A set of pipe with a sheath and a pipe fitting.

Abstract

To provide a pipe with a sheath tube.SOLUTION: A pipe with a sheath tube 21 comprises a sheath tube 23 and a pipe body 22. A pipe joint 11 comprises a holding ring 15 that bites into an outer peripheral surface of the pipe body 22 exposed from the sheath tube 23 to prevent the pipe body 22 from coming off of the pipe joint 11. An outer diameter of a bottom 26a of a recess part 26 in the sheath tube 23 is smaller than the maximum inner diameter on an opening side of a pipe insertion port 16a of the pipe joint 11, and larger than the minimum inner diameter on a back side of the pipe insertion port 16a.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a pipe with a sheath tube used for water supply, hot water supply, etc. and the combination of pipe fittings It relates to.

Background Art

[0002] Patent Document 1 discloses a corrugated tube through which a flexible tube for water supply and hot water supply is inserted. Patent Document 2 discloses a resin pipe in which circumferences serving as insertion marks for a pipe joint are drawn at equal intervals in the extending direction of the axis.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a novel pipe with a sheath tube. and the combination of pipe fittings To provide.

Means for Solving the Problems

[0005] In order to achieve the above object, the pipe with a sheath tube according to the invention of claim 1 and the combination of pipe fittings is a pipe with a sheath tube comprising a sheath tube having a bellows shape in which convex portions and concave portions are alternately arranged in the extending direction of the axis and being stretchable in the extending direction, and a pipe body inserted into the sheath tube. A combination of a pipe with a sheath and a pipe fitting, which has a pipe insertion port into which the pipe body is inserted and the pipe body is connected. and , the above The pipe joint includes a holding ring that bites into the outer peripheral surface of the pipe body exposed from the sheath tube to suppress the pipe body from coming out of the pipe joint. ,before In the sheath tube, the outer diameter of the bottom of the concave portion is The aforementionedThe inner diameter is smaller than the maximum inner diameter on the opening side of the pipe insertion port, larger than the minimum inner diameter on the back side of the pipe insertion port, and the same as the inner diameter in between the opening side and the back side of the pipe insertion port. [Brief explanation of the drawing]

[0006] [Figure 1] Side view of a pipe with a sheath tube. [Figure 2] Side view of the pipe body. [Figure 3] Side view of the sheath tube. [Figure 4] Longitudinal cross-sectional view of a pipe joint. [Figure 5] A longitudinal cross-sectional view of a pipe fitting with a pipe with a sheath tube inserted. [Modes for carrying out the invention]

[0007] The following describes one embodiment of the present invention. First, let's explain pipe fittings to which pipes with sheath tubes are connected.

[0008] As shown in Figure 4, a through hole 12a is formed in the joint body 12 that constitutes the pipe joint 11. A stepped portion 12b is formed on the inner circumferential surface of one end (left end in the drawing) of the through hole 12a. The flange portion 13a of the inner cylinder 13, which is inserted into the through hole 12a from the other end (right end in the drawing), abuts against the stepped portion 12b. Multiple annular grooves 12c are formed on the inner circumferential surface of the through hole 12a. Each annular groove 12c houses a seal ring 14.

[0009] A stepped portion 12d is formed on the inner circumferential surface of the other end of the through hole 12a. A retaining ring 15 having retaining claws 15a is locked to the stepped portion 12d. A female threaded portion 12e is formed on the inner circumferential surface of the other end of the through hole 12a. A tightening ring 16 is screwed into the female threaded portion 12e. The outer circumferential edge of the retaining ring 15 is held in a predetermined position by the stepped portion 12d and the tightening ring 16. An insertion space 17 is formed between the outer circumferential surface of the inner cylinder 13 and the inner circumferential surfaces of the joint body 12 and the tightening ring 16.

[0010] As shown in Figure 5, the pipe body 22 of the pipe with sheath tube 21 is positioned in the insertion space 17 of the pipe fitting 11, thereby connecting the pipe fitting 11 and the pipe body 22. When the pipe fitting 11 and the pipe body 22 are connected, the retaining claws 15a of the retaining ring 15 bite into the outer surface of the pipe body 22, preventing the pipe body 22 from coming out of the pipe fitting 11.

[0011] In the drawing, "L" indicates the appropriate insertion depth of the pipe body 22 in the insertion space 17. In the drawing, "M" indicates the maximum inner diameter of the opening (pipe insertion port) 16a located on the insertion side (right end of the drawing) of the tightening ring 16.

