JP2003254476A - Mechanical pipe joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To certainly join not less than two kinds of connecting pipes having different diameters by a single structure without exchanging parts. <P>SOLUTION: In this mechanical joint, a slipping-off preventive member 5 preventing slipping off of an end portion 6a of a connecting pipe 6 by fastening a cap nut 2 to a joint main body 1 comprises: a cutting edge 5f inwardly projecting in a diametrical side neat an inner end surface 5h; a cylindrical inner surface 5d inwardly projecting in the diametrical direction neat an outer end surface 5g and abutting on an outer peripheral surface of the connecting pipe 6; and a notch portion 5e provided between the cylindrical inner surface 5d and the cutting edge 5f. When a pair of the connecting pipes 6 having large diameters, the cap nut 2 abuts on an outside position 5b in an axial direction of the outer peripheral surface 5a of the slipping-off preventive member 5, and the outer peripheral surface of the connecting pipe 6 is gripped by the cylindrical inner surface 5d of the slipping-off preventive member 5. When a pair of the connecting pipes 6 having small diameters, the cap nut 2 applies large diameter contracting force to the slipping-off preventive member 5 from the outer end surface 5g side to the inner end surface 5h side, thereby pressing the cutting edge 5f against the outer peripheral surface of the connecting pipe 6. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint, and more particularly to a mechanical pipe joint capable of joining connecting pipes having different diameters with a single structure.

[0002]

2. Description of the Related Art For example, utility model registration No. 2500549
As shown in the publication, a seal member arranged between a joint body and an end portion of a connecting pipe, a cap nut connected to a screw portion formed at the end portion of the joint body, and a bag for the joint body. A mechanical pipe joint having a retaining member that prevents the connecting pipe from coming out by tightening a nut is known. This mechanical pipe joint has excellent workability in which the connecting pipe can be directly joined by the pipe joint without screwing the end portion of the connecting pipe, and has structural flexibility and stretchability. For this reason, it is used for pipe joining of fluid supply pipes in various fields including water supply pipes for supplying water or hot water, and air-conditioning pipes for cooling water and cold / hot water.

For example, as shown in FIG. 9, a conventional retaining member (50) has an outer peripheral surface (50a), an inner peripheral surface (50b) which contacts an outer peripheral surface of a connecting pipe (not shown), and an axial direction. It is provided with an outer end surface (50c) arranged on the outer side and formed in the radial direction, and an inner end surface (50d) arranged on the inner side in the axial direction and formed in the radial direction. The outer peripheral surface (50a) is formed in a tapered shape and contacts the tapered surface of a cap nut (not shown), and the inner peripheral surface (50b)
A plurality of annular protrusions (50e) are provided at a predetermined distance in the axial direction. On the outer peripheral surface (50a) formed in a tapered shape,
Since the tapered surface of the cap nut abuts at various positions from the outer small diameter position to the inner large diameter position, the retaining member (50)
Can prevent the connecting pipes having different outer diameters from coming off.

[0004]

In the retainer member that comes into contact with the connecting pipe and prevents the connecting pipe from coming off, the blade shape and the material of the retainer member differ depending on the pipe type of the connecting pipe having different materials. A steel retaining member is used for a steel pipe, and a polyethylene or resin retaining member is often used for a polyethylene pipe. For example, in the field of water pipes, pipe materials such as steel pipes, vinyl chloride pipes, and polyethylene pipes are used, and there are many pipe types that have the same nominal diameter but different pipe outer diameters or tolerances. For example, when comparing the tolerance of the standard outer diameter according to JIS standard and the outer diameter of the pipe for the nominal 25 of galvanized steel pipe, polyethylene pipe for water supply, and hard vinyl chloride pipe for water supply, the outer diameter is 34
Since the steel pipe with a diameter of ± 0.5 mm is the largest and the vinyl chloride pipe with a diameter of 32 ± 0.2 mm is the smallest, the outer diameter difference between the maximum diameter and the minimum diameter is 3
4.5-31.8 = 2.7 mm. Conventional retaining member
In the case of (50), even if the retaining of a steel pipe having a large diameter can be achieved relatively favorably, the retaining of a resin pipe having a small diameter cannot be achieved.

