JP7376277B2 - Corrugated double pipe and water pipe equipment - Google Patents

Description

The present invention relates to a corrugated double pipe having a two-layer structure and a water pipe device including the corrugated double pipe.

2. Description of the Related Art Conventionally, water pipes made of flexible pipes made of synthetic resin materials have been installed in buildings to supply hot water to hot water consumption sides such as toilets and baths. For example, hot water or cold water flows through the water pipe. Further, the water pipe is inserted into a protection pipe made of a synthetic resin material to be protected and insulated. For example, as disclosed in Patent Document 1, a sheath tube serving as a protective tube is made of a corrugated flexible tube. A water pipe made of a flexible tube made of synthetic resin is inserted into the sheath pipe, and the water pipe is protected by the sheath pipe. Further, a buffer layer made of a foam material having heat retention and buffering properties is integrally molded on the inner circumferential surface of the sheath tube. The buffer layer is made of a soft material such as rubber or soft resin.

Japanese Patent Application Publication No. 10-311462

However, in the protection pipe of the water pipe, it is desired to improve the heat insulation performance of the fluid flowing through the water pipe.
An object of the present invention is to provide a corrugated double pipe and a water pipe device that can improve heat insulation performance.

A corrugated double pipe designed to solve the above problems has a cylindrical inner layer made of a foamed synthetic resin material, and a cylindrical outer layer made of a non-foamed synthetic resin material that is in close contact with the outer peripheral surface of the inner layer. It has a two-layer structure throughout the axial direction, and has annular recesses and annular protrusions alternately provided along the axial direction, or has recesses and protrusions that extend spirally along the axial direction. The present invention is a corrugated double pipe having a striped portion and having concavities and convexities alternately continuous along the axial direction on the inner and outer surfaces, and the foaming ratio of the inner layer is less than 3 times.

A water pipe device for solving the above problems consists of a cylindrical inner layer made of a foamed synthetic resin material, and a cylindrical outer layer made of a non-foamed synthetic resin material and in close contact with the outer peripheral surface of the inner layer. It has a two-layer structure in the entire axial direction, and has annular recesses and annular protrusions alternately provided along the axial direction, or a recessed part and a convex part that extend spirally along the axial direction. and a corrugated double pipe with concavities and convexities continuing alternately along the axial direction on the inner and outer surfaces, and a synthetic resin made of synthetic resin that is inserted into the corrugated double pipe and protected by the corrugated double pipe. The gist is to have a water pipe made of a flexible pipe.

Further, regarding the water pipe device, the foaming ratio of the inner layer is less than 3 times, the corrugated double pipe has flexibility that is easier to roll and deform than the inserted water pipe, and the water pipe is It may be wound while being inserted.

According to the present invention, heat insulation performance can be improved.

FIG. 2 is a perspective view showing the faucet box of the embodiment installed on a pillar. An exploded perspective view showing a faucet box, a water pipe, and a corrugated double pipe. A perspective view showing a corrugated double pipe. A half-sectional view showing a corrugated double pipe. A sectional view showing a state in which a water pipe is inserted into a corrugated double pipe. (a) is a side view showing another example of a corrugated double pipe, and (b) is a sectional view showing another example of a corrugated double pipe. The figure which shows the storage state of the water pipe apparatus.

As shown in FIG. 1 or 2, the water pipe device 10 includes a water pipe P and a corrugated double pipe 50. The water pipe P is made of a flexible pipe made of synthetic resin. The faucet box 11 to which the corrugated double pipe 50 is connected includes a box-shaped box body 13. The box body 13 has an accommodation space 12 that accommodates the fluid pipe fitting 40 .

The box body 13 has a square box shape and includes a front plate part 14, a top plate part 15, a lower plate part 16, and a back plate part 17. The front plate portion 14 is provided with a plurality of outer wall screw insertion holes 14a. A screw (not shown) for fixing to the outer wall board W1 on the front side of the box body 13 is inserted through the outer wall screw insertion hole 14a.

The top plate portion 15 is provided with screw insertion holes 15a for peripheral members, and the lower plate portion 16 and the back plate portion 17 are provided with screw insertion holes for peripheral members (not shown). A screw (not shown) for fixing to the peripheral member on the back side of the box body 13 is inserted through the peripheral member screw insertion hole 15a. A fixing screw insertion hole 15c is provided on the side surface of the top plate portion 15. A screw 18 for fixing the box body 13 to the pillar H is inserted into the fixing screw insertion hole 15c.

