JP4324575B2 - Connection structure between flange pipes - Google Patents

Description

The present invention relates to a connection structure between flange pipes, and more specifically, a high purity liquid or ultrapure water piping system handled in manufacturing processes in various technical fields such as semiconductor manufacturing, medical / pharmaceutical manufacturing, food processing, chemical industry, etc. It is related with the connection structure for connecting the flange pipings used in the above.

Conventionally, as means for connecting flange pipes so that fluid can freely pass through their fluid passages, the first flange part of the first flange pipe which is one flange pipe and the other flange are used. In general, a structure is adopted in which the second flange portion of the second flange pipe, which is a pipe, is fastened and fixed using a plurality of bolts and nuts via a ring-shaped gasket therebetween. As such an example, those disclosed in Patent Document 1 and Patent Document 2 are known.

Incidentally, when connecting and connecting a flange pipe and a fluid device such as a pump or a valve, a connection structure according to the connection structure between the flange pipes described above is employed. That is, this is a connection structure in which the flange portion of the flange pipe and the end portion of the fluid supply / exhaust port portion of the fluid device are opposed to each other via a gasket, and both are tightened and connected by a bolt or the like.

In the connection structure described above, effective sealing performance is obtained by tightening the bolts until the predetermined surface pressure is reached between the pair of flange portions between which the gasket is sandwiched.
However, since the bolt tightening force decreases with time, it has been necessary to periodically perform additional tightening in order to prevent the tightening force from decreasing, that is, leakage from the connection portion due to torque reduction. When sealing with a gasket, a very high tightening force is required, so that the flange part of the flange piping needs to have high strength and is also disadvantageous in terms of workability for connecting and connecting. It was.

Further, in the connection structures disclosed in Patent Documents 1 and 2 described above, the inner diameter of the gasket is slightly larger than the diameter of the tubular fluid passage in the flange portion of the flange pipe or the flange portion of the fluid device. Since the unevenness exists, there is a possibility that a liquid pool is generated in the portion, which may cause an increase in the purity and the cleaning.
Japanese Patent Laid-Open No. 2000-120953 Japanese Patent Laid-Open No. 10-231969

The present invention has been made in view of such circumstances, and the object of the present invention is to devise a connection structure between flange pipes in a liquid piping system, so that retightening is hardly performed. An object is to maintain good sealing performance and to improve the assembly workability. Another object of the present invention is to achieve high purity by eliminating a liquid pool in the connecting portion.

In the invention according to claim 1, the tubular portion 1 is provided at the end of the tubular portion 1 </ b> A having the tubular fluid passage 4.
At the end of the first flange portion 1B of the first flange pipe 1 having a first flange portion 1B having a diameter larger than A and made of synthetic resin, and the end portion of the tubular portion 2A having the tubular fluid passage 4, the tubular portion 2A The second flange portion 2B of the second flange pipe 2 having a second flange portion 2B having a larger diameter and made of synthetic resin is interposed between the first flange portion 1B and the second flange portion 2B. In the connection structure of flange pipes that are connected in communication via a ring-shaped gasket G,
In the first flange portion 1B and the second flange portion 2B, annular protrusions 11 and 21 are formed on the outer diameter side portions of the fluid passages 4 and 4 that open to face each other in a facing manner.
The gasket G includes a fluid passage W formed to communicate the fluid passages 4 and 4 corresponding to the first and second flange portions 1B and 2B, and the first and second flange portions 1B and 1B.
2B includes a pair of annular grooves 51 and 51 formed in an outer diameter side portion of the fluid path W so as to be fitted to the annular protrusions 11 and 21 formed on the respective end surfaces of 2B. Composed of materials,
The first flange portion 1B and the second flange portion 2B are attracted to each other via the gasket G, and the annular protrusion 11 of the first flange portion 1B and the annular groove 51 at one end of the gasket G are formed. , And the annular protrusion 21 of the second flange portion 2B and the gasket G
Maintenance means I for maintaining the joined state in which the other end of the annular groove 51 is fitted to each other to form the fitting seal portion 3 is provided ,
In order to form the annular groove 51 in the gasket G on the inner and outer diameter sides of the annular projections 11 and 21 on the end surfaces of the first and second flange portions 1B and 2B, a projecting shape in the direction of the axis P
Formed are annular presser portions 12, 13, 22, and 23 that suppress or prevent the inner and outer peripheral wall end portions 52 and 53 formed from expanding and deforming due to the engagement between the annular groove 51 and the annular projections 11 and 21, respectively. And
The peripheral wall end portions 52, 53 and the annular pressing portions 12, 13, 22, 23 are configured to be pressed in the joined state to form the seal portion S2.
The annular presser portions 12, 13, 22, and 23 are arranged on the annular projection side so that valleys 14, 15, 24, and 25 surrounded by the annular projections 11 and 21 are constricted. The peripheral surface is inclined
Further, the peripheral wall end portions 52 and 53 are formed on the tapered peripheral surface 12a of the annular presser portions 12, 13, 22, and 23. The tapered peripheral surfaces 12a, 13a, 22a, and 23a are tapered portions. , 13a, 22a, 23a having tapered peripheral surfaces 52a, 53a that are formed into tapered annular protrusions that can enter the valleys 14, 15, 24, 25 in the joined state. The peripheral wall end portions 52 and 53 enter the valley portions 14, 15, 24, and 25 so that the tapered peripheral surfaces 12 a, 13 a, 22 a, 23 a, 52 a, and 53 a are pressed against each other. It is a feature.

According to a second aspect of the present invention, in the flange pipe-to-flange connection structure according to the first aspect, the cross-sectional shape of the gasket G is a center line along the axis P direction of the first and second flange portions 1B and 2B. Z and a center line X orthogonal to the center line Z are configured to have a substantially H-shape that is line symmetric with respect to the center line X.

According to a third aspect of the present invention, in the connection structure between flange pipes according to the first or second aspect, the maintaining means I draws the first flange portion 1B and the second flange portion 2B together, and It is characterized by being configured to exhibit a drawing function for obtaining a joined state.

According to a fourth aspect of the present invention, there is provided a connecting structure for connecting flange pipes according to the third aspect.
The maintaining means I has an outer diameter larger than that of the first flange portion 1B and the first and second
The first flanges interfere with the first flange portion 1B in the direction of the axis P of the flange pipes 1 and 2.
A first split-type ring 35 that is externally fitted to the tubular portion 1A of the pipe 1;
The passage of the first flange portion 1B is allowed, and the first split ring 35 is the axis.
An inward flange 34 having an opening 34a that interferes in the P direction is formed at one end; and
A cylindrical bolt 32 having a male screw portion 32n formed on the outer periphery of the other end;
The second flange portion 2B has an outer diameter larger than that of the second flange portion 2B, and the second flange portion 2B extends in the axis P direction.
A second split mold that is fitted onto the tubular portion 2A of the second flange pipe 2 so as to interfere with the lunge portion 2B.
Ring 35;
The passage of the second flange portion 2B is allowed, and the second split ring 35 is the axis.
An inward flange 34 having an opening 34a that interferes in the P direction is formed at one end; and
A cylindrical nut having a female screw portion 33n that can be screwed into the male screw portion 32n on the inner periphery of the other end portion.
33,
The cylindrical bolt 32 and the cylindrical shape obtained by screwing the male screw portion 32n and the female screw portion 33n.
By the tightening operation with the nut 33, the first flange portion 1B and the second flange portion 2B are mutually connected.
What is configured to be drawn through the gasket G
It is.

