JPH088380Y2 - Pipe joint structure - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to fluid equipment such as various valves, filters, pumps, flowmeters, tanks, etc., for example, fluid pipes such as pipes for supplying high-purity chemical liquids or ultrapure water for semiconductor manufacturing. The present invention relates to a pipe joint structure for connecting to each other.

[0002]

2. Description of the Related Art As a pipe joint structure of this type, the present applicant has filed Japanese Utility Model Application No. 1-69378 (Japanese Utility Model Application No. 2-117494).
A resin pipe joint having a structure as shown in Japanese Laid-Open Patent Publication No. 2004-242242 has been previously proposed.

FIG. 9 shows a pipe joint structure for connecting to the previously proposed conventional fluid equipment. In FIG. 9, a receiving port 93 into which the one-end pushing portion 92A of the fluid pipe 92 is inserted is formed at the tip end side of the joint main body 91 whose base end side is connected to the fluid device main body (not shown).
94 is a separate body from the joint main body 91, or FIG.
Is a sleeve portion as an inner ring that is integrally formed as described above and is press-fitted into the one end pushing portion 92A of the fluid pipe 92, and the one end pushing portion 92A is provided at the tip end portion thereof.
A bulging portion 94A having a chevron cross section is formed so as to expand the diameter of the one-end pushing portion 92A when it is pressed into the. 95 is a pressing ring having a female thread portion 97 screwed to the male screw portion 96 formed on the outer circumferential surface of the socket 93. Reference numerals 98 and 99 denote primary and secondary seal portions formed at the inner and inner portions of the receiving port 93 inclining with respect to the axis, and 100 and 101 respectively correspond to the primary and secondary seal portions 98 and 99. Sealing portions are formed at the inner end and the outer end of the inner ring 94, respectively. In the case where the sleeve portion 94 shown in FIG. 10 is integrally formed with the joint body portion 91, the seal portion 98 is not necessary.

In the structure described above, when the sleeve portion 94 is press-fitted into one end pushing portion 92A of the fluid pipe 92 which is inserted into the fluid pipe insertion hole 102 of the push ring 95, the bulging portion 94A having a chevron cross section causes the fluid pipe 92 to move. One end pushing part 92A
A chevron-shaped annular expanded portion 103 is formed at the bottom. The inner thread edge 97A of the push ring 95 is formed by screwing the female thread portion 97 of the push ring 95 into the male thread portion 96 on the joint body 91 side and screwing it forward.
The outer peripheral surface of the fluid pipe 92 is pressed by, and the primary and secondary seal portions 98 and 99 are formed in the inner and inner portions of the receiving port 93 inclining with respect to the axis, and the sleeve portion 94 corresponding thereto. A sealing force is applied to the seal portions 100 and 101 formed at the inner end portion and the outer end portion, respectively, and the joint main body portion 91 and the fluid pipe 92 are liquid-tightly connected.

[0005]

In the conventional pipe joint structure having the above-described structure, the sleeve portion 94 is press-fitted into the fluid pipe 92, so that the inner diameter of the sleeve portion 94 is smaller than the inner diameter of the fluid pipe 92. There is a need. Therefore, a step H is generated between the tip of the sleeve portion 94 and the inner circumference of the root 104 of the enlarged diameter portion 103 of the fluid pipe 92, and a liquid pool tends to be generated there.

[0006] If this liquid pool is large, when it is used in a piping line of a semiconductor manufacturing facility, etc., the replaceability of a chemical liquid or pure water liquid becomes poor, or it becomes a factor of generating particles, and as a fluid, for example, a resist is used. In the case where the viscosity affects the film thickness of the wafer such as a liquid, the resist liquid stays in the liquid pool H, and the liquid is deteriorated to make it impossible to correctly control the film thickness of the wafer. This will cause defects. Also, when the liquid is exchanged, the residual liquid whose replacement property has deteriorated due to the liquid pool is mixed into the new liquid, and the purity cannot be guaranteed with ultrapure water, for example. Furthermore, if there is such a fitting with a large amount of liquid pool after the last filter in the piping line, the particles staying here will come out for a long time, which may reduce the yield of wafers. There is.

