JP2003014172A - Pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To seal pipe ends of both pipes, and to secure the shape of a gasket, and to prevent a put-out of the pipe. SOLUTION: This pipe joint is provided with a cylindrical gasket having an inner diameter a little larger than the outer diameter of the pipe ends of both the pipes and having a relatively thin thickness, and a fastening housing for surrounding the peripheral surface of the gasket. The inner diameter of annular projections provided in the inner peripheral surface of the gasket is formed a little smaller than the outer diameter of the pipe.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint in which the pipe ends of both pipes are sealed with a cylindrical gasket and the tightening housing keeps the gasket in shape and prevents the pipe from coming off.

[0002]

2. Description of the Related Art In pipe construction, a victoric pipe joint is a movable joint that can be easily applied to stainless steel pipes, carbon steel pipes, iron pipes, etc., and can absorb bending and expansion and contraction of pipes. In general, a victorique type pipe joint is constructed by fitting an annular gasket to both pipe ends of a pipe to be connected, covering a short tubular housing from above, and tightening the gasket with bolts and nuts so that the pipe ends Press and seal.

In the case of a victorique type pipe joint, it is necessary to lock both circumferential side edges of a short-cylinder-shaped tightening housing to both pipe ends, and for this purpose, metal rings are welded to both pipe ends, respectively. However, since welding of metal rings is a very complicated work, it is currently the mainstream to form an annular groove by grooving the pipe end. At the time of assembly, the inwardly bulging portions at both ends of the tightening housing are fitted into the annular groove at the end of the pipe to prevent the pipe joint from coming off.

[0004]

In this type of pipe joint, the inner diameter of the gasket is smaller than the outer diameter of the pipe, and it is very troublesome to expand the inner diameter of the rubber gasket and attach it to the pipe end portion of the pipe. is there. In addition, the gasket is tightened in the housing to compress and deform it, and the gasket is crimped to the pipe end.If the bolts and nuts are not tightened sufficiently, water will leak from the joint, and if tightened too much, the gasket will be damaged. Will be done.

As an existing pipe joint, Japanese Patent Publication No. 55-25
As disclosed in Japanese Patent No. 316, there is a pipe joint in which a gasket and a housing are integrated and which can be constructed by simply inserting a pipe. In this pipe joint, the claws of the retaining member are bitten into the outer peripheral surface of the pipe, and therefore, there is a defect that if the outer peripheral surface of the pipe is poorly finished, it will easily come off, and even if the tightening is loose, it will come off. On the other hand, Japanese Patent Laid-Open No. 7-119870 discloses
While it is equipped with a pipe expulsion prevention mechanism to prevent forgetting work during construction, it requires tightening the two compression bands in addition to tightening the gasket, which increases the required work and the joint structure. It is complicated and expensive.

The present invention has been proposed in order to improve the above-mentioned problems associated with conventional pipe joints, and it is easy to attach the pipe to the pipe end and the housing may have a small tightening force. It is intended to provide a pipe joint. Another object of the present invention is to provide a pipe joint which has a simple overall structure and is inexpensive, and which does not have a wrong mounting position.

[0007]

In order to achieve the above object, a pipe joint according to the present invention comprises a relatively thin-walled cylindrical gasket having an inner diameter slightly larger than the outer diameters of the pipe ends of both pipes. And a tightening housing that surrounds and flexes the outer peripheral surface of the gasket, and the inner diameter of the annular protrusion provided on the inner peripheral surface of the gasket is slightly smaller than the outer diameter of the pipe. In this gasket, it is preferable that at least two rows of annular projections are provided on the inner peripheral surface of the gasket, and the longitudinal projections of the annular projections have a substantially right triangle shape.

With the pipe joint of the present invention, pipes each having two rows of annular grooves at the pipe end are connected. in this case,
The inner bulging portions at both ends of the gasket are fitted into the annular grooves on both pipe ends, and the inner bulging portions at both ends of the housing are fitted into the inner annular grooves of both pipes.

With the pipe joint of the present invention, pipes each provided with a row of annular grooves at the pipe ends may be connected. In this case, the inwardly bulged portions at both ends of the gasket and the housing are fitted into the annular grooves of both pipes, respectively.