According to a fifth aspect of the present invention, there is provided a connecting structure for connecting flange pipes according to the third aspect.
The maintaining means I is one of the first flange portion 1B and the second flange portion 2B.
A cylindrical nut 5 having a female screw portion 5n that can be screwed into a male screw portion 1n formed on the outer peripheral portion;
The first and second flanges on either the first flange portion 1B or the second flange portion 2B
The first flange portion 1B and the second flange portion so as to interfere with each other in the direction of the axis P of the portions 1B and 2B
2B and a split ring 35 fitted on the other tubular portion 2A.
One end of the cylindrical nut 5 has the first flange portion 1B and the second flange portion 2B.
One of the other passages is allowed and interferes with the split ring 35 in the direction of the axis P.
An inward flange 6 having an opening 6a is formed,
By the tightening operation of the cylindrical nut 5 to the male thread 1n, the first flange 1
B and the second flange portion 2B are constructed so as to be attracted to each other via the gasket G.
It is characterized by being.

According to a sixth aspect of the present invention, there is provided a connecting structure for connecting flange pipes according to the third aspect.
The maintenance means I is provided on either the first flange portion 1B or the second flange portion 2B.
Through holes 1h and 2h to be formed, and the first flange portion 1B through the through holes 1h and 2h.
And a bolt that is screwed into a nut portion 42 provided on the other of the second flange portion 2B and the second flange portion 2B.
And 41.
The first flange is formed by screwing and tightening the bolt 41 to the nut portion 42.
The part 1B and the second flange part 2B are attracted to each other via the gasket G.
It is comprised by these.

The invention according to claim 7 is characterized in that, in the connection structure between flange pipes according to claim 4 or 5, it comprises at least one of the following configurations (a) and (b). is there.
(B) The inward flange 34 of the cylindrical bolt 32 and / or the cylindrical nuts 33, 5
, 6 are adjacent to the inner peripheral surface portions 32m, 33m, 5m of the split ring inner fitting portion.
It is formed on a flat inner peripheral surface concentrically with the passage 4, and the inner peripheral surface portions 32m, 33m, 5m.
The inner diameter of the split ring 35 and the outer diameter of the split ring 35 formed in a rectangular cross section are formed to have substantially the same diameter.
Yes.
(B) The outer diameter part of the tubular parts 1A and 2A to which the split ring 35 is fitted is the flow of the tubular part.
It is formed on the flat outer peripheral surface 2k concentrically with the body passage 4, and the outer diameter of the outer peripheral surface 2k and the front
The inner diameter of the split ring 35 is formed to be substantially the same diameter.

According to an eighth aspect of the present invention, in the connection structure between flange pipes according to any one of the first to seventh aspects, the gasket G is formed of a fluororesin.

The invention according to claim 9 is the connection structure between flange pipes according to any one of claims 1 to 8, wherein the first and second flange portions 1B, 2B are formed of a fluororesin. It is a feature.

According to the first aspect of the present invention, the annular projections formed on the first and second flange portions, respectively,
The annular grooves formed on the one end face and the other end face of the sket are respectively moved relative to each other in the axial direction.
Are fitted to each other to form a fitting seal portion.
Even if there is a crack, the fitting state between the annular protrusion and the annular groove is maintained, and between the first and second flange portions
It is possible to continue to exhibit excellent sealing properties that prevent liquid leakage. For example, made of semiconductor
If such a connection structure is used in the piping system of the cleaning device in a manufacturing facility, good sealing performance is achieved.
While it can be secured, the area occupied by the device can be reduced, which is advantageous in terms of cost and a large flow path is secured.
Can increase the circulation flow rate and increase the purity of chemicals, thereby contributing to yield improvement.
It is possible to achieve the effect of.

Then, by the maintaining means, the two flange portions are attracted to each other via the gasket.
Can maintain a good joined state, ensuring good sealing without leakage between flange pipes
Can be maintained over a long period of time, and the connection structure between flange pipes is excellent in reliability.
Can provide build-in. As a result, good sealing performance can be maintained with little additional tightening.
Providing a connection structure between flange pipes that can be held and improved in assembly workability
can do.

By the way, in the fitting structure with convexes inserted into the recesses, both of these are made of the same material.
Even if it is, the convex member hardly changes (compression deformation), and the concave member expands and deforms.
It is generally known that it tends to be easy. Therefore, in the first aspect of the present invention, each flange
An annular projection that is convex on the part and an annular groove that is concave on the gasket are formed.
Therefore, it is a small part that deforms due to creep or aging.
Gasket side and flange piping side is hardly deformed.
The advantage that good sealing performance can be maintained over a long period of time can be obtained by reasonable means.
There is also an effect.

According to the first aspect of the invention, the following operational effects are obtained. As mentioned above
Since the concave side tends to spread and easily deform, that is, in the present invention, it forms an annular groove.
This means that the inner and outer peripheral wall ends formed in the gasket expand and deform.
. Therefore, the annular presser portions that suppress or prevent the expansion deformation of the end portion of the peripheral wall are provided with the first and second flanges.
Since it is formed in the lunge, the expansion deformation at the end of the peripheral wall is eliminated or reduced, and the annular protrusion and ring
The groove can be mated with a strong pressure contact force, and an excellent sealing function is achieved by mating these two.
Can be demonstrated as expected.

Moreover, the lack of rigidity at the end of the peripheral wall can be compensated for by the presence of the annular pressing portion.
Therefore, it is possible to reduce the thickness of the peripheral wall end of the gasket compared to the case where these are not present.
Therefore, it is possible to reduce the overall width of the fluid passage by reducing the width of the gasket.
Ri also has the advantage that it can be made compact as a connection structure between flange pipes.

According to the invention of claim 1, in the joined state, the annular protrusions of the first and second flange portions and
Since a seal portion is formed by pressure contact with the annular groove on one end surface or the other end surface of each gasket,
As a result, a mating seal part with higher sealing performance is constructed, and a flat seal with excellent sealing performance.
Can be connected to each other.

According to the invention of claim 1, in the joined state, the annular protrusions of the first and second flange portions and
The first and second inner diameter sides and the outer diameter side of the fitting portion with the annular groove on one end surface or the other end surface of each gasket
And the taper peripheral surface of the second flange portion and the taper peripheral surface of the gasket are in pressure contact with each other.
In addition, the contact between the tapered peripheral surfaces makes it possible to obtain both effects of reducing the size of the connection structure and improving the sealing performance.

In addition, since the tapered peripheral surfaces are brought into contact with each other, there is an advantage that the pressure contact force increases as the flange pipe and the gasket are strongly pressed, and the effects of downsizing and improving the sealing performance can be further enhanced. Further, it is possible to provide a connection structure in which no liquid pool is generated between the tapered peripheral surfaces.

According to the invention of claim 2, the gasket has a substantially H-shaped cross section that is symmetrical in the vertical and horizontal directions.
Because it is formed, for example, in the gasket and the part fitted with it compared to the asymmetrical one
Design and manufacture of certain first and second flange parts is facilitated and fitted to flange piping
The balance (strength balance, assembly balance) can be improved.

