JP7748909B2 - Pipe joint and flexible pipe connecting method - Google Patents

Description

The technology disclosed in this application relates to a pipe fitting and a method for connecting flexible pipes.

Traditionally, flexible pipes have been widely used for piping within the floors and walls of buildings. A variety of pipe fittings are also used to connect these flexible pipes to gas valves, steel pipes, and other devices. For example, Patent Document 1 discloses a technology in which a flexible pipe is inserted into a pipe fitting, and a packing is used to maintain airtightness, while a retainer is used to hold the valley portion of the flexible pipe and prevent it from coming loose.

Patent No. 5219266

Patent Document 1 states that inserting the flexible pipe to the specified position in the pipe joint is important to maintain airtightness and prevent it from coming loose. However, the insertion state inside the pipe joint cannot be seen. Therefore, the specified position on the flexible pipe must be marked for confirmation, or the insertion must be performed by feel, which can lead to incorrect marking positions or insufficient insertion due to individual differences in insertion feel, etc.

In consideration of the above, the present invention aims to provide a pipe fitting and a method for connecting flexible pipes that allow easy confirmation of the insertion of a flexible pipe when connecting the flexible pipe to the pipe fitting.

A first aspect of the present invention is a pipe fitting for connecting a flexible pipe having at least a corrugated pipe body. The pipe fitting comprises: a cylindrical inner member into which the flexible pipe is inserted from one end in the cylindrical axis direction; an annular inner seal member disposed on the inner periphery of the inner member and sealing between the outer periphery of the corrugated pipe body and the inner periphery of the inner member; a claw member disposed on the inner periphery of the inner member and engaging with the outer periphery of the corrugated pipe body to restrict movement of the corrugated pipe body in the direction opposite to the insertion direction; a position confirmation portion disposed on the inner member that enables visual confirmation from outside the inner member that the tip of the flexible pipe is properly inserted into the inner member; a cylindrical outer member into which the inner member is inserted from one end in the cylindrical axis direction and that holds the inner member within the cylinder; an outer seal member disposed between the inner periphery of the outer member and the outer periphery of the inner member and sealing between the inner periphery of the outer member and the outer periphery of the inner member; and the outer member and the inner member.

The pipe fitting of the first aspect comprises an inner member and an outer member. The inner member is cylindrical, and a flexible pipe is inserted into it from one end in the axial direction of the cylinder. An inner seal member and a claw member are arranged on the inner periphery of the inner member. The inner seal member seals the gap between the flexible pipe and the inner member, and the claw member prevents the flexible pipe from coming loose.

The inner member is inserted into the outer member from one end in the axial direction of the cylinder, holding the inner member within the cylinder. The gap between the inner periphery of the outer member and the outer periphery of the inner member is sealed by an outer seal member.

The inner member is provided with a position confirmation section that allows the operator to visually confirm from the outside that the tip of the flexible tube is inserted into the correct position in the inner member. Therefore, the operator can easily confirm whether the flexible tube is inserted into the correct position in the inner member by directly visually checking the position of the tip of the flexible tube.

In a pipe fitting according to a second aspect of the present invention, the position confirmation portion is provided on the inner side of the insertion direction relative to the outer seal member.

With the second aspect of the pipe fitting, the position confirmation portion is not provided before the insertion of the outer seal member, making it easy to seal between the outer and inner members.

In a third aspect of the pipe fitting of the present invention, the position confirmation portion includes a protrusion that protrudes axially outward from a circumferential portion of the other end of the inner member and is positioned circumferentially outward of the corrugated pipe, and a contact portion formed at the tip of the protrusion that contacts the tip of the corrugated pipe when the flexible pipe is inserted into the correct position in the inner member.

With the third aspect of the pipe fitting, the flexible pipe can be inserted into the appropriate position in the inner member by abutting the tip of the corrugated pipe against the abutment portion formed at the tip of the protrusion.

A fourth aspect of the present invention is a method for connecting a flexible pipe to a pipe fitting according to any one of claims 1 to 3, which involves peeling off the outer sheath from the tip end of the flexible pipe, inserting the flexible pipe into the appropriate position from one end side of the inner member, inserting the inner member into the outer member, and holding the inner member in place in the outer member.

According to the fourth aspect of the flexible pipe connecting method, the flexible pipe is inserted into the appropriate position from one end of the inner member, and after visually confirming that it has been inserted into the appropriate position from the outside of the inner member, the inner member is inserted into the outer member and held in place by the outer member. This makes it easy to confirm that the flexible pipe has been inserted into the appropriate position.

