JP2009108988A - Flexible pressure-resisting synthetic resin pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure-resisting synthetic resin pipe having excellent flexibility, exhibiting uniform compression strength over the whole length even if it is curved, and capable of being greatly curved to a desired degree of curvature without generating excessive residual stress. <P>SOLUTION: A hard synthetic resin belt-like member having a constant width is spirally wound at a constant pitch around the peripheral surface of a soft synthetic resin pipe 1, and the inner peripheral surface at one end of the belt-like member is integrally fixed to the outer peripheral surface of the soft synthetic resin pipe 1. Thereby, the end inner peripheral surface of a hard covering piece 2a composed of the belt-like member wound by one turn next is superposed slidably in a pipe length direction on the base outer peripheral surface of the hard covering piece 2a composed of the belt-like member wound by one turn first. Further, an inward locking piece 4 is provided at the end of the hard covering piece 2a, and an outward locking piece 3 is provided at the base end thereof. Accordingly, the locking pieces 3, 4 of the hard covering piece 2a which are adjacent to each other when the pipe is curved are locked to each other. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a pressure-resistant synthetic resin tube suitable for use as a fluid supply tube such as a drain tube or a buried underground tube or a wire protection tube that requires flexibility and pressure resistance.

  Conventionally, as a synthetic resin tube having flexibility, there is a soft synthetic resin tube, and as a synthetic resin tube having pressure resistance, a hard synthetic resin tube is known, but in the case of a soft synthetic resin tube, Can not be used in places subject to external pressure such as earth pressure because of its weak pressure resistance, but in the case of hard synthetic resin pipes it has little flexibility, so it is easy to work and handle There is a problem of causing difficulty.

  For this reason, for example, as described in Patent Document 1, a hard synthetic resin strip having a certain width on the outer peripheral surface of the soft synthetic resin tube is fixed to be shorter than the width of the hard synthetic resin strip. A spiral winding with a pitch, and the inner peripheral surface of one end thereof is fixed to the top of a fixed height spiral ridge wound around the outer peripheral surface of a soft synthetic resin tube with the same spiral pitch as above. In addition, the leading end of the next strip of the strip-shaped material portion is slidably overlapped in the length direction of the tube on the base of the strip-shaped material portion that has been wound once. Thus, a pressure-resistant synthetic resin pipe having a hard synthetic resin outer shell formed by covering the entire outer surface of a soft synthetic resin has been developed.

Japanese Patent Laid-Open No. 2004-19701

  According to the pressure-resistant synthetic resin pipe, the soft synthetic resin pipe can be entirely covered and protected by the hard synthetic resin outer shell formed by spirally winding the hard synthetic resin strip, and the entire length is covered. Uniform pressure resistance can be achieved, and when bending, adjacent strips overlapping in the length direction of the tube slide in the direction of the tube axis to bring the soft synthetic resin tube outside. It has the advantage that it can be bent to a desired degree of curvature without being exposed. However, when this pressure-resistant synthetic resin tube is curved in an arc shape, a tensile force is generated in the outer peripheral wall portion of the soft synthetic resin tube curved in a convex arc shape, and in the inner peripheral wall portion curved in a concave arc shape Although compressive force is generated, if it is bent in a large arc shape, excessive residual stress due to excessive tensile force is generated on the outer peripheral wall portion of the soft synthetic resin pipe, and if the pipe wall is piped in this state, the pipe wall portion There was a risk of deterioration and damage in a short period of time.

  Furthermore, when the pressure-resistant synthetic resin pipe is curved in an arc shape, the hard synthetic resin strip-shaped material covering the outer peripheral wall portion of the soft synthetic resin pipe curved in a convex arc shape is made of an adjacent hard synthetic resin. In the band-shaped material part, the other band-shaped material part overlaid on the base of one band-shaped material part is, with the base end fixed to the outer peripheral surface of the soft synthetic resin pipe via the spiral protrusion as a fulcrum, Pushed up by the base end of one band-shaped material part, the gap between the tip of the other band-shaped material part and the outer peripheral surface of one band-shaped material part expands in a wedge shape. There is a problem that the belt-shaped material portion is damaged by invading so that the pressure-resistant synthetic resin pipe must be replaced in a short period of time.