According to the invention of claim 3, the maintaining means determines the joined state between the first flange portion and the second flange portion.
Not only to maintain, but also to bring the first flange part and the second flange part together to obtain a joined state
The pulling function can also be demonstrated, so there is no need to prepare other pulling means, and as a whole
There is an advantage that it is possible to omit the assembling work and to reduce the cost.

According to the invention of claim 4, the first and second split rings that are fitted on the respective tubular portions are used to
Cylindrical bolts equipped on the 1 flange piping side and cylindrical nuts equipped on the 2nd flange piping side
By simply operating and tightening, the annular projections on the first and second flanges and the gas
By fitting the annular groove of the ket, the first and second flange portions are connected to each other, that is, the first and second flanges.
The pipes can be connected in communication. And the screwing of the cylindrical bolt and the cylindrical nut
Convenient and easy-to-handle withdrawing function that can maintain the joined state just by stopping
Means are obtained as a reasonable and space-saving means.

Further, since a pair of split rings, a cylindrical bolt, and a cylindrical nut are used, each flange portion does not need a configuration for connection such as forming a screw, and the first and second flange portions It is also preferable that the flanges can be made common and inexpensive, such as making them the same.

In addition, cylindrical bolts and nuts can be freely fitted and removed from the corresponding flanges.
In the external fitting state, the cylinder interferes with the corresponding flange part via the split ring in the axial direction.
While enabling direct connection between the first and second flanges using a cylindrical bolt and a cylindrical nut,
The split ring, cylindrical bolt, and cylindrical nut can be retrofitted to the first and second flange pipes.
Is.

Pressurized forte, can be transmitted to the first and second flange portions ensuring a clamping force between the tubular bolt and the cylindrical nut with a reasonable that requires less number of components. Therefore, a cylindrical bolt, a cylindrical nut, and a pair of a cylindrical bolt and a cylindrical nut can be used without taking the difficult manufacturing method of fitting a cylindrical bolt or a cylindrical nut to a corresponding tubular part when manufacturing the first and second flange pipes. Connection with flange pipes is easy and convenient using split ring.

According to the invention of claim 5 , the cylindrical nut engaged with one of the first and second flange portions via the split ring is screwed into the other male screw of the first and second flange portions. By simply operating, the annular projections of the first and second flange portions and the annular groove of the gasket can be fitted to connect the flange pipes in a sealed state, and the cylindrical nut can be screwed. Convenient and easy-to-handle maintenance means with a pulling function that can maintain the connection state by simply stopping is obtained as a compact and space-saving rational means.

Further, the cylindrical nut can be externally fitted and detached at the end of the first flange portion or the second flange portion, and in the externally fitted state, it can be attached to both the first flange portion or the second flange portion and the split ring. Since interference occurs in the axial direction, the split ring and the cylindrical nut can be retrofitted to the first or second flange portion while allowing direct connection between the first and second flange portions by the cylindrical nut. . Therefore, the cylindrical nut is fitted on the first or second flange portion during the production of the first or second flange pipe while making the economical and reasonable number of parts as small as the cylindrical nut and split ring. The connection operation between flange pipes can be performed easily and conveniently using a cylindrical nut without taking the difficult manufacturing method of attaching.

According to invention of Claim 6 , if a through-hole is formed in one of the 1st and 2nd flange parts, the bolt which lets the through-hole pass, and the nut part formed in the other of the 1st and 2nd flange parts, It is possible to draw and maintain the two flange pipes by a simple means simply by providing the two. That is, it is possible to provide a connection structure between flange pipes having various advantages while being a simple and inexpensive maintenance means with a drawing function using bolts and nuts.

According to the seventh aspect of the present invention, (a) a portion adjacent to the inward flange at the inner back portion of the inner diameter portion of the cylindrical bolt or cylindrical nut is formed on the flat inner peripheral surface portion concentric with the tubular fluid passage. And a configuration in which the inner diameter of the inner peripheral surface portion and the outer diameter of the split ring formed in a rectangular cross section are formed to have substantially the same diameter, and (b) the outer portion of the tubular portion in which the split ring is fitted. At least one of the configuration in which the diameter portion is formed on the flat outer peripheral surface concentrically with the fluid passage of the tubular portion, and the outer diameter of the outer diameter portion and the inner diameter of the split ring are formed to have substantially the same diameter. Therefore, when the cylindrical nut is screwed, the split ring is in a state of being tilted, or the axial flange is pushed to the first flange portion or the second flange portion by the screwing of the cylindrical nut. It is possible to reduce the problem of pressure not being transmitted well It can, be able to effectively press the flanges each other, an advantage that can cause well attracting the direction approaching the flange portions to each other to each other is obtained. In particular, if both (A) and (B) are provided, the above-mentioned problems can be prevented, and the above-described effects can be further enhanced.

According to the inventions of claims 8 and 9 , since the gasket and both flange portions are formed of a fluorine-based resin having excellent chemical resistance and heat resistance, the fluid is a chemical solution or a chemical liquid. In addition, even if it is a high-temperature fluid, the connecting structure portion is not deformed and is not easily leaked, and a good sealing property can be maintained. The fluororesin is a resinous substance obtained by polymerization of ethylene and derivatives thereof in which one or more hydrogen atoms are substituted with fluorine,
Stable at high temperatures and excellent in water repellency. Further, it is preferable in that it has a small coefficient of friction, extremely high chemical resistance, and high electrical insulation.

Embodiments of a connection structure between flange pipes according to the present invention will be described below with reference to the drawings. 1 to 5 are a side view showing a connection structure between flange pipes according to the first embodiment, a cross-sectional view of main parts, an assembly procedure diagram, an exploded cross-sectional view of main parts showing a gasket structure, and a configuration of a fitting seal part. It is sectional drawing of the principal part shown. Moreover, FIGS. 6-10 is sectional drawing etc. of the principal part which shows the connection structure of the flange piping by Examples 2-5.

[Example 1]
As shown in FIG. 1, the flange pipe connection structure according to the first embodiment has a first flange having a circular shape and a circular section at the end of a tubular portion 1A having a circular fluid passage 4. The first flange pipe 1 made of a fluororesin (an example of a synthetic resin) such as PTFE having the portion 1B
A fluororesin (such as PTFE) such as PTFE having a flange portion 1B and a second flange portion 2B having a larger diameter and a circular cross section than the tubular portion 2A at the end portion of the tubular portion 2A having the tubular fluid passage 4. Example) Between flange pipes that are connected to each other through a ring-shaped gasket G that is interposed between the first flange part 1B and the second flange part 2B. It is configured as a connection part.

In the first embodiment, the first flange pipe 1 and the second flange pipe 2 are identical to each other and have a common shaft center P. As shown in FIG. And the second flange portion 2B are connected in a sealed state via a ring-shaped gasket G sandwiched between them. The two flange portions 1B and 2B are attracted to each other via the gasket G by the maintaining means I having a attracting function, and the first flange portion 1 is attracted by this attracting action.
Between the first seal end t1 formed on the end face of B and one end face of the gasket G, and between the second seal end t2 formed on the end face of the second flange part 2B and the other end face of the gasket G Thus, the fitting seal part 3 is formed by fitting with each other, and the joined state in which the fitting seal part 3 is formed is maintained.