It is an object of the present invention to provide a mechanical pipe joint which can surely join two or more kinds of connecting pipes having different diameters with a single structure without exchanging parts.

[0006]

[Means for Solving the Problems] A mechanical pipe joint according to the present invention comprises a joint body (1) forming a cavity (1a) into which a connection pipe (6) is inserted, a joint body (1) and a connection pipe (6). End of the joint body (1) and the sealing member (3) arranged between the end (6a) of
A cap nut (2) having a threaded portion (2b) connected to a threaded portion (1c) formed in (1b) and a tapered surface (2a), and a joint body.
It has a retaining member (5) for preventing the end portion (6a) of the connecting pipe (6) from coming out by tightening the cap nut (2) with respect to (1). The retaining member (5) is formed in a taper shape and has an outer peripheral surface (5a) that is in contact with the tapered surface (2a) of the cap nut (2) and an outer surface that is arranged radially outside and in the radial direction. End face (5
g), an inner end surface (5h) that is arranged on the inner side in the axial direction and is formed in the radial direction, and an abutment gap capable of reducing the diameter. The retaining member (5) has a blade (5f) protruding radially inward in the vicinity of the inner end surface (5h) and an outer peripheral surface of the connecting pipe (6) protruding radially inward in the vicinity of the outer end surface (5g). An inner surface (5d) of the cylinder, and a notch (5e) provided between the inner surface (5d) of the cylinder and the blade (5f).

When connecting a pair of connecting pipes (6) having a large outer diameter, the cap nut (2) comes into contact with the axially outer position (5b) of the outer peripheral surface (5a) of the retaining member (5). In addition, a large reducing force is applied to the retaining member (5) from the inner end surface (5h) side to the outer end surface (5g) side, and the cylindrical inner surface (5d) of the retaining member (5) is connected to the connecting pipe (6). Hold the outer peripheral surface. When connecting a pair of connecting pipes (6) with a small outer diameter, the cap nut (2) is the outer peripheral surface (5a) of the retaining member (5).
It comes into contact with the inner side position (5c) in the axial direction, and a large reducing force is applied to the inner end face (5h) side from the outer end face (5g) side to the retaining member (5) and the blade (5f) is connected. Press on the outer peripheral surface of (6). For this reason, steel pipes with a large diameter and resin pipes with a small diameter are connected.
In any case of joining as (6), the single retaining member (5) can be used to surely prevent retaining.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a mechanical pipe joint according to the present invention will be described below with reference to FIGS. Figure 1
As shown in Fig. 3, the mechanical pipe joint according to the present invention has a hollow body (1a) into which a pair of connecting pipes (6) are inserted, and a joint body (1) formed into a substantially cylindrical shape by cast iron, and a joint. Body
(1) and a sealing member (3) arranged between the end (6a) of each connecting pipe (6), and a threaded portion (1c) formed at both ends (1b) of the joint body (1). Cap nut (2) with thread (2b) connected to
A retaining member (5) that prevents the end portion (6a) of the connecting pipe (6) from coming off by tightening the cap nut (2) to the joint body (1), the retaining member (5) and the joint body (5). 1) and a washer (4) disposed between the end (1b) and the end (1b). Seal member
(3) is formed of a rubber material having elasticity and forming a watertight packing. The cap nut (2), the washer (4) and the retaining member (5) are made of a metal selected from iron, cast iron, stainless steel, brass and the like.