[0012] Next, we will describe the pipe 21 with a sheath tube. As shown in Figure 1, the pipe with a sheath pipe 21 comprises a pipe body 22 and a sheath pipe 23 into which the pipe body 22 is loosely inserted. The central axis S of the pipe body 22 and the sheath pipe 23 are approximately coincident. The sheath pipe 23 protects the pipe body 22 from being stepped on during construction, ensures the weather resistance of the pipe body 22, and is also used in sheath pipe construction methods to facilitate future replacement of the pipe body 22.

[0013] As shown in FIG. 2, the pipe body 22 is made of a synthetic resin such as crosslinked polyethylene or polybutene, and is formed into a flexible circular tube shape. A plurality of insertion marks 22a are attached to the outer peripheral surface of the pipe body 22 by printing at equal intervals in the extending direction of the axis S (the left - right direction in the drawing). "K" in the drawing indicates the interval (size). The interval K of the insertion marks 22a is the same as the insertion depth L of the pipe body 22 with respect to the pipe joint 11 (see FIG. 5).

[0014] As shown in FIG. 3, the sheath tube 23 is made of a synthetic resin such as polypropylene, polyethylene, or polyamide, and is formed into a flexible circular tube shape. The sheath tube 23 is colorless transparent or colored transparent. Examples of colored transparent include blue transparent considering its adoption in the water path of a water supply and hot water supply pipe, red transparent considering its adoption in the hot water path, or white transparent considering its versatility.

[0015] The sheath tube 23 has an annular convex portion 25 and an annular concave portion 26 alternately arranged in the extending direction of the axis S, forming a bellows shape. That is, it can be said that the sheath tube 23 is a corrugated tube that can expand and contract in the extending direction of the axis S.

[0016] The tip 25a of the convex portion 25 is the portion where the inner and outer diameters of the sheath tube 23 are the largest. The bottom 26a of the concave portion 26 is the portion where the inner and outer diameters of the sheath tube 23 are the smallest. The wall thickness of the tip 25a in the convex portion 25 is smaller than the wall thickness of the bottom 26a in the concave portion 26.

[0017] The tip 25a of the convex portion 25 extends straight (maintaining the same diameter) in the extending direction of the axis S. The bottom 26a of the concave portion 26 extends straight in the extending direction of the axis S. The adjacent convex portion 25 and concave portion 26 are connected via boundary walls 25b, 26b where the tip 25a and the bottom 26a extend continuously in a direction perpendicular to the axis S.

[0018] In the drawings, "N" indicates the outer diameter of the bottom 26a in the recess 26. As shown in FIG. 5, this outer diameter N is smaller than the inner diameter M of the pipe insertion port 16a in the clamping ring 16 of the pipe joint 11. Therefore, when the tip of the sheath tube 23 facing the pipe joint 11 is provided by the bottom 26a of the recess 26, in the state where the pipe joint 11 and the pipe body 22 are connected, it is possible to position the bottom 26a within the pipe insertion port 16a of the clamping ring 16.

[0019] In FIGS. 1 and 3, "P" indicates the distance between the centers in the extending direction of the axis S between the tip 25a of the convex portion 25 and the bottom 26a of the recess 26 in the sheath tube 23. As shown in FIG. 1, the distance K between the insertion marks 22a on the pipe body 22 is an odd multiple of the distance P between the convex portion 25 and the recess 26 of the sheath tube 23.

[0020] As shown in FIG. 1, assume that the sheath tube 23 and the pipe body 22 are positioned in the extending direction of the axis S such that one insertion mark 22a (22a - 1) of the pipe body 22 appears to overlap with respect to the bottom 26a of the recess 26 in the sheath tube 23 in a direction perpendicular to the axis S. In this positioned state, another insertion mark 22a (22a - 2) adjacent to the one insertion mark 22a (22a - 1) appears to overlap with respect to the tip 25a of the convex portion 25 in a direction perpendicular to the axis S.

[0021] Although not shown, conversely, assume that the sheath tube 23 and the pipe body 22 are positioned such that one insertion mark 22a (22a - 1) of the pipe body 22 appears to overlap with respect to the tip 25a of the convex portion 25 in the sheath tube 23. In this positioned state, another insertion mark 22a (22a - 2) adjacent to the one insertion mark 22a (22a - 1) appears to overlap with respect to the bottom 26a of the recess 26.

[0022] Furthermore, although not shown in the figures, in another example of this embodiment, the spacing K of the insertion marks 22a may be an even multiple of the spacing P between the convex portion 25 and the concave portion 26 in the sheath tube 23. In this case, the sheath tube 23 and the pipe body 22 are positioned in the direction of extension of the axis S such that one insertion mark 22a (22a-1) of the pipe body 22 appears to overlap with the bottom 26a of the concave portion 26 in the sheath tube 23 in a direction perpendicular to the axis S. In this positioning state, another insertion mark 22a (22a-2) adjacent to the first insertion mark 22a (22a-1) appears to overlap with the bottom 26a of a concave portion 26 other than the first concave portion 26 in a direction perpendicular to the axis S.