Further, the pipe joint of the present invention may be used to connect pipes each provided with two or three or more rows of annular projections at their ends. In this case, the inward bulging portions at both ends of the gasket are located between the inner wall of the annular protrusion on the pipe end side of both pipes or between the annular protrusions, and the inwardly bulging portions at both ends of the housing are inwardly of both pipes. It is located between the side annular protrusions.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION When the pipe joint 1 according to the present invention is used, as shown in FIG. 1, the pipes 7, 7 to be connected are provided with annular grooves 3, 5, respectively. The number of this annular groove is shown in FIG.
As shown in FIG. 3, two columns are generally used, but one column may be used as shown in FIG. Instead of this annular groove, an annular protrusion 4 as shown in FIG.
8, 50 may be provided, and the number of the annular protrusions is two rows or three rows or more. In FIG. 1, the gasket 8 and the housing 10 are slightly deformed, the difference between the inner diameter of the gasket 8 and the outer diameter of the pipe 7 is smaller, and the thickness of the housing 10 is thinner.

The cylindrical gasket 8 is made of a relatively thin rubber or soft plastic and therefore is easily deformed, and has an inner diameter slightly larger than the outer diameter of the pipe end portion of the pipe 7.
The gasket 8 is provided with annular projections 12 and 14 on its inner peripheral surface, and at least two rows of annular projections abut on each pipe 7. That is, since at least two rows are provided from the center of the gasket 8 in the longitudinal direction, a total of at least four rows of annular protrusions are provided at predetermined intervals, and the annular protrusions have six rows or eight.
It is also possible to provide rows. If there is only one row for each of these annular protrusions, the prevention of water leakage will tend to be incomplete.

In the gasket 8, each annular protrusion 1
It is preferable that the vertical cross sections of 2 and 14 are substantially right-angled triangles. When the side wall surface 16 (FIG. 2) on the pipe insertion side is inclined and the side wall surface 18 on the opposite side is vertically set, the pipe 7 can be easily inserted. Besides, it is easy to prevent water leakage. The vertical cross section of the annular protrusion can be V-shaped, U-shaped, or semicircular. The minimum inner diameters of the annular protrusions 12 and 14 are set to be slightly smaller than the outer diameter of the fitting pipe 7 so that the annular protrusions can be in close contact with the outer peripheral surface of the pipe 7 over the entire circumference and need not be greatly deformed.

The inner diameter of both ends of the gasket 8 is narrowed by forming the inward bulging portions 20, 20 at both ends thereof. The inner diameter of each inward bulged portion 20 substantially matches the outer diameter of the annular groove 3, and the gasket 8 can be accurately positioned by fitting both bulged portions into the annular groove 3. Inward bulge 2
When 0 and 20 are fitted in the annular groove 3 of the pipes 7 and 7, the front end face 22 of the pipes 7 and 7 has a gap of 4 to 10 mm, and thus the bending and expansion and contraction of each pipe 7 can be absorbed.

The tightening housing 10 is formed of, for example, a curved plate that is close to a circular side surface that surrounds and flexes the outer peripheral surface of the gasket 8. The rods 24 are attached to both ends of the plate in the circumferential direction, and the parallel rods 24, 24 are provided.
This is a structure in which the tightening bolt 26 is screwed between the screw holes. As shown in FIG. 6, this housing may be composed of substantially half-cylindrical halves 70, 70 that fit into the annular grooves 3 of the pipes 7, 7.

The housing 10 has inner bulging portions 28, 28 formed at both ends thereof, so that the inner diameters of the both ends are narrowed. In the tightened state of the housing 10, the inner diameter of the bulging portion 28 substantially matches the outer diameter of the annular groove 5,
By fitting both bulged portions into the annular groove 5, the housing 10 can be accurately positioned and the pipes 7, 7 are prevented from coming off the pipe joint 1.

[0017]

EXAMPLES Next, the present invention will be explained based on examples, but the present invention is not limited to the examples. FIG. 1 shows a cross section of a pipe joint 1 according to the present invention, through which a pipe 7 having annular grooves 3 and 5 provided at pipe ends,
Connect 7. The annular grooves 3 and 5 have a predetermined interval, the annular groove 3 on the pipe end side is for a gasket, and the annular groove 5 on the inner side of the pipe is for a housing. The pipe 7 is, for example, a stainless steel pipe, and grooving of the two rows of the pipe may be performed in a pipe processing factory.

