Pipe fittings

Abstract

To provide a pipe joint that shortens the time it takes for a water-sealing member with a water-absorbing and expanding function to exert its water-sealing effect. [Solution] The pipe joint 10 comprises a joint body in which a watertight portion is formed between it and the pipe body 20, an annular watertight member disposed in the watertight portion and having a water absorption and expansion function, and a water contact area increasing portion formed on the watertight member that increases the contact area between the water that has entered the watertight portion and the watertight member, thereby causing the watertight member to expand radially.

Description

Technical Field

[0001] The present invention relates to a pipe joint for connecting pipe bodies.

Background Art

[0002] Conventionally, a pipe joint is known in which a water-stop member such as an O-ring is arranged on a water-stop surface between a pipe body and a joint to stop water. Also, as a water-stop member, a water-absorbing expansion sealing material that expands by absorbing water and seals the water-stop surface has been proposed for leak prevention measures (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when a water-absorbing expansion sealing material is used, the water-stop function is not exhibited until the water-absorbing expansion sealing material expands, so it is necessary to shorten the time until the expansion time.

[0005] In consideration of the above facts, an object of the present invention is to provide a pipe joint that shortens the time until the water-stop function is exhibited by a water-stop member having a water-absorbing expansion function.

Means for Solving the Problems

[0006] In order to solve the above problems, the present invention proposes the following means.

[0007] The pipe joint according to the first embodiment comprises a tubular joint body connected to a pipe body, with a watertight portion formed between it and the pipe body; an annular watertight member disposed in the watertight portion and having a water-absorbing and expanding function; and a watertight surface area increasing portion formed on the watertight member, which increases the contact area between the water that has entered the watertight portion and the watertight member, thereby causing the watertight member to expand radially.

[0008] In the pipe joint of the first embodiment, a portion for increasing the contact area with water is formed on the water-sealing member. The portion for increasing the contact area with water increases the contact area between the water-sealing member and the water that has entered the water-sealing portion, causing the water-sealing member to expand radially. Therefore, compared to the case in which the portion for increasing the contact area with water is not formed, the expansion of the water-sealing member in the radial direction is promoted, and the time until the water-sealing function is achieved can be shortened.

[0009] In the pipe joint according to the second embodiment, the portion with increased water contact area is formed by a slit extending along the axial direction of the water-stopping member.

[0010] According to the pipe joint of the second embodiment, water can be allowed to enter the portion where the slit is formed, thereby increasing the water-contact area of ​​the water-stopping member.

[0011] In the third embodiment of the pipe joint, the slit is formed extending from the upstream end of the water-stopping member in the direction of water infiltration.

[0012] According to the pipe joint of the third embodiment, water can easily penetrate the slit, and the expansion rate of the water-stopping member can be increased.

[0013] In the fourth embodiment of the pipe joint, the slit is formed around the entire circumference in the radially intermediate portion of the water-stopping member.

[0014] According to the pipe joint of the fourth embodiment, the expansion of the water-stopping member radially outward across the slit can be effectively promoted.

[0015] In the fifth embodiment of the pipe joint, the slit is formed with a length of 1 / 2 or more of the axial length of the water-stopping member.

[0016] According to the pipe joint according to the fifth aspect, in the axial direction of the water stop member, water can be sufficiently infiltrated, and the expansion of the water stop member can be effectively promoted.

Effect of the Invention

[0017] According to the present invention, the time until the water stop function is exerted by the water stop member having a water absorption expansion function can be shortened.

Brief Description of the Drawings

[0018] [Figure 1] Regarding the pipe joint according to the first embodiment, (A) is a cross-sectional view showing the state before the pipe body is inserted, and (B) is a cross-sectional view showing the state after the pipe body is inserted. [Figure 2] It is a cross-sectional view of the joint main body part and the water stop member of the pipe joint according to the first embodiment. [Figure 3] It is a perspective view of the water stop member of the pipe joint according to the first embodiment. [Figure 4] It is a view of the water stop member according to the modification example as viewed from the axial direction. [Figure 5] Regarding the water stop member according to another modification example, (A) is a view as viewed from the axial direction, and (B) is a perspective view. [Figure 6] (A) and (B) are partial cross-sectional views of the water stop member according to another modification example. [Figure 7] Regarding the pipe joint according to the second embodiment, (A) is a cross-sectional view showing the state before the pipe body is inserted, and (B) is a cross-sectional view showing the state after the pipe body is inserted.