In the connection part between both flange pipes 1 and 2 shown in FIG. 2, the first seal end t1 formed on the end face of the first flange part 1B and the second seal formed on the end face of the second flange part 2B. Since the end portion t2 has the same structure, only the first seal end portion t1 will be described, and the second seal end portion t2 will be denoted by the same or corresponding symbol, and the description thereof will be omitted. The first seal end t <b> 1 has an annular protrusion 11 formed concentrically with the fluid passage 4 on the outer diameter side portion of the opening end of the fluid passage 4 on the end face of the first flange portion 1 </ b> B that opens the fluid passage 4. It is configured. The first seal end t1 is formed between the annular pressing protrusions 12 and 13 formed inside and outside the annular protrusion 11 and between these annular pressing protrusions (an example of the annular pressing portion) 12 and 13 and the annular protrusion 11. It has deep valleys 14 and 15 that are constricted.

As shown in FIGS. 2 to 5, the gasket G is formed in a ring shape made of a fluororesin such as PFA or PTFE having a tubular fluid path W and a pair of left and right annular grooves 51, 51. Yes. The fluid path W is a place where the fluid passage 4 of the first flange pipe 1 and the fluid passage 4 of the second flange pipe 2 communicate with each other, and the inner diameter r3 of the fluid path W is mutually equal to the inner diameters r1 and r2 of the fluid passages 4 and 4. The same diameter is formed. The pair of annular grooves 51, 51 includes first and second flange portions 1B,
It is formed in a groove that can be fitted into each of the annular protrusion 11 of the first seal end t1 and the annular protrusion 21 of the second seal end t2 formed on the end surface of 2B.

The cross-sectional shape of the gasket G includes a pair of left and right annular grooves 51, 51 and the annular grooves 51, 51.
And an inner peripheral wall 54 and an outer peripheral wall 55 for forming a pair of annular grooves 51, 5
1 is symmetrical with the same depth and width, and the inner and outer peripheral walls 54 and 55 are also symmetrical with each other, and the longitudinal center along the axis P direction of the first and second flange pipes 1 and 2. About H which becomes line symmetric (substantially line symmetric) with respect to both Z and the horizontal center line X orthogonal to the vertical center line Z
It is formed in a shape. The left and right end portions of the inner peripheral wall 54 are formed as tapered inner peripheral surfaces 52a and 52a in which the left and right end portions of the fluid path W, which is the inner peripheral surface 54a, are inclined outwardly in a bulging shape. The part is also formed on tapered outer peripheral surfaces 53a, 53a in which left and right end portions of the outer peripheral surface 55a are inclined inward.

The annular protrusion 11 of the first seal end t1 in the first flange portion 1B of the first flange pipe 1
And the annular presser protrusions 12, 13, 22, 23 are formed on the inner and outer diameter sides of the annular protrusion 21 of the second seal end t2 in the second flange portion 2B of the second flange pipe 2. . The inner and outer annular seal protrusions 52 and 53 formed so as to protrude in the axial center P direction so as to form the annular groove 51 in the gasket G are expanded and deformed by the engagement between the annular groove 51 and the annular protrusions 11 and 21. It has a role of preventing good performance and exerting good sealing performance.

The structure related to the annular pressing protrusion will be described with respect to the gasket G and the upper first seal end t1. As shown in FIG. 5, the inner and outer annular pressing protrusions 12 and 13 are symmetrical, and the valley protrusions 14 and 15 surrounded by the annular protrusion 11 and the annular protrusion 11 on the annular protrusion side so as to be constricted. The side peripheral surface is formed into a tapered annular protrusion having a tapered outer peripheral surface 12a and a tapered inner peripheral surface 13a. That is, the first seal end t1 is a general term for the annular protrusion 11 and the annular pressing protrusions 12 and 13 and the valley portions 14 and 15 formed on both the inside and outside of the annular protrusion 11.

The left end portions (the left in FIG. 5) of the peripheral walls 54 and 55 inside and outside of the gasket G are annular presser protrusions 1.
2 and 13 tapered outer peripheral surfaces 12a and tapered inner peripheral surfaces 52a, tapered inner peripheral surfaces 52a and tapered outer peripheral surfaces 53a, respectively, and tapered annular seal protrusions 52 that can enter 14 and 15 freely. 53. In the joined state (see FIG. 1), the annular seal protrusions 52 and 53, which are the left end portions of the inner and outer peripheral walls 54 and 55, enter the corresponding valley portions 14 and 15, and the tapered outer peripheral surface of the first seal end portion t1. 12a and the taper inner peripheral surface 52a of the gasket G are press-contacted, and the taper inner peripheral surface 13a of the first seal end t1 and the taper outer peripheral surface 53a of the gasket G are press-contacted.

That is, at the left end of the gasket G, an annular groove 51 and annular seal protrusions 52, 5 inside and outside thereof are provided.
3, a left seal portion g1 is formed, and similarly, a right seal portion g2 is formed at the right end portion. The left seal part g1 is fitted with the first seal end part t1 to form the fitting seal part 3, and the right seal part g2 is fitted with the second seal end part t2 to form the fitting seal part 3.

The fitting structure of the fitting seal portion 3 will be described in detail with respect to the first seal end t1 and the left seal portion g1 of the gasket G. As shown in FIGS. The inner and outer annular seal protrusions 52 and 53 are symmetrical to each other, and are not between the included angle α ° of the entire inner and outer valley portions 14 and 15 and the sharp angle β ° of the entire inner and outer annular seal protrusions 52 and 53. , Α ° <β ° is set. Preferably, the relationship α ° + (5 to 15 °) = β ° is set. With this configuration, in the joined state (described later) in which the annular protrusion 11 and the annular groove 51 of the first seal end t1 are fitted, the inner annular holding protrusion 12 and the inner annular seal protrusion 52 are tapered outer peripheral surfaces 12a. And the taper inner peripheral surface 52a are brought into pressure contact with each other at the innermost diameter side portion (see the phantom line in FIG. 5), and the fluid passing through the fluid passage W enters between the outer taper peripheral surfaces 12a and 52a. The advantage of functioning as the secondary seal portion S2 that also prevents this is obtained.

The relationship d1> d2 is set between the width d1 of the first annular protrusion 11 and the width d2 of the left annular groove 51, and preferably d1 × (0.6 to 0.8) = d2. It is good to set it as a relationship. A relationship of h1 <h2 is set between the protruding length h1 of the first annular protrusion 11 and the depth h2 of the left annular groove 51. With these configurations, the first annular protrusion 11 and the left annular groove 51 are specifically formed between the inner and outer peripheral surfaces of the first annular protrusion 11 and the inner and outer side peripheral surfaces of the left annular groove 51 corresponding to each other. A primary seal portion S1 is formed that is strongly pressed and exhibits excellent sealing performance that prevents fluid leakage, and the tapered outer peripheral surface 12a of the inner annular presser protrusion 12 is formed.
And the taper inner peripheral surface 52a of the inner annular seal protrusion 52 are always in contact with each other, and there is an advantage that the above-described secondary seal portion S2 is favorably formed.

Further, the tip of the inner annular presser protrusion 12 and the tips of the annular seal protrusions 52 and 53 are cut so as not to have pin angles, that is, the inclined cut surface 12b and the cut surfaces 52b and 5.
It is formed in 3b. With these configurations, even if the tip of the inner annular presser protrusion 12 spreads slightly toward the fluid passage W and is deformed, the fluid passage W
A recess having a triangular cross-section opened in the middle becomes possible, and the fluid existing in the recess can easily flow out, so that a liquid pool is not substantially generated. In addition, the opening angle of the recess, that is, the included angle between the inclined cut surface 12b and the tapered inner peripheral surface 52a is sufficiently large, and the possibility of liquid accumulation due to surface tension is avoided. Further, the inner and outer corners of the tip of the annular protrusion 11 have a chamfered cut shape 11a, so that the press-fitting movement into the narrow annular groove 51 can be smoothly performed without inconvenience such as galling.