From this point of view, as shown in FIG. 11, the tip side slope 94B of the bulging portion 94A of the sleeve portion 94 is formed.
Although it was considered that the liquid pool portion H was made smaller in volume by increasing the inclination of, the liquid pool portion H could not be made so small in actuality, and the liquid replacement characteristics were greatly improved. It wasn't possible.

The present invention has been made in view of the above circumstances, and not only can secure excellent sealing performance regardless of temperature fluctuation of fluid, but also can be three- dimensionally improved by a simple improvement .
And the inner circumference of the base of the expanded portion of the fluid pipe
An object of the present invention is to provide a pipe joint structure capable of surely preventing a trouble such as a decrease in purity due to fluid retention caused by a step between the pipes, and exhibiting a strong retaining function for the fluid pipe. I am trying.

[0009]

In order to achieve the above object, the pipe joint structure according to claim 1 of the present invention has a receiving opening into which one end pushing portion of a fluid pipe is inserted, and an outer peripheral surface thereof. A tubular joint main body having a male threaded portion on its surface, and a resin sleeve portion formed in the socket of the joint main body,
A pipe joint structure, which is capable of being screwed into an outer peripheral male thread portion of the joint body, and which includes a push ring that gives a sealing force by screwing,
In a pipe joint structure in which an annular chamfer that is inclined to the inner peripheral surface of the fluid pipe is formed at the inner peripheral edge on the tip side of the sleeve portion, the inclination angle of the chamfer is 10 ° to 48 °.
Within the range, a bulge portion that bulges in the radial direction is formed on the sleeve portion, and an inner end edge portion that directly presses the fluid pipe from the outer peripheral surface of the fluid pipe is formed on the push ring. The end portion and the end edge of the sleeve portion on the front end side are configured to hold the fluid pipe in a retaining state.

Further, the pipe joint structure according to claim 2 of the present invention, as well as has a socket having one end pushing portion of the fluid tube is inserted into the inner circumferential surface, it has a male thread portion on an outer peripheral surface, the fluid device body It is possible to screw the cylindrical joint body integrally formed with the sleeve, the resin sleeve portion formed in the receiving port of the joint body, and the outer peripheral male screw portion of the joint body, and to secure the sealing force by screwing. providing a pipe joint structure comprising a junk ring, the inner peripheral edge of the distal end side of the sleeve portion, the pipe joint structure formed a chamfered portion of the inclined annular to the inner peripheral surface of the fluid tube, the chamfered The inclination angle of the part is within the range of 10 ° to 48 °
And a bulging portion that bulges in the radial direction is formed on the sleeve portion, and an inner end edge portion that directly presses the fluid pipe from the outer peripheral surface of the fluid pipe is formed on the push ring. And the end edge of the sleeve portion on the front end side is configured to hold the fluid pipe in a retaining state.

[0011]