Modes for Carrying Out the Invention

[0019] Hereinafter, the pipe joint according to the embodiment of the present invention will be specifically described while referring to the accompanying drawings.

[0020] [First Embodiment] The pipe joint 10 of the first embodiment includes a joint main body portion 30 and a joint peripheral portion 40. The joint main body portion 30 has a cylindrical inner cylinder portion 31 and a connection portion 32 formed continuously at one end of the inner cylinder portion 31. A screw portion is formed on the outer peripheral surface of the connection portion 32 so that it can be screwed and connected to another pipe body. Between the inner cylinder portion 31 and the connection portion 32, a hexagonal portion 32A having a larger outer diameter than the inner cylinder portion 31 and the connection portion 32 is formed. Also, a flow path R is formed on the inner peripheral side of the inner cylinder portion 31 and the connection portion 32.

[0021] The joint peripheral portion 40 has a cylindrical holding member 41, a ring-shaped claw member 42, a release ring 43, and a cap 44. The holding member 41 is disposed on the outer peripheral side of the inner cylinder portion 31, and the claw member 42 and the release ring 43 are arranged in parallel at one end of the holding member 41. The cap 44 is installed so as to cover these holding member 41, claw member 42, and release ring 43 from the outer peripheral side, preventing the holding member 41, claw member 42, and release ring 43 from coming out of the joint main body portion 30.

[0022] A pipe body insertion space 21 into which the pipe body 20 is inserted is formed between the inner cylinder portion 31 and the holding member 41. The pipe body 20 inserted into the pipe body insertion space 21 is prevented from coming out by the claw member 42 attached to one end of the holding member 41 biting into the outer periphery. By pushing the release ring 43 provided together with the claw member 42 toward the claw member 42 side to expand the diameter of the claw member 42 and release the biting, the pipe body 20 can be pulled out from the pipe body insertion space 21. Also, the end portion of the inner cylinder portion 31 on the connection portion 32 side has an enlarged flange portion 33, and the pipe body 20 can be inserted until it reaches this flange portion 33.

[0023] Hereinafter, the direction along the axis L of the inner cylinder portion 31 is referred to as the axial direction, and the direction orthogonal to the axis L is referred to as the radial direction. Also, regarding the axial direction of the pipe joint 10, the connection portion 32 side is referred to as the back side, and the pipe body 20 side is referred to as the front side. <00​​The outer circumferential surface of the inner cylinder portion 31 has circumferential grooves 34 and 35 formed therein, which are recesses extending around the entire circumference. The circumferential groove 34 is formed closer to the tip of the inner cylinder portion 31 than the circumferential groove 35. The circumferential groove 35 is longer in the axial direction L than the circumferential groove 34. An O-ring 36 is fitted into the circumferential groove 34, and a water-sealing ring 37 is fitted into the circumferential groove 35. The area including the circumferential grooves 34 and 35 and their vicinity on the outer circumferential surface of the inner cylinder portion 31 forms a water-sealing section.

[0025] The O-ring 36 is primarily made from materials that do not absorb water and swell, or have low water absorption and swelling properties, such as SBR, EPDM, CR, butyl rubber, silicone, polysulfur rubber, and chlorosulfonated polyethylene rubber.

[0026] As shown in Figures 2 and 3, the water-sealing ring 37 has a rectangular cross-section and is an annular shape. The water-sealing ring 37 has a water-absorbing and swelling function and is formed by including a water-absorbing and swelling material. Examples of water-absorbing and swelling materials include rubber that absorbs water and swells itself, such as urethane rubber, non-swelling rubbers such as NBR, SBR, and EPDM, and mixtures of polyacrylic acid-based, popal-based, polyoxyethylene-based, cellulose-based, and starch-based superabsorbent resins with EVA resin or polyvinyl chloride resin.

[0027] As shown in Figure 2, before being fitted into the circumferential groove 35, the inner diameter R1 of the water-sealing ring 37 is smaller than the diameter R2 of the bottom of the circumferential groove 35. Therefore, when attaching the water-sealing ring 37 to the circumferential groove 35, the inner diameter of the water-sealing ring 37 is stretched by elastic deformation, and even after attachment, it is fitted in a slightly stretched state.