In the state where the outer annular presser protrusion 13 continues to the taper inner peripheral surface 13a of the annular presser protrusion 13,
An inner peripheral wall portion 1b into which the outer peripheral wall 55 of the gasket G can be inserted is formed continuously, and the overall shape of the inner annular presser protrusion 12 is different. And also about the 2nd seal end t2,
There is an inner peripheral wall portion 2b into which the outer peripheral wall 55 of the gasket G can be inserted in a state following the taper inner peripheral surface 23a of the annular presser protrusion 23. Again, the inner annular presser protrusion 22 has an overall shape. Different. The first and second inner peripheral wall portions 1b and 2b function as a guide when the left and right seal portions g1 and g2 of the gasket G are fitted to the first and second seal end portions t1 and t2, and the inside of the taper. The function of preventing the outer peripheral wall 55 of the gasket G from spreading and deforming together with the peripheral surfaces 13a and 23a can also be exhibited.

In addition, if the ring-shaped attachment / detachment flange f which protrudes an outer diameter is integrally formed in the outer peripheral wall 55 of the gasket G as shown by the phantom line in FIG. 4, the gasket G from the 1st or 2nd flange part 1B, 2B will be demonstrated. There is an advantage that when removing the, the detachable flange f can be easily removed by pulling it with a tool or fingers. In this case, the thickness of the detachable flange f is set to a value smaller than the gap between the first and second flange portions 1B and 2B in the joined state.

Next, the maintenance means I will be described. As shown in FIGS. 1 to 3, the maintaining means I extends over the first and second flange pipes 1 and 2, and the first flange portion 1 </ b> B and the second flange portion 2 </ b> B are mutually connected via a gasket G. It is configured to be able to exhibit a pulling function that draws in the approaching direction and maintains the drawn state. Both flanges 1 by means of maintenance means I
When B and 2B are drawn toward each other via the gasket G, first, the annular protrusions 11 and 21 and the respective annular grooves 51 are fitted, and most of them are fitted, and then the annular presser is engaged. Protrusion 12
, 13, 22, 23 and the annular seal projections 52, 53 come into contact with each other.

And each taper inner peripheral surface 13a, 52a, 23a and each taper outer peripheral surface 12a, 53a, 2
In the state where the two flange portions 1B and 2B stop moving in close contact with 2a, the annular projection 11 and each annular groove 51 are located in the direction of the axis P and within the end face of the first flange portion 1B. Perimeter wall 1
A gap is set between the outer diameter portion 1g from b and the outer diameter portion 2g from the inner peripheral wall portion 2b of the end face of the second flange portion 2B. That is, each taper inner peripheral surface 13a, 52a,
23a and each outer peripheral surface 12a, 53a, 22a so that the outer diameter portion 1g,
A gap is provided between 2 g. Thereby, an effective sealing function in the primary and secondary seal portions S1 and S2 in the fitting seal portion 3 by fitting the annular protrusions 11 and 12 and the annular groove 51 is obtained, and in the secondary seal portion S2 The liquid can be allowed to flow in a clean state between the fluid passages 4 and 4 and the fluid passage W having the same diameter without any gaps and no liquid accumulation.

Now, the maintaining means I includes two sets of split rings 35, 35, a cylindrical bolt 32, and a cylindrical nut 33.
It consists of a total of four parts. The first split ring 35 fitted on the first flange pipe 1 has an outer diameter larger than that of the first flange portion 1B, and the first and second flange pipes 1, 2
It is fitted on the tubular portion 1A of the first flange pipe 1 so as to interfere with the first flange portion 1B in the axial center P direction, and is constituted by a split ring that is divided into two or more than three. .
In the cylindrical bolt 32, an inward flange 34 having an opening 34a that allows passage of the first flange portion 1B and interferes with the first split ring 35 in the axial center P direction is formed at one end portion. And it is comprised by the cylindrical volt | bolt by which the external thread part 32n is formed in the outer periphery of an other end part.

The second split ring 35 fitted on the second flange pipe 2 has an outer diameter larger than that of the second flange portion 2B, and is second to interfere with the second flange portion 2B in the axis P direction. It is fitted on the tubular portion 2A of the flange pipe 2, and is constituted by a split ring that is divided into two or more than three. The second split ring 35 is the same component as the first split ring 35. In the cylindrical nut 33, an inward flange 34 having an opening 34a that allows passage of the second flange portion 2B and interferes with the second split ring 35 in the axial center P direction is formed at one end portion. And it is comprised by the cylindrical nut by which the internal thread part 33n which can be screwed together by the external thread part 32n is formed in the inner periphery of an other end part. That is, the diameter of the cylindrical nut 33 is larger than the diameter of the cylindrical bolt 32. Then, the first flange portion 1B and the second flange portion 2B attach the gasket G to each other by tightening the cylindrical bolt 32 and the cylindrical nut 33 by screwing the male screw portion 32n and the female screw portion 33n. It is constructed so that it can be pulled in the direction of approaching through, and the drawing state can be maintained (see FIG. 3).

The opening 34a of the inward flange 34 of the cylindrical bolt 32 and the cylindrical nut 33 is set to a minimum inner diameter dimension sufficient to allow passage of the flange portions 1B and 2B. The outer diameter of each split ring 35 is set to be slightly smaller than the inner diameter of the inner diameter portion 32a so that it can enter the inner diameter portion 32a of the cylindrical bolt 32. It is set to a minimum dimension that allows it to be externally fitted to 2A. Inward flange 3 in the cylindrical nut 33
4 is formed with a female thread portion 33n and an inner peripheral surface portion 33m having a smaller diameter than the inner diameter portion 33a connected therewith in order to closely fit the second split ring 35 therein.

The portion adjacent to the inward flange 34 in the inner diameter portion 32a of the cylindrical bolt 32 has a first
An inner peripheral surface portion 32m that is slidable in the axial direction on the split ring 35 and has a length in the axial center P direction that covers the width dimension of the first split ring 35 is flat and concentric with the fluid passage 4. It is formed on the peripheral surface. Further, the inner peripheral surface portion 33 m of the cylindrical nut 33 described above is also formed on a flat inner peripheral surface concentric with the fluid passage 4. That is, the inner peripheral surface portion 32m, which is the inner back portion of the inner diameter portion 32a of the cylindrical bolt 32, is formed on a flat inner peripheral surface concentric with the fluid passage 4, and the inner diameter of the inner peripheral surface portion 32m has a rectangular cross section. While the fitting tolerance is set slightly larger than the outer diameter of the formed first split ring 35, the inner peripheral surface portion 33m of the cylindrical nut 33 is a flat outer peripheral surface concentric with the fluid passage 4. In addition, the inner peripheral surface portion 33m is dimensionally set in a fitting tolerance state in which the inner diameter of the inner peripheral surface portion 33m is slightly larger than the outer diameter of the first split ring 35 formed in a rectangular cross section. In addition, the inner diameter of each split ring 35 is set to be approximately the same as the diameter of the root of each flange portion 1B, 2B in each tubular portion 1A, 2A so as to come into surface contact with each flange portion 1B, 2B.