  The present invention has been made in view of the above problems, and its object is to have excellent pressure strength and wear resistance, exhibit good flexibility, and It can be bent to the desired degree of curvature without causing excessive stress and is not easily damaged. In addition, it can be used for a long time in response to unequal subsidence and tensile force during an earthquake. It is in providing a pressure-resistant synthetic resin tube that can.

  In order to achieve the above object, the flexible pressure-resistant synthetic resin pipe according to the present invention is a rigid synthetic resin strip having a certain width on the outer peripheral surface of the soft synthetic resin pipe as described in claim 1. Is wound spirally at a constant pitch shorter than the width of the hard synthetic resin strip and the inner peripheral surface of one end thereof is fixed to the outer peripheral surface of the soft synthetic resin tube, and is wound once. A soft synthetic resin pipe is slidably overlapped on the base of the hard-coated piece portion made of a strip-like material portion and then slidable in the length direction of the tube. In a pressure-resistant synthetic resin tube forming a hard synthetic resin outer shell that covers the entire outer surface of the base, a predetermined interval from the outer peripheral surface of the proximal end portion of the hard coating piece portion to the distal end portion thereof. An outer locking piece and an inward locking piece are respectively provided on the existing inner peripheral surface, and the tube Characterized in that the inward locking piece of the other hard cover strip section outwardly locking piece of one of the hard cover strip portion in the hard cover strip portions adjacent the structure engageable upon curved.

  In the flexible pressure-resistant synthetic resin tube configured as described above, the invention according to claim 2 is characterized in that an inwardly engaging piece is provided at the tip of the hard coating piece, and according to claim 3, According to the invention, the outward locking piece is formed in a hook shape opening toward the distal end side of the hard coating piece portion, while the inward locking piece is formed on the proximal end side of the hard coating piece portion. It is characterized by being formed in a hook shape opening toward the front.

  A hard synthetic resin strip having a certain width on the outer peripheral surface of a soft synthetic resin pipe is spirally wound at a constant pitch shorter than the width of the hard synthetic resin strip, and the inner peripheral surface of one end thereof is soft. The tip of the hard-covered piece portion made of the belt-shaped material portion wound next is wound on the base portion of the hard-covered piece portion made of the belt-shaped material portion wound one time before being fixed to the outer peripheral surface of the synthetic resin pipe. Since it is slidably overlapped in the length direction of the pipe, a hard synthetic resin outer shell that covers the entire outer surface of the soft synthetic resin pipe is formed by this hard synthetic resin strip. The outer shell made of hard synthetic resin can fully protect the soft synthetic resin pipe and can exhibit excellent pressure strength and wear resistance. In addition, the soft synthetic resin pipe is made of hard synthetic resin. Is it entirely covered with a resin shell? However, when it is curved, the hard covering pieces made of the strip-shaped material portions superposed on the scales of the cross section forming the hard synthetic resin outer shell slide in the tube axis direction and smoothly bend. be able to.

  Furthermore, an outward locking piece and an inward locking piece are respectively provided on the outer peripheral surface of the base end portion of the hard covering piece portion and the inner peripheral surface having a predetermined interval from the base end portion toward the distal end portion. Since, when the tube is bent, the inwardly engaging piece of the other hard coating piece portion can be engaged with the outwardly engaging piece of the one hard coating piece portion in the adjacent hard covering piece portion. When this pressure-resistant synthetic resin tube is curved, on the outer peripheral wall side of the soft synthetic resin tube that curves in a convex arc shape, the inner and outer locking pieces of these adjacent hard-covered piece portions are locked to each other for soft synthesis. It is possible to reliably prevent further tensile force from acting on the outer peripheral wall of the resin pipe, and therefore, construct a pressure-resistant synthetic resin pipe without leaving excessive tensile stress in the soft synthetic resin pipe. That can be used for long-term use. In the hard coating piece portion that comes into contact, the inner and outer locking pieces are locked to each other so that no further tensile force is generated, and then the soft synthetic resin with the locking portion between these inner and outer locking pieces as a fulcrum The entire pipe can be greatly bent while further compressing the inner peripheral wall portion of the pipe making that is curved in a concave arc shape.