[0028] As shown in Figure 3, a slit 37A is formed in the water-sealing ring 37. The slit 37A is formed in a circular shape around the entire circumference in the radial middle portion, i.e., the central part of the thickness, when viewed from the axial direction. The slit 37A is formed from the upstream end of the water-sealing ring 37 in the direction of water intrusion when viewed from the side, and is formed to a length S that does not extend to the other end. Preferably, the axial length S of the slit 37A is 1 / 2 or more of the axial length of the water-sealing ring 37.

[0029] Next, the operation of the pipe joint 10 will be explained.

[0030] As shown in Figure 1(A), the pipe 20 is positioned facing the opening side of the pipe insertion space 21. Then, as shown in Figure 1(B), it is inserted until the tip abuts against the flange portion 33. In this inserted state, the O-ring 36 is compressed by the bottom of the circumferential groove 34 and the pipe 20, sealing the space between the outer surface of the inner cylinder portion 31 and the inner surface of the pipe 20. The claw member 42 bites into the outer surface of the pipe 20, preventing the pipe 20 from coming out.

[0031] In this state, for example, if foreign matter (such as a strand of hair) is caught in the O-ring 36, water leakage will occur. The water leakage occurs as water gradually seeps in from the front to the back of the inner cylinder 31 and reaches the water-sealing ring 37. Since the water-sealing ring 37 has a water-absorbing and expanding function, it expands and seals the space between the outer surface of the inner cylinder 31 and the inner surface of the pipe 20.

[0032] In this embodiment, the water-sealing ring 37 has a slit 37A formed in it. As a result, water that enters the circumferential groove 35 enters the slit 37A, increasing the area in direct contact with water (water-contacting area) of the water-sealing ring 37. Compared to a case where the slit 37A is not formed, the expansion of the water-sealing ring 37 is accelerated, and the time until the water-sealing function is achieved can be shortened.

[0033] Furthermore, since the slit 37A in this embodiment is formed from the upstream end in the water ingress direction, water can easily enter the slit 37A, shortening the time until the water-stopping function is activated.

[0034] Furthermore, since the slit 37A in this embodiment is formed over the entire circumference in the middle of the radial direction when viewed from the axial direction, it can effectively promote the expansion of the water-sealing ring 37 radially outward across the slit 37A.

[0035] Furthermore, since the water-stopping ring 37 of this embodiment is fitted into the circumferential groove 35 with its inner diameter stretched by elastic deformation, even if the inner diameter increases due to radial outward expansion, a gap is less likely to form between the ring and the bottom of the circumferential groove 35.

[0036] In this embodiment, the slit 37A is formed around the entire circumference of the water-stopping ring 37, but as shown in Figure 4, it may also be formed as a slit 37B divided into multiple sections.

[0037] Alternatively, as shown in Figures 5(A) and 5(B), it may be formed as a plurality of slits 37C extending radially outward from the radially intermediate portion.

[0038] Alternatively, as shown in Figure 6(A), a recess 38 may be formed in place of the slit 37A of the water-stopping ring 37. The recess 38 is formed at the upstream end in the direction of water infiltration. Viewed from the axial direction, the recess 38 is formed in a circular shape around its entire circumference in the radial middle portion, i.e., the central portion of its thickness.

[0039] In this way, by forming the recess 38, the water that has entered will enter the recess 38, increasing the area in direct contact with the water (water-contacting area) of the water-stopping ring 37. As a result, the expansion of the water-stopping ring 37 is accelerated compared to when the recess 38 is not formed, and the time until the water-stopping function is achieved can be shortened.

[0040] As shown in Figure 6(B), a slit 38A may be formed so as to be continuous with the inner side of the recess 38.

[0041] [Second Embodiment] Next, a second embodiment will be described. In this embodiment, the same parts as in the first embodiment are denoted by the same reference numerals, and their detailed descriptions will be omitted. The pipe joint 50 in this embodiment seals the outer surface of the pipe body 20.

[0042] As shown in Figures 7(A) and 7(B), the pipe fitting 50 comprises a fitting body 52, an inner circumferential support member 53, a cap 54, a collet 56, an O-ring 36, and a water-stopping ring 37.

[0043] The joint body 52 is cylindrical and consists of a first inner wall portion 52A, a second inner wall portion 52B, and a third inner wall portion 52C, in order from the insertion side of the pipe body 20. The inner diameter of the first inner wall portion 52A is larger than the inner diameter of the second inner wall portion 52B, and the inner diameter of the second inner wall portion 52B is larger than the inner diameter of the third inner wall portion 52C. The third inner wall portion 52C forms part of the flow path. A stepped portion 52D1 is formed between the first inner wall portion 52A and the second inner wall portion 52B, and a stepped portion 52D2 is formed between the second inner wall portion 52B and the third inner wall portion 52C. A male thread 52N is formed on the outer circumference of the joint body 52 corresponding to the first inner wall portion 52A.

