JP2011208686A - Flexible synthetic resin pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible synthetic resin pipe for smoothly holding the winding structure of a pipe body while preventing the separation of a first engaging portion side protruded strip from the confronting face of a second engaging portion side protruded strip on the outer periphery side of the pipe body when curved.SOLUTION: The flexible synthetic resin pipe includes the pipe body 11 formed by spirally winding a strip 15 having a first engaging portion 13 formed on one side in the axial direction and a second engaging portion 14 formed on the other side in the axial direction while spirally winding the first engaging portion 13 engaging with the second engaging portion 14 from the outside in the radial direction of the pipe body 11. On both engaging portions 13, 14, the first and second engaging portion side protruded strips 173, 183 are provided, respectively, which are protruded confronting each other in the axial direction of the pipe body 11 and which abut on each other on the outer periphery side of the pipe body 11 when curved. The confronting face 183a of the second engaging portion side protruded strip 183 is gradually inclined to the orthogonal face orthogonal thereto in the axial direction of the pipe body 11 as tending toward the front end side to come closer to the first engaging portion side protruded strip 173.

Description

  The present invention relates to a flexible synthetic resin tube used as a protective tube for, for example, an electric wire, a power cable, or a communication cable buried in the ground.

  For example, as a flexible synthetic resin tube used as a protective tube for electric wires, power cables, communication cables, etc. buried in the ground, as shown in FIG. 30, the first engaging portion along one side in the axial direction A belt-like body 200 made of a hard synthetic resin such as a hard vinyl chloride resin having 210 formed therein and a second engagement portion 220 formed along the other side in the axial direction as a connection with the first engagement portion is spiral. The first engagement portion 210 and the second engagement portion 220 adjacent to the first engagement portion 210 are engaged with each other in a non-adhered state so as to be slidable in the axial direction. There has already been proposed a flexible synthetic resin tube 100 having a tube body 110 formed by attaching an inner layer material 120 made of a soft synthetic resin along the inner peripheral surface of the tube body 110 (patent). Reference 1).

That is, the flexible synthetic resin tube 100 is excellent in flexibility because the inner layer material 120 is formed of a soft synthetic resin.
On the other hand, since the tube body 110 is formed of a hard synthetic resin, it is excellent in strength, and the first engagement portion 210 and the second engagement portion 220 are slidable in the axial direction. Therefore, when the tube main body 110 is bent, the first engagement portion 210 and the second engagement portion 220 slide in a direction away from each other on the outer peripheral side of the tube main body 110 when it is bent. On the other hand, on the inner peripheral side, the first engaging portion 210 and the second engaging portion 220 slide in the approaching direction, and the tube main body 110 substantially follows the bending of the inner layer material 120. In this case, the first engaging portion 210 is engaged with the second engaging portion 220 adjacent thereto from the outside in the radial direction of the tube main body 110.

Japanese Patent Laid-Open No. 9-229247

By the way, the engaging portions 210 and 220 of the flexible synthetic resin tube 100 are provided with protrusions 211 and 221 protruding so as to face each other in the axial direction of the tube main body 110, and this protrusion 211 , 221 slide in the axial direction in the engaging portions 210, 220 on the outer peripheral side when the tube body 110 is bent, and come into contact with each other. That is, when the tube main body 110 is bent, on the outer peripheral side, the first engaging portion 210 and the second engaging portion 220 slide in a direction away from each other, and the protrusions 211 and 221 contact each other.
In that case, depending on the degree of bending when the tube main body 110 is bent, the radius of the tube main body 110 is changed along the opposite surface 221a of the protrusion 221 of the second engagement portion 220. May move out of direction. At this time, when the protrusion 211 of the first engagement portion 210 moves outward in the radial direction of the pipe main body 110 and separates from the facing surface 221 a of the protrusion 221 of the second engagement portion 220, both engagement portions 210 are formed. , 220 is released, and the winding structure of the tube body 110 cannot be maintained.

  The present invention has been made in view of such points, and the object of the present invention is to provide a first from the opposite surface of the protrusion of the second engaging portion on the outer peripheral side when the tube body is curved. An object of the present invention is to provide a flexible synthetic resin tube that can prevent the protrusion of the engaging portion from being detached and can smoothly hold the winding structure of the tube body.

In order to achieve the above object, according to the solution provided by the present invention, the first engaging portion is formed along one side in the axial direction and made of synthetic resin, and connected to the first engaging portion in the axial direction. A belt-like body in which a second engagement portion is formed along the other side is spirally wound, and the first engagement portion and a second engagement portion adjacent thereto are slidable in the axial direction. It is possible to have a tube body which is engaged in a non-adhered state and wound in a spiral shape so that an inner layer material made of a soft synthetic resin is attached along the inner peripheral surface of the tube body. A flexible synthetic resin pipe is assumed. Further, the first engaging portion engages with the second engaging portion adjacent thereto from the radially outer side of the tube body, that is, from the radially outer side of the tube body toward the radially inner side. In addition, there are protrusions that project from both engaging portions so as to face each other in the axial direction of the tube main body, and slide and contact each other in the axial direction when the tube main body is curved. Each is provided. And the opposing surface of the protrusion of the said 2nd engagement part is inclined so that it may approach the protrusion of the said 1st engagement part as it becomes the front end side of the protrusion.
Due to this specific matter, the opposite surface of the protrusion of the second engagement portion is inclined so as to approach the protrusion of the first engagement portion as it comes to the tip side of the protrusion, so that the pipe body is bent. The protrusion of the first engagement portion that comes into contact with the protrusion of the second engagement portion on the outer peripheral side of the second engagement portion becomes closer to the distal end side of the protrusion of the second engagement portion. The protrusion on the opposite surface of the protrusion becomes stronger and it becomes difficult to move outward in the radial direction of the pipe body. As a result, when the tube body is bent, the protrusion of the first engagement portion from the opposing surface of the protrusion of the second engagement portion on the outer peripheral side is prevented, and the winding structure of the tube body is smoothed. It is possible to hold it.
Moreover, when a large axial force acts on the pipe body due to ground fluctuations such as an earthquake, and the pipe body extends, the protrusions of the first engaging portion protrude toward the tip side. It is strongly abutted against the opposing surface of the ridge of the second engaging portion that is inclined in the direction of strengthening, that is, the tip side is inclined so as to be closer to the ridge of the first engaging portion. At this time, even if the tip of the protrusion of the second engagement portion is bent toward the opposite protrusion of the first engagement portion by the contact of the protrusion of the first engagement portion, the tip side is a protrusion of the first engagement portion. The abutment of the second engaging portion that is inclined toward the ridge is brought into contact with the opposite surface of the ridge, so that the ridge of the first engaging portion can be held without overriding the ridge of the second engaging portion in the axial direction. . Thereby, even if the pipe body is extended due to ground fluctuation such as an earthquake, the winding structure of the pipe body can be held smoothly.