[0023] Conversely, suppose the sheath tube 23 and the pipe body 22 are positioned such that one insertion mark 22a (22a-1) of the pipe body 22 appears to overlap with the tip 25a of a protrusion 25 in the sheath tube 23. In this positioning state, another insertion mark 22a (22a-2) adjacent to the first insertion mark 22a (22a-1) appears to overlap with the tip 25a of a protrusion 25 that is different from the first protrusion 25.

[0024] Next, an example of the process of connecting a pipe 21 with a sheath to a pipe fitting 11 will be explained.

[0025] As shown in Figure 4, a pipe with a sheath tube 21 is connected to the pipe fitting 11. In this case, as shown in Figure 1, the sheath tube 23 and the pipe body 22 are positioned in the direction of extension of the axis S such that one of the insertion marks 22a (22a-1) on the pipe body 22 appears to overlap with the bottom 26a of the recess 26 on the sheath tube 23 in a direction perpendicular to the axis S. In this state, the sheath tube 23 and the pipe body 22 are cut in one swift motion with a tool, using the one insertion mark 22a (22a-1) visible through the bottom 26a of the recess 26 on the sheath tube 23 as a guide.

[0026] As shown in Figure 5, after cutting the sheath pipe 23 and the pipe body 22, the tip (cut end) of the pipe body 22 is inserted into the insertion space 27 of the pipe fitting 11. If it can be confirmed by passing through the sheath pipe 23 that another insertion mark 22a (22a-2), which is adjacent to the first insertion mark 22a (22a-1) at a distance K, has moved to the end of the pipe fitting 11, that is, to the pipe insertion opening 16a of the tightening ring 16, then it can be determined that the insertion allowance of the pipe body 22 into the pipe fitting 11 is approximately equal to the insertion depth L of the pipe fitting 11, and that the connection is in a proper state.

[0027] The above embodiment provides the following effects. (1) The sheath tube 23 is transparent. Therefore, when cutting the pipe body 22, there is no need to expose one insertion mark 22a (22a-1) from the sheath tube 23. Also, when inserting the pipe body 22 into the pipe fitting 11, there is no need to expose another insertion mark 22a (22a-2) from the sheath tube 23.

[0028] (2) For example, if the sheath pipe 23 and the pipe body 22 are positioned such that one insertion mark 22a(22a-1) of the pipe body 22 appears to overlap with the bottom 26a of the recess 26 in the sheath pipe 23, then another insertion mark 22a(22a-2) adjacent to the first insertion mark 22a(22a-1) will appear to overlap with the tip 25a of the protrusion 25. Therefore, the visibility of these insertion marks 22a(22a-1,22a-2) is improved compared to the case where they appear to overlap with the radially thick boundary walls 25b,26b.

[0029] Therefore, the sheath tube 23 and the pipe body 22 can be accurately cut using the first insertion mark 22a (22a-1) as a guide. Furthermore, when confirming another insertion mark 22a (22a-2) after the cutting, there is no need to reposition the tip 25a of the protrusion 25 or the bottom 26a of the recess 26 to clearly confirm the other insertion mark 22a (22a-2), allowing for a smooth transition from the cutting process to the insertion process.

[0030] In Figure 1, insertion marker 22a(22a-3), which is far from the first insertion marker 22a(22a-1), appears to overlap with the radially thick boundary walls 25b and 26b, rather than the tip 25a of the convex portion 25 or the bottom 26a of the concave portion 26, resulting in poor visibility. However, insertion marker 22a(22a-3) has little practical use in this construction, and poor visibility does not pose any problem.

[0031] In that sense, the statement "the spacing K of the insertion marks 22a is an odd or even multiple of the spacing P between the convex portion 25 and the concave portion 26" is not limited to being exactly an odd or even multiple and all insertion marks 22a appearing to overlap the tip 25a of the convex portion 25 or the bottom 26a of the concave portion 26. It is sufficient that one insertion mark 22a (22a-1) used in the cutting process and another insertion mark 22a (22a-2) used in the insertion process appear to overlap the tip 25a of the convex portion 25 or the bottom 26a of the concave portion 26.