In the first and second aspects of the present invention having the above construction ,
According to the pipe joint structure described above , in a state in which the one-end pushing-in portion of the fluid pipe is inserted into the receiving opening of the joint main body portion, the push ring is screwed to the outer peripheral male thread portion of the joint main body portion to advance the joint. A strong sealing force can be generated between the receiving port of the main body and the fluid pipe to suppress stress relaxation due to temperature fluctuations and maintain good sealing between the joint main body and the fluid pipe. it can. Further, the inner peripheral edge on the tip side of the sleeve portion formed in the receiving opening of the joint main body portion has a range of 10 ° to 48 °.
By forming a chamfer set at an angle of inclination
The inner diameter of the sleeve is smaller than the inner diameter of the fluid pipe.
Even if it is, there is no big step
Of course, as the push ring is threaded, the inner edge of the push ring slips.
When located on the outer peripheral side of the tip of the sleeve,
The fluid pipe is sandwiched between the tip edge and the inner edge of the push ring.
The inner edge of the push ring
Ride on the tip of the sleeve and let the tip of the sleeve flow.
It falls to the inner diameter side of the body canal, causing a new step
It will not live. Therefore, a liquid pool due to the generation of the step is not formed, and the fluid can be made to flow smoothly to avoid the inconvenience such as the decrease in purity. Also, the above
As described above, the fluid pipe is formed by the end edge on the tip side of the sleeve portion that is sharpened with the formation of the chamfered portion and the inner end edge portion formed on the push ring that directly presses the fluid pipe from the outer peripheral surface of the fluid pipe. The fluid pipe can be strongly prevented from coming off by holding it in a sandwiched manner and expanding the peripheral wall of the fluid pipe by the bulging portion formed in the sleeve portion.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Figure 1 is a longitudinal section of the manual stop valves as an example of a fluid device applying the present invention, reference numeral 1 denotes a valve body, the valve body 1 is, for example PTEF, PFA, ETFE, CTFE, It is made of a resin having excellent chemical resistance and heat resistance such as ECTFE. On both sides of the resin, tubular joint main bodies 2 and 2 are integrally formed concentrically with the axis C of the internal fluid passage 1A. A shaft-shaped valve body 5 is fitted and supported on the central rising portion 1B in the axial direction through an outer ring 3 and a pusher ring 4 so that the shaft-shaped valve body 5 can be moved up and down and opened and closed. A manual stop valve is configured by fixing the opening / closing operation knob 6 to the portion via a lift shaft 7.

The tubular joint main body 2 has a receiving port 9 formed on the inner peripheral surface thereof into which a one-end pushing-in portion 8A of a fluid pipe 8 described later is inserted, and a male screw portion 10 on the outer peripheral surface thereof. Are formed. As shown in FIG. 2, the inner diameter of the receiving port 9 is larger than the inner diameter of the fluid channel 1A, and the inner diameter of the fluid channel 1A is gradually reduced from its inner end toward the axially outward direction. By forming a taper surface reaching the above, the primary seal part 11 is formed in the inner part of the receiving port 9, and
By gradually increasing the diameter from the radially inner surface in the vicinity of the outer end of the receiving port 9 toward the outer side in the axial direction to form a tapered surface reaching the tip of the male screw part 10, the inlet part of the receiving port 9 is formed. The secondary seal portion 12 is formed.

Reference numeral 13 denotes an inner ring as a sleeve portion. The inner ring 13 is fitted to the inner end portion of the inner ring 13 as shown in FIG. 2 and FIG. A portion 13A, a press-fitting portion 13B having a diameter smaller than that of the fitting portion 13A by an amount corresponding to the wall thickness of the fluid pipe 8, and an outer end portion in the axial direction of the fitting portion 13A from the outer end toward the inner side in the axial direction. A bulging portion 13C having a mountain-shaped cross-section that gradually increases in diameter and then gradually reduces in diameter is continuously formed to have a sleeve shape as a whole, and an inner end of the fitting portion 13A is formed in the joint body portion 2. An inner end seal portion 14 that abuts the primary seal portion 11 in the inner portion of the receiving opening 9 is formed, and further, the diameter is gradually reduced from the top of the bulging portion 13C toward the inner end side of the inner ring 13 and the receiving opening is formed. 9 through the secondary seal portion 12 at the inlet of the fluid pipe 8. Outer end sealing portion 15 is formed in contact with Te.

In the inner ring 13 (sleeve portion) as described above, as clearly shown in FIG. 2, the press-fitting portion 13B and the bulging portion 13C are press-fitted into one end of the fluid pipe 8 to form the fluid pipe 8.
By enlarging the diameter of the peripheral wall of the joint, it is integrally coupled to the fluid pipe 8 in a retaining state, whereby the one-end push-in portion 8A that can be inserted into the receiving port 9 of the joint main body portion 2 has a chevron-shaped annular portion 8A.
C is formed. Further, at this time, the tapered surface portion 13D having a diameter gradually reduced from the top portion of the inner ring 13 toward the outer end side is brought into contact with the inner surface of the inclined portion 8B of the fluid pipe 8 to form the fluid pipe 8 and the inner ring 13. A seal portion therebetween is formed.