Moreover, it is preferable to incline the opposing surface of the ridge of the first engaging portion so as to approach the ridge of the second engaging portion in the axial direction of the pipe body as it becomes the tip side of the ridge. .
In this case, since the opposing surface of the protrusion of the first engaging portion is inclined so as to approach the protrusion of the second engaging portion as it comes to the tip side of the protrusion, the tube body is bent. The protrusion of the first engagement portion that comes into contact with the protrusion of the second engagement portion on the outer peripheral side of the second engagement portion becomes closer to the distal end side of the protrusion of the second engagement portion. The protrusion on the opposite surface of the ridge becomes stronger and it becomes more difficult to move outward in the radial direction of the pipe body. As a result, when the tube body is bent, the protrusion of the first engagement portion from the opposing surface of the protrusion of the second engagement portion on the outer peripheral side thereof is further prevented, and the winding structure of the tube body is reduced. It can be held more smoothly.
In addition, when a large axial force acts on the pipe body due to ground fluctuations such as an earthquake and the pipe body extends, the first engaging portion is inclined in the direction in which the hook becomes stronger as it becomes the tip side, that is, the tip side is the first engaging portion. The opposing surface of the ridge of the first engaging portion inclined so as to be closer to the ridge of the second engaging portion is inclined so that the tip side is closer to the ridge of the first engaging portion. Strongly abuts against the opposite surface of the ridge. At this time, due to the abutment of the protrusions of both engaging portions, the tip of the protrusion of the first engagement portion is opposite to the protrusion of the second engagement portion, and the tip of the protrusion of the second engagement portion is Even if each of the first engaging portions bends to the opposite side of the ridge, the tip side of the first engaging portion is inclined toward the ridge of the second engaging portion. The ridge of the first engagement portion rides over the ridge of the second engagement portion in the axial direction due to the contact with the opposite surface of the ridge of the second engagement portion that is inclined toward the ridge of the portion. It can be endured smoothly. Thereby, even if a pipe body is extended by ground changes, such as an earthquake, the winding structure of a pipe body can be held more smoothly.

Further, the protrusions projecting in the axial direction from the tip portions of the opposing surfaces of the protrusions of the both engaging portions, and engaging the protrusions from the inner and outer diameter directions when the protrusions are in contact with each other. A piece may be provided.
In this case, since the protrusions of both engaging portions are engaged with each other by the engaging pieces from the inner and outer diameter directions, the protrusion of the second engaging portion is formed on the outer peripheral side when the tube body is bent. The protrusion of the first engaging portion that is in contact with the stripe engages with the engagement piece of the protrusion of the second engaging portion along the opposite surface of the protrusion of the second engaging portion. This prevents the pipe body from moving radially outward. Accordingly, when the tube body is bent, the protrusion of the first engagement portion from the facing surface of the protrusion of the second engagement portion on the outer peripheral side is reliably prevented, and the winding structure of the tube body is prevented. Can be effectively retained.
Moreover, when a large axial force acts on the pipe body due to ground fluctuations such as an earthquake, the pipe body extends, and the opposite surface of the protrusion of the first engagement portion is the first engagement portion on the tip side. It strongly abuts against the opposing surface of the ridge of the second engaging portion inclined so as to be closer to the ridge. At this time, due to the abutment of the protrusions of both engaging portions, the tip of the protrusion of the first engagement portion is opposite to the protrusion of the second engagement portion, and the tip of the protrusion of the second engagement portion is Even if each of the first engaging portions bends to the opposite side of the protrusions, the protrusions of the first engaging portions are engaged with the protrusions of the second engaging portions by the engagement of the engaging pieces of the protrusions of both engaging portions. Can endure without having to get over the axis. Thereby, even if a pipe main body expands by ground changes, such as an earthquake, the winding structure of a pipe main body can be held reliably.

  Further, the protrusion of the second engagement portion may be formed thicker in the axial direction of the tube body than the protrusion of the first engagement portion. In this case, the first engaging portion can be supported from the inside by the thick protrusion of the second engaging portion, and the flatness of the tube body can be effectively prevented.

Further, the protrusion of the second engagement portion may be provided with a recess opening toward the tip thereof and a plurality of protrusions divided by the recess in the axial direction of the tube main body.
In this case, since the thick protrusion of the second engaging portion is divided into a plurality of protrusions in the axial direction of the tube main body by the recess, the first protrusion is formed by the divided protrusions. The engaging portion is uniformly supported from the inside, and the flatness of the tube body can be efficiently prevented. In addition, the material of the thick protrusion is reduced by the recess, and the cost of the flexible synthetic resin tube (tube body) can be reduced.

Further, when the tube main body is bent, the inner surfaces of the tube main body come into contact with each other on the opposite side surfaces of the protrusions of the first engaging portion, and the second engaging portion adjacent to the first engaging portion. At least one of the vertical surfaces may be inclined so as to form a space between the both surfaces that gradually increases in the axial direction of the tube main body toward the proximal end side of the protrusion of the first engaging portion.
In this case, at least one of the opposite flange surface of the protrusion of the first engagement portion and the vertical surface of the second engagement portion adjacent to the first engagement portion is the first engagement between both surfaces. Since it is inclined so as to form a space that gradually increases in the axial direction of the tube body as it becomes the proximal end side of the protrusion of the joint portion, when the tube body is curved, the both surfaces are on the inner peripheral side thereof It abuts so as to close the space. For this reason, when a communication cable such as an optical fiber cable in which an allowable bending radius (for example, about 0.3 mR) is accommodated inside the flexible synthetic resin tube, when the tube body is bent, Further bending is regulated by bringing the two surfaces into contact with each other on the inner peripheral side. Thereby, the malfunction by the disconnection etc. of a communication cable can be prevented reliably.

In order to achieve the above object, according to another solution provided by the present invention, the first engagement portion is formed along one side in the axial direction and is connected to the first engagement portion. A belt-like body having a second engagement portion formed along the other side in the axial direction is spirally wound, and the first engagement portion and the second engagement portion adjacent thereto are axially connected to each other. The pipe body is formed by being wound in a non-adhered state so as to be slidable and spirally wound, and an inner layer material made of a soft synthetic resin is attached along the inner peripheral surface of the pipe body. The same applies to the attached flexible synthetic resin tube. Further, the first engaging portion is engaged with the second engaging portion adjacent thereto from the radially outer side of the tube main body, and both the engaging portions are engaged with each other in the axial direction of the tube main body. Projections are provided so as to be opposed to each other, and when the tube body is bent, the projections slide and contact each other in the axial direction. Then, the protrusions of both the engaging portions are protruded in the axial direction from the tip portions of the opposing surfaces, and the protrusions are engaged with each other from the inner and outer diameter directions when the protrusions are in contact with each other. An engagement piece is provided.
Due to this specific matter, the protrusions of the two engaging portions are engaged with each other by the engaging pieces from the inner and outer diameter directions. Therefore, when the tube main body is bent, the protrusions of the second engaging portion on the outer peripheral side thereof. The protrusion of the first engagement portion that is in contact with the engagement portion of the protrusion engages with the engagement piece of the protrusion of the second engagement portion, along the opposite surface of the protrusion of the second engagement portion. It is prevented that the pipe body moves outward in the radial direction. Accordingly, when the tube body is bent, the protrusion of the first engagement portion from the facing surface of the protrusion of the second engagement portion on the outer peripheral side is reliably prevented, and the winding structure of the tube body is prevented. Can be effectively retained.

  In short, in short, the opposing surfaces of the ridges of the second engaging portion are inclined so as to approach the ridges of the first engaging portion as they become the tip side of the ridges, or the ridges of both engaging portions are By engaging with each other from the inner and outer diameter directions by the engagement pieces, when the tube body is bent, the tube body radially outwards with respect to the opposing surface of the protrusion of the second engagement portion on the outer peripheral side. It is difficult to move the ridge of the first engaging portion, and the detachment of the ridge of the first engaging portion from the facing surface of the ridge of the second engaging portion is prevented. It can be held smoothly. In addition, when the pipe body is extended due to ground fluctuation such as an earthquake, the opposing surface of the first engaging portion protrudes strongly against the opposing surface of the second engaging portion, and the second engaging portion Even if the tip of the ridge is bent toward the opposite ridge of the first engagement portion, the tip of the ridge is in contact with the opposite surface of the ridge of the second engagement portion inclined toward the ridge of the first engagement portion. By contact, the protrusion of the first engagement portion can be held without overriding the protrusion of the second engagement portion in the axial direction, and the winding structure of the tube body can be smoothly held.