[0032] (3) When the pipe fitting 11 and the pipe body 22 are connected, the bottom 26a of the recess 26 in the sheath pipe 23 may be located inside the pipe insertion opening 16a of the pipe fitting 11. Therefore, the pipe body 22 is less likely to be exposed from the sheath pipe 23 and the pipe fitting 11, improving the appearance of the construction site and extending the lifespan of the pipe body 22 by making it less susceptible to the effects of ultraviolet rays, etc.

[0033] Thus, when the bottom 26a of the recess 26 in the sheath pipe 23 is located inside the pipe insertion port 16a of the pipe fitting 11, the sheath pipe 23 is more likely to catch on the pipe fitting 11 (tightening ring 16) when withdrawing it from the pipe insertion port 16a, compared to when it is not located there. In this sense, the transparency of the sheath pipe 23 is particularly effective in subsequent inspections such as construction confirmation, as it allows for transparent confirmation of the positional relationship between another insertion marker 22a (22a-2) and the pipe insertion port 16a without having to withdraw the sheath pipe 23 from the pipe insertion port 16a.

[0034] (4) In the sheath tube 23, the tip 25a of the protrusion 25 has a small wall thickness. Therefore, even though the tip 25a is located radially away from the pipe body 22, the visibility of the insertion mark 22a, which appears to overlap the tip 25a, is good. In addition, the bottom 26a of the recess 26 in the sheath tube 23 has a large wall thickness, which contributes to improving the durability of the sheath tube 23. Since the bottom 26a is located radially close to the pipe body 22, even if the wall thickness of the bottom 26a is large, the visibility of the insertion mark 22a, which appears to overlap the bottom 26a, is good. In order to achieve both of these at a high level, it is preferable that the wall thickness of the bottom 26a in the recess 26 be about 1.2 to 2 times that of the wall thickness of the tip 25a in the protrusion 25.

[0035] (Another example) The above embodiment can be modified as follows, for example. ○ The tip 25a of the protrusion 25 is curved (so that its diameter changes) in the direction of extension of the axis S.

[0036] ○ The bottom 26a of the recess 26 is curved and extends in the direction of extension of the axis S.

[0037] ○ The outer diameter of the tip 25a of the protrusion 25 of the sheath pipe 23 is made smaller than the inner diameter M of the pipe insertion opening 16a of the pipe fitting 11. In this way, even if the tip of the sheath pipe 23 facing the pipe fitting 11 is provided by the tip 25a of the protrusion 25, when the pipe fitting 11 and the pipe body 22 are connected, the tip 25a can be positioned inside the pipe insertion opening 16a of the tightening ring 16.

[0038] (Note) The technical concepts that can be understood from the above embodiments are described below. (1) A pipe with a sheath tube, comprising a sheath tube made of a transparent resin material that is bellows-shaped with convex and concave portions alternately arranged in the direction of extension of the axis and is expandable and contractible in the direction of extension, and a pipe body inserted into the sheath tube and having a plurality of insertion marks for a pipe joint attached at equal intervals in the direction of extension, wherein the pipe joint is provided with a retaining ring that bites into the outer surface of the pipe body exposed from the sheath tube to prevent the pipe body from coming out of the pipe joint, and the outer diameter of the bottom of the concave portion of the sheath tube is smaller than the maximum inner diameter on the opening side of the pipe insertion port of the pipe joint and larger than the minimum inner diameter on the inner side of the pipe insertion port. With this configuration, since the sheath tube is transparent, there is no need to expose the insertion mark on the main pipe body from the sheath tube when checking the insertion mark. [Explanation of Symbols]

[0039] 11...Pipe fitting, 16a...Pipe insertion port, 21...Pipe with sheath tube, 22...Pipe body, 22a...Insertion marker, 22a-1...First insertion marker, 22a-2...Another insertion marker, 23...Sheath tube, 25...Protrusion, 25a...Tip, 26...Concave, 26a...Bottom.

Claims

[Claim 1] A pipe with a sheath tube and a pipe fitting comprising a sheath tube having a bellows-like shape with convex and concave portions alternately arranged in the direction of extension of the axis and being expandable and contractible in the direction of extension, and a pipe body inserted through the sheath tube, and a pipe fitting having a pipe insertion port into which the pipe body is inserted and the pipe body is connected, the pipe fitting and the pipe fitting comprising The pipe joint is equipped with a retaining ring that bites into the outer surface of the pipe body exposed from the sheath pipe, thereby preventing the pipe body from coming out of the pipe joint. A pipe with a sheath tube and a pipe fitting, wherein the outer diameter of the bottom of the recess in the sheath tube is smaller than the maximum inner diameter on the opening side of the pipe insertion port of the pipe fitting, larger than the minimum inner diameter on the far side of the pipe insertion port, and the same as the inner diameter in between the opening side and the far side of the pipe insertion port.

Images