The faucet box 11 includes a pipe connection portion 20 on the lower plate portion 16 of the box body 13. The pipe connection part 20 includes a cylindrical connection tube part 21 connected to the lower plate part 16 of the box body 13 via a cap nut 19, a cylindrical connector 22 connected to the connection tube part 21, has. The connector 22 has a plurality of locking protrusions 23 on its inner peripheral surface. The plurality of locking protrusions 23 are provided at intervals in the circumferential direction of the connector 22. When the connecting end of the corrugated double pipe 50 is inserted into the connecting tube 21 and the connector 22, the locking protrusion 23 enters a recess 53 of the corrugated double pipe 50, which will be described later. By fitting the locking protrusion 23 into the recess 53 of the corrugated double pipe 50, the corrugated double pipe 50 is connected to the connecting cylinder part 21 via the connector 22 so as not to slip out.

The faucet box 11 has an opening 26 on the front surface of the front plate portion 14 . The opening 26 allows the second connection port 42 of the fluid pipe fitting 40 accommodated in the housing space 12 of the box body 13 to face the outside of the box body 13 . The faucet box 11 has a joint fixing cylinder part 24 that stands cylindrical from the periphery of the opening 26 in the front plate part 14 . A female thread 24a is formed on the inner circumferential surface of the joint fixing cylindrical portion 24. Further, a male thread 25a provided on the outer peripheral surface of the fixing ring 25 is screwed into the female thread 24a of the joint fixing cylinder portion 24. Then, with the fluid pipe fitting 40 accommodated in the box body 13, the female thread 24a of the joint fixing cylinder part 24 and the male thread 25a of the fixing ring 25 are screwed together, thereby connecting the fixing ring 25 and the box body 13. A part of the fluid pipe fitting 40 is sandwiched between them, and the fluid pipe fitting 40 is fixed to the box body 13.

The fluid pipe fitting 40 is elbow-shaped. The fluid pipe joint 40 includes a cylindrical first connection port 41 at one end along the fluid flow direction, and a cylindrical second connection port 42 at the other end. The first connection port 41 is connected to the water pipe P. A portion of the second connection port 42 protrudes from the wall surface and is connected to a faucet device or the like. A plurality of retaining protrusions 44 are provided on the outer peripheral surface of the first connection port 41 .

A sleeve 49 is fitted onto the first connection port 41 via the water pipe P. Specifically, with the sleeve 49 fitted to the tip of the water pipe P, the sleeve 49 is fitted to the outside of the first connection port 41, and then the sleeve 49 is fitted to the outside of the water pipe P. Press fit. Then, the retaining protrusion 44 bites into the inner peripheral surface of the water pipe P, and the sleeve 49 is press-fitted, thereby connecting the water pipe P to the first connection port 41 of the fluid pipe joint 40.

Next, the corrugated double pipe 50 will be explained.
As shown in FIG. 3 or 4, the corrugated double pipe 50 has annular recesses 53 and annular protrusions 54 alternately provided along the axial direction. Note that the direction in which the central axis L1 of the corrugated double pipe 50 extends is the axial direction of the corrugated double pipe 50, and the direction in which the imaginary line L2 perpendicular to the central axis L1 of the corrugated double pipe 50 extends is the corrugated double pipe. This is the radial direction of the heavy pipe 50. The outer diameter, which is the maximum dimension in the radial direction, of the corrugated double pipe 50 is slightly smaller than the inner diameter of the connecting cylinder portion 21. The corrugated double pipe 50 can be inserted inside the connecting cylinder part 21.

The corrugated double pipe 50 has flexibility that allows it to be more easily rolled and deformed than the water pipe P. In other words, it is easier to bend and deform than the water pipe P. In other words, the water pipe P is less susceptible to winding deformation and has higher rigidity than the corrugated double pipe 50. Therefore, when the water pipe P is bent and deformed, the force with which the water pipe P attempts to return to the shape before bending is greater than that of the corrugated double pipe 50.

The convex portion 54 has a distal end surface 54 a extending in the circumferential direction of the corrugated double pipe 50 . Further, the convex portion 54 has side surfaces 54b extending toward the central axis L1 from each of a pair of peripheral edges extending in the circumferential direction of the distal end surface 54a. In other words, the convex portion 54 includes a tip end surface 54a and a pair of side surfaces 54b. The convex portions 54 adjacent to each other in the axial direction are connected by a bottom surface 53a. Therefore, the recess 53 is defined by a bottom surface 53a and a pair of side surfaces 54b that sandwich the bottom surface 53a in the axial direction.