The pipe joint 1 includes a cylindrical gasket 8 having an inner diameter slightly larger than the outer diameter of the pipe end of the pipe 7.
Tightening housing 1 that surrounds the outer peripheral surface of the gasket
Has 0 and. The gasket 8 is made of synthetic rubber or natural rubber that is easily deformed because it is thin, and the housing 10 is
Generally, it is made of metal such as iron, stainless steel, copper and aluminum.

The cylindrical gasket 8 has an inner peripheral surface having a diameter slightly larger than the outer diameter of the pipe end of the pipe 7, and the inner peripheral surface has two rows of annular projections 12 for each fitting pipe 7. ，
14 contact, that is, a total of four rows of annular projections are provided at predetermined intervals. Each of the annular projections 12 and 14 has a vertical cross section of a substantially right-angled triangular shape, and the side wall surface 16 (FIG. 2) on the insertion side is inclined with respect to the fitting pipe 7, and the side wall surface 1 on the extraction side 1 is formed.
Set 8 vertically. The inner diameters of the annular protrusions 12 and 14 corresponding to the vertices of the right triangle are set to be slightly smaller than the outer diameter of the fitting pipe 7 and further capable of closely contacting the outer peripheral surface of the pipe 7 over the entire circumference.

The inner diameter of both ends of the gasket 8 is narrowed by forming the inward bulging portions 20 and 20 at both ends thereof. The vertical cross section of the inward bulging portion 20 corresponds to that of the annular groove 3 on the pipe end side, and the inner diameter of the bulging portion is the annular groove 3
It almost matches the outer diameter of. Inner bulge 2 of gasket 8
When 0 and 20 are fitted into the annular groove 3 of the pipes 7 and 7, as shown in FIG.
As illustrated in, the front end faces 22 of the pipes 7, 7 have a predetermined gap, and the gap is usually around 5 mm.

The tightening housing 10 is composed of a curved plate that is close to a circular side surface that surrounds the outer peripheral surface of the gasket 8 and has rods 2 at both ends in the circumferential direction of the plate.
4 (one of the two shown) is attached and the parallel rod 2
The fastening bolt 26 is screwed into the screw holes of 4, 24. The tightening bolt 26 is defined according to the lateral width of the housing 10, and as shown in FIG.
It may be two as shown in FIG. 1 or one as shown in FIG.

The housing 10 has, for example, a shallow U-shaped vertical cross section, and the inner bulging portions 28, 28 are formed at both ends of the housing 10 so that the inner diameters of the both ends are narrowed.
The vertical cross section of the inward bulge 28 corresponds to that of the annular groove 5 on the pipe end side, and the inner diameter of the bulge 28 substantially matches the outer diameter of the annular groove 5 in the tightened state. The inner diameter of the inner peripheral surface of the housing is set to be substantially the same as or slightly smaller than the outer diameter of the outer peripheral surface of the gasket in the tightened state.

When the pipe joint 1 is attached, the gasket 8 is fitted to the one pipe 7, and the inward bulging portion 20 of the gasket is fitted into the annular groove 3 of the pipe. Next, the other pipe 7 is inserted from the other end of the gasket 8, and the annular groove 3 of the pipe is fitted to the other bulge 20 of the gasket 8. Since the outer diameter of the pipes 7 and 7 is larger than the inner diameter of the gasket, the pipes 7 and 7 can be easily inserted by slightly deforming the annular protrusions 12 and 14, and the bulged portions 20 and 20 of the gasket 8 can be inserted into the annular grooves of the pipes 7 and 7. Since it is fitted in the No. 3, the gasket can be easily positioned. FIG. 1 shows a state in which the pipes 7, 7 are completely inserted, and in this state, the front end face 2 of the pipes 7, 7 is
2 has a gap, and the gasket 8 is in close contact with the outer peripheral surface of the pipe 7 via the annular projections 12 and 14.

The tightening housing 10 is attached to the gasket 8 in advance, or the gasket 8 is fitted to the pipes 7 and 7 and then attached. When the bolts 26, 26 are tightened, the inner peripheral surface of the housing 10 comes into close contact with the outer peripheral surface of the gasket 8 and the shape of the gasket is reliably retained. In the pipe joint 1, since the amount of tightening the gasket 8 in the housing 10 is small and the tightening by the bolts 26, 26 is completed immediately, water leakage may occur in the joint or the gasket 8
Will not be damaged.