  Further, when the pressure-resistant synthetic resin tube is bent so that the inner and outer locking pieces of the adjacent hard covering piece portions are locked with each other, the adjacent hard covering piece portion slides further in the tube axis direction. Since they are not separated from each other, the soft synthetic resin pipes can always be entirely covered with the hard synthetic resin outer shell made of these hard coated pieces even if they are greatly curved, and they are also connected to each other. By stopping the inner and outer locking pieces, it is possible to reliably prevent the sand and the like from entering between the adjacent hard coating pieces, and as described above, the outward locking pieces and the inward locking pieces. Not only is it possible to prevent the occurrence of excessive stress when the tube is bent by engagement with the piece, it can also prevent unreasonable deformation in response to unequal settlement and tensile force that occurs during an earthquake, Therefore, even if it is used as piping buried in the ground It is possible to maintain a stable construction state for a long period of time.

  The outward locking piece is provided on the outer peripheral surface of the base end portion of the hard coating piece portion, but the inward locking piece has a predetermined interval from the outward locking piece toward the distal end portion of the hard coating piece portion. May be provided on the inner peripheral surface of the intermediate portion, and as described in claim 2, it may be provided on the inner peripheral surface of the distal end portion of the hard covering piece portion.

  Furthermore, according to the invention according to claim 3, in the inner and outer locking pieces provided on the hard covering piece portion covered with the soft synthetic resin pipe, the outward locking piece is directed toward the distal end side of the hard covering piece portion. The inward locking piece is formed into a hook shape that opens toward the base end side of the hard cover piece, so the hard cover piece is curved. Then, in the hard covering piece portions adjacent to each other in the front and back, while sliding the inwardly engaging pieces provided on one hard covering piece portion on the outer peripheral surface of the other hard covering piece portion, The outward locking piece provided at the base end of the hard coating piece can be brought into close contact with each other while sliding on the inner peripheral surface of one hard coating piece, and the locked state Even if the pressure-resistant synthetic resin tube is bent further, the outward locking piece will come off the inward locking piece. Risk without, it can be reliably kept maintained locking state of overlap without gaps.

  Next, a specific embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a simplified side view of a part of a flexible pressure-resistant synthetic resin pipe A, and FIG. 2 is a part of it. The pressure-resistant synthetic resin pipe A is a hard synthetic resin outer shell made of hard vinyl chloride that can be bent and deformed on the outer peripheral surface of the soft synthetic resin pipe 1 having a certain thickness made of soft vinyl chloride. 2 is covered. The soft synthetic resin pipe 1 and the hard synthetic resin outer shell 2 are made of soft and hard vinyl chloride resin, respectively, but are made of other homogeneous materials having good adhesion and different hardness. You may form from a resin material, for example, a soft polyethylene resin, a hard polyethylene resin, etc.

  The hard synthetic resin outer shell 2 is formed of a hard synthetic resin strip having a constant width on the outer peripheral surface of the soft synthetic resin pipe 1 with a constant pitch shorter than the width of the hard synthetic resin strip. The inner surface of the one end portion in the width direction is wound in a spiral shape while being integrally fixed to the outer peripheral surface of the soft synthetic resin tube 1 by heat fusion, and is formed by a strip-shaped material portion that is wound in a single turn. The other half part of the hard covering piece 2a formed by the belt-like material portion wound next around on one half of the hard covering piece 2a is slid in the length direction of the soft synthetic resin pipe 1 At the both ends of these hard-coated pieces 2a that are superposed freely and are oriented in the length direction of the soft synthetic resin pipe 1, they are fixed to the outer peripheral surface of the soft synthetic resin pipe 1 by heat fusion. One end side is the base end, and the other end side is the front end, and outward toward the outer peripheral surface of the base end The locking piece 3 is provided with an inward locking pieces 4 respectively on the tip inner peripheral surface.