Reference numeral 16 denotes a push ring, which is a tubular portion 16A having a female screw portion 17 that can be screwed into the male screw portion 10 of the joint body 2 and an annular pressing portion 16B having a fluid pipe insertion hole 18.
And an inner end edge portion 16C having a diameter substantially equal to the outer diameter of the fluid pipe 8 is formed at the inner end portion of the inner peripheral surface of the annular pressing portion 16B. The inner ring 13 is pressed against the joint body 2 side by screwing the male threaded portion 10 of the joint body 2 through the threaded portion 10 and screwing the inner ring 13 inward in the direction of the axis C. The inner end edge portion 16C of the push ring 16 is pushed into a part of the outer peripheral surface of the fluid pipe 8 to integrally join the joint main body portion 2, the inner ring 13 and the fluid pipe 8, and the primary seal portion 11 And the inner end seal portion 14 are provided with a sealing force, and the secondary seal portion 12, one end of the fluid pipe 8 and the outer end seal portion 15 are also provided with a sealing force.

At the inner peripheral edge of the inner ring 13 on the front end side, as shown in FIGS. 2 and 3, an annular chamfer inclined toward the inner periphery of the root portion 8D of the enlarged diameter portion 8c of the fluid pipe 8. The part 19 is formed . Inclination of this chamfer 19
If the inclination angle θ is less than 10 ° or exceeds 48 °, the pull-out strength is strong.
Since the degree is significantly reduced, the
The angle is preferably set in the range of 20 ° to 45 °, and the inner peripheral edge 13E on the front end side of the inner ring 13 and the inner end edge of the push ring 16 which are sharpened due to the formation of the chamfered portion 19. The fluid pipe 8 is sandwiched and held by 16C so as to be prevented from coming off.

Next, the operation of the above configuration, that is, the procedure for connecting the fluid pipe to the manual stop valve will be described. First, one end of the fluid pipe 8 is passed through the fluid pipe insertion hole 18 of the push ring 16, and then the press-fitting portion 13B and the bulging portion 13C of the inner ring 13 are press-fitted into the one end of the fluid pipe 8 which has passed through the fluid pipe. By enlarging the diameter of the peripheral wall of the inner ring 13, the inner ring 13 is integrally coupled to the fluid pipe 8 in a retaining state to form the one-end pushing portion 8A that can be inserted into the receiving port 9 of the joint body 2. At this time, the tapered surface portion 13D having a diameter that gradually decreases from the top portion of the inner ring 13 toward the outer end side comes into contact with the inner surface of the inclined portion 8B of the fluid pipe 8 to seal the space between the fluid pipe 8 and the inner ring 13. To be done.

Then, the one end pushing portion 8 of the fluid pipe 8 is pushed.
A is inserted into the receiving port 9 of the tubular joint body 2 integrally formed with the valve body 1 to bring the inner end seal portion 14 into contact with the primary seal portion 11 and the outer end seal portion 15 to the fluid pipe. The secondary seal portion 12 is brought into contact with the one end portion 8 through the one end portion. In this state, the female screw portion 17 of the push ring 16 is connected to the joint body 2
The inner ring 13 is screwed into the male thread portion 10 of the inner ring 13 and screwed inward in the direction of the axis C to be tightened.
Was pressed against the joint body 2 side, and the inner end edge 16C of the push ring 16 was positioned on the outer periphery of the tip end portion of the inner ring 13.
When, by holding sandwiching the fluid tube 8 More and inner end edge 16C of the distal end side of the inner peripheral edge 13E and <br/> pressing ring 16 of the inner ring 13, an inner end edge 16C and the inner peripheral edge 1
3E is made to bite into a part of the outer peripheral surface and the inner peripheral surface of the fluid pipe 8, respectively. As a result, the inner ring 13
Even if the tip does not fall to the inner diameter side of the fluid pipe 8,
In addition, the fluid pipe 8 can be held in a very strong retaining state.

