed.

[Means for Solving the Problems] The above-described object of the present invention is to use a plastic such as a fluororesin in constructing a tube joint in which a deformed portion is formed at the time of attachment of the tube to prevent the tube from coming off. A large-diameter portion is formed at the end of the produced tube, and a relay cylinder having a protruding ring formed in the large-diameter portion is inserted up to the surface of the flange, and a relay ring having a groove ring loosely inserted in the tube is formed. The intermediate portion of the large diameter portion of the tube is connected to the outer peripheral surface of the protruding ring of the relay cylinder and the relay by pressing the large diameter portion against the outer peripheral surface of the relay cylinder against the elastic drag of these materials. The tube bent portion is formed by tightly sandwiching it with the inner peripheral surface of the groove ring of the ring, and the cap nut inserted through the tube is inserted into the male screw part of the joint body by the female screw part of the cap nut. Within the shoulder This is achieved by holding the tube tightly bent against the end face of the relay ring at the surface.

[Operation] After the preliminarily relay ring and the cap nut are inserted in the tube in order, the large diameter portion preliminarily formed in the tube is inserted into the relay cylinder up to the surface of the flange, and the relay ring is The outer diameter of the protruding ring of the relay cylinder is relayed to the intermediate portion of the large diameter part by tightly press-fitting against the elasticity of each material of the tube, relay cylinder or relay ring with the large diameter part sandwiched between them. It is possible to form a tube bending portion that is tightly sandwiched with the inner peripheral surface of the groove ring formed on the inner surface of the ring.

Since the tube bending portion is tightly held by the corner portion of the projecting ring and the corner portion of the groove ring, the tube is kept liquid-tight with respect to the relay cylinder and does not come out of the relay cylinder.

Further, by press-fitting the annular projection formed on the end surface of the relay cylinder into the annular groove formed on the end surface of the joint body, the relay cylinder and the joint body are held in a liquid-tight manner, and centering of both can be easily performed. .

Furthermore, by holding the middle part of the tube protruding from the end surface of the relay tube to the above end surface by bending and holding the inner surface of the shoulder portion of the cap nut firmly, the tube and the relay tube and relay ring can be pulled out from the joint body. Absent.

[Examples] Examples will be described with reference to the drawings.

First, the basic constitution of the present invention is to construct a tube joint in which a deformed portion is formed at the time of mounting the tube to prevent the tube from coming off, and a tube made of a plastic such as fluororesin as shown in FIG. 2 and 3 by using a heat forming jig a as shown in FIG.
A large diameter portion 2 as shown in the figure is formed.

Then, the relay cylinder 4 formed of fluororesin as shown in FIG. 4 in which the protrusion 3 is formed in the large diameter portion 2 is inserted up to the surface of the flange 5.

Further, the relay ring 6 loosely inserted in the tube 1 as shown in FIG. 4 is moved downward by using the lowering jig b, and after the state shown in FIG. 2 is sandwiched between the outer peripheral surface of the relay cylinder 4 and the surface of the flange 5 by press fitting.

By this press fitting, the intermediate portion of the large diameter portion 2 of the tube 1 and the outer peripheral surface of the protruding ring 3 of the relay cylinder 4 and the relay ring 6 are formed.
The tube bending portion 8 as shown in FIG. 6 is formed by being tightly sandwiched with the inner peripheral surface of the groove ring 7.

Further, the annular projection 9 formed on the end surface of the relay cylinder 4 is press-fitted into the annular groove 11 formed on the end surface of the joint body 10 so that the through hole 12 of the joint body 10 and the tube 1 are coaxially arranged. As shown in FIG. 7, the cap nut 14 previously inserted into the tube 1 is screwed into the male screw portion 13 of the joint body 10 with the female screw portion 15 thereof, and the inner surface of the shoulder portion 16 of the cap nut 14 is adjusted as shown in FIG. The tube joint according to the present invention is constituted by holding 1 at the end face of the relay ring 6 by bending and holding it tightly.

Either one of the relay cylinder 4 and the relay ring 6 may be made of plastic such as fluororesin and the other may be made of metal. However, when the joint body 10 is made of metal, the relay cylinder 4 is made of plastic such as fluororesin. Make with.

The annular projection 9 and the joint body 10 of the relay cylinder 4 shown in FIG.
The liquid-tightness is also maintained by omitting the respective annular grooves 11 and strongly pressing the lower surface of the flange 5 of the relay cylinder 4 and the upper surface of the joint body 10 against each other as shown in FIG.