FIG. 3 shows a modified example of the pipe joint 3
The pipes 32, 32 each having a row of annular grooves 34 at the ends of the pipes are connected to each other via 0. The annular groove 34 serves both as a gasket and as a housing.

The pipe joint 30 is a cylindrical gasket 3 having an inner diameter slightly larger than the outer diameter of the pipe end of the pipe 32.
6 and a tightening housing 38 that surrounds and flexes the outer peripheral surface of the gasket. In the gasket 36, the inner diameters of the inner bulging portions 40 at both ends thereof substantially match the outer diameter of the annular groove 34, and the lateral width of the longitudinal section thereof is approximately half the lateral width of the annular groove 34. On the other hand, in the housing 38, in the tightened state, the inner diameters of the inward bulging portions 42 at both ends thereof are equal to the annular groove 3.
4 is almost the same as the outer diameter of the circular groove 34.
Is about half the width of.

The inner diameter of the inner peripheral surface of the housing 38 is set to be substantially the same as or slightly smaller than the outer diameter of the outer peripheral surface of the gasket in the tightened state. Further, the vertical inner dimension of the housing 38 is determined so as to substantially match the vertical outer dimension of the gasket 36. The housing 38 is preliminarily fitted to the gasket 36 or the gasket 36 is attached to the pipe 3.
When the bolts 44 are tightened by fitting after fitting with Nos. 2 and 32, the entire inner peripheral surface of the housing 38 comes into close contact with the outer peripheral surface of the gasket 36, so that the shape of the gasket is surely maintained.

FIG. 4 shows another modified example of the pipe joint, in which annular groove protrusions 48 and 5 are respectively provided at the pipe end portions through the pipe joint 46.
The pipes 52 and 52 provided with 0 are connected. Annular protrusion 4
8 and 50 are the positioning of the gasket 53 and the housing 54.
Used to lock the.

The pipe joint 46 is a cylindrical gasket 5 having an inner diameter slightly larger than the outer diameter of the pipe end of the pipe 52.
3 and a tightening housing 54 that surrounds and flexes the outer peripheral surface of the gasket. In the gasket 53, the inner diameters of the inner bulging portions 56 at both ends thereof substantially match the outer diameter of the pipe 52. On the other hand, in the housing 54, in the tightened state, the inner diameters of the inward bulging portions 58 at both ends thereof are equal to the pipe 5
2 is approximately the same as the outer diameter, and the lateral width of its longitudinal section is the annular protrusion 4.
The inner dimension between 8 and 50 is made almost equal.

The inner diameter of the inner peripheral surface of the housing 54 is determined to be substantially the same as or slightly smaller than the outer diameter of the gasket outer peripheral surface in the tightened state. Housing 54
Is fitted to the gasket 53 in advance, or fitted after fitting the gasket 53 to the pipes 52, 52,
When the bolts 60, 60 are tightened, the entire inner peripheral surface of the housing 54 comes into close contact with the outer peripheral surface of the gasket 53, and the shape of the gasket is reliably retained.

The gasket 62 shown in FIG. 5 may be made of a soft plastic having a relatively small stretchability, and the inner peripheral surface of the gasket 62 has two rows of annular protrusions 64, 66 with respect to the fitting pipe.
That is, a total of four rows of annular protrusions are provided at predetermined intervals. On both circumferential surfaces of both ends of the gasket 62, 3 to 12 slits 68 are formed in the axial direction at equal intervals in the circumferential direction.
8 extends to the vicinity of the annular protrusion 64, the annular protrusion 6
The length does not reach 4.

The gasket 62 can be easily inserted by fitting the pipe 7 as shown in FIG. 1 by expanding the inward bulging portion 70 slightly outward, and the inner bulging portion 70 can be easily inserted.
It becomes easy to push in and fix to the annular groove 3.
By using the gasket 62, it is possible to interpose the inward bulging portion 70 between the two rows of annular protrusions as shown in FIG. Since the gasket 62 is clamped to the outer peripheral surface of the gasket 62 by pressure, the gasket 62 does not come off or water leaks from the slit even if the slit 68 is formed.

The tightening housing used in the present invention is
As shown in FIG. 6, it may be composed of substantially half-cylindrical halves 70, 70 fitted in the annular groove 3 of the pipes 7, 7. Each half body 70 is provided with a recess 72 having a semicircular side surface at the center, and the gasket 8 is fitted into the recess. In each half body 70, two sets of bolts which extend linearly on the outer peripheral surface outward in the diametrical direction and pass through the through holes of the opposite extension parts of both half bodies. It is integrated by the nut 76.