The locking protrusion 23 provided on the tube connecting portion 20 fits into the recess 53 . The locking projection 23 locks on the outer surface of a convex portion 54 adjacent to the recess 53 into which the locking projection 23 enters. The locking protrusion 23 locks on the side surface 54b of the convex portion 54 facing each other in the axial direction. When the corrugated double pipe 50 is inserted inside the connecting tube 21 and the connector 22 and the locking projection 23 is inserted into the recess 53, the tip 23a of the locking projection 23 is close to the bottom surface 53a of the recess 53. do.

The corrugated double pipe 50 has a two-layer structure including a cylindrical inner layer 51 made of a foamed synthetic resin material, and a cylindrical outer layer 52 made of a non-foamed synthetic resin material and in close contact with the outer peripheral surface of the inner layer 51. It has a shape in which the inner and outer surfaces have concavities and convexities that continue alternately along the axial direction. In other words, the corrugated double pipe 50 is a two-layer pipe configured by overlapping an outer layer 52 on the outer periphery of an inner layer 51 having a cylindrical shape, and is also a corrugated pipe whose cross section along the axial direction has a wave shape. . The inner layer 51 and the outer layer 52 are laminated in the radial direction of the corrugated double pipe 50, and the radial direction of the corrugated double pipe 50 is also the lamination direction of the inner layer 51 and the outer layer 52.

The inner layer 51 is made of low density polyethylene (LD). Low-density polyethylene is a synthetic resin that belongs to crystalline thermoplastic resins in which repeating units of ethylene are bonded with random branches. Moreover, since low density polyethylene is foamed, it has softer properties compared to other polyethylenes.

The outer layer 52 is made of high density polyethylene (HD). High-density polyethylene is a synthetic resin that belongs to crystalline thermoplastic resins in which repeating units of ethylene are bonded in a linear chain with almost no branching. The crystallinity of high density polyethylene is higher than that of low density polyethylene. High density polyethylene is harder than low density polyethylene. The inner layer 51 made of low density polyethylene which is a foamed synthetic resin material is softer than the outer layer 52 which is made of high density polyethylene which is a non-foamed synthetic resin material.

Low-density polyethylene and high-density polyethylene have good electrical insulation properties and chemical resistance such as acid resistance and alkali resistance. Further, low density polyethylene and high density polyethylene have excellent cold resistance and heat insulation properties, and the corrugated double pipe 50 having the inner layer 51 and the outer layer 52 has heat insulation performance.

The inner layer 51 is made of a foamed synthetic resin material, and the outer layer 52 is made of a non-foamed synthetic resin material. The foamed inner layer 51 contains an air layer and has higher heat insulation performance than the non-foamed outer layer 52. Moreover, the foaming ratio of the inner layer 51 is preferably less than 3 times, more preferably less than 2 times. Note that when the foaming ratio of the inner layer 51 is greater than 3 times, the inner layer 51 is likely to be compressed and deformed, and when the water pipe P is inserted into the corrugated double pipe 50, when the tip of the water pipe P comes into contact with it, the inner layer 51 is compressed and deformed. This is because it becomes deformed and easily gets caught, which is undesirable.

In the inner layer 51 and the outer layer 52, if the dimension in the radial direction of the corrugated double pipe 50 is defined as the thickness, the thickness of the outer layer 52 is thinner than the thickness of the inner layer 51. In other words, the thickness of the inner layer 51 is thicker than the thickness of the outer layer 52. The inner layer 51, which has a high heat insulating performance, is made thicker than the outer layer 52, thereby improving the heat insulating performance. Further, by making the thickness of the outer layer 52, which is harder than the inner layer 51, thinner than the inner layer 51, the flexibility of the corrugated double pipe 50 in the bending direction and the winding direction is improved.

Next, the function of the water pipe device 10 will be explained together with the piping method of the water pipe P.
First, screws inserted into the outer wall screw insertion holes 14a of the box body 13 are fixed to the back surface of the outer wall board W1, and the box main body 13 is fixed to the back surface of the outer wall board W1. Note that a wall hole Wa is formed in the outer wall plate W1, and the joint fixing cylinder portion 24 of the faucet box 11 faces the front side of the outer wall plate W1 from this wall hole Wa.

Next, on the back side of the outer wall board W1, insert the connecting end of the corrugated double pipe 50 inside the connector 22 of the pipe connection part 20 of the faucet box 11, and then insert the connecting end of the corrugated double pipe 50 into the corrugated double pipe. It is inserted into the recess 53 of the heavy pipe 50. Then, the locking projection 23 locks onto the outer surface of the convex portion 54 adjacent to the recess 53 into which the locking projection 23 is inserted, and the corrugated double pipe 50 is connected to the pipe connection portion 20 . That is, the corrugated double pipe 50 with improved heat insulation performance is connected to the faucet box 11.