FIG. 9 shows another embodiment of the present invention, which has an embedding recess 10a for embedding the relay cylinder 4 and the relay ring 6 in place of the annular groove 11 of the joint body 10 of the above embodiment. While making the joint body 10, the flange 5 and the annular projection 9 of the relay cylinder 4 are removed to form a ring-shaped relay cylinder 4, and the relay cylinder 4 and the relay ring 6 are embedded in the hook portion 6a of the recessed portion 10a. It is a tube joint that is tightly press-fitted into the hook-shaped recess of.

In FIG. 8 and FIG. 9, the same reference numerals as those in the above-mentioned embodiment show the same effect portions, respectively.

The configuration of the present invention is as described above. Next, the usage state and operation of the tube joint according to the present invention will be described below.

First, as shown in FIG. 6, the preliminary relay ring 6 and the cap nut 14 are sequentially inserted into the tube 1 and then preformed on the tube 1 by the heat molding jig a as shown in FIG. The large diameter portion 2 is inserted into the relay cylinder 4 up to the surface of the flange 5 as shown in FIG.

Then, as shown in FIG. 5, the relay ring 6 is tightly press-fitted against the elasticity of each material of the tube 1, the relay cylinder 4 or the relay ring 6 in the relay cylinder 4 with the large diameter portion 2 interposed therebetween. A tube tightly sandwiched between the outer peripheral surface of the protruding ring 3 of the relay cylinder 4 and the inner peripheral surface of the groove ring 7 formed on the inner surface of the relay ring 6, as shown in FIG. The bending portion 8 can be formed as shown in FIG.

Since the tube bending portion 8 is tightly held by the corner portion of the groove ring 7 and the corner portion of the protruding ring 3 as shown in FIG.
The tube 1 is kept liquid-tight with respect to the relay cylinder 4, and does not come out of the relay cylinder 4.

Further, the annular projection 9 formed on the end face of the relay cylinder 4 is press-fitted into the annular groove 11 formed on the end face of the joint body 10 as shown in FIG. 7, so that the relay cylinder 4 and the joint body 10 are kept liquid-tight. At the same time, centering of both can be easily performed.

Further, as shown in FIG. 7, the intermediate portion of the tube 1 protruding outside from the end surface of the relay cylinder 4 is firmly bent and held by the inner surface of the shoulder portion 16 of the cap nut 14 on the end surface as shown in FIG. The relay cylinder 4 and the relay ring 6 do not come out of the joint body 10.

In the example of FIG. 9, the outer peripheral surface of the relay ring 6 is the joint body 10
Since the hook 6a and the hook-shaped recess are tightly inserted into the recess 10a, even if the cap nut 14 is omitted, the tube 1 including the relay ring 6 and the relay cylinder 4 can slip out of the recess 10a. There is no.

If the relay ring 6 is made of a fluororesin, its heat deformability is positively utilized to heat the relay ring 6 to the diameter of the tube large diameter portion 2 or an inner diameter slightly larger than this diameter. The diameter of the relay ring 6 is increased in advance by inserting the relay ring 6 into the tube 1, and the large diameter portion 2 of the tube is sandwiched to face the projecting ring 3. Then, the relay ring 6 is reheated to reduce the diameter. For example, as shown in FIG. 6, the tube 1 can be clamped tightly and pressed onto the outer peripheral surface of the projecting ring 3.

Particularly in this case, since it is not necessary to forcefully press the relay ring 6 mechanically and physically as in the above-described embodiment, the press-fitting work can be performed more easily.

[Effects of the Invention] Since the present invention is configured as described above, it has the effects described below.

After inserting the preliminarily relay ring 6 and the cap nut 14 into the tube 1 in order, the large diameter portion 2 preliminarily formed in the tube 1 is inserted into the relay cylinder 4 up to the surface of the flange 5 thereof, The relay ring 6 is tightly press-fitted against the resilience of each material of the tube 1, the relay cylinder 4 or the relay ring 6 in the relay cylinder 4 with the large diameter portion 2 interposed therebetween, or the relay ring 6 is expanded by preheating. By inserting the relay ring 6 and then reheating it to reduce its diameter, the large diameter portion 2 can be tightly sandwiched and press-fitted into the relay cylinder 4.