The present invention has the above configuration, making it easy to check whether the flexible pipe is inserted properly when connecting the flexible pipe to the pipe fitting.

FIG. 2 is a half cross-sectional view of the pipe joint of the present embodiment. In this embodiment, (A) is a half cross-sectional view of the inner member, and (B) is a front view of the position confirmation portion. FIG. 2 is a half cross-sectional view of an outer member of the present embodiment. 10 is a perspective view showing a state in which a flexible tube is inserted into an inner member of the present embodiment to an appropriate position. FIG.

The pipe fitting and flexible pipe connecting method of the present invention will be described with reference to the drawings.

Figure 1 shows a half cross-sectional view of a pipe fitting 10 of this embodiment. The pipe fitting 10 is a joint that connects a flexible pipe 12 to other piping, etc. The flexible pipe 12 has a corrugated pipe material 14 and a flat outer skin 16 that covers the outer periphery of the corrugated pipe material 14. The corrugated pipe material 14 is made of a bellows-shaped metal. The outer skin 16 is made of resin with smooth inner and outer surfaces.

The pipe fitting 10 has an inner member 20 and an outer member 40 arranged coaxially. Hereinafter, the central axes of the inner member 20 and the outer member 40 are referred to as S. The inner member 20 is cylindrical and made of metal, with an annular flange portion 22 formed on the outer periphery of one end portion 20A. The outer periphery of the inner member 20 is smooth and has the same outer diameter with no steps except for the flange portion 22. The inner periphery of the inner member 20 has a stepped portion D1, with the inner diameter on the one end portion 20A side being smaller than the inner diameter on the other end portion 20B side.

A seal groove 23 and a claw groove 24 are formed on the inner peripheral surface of one end 20A of the inner member 20. An O-ring 23A is disposed in the seal groove 23. A claw member 25 is disposed in the claw groove 24. The claw member 25 is annular and has a claw 25A that protrudes radially inward. The claw 25A is tapered, gradually decreasing in diameter from the front side toward the back side of the insertion of the flexible pipe 12, and its tip is configured to fit into a valley portion of the bellows-shaped outer surface of the corrugated pipe material 14. When the flexible pipe 12 is inserted, the claw member 25 is pushed by the corrugated pipe material 14 and deforms, expanding its diameter. The claw member 25 can be made of various materials, such as metal, resin, or rubber, as long as it is capable of expanding its diameter.

An inner seal member 26, a coil spring 28, and a position confirmation member 30 are provided on the inner surface of the other end 20B of the inner member 20.

The inner seal member 26 is annular and has a square cross section, and is wide enough to span two adjacent peaks on the bellows-shaped outer surface of the corrugated pipe 14. The inner seal member 26 is positioned along the step D1 and abuts against the peaks on the bellows-shaped outer surface of the corrugated pipe 14, creating a seal between the corrugated pipe 14 and the inner circumference of the inner member 20.

The coil spring 28 is positioned in a compressed state on the side of the inner seal member 26 opposite the stepped portion D1, and by abutting against the position confirmation member 30 (described below), it urges the inner seal member 26 toward the stepped portion D1.

A retaining groove 21 is formed on the inner circumferential surface of the inner member 20 on the other end 20B side. A position confirmation member 30 is held in the retaining groove 21. The position confirmation member 30 has a base end 32, a protrusion 34, and a tip abutment 36. The base end 32 is annular and is bent radially outward to form a convex shape so that it can fit into the retaining groove 21. One end 32A of the base end 32 extends radially inward to a position where it can abut against the coil spring 28. The coil spring 28 is positioned in a compressed state between the one end 32A and the inner seal member 26.

Protrusions 34 are formed on the opposite side of the base end 32 in the direction of the central axis S from the one end 32A. The protrusions 34 extend from four equally spaced locations circumferentially from the other end 32B opposite the one end 32A, and protrude from the other end 20B of the inner member 20. The tips of the protrusions 34 are bent radially inward and formed with tip abutments 36 that are connected to each other. Circumferentially adjacent protrusions 34 are spaced apart. Therefore, openings extending to the tip abutments 36 are formed between adjacent protrusions 34, allowing the tip of the corrugated pipe material 14 of the inserted flexible pipe 12 to be viewed from the outside.

