JPH073277B2 - Tube fittings - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tube joint, and more particularly to a tube joint which is suitable as a joint for synthetic resin, particularly fluororesin tubes and which does not use a cap nut.

[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 taper ring provided with a wide inclined split groove that fits into a taper hole communicating with the female thread portion of the cap nut, deforms the outer circumference of the pipe by applying a compressive force in the center direction to the pipe. It is a pipe joint characterized in that it is adapted to be fixed.

[Problems to be Solved by the Invention] In the above-mentioned conventional technique, a taper ring or a seal ring is inserted into a tube by tightening a cap nut to measure a seal and a retainer. Since it does not bite into the tube easily, the tube easily comes off from the joint body, and the sealing property changes with temperature cycle, so the so-called "re-tightening" of the cap nut is required and maintenance is troublesome. There is a problem that it is disadvantageous in cost because it is necessary.

According to the present invention, in order to eliminate the above-mentioned problems, a large diameter portion preliminarily formed in a tube is inserted into an insertion portion protruding from the joint body, and a collar is preliminarily loosely inserted in the tube. The middle portion of the large diameter portion is joined by tightly pressing the ring into the groove ring of the joint body with the large diameter portion sandwiched therebetween against the elasticity of each material of the tube, the insertion portion or the collar ring. A first tube diffractive portion for retaining and liquid-tightness is tightly sandwiched between the outer peripheral surface of the groove ring of the insertion portion of the main body and the inner peripheral surface of the collar ring, and the insertion portion of the insertion portion is formed. By bending and crimping the tube on the end face with the collar of the collar ring,
It is an object of the present invention to provide a tube joint in which the tube bending portion 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 part is formed at the end of the tube made, and a groove ring is provided in this large diameter part, and the insertion part of the joint body made of fluororesin or the like is inserted and loosely inserted into the tube. In addition, a collar ring made of fluororesin or the like is press-fitted into the groove ring of the joint body 4 with the large diameter portion sandwiched therebetween, so that the middle portion of the large diameter portion of the tube is inserted into the groove ring of the insertion portion of the joint body. The tube bending portion is formed by tightly sandwiching the outer circumferential surface and the inner circumferential surface of the flanged ring to form a tube bending portion, and the tube is bent and pressure-bonded to the end surface of the insertion portion by the flange portion of the flanged ring to form a second tube. Reached by forming a bend Is made.

[Operation] After inserting the preliminarily flanged ring into the tube, insert the large diameter part preformed in the tube into the insertion part of the joint body, and the outer peripheral surface of the groove ring formed in this insertion part By tightly press-fitting the collar ring against the elasticity of the material of each member, the outer peripheral surface of the groove ring of the joint body and the inner peripheral surface of the collar ring are tightly fitted in the intermediate portion of the large diameter portion. A sandwiched first tube bend can be formed.

Since the tube bending portion is tightly held by the corner portion of the collar ring and the corner portion of the groove ring, the tube is held liquid-tight with respect to the joint body, and the tube and the collar ring are separated from the joint body. There is no way out.

Further, according to the present invention, the second tube bending portion is formed by holding the middle portion of the tube protruding from the end surface of the insertion portion of the joint body to the above end surface by firmly bending and holding the inner surface of the flange portion of the flanged ring. The tube and the collar ring do not come out of the joint body further, and the cap nut can be omitted.

[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 joint body 4 formed of fluororesin as shown in FIG. 4 in which the groove 3 is formed in the large diameter portion 2 is inserted by the insertion portion 5.

Further, as shown in FIG. 4, the collar ring 6 preliminarily loosely inserted in the tube 1 is moved downward by using the lowering jig b, and the large diameter portion 2 is sandwiched through the state shown in FIG. Then, press fitting is started on the outer peripheral surface of the insertion portion 5 of the joint body 4.