As a result, when the cylindrical bolt 32 and the cylindrical nut 33 are screwed together and the cylindrical bolt 32 and the cylindrical nut 33 are screwed, the split rings 35 and 35 are tilted. Or the pressing force in the axial center P direction due to the screwing of the first and second cylindrical bolts 32 and the cylindrical nut 33 is not transmitted to the flange portions 1B and 2B. The flange portions 1B and 2B can be effectively pushed and the flange portions 1B and 2B can be satisfactorily pulled toward each other. That is, the inner peripheral surface portions 32 m and 33 m of the split ring inner fitting portion adjacent to the inward flange 34 of the cylindrical bolt 32 and the cylindrical nut 33 are formed on the flat inner peripheral surface concentric with the tubular fluid passage 4. The inner diameters of the inner peripheral surface portions 32m and 33m and the outer diameter of the split ring 35 formed in a rectangular cross section are larger than the outer diameter of the split ring 35. Are formed to have substantially the same diameter.

The operation procedure for connecting and connecting the two flange portions 1B and 2B using the maintenance means I is as follows. First, as shown in FIG. 3A, the cylindrical bolt 32 is fitted on the outer periphery of the tubular portion 1A of the first flange pipe 1 through the outer diameter side of the first flange portion 1B, and the tube Nut 33
Is fitted to the outer periphery of the tubular portion 2A of the second flange pipe 2 through the outer diameter side of the second flange portion 2B. The cylindrical bolt 32 and the cylindrical nut 33 are the first and second flange portions 1B and 2B, respectively.
Therefore, even when the other ends of these flange pipes 1 and 2 are already connected to a fluid device or the like, each tubular portion 1 can be passed from the end on the flange portion 1B or 2B side without any problem.
A and 2A can be externally fitted. If a hexagonal part or a two-sided width part for turning with a spanner tool or the like is formed at the inward flange side ends of the cylindrical bolt 32 and the cylindrical nut 33, it is convenient for tightening and disassembling operations. It is.

Next, as shown in FIG. 3 (b), the first split ring 35 is passed through between the first flange 1B and the tip of the cylindrical bolt 32 and in contact with the side surface of the first flange portion 1B. The second split ring 35 is fitted to the outer periphery of the tubular portion 1A of the flange pipe 1 and the second flange 2B.
And is fitted to the outer periphery of the tubular portion 2A of the second flange pipe 2 so as to contact the side surface of the second flange portion 2B. At this time or before the gasket G
May be attached to one of the first and second seal end portions t1 and t2 through provisional fitting between the annular projections 11 and 21 and the annular groove 51. Next, both flange portions 1B are passed through the gasket G.
, 2B, and a tightening operation [see FIG. 3 (c)] in which the cylindrical bolt 32 and the cylindrical nut 33 are screwed together in this state, the joined state shown in FIGS. can get.

The first flange pipe 1 and the second flange pipe 2 are drawn toward each other by the maintaining means I. As shown in FIG. 2, in the joined state, the gasket G is formed by both flange portions 1B and 2B. Is clamped. Further, as described above, both flange portions 1B,
Each of the annular protrusions 11 and 21 of 2B and the annular grooves 51 on both left and right ends of the gasket G are press-fitted to form a primary seal portion S1, and each tapered inner peripheral surface 13a, 52a, 23a and each tapered outer periphery are formed. By forming the secondary seal portion S2 by pressure contact with the surfaces 12a, 53a, 22a, between the fluid passage 4 of the first flange pipe 1, the fluid path W of the gasket G, and the fluid passage 4 of the second flange pipe 2. The fitting seal portions 3 and 3 exhibiting a good sealing function of allowing the liquid to flow without leakage and liquid accumulation are formed.

By the way, as shown in FIG. 2, the outer diameter portion of the second tubular portion 2A where the second split ring 35 is fitted is formed on the flat outer peripheral surface 2k concentrically with the tubular fluid passage 4, and The outer diameter of the outer peripheral surface 2k and the inner diameter of the second split mold ring 35 are formed to have substantially the same diameter in a region where the inner diameter of the split ring 35 is larger than the outer diameter of the outer diameter portion 2k. This is more convenient. If this configuration is adopted, the second split ring 35 and the second ring 35 can be connected to the second nut 35 when the cylindrical nut 33 is tightened.
The tubular portion 2A can smoothly move relative to each other without being bent, and the function of efficiently performing the pulling movement of the both fluid supply / discharge port portions 1B and 2B by the maintaining means I is promoted. When combined with a fitting structure having a fitting tolerance between the inner peripheral surface portion 33 m of the cylindrical nut 33 and the outer peripheral surface of the second split ring 35, the second is caused by the screwing of the cylindrical bolt 32 and the cylindrical nut 33. The follow-up movement of the split ring 35 is further smoothed, and the connection means can be firmly connected without leakage while the maintenance means I is lightly operated.
Naturally, the above configuration can be applied to the first split ring 45 and the cylindrical bolt 32 in the first fluid device 1.

[Example 2]
FIG. 6 shows a connection structure between flange pipes according to the second embodiment. This is different from the first embodiment only in the maintenance means I, and the maintenance means I having the first separate structure will be mainly described. As shown in FIG. 6, the first different structure maintaining means I includes a first flange portion 1B having a first male screw 1n formed on the outer peripheral portion and a second flange having the same diameter as the first male screw 1n on the outer peripheral portion. The second flange portion 2B is provided with a male screw 2n, and a cylindrical nut 7 having a female screw 7n that can be screwed to the male screws 1n and 2n.

The cylindrical nut 7 is formed with an inner peripheral portion 7a having a diameter larger than the male screws 1n and 2n between the female screw 7n on the distal end side and the inward flange 8 on the proximal end side. The flange 8 has an axis P
It is formed to have an inner diameter that interferes with the flange portions 1B and 2B in the direction. In the assembled state shown in FIG. 6, the second male screw 2n of the second flange portion 2B is accommodated in the turn inner peripheral portion 7a,
Only the first male screw 1n and the female screw 7n of the first flange portion 1B are screwed together, whereby the first and second flange portions 1B and 2B are connected to each other, that is, the first and second flange pipes. The state in which 1 and 2 are attracted to each other is maintained.

To assemble, first, the female screw 7n of the cylindrical nut 7 is attached to the second male screw 2 of the second flange portion 2B.
The second male screw 2n is passed through to be rotatably accommodated in the inner peripheral portion 7a. The female screw 7n is screwed into the screw 1n and tightened. Then, the cylindrical nut 7 is the second flange portion 2B.
Therefore, only the first flange portion 1B is screwed by tightening, and as a result, the first flange pipe 1 and the second flange pipe 2 are attracted, and the gasket G Thus, a joined state in which the fluid passages 4 and 4 are connected in a sealed state is maintained.
That is, the maintenance means I having the first separate structure is also configured to have a drawing function.

Example 3
FIG. 7 shows a connection structure between flange pipes according to the third embodiment. This is different from the first embodiment only in the maintaining means I, and the second different structure maintaining means I will be described. The maintaining means I having the second separate structure includes the maintaining means I shown in FIG. 2 and the maintaining means I having the first separate structure shown in FIG.
As shown in FIG. 7, the first flange portion 1B has a first male screw 1n formed on the outer peripheral portion and the same diameter as the first male screw 1n on the outer peripheral portion. The second flange 2B in which the second male screw 2n is formed, a cylindrical nut 5 having a female screw 5n that can be screwed to both the male screws 1n, 2n, and a split ring 35.