It is a layout figure of the flexible synthetic resin pipe | tube which concerns on the 1st Embodiment of this invention. It is sectional drawing which cut | disconnected the linear part of the flexible synthetic resin pipe | tube of FIG. 1 along the pipe axis. It is the A section enlarged view of FIG. It is sectional drawing which cut | disconnected the curved part of the flexible synthetic resin pipe | tube of FIG. 1 along the pipe axis. It is the B section enlarged view of FIG. It is the C section enlarged view of FIG. It is sectional drawing which cut | disconnected the coupling of FIG. 1 along the pipe axis. It is sectional drawing which cut | disconnected the joint part of the flexible synthetic resin pipe | tube of FIG. 1 along the pipe axis with the joint. Sliding test inside flexible plastic tube It is a partially expanded view which expands and shows the cross section which notched the linear part of the flexible synthetic resin pipe | tube which concerns on the modification of 1st Embodiment along the pipe axis. It is sectional drawing which cut | disconnected the linear part of the flexible synthetic resin pipe | tube which concerns on the 2nd Embodiment of this invention along the pipe axis. It is the D section enlarged view of FIG. It is sectional drawing which cut | disconnected the curved part of the flexible synthetic resin pipe | tube which concerns on the 2nd Embodiment of this invention along the pipe axis. It is the E section enlarged view of FIG. It is the F section enlarged view of FIG. It is a partially expanded view which expands and shows the cross section which notched the linear part of the flexible synthetic resin pipe | tube which concerns on the modification of 2nd Embodiment along the pipe axis. It is the partially expanded view which expands and shows the cross section which notched the outer peripheral side of the curved part of the flexible synthetic resin pipe | tube along the pipe axis similarly. It is a partially expanded view which expands and shows the cross section which notched the linear part of the flexible synthetic resin pipe | tube which concerns on the other modification of 2nd Embodiment along the pipe axis. It is the partially expanded view which expands and shows the cross section which notched the outer peripheral side of the curved part of the flexible synthetic resin pipe | tube along the pipe axis similarly. It is sectional drawing which cut | disconnected the linear part of the flexible synthetic resin pipe | tube which concerns on the 3rd Embodiment of this invention along the pipe axis. It is the G section enlarged view of FIG. It is sectional drawing which cut | disconnected the curved part of the flexible synthetic resin pipe | tube which concerns on the 3rd Embodiment of this invention along the pipe axis. It is the H section enlarged view of FIG. It is the I section enlarged view of FIG. It is a partially expanded view which expands and shows the cross section which notched the linear part of the flexible synthetic resin pipe | tube which concerns on the modification of 3rd Embodiment along the pipe axis. It is the partially expanded view which expands and shows the cross section which notched the outer peripheral side of the curved part of the flexible synthetic resin pipe | tube along the pipe axis similarly. It is the partially expanded view which expands and shows the cross section which similarly cut out the inner peripheral side of the curved part of a flexible synthetic resin pipe | tube along a pipe axis. It is the partially expanded view which expands and shows the cross section which notched the linear part of the flexible synthetic resin pipe | tube which concerns on the 4th Embodiment of this invention along the pipe axis. It is a partially expanded view which expands and shows the cross section which notched the linear part of the flexible synthetic resin pipe | tube which concerns on the modification of 4th Embodiment along the pipe axis. It is sectional drawing which shows a part of flexible synthetic resin pipe | tube which concerns on a prior art example.

  Embodiments of the present invention will be described below with reference to the accompanying drawings for understanding of the present invention. In addition, the following embodiment is an example which actualized this invention, Comprising: The thing of the character which limits the technical scope of this invention is not.

  In FIG. 1, 1 shows the flexible synthetic resin pipe | tube which concerns on the 1st Embodiment of this invention, and this flexible synthetic resin pipe | tube 1 was derived | led-out from main pipes X, such as a supply system and a drawing-in system. It serves to protect the fiber optic cable (not shown) at the curved site. In other words, the flexible synthetic resin tube 1 is used each time the optical fiber cable is bent in a desired direction (only two locations are shown in FIG. 1), and a plurality of straight polyvinyl chloride resins that protect the straight portion of the optical fiber cable are used. Combined with tubes 21 and 21 (only two are shown in FIG. 1). Specifically, the flexible synthetic resin pipe 1 has one end (left end in FIG. 1) connected to the branch pipe X1 attached to the body pipe X via a joint 22 and the other end (see FIG. 1 is connected to one end of the straight pipe 21 (the left end in FIG. 1) via a joint 22. In addition, one end (left end in FIG. 1) of another flexible synthetic resin pipe 1 having the same configuration is connected to the other end (right end in FIG. 1) of the straight pipe 21 via a joint 22, The other end (lower end in FIG. 1) of the flexible synthetic resin tube 1 is connected to one end (upper end in FIG. 1) of another straight pipe 21 having the same configuration via a joint 22.

As shown in FIGS. 2 and 3, each flexible synthetic resin tube 1 includes a tube body 11 and an inner layer material 12.
The tube body 11 is made of hard polyvinyl chloride resin, and includes a first engagement portion 13 along one side in the axial direction (left side in FIGS. 2 and 3) and is connected to the first engagement portion 13. A belt-like body 15 having a second engagement portion 14 is spirally wound along the other side in the axial direction (the right side in FIGS. 2 and 3) as a shape, and is adjacent to the first engagement portion 13. The second engaging portion 14 is formed by being wound in a non-adhered state and spirally wound so as to be slidable in the axial direction. The belt-like body 15 is obtained by injection molding of a hard vinyl chloride resin, one side (the left side in FIGS. 2 and 3) sandwiching the vertical wall part 16 is the first engaging part main body 17 and the other side (FIG. 2). And the right side in FIG. 3 is the second engaging portion main body 18. In this case, the first engaging portion main body 17 (first engaging portion 13) is radially outward of the tube main body 11 with respect to the second engaging portion main body 18 (second engaging portion 14) adjacent thereto. Is engaged radially inward.

The second engagement portion main body 18 includes an inner wall portion 181 and a second engagement portion side protrusion 183 (protrusion).
The inner wall portion 181 extends in one direction (rightward in FIG. 3) from the inner end of the vertical wall portion 16 (radially inner end of the pipe body 11) so as to be orthogonal to the vertical wall portion 16. In addition, the inner wall of the tube body 11 is formed. Further, the second engaging portion side protrusion 183 protrudes radially outward (upward in FIG. 3) from the distal end portion (right end portion in FIG. 3) of the inner wall portion 181. .

The first engagement portion main body 17 includes an outer wall portion 171 and a first engagement portion side protrusion 173 (protrusion).
The outer wall portion 171 has an opposite side direction opposite to the inner wall portion 181 so as to be orthogonal to the vertical wall portion 16 from the outer end of the vertical wall portion 16 (the radially outer end of the pipe body 11). 3 (to the left in FIG. 3), the outer wall of the tube body 11 is formed. The first engaging portion side protrusion 173 protrudes radially inward (downward in FIG. 3) of the pipe body 11 from the tip (left end in FIG. 3) of the outer wall portion 171. As shown in FIGS. 4 to 6, the first engaging portion side protrusion 173 and the second engaging portion side protrusion 183 are opposed to each other in the axial direction of the pipe body 11. The first engaging portion side protrusion 173 and the second engaging portion side protrusion 183 slide in the axial direction of the tube main body 11 on the outer peripheral side when the tube main body 11 is bent. The opposing surfaces 173a and 183a can be brought into contact with each other.