Next, the water pipe P is inserted into the corrugated double pipe 50 from the end opposite to the end connected to the faucet box 11 in the corrugated double pipe 50, and the water pipe P is inserted into the faucet box 11. Push towards.
As shown in FIG. 5, the water pipe P moves along the inner layer 51 that constitutes the inner peripheral surface of the corrugated double pipe 50. Since the inner layer 51 has a low foaming ratio, the water pipe P moves while sliding on the inner peripheral surface of the corrugated double pipe 50 due to the inner layer 51.

After the tip of the water pipe P is inserted into the box body 13, the water pipe P is pulled out to the front side of the outer wall plate W1 through the opening 26 of the box body 13 on the front side of the outer wall plate W1. The end of the water pipe P pulled out to the front side of the outer wall board W1 is connected to the first connection port 41 of the fluid pipe joint 40. Thereafter, the water pipe P pulled out to the front side of the outer wall plate W1 is returned into the box body 13, and the male thread 25a of the fixing ring 25 is screwed into the female thread 24a of the joint fixing cylinder part 24 of the box body 13. Then, the fluid pipe joint 40 is fixed to the box main body 13 and the fluid pipe joint 40 is accommodated within the box main body 13. As a result, the end of the water pipe P is also accommodated within the box body 13. The water pipe P is protected at its connection end side to the fluid pipe joint 40 by the faucet box 11, and the other part is protected by the corrugated double pipe 50 having heat insulating performance. The fluid flowing through the water pipe P is insulated by the corrugated double pipe 50.

According to the above embodiment, the following effects can be obtained.
(1) The outer layer 52 of the corrugated double pipe 50 is made of high-density polyethylene, while the inner layer 51 is made of foamed low-density polyethylene. Therefore, the water pipe P is protected by the corrugated double pipe 50 with improved heat insulation performance, and the heat insulation performance of the fluid flowing through the water pipe P is improved.

(2) The inner layer 51 is made of foamed low-density polyethylene, and in this embodiment, the foaming ratio of the inner layer 51 is set to a value that makes it difficult for the inner layer 51 to be compressed and deformed. Therefore, when the water pipe P is inserted into the corrugated double pipe 50, even if the tip of the water pipe P comes into contact with the inner peripheral surface of the corrugated double pipe 50, the inner layer 51 constituting the inner peripheral surface is compressively deformed. is suppressed. Therefore, the tip of the water pipe P is less likely to get caught on the inner circumferential surface of the corrugated double pipe 50, and the workability of piping the water pipe P can be improved.

(3) The inner layer 51 of the corrugated double pipe 50 has a small foaming ratio of less than 3 times. By setting such a foaming ratio, the inner layer 51 can be made difficult to be compressed and deformed, and when the water pipe P is inserted into the corrugated double pipe 50, the tip of the water pipe P reaches the inner periphery of the corrugated double pipe 50. Even when the inner layer 51 makes contact with the surface, compressive deformation of the inner layer 51 constituting the inner circumferential surface is further suppressed.

(4) The water pipe P has higher rigidity than the corrugated double pipe 50 and is difficult to wind. Therefore, if a bend is formed in the corrugated double pipe 50 connected to the faucet box 11, the water pipe P is pressed against the inner layer 51 of the corrugated double pipe 50 inside the corrugated double pipe 50. A place is formed. However, since the foaming ratio of the inner layer 51 is set to less than 3 times and the foaming ratio of the inner layer 51 is set to a value that makes it difficult to compress and deform, crushing marks are formed in the corrugated double pipe 50 where the water pipe P comes into pressure contact. can be suppressed. As a result, it is possible to suppress the inner layer 51 of the corrugated double pipe 50 from being crushed and the heat insulation performance from decreasing.

(5) The corrugated double pipe 50 has high heat insulation performance by making the inner layer 51, which has high heat insulation performance, thicker than the outer layer 52. Furthermore, by making the thickness of the outer layer 52, which is harder than the inner layer 51, thinner than the thickness of the inner layer 51, the flexibility of the corrugated double tube 50 in the bending direction and the winding direction is improved, and the corrugated double tube 50 It is easier to wind.

