JPH0469488A - Tube joint - Google Patents

Abstract

PURPOSE:To get a tube joint which does not need a cap nut by inserting a fitting part of a joint body having an annular groove inside a large diameter part formed at a tube end, and by press-fitting a flange ring, which is fitted loosely on the tube, into the annular groove of the joint body so as to hold the large diameter part by means of the flange ring. CONSTITUTION:A large diameter part 2 is formed at an end of a tube 1 made of plastics such as fluororesin and the like. A joint body 4 having an annular groove 3 is inserted into the large diameter part 2. A flange ring 6, which is fitted loosely on the tube 1 beforehand, is press-fitted on an outer peripheral surface of a fitting part 5 of the joint body 4 so a to hold the large diameter part 2 by means of the flange ring. Thus, a tube joint is formed, because a first tubular bent part 7a is formed, and further a second tubular bent part 7b is formed by bending and holding tightly an inter-mediate part of the tube 1 extending from the fitting part 5 of the joint body 4 by means of an inner surface of a flange part 6a of the flange ring 6 against an end face of the fitting part 5. As a result, it is possible to join tubes surely without using a cap nut.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a tube joint, and more specifically to a tube joint that does not use a cap nut and is suitable as a joint for synthetic resin tubes, particularly fluororesin tubes.

[Prior art] This type of tube joint has been conventionally used, for example, in the
Some of them are described in Japanese Patent No. 52391.

This conventional technology includes a joint body, a cap nut for attaching a synthetic resin hard pipe to the joint body, and a trapezoidal seal ring that fits into a tapered hole communicating with a pipe insertion hole in the joint body. and a trapezoidal taper ring provided with a wide slanted groove that fits into the taper hole that communicates with the female threaded part of the cap nut.A compressive force is applied to the pipe in the direction of its center, and the outer periphery of the pipe is This pipe joint is characterized by being fixed by being deformed.

1. Problem to be Solved by the Invention J The above-mentioned conventional technology measures a seal and prevents the tube from coming off by inserting a taper ring or a seal ring into the tube by tightening a cap nut, but there is no insert inside the tube. Therefore, the tube does not bite into the tube easily, and the tube easily comes off from the joint body.Also, the sealing property changes with temperature cycles, so the so-called "retightening" of the cap nut is required, making maintenance troublesome. Therefore, there was a problem that it was disadvantageous in terms of cost.

In order to eliminate each of the above-mentioned problems, the present invention includes a large diameter portion formed in advance on a tube, which is inserted into an insertion portion protruding from a joint body, and a flanged ring that is loosely inserted into the tube in advance. By tightly press-fitting the large diameter part into the groove ring of the joint body against the elasticity of each material of the tube, insertion part, or flanged ring, the middle part of the large diameter part is inserted into the joint body. A first bent tube portion is formed between the outer peripheral surface of the groove ring of the insertion portion and the inner peripheral surface of the flanged ring to prevent the tube from coming off and to maintain liquid tightness, and the end surface of the insertion portion is By bending and crimping the tube with the flange of the flange ring, the second
It is an object of the present invention to provide a tube joint in which a tube bent portion is formed.

[Means for Solving the Problems] An object of the present invention described above is to attach a tube by forming a deformed part on the tube to form a tube joint that prevents the tube from coming off. A large diameter part is formed at the end of the tube made of aluminum, and the insertion part of the fitting body, which has a groove ring and is made of fluororesin or the like, is inserted into the large diameter part, and is loosely inserted into the tube. , and by press-fitting a flanged ring made of fluororesin or the like into the groove ring of the joint body with the large diameter part sandwiched therebetween, the middle part of the large diameter part of the tube is inserted into the groove ring of the insertion part of the joint body. The tube is tightly sandwiched between the outer circumferential surface and the inner circumferential surface of the flanged ring to form a tube bending section, and the tube is bent and crimped to the end surface of the insertion section using the brim of the flanged ring to form a second tube. This is achieved by forming a refractive section.

"Function" After inserting the flanged ring into the tube in advance, insert the large diameter part previously formed in the tube into the insertion part of the joint body, and the outer periphery of the groove ring formed in this insertion part. By tightly press-fitting the flanged ring into the surface against the elasticity of the material of each member, the outer circumferential surface of the groove ring of the joint body and the inner circumferential surface of the flanged ring fit into the middle part of the large diameter portion. The first one is tightly sandwiched.
A tube bent portion can be formed.

Since this tube bent portion is tightly held between the corner of the flanged ring and the groove ring, the tube is kept liquid-tight with respect to the joint body, and the tube and flanged ring are separated from the joint body. There's no way out.