The distal end of the second engaging portion side protrusion 183 is slidably contacted with the inner side surface (lower side surface in FIG. 3) of the outer wall portion 171 of the first engaging portion main body 17 in the axial direction of the tube main body 11. ing. On the other hand, the tip of the first engaging portion side protrusion 173 is slidable in the axial direction of the tube main body 11 with respect to the outer side surface (upper side surface in FIG. 3) of the inner wall portion 181 of the second engaging portion main body 18. Is in contact with The second engaging portion side protrusion 183 is formed thicker in the axial direction of the tube body 11 than the first engaging portion side protrusion 173, and opens toward the tip (upward in FIG. 3). The first ridge portion 184 and the second ridge portion 185 are divided into two in the axial direction of the tube main body 11 with the recessed portion 180 formed.
In this case, the tips of the first protrusion 184 and the second protrusion 185 are in sliding contact with the inner side surface of the outer wall 171 of the first engaging portion main body 17. Moreover, the 1st protrusion part 184 is located in the 1st engagement part side protrusion 173 side (left side in FIG. 3), and the surface of the 1st engagement part side protrusion 173 side is the 2nd engagement part side. It is the opposite surface 183a of the protrusion 183.

Here, the impact resistance strength of the tube body 11 will be described.
As an evaluation method of impact resistance required for the flexible synthetic resin tube 1 that accommodates a communication cable such as an optical fiber cable, there is a test method defined in the Electric Wire Joint Groove Test Implementation Manual (Draft). This is because a weight calculated by multiplying the weight (kg) of the material of the tube main body 11 by a coefficient “3.246” is used as the drop height (cm), and a weight of 15 kg at the tip is dropped. This is to confirm the presence or absence of cracks. At this time, the assumed use length of the flexible synthetic resin tube 1 is about 2 m, and when the weight of the joint 22 is added to this, the weight is about 4.5 kg. If it is calculated, it will be about 15 cm.
When the same flexible synthetic resin tube is manufactured with normal hard vinyl chloride resin (equivalent material to VP tube), if the above 15 kg weight is dropped from this height, cracking occurs and this level of impact resistance In terms of strength, there is anxiety about use when buried under the road. For this reason, by using an impact-resistant hard vinyl chloride resin, cracks and the like do not occur even in the above-described impact resistance test.
The material of the tube body 11 (strip 15) used in the present invention is a vinyl chloride resin composition containing an impact resistance modifier. The total amount of the modifier is in the range of 2 to 15 phr with respect to the vinyl chloride resin 100. If it is less than 2 phr, the impact resistance is poor, and if it exceeds 15 phr, the moldability becomes difficult.
Examples of the modifier used in the present invention include acrylic rubber, methyl methacrylate-butadiene-styrene copolymer rubber (MBS), acrylonitrile-butadiene copolymer rubber, and chlorinated polyethylene. In addition, the modifier used by this invention may be one of these, or a combination of two or more.

  The first ridge portion 184 is inclined so as to approach the first engagement portion-side ridge 173 with respect to an orthogonal plane orthogonal to the axial direction of the tube main body 11 as it comes to the distal end side. Thereby, the facing surface 183a is similarly inclined. Further, the second ridge portion 185 is inclined so as to approach the outer end of the vertical wall portion 16 with respect to an orthogonal plane orthogonal to the axial direction of the tube main body 11 as it comes to the tip side. In this case, the second engaging portion side ridge 183 is the first ridge portion 184 and the second ridge portion 185, and has a substantially V cross-section that opens outward so as to be separated toward the tip side. Shaped in a letter shape.

  Further, the facing surface 173a of the first engaging portion side ridge 173 is in the axial direction of the tube body 11 as the tip surface side of the first engaging portion side ridge 173 becomes perpendicular to the orthogonal surface. It inclines so that it may approach the 1st protrusion part 184 of the 2nd engaging part side protrusion 183. As shown in FIG.

  Further, as shown in FIGS. 7 and 8, the joint 22 has one end (left end in FIGS. 7 and 8) connected to the straight pipe 21 or the branch pipe X1, and the other end (right end in FIGS. 7 and 8). ) Has an insertion portion 221 through which the end of the flexible synthetic resin tube 1 (tube body 11) is inserted. Inside the insertion portion 221, a joint inner core 223 is integrally formed along the inner peripheral surface of the tube main body 11, that is, the inner wall portion 181 of the second engagement portion main body 18 when the tube main body 11 is inserted. It is provided and connected in a watertight state by a bonding agent or an adhesive filled so as to fill a gap between the joint inner core 223 and the inner layer material 12. In addition, a female screw portion 222 is provided on the inner peripheral surface of the insertion portion 221. An end of the straight portion of the flexible synthetic resin tube 1, that is, the outer wall portion 171 of the first engaging portion main body 17 in the straight portion is screwed to the female screw portion 222 via an adhesive (not shown). Yes. In this case, the female threaded portion 222 of the insertion portion 221 includes an outer end of the vertical wall portion 16 in the straight portion of the flexible synthetic resin tube 1 and an outer end of the first engaging portion side protrusion 173 adjacent thereto. The interval between is almost the same.

Also, the first flange of the vertical wall 16 as the vertical surface of the second engaging portion 14 adjacent to the opposite flange surface 173b of the first engaging portion side protrusion 173 and the first engaging portion side protrusion 173 is provided. The engagement portion side surface 16a (the right side surface in FIG. 6) comes into contact with each other on the inner peripheral side when the tube body 11 is bent. The opposite flange surface 173b of the first engaging portion side protrusion 173 is between the first engaging portion side surface 16a of the vertical wall portion 16 and the base end side of the first engaging portion side protrusion 173. As shown in FIG. 6, the tube body 11 is inclined so as to form a space (not shown) that gradually increases in the axial direction of the tube body 11.
In this case, when the tube main body 11 is bent, the first engagement portion side surface 16a of the vertical wall portion 16 and the opposite flange surface 173b of the first engagement portion side protrusion 173 are formed between the both surfaces on the inner peripheral side. Abutting to close the space, the allowable bending radius on the inner peripheral side of the flexible synthetic resin tube 1 (tube body 11) is restricted to 0.3 mR (this is the allowable curvature for laying the optical fiber cable). Yes. In other words, the flexible synthetic resin pipe 1 is allowed to be allowed on the inner peripheral side by winding the pipe body 11 in a spiral shape without using a bending restricting member such as a pile when the pipe body 11 is bent. The cross-sectional shape restricts the bending radius to 0.3 mR.

Here, the cross-sectional shape of the flexible synthetic resin tube 1 when the allowable bending radius on the inner peripheral side when the tube body 11 is bent is regulated to 0.3 mR will be described.
The allowable bending radius of the tube main body 11 is such that the first engagement portion main body 17 (first engagement portion 13) and the second engagement portion main body 18 (second engagement portion 14) slide in the engaged state. Although calculated | required by the quantity S, this is made into the value calculated | required with the following formula | equation, and it sets in the range which considered the deformability of the inner-layer material 12.