  Therefore, in the adjacent hard covering piece portions 2a and 2a, the inward locking piece 3 provided at the distal end portion of the one hard covering piece portion 2a is the outer portion provided at the proximal end portion of the other hard covering piece portion 2a. It is slidably supported in the length direction of the pipe on the outer peripheral surface of the other hard covering piece portion 2a with a certain distance in the length direction of the soft synthetic resin pipe 1 from the direction locking piece 3. When the synthetic resin pipe A is bent, the outer peripheral wall portion that curves in a convex arc shape engages the inner and outer locking pieces 3 and 4 of the adjacent hard coating piece portions 2a and 2a, and curves in a concave arc shape. In the inner peripheral wall portion, the inner and outer locking pieces 3 and 4 are configured to be separated from each other.

  The outward locking piece 3 provided at the base end portion of the hard coating piece portion 2a is bent so that the base end portion of the hard coating piece portion 2a is folded back toward the outer peripheral surface side. The inward locking piece 3 provided at the tip of the hard cover piece 2a is folded back toward the inner peripheral surface while being formed in a hook shape that opens toward the tip of 2a. By being bent in this way, it is formed in a hook shape opening toward the base end side.

  Further, the hard covering piece 2a is fixed to the outer peripheral surface of the soft synthetic resin pipe 1 by heat-sealing the inner peripheral surface of the base end portion to a constant thickness from the proximal end portion to the distal end portion. However, the inner peripheral surface side of the base end portion may be formed thick, and the inner peripheral surface of the thick portion may be fixed to the outer peripheral surface of the soft synthetic resin pipe 1 by heat fusion, A hard synthetic resin string-like material made of the same material as the hard synthetic resin belt-like material forming the hard covering piece 2a on the soft synthetic resin pipe 1 is spirally wound at the same pitch as the hard synthetic resin belt-like material. As shown in FIG. 2, a hard spiral ridge 5 is provided by rotating and fixing by heat fusion, and the inner peripheral surface of the base end portion of the hard coating piece 2a is fixed on the hard spiral ridge 5 by heat fusion. You may keep it.

  In this way, the base end portion of the hard covering piece 2a is formed thick and the thick portion is fixed to the outer peripheral surface of the soft synthetic resin tube 1 or the hard spiral protrusion on the soft synthetic resin tube 1. According to the structure in which 5 is integrally provided and the base end portion of the hard covering piece 2a is integrally fixed on the hard covering piece portion 5, the soft synthetic resin pipe 1 is formed by the thick portion or the hard spiral ridge 5. It is difficult to cause crushing deformation, and it is possible to exhibit a further excellent pressure strength together with the hard coating piece 2a.

  When the pressure-resistant synthetic resin pipe A configured as described above is curved in an arc shape as shown in FIG. 3, the soft synthetic resin pipe 1 is easily bent and the hard synthetic resin pipe 1 is made together with the soft synthetic resin pipe 1. The shell 2 is also bent integrally. At this time, in the outer peripheral wall portion A1 curved in a convex arc shape, a tensile force is generated in the tube axis direction, and the soft synthetic resin tube wall portion between adjacent hard spiral ridge portions is tensioned, and the tube wall The adjacent hard spiral strips 2a and 2a are spaced apart from each other by the convex arc-shaped curve of the portion, and the inwardly engaging pieces provided at the tip of one of the hard coated strips 2a 4 slides on the outer peripheral surface of the other hard-covered piece 2a toward the base end of the other hard-covered piece 2a, and the outward engagement provided at the base end of the other hard-covered piece 2a. The stop piece 3 slides on the inner peripheral surface of one hard covering piece portion 2a toward the tip of the hard covering piece portion 2a so that the outward locking pieces 3 and the inward locking pieces 4 are mutually connected. When the pressure-resistant synthetic resin pipe A is further curved, both the locking pieces 3 and 4 are locked to each other so that the space between adjacent hard spiral ridges is Furthermore, in the locked state without roller separation, excessive tensile force to the outer peripheral wall portion which is curved in a convex arc shape of the soft synthetic resin pipe 1 is prevented.