Further, due to the screwing of the push ring 16, the fluid pipe 8 is
Is pressed against the joint body portion 2 side, the primary seal portion 11 and the inner end seal portion 14, the secondary seal portion 12, the one end portion of the fluid pipe 8 and the outer end seal portion 15 are brought into pressure contact with each other, and between them. A strong sealing force is generated, and reliable sealing is performed on both the outer circumference and the inner circumference of the fluid pipe 8, and the deterioration of the sealing property due to stress relaxation is suppressed as much as possible regardless of the temperature fluctuation of the fluid, which is excellent for a long time. The sealing property can be secured.

In particular, by forming the annular chamfered portion 19 at the inner peripheral edge of the inner ring 13 on the tip side,
A step is not generated between the inner circumference of the root portion 8D of the expanded diameter portion 8C and the tip of the inner ring 13 in the fluid pipe 8.
Of course, the inner edge 16C of the push ring 16 is the inner ring.
Depending on the positional relationship such rides on the tip portion of the grayed 13
The tip of the inner ring 13 falls to the inner diameter side of the fluid pipe 8.
It does not generate a new step due to the inclusion. That is, the liquid pool is not formed at all , and the flow path characteristics such that the fluid can be smoothly flowed without staying are ensured, and the occurrence of troubles such as a decrease in purity when the high-purity liquid is flowed is prevented. At the same time, the inner peripheral edge on the front end side of the inner ring 13 is made sharp, and the sharp inner peripheral edge 13E and the inner end edge 16C of the push ring 16 hold the fluid pipe 8 to hold it. The retaining function for 8 can be made very strong.

In the above embodiment, since the tubular joint body portions 2 are integrally formed with the fluid equipment such as the valve body 1, the fluid pipe 8 is directly connected to the fluid equipment. However, of course, this pipe joint structure is applied to a socket-type, elbow-type, T-type, etc. pipe joint in which the tubular joint main body 2 is integrally formed, and the fluid pipe is connected via this pipe joint. It goes without saying that it is also applicable to the case where 8 is connected to a fluid device.

Next, a sample of an elbow type pipe joint adopting the pipe joint structure was prepared in order to evaluate the displacement characteristic of the liquid for the pipe joint structure having the above structure, and a liquid pool preliminary test was conducted. This will be described with reference to FIG.

In FIG. 4, a pair of elbow type pipe joint samples M are connected by a liquid pipe 8, and fittings 40, 40 are connected to each sample M, respectively. In this state, 80 ml of 98% sulfuric acid is sealed through each fitting 40,
After leaving for 5 minutes, pull out everything. Then, pure water 8
After adding 0 ml and leaving it for 1 minute, it is transferred to a container. This was the first washing, and further washing with pure water was repeated 10 times in total, and the sulfuric acid concentration of the washing water was measured each time. The test temperature was 25 ° C., and ion chromatography was used to measure the concentration. In addition to the above-mentioned example, similar measurements were carried out using a conventional pipe joint shown in FIG. 9 and a pipe joint shown in FIG. 11 as comparative examples.

FIG. 6 showing the measurement results of the above liquid pool preliminary test.
As is clear from the graph, the sulfuric acid concentration of the conventional product represented by the characteristic b and the comparative product C represented by the characteristic c do not decrease so much even if the number of times of washing is increased, while the product of the embodiment represented by the characteristic a. It was found that the concentration of sulfuric acid was significantly decreased with the increase in the number of washings, and the liquid pool was small.

From the results of the preliminary test of the liquid pool, it was confirmed that the products of Examples had good characteristics, so that the pure water displacement characteristics were tested. This will be described with reference to FIG.