Although not shown, the retaining member (5) formed in the shape of a ring is provided with a notch portion serving as a gap in the circumference of the retaining member (5) so that the retaining member (5) can be reduced in diameter or expanded in diameter. Becomes The retaining member (5) is formed in a tapered shape, and an outer peripheral surface (5a) which is in contact with the tapered surface (2a) of the cap nut (2) and an outer surface which is arranged on the outer side in the axial direction and is formed in the radial direction. End face (5g)
And an inner end face (5h) formed in the axial direction and in contact with the washer (4) on the inner side in the axial direction, and formed radially inside the inner end face (5h) and protruding inward in the radial direction. A blade (5f) having a triangular cross section and a cylindrical inner surface (5) that is formed inside the retaining member (5) in parallel with the outer surface of the connecting pipe (6) and is in contact with the connecting pipe (6).
d) and the notch provided between the inner surface (5d) of the cylinder and the blade (5f)
(5e) and. The outer peripheral surface (5a) of the retaining member (5) is formed as a tapered surface that continuously changes from an axial outer position (5b) to an axial inner position (5c). Inner surface of cylinder (5
The length d) is about 1/3 to 2/3 of the total length of the retaining member 5 and is provided parallel to the outer surface of the connecting pipe 6. Notch (5e)
Is provided on the radially outer side from the inner end in the axial direction of the cylindrical inner surface (5d) parallel to the outer peripheral surface of the connecting pipe (6) to the inner end surface (5h), and at the inner end of the notch (5e). A blade (5f) is formed. Blade (5f)
Has a dimensional difference within 1 mm and projects radially inward from the inner surface (5d) of the cylinder, and the projection angle θ of the blade (5f) is within the range of 30 to 120 degrees. In the illustrated example, an example in which an annular single blade (5f) is provided is shown, but a plurality of blades (5f) are axially spaced to form an inner end surface (5h) of the retaining member (5). It may be formed on the inner peripheral surface. Further, the blade (5f) can be provided not only on the inner end of the retaining member (5) but also in the vicinity of the inner end.

Since the outer peripheral surface (5a) can be reduced or expanded in diameter depending on the clearance, the blade (5f) and the cylindrical inner surface (5d) are different in connecting pipe (6) when the diameter is reduced or expanded. ), The parallel cylindrical inner surface (5d) and the blade (5f) of the retaining member (5) that can contact the outer surface of the connecting pipe (6) have a function of preventing the connecting pipe (6) from coming out. is there. The outer diameter of steel pipe is larger than that of common vinyl chloride pipe of the same type.

In manufacturing the retaining member (5), as shown in FIG.
As shown in Fig. 6, a rolled metal strip (60) having a rectangular cross section or a wire rod (61) having a circular cross section is formed into a taper shape (wire drawing), and a cutout (6) is formed on the bottom surface of the metal strip (60).
After forming 2), the retaining member (5) is completed by cutting into a predetermined length and forming (coiling) in an annular shape. A gap (63) is provided in a part of the annular retaining member (5).

As shown in FIG. 3, a pair of steel pipes, which are steel pipes, are inserted into the hollow portion (1a) of the joint body (1) through the retaining member (5), the washer (4) and the sealing member (3) in a temporarily tightened state. Insert the connecting pipe (6) and tighten the cap nut (2) with an appropriate tightening torque to perform the final tightening. As shown in Fig. 3, the cap nut (2)
The tapered surface (2a) comes into contact with the axially outer position (5b) provided on the outer peripheral surface (5a) of the retaining member (5). At this time, the retaining member (5) is reduced in diameter by tightening the cap nut (2), and the cylindrical inner surface (5d) of the retaining member (5) firmly clamps the outer peripheral surface of the connecting pipe (6), Since the blade (5f) bites into the outer peripheral surface of the connecting pipe (6), the pair of connecting pipes (6) can be connected by a pipe joint and a pulling-out preventing force of the connecting pipe (6) can be obtained.