Then, as the press-fitting continues, the large diameter portion 2 of the tube 1 and the outer peripheral surface of the groove ring 3 of the insertion portion 5 and the flanged ring 6
The first tube bending portion 7a as shown in FIG. 6 is formed by being tightly sandwiched between the inner peripheral surface of the tube 1 and the intermediate portion of the tube 1 protruding from the end surface of the insertion portion 5 of the joint body 4. As shown in each of FIGS. 6 to 8, the second tube bending portion 7b is formed by tightly holding the inner surface of the collar portion 6a of the collar ring 6 against the end surface of the insertion portion 5 by bending. Thus, the tube joint according to the present invention is obtained in which the collar ring 6 including the tube 1 does not further come out of the joint body 4 without using the cap nut.

The example shown in FIG. 7 is a cross-sectional view showing another embodiment of the present invention, in which a projecting ring 3a is continuously provided under the groove ring 3 of the joint body 4 as shown in FIG. After inserting the end of the large-diameter portion 2 of the tube 1 into the projecting ring 3a, the large-diameter portion 2 is attached to the outer peripheral surface of the projecting ring 3a on the inner peripheral surface of the lower large-diameter portion 6b of the collar ring 6. By press contacting, the third tube bending portion 7c is further
It is an example of forming.

Further, according to this example, since the three tube bending portions 7a, 7b, 7c are formed in the tube 1, the tube 1 is never removed, and the liquid-tight and air-tightness can be maintained well.

The collar ring 6 is made of plastic such as fluororesin or metal, and the joint body 4 is made of metal or plastic such as fluororesin.

FIG. 8 shows a further embodiment of the present invention, in which two joint bodies of the above embodiment are used and a space between the insertion portions 5,5 of these two joint bodies 4,4 is provided. This is an example in which a tube is connected to a pipe via a collar ring 6.

In each of the above embodiments, the collar ring 6 is mechanically and physically
As shown in the figure, an example has been described in which the tube large-diameter portion 2 is forcibly sandwiched and press-fitted into the insertion portion 5 of the joint body 4, but as another means of this press-fit press fitting, the collar ring 6 is heat-treated. With a tool or the like, the diameter of the large diameter portion 2 of the tube 1 is expanded to an inner diameter larger than the outer diameter of the large diameter portion 2, and the collar ring 6 with the enlarged diameter is provided in the groove ring 3 with the tube 1 sandwiched therebetween. Since the diameter of the flanged ring 6 can be reduced by reheating the flanged ring 6 under the condition that the end of the tube 1 is mechanically press-fitted by the press-fitting jig b, the joint body is Can be tightly jointed to 4.

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, after the preliminarily flanged ring 6 is inserted into the tube 1, the tube 1 is preformed as shown in FIG. 3 through the state shown in FIGS. The large-diameter portion 2 shown in FIG. 4 is inserted into the insertion portion 5 of the joint body 4 as shown in FIG.

Then, the collar ring 6 is passed through the state shown in FIG. 5 and the tube 1,
The material of the insertion portion 5 and the collar ring 6 can be press-fitted against the elastic force of the respective materials to force the snap-in engagement with the snap ring, and the large-diameter portion 2 can be fitted with a sixth As shown in FIG. 6, a first tube bending portion 7a tightly sandwiched between the outer peripheral surface of the groove ring 3 of the insertion portion 5 and the inner peripheral surface of the collar ring 6 is formed as shown in FIG. You can

The first tube bending portion 7a is tightly held by the corner portion of the groove ring 3 and the corner portion of the collar ring 6 as shown in FIG. It is tightly held and does not come out of the insertion portion 5 of the joint body 4.

Further, as shown in each of FIGS. 6 to 8, the intermediate portion of the tube 1 protruding outside from the end surface of the insertion portion 5 of the joint body 4 is formed on the inner surface of the collar portion 6a of the collar ring 6. Since the second tube bending portion 7b is formed by tightly bendingly holding the end face of the fitting portion 5, the collar ring 6 including the tube 1 can be further pulled out from the joint body 4 without using the cap nut. Absent.