A first outer seal groove 38A, a second outer seal groove 38B, and a third outer seal groove 38C are formed on the outer peripheral surface of the inner member 20. The first outer seal groove 38A is formed in a position corresponding to the claw groove 24. An O-ring 38AO is disposed in the first outer seal groove 38A. The second outer seal groove 38B is formed closer to the other end 20B than the first outer seal groove 38A and closer to the one end 20A than the stepped portion D1. An O-ring 38BO is disposed in the second outer seal groove 38B. The third outer seal groove 38C is formed in a position corresponding to the coil spring 28. An O-ring 38CO is disposed in the third outer seal groove 38C. Hereinafter, O-rings 38AO, 38BO, and 38CO will be collectively referred to as "O-rings 38."

The outer member 40 is cylindrical and made of metal, with an annular flange 42 formed on the outer periphery of one end 40A. Retaining members 43 are provided at multiple locations (six locations in this embodiment) around the circumference of the outer member 40, adjacent to the flange 42 on the side opposite the one end 40A. The retaining members 43 extend from the outer peripheral surface of the outer member 40 beyond the flange 42 toward the one end 40A, and retain the flange 22 of the inner member 20 from the outside in the direction of the central axis S with a return portion 43A formed at the tip.

A hexagonal portion 44 is formed circumferentially on the outer periphery of the other end 40B of the outer member 40, and a male thread 46 is formed on the other end 40B side of the hexagonal portion 44. A stepped portion D2 is formed on the inner periphery of the other end 40B of the outer member 40 in the portion corresponding to the hexagonal portion 44. The stepped portion D2 is formed so that the inner diameter on the other end 40B side is smaller than the inner diameter on the one end 40A side.

Next, we will explain the operation of this embodiment.

When connecting the flexible pipe 12 to the pipe fitting 10, first remove a specified length of the outer sheath 16 from the connecting tip of the flexible pipe 12. The specified length is set so that the length of the corrugated pipe 14 extends from the tip abutment 36 of the position confirmation member 30 provided on the inner member 20, past the claw member 25, to the seal groove 23, and at a position where the claw 25A fits into the valley portion of the accordion-shaped outer surface of the corrugated pipe 14.

Next, the flexible pipe 12, with the outer skin 16 at the tip end removed by a specified length, is inserted into the inner member 20 from the one end 20A side. The corrugated pipe 14 advances toward the other end 20B while elastically deforming the claws 25A of the claw members 25, and moves further toward the insertion depth while abutting against the inner seal member 26. The corrugated pipe 14 is then inserted until its tip abuts against the tip abutment 36 of the position confirmation member 30. The position where the tip of the corrugated pipe 14 protrudes from the other end 20B of the inner member 20 and is clearly visible from the side of the position confirmation member 30 (preferably the position abutting the tip abutment 36) is the correct position for the flexible pipe 12 relative to the inner member 20. The operator can visually confirm from outside the position confirmation member 30 that the flexible pipe 12 is inserted in the correct position in the inner member 20.

When the flexible pipe 12 is inserted into the correct position in the inner member 20, the claws 25A of the claw member 25 fit into the valleys on the accordion-shaped outer surface of the corrugated pipe material 14, preventing the flexible pipe 12 from slipping out of the inner member 20. The inner seal member 26 also creates a seal between the inner periphery of the inner member 20 and the outer periphery of the corrugated pipe material 14, preventing fluid from leaking outside.

With the flexible tube 12 inserted into the appropriate position in the inner member 20, the inner member 20 is inserted into the outer member 40 from one end 40A side. Then, the other end 20B is brought into contact with the stepped portion D2 of the outer member 40, and the flange portion 22 of the inner member 20 is held by the holding member 43.

The other end 40B of the outer member 40 is connected by threading the female thread of the connecting member into the male thread 46.

In the pipe fitting 10 of this embodiment, a position confirmation member 30 is provided so as to protrude from the tip of the inner member 20, so that it is possible to visually confirm from the outside of the inner member 20 whether the tip of the flexible pipe 12 is inserted into the correct position in the inner member 20. Therefore, the worker can easily visually confirm whether the flexible pipe 12 is inserted into the correct position in the inner member 20. If the inner member 20 and the outer member 40 are not separate, a connection portion for connecting another member is provided at the other end 20B of the inner member 20, making it difficult to visually confirm the position of the tip of the flexible pipe 12.

In addition, because the position confirmation member 30 is located further back than the first outer seal groove 38A, the second outer seal groove 38B, and the third outer seal groove 38C, the seal between the outer member 40 and the inner member 20 can be easily achieved even with the position confirmation member 30.

In addition, in this embodiment, the inner member 20 and outer member 40 are separate bodies, so by using an outer member 40 with a different shape on the other end 40B side, the pipe fitting can be made into different shapes. For example, by changing only the outer member 40, pipe fittings such as sockets, elbows, and tee pipes can be made.