The cylindrical nut 5 is formed with an inner peripheral portion 5a having a diameter larger than the male screws 1n and 2n between the female screw 5n on the distal end side and the inward flange 6 on the proximal end side. The flange 6 has an axis P
It is formed to have an inner diameter portion 6a that does not interfere with the flange portions 1B and 2B in the direction. The split ring 35 may have a two-part structure as shown in FIG. 3 or a circular ring divided into three or more pieces (eg, consisting of three fan-shaped members of less than 120 degrees). Yes,
Passing over the inward flange 6 and the female screw 5n and turning from the outside into the inner peripheral part 5a,
In addition, the ring-shaped inner peripheral portion 5a can be assembled into a ring shape. Further, the split ring 35 can be configured by a single C-shaped body having flexibility so that it can be inserted into the inner peripheral part 5a by bending to some extent in the radial direction like a snap ring. It is.

The assembly using the maintaining means I according to the second separate structure is as follows. That is, the split ring 35 is placed in advance in the inner peripheral portion 5a by the above-described procedure, and the subsequent steps are the same as in the case of the maintaining means I having the first separate structure. Therefore, further explanation of the assembly procedure is omitted.

Example 4
FIG. 8 shows a connection structure between flange pipes according to the fourth embodiment. This is different from the first embodiment only in the maintaining means I, and the third different structure maintaining means I will be described. The third different structure maintaining means I is the first in the state along the axis P direction of the first and second flange portions 1B and 2B.
, 2 are formed of through holes 1h, 2h formed in the outer diameter side portions of the flange portions 1B, 2B, and bolts 41 and nuts 42 that can pass through these pipe through holes 1h, 2h.

The bolts 41 and nuts 42 constituting the third separate structure maintaining means I are connected to the flange portions 1.
B and 2B are provided at a plurality of locations around the B (eg, 3 locations) at equal angles, and the first and second flange portions 1B and 2B can be pulled toward each other, and the pulling is possible. The state can be maintained. That is, by tightening the bolt 41 and the nut 42, the first and second flange portions 1B and 2B are moved closer to each other via the gasket G, and both flange portions 1B are moved.
, 2B and the annular grooves 51 on both end faces of the gasket G are press-fitted to maintain the joined state in which the fitting seal portion 3 is formed.

Example 5
The connection structure between the flange pipes according to the fifth embodiment is the same as that of the first embodiment except that the fitting seal portion 3 is different, and differences will be described. This is a connection structure in which the taper angle of the portion where the gasket G and the flange pipe 1 or 2 are fitted is set to an angle close to a right angle.

That is, as shown in FIGS. 9 and 10, the fitting seal portion 3 has an opening angle (opening angle of the valley portions 14 and 15) D of the tapered circumferential surfaces 12 a and 13 a on the annular protrusion side of the annular pressing protrusions 12 and 13. Is 50
It is set to a value in the range of ˜70 degrees (50 ° ≦ D ° ≦ 70 °), and the sharp angle E of the tapered peripheral surfaces 52a, 53a of the peripheral wall end portions 52, 53 is a value in the range of 60 to 80 degrees ( 60 ° ≦ D ° ≦ 80 °
) Is set. The opening angle D and the sharpness angle E are set so that the opening angle D plus 10 to 20 degrees becomes the sharpening angle E [D ° + (10 to 20 °) = E °]. Yes. More preferable values are an opening angle D of 69 to 71 degrees (D ° = 70 ± 1 °) and a sharpness angle E of 79.
˜81 degrees (E ° = 80 ± 1 °), and the sharp angle E 2 is an opening angle D + 9 to 11 degrees (E ° −D °)
= 10 ± 1 °).

Further, the cut angle Ds of the inclined cut surfaces 12b and 13b of the annular presser protrusions 12 and 13 is 49 to 49.
It is set to 51 degrees (Ds ° = 50 ° ± 1 °), and the angle of attack Es of the front end cut surfaces 52b, 53b of the peripheral wall end portions 52, 53 is 124 to 126 degrees (Es ° = 125 ° ± 1 °). Is set to With such an angle setting, the taper outer peripheral surface 12a and the taper inner peripheral surface 52a, and the taper inner peripheral surface 13a and the taper outer peripheral surface 53a come into contact with each other in an annular line contact state. It will be exhibited in the next seal portion S2.

That is, the taper peripheral surface 52a formed in the peripheral wall end portions 52 and 53 with respect to the drawing direction, which is the direction in which the first fluid supply / discharge port portion 1A and the second fluid supply / discharge port portion 2A are drawn together.
, 53a (tapered inner circumferential surface 52a, tapered outer circumferential surface 53a) has a sharp angle E of the tapered circumferential surface 12 on the annular projection 11 side in the annular pressing projections (support portions) 12 and 13 with respect to the pulling direction.
The opening angle D of a and 13a (tapered outer peripheral surface 12a, tapered inner peripheral surface 13a) is set to a value obtained by adding 10 to 20 degrees, preferably 10 degrees or almost 10 degrees. The sharp angle E is 60.
It is set to -80 degrees, preferably 80 degrees or almost 80 degrees.

In this way, if the sharp angle E and the opening angle D are set to an obtuse value close to 90 degrees,
The annular presser protrusions 12 and 13 have a smaller amount of protrusion in the pulling direction (axial direction) than their radial widths, so that the strength and rigidity are relatively improved, and the peripheral wall end portions 52 and 53 are expanded. While regulating, there is an advantage that it is possible to more effectively suppress the possibility that itself (the annular presser protrusions 12 and 13) expands in the radial direction and is deformed. And trough parts 14 and 15 of peripheral wall edge parts 52 and 53
Since the taper peripheral surfaces 52a and 53a push the annular presser protrusions 12 and 13 in the radial direction by piercing into the ring, it is possible to reduce the component force, and also from this point, the deformation of the annular presser protrusions 12 and 13 in the radial direction is suppressed. be able to.

In the fifth embodiment, a relationship d1> d2 is set between the width d1 of the first annular protrusion 11 and the width d2 of the left annular groove 51, and preferably d1 × (0.6 to 0). .8) = d 2, but between the included angle α ° of the entire inner and outer valleys 14 and 15 and the sharp angle β ° of the entire inner and outer annular seal protrusions 52 and 53, α ° <β The relationship of ° is set, and it is preferable to set the relationship of α ° + (20-40 °) = β °.

[Other Examples]
Gasket G can be of synthetic resin having flexibility. As the maintaining means I with a pulling function, a turnbuckle type is also possible. Of the annular presser protrusions 12, 13, 22, and 23, the annular retainer protrusions 13 and 23 are replaced with the annular retainer wall portions 13 and 23, and the annular retainer protrusions 12 and 22 and the annular retainer wall portion. 13 and 23 are collectively defined as “annular presser portions”.