That is, in obtaining the slide amount S, the circumferential length Co on the outer peripheral side of the curved portion of the flexible synthetic resin tube 1 is
Calculated by 2 × (Ri + D) × π. At this time, Ri is an allowable bending radius of the outer surface of the outer wall portion 171 of the first engaging portion main body 17 on the inner peripheral side when the tube main body 11 is bent, and D is an outer diameter of the tube main body 11.
Next, the circumferential length Ci on the inner peripheral side of the curved portion of the flexible synthetic resin tube 1 is
Calculated by 2 × (R−t) × π. At this time, R is an allowable bending radius of the inner surface of the inner wall portion 181 of the second engaging portion main body 18 on the inner peripheral side when the tube main body 11 is bent, and t is a thickness in the radial direction of the tube main body 11.
Then, based on the circumferential length Co on the outer peripheral side and the circumferential length Ci on the inner peripheral side, the slide amount S is obtained from the following equation.
S = (Co−Ci) × P1 / Ci
At this time, P <b> 1 is the length in the axial direction of the outer wall portion 171 of the first engagement portion main body 17.
For example, as a cross-section of the strip-like body 15 for manufacturing the flexible synthetic resin pipe 1 having an outer diameter D of the pipe body 11 of 75 mm, the length P1 in the axial direction of the outer wall part 171 of the first engagement part body 17 is used. Is 12 mm, the radial thickness t of the tube body 11 is 7 mm, and the slide amount S is 3 mm.

The inner layer material 12 is heat-sealed along the inner peripheral surface of the tube body 11. The inner layer material 12 desirably has a fusion strength of 0.2 MPa or more in order to prevent delamination against external water pressure, and desirably has a hardness in the range of 50 to 90 in order to achieve internal friction resistance. At this time, when the hardness exceeds 90, the flexibility is lost and it is difficult to bend. On the other hand, when the hardness is 50 or less, the internal friction resistance is increased and the communication cable cannot be passed after the construction.
Therefore, in the present invention, a non-plastic soft vinyl chloride resin (soft synthetic resin) is used as the inner layer material 12, and not a plasticizer but a thermoplastic elastomer to soften the non-plastic soft vinyl chloride resin. The softened soft vinyl chloride resin composition is applied. The degree of polymerization of the vinyl chloride resin is preferably in the range of 400 to 2400. If it is less than 400, high temperature molding is difficult, and if it exceeds 3000, it becomes hard and the surface properties deteriorate.
In view of this, the thermoplastic elastomer of the present invention is preferably a soft vinyl chloride resin composition containing a vinyl acetate elastomer, a polyester elastomer or a polyurethane elastomer. The ratio is preferably 20% to 80%, and if it is less than 20%, it becomes hard and the flexibility is impaired. On the other hand, if the ratio exceeds 80%, molding becomes difficult. This production method is not specified by a method such as reactive extrusion or mixing by a compound.
In order to reduce the internal frictional resistance, in addition to the above, as the crosslinked rubber, butadiene rubber, styrene butadiene styrene rubber, styrene isoprene styrene rubber, or thermoplastic elastomer, styrene elastomer, polyamide elastomer, Teflon elastomer ( Teflon can also be used as long as it does not impair the effects of the present invention, such as registered trademark) and polyether elastomers. In addition, fillers such as calcium carbonate, talc, mica and silica may be mixed. Further, stabilizers, colorants, lubricants and the like may be added as other additives.

Here, the inner surface static friction coefficient of the inner layer material 12 will be described.
In the present embodiment, since the communication cable is inserted into the flexible synthetic resin tube 1, the friction resistance between the inner surface of the inner layer material 12 and the communication cable is required to be small. In view of various actual piping conditions and the like, in order to draw the communication cable safely below the allowable tension of the communication cable, it is desirable that the static friction coefficient of the inner surface of the inner layer material 12 is 0.5 or less, and this value or less. The inner layer material 12 (elastomer) is selected. In this case, as shown in FIG. 9, in the experimental example (hardness: 68) using a soft vinyl chloride resin composition containing a vinyl acetate elastomer (content ratio: 50%) as the inner layer material 12, When the test rod Z was pulled in the direction of the arrow with respect to the inner surface of 12, an inner surface static friction coefficient of 0.35 to 0.45 was measured by the load meter Z1, and it was confirmed that the inner layer material 12 was satisfactory. The test bar Z was made of polyethylene having a length of 250 mm, an outer diameter of 34 mm, and a weight of 1 kg.

  Therefore, in the present embodiment, the opposing surface 183a of the first protrusion 184 of the second engagement part-side protrusion 183 becomes the tip side of the first protrusion 184 in the axial direction of the tube body 11. It inclines so that it may approach the 1st engaging part side protrusion 173 with respect to the orthogonal surface orthogonal to this. In addition, the facing surface 173a of the first engaging portion side ridge 173 is also more than the orthogonal surface orthogonal to this in the axial direction of the tube body 11 as it becomes the tip side of the first engaging portion side ridge 173. The second engaging portion side protrusion 183 is inclined so as to approach the first protrusion 184. For this reason, when the pipe body 11 is bent, the first engaging portion side protrusion 173 that contacts the first protruding portion 184 of the second engaging portion side protrusion 183 on the outer peripheral side thereof is As the engagement portion-side protrusion 183 becomes closer to the distal end side of the first protrusion 184, the engagement of the first protrusion 184 with respect to the facing surface 183a becomes stronger and it becomes difficult to move outward in the radial direction of the tube body 11. . Thereby, when the pipe body 11 is bent, the first engaging portion side protrusion 173 is disengaged from the facing surface 183a of the first protruding portion 184 of the second engaging portion side protrusion 183 on the outer peripheral side thereof. Is prevented, and the winding structure of the tube body 11 can be held smoothly.

In addition, the second engaging portion side protrusion 183 is formed thicker in the axial direction of the tube body 11 than the first engaging portion side protrusion 173, but there is a recess 180 that opens toward the tip. Since the first ridge 184 and the second ridge 185 are divided in the axial direction of the tube body 11 and are formed in a substantially V shape that opens outward, the first ridge 184 and The 1st engaging part 13 (1st engaging part main body 17) is uniformly supported from the inner side by the 2nd protrusion part 185, and the flatness of the pipe main body 11 can be prevented efficiently. And the material of the 2nd engaging part side protrusion 183 is reduced by the recessed part 180, and the cost reduction of the flexible synthetic resin pipe | tube 1 (pipe main body 11) can also be achieved.
Further, since the second engaging portion side ridge 183 is divided into the first protruding portion 184 and the second protruding portion 185, the remaining heat of the second engaging portion side ridge 183 which is thick is increased. When the tube body 11 is formed by spirally winding the injection-molded belt-like body 15 and forming the pipe body 11, the second engaging portion side protrusion that slides on the outer wall portion 171 of the first engaging portion main body 17 is formed. The fusion at the tips of the first protrusion 184 and the second protrusion 185 of the stripe 183 is alleviated, and the first engagement portion 13 and the second engagement portion 14 slide in the axial direction. As a result, the tube main body 11 can be easily formed.

  Further, when the tube main body 11 is bent, the opposite side of the first engaging portion side protrusion 173 that contacts the first engaging portion side surface 16a (the right side surface in FIG. 6) of the vertical wall portion 16 on the inner peripheral side thereof. The surface 173b forms a space that gradually increases in the axial direction of the tube main body 11 as it becomes the proximal end side of the first engaging portion side protrusion 173 between the vertical wall portion 16 and the first engaging portion side surface 16a. Therefore, when the tube body 11 is bent, the first engagement portion side surface 16a of the vertical wall portion 16 and the opposite flange surface 173b of the first engagement portion side protrusion 173 are formed on the inner peripheral side thereof. And abut so as to close the space. For this reason, even when a communication cable such as an optical fiber cable in which an allowable bending radius (for example, about 0.3 mR) is defined is accommodated inside the flexible synthetic resin tube 1, Further bending is restricted by bringing the both surfaces 16a and 173b into contact with each other on the inner peripheral side. Thereby, the malfunction by the disconnection etc. of a communication cable can be prevented reliably.