In this embodiment, the position confirmation member 30 is provided so as to protrude from the other end 20B of the inner member 20, but an opening may also be provided on the side surface of the other end 20B of the inner member 20, and this opening may serve as the position confirmation member.

In addition, in this embodiment, a configuration in which the flange portion 22 of the inner member 20 is held by the holding member 43 has been described, but other configurations may also be used. For example, the inner member 20 can be held to the outer member 40 by bolting the flange portion 22 and the flange portion 42 together.

In addition, in this embodiment, the first outer seal groove 38A, the second outer seal groove 38B, and the third outer seal groove 38C are formed on the outer peripheral surface of the inner member 20, and O-rings 38AO, 38BO, and 38CO are disposed therein, respectively. However, grooves for disposing O-rings 38AO, 38BO, and 38CO may also be formed on the inner circumference of the outer member 40. Even in this case, a seal can be formed between the inner peripheral surface of the outer member 40 and the outer peripheral surface of the inner member 20.

In addition, while this embodiment describes a flexible pipe 12 having an outer sheath portion 16, the present invention can also be applied to a flexible pipe made only of corrugated pipe material 14 without an outer sheath portion 16.

10 Pipe joint 12 Flexible pipe 14 Corrugated pipe material 16 Outer shell portion 20 Inner member 20A One end portion 20B Other end portion 25 Claw member 25A Claw 26 Inner seal member 30 Position confirmation member (position confirmation portion)
34 Projection part 36 Tip contact part (contact part)
38 O-ring (outer seal member)
40 Outer member 40A One end 40B Other end 43 Holding member S Central axis (cylinder axis)

Claims (4)

A pipe joint for connecting at least a corrugated pipe and a flexible pipe having an outer skin covering the outer periphery of the corrugated pipe ,
an inner member having a cylindrical shape and into which the flexible tube is inserted from one end side in the cylindrical axis direction;
an inner seal member that is annular and disposed on the inner periphery of the inner member, and that seals between the outer periphery of the corrugated pipe and the inner periphery of the inner member;
a claw member disposed on the inner periphery of the inner member and closer to the front side of the inner seal member in the insertion direction of the corrugated pipe, the claw member engaging with the outer periphery of the corrugated pipe to restrict movement of the corrugated pipe in a direction opposite to the insertion direction;
a position confirmation part provided on the inner member, which makes it possible to visually confirm from the outside of the inner member whether the tip of the flexible tube is inserted into the appropriate position of the inner member;
an outer member having a cylindrical shape, into which the inner member is inserted from one end side in the cylindrical axis direction and which holds the inner member within the cylindrical outer member;
an outer seal member disposed between the inner periphery of the outer member and the outer periphery of the inner member, and sealing the gap between the inner periphery of the outer member and the outer periphery of the inner member;
A pipe fitting comprising: A pipe joint for connecting a flexible pipe having at least a corrugated pipe body,
an inner member having a cylindrical shape and into which the flexible tube is inserted from one end side in the cylindrical axis direction;
an inner seal member that is annular and disposed on the inner periphery of the inner member, and that seals between the outer periphery of the corrugated pipe and the inner periphery of the inner member;
a claw member disposed on the inner periphery of the inner member and engaging with the outer periphery of the corrugated tube to restrict movement of the corrugated tube in a direction opposite to the insertion direction;
a position confirmation part provided on the inner member, which makes it possible to visually confirm from the outside of the inner member whether the tip of the flexible tube is inserted into the appropriate position of the inner member;
an outer member having a cylindrical shape, into which the inner member is inserted from one end side in the cylindrical axis direction and which holds the inner member within the cylindrical outer member;
an outer seal member disposed between the inner periphery of the outer member and the outer periphery of the inner member, and sealing the gap between the inner periphery of the outer member and the outer periphery of the inner member;
Equipped with
The position confirmation portion has a protruding portion that protrudes outward in the axial direction from a circumferential portion of the other end portion of the inner member and is positioned on the circumferential outer side of the corrugated tube, and an abutting portion that is formed at a tip of the protruding portion and against which the tip of the corrugated tube abuts when the flexible tube is inserted into the appropriate position of the inner member.
Pipe fittings. 3. The pipe joint according to claim 1, wherein the position confirmation portion is provided on a rear side of the outer seal member in the insertion direction . A method for connecting a flexible pipe to the pipe joint according to any one of claims 1 to 3, comprising:
Inserting the flexible tube into the appropriate position from one end side of the inner member;
The inner member is inserted into the outer member and held by the outer member.
How to connect flexible pipes.