  On the other hand, in the inner peripheral wall portion A2 curved in a concave arc shape of the pressure-resistant synthetic resin tube A, a compressive force is generated in the tube axis direction, and the adjacent hard spiral ridges approach each other by the compressive force. The soft synthetic resin tube wall between the hard spiral ridges is relaxed and folded in a zigzag shape toward the inside of the tube, and one of the hard cover pieces 2a, 2a is adjacent to the hard cover piece. The inward engagement piece 4 provided at the tip of the portion 2a slides on the outer peripheral surface of the other hard coating piece 2a toward the tip of the other hard coating piece 2a and the other hard coating piece. All the hard covering pieces are formed by the outward locking pieces 3 provided at the base end of the portion 2a sliding on the inner peripheral surface of one hard covering piece portion 2a toward the base end of the hard covering piece portion 2a. The portions 2a overlap with each other and stand outward from the proximal end side toward the distal end side.

  In addition, on the side of the outer peripheral wall portion A2 curved in a convex arc shape of the pressure resistant synthetic resin tube A, from the state where the outward locking piece 3 and the inward locking piece 4 are locked as described above, the pressure resistant synthetic resin tube When A is further curved, the inner peripheral wall portion of the pressure-resistant synthetic resin pipe A is further compressed in the tube length direction by using the locking portions of the outward locking pieces 3 and the inward locking pieces 4 as fulcrums. Can be curved to a greater extent.

  Therefore, for example, when this pressure-resistant synthetic resin pipe A is laid as a drain pipe under the floor or in the ground, it can be piped as planned while being bent freely, and foreign matter such as earth and sand is made of hard synthetic resin outer shell. The inner circumference of the soft synthetic resin pipe 1 which is reliably prevented from entering the inner surface side of the pipe 2 and can be used for a long period of time, and which is entirely covered with the outer shell 2 made of hard synthetic resin Since the surface is formed as a relatively flat surface in the length direction, smooth circulation is possible. Further, even if a tensile force acts on the pressure-resistant synthetic resin tube A and the soft synthetic resin tube 1 is expanded, the outward locking piece 3 and the inward locking piece 4 are locked and further extension is caused. It is possible to prevent the soft synthetic resin pipe 1 from being broken, and when used as a buried pipe as described above, even if uneven settlement occurs during an earthquake, excessive bending and elongation may occur. Since it can prevent, stable construction is attained. In addition, this pressure-resistant synthetic resin pipe A can also be embed | buried and used in the ground as a protective tube of an electric wire.

  Next, the manufacturing method of the pressure-resistant synthetic resin pipe A configured as described above will be briefly described with reference to FIG. 4. A soft synthetic resin strip 1 made of a soft vinyl chloride resin in a semi-molten state having a certain width and thickness. As is well known, while extruding 'from the first molding nozzle 11, the other side portion of the following strip-shaped material portion 1 a is superimposed on one side portion of the preceding strip-shaped material portion 1 a on the base end portion of the molding rotating shaft 10. As a result, a soft synthetic resin pipe 1 having a constant thickness with a flat inner and outer peripheral surface is formed by winding it in a spiral with a constant pitch while being integrally welded, and on the soft synthetic resin pipe 1 Next, while extruding a hard synthetic resin string-like material 5 'made of a semi-molten hard vinyl chloride resin having a rectangular or elliptical cross section from the second molding nozzle 12, it is wound in a spiral at a constant pitch and heated. Hard by sticking by fusion To form a spiral ridge 5.