As shown in FIG. 5, the five example products M are
Connect with FA pipe 8, inject 98% sulfuric acid from one end, leave it for 5 minutes, then discharge it and connect it to an ultrapure water device (not shown) to flow 1.7 l / min of ultrapure water. The specific resistance value was continuously measured at the edge to evaluate its recovery rate. The same measurement was performed for the conventional product. The test results are shown in FIG.

As shown by the characteristic β in FIG. 7, it takes time for the conventional product to reach a constant specific resistance value, whereas the embodiment product has a short time as shown by the characteristic α. It was confirmed that the specific resistance value became constant over time, and that good pure water displacement characteristics were exhibited.

By the way, the liquid pool is the inner ring 13
In order to verify whether or not it occurs on the tip side of the joint, in addition to the conventional product, a joint body 2 with an inner ring 13 integrated as shown in FIG. 10 is prepared. As a result of a test, the integrated product as shown in FIG. 10 shows no great difference from the conventional product as shown by the characteristic γ in FIG. 12, and a liquid pool exists at the tip side of the inner ring 13. I was able to confirm that. In other words, it was found that the effect of providing the chamfered portion 19 is surely exhibited in the example product.

Subsequent to the pure water displacement characteristic test, tests relating to basic performance such as pull-out strength were conducted, and favorable results were obtained in each case.

In the above embodiment, the inner ring 1
3 is shown as a separate body from the joint body 2,
Even if the portion 13 corresponding to the inner ring is integrated with the joint body 2 as shown in FIG. 8, the chamfered portion 19 similar to that in the above-described embodiment should be formed on the inner ring corresponding portion 13. As a result, the same effect can be obtained.

In the above embodiment, the valve main body 1 and the joint main body 2 are integrally formed of resin having excellent characteristics of chemical resistance and heat resistance, but the valve main body 1 is made of metal. The joint body portion 2 may be integrally formed by cutting.

[0033]

As described above, according to the first and second aspects of the present invention, the joint body portion of the joint body is inserted with the one-end pushing portion of the fluid pipe inserted into the receiving opening of the joint body portion. By screwing the push ring onto the outer peripheral thread of the
A strong sealing force is generated between the joint body and one end of the fluid pipe to suppress the stress relaxation due to temperature fluctuations. Good sealing property can be ensured. Moreover, the inclination angle is set within the range of 10 ° to 48 ° at the inner peripheral edge on the tip side of the sleeve portion formed in the receiving port of the joint body.
Since the chamfered part is formed , the inner diameter of the sleeve part
Even if the diameter is smaller than the inner diameter of the fluid pipe,
Not only does it cause no uneven steps, but the push ring
As it advances, its inner edge is on the outer circumference of the tip of the sleeve.
When it is positioned at the
The inner end edge of the push ring rides on the tip of the sleeve so that the fluid pipe is sandwiched and held by the inner end edge.
The tip of the sleeve to the inner diameter side of the fluid pipe.
In addition, a new step is not generated due to that. So
Therefore, it is possible to reliably prevent the retention of fluid due to the generation of steps.
In this way, the fluid can be made to flow smoothly and inconveniences such as a decrease in purity can be eliminated, and in particular, it can be effectively used as a joint for connecting a pipe for high-purity liquid or ultrapure water and a fluid device. . In addition , the fluid pipe is formed by the end edge on the tip side of the sleeve portion that is sharpened with the formation of the chamfered portion and the inner end edge portion that is formed on the push ring and directly presses the fluid pipe from the outer peripheral surface of the fluid pipe. The fluid pipe can be extremely strongly prevented from coming off due to the synergistic effect of sandwiching and holding and expanding the diameter of the fluid pipe peripheral wall by the bulging portion formed in the sleeve portion.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a manual stop valve as an example of a fluid device to which the present invention is applied.

FIG. 2 is a vertical sectional view of a main part of FIG.