Overall schematic diagram showing the connection structure between flange pipes (Example 1) FIG. 1 is a cross-sectional view of the main part showing the connection structure of FIG. (A)-(c) is explanatory drawing which shows the connection procedure of the connection structure of FIG. Sectional drawing which shows the principal part in the decomposition | disassembly state of FIG. Enlarged sectional view of the main part showing details of the fitting structure between the gasket and flange piping Sectional drawing of the principal part which shows the 1st another structure of the maintenance means with a drawing function (Example 2) Sectional drawing of the principal part which shows the 2nd another structure of the maintenance means with a drawing function (Example 3) Sectional drawing of the principal part which shows the 3rd another structure of the maintenance means with a drawing function (Example 4) Side view showing state before assembly of gasket and flange piping (Example 5) The expanded sectional view of the principal part which shows the detail of the connection structure shown in FIG.

DESCRIPTION OF SYMBOLS 1 1st flange piping 1A Tubular part 1B 1st flange part 1n Male thread part 1h Through-hole 2 2nd flange piping 2A Tubular part 2B 2nd flange part 2h Through-hole 2k Outer peripheral surface 3 Mating seal part 4 Fluid passage 5 Cylindrical shape Nut 5m Inner peripheral surface portion 5n Female thread portion 6 Inward flange 6a Opening portion 11, 21 Annular projection 12, 13, 22, 23 Annular pressing portion 12a, 13a, 22a, 23a Taper peripheral surface 14, 15, 24, 25 Valley portion 32 cylindrical bolt 32m inner peripheral surface portion 32n male screw portion 33 cylindrical nut 33m inner peripheral surface portion 33n female screw portion 34 inward flange 34a opening 35 first split ring, second split ring 41 bolt 42 nut portion 51 annular Groove 52, 53 Peripheral wall end 52a, 53a Tapered peripheral surface G Gasket I Maintaining means P Shaft center S2 Seal portion W Fluid path X Center line along the interlinking center line Z axis

Claims (9)

The first flange portion of the first flange pipe having a first flange portion having a diameter larger than that of the tubular portion and made of a synthetic resin at the end of the tubular portion having the tubular fluid passage, and the tubular fluid passage. The second flange portion of the second flange pipe having a second flange portion having a diameter larger than that of the tubular portion and made of synthetic resin at an end portion of the tubular portion, and the first flange portion and the second flange portion, It is a connection structure of flange pipes that communicate with each other via a ring-shaped gasket interposed between them.
In the first flange portion and the second flange portion, an annular protrusion is formed on an outer diameter side portion of each fluid passage that opens to face each other and faces each other,
The gasket includes a fluid path formed to communicate the fluid passages corresponding to each other of the first and second flange portions, and an annular protrusion formed on each end surface of the first and second flange portions. It is made of a flexible material having a pair of annular grooves formed on the outer diameter side portion of the fluid path to be fitted to each other,
The first flange portion and the second flange portion are attracted to each other via the gasket, the annular protrusion of the first flange portion, the annular groove at one end of the gasket, and the second flange portion. The annular protrusion and the annular groove at the other end of the gasket are fitted to each other, and maintenance means for maintaining a joined state in which a fitting seal portion is formed is provided .
The gas is provided on the inner and outer diameter sides of the annular projections on the end surfaces of the first and second flange portions.
Inner and outer peripheral wall end portions protruding in the axial direction to form the annular groove in the ket
Annulus that suppresses or prevents deformation due to the engagement between the annular groove and the annular protrusion.
The presser part is formed,
In the joined state, the peripheral wall end portion and the annular pressing portion are pressed to form a seal portion.
Configured to
The annular presser portion is so formed that the valley surrounded by this and the annular protrusion is constricted.
The side peripheral surface on the annular projection side is formed in a tapered portion having an inclined tapered peripheral surface.
The peripheral wall end has a tapered peripheral surface that abuts the tapered peripheral surface of the annular pressing portion.
It is formed in a tapered annular protrusion that can enter the valley, and in the joined state,
The peripheral wall end part enters the valley part, and the both tapered peripheral surfaces are pressed against each other.
Connection structure of the flange pipe to each other you are. A cross-sectional shape of the gasket is a center line along the axial direction of the first and second flange portions;
And connection structure of the flange pipe each other according to claim 1, which consists in those having a substantially H shape which is line symmetrical with respect to both the center line perpendicular to the center line. It said maintaining means, according to the said first flange portion and the second flange portion to claim 1 or claim 2 is configured as to exert pull shifting function for obtaining the bonding state by attracting Connection structure between flange pipes. The maintaining means has an outer diameter larger than that of the first flange portion, and is externally fitted to the tubular portion of the first flange pipe so as to interfere with the first flange portion in the axial direction of the first and second flange pipes. A first split ring,
An inward flange having an opening that allows passage of the first flange portion and interferes with the first split ring in the axial direction is formed at one end portion, and on the outer periphery of the other end portion. A cylindrical bolt in which a male screw part is formed;
A second split ring that has an outer diameter larger than that of the second flange portion and is fitted onto the tubular portion of the second flange pipe so as to interfere with the second flange portion in the axial direction;
An inward flange having an opening that allows passage of the second flange portion and interfering with the second split ring in the axial direction is formed at one end portion, and an inner periphery of the other end portion And a cylindrical nut formed with a female screw portion that can be screwed into the male screw portion.
By the tightening operation of the cylindrical bolt and the cylindrical nut by screwing the male screw portion and the female screw portion, the first flange portion and the second flange portion are pulled together via the gasket. The connection structure between flange pipes according to claim 3 , which is configured so as to be brought close to each other. The maintaining means includes a cylindrical nut having a female screw portion that can be screwed into a male screw portion formed on an outer peripheral portion of one of the first flange portion and the second flange portion, and the first nut. An outer side of the tubular portion of either the first flange portion or the second flange portion so as to interfere with the other of the flange portion and the second flange portion in the axial direction of the first and second flange portions. Consisting of a split ring to be fitted,
One end of the cylindrical nut has an opening that allows passage of the other of the first flange portion and the second flange portion and interferes with the split ring in the axial direction. An inward flange is formed,
The flange piping according to claim 3 , wherein the first flange portion and the second flange portion are pulled together via the gasket by a tightening operation of the cylindrical nut to the male screw portion. Connection structure between each other. The maintaining means includes a through hole formed in one of the first flange portion and the second flange portion, and the other one of the first flange portion and the second flange portion through the through hole. And a bolt that is screwed onto the provided nut portion,
4. The flange pipe according to claim 3 , wherein the first flange portion and the second flange portion are attracted to each other via the gasket by screwing and tightening the bolt to the nut portion. Connection structure between each other. The connection structure between flange pipes according to claim 4 or 5 , comprising at least one of the following (A) and (B).
(A) An inner peripheral surface portion of a split ring inner fitting portion adjacent to the inward flange of the cylindrical bolt or / and the cylindrical nut is formed on a flat inner peripheral surface concentric with the tubular fluid passage. ,
And the internal diameter of the internal peripheral surface part and the outer diameter of the said split type ring formed in the cross-sectional rectangle are formed in the substantially same diameter.
(B) The outer diameter portion of the tubular portion on which the split ring is fitted is formed on a flat outer peripheral surface concentrically with the tubular fluid passage, and the outer diameter of the outer peripheral surface and the split mold The inner diameter of the ring is substantially the same. Connecting structure of the flange pipe each other according to any one of claim 1 to 7, wherein the gasket is formed by a fluororesin. The connection structure of flange piping as described in any one of Claims 1-8 in which the said 1st and 2nd flange part is formed with the fluororesin.

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