On the other hand, when a resin pipe such as a vinyl chloride pipe is used as the connecting pipe (6), since the outer diameter of the resin pipe is smaller than the outer diameter of the steel pipe and has elasticity or flexibility, At the time of connection by a pipe joint, the retaining member (5) must be sufficiently reduced in diameter on the connecting pipe (6), and the blade (5f) must bite into the outer peripheral surface of the connecting pipe (6). Therefore, in the resin pipe,
Since it is necessary for the blade (5f) to bite into the connecting pipe (6) more than the clamping force by the cylindrical inner surface (5d) of the retaining member (5),
It is necessary to form the tip of the blade (5f) to be somewhat sharp. When using a resin pipe as the connection pipe (6), use a steel pipe in the cavity (1a) of the joint body (1) through the retaining member (5), washer (4) and seal member (3) in the temporarily tightened state. A pair of connecting pipes
Insert (6) and tighten the cap nut (2) with proper tightening torque to perform final tightening.
The taper surface (2a) of (2) comes in contact with the axially inner position (5c) provided on the outer peripheral surface (5a) of the retaining member (5). At this time, the retaining member (5) is further reduced in diameter by tightening the cap nut (2), and the cylindrical inner surface (5d) of the retaining member (5) is connected to the connecting pipe.
Firmly clamp the outer peripheral surface of (6), and the blade (5f) is a connecting pipe.
Since the diameter of the outer peripheral surface of (6) is reduced and bites into it, a pair of connecting pipes (6) can be connected with a pipe joint and
The pullout prevention force of (6) can be obtained. In this case, since the tapered surface (2a) of the cap nut (2) comes into contact with the axially inner position (5c) provided on the outer peripheral surface (5a) of the retaining member (5),
The reducing force of the cap nut (2) prevents the inner end surface (5
h) side, and the diameter reducing force acts on the blade (5f) side from the inner surface (5d) of the cylinder, and at the same time, the notch (5e) is formed, so that the blade (6 You can go deep into 5f).

Thus, a pair of connecting pipes having a large outer diameter
When connecting (6), the cap nut (2) should be attached to the retaining member (5).
It comes into contact with the axially outer position (5b) provided on the outer peripheral surface (5a), and applies a large reducing force to the retaining member (5) from the inner end surface (5h) side to the outer end surface (5g) side. The inner surface of the cylinder of the retaining member (5).
The outer peripheral surface of the connecting pipe (6) is gripped by (5d). When connecting a pair of connecting pipes (6) with a small outer diameter, the cap nut (2) contacts the inner position (5c) in the axial direction provided on the outer peripheral surface (5a) of the retaining member (5). In contact with each other, a large reducing force is applied to the inner end face (5h) side from the outer end face (5g) side to the retaining member (5), and the blade (5f) is pressed against the outer peripheral face of the connecting pipe (6). Therefore, in any case where a large-diameter steel pipe and a small-diameter resin pipe are joined as the connecting pipe (6), the single retaining member (5) can be used to reliably prevent the retaining. .

The embodiment of the present invention can be variously modified. For example, as shown in FIG. 6, a metal strip (60)
When the notch (62) is formed in the blade, if the axial V groove (64) is formed in the blade (5f) and the inner surface (5d) of the cylinder, the blade (5f) becomes sharp and the retaining action is further strengthened. You can Further, as shown in FIG. 7, the outer end surface (5g) or the inner end surface (5h) is formed into a curved protrusion to give rigidity to the blade (5f), and as shown in FIG.
(5h) may be formed in a curved concave surface to give elasticity to the blade (5f).

In the embodiment of the present invention, the following operational effects can be obtained. [1] The diameter of the retaining member (5) can be reduced in a wide range, so that connecting pipes (6) having different outer diameters can be connected with a sufficient retaining force even with a single structure. [2] Connection pipes (6) having different outer diameters can be connected without replacing the retaining member (5), and workability is improved.

[0017]

EXAMPLE A nominal 25 mechanical pipe joint provided with two kinds of retaining members (5) shown in FIGS. 2A and 2B in which the protrusion angles θ of the blade (5f) were 45 ° and 90 ° was prepared. Typical dimensions of the retaining members (5) shown in FIGS. 2A and 2B are as follows: total length L ₁ = 11 m
m, length L _{2 of} the cylinder inner surface (5d) = 6.2 mm, inner diameter D ₁ of the cylinder inner surface (5 d) = 61.4 mm, outer diameter D _{2 of the} outer end surface (5 g) = 64.9 m
m, and the outer diameter D _{3 of} the inner end surface (5 h) was 71.3 mm. After connecting the nominal 25 steel pipe and vinyl chloride pipe to the connection pipe (6) using the retaining member (5), apply a tensile force from the mechanical pipe joint to the connection pipe (6) using a tensile tester. The pull-out preventing force of the retaining member (5) and the conventional retaining member was measured. As is clear from the measurement results shown in Table 1, it has been found that the mechanical pipe joint according to the present invention has characteristics equivalent to the pull-out prevention force of the conventional joint for exclusive use of pipe types.