FIG. 3 is a partially cutaway enlarged side view showing an inner ring (sleeve portion) used in the one shown in FIG.

4 is a diagram showing piping for a liquid pool preliminary test of the pipe joint structure of FIG.

FIG. 5 is a diagram showing piping for a pure water displacement characteristic test of the pipe joint structure.

FIG. 6 is a characteristic diagram showing the results of a liquid pool preliminary test of the pipe joint structure in comparison with those of a conventional product and a comparative example product.

FIG. 7 is a characteristic diagram showing the pure water displacement characteristic test results of the pipe joint structure in comparison with those of a conventional product.

FIG. 8 is a vertical sectional view of a pipe joint structure showing another embodiment of the present invention.

FIG. 9 is a vertical cross-sectional view showing a conventional pipe joint structure previously proposed by the applicant.

FIG. 10 is a vertical sectional view showing a conventional pipe joint structure in which a seal ring is integrated with a joint body.

FIG. 11 is a vertical cross-sectional view showing an improvement plan of a conventional pipe joint structure.

FIG. 12 is a characteristic diagram showing the pure water displacement characteristic test results of the seal ring integrated with the joint body together with that of the conventional product.

[Explanation of symbols]

 1 Valve Main Body (Fluid Device Main Body) 2 Joint Main Body 8 Fluid Pipe 8A One End Pushing Part 8C Expanding Part 9 Receptacle 10 Male Thread Part 11, 12, 14, 15 Seal Part 13 Inner Ring (Sleeve Part) 13C Bulging Part 13E Sharp tip edge 16 Push ring 16C Inner edge 17 Female thread 19 Chamfer

Continuation of the front page (72) Nobuhito Hirakawa Inventor Shinji Hirakawa 1 at 541, Shimouchi Shinji, Hitago-shi, Mita Plant, Japan Pillar Industry Co., Ltd. (56) Reference JP 58-28086 (JP, A) Actual Kaihei 2-117494 (JP, U)

Claims (2)

[Scope of utility model registration request] 1. A cylindrical joint main body having an inner peripheral surface with a receiving end into which one end of a fluid pipe is inserted, and an outer peripheral surface having a male threaded portion, and the joint main body formed with the receiving opening. And a resin sleeve portion and a push ring that can be screwed into the outer peripheral male thread portion of the joint body portion and that gives a sealing force by screwing, the inner peripheral end of the sleeve portion on the tip side. In a pipe joint structure in which an annular chamfer that is inclined to the inner peripheral surface of the fluid pipe is formed on the edge, the inclination of the chamfer is
The angle of inclination is set within the range of 10 ° to 48 °, a bulging portion that bulges in the radial direction is formed on the sleeve portion, and the push ring directly presses the fluid pipe from the outer peripheral surface of the fluid pipe. A pipe joint structure, wherein an end edge portion is formed, and the inner end edge portion and an end edge of the sleeve portion on the front end side are configured to hold the fluid pipe in a retaining state. 2. A tubular joint main body which is formed integrally with the fluid device main body and has a receiving opening on the inner peripheral surface into which one end pushing portion of the fluid pipe is inserted, and a male screw portion on the outer peripheral surface. A pipe joint structure comprising: a resin sleeve portion formed in a receiving port of the joint body portion; and a push ring that can be screwed into an outer peripheral male thread portion of the joint body portion and that gives a sealing force by screwing, In a pipe joint structure in which an annular chamfer that is inclined to the inner peripheral surface of the fluid pipe is formed at the inner peripheral edge on the tip side of the sleeve portion, the inclination angle of the chamfer is 10 ° to 4 °.
It is set within the range of 8 °, and a bulging portion that bulges in the radial direction is formed on the sleeve portion, and an inner end edge portion that directly presses the fluid pipe from the outer peripheral surface of the fluid pipe is formed on the push ring. ,
A pipe joint structure, characterized in that the inner end edge portion and the end edge on the front end side of the sleeve portion are configured to hold the fluid pipe in a retaining state.