[0044] The cap portion 54 is annular in shape, and a female thread 54N is formed on its inner wall that screws onto the male thread 52N. The cap portion 54 is connected to the joint body 52 by the female thread 54N screwing onto the male thread 52N. On the side of the cap portion 54 that is inserted into the pipe body 20, an insertion opening portion 54A is formed, which has a smaller inner diameter than the first inner wall portion 52A of the joint body 52.

[0045] Inside the first inner wall portion 52A, between the insertion opening portion 54A and the stepped portion 52D, a collet 56, a watertight ring 37, and an O-ring 36 are arranged in that order from the insertion opening portion 54A. The slit 37A of the watertight ring 37 is positioned on the side of the O-ring 36. The collet 56 is annular in shape and prevents the watertight ring 37 and the O-ring 34 from coming off and positions them.

[0046] The inner circumferential support member 53 is cylindrical in shape with a flange 53A formed at its tip. The flange 53A abuts against the stepped portion 52D, and an insertion space 51 is formed between the inner circumferential support member 53 and the collet 56.

[0047] Next, the function of the pipe joint 50 will be explained.

[0048] As shown in Figure 7(A), the pipe body 20 is positioned opposite the insertion opening 54A. Then, as shown in Figure 7(B), the pipe body 20 is inserted into the insertion space 51, and its tip is brought into contact with the stepped portion 52D2. In this inserted state, the O-ring 36 is compressed by the first inner wall portion 52A and the pipe body 20, sealing the space between the first inner wall portion 52A and the outer surface of the pipe body 20.

[0049] In this state, for example, if foreign matter (such as hair) is caught in the O-ring 36, water leakage will occur. Due to the water leakage, water gradually seeps in from the third inner wall portion 52C side of the O-ring 36 to the water-sealing ring 37 side. Since the water-sealing ring 37 has a water-absorbing and expanding function, it expands and seals the space between the outer surface of the first inner wall portion 52A and portion 31 and the inner surface of the pipe body 20.

[0050] In this embodiment, the water-sealing ring 37 also has a slit 37A formed in it. As a result, water that enters enters the slit 37A, increasing the area in direct contact between the water-sealing ring 37 and the water (water-contacting area). Compared to cases where the slit 37A is not formed, the expansion of the water-sealing ring 37 is accelerated, and the time until the water-sealing function is achieved can be shortened.

[0051] Furthermore, since the slit 37A in this embodiment is formed at the upstream end in the water ingress direction, water can easily enter the slit 37A, thereby shortening the time required for the water-stopping function to be activated.

[0052] Although the first and second embodiments of the present invention have been described above, the components in the above embodiments can be replaced with other components as appropriate without departing from the spirit of the present invention, and the above embodiments can also be combined as appropriate. [Explanation of Symbols]

[0053] 10, 50 pipe fittings 20 tubular body 30 Joint body 37. Water-stopping ring (water-stopping component) 37A Slit (part for increasing the contact area with water) 37B Slit (part for increasing the contact area with water) 37C Slit (Increased water contact area) 38 Recess (area with increased water contact area) 38A Slit (part for increasing the contact area with water)

Claims

1. A tubular joint body that connects to a pipe and forms a watertight seal between it and the pipe, An annular water-stopping member having a water-absorbing and expanding function is placed in the water-stopping section, A water-contacting surface area increasing portion is formed on the water-stopping member, which increases the contact area between the water that has entered the water-stopping portion and the water-stopping member, causing the water-stopping member to expand radially, A pipe fitting equipped with [a specific feature].

2. The portion with increased water contact area is formed by a slit extending along the axial direction of the water-stopping member. The pipe fitting according to claim 1.

3. The slit extends from the upstream end of the water-stopping member in the direction of water intrusion, The pipe fitting according to claim 2.

4. The slit is formed around the entire circumference in the radially intermediate portion of the water-stopping member. The pipe fitting according to claim 2.

5. The slit is formed in the axial direction of the water-stopping member with a length of 1 / 2 or more of the length. The pipe fitting according to claim 2.

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