  Moreover, when a large axial force acts on the pipe body 11 due to ground fluctuations such as an earthquake, the pipe body 11 extends, and the inclination is increased in the direction in which the hook becomes stronger as it approaches the tip side, that is, the tip side is the first engagement. The facing surface 173a of the first engaging portion side ridge 173 inclined so as to be closer to the ridge of the joint portion is inclined in a direction in which the hook becomes stronger as it becomes the distal end side, that is, the distal end side is the first engaging portion side. The second engaging portion side protrusion 183 that is inclined so as to be closer to the protrusion 173 strongly contacts the facing surface 183a of the first protrusion 184. At this time, the first ridge portion of the second engagement portion side ridge 183 is brought into contact with the first engagement portion side ridge 173 and the first protrusion 184 of the second engagement portion side ridge 183. Even if the tip end of 184 is bent toward the side opposite to the first engaging portion side ridge 173, the tip end side is inclined closer to the first ridge portion 184 of the second engaging portion side ridge 183. By contact of the facing surface 173a of the protrusion 173 and the facing surface 183a of the first protrusion 184 of the second engaging portion-side protrusion 183 whose tip end is inclined closer to the first engaging portion-side protrusion 173. The first engaging portion side protrusion 173 can be smoothly held without going over the first protrusion 184 of the second engaging portion side protrusion 183 in the axial direction. Thereby, even if the pipe main body 11 extends due to ground fluctuation such as an earthquake, the winding structure of the pipe main body 11 can be held smoothly.

  In the first embodiment, the facing surface 173a of the first engaging portion side protrusion 173 is also moved in the axial direction of the tube main body 11 as it becomes the distal end side of the first engaging portion side protrusion 173. As shown in FIG. 10, the first engaging portion side protrusion 173 is opposed to the first engaging portion side protrusion 183. The surface 173a may extend in parallel with an orthogonal surface orthogonal to the axis of the tube body 11. Also in this case, when the tube main body 11 is bent, the first engaging portion side protrusion 173 becomes the distal end side of the first protruding portion 184 of the second engaging portion side protrusion 183 on the outer peripheral side thereof. Accordingly, the hook of the first protrusion 184 on the facing surface 183a is strengthened and it is difficult to move the pipe body 11 outward in the radial direction. Thereby, when the pipe body 11 is bent, the first engaging portion side protrusion 173 is disengaged from the facing surface 183a of the first protruding portion 184 of the second engaging portion side protrusion 183 on the outer peripheral side thereof. Is prevented, and the winding structure of the tube body 11 can be held smoothly.

Next, a second embodiment of the present invention will be described with reference to FIGS.
In this embodiment, the engagement pieces are provided at the tips of the first protrusions of the first engagement part side protrusions and the second engagement part side protrusions, respectively. The rest of the configuration excluding the engagement pieces is the same as in the first embodiment, and the same parts are denoted by the same reference numerals and detailed description thereof is omitted.
That is, in the present embodiment, as shown in FIGS. 11 to 15, the first protrusions 184 of the first engagement part side protrusions 173 and the second engagement part side protrusions 183 are opposed to each other. Engagement pieces 177 and 187 projecting in the axial direction of the tube main body 11 from the tip portions of the surfaces 173a and 183a are provided. The engagement pieces 177 and 187 are arranged on the first engagement portion side when the first engagement portion side protrusion 173 and the first protrusion 184 of the second engagement portion side protrusion 183 come into contact with each other. The first protrusions 184 of the protrusions 173 and the second engagement part side protrusions 183 can be engaged with each other from the inner and outer diameter directions to prevent separation.
In this case, the projecting surfaces of the engagement pieces 177 and 187 are formed on surfaces parallel to the first engagement portion side surface 16a of the vertical wall portion 16, respectively. Further, the opposing surface 183a of the first protrusion 184 of the second engagement part side protrusion 183 is inclined only on the base end side excluding the engagement piece 187.

  In this case, the first engagement portion side protrusion 173 and the first engagement portion side protrusion 183 of the first protrusion 184 are engaged from the inner and outer diameter directions by the respective engagement pieces 177 and 187. Therefore, when the pipe body 11 is bent, the engagement piece 177 of the first engagement portion side protrusion 173 that contacts the first protrusion 184 of the second engagement portion side protrusion 183 on the outer peripheral side thereof. Engages with the engaging piece 187 of the first protruding portion 184 of the second engaging portion side protrusion 183, along the opposing surface 183a of the second engaging portion side protrusion 183 (first protruding portion 184). This further prevents the pipe body 11 from moving outward in the radial direction. Thereby, when the pipe body 11 is bent, the first engaging portion side protrusion 173 is disengaged from the facing surface 183a of the first protruding portion 184 of the second engaging portion side protrusion 183 on the outer peripheral side thereof. Is reliably prevented, and the winding structure of the tube body 11 can be effectively retained.

  Moreover, when a large axial force acts on the pipe body 11 due to ground fluctuation such as an earthquake and the pipe body 11 extends, the tip side is inclined so as to be closer to the ridge of the first engaging portion. The first protrusion of the second engagement portion side protrusion 183 is inclined such that the opposite surface 173a of the first engagement portion side protrusion 173 is closer to the first engagement portion side protrusion 173. It strongly abuts against the facing surface 183a of the portion 184. At this time, due to the contact between the first engagement portion side protrusion 173 and the first engagement portion side protrusion 183 with the first protrusion 184, the tip of the first engagement portion side protrusion 173 is anti-second. Even if the tips of the first protrusions 184 of the second engagement part side protrusions 183 are bent toward the anti-first engagement part side protrusions 173 on the engagement part side protrusions 183 side, they are engaged with each other. By the engagement between the pieces 177 and 187, the first engagement portion side protrusion 173 can be reliably held without getting over the first protrusion 184 of the second engagement portion side protrusion 183 in the axial direction. Thereby, even if the pipe body 11 extends due to ground fluctuation such as an earthquake, the winding structure of the pipe body 11 can be reliably held.

  In the second embodiment, the first engaging portion side protrusion 173 and the first engaging portion side protrusion 183 of the first protrusion 184 are respectively provided at the tip portions of the facing surfaces 173a and 183a. The engagement pieces 177 and 187 projecting in the axial direction of the tube main body 11 are provided. However, as shown in FIGS. 16 and 17, the first engagement portion side protrusion 173 and the second engagement portion side protrusion 183 are provided. A plurality of engaging pieces 201 and 202 having a substantially triangular cross section that continuously protrude from the proximal end to the distal end may be provided on the opposing surfaces 173a and 183a of the first protrusion 184, respectively. In this case, when the tube main body 11 is bent, the first engaging portion side protrusion 173 and the first engaging portion side protrusion 183 of the first engaging portion side protrusion 183 are opposed to each other on the outer peripheral side. The engagement pieces 201 and 202 are quickly engaged with each other by the contact of 183a, and the first engagement portion side protrusion 173 with respect to the facing surface 183a of the first protrusion 184 of the second engagement portion side protrusion 183. The engagement of the opposite surface 173a is strengthened and the movement of the pipe body 11 outward in the radial direction is restricted. Thereby, when the pipe body 11 is bent, the first engaging portion side protrusion 173 is disengaged from the facing surface 183a of the first protruding portion 184 of the second engaging portion side protrusion 183 on the outer peripheral side thereof. Is more reliably prevented, and the winding structure of the tube body 11 can be firmly held.