To install this housing, as shown in FIG. 7, a bolt-nut 76 is attached to one of the extension parts 74 and 74 of the half halves 70, 70 to surround the gasket 8 fitted to both pipes 7. To arrange. Half body 7
0 and 70 are brought close to each other as shown by the alternate long and short dash line in FIG. 7, and the bolts and nuts 76 are also attached to the other extensions 74 and 74. Two
When the bolt-nut 76 of the set is tightened, the half body 70,
Gasket 8 is pressure-bonded between the annular grooves of both pipes 7 by 70 to maintain airtightness.

[0035]

EFFECTS OF THE INVENTION The pipe joint according to the present invention is accurate and easy to mount on the pipe end portion of the pipe, and requires only a small tightening force for the housing, resulting in good workability and workability. In this pipe joint, both ends of the gasket and the housing can be easily fitted into the annular groove or the annular protrusion of the pipe, and it is also easy to confirm that they are completely fitted.

Further, in the pipe joint of the present invention, the structure of the cylindrical gasket is simple and can be manufactured at low cost as a whole. This gasket can be easily fitted to the pipes by only slightly deforming the annular projection on the inner peripheral surface of the gaskets. Can be absorbed. This gasket adheres sufficiently to the outer peripheral surface of the pipe through the easily deformable annular protrusion,
Water leakage can be almost completely prevented.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing a pipe joint according to the present invention.

FIG. 2 is a cross-sectional view showing a cylindrical gasket used in a pipe joint with a part thereof cut away.

FIG. 3 is a schematic sectional view showing a modified example of the present invention.

FIG. 4 is a schematic sectional view showing another modification of the present invention.

FIG. 5 is a partially cutaway sectional view showing a modified example of a cylindrical gasket.

FIG. 6 is a side view of a pipe joint showing another example of the tightening housing.

FIG. 7 is a side view showing a mounting mode of the housing.

[Explanation of symbols]

1 Pipe fitting 3,5 annular groove 7,7 pipe 8 gasket 10 Tightening housing 12,14 Annular protrusion 20, 20 Gasket inward bulge

Claims (4)

[Claims] 1. A pipe joint for connecting pipes each having two rows of annular grooves at pipe ends, and having a relatively thin cylindrical shape having an inner diameter slightly larger than the outer diameters of the pipe ends of both pipes. Of the gasket, and a tightening housing that surrounds and flexes the outer peripheral surface of the gasket, the inner diameter of the annular projection provided on the inner peripheral surface of the gasket is slightly smaller than the outer diameter of the pipe,
A pipe joint in which inner bulging portions at both ends of the gasket are fitted into annular grooves on both pipe ends, and inner bulging portions at both ends of the housing are fitted into annular grooves on both pipe inner sides. 2. A pipe joint for connecting pipes each provided with a row of annular grooves at the pipe ends, and having a relatively thin cylindrical shape having an inner diameter slightly larger than the outer diameters of the pipe ends of both pipes. Of the gasket, and a tightening housing that surrounds and flexes the outer peripheral surface of the gasket, the inner diameter of the annular projection provided on the inner peripheral surface of the gasket is slightly smaller than the outer diameter of the pipe,
A pipe joint in which the inwardly bulged portions at both ends of the gasket and the housing are respectively fitted in the annular grooves of both pipes. 3. A pipe joint for connecting pipes each having two or three or more rows of annular projections at the pipe ends, the pipe joints having an inner diameter slightly larger than the outer diameters of the pipe ends of both pipes. A thin cylindrical gasket and a tightening housing that flexes around the outer peripheral surface of the gasket. The inner diameter of the annular protrusion provided on the inner peripheral surface of the gasket is slightly smaller than the outer diameter of the pipe. The inward bulging portion of the pipe portion is located between the inner sidewalls or the annular protrusions of the annular projections on both pipe end sides, and the inwardly bulging portions of both ends of the housing are located between the inner pipe annular protrusions of both pipes. Pipe fittings. 4. The ring-shaped projection on the inner peripheral surface of the gasket is brought into contact with each pipe in at least two rows or more, and the vertical section of the ring-shaped projection is substantially a right triangle. Pipe fittings.