This embodiment can be modified and implemented as follows. This embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.
○ As shown in FIGS. 6(a) and 6(b), the corrugated double pipe 60 has a concave portion 61 and a convex portion 62 extending spirally along the axial direction, and has an inner surface and a convex portion 62. The outer surface may have a shape in which concavities and convexities are alternately continuous along the axial direction. The grooved portion 61 and the convex portion 62 extend continuously in a spiral along the circumferential direction of the corrugated double pipe 50 from one end of the corrugated double pipe 60 to the other end in the axial direction. In the corrugated double pipe 60, a concave portion 61 is formed between axially adjacent convex portions 62. The concave portion 61 and the convex portion 62 extend without intersecting each other.

The corrugated double pipe 60 has a cylindrical inner layer 63 made of a foamed synthetic resin material, and a cylindrical outer layer 64 made of a non-foamed synthetic resin material that is in close contact with the outer peripheral surface of the inner layer 63. It has a layered structure throughout the axial direction. The corrugated double pipe 60 is a corrugated pipe whose cross section along the axial direction has a corrugated shape. The inner layer 63 is made of low density polyethylene, and the outer layer 64 is made of high density polyethylene. The water pipe device 10 is constituted by the corrugated double pipe 60 and the water pipe P.

○ As shown in FIG. 7, the water pipe device 10 consisting of the corrugated double pipe 50 and the water pipe P is stored in a state in which the water pipe P is inserted into the corrugated double pipe 50 and wound. It may be a state. The water pipe device 10 is manufactured in a factory by inserting the water pipe P into the corrugated double pipe 50, and by winding the corrugated double pipe 50, the water pipe P with the corrugated double pipe 50 is manufactured. P is also wound.

The water pipe P has higher rigidity than the corrugated double pipe 50 and is difficult to wind. Therefore, when the corrugated double pipe 50 is wound together with the water pipe P, a portion is formed inside the corrugated double pipe 50 where the water pipe P comes into pressure contact with the inner layer 51 of the corrugated double pipe 50. Ru. However, since the foaming ratio of the inner layer 51 is less than 3 times and the foaming ratio is set to a value that makes it difficult to compress and deform, crushing marks are formed in the corrugated double pipe 50 where the water pipe P comes into pressure contact. can be suppressed. As a result, collapse of the inner layer 51 of the corrugated double pipe 50 can be prevented from deteriorating the heat insulation performance.

○ The foaming ratio of the inner layers 51 and 63 may be 3 times or more.
In the embodiment, the corrugated double pipes 50 and 60 are used as protective pipes for the water pipe P, but the corrugated double pipes 50 and 60 may also be protective pipes that protect wiring such as cables. In this case, the corrugated double pipes 50 and 60 are connected to a wiring box or a power distribution box. Further, the corrugated double pipes 50 and 60 may serve as protectors for protecting fluid pipes through which refrigerant of the air conditioner flows.

○ The inner layers 51 and 63 of the corrugated double pipes 50 and 60 were formed from low density polyethylene, and the outer layers 52 and 64 were formed from high density polyethylene, but the materials of the inner layers 51 and 63 and the outer layers 52 and 64 were, for example, The foamed synthetic resin material may be changed to, for example, ethylene-vinyl acetate copolymer resin (EVA) or urethane as appropriate.

The technical ideas that can be understood from the above embodiment and modification examples will be described.
(1) The outer layer of the corrugated double pipe is made of high-density polyethylene.
(2) The inner layer of the corrugated double pipe is made of low density polyethylene.

P... Water pipe, 10... Water pipe device, 50, 60... Corrugated double pipe, 51, 63... Inner layer, 52, 64... Outer layer, 53... Recessed part, 54... Convex part, 61... Recessed part, 62... convex part,

Claims (2)

It has a two-layer structure in the entire axial direction, consisting of a cylindrical inner layer made of a foamed synthetic resin material and a cylindrical outer layer made of a non-foamed synthetic resin material that is in close contact with the outer peripheral surface of the inner layer,
It has annular recesses and annular protrusions alternately provided along the axial direction, or it has a recessed part and a convex part that extend spirally along the axial direction, and the inner and outer surfaces are provided with an axially extending part. A corrugated double pipe with concavities and convexities that alternate along the
a water pipe made of a flexible pipe made of synthetic resin that is inserted into the corrugated double pipe and protected by the corrugated double pipe;
The corrugated double pipe has flexibility that allows it to be more easily rolled and deformed than the inserted water pipe,
The water pipe device wherein the inner layer has a foaming ratio of less than 3 times . The water pipe device according to claim 1, wherein the corrugated double pipe is wound with the water pipe inserted therethrough.