In the second embodiment, the second engaging portion side ridge 183 is divided into a first ridge portion 184 and a second ridge portion 185 and is formed into a substantially V shape that opens outward. However, as shown in FIGS. 18 and 19, the first engaging portion side protrusion 173 is also formed thick in the axial direction of the pipe body 11 like the second engaging portion side protrusion 183. There is a recess 203 that opens toward the tip, and is divided into a first ridge 204 and a second ridge 205 in the axial direction of the tube body 11, and is formed into a substantially V shape that opens inward. Also good. The first protrusion 204 is located on the second engagement part side protrusion 183 side (right side in FIGS. 18 and 19), and the surface on the first engagement part side protrusion 183 side is the second. It is the opposing surface 173a of the engaging part side protrusion 173. Further, the surface on the vertical wall 16 side (the left side in FIGS. 18 and 19) of the second protrusion 205 is an opposite flange surface 173 b of the second engagement part-side protrusion 173. Furthermore, the first projecting portion 204 of the first engaging portion side ridge 173 and the tip portions of the opposing surfaces 173a and 183a of the first projecting portion 184 of the second engaging portion side ridge 183, respectively. Engagement pieces 177 and 187 projecting in the axial direction of the tube body 11 are provided.
Also in this case, the first protrusion 204 of the first engagement portion side protrusion 173 and the first protrusion 184 of the second engagement portion side protrusion 183 are connected to each other by the engagement pieces 177 and 187. Since it is engaged from the radial direction, when the tube body 11 is bent, the first engaging portion side protrusion that abuts the first protruding portion 184 of the second engaging portion side protrusion 183 on the outer peripheral side thereof. The engagement piece 177 of the first protrusion 204 of the line 173 engages with the engagement piece 187 of the first protrusion 184 of the second engagement part-side protrusion 183, and the second engagement part-side protrusion 183. It is further prevented that the pipe body 11 moves outward in the radial direction along the facing surface 183a of the (first protrusion 184). Thereby, when the pipe body 11 is bent, the first engagement portion side protrusion 173 of the first engagement portion side protrusion 173 from the facing surface 183a of the first protrusion portion 184 of the second engagement portion side protrusion 183 on the outer peripheral side thereof is obtained. The detachment of the first protrusion 204 is reliably prevented, and the winding structure of the pipe body 11 can be effectively held. Moreover, the first engaging portion side protrusion 173 is also formed thick in the axial direction of the tube main body 11 similarly to the second engaging portion side protrusion 183, and has a recess 203 that opens toward the tip. In the axial direction of the pipe body 11, the first ridge 204 is divided into the first ridge 204 and the second ridge 205, and is formed in a substantially V shape that opens inward. In addition, the second engaging portion 14 (second engaging portion main body 18) is uniformly supported from the outside by the second protrusions 205, and the flatness of the tube main body 11 can be prevented more efficiently. Accordingly, the material of the first engaging portion side protrusion 173 can be reduced, and the cost of the flexible synthetic resin tube 1 (tube body 11) can be reduced.

Next, a third embodiment of the present invention will be described with reference to FIGS.
In this embodiment, the shape of the second engaging portion side protrusion is changed. In addition, the structure other than the 2nd engaging part side protrusion is the same as that of the said 1st Embodiment, The same code | symbol is attached | subjected about the same part and the detailed description is abbreviate | omitted.
That is, in the present embodiment, as shown in FIGS. 20 to 24, the second engagement portion main body 18 has a tube main body 11 from a wide range from the substantially central portion of the inner wall portion 181 to the tip (right end in FIG. 21). The second engaging portion side protrusion 188 (protrusion) projecting outward in the radial direction (upward in FIG. 21). The second engaging portion side protrusion 188 is formed to be thicker (for example, about 2 to 3 times thicker) in the axial direction of the tube body 11 than the first engaging portion side protrusion 173.

  Further, the facing surface 188a of the second engaging portion side ridge 188 is formed in a direction that is perpendicular to the orthogonal surface perpendicular to the axial direction of the tube body 11 as it becomes the tip side of the second engaging portion side ridge 188. It inclines so that the 1 engaging part side protrusion 173 may approach.

  Therefore, in the present embodiment, the facing surface 188a of the second engaging portion side protrusion 188 is orthogonal to the axial direction of the tube main body 11 as it becomes the tip side of the second engaging portion side protrusion 188. Since it is inclined to approach the first engaging portion side protrusion 173 with respect to the orthogonal surface, the tube main body 11 is curved in combination with the inclination of the facing surface 173a of the first engaging portion side protrusion 173. The first engagement portion side protrusion 173 that contacts the second engagement portion side protrusion 188 on the outer peripheral side of the second engagement portion side protrusion 188 becomes the second end as the second engagement portion side protrusion 188 becomes the front end side. Engagement of the engaging portion side protrusion 188 with respect to the facing surface 188a becomes strong, making it difficult to move outward in the radial direction of the tube body 11. Thus, when the tube body 11 is bent, the first engagement portion side protrusion 173 is prevented from being detached from the facing surface 188a of the second engagement portion side protrusion 188 on the outer peripheral side thereof. The winding structure can be held smoothly.

  Further, since the second engaging portion side protrusion 188 is formed thicker in the axial direction of the pipe body 11 than the first engaging portion side protrusion 173, the second engaging portion side protrusion 188 is The first engaging portion 13 is supported from the inside, and the flatness of the tube body 11 can be prevented.

Next, a fourth embodiment of the present invention will be described with reference to FIGS.
In this embodiment, engagement pieces are provided at the tips of the first engagement portion side protrusions and the second engagement portion side protrusions of the third embodiment. The rest of the configuration excluding the engagement pieces is the same as that of the third embodiment, and the same parts are denoted by the same reference numerals and detailed description thereof is omitted.
That is, in this embodiment, as shown in FIGS. 25 to 27, the first engaging portion side protrusion 173 and the second engaging portion side protrusion 188 are provided at the tip portions of the opposing surfaces 173 a and 188 a. Further, engagement pieces 177 and 187 projecting in the axial direction of the tube body 11 are provided. Each of the engagement pieces 177 and 187 has the first engagement portion side protrusion 173 and the second engagement when the first engagement portion side protrusion 173 and the second engagement portion side protrusion 188 come into contact with each other. The joint-side protrusions 188 are engaged with each other from the inner and outer diameter directions. In this case, the projecting surfaces of the engagement pieces 177 and 187 are formed in parallel with orthogonal surfaces orthogonal to the axial direction of the tube body 11. Further, the opposing surface 188 a of the second engaging portion side protrusion 188 is inclined only on the base end side excluding the engaging piece 187.

  In this case, the first engagement portion side protrusion 173 and the second engagement portion side protrusion 188 are engaged from each other by the engagement pieces 177 and 187 from the inner and outer diameter directions. When the first engaging portion side protrusion 173 is in contact with the second engaging portion side protrusion 188 on the outer peripheral side when bent, the engaging piece 177 is engaged with the second engaging portion side protrusion 188. It engages with the joint piece 187 and is prevented from moving outward in the radial direction of the tube body 11 along the opposing surface 188a of the second engaging portion side protrusion 188. Thus, when the tube main body 11 is bent, the first engagement portion side protrusion 173 is reliably prevented from being detached from the facing surface 188a of the second engagement portion side protrusion 188 on the outer peripheral side thereof. The winding structure of the main body 11 can be effectively retained.