Therefore, in the middle portion of the large diameter portion 2, a tube bending portion 8 tightly sandwiched by the outer peripheral surface of the protruding ring 3 of the relay cylinder 4 and the inner peripheral surface of the groove ring 7 formed on the inner surface of the relay ring 6 is formed. be able to.

The tube bending portion 8 is tightly held by the corner portion of the groove ring 7 and the corner portion of the projecting ring 3, so that the tube 1 is kept liquid-tight with respect to the relay cylinder 4 and comes out of the relay cylinder 4. Therefore, the sealing performance and pull-out strength are not impaired by the temperature cycle and aging, so-called "reinforcement"
Since it is unnecessary, maintenance is easy, and the first effect is that the tube made of hard synthetic resin does not easily come off.

Further, the intermediate portion of the tube 1 protruding from the end face of the relay cylinder 4 is bent and held by the inner face of the shoulder portion 16 of the cap nut 14 firmly to the above end face, so that the tube 1 and the relay barrel 4 start.
The relay ring 6 does not come out from the joint body 10,
The second effect is that the function as a joint can be stably maintained for a long period of time.

Further, according to the second aspect, the annular projection 9 formed on the end face of the relay cylinder 4 is press-fitted into the annular groove 11 formed on the end face of the joint body 10, whereby the relay cylinder 4 and the joint body 10 are kept liquid-tight. At the same time, centering of both is easily performed, workability is good, and liquid leakage does not occur, which has a second effect.

According to claim 3, since the relay cylinder 4 and the relay ring 6 in which the tube 1 is tightly sandwiched are press-fitted in the recess 10a of the joint body 10, the length of the joint portion can be shortened in addition to the above effects. In addition to that, the cap nut 14 can be omitted.

[Brief description of drawings]

Each of the figures shows one embodiment of the present invention. FIG. 1 is a cross-sectional view of a tube and a thermoforming jig, and FIG. 2 is a tube press-fitted into the thermoforming jig to form a large diameter portion. Cross section,
3 and 4 are cross-sectional views showing the procedure for inserting the tube into the relay cylinder, FIG. 5 is a cross-sectional view showing the state at the moment when the relay ring is press-fitted into the relay cylinder with the tube sandwiched, and FIG. FIG. 7 is a sectional view of the tube joint disassembled, FIG. 7 is a sectional view of the tube joint, FIG. 8 is a sectional view of an essential part of the same, and FIG. 9 is a sectional view showing another example of the tube joint. 1 ... Tube, 2 ... Large diameter part, 3 ... Projection ring, 4 ... Relay tube, 5 ... Flange, 6 ... Relay ring, 7 ... Groove ring, 8 ... Tube bending part, 9 ... … Annular protrusion, 10 …… Joint body, 11 …… Annular groove, 12 …… Through hole, 13 …… Male screw part,
14 …… Cap nut, 15 …… Female thread, 16 …… Shoulder

Claims (3)

[Claims] 1. A tube joint in which a deformed portion is formed at the time of attachment of a tube to prevent the tube from coming off, and a large diameter portion 2 is formed at an end of a tube 1 made of plastic such as fluororesin. A groove ring made of fluororesin or the like which has a protruding ring 3 in the large diameter portion 2 and is inserted into the tube 1 by inserting a relay cylinder 4 made of fluororesin or the like up to the surface of the flange 5. The intermediate ring of the large diameter portion 2 of the tube 1 is fitted to the outer circumference of the protruding ring 3 of the relay cylinder 4 by press-fitting the relay ring 6 having the large diameter portion 2 on the outer peripheral surface of the relay cylinder 4. The surface and the inner peripheral surface of the groove ring 7 of the relay ring 6 are tightly sandwiched to form the tube bending portion 8, and the male screw portion 13 of the joint body 10 is preliminarily fitted with the cap nut 14 inserted into the tube 1. The internal thread 15 is screwed into the shoulder 16 of the cap nut 14 Tube Fittings formed by tightly refractive holding the tube 1 in terms to the end face of the relay ring 6. 2. An annular projection 9 formed on the end surface of the relay cylinder 4.
The tube joint according to claim 1, wherein the through hole 12 of the joint body 10 and the tube 1 are coaxially arranged by press-fitting into the annular groove 11 formed at the end of the joint body 10. 3. An embedded recess 10a provided at the end of the joint body 10.
The tube joint according to claim 1 or 2, wherein the relay cylinder 4 and the relay ring 6 with the tube 1 sandwiched therein are press-fitted and embedded.