[0018]

[Table 1]

[0019]

The mechanical pipe joint according to the present invention is capable of adapting to a plurality of desired pipe types and obtaining a sufficient pull-out preventing force even with different pipe types, and is different according to pipe types having different sizes. It has excellent workability because it is not necessary to replace the cap nut and the retaining member with dimensions.

[Brief description of drawings]

FIG. 1 is a sectional view of a mechanical pipe joint according to the present invention.

FIG. 2 is a sectional view of a retaining member used in the mechanical pipe joint of FIG.

FIG. 3 is a partial cross-sectional view of a mechanical pipe joint of the present invention to which a steel pipe is connected.

FIG. 4 is a partial sectional view of a mechanical pipe joint of the present invention to which a vinyl chloride pipe is connected.

5 is a block diagram showing a manufacturing process of the retaining member shown in FIG.

FIG. 6 is a perspective view showing another embodiment of the retaining member.

FIG. 7 is a cross-sectional view of a retaining member showing an example in which the outer end surface and the inner end surface are curved.

FIG. 8 is a sectional view of a retaining member showing an example in which a curved concave surface is formed on an inner end surface.

FIG. 9 is a cross-sectional view of a conventional retaining member used in a mechanical pipe joint.

[Explanation of symbols]

(1) ・ ・ Coupling body, (1a) ・ ・ Cavity part, (1b) ・ ・ Fitting part end, (1c) ・ ・ Screw part, (2) ・ ・ Cap nut,
(2a) ・ ・ Tapered surface (3) ・ ・ Packing, (4) ・ ・ Washer, (5) ・ ・ Retaining member, (5a) ・ ・ Outer peripheral surface,
(5b) ・ ・ Outer position, (5c) ・ ・ Inner position, (5d) ・ ・ Cylinder inner surface, (5e) ・ ・ Notch, (5f) ・ ・ Flute, (5g) ・ ・
Outer end face, (5h) ・ ・ Inner end face, (6) ・ ・ Connecting pipe, (6a)
··edge,

Claims (4)

[Claims] 1. A joint main body which forms a cavity for inserting a connection pipe, a seal member arranged between the joint main body and an end of the connection pipe, and a screw portion formed at the end of the joint main body. It has a cap nut formed with a threaded portion and a tapered surface to be connected, and a retaining member that prevents the end portion of the connecting pipe from coming out by tightening the cap nut on the joint body. An outer peripheral surface that is formed and contacts the tapered surface of the cap nut, an outer end surface that is arranged on the outer side in the axial direction and is formed in the radial direction, and an inner end surface that is arranged on the inner side in the axial direction and formed in the radial direction. In a mechanical pipe joint with a shrinkable joint gap, the retaining member has a blade protruding radially inward in the vicinity of the inner end face and an outer periphery of the connecting pipe protruding radially inward in the vicinity of the outer end face. The inner surface of the cylinder that contacts the surface and the inner surface of the cylinder When a pair of connecting pipes having a large outer diameter is connected, the cap nut comes into contact with the axially outer position of the outer peripheral surface of the retaining member to prevent the retaining member. When connecting a pair of connecting pipes having a small outer diameter, the cap nut is brought into contact with the axially inner position of the outer peripheral surface of the retaining member to reduce the retaining member. Mechanical type pipe fitting. 2. The mechanical pipe joint according to claim 1, wherein the protrusion angle of the blade is in the range of 30 degrees to 120 degrees. 3. The mechanical pipe joint according to claim 1, wherein the dimensional difference in which the blade protrudes from the inner surface of the cylinder is within 1 mm. 4. The mechanical type according to claim 1, wherein an outer peripheral surface of the retaining member is formed as a tapered surface that continuously changes from an axial outer position to an axial inner position. Pipe fittings.