The present invention is not limited to the above-described embodiments, and includes other various modifications. For example, in each of the embodiments described above, the second engaging portion side protrusions 183 and 188 are formed thicker in the axial direction of the tube body 11 than the first engaging portion side protrusions 173. Based on the circumferential length Co, the circumferential length Ci on the inner circumferential side, and the length P1 in the axial direction of the outer wall portion 171 of the first engaging portion main body 17, the slide amount S is calculated using the above-described equation (S = (Co -Ci) × P1 / Ci), the second engagement portion side protrusion 189 is substantially equivalent to the first engagement portion side protrusion 173 as shown in FIG. The tube body 11 may be formed to have a thickness in the axial direction. In addition, in this modification, the opposing surface 189a of the second engaging portion side protrusion 189 becomes orthogonal to the axial direction of the tube main body 11 as it becomes the tip side of the second engaging portion side protrusion 188. While the surface is inclined so as to approach the first engaging portion side protrusion 173, the facing surface 173a of the first engaging portion side protrusion 173 is extended in parallel with an orthogonal surface orthogonal to the axis of the tube body 11. The opposing surface of the first engaging portion side ridge is on the second engaging portion side with respect to the orthogonal surface perpendicular to the axial direction of the tube body as it becomes the tip side of the first engaging portion side ridge. Needless to say, it may be inclined so as to approach the ridge.
Further, as shown in FIG. 29, the second engaging portion side protrusion 189 and the first engaging portion side protrusion 173 described in the above modification are respectively connected to the pipes from the tip portions of the facing surfaces 173a and 189a. Engagement pieces 177 and 187 protruding in the axial direction of the main body 11 may be provided. In this case, since the opposing surface 173a of the first engaging portion side protrusion 173 and the opposing surface 189a of the second engaging portion side protrusion 189 are inclined, when the pipe body 11 is bent, When the engagement piece 177 of the first engagement portion side protrusion 173 that contacts the second engagement portion side protrusion 189 on the outer peripheral side engages with the engagement piece 187 of the second engagement portion side protrusion 189, The detachment of the first engaging portion side protrusion 173 from the facing surface 189a of the second engaging portion side protrusion 189 can be reliably prevented, and the winding structure of the pipe body 11 can be effectively retained.

  In each of the above embodiments, the first engagement portion side protrusion 173 is disposed between the opposite flange surface 173 b of the first engagement portion side protrusion 173 and the first engagement portion side surface 16 a of the vertical wall portion 16. As the base end side of the tube body 11 is inclined, a slope is formed so as to form a space that gradually increases in the axial direction of the tube body 11, but the first engagement portion side surface of the vertical wall portion is opposite to the first engagement portion side protrusion. It is inclined so as to form a space that gradually increases in the axial direction of the pipe body as it goes to the outer end (radially outer end of the pipe body) side of the vertical wall part, or the first of the vertical wall part Both the engaging portion side surface and the opposite flange surface of the first engaging portion side protrusion may be inclined.

  Further, in each of the above embodiments, the facing surface 183a of the first protruding portion 184 of the second engaging portion side protrusion 183 or the facing surfaces 188a, 189a of the second engaging portion side protrusion 188, 189, and the first The opposing surface 173a of the first engaging portion side protrusion 173 is inclined with respect to the orthogonal surface orthogonal to the axial direction of the tube main body 11, but the first engaging portion side protrusion of the first engaging portion side protrusion 173 is opposed to the first engaging portion side protrusion 173. The opposing surface of the surface or the second engaging portion side ridge and the opposing surface of the first engaging portion side ridge are parallel to an orthogonal surface orthogonal to the axial direction of the pipe body, and this first engaging portion side Engagement pieces that protrude in the axial direction of the tube main body from the tip portion may be provided on the opposing surfaces of the protrusion and the second engagement portion side protrusion, respectively. In this case, when the tube main body is bent, the protrusion of the first engagement portion from the opposite surface of the protrusion of the second engagement portion on the outer peripheral side is reliably prevented, and the tube main body The winding structure can be effectively held.

DESCRIPTION OF SYMBOLS 1 Flexible synthetic resin pipe | tube 11 Pipe | tube main body 12 Inner layer material 13 1st engaging part 14 2nd engaging part 15 Strip | belt-shaped body 16a The 1st engaging part side surface (vertical surface of a 2nd engaging part) of a vertical wall part
173 1st engaging part side protrusion (protrusion)
173a Opposite face 173b Opposite face 177, 187, 201, 202 Engagement piece 180, 203 Recess 183, 188, 189 Second engagement part side ridge (protrusion)
183a, 188a, 189a

Claims (7)

It is made of synthetic resin, a first engagement portion is formed along one side in the axial direction, and a second engagement portion is formed along the other side in the axial direction as a connection with the first engagement portion. The body is wound in a spiral shape, and the first engagement portion and the second engagement portion adjacent to the first engagement portion are engaged with each other in a non-bonded state so as to be slidable in the axial direction. Having a tube body formed by turning,
In a flexible synthetic resin tube in which an inner layer material made of a soft synthetic resin is adhered along the inner peripheral surface of the tube main body,
The first engaging portion engages with a second engaging portion adjacent thereto from the outside in the radial direction of the tube main body, and the both engaging portions face each other in the axial direction of the tube main body. And are provided with protrusions that slide and contact each other in the axial direction when the tube body is curved,
A flexible synthetic resin characterized in that the opposing surface of the protrusion of the second engaging portion is inclined so as to approach the protrusion of the first engaging portion as it comes to the tip side of the protrusion. tube.   2. The flexible composition according to claim 1, wherein the opposing surface of the protrusion of the first engagement portion is inclined so as to approach the protrusion of the second engagement portion as it comes to the tip side of the protrusion. Resin tube.   The protrusions of the two engaging portions protrude in the axial direction from the tip portions of the opposing surfaces of the engaging portions, and engage pieces that engage the protrusions from the inner and outer diameter directions when the protrusions abut. The flexible synthetic resin pipe according to claim 1 or 2, further comprising:   4. The protrusion according to claim 1, wherein the protrusion of the second engagement portion is formed thicker in the axial direction of the pipe body than the protrusion of the first engagement portion. 5. Flexible plastic tube.   The protrusion of the said 2nd engaging part is provided with the recessed part opened toward the front-end | tip, and several protrusions divided | segmented into the axial direction of the said pipe | tube main body by this recessed part. Flexible plastic tube. The opposite flange surface of the protrusion of the first engagement portion and the vertical surface of the second engagement portion adjacent to the first engagement portion are mutually on the inner peripheral side when the tube body is curved. Abut,
As at least one of the opposite flange surface of the protrusion of the first engagement portion and the vertical surface of the second engagement portion becomes the base end side of the protrusion of the first engagement portion between the both surfaces. The flexible synthetic resin pipe according to any one of claims 1 to 5, which is inclined so as to form a space that gradually increases in the axial direction of the pipe body. It is made of synthetic resin, a first engagement portion is formed along one side in the axial direction, and a second engagement portion is formed along the other side in the axial direction as a connection with the first engagement portion. The body is wound in a spiral shape, and the first engagement portion and the second engagement portion adjacent to the first engagement portion are engaged with each other in a non-bonded state so as to be slidable in the axial direction. Having a tube body formed by turning,
In a flexible synthetic resin tube in which an inner layer material made of a soft synthetic resin is adhered along the inner peripheral surface of the tube main body,
The first engaging portion engages with a second engaging portion adjacent thereto from the outside in the radial direction of the tube main body, and the both engaging portions face each other in the axial direction of the tube main body. And are provided with protrusions that slide and contact each other in the axial direction when the tube body is curved,
The protrusions of the two engaging portions protrude in the axial direction from the tip portions of the opposing surfaces of the engaging portions, and engage pieces that engage the protrusions from the inner and outer diameter directions when the protrusions abut. A flexible synthetic resin tube characterized by comprising:

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