Furthermore, in the present invention, a second tube bending part is formed on the end face of the joint body to tightly bend and hold the middle part of the tube protruding from the end face of the insertion part of the joint body. In addition, the flanged ring, including the tube, is prevented from slipping out from the joint body, and the cap nut can be omitted.

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

First of all, the basic structure of this invention is that the tube is attached by forming a deformed part on the tube to form a tube joint that prevents it from coming off, and is made of plastic such as fluororesin as shown in Figure 1. 2 and 3 using a heat forming jig a as shown in the same figure at the end of the tube 1.
A large diameter portion 2 as shown in the figure is formed.

Then, a joint body 4 molded from fluororesin as shown in FIG.
Insert with .

Further, as shown in FIG. 4, the flanged ring 6, which has been loosely inserted into the tube 1 in advance, is moved downward using a lowering jig, and after passing through the state shown in FIG. At this point, it begins to be compressed onto the outer circumferential surface of the insertion portion 5 of the joint body 4.

Then, by continuing the above press-fitting, the large diameter portion 2 of the tube
is tightly sandwiched between the outer circumferential surface of the groove ring 3 of the insertion portion 5 and the inner circumferential surface of the flanged ring 6 to form a first section as shown in FIG.
The tube bent portion 7a is formed, and the intermediate portion of the tube 1 protruding from the end face of the insertion portion 5 of the joint body 4 is attached to a flange ring as shown in FIGS. 6 to 8. By forming the second tube bent part 7b by tightly bending and holding the inner surface of the flange part 6a of the flange part 6a on the end face of the insertion part 5, the flange ring 6 including the tube 1 can be attached without using a cap nut. A tube joint according to the present invention is obtained which further prevents the tube from slipping out from the joint body 4.

Further, the example shown in FIG. 7 is a sectional view showing another embodiment of the present invention, which has a protruding ring 3a continuously provided below the groove ring 3 of the joint body 4 as shown in the same figure. , this protrusion 3a
After inserting the end of the large diameter portion 2 of the tube I into the tube I, the inner circumferential surface of the lower large diameter portion 6b of the flanged ring 6 presses the diameter portion 2 against the outer circumferential surface of the protruding ring 3a. This is an example in which a third tube bent portion 7c is formed.

According to this example, there are three tube bending parts 7a and 7b.
, 7c are formed on the tube 1, so there is no need to remove the tube 1, and moreover, the liquid-tightness can be maintained satisfactorily.

The flange 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 still another embodiment of the present invention, in which two joint bodies of the previous embodiment are used, and between the insertion portions 5.5 of these two joint bodies 4.4. the tube 1
This is an example in which piping is connected via a flanged ring 6.

In each of the above embodiments, the flanged ring 6 is mechanically and physically
As shown in the figure, an example has been described in which the tube is forcibly inserted into the insertion portion 5 of the joint body 4 with the large diameter portion 2 between them. The inner diameter of the large-diameter portion 2 of the tube 1 is expanded in advance using a tool or the like, and the large-diameter flanged ring 6 is inserted into the groove ring 3 with the tube 1 in between. Since the diameter of the flanged ring 6, which has already been enlarged, can be reduced in diameter by reheating the flanged ring 6, the end of the tube 1 can be mechanically press-fitted into the fitting body using the press-fitting jig. Can be joined tightly to 4.

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

First, the flanged ring 6 is inserted into the tube 1 in advance, and then the tube I is preformed as shown in FIG. 3 through the state shown in FIGS. A large diameter portion 2 is inserted into the insertion portion 5 of the joint body 4 as shown in FIG.

Then, the flanged ring 6 is placed in the state shown in FIG.
By forcibly press-fitting the insertion portion 5 and the flanged ring 6 against the elasticity of each material, it can be fitted with a single click, and the sixth As shown in the figure, the first tube bent portion 7a is tightly sandwiched between the outer circumferential surface of the groove ring 3 of the insertion portion 5 and the inner circumferential surface of the flanged ring 6.
can be formed as shown in FIG.

This first tube bent portion 7a is tightly held between the corner of the groove ring 3 and the corner of the flanged ring 6 as shown in FIG. It is tightly held and does not slip out from the insertion part 5 of the joint body 4.

Furthermore, the middle part of the tube 1 protruding from the end face of the insertion part 5 of the joint body 4 is inserted into the inner surface of the flange part 6a of the flange ring 6, as shown in FIGS. 6 to 8. By forming the second tube bending part 7b by tightly bending and holding the fitting part 5 on the end face of the fitting part 5, the flanged ring 6 including the tube 1 will be prevented from slipping out from the joint body 4 even without using a cap nut. .