Further, if the collar ring 6 is made of a thermoplastic material such as fluororesin, by positively utilizing its heat deformability as described above, the collar shown in FIG. 5 or a collar slightly larger than this diameter is attached. The ring 6 is preheated to have a larger diameter, and the flanged ring 6 is loosely inserted into the tube 1 so that the tube large diameter portion 2
After facing the groove ring 3 by sandwiching it, the collar ring 6 is reheated to reduce the diameter, and as shown in FIG. 6, the tube 1 is tightly sandwiched and pressed onto the outer peripheral surface of the groove ring 3. can do.

Particularly in this case, since it is not necessary to press-fit the flanged ring 6 mechanically as in the above-described embodiment, the press-fitting operation 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 collared ring 6 into the tube 1, the preliminarily formed large diameter portion 2 of the tube 1 is inserted into the joint body 4 at its insertion portion 5, and the collared ring 6 is attached. By forcefully pressing the tube 1, the press-fitting ring 6 and the insertion part 5 with the large-diameter part 2 interposed therebetween against the resilience of the materials, the snap-fitting can be performed with a snap. Alternatively, the ring 6 whose diameter has been increased by preheating is inserted and then reheated to reduce the diameter, so that the outer circumference of the groove ring 3 of the insertion portion 5 of the joint body 4 is reduced to the intermediate portion of the large diameter portion 2. It is possible to form the first tube bending portion 7a which is tightly sandwiched between the surface and the inner peripheral surface of the collar ring 6.

The first tube bending portion 7a is the collar ring 6
Since it is held tightly between the corners of and the corners of the groove ring 3,
The tube 1 is kept liquid-tight with respect to the joint body 4, does not come out of the joint body 4, and the middle portion of the tube 1 which is outside from the end face of the insertion part 5 of the joint body 4 is the end face. By forming the second tube bending portion 7b by bending and holding the inner surface of the collar portion 6a of the collar ring 6 tightly, the collar ring 6 including the tube 1 does not come out of the joint body 4 further. Therefore, the sealability and the pull-out strength are not impaired due to temperature cycle during use or long-term use, and the cap nut itself and its "re-tightening" are not required, which is advantageous in terms of cost and easy to maintain. It has the effect of 1.

And, in particular, in the present invention, even if the cap nut is not used, the tube is snapped to the joint body with the collar ring as described above.
Since it can be surely jointed by locking and locking or by reducing the diameter by reheating the collar ring, the workability at the construction site when connecting pipes is greatly improved compared to the conventional example.
Has the effect of.

[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 joint body, respectively, and FIG. 5 is a cross-sectional view showing the state at the moment when the collar ring is press-fitted into the joint body while sandwiching the tube, and FIG. Is a sectional view of the tube joint press-fitted, FIG. 7 is a sectional view of a collar ring and a tube joint showing another example of the present invention, and FIG. 8 is a sectional view showing another example of use of the tube joint. 1 ... Tube, 2 ... Large diameter part, 3 ... Groove ring, 4 ... Joint body, 5 ... Insertion part, 6 ... Collar ring, 6a ... Collar part,
7a, 7b …… Tube bending part

Claims (1)

[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 a plastic such as fluororesin. , The insertion portion 5 of the joint body 4 having the groove ring 3 in the large diameter portion 2 and made of fluororesin or the like is inserted and loosely inserted into the tube 1,
In addition, the collar ring 6 made of fluororesin, etc.
The intermediate portion of the large-diameter portion 2 of the tube 1 is press-fitted into the groove ring 3 of the joint body 4 by sandwiching it, and the intermediate portion of the large diameter portion 2 of the tube 1 is inserted into the groove ring 3 of the insertion portion 5.
The first tube bending portion 7a is formed by tightly sandwiching it between the outer peripheral surface and the inner peripheral surface of the collar ring 6, and the tube 1 is attached to the end surface of the insertion portion 5 by the collar portion 6a of the collar ring 6.
A tube joint in which the second tube bending portion 7b is formed by refracting and crimping with.