Furthermore, if the flanged ring 6 is made of a thermoplastic material such as fluororesin, by actively utilizing its thermal deformability as described above, the flanged ring 6 can be flanged to the diameter shown in FIG. 5 or a slightly larger diameter. The diameter of the ring 6 is increased in advance by heating, and the flanged ring 6 is loosely inserted into the tube l, and the large diameter portion 2 of the tube is inserted.
If the flanged ring 6 is reheated to reduce the diameter of the flanged ring 6, the tube 1 can be tightly sandwiched and press-fitted onto the outer peripheral surface of the groove ring 3, as shown in FIG. can do.

Particularly in this case, it is not necessary to press-fit the flanged ring 6 mechanically or physically as in the previous embodiment, so that the press-fitting operation can be carried out even more easily.

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

After inserting the flanged ring 6 into the tube 1 in advance, insert the large diameter portion 2 previously formed in the tube 1 into the joint body 4 at its insertion portion 5, and then insert the flanged ring 6 into the tube 1. By forcefully press-fitting the tube 1, the press-fit ring 6, and the insertion part 5 with the large-diameter part 2 in between, against the elasticity of each material, the fitting can be achieved with a single snap. , or by heating the ring 6 which has been made larger in diameter in advance by heating and reducing its diameter after insertion, the outer periphery of the groove ring 3 of the insertion part 5 of the joint body 4 is formed in the middle part of the large diameter part 2. A first tube bent portion 7a can be formed which is tightly sandwiched between the surface and the inner peripheral surface of the flanged ring 6.

Since the first tube bent portion 7a is tightly held between the corner of the flanged ring 6 and the groove ring 3, the tube 1 is held liquid-tight with respect to the joint body 4, and It does not fall out from the main body 4, and the joint main body 4
The middle part of the tube 1 protruding from the end face of the insertion part 5 is tightly bent and held at the end face by the inner surface of the flange part 6a of the flange ring 6 to form a second tube bent part 7b. , starting from the tube 1, the flanged ring 6 is connected to the joint body 4.
Therefore, the sealing performance and removal strength are not impaired by temperature cycles during use or long-term use, and there is no need to retighten the cap nut itself, which is advantageous in terms of cost. The first effect is that maintenance is easy.

In particular, in this invention, even if a cap nut is not used, the tube can be snapped onto the joint body using the flanged ring as described above.
The second method greatly improves workability at the construction site when connecting pipes, compared to the conventional example, because the joint can be reliably joined by locking the piping or by reducing the diameter by reheating the flanged ring.
It has the effect of

[Brief explanation of the drawing]

Each of the figures shows an embodiment of the present invention. Figure 1 is a cross-sectional view of a tube and a heat-forming jig, and Figure 2 is a tube that is press-fitted into a heat-forming jig to form a large diameter part. cross section,
Figures 3 and 4 are cross-sectional views showing the procedure for inserting the tube into the joint body, Figure 5 is a cross-sectional view showing the moment when the flanged ring is press-fitted into the joint body with the tube in between, and Figure 6r! gJ is a cross-sectional view of the tube joint press-fitted, No. 7
The figure is a cross-sectional view of a flanged ring and a tube joint showing another example of the present invention, and FIG. 8 is a cross-sectional view showing another example of how the tube joint is used. 1...Tube 5...Insertion part 2...Large diameter part 6...Flanged ring 3...Groove ring
6a... Flange 4... Joint body 7a, 7b... Tube bending part 7 a, 7 b...-Tube bending part Fig. 3 7 a, 7 b... Tube bending part Fig. 4

Claims (1)

[Claims] In a tube fitting that prevents the tube from coming off by forming a deformed part on the tube when it is attached, a large diameter part 2 is formed at the end of the tube 1 made of plastic such as fluororesin, and this large diameter part Groove ring 3 inside 2
The insertion portion 5 of the joint body 4 made of fluororesin or the like is inserted, and the flange ring 6, which is loosely inserted into the tube 1 and made of fluororesin or the like, is inserted between the large diameter portion 2. By press-fitting into the groove ring 3 of the joint body 4, the middle part of the large diameter portion 2 of the tube 1 is connected to the outer peripheral surface of the groove ring 3 of the insertion part 5 and the inner peripheral surface of the flanged ring 6. A first tube bent portion 7a is formed by tightly sandwiching the tube 1, and a second tube bent portion 7b is formed by crimp-bonding the tube 1 to the end face of the insertion portion 5 with the flange 6a of the flange ring 6. A tube fitting made by