  Further, the third molding nozzle 13 is made of a hard synthetic resin in a semi-molten state made of the same material as the hard synthetic resin string-like material 5 'and having a width approximately twice as wide as the winding pitch of the string-like material 5'. A band-shaped material 2 ′, which is a hook-shaped outward locking piece 3 ′ on one long edge of the hard synthetic resin-shaped band 2 ′, and a hook-shaped inward locking on the other long edge end. While extruding each piece 4 'integrally, the outer periphery of the soft synthetic resin tube 1 is fused while only the back surface of the outward locking piece 3' is fused on the hard spiral ridge 5 integrally. On the surface, the strip-shaped material portion 2a 'wound next is wound on one half of the width direction of the strip-shaped material portion 2a' previously wound, and the other half portion in the width direction is sequentially overlapped in a cross-sectional shape in a string shape. By winding spirally at the same pitch as the material 5 ', the strip-shaped material portion 2a' causes the outward locking piece 3 at one end in the longitudinal direction of the tube and the inward at the other end. The hard cover strip portion 2a formed by providing the locking piece 4 to form a hard synthetic resin shell 2 formed by winding spiral.

  At this time, before the semi-molten hard synthetic resin strip 2 'is spirally wound on the soft synthetic resin tube 1, the semi-molten hard synthetic resin strip 2 extruded from the third molding nozzle 13 is used. 'Is passed through a cooling device 14 by blowing cold air, etc., and when the strips 2a' and 2a 'are overlapped on the soft synthetic resin pipe 1, they are wound spirally without being fused together, Only the inner surface (back surface) of the outward locking piece portion 3 ′ is heated and melted by the heating device 15 to be integrally fused onto the hard spiral ridge 5.

  In this way, a flexible pressure-resistant synthetic resin tube having a hard synthetic resin outer shell 2 provided on the outer peripheral surface of the soft synthetic resin tube 1 is continuously manufactured on the molding rotary shaft 10, and is formed for each desired length. The pressure-resistant synthetic resin pipe A having a predetermined length is obtained by cutting. In the above embodiment, the hard synthetic resin string-like material 5 ′ is fused to the outer peripheral surface of the soft synthetic resin tube 1, and the hard synthetic resin string-like material 5 ′ is attached to both ends. The inner peripheral surface of one end portion of the hard synthetic resin strip 2 'provided with the direction locking piece 3' and the inward locking piece portion 4 'is fixed by fusion bonding. Made of soft synthetic resin without thickening or thickening the inner peripheral surface of one end portion having the outward locking piece 3 'of the hard synthetic resin strip 2' without using the material 5 ' It may be fused directly to the outer peripheral surface of the tube 1.

  FIG. 5 shows another embodiment of the flexible pressure-resistant synthetic resin pipe A ′ according to the present invention. In the above-described embodiment, a hard covering piece forming a hard synthetic resin outer shell 2 is shown. An inward engagement piece 4 is formed at the distal end of the portion 2a. In this pressure-resistant synthetic resin tube A ', an inner peripheral surface with a predetermined distance from the distal end of the hard coating piece 2a toward the proximal end An inward locking piece 4 is formed in the inner locking piece 4, and the tip of the hard coating piece 2a is extended from the inward locking piece 4. The width between the proximal end and the distal end of the hard covering piece portion 2a in the length direction of the tube is provided with an outward locking piece 3 and an inward locking piece 4 at both ends shown in the above embodiment. It may be the same width as the hard coating piece 2a, or it may be formed widely. Since other configurations are the same as those of the above-described embodiment, the same portions are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 6 shows still another embodiment of the flexible pressure-resistant synthetic resin pipe A ″ according to the present invention. In any of the above-mentioned pressure-resistant synthetic resin pipes A and A ′, a hard synthetic resin outer shell is shown. The outward-facing locking piece 3 and the inward-locking piece 4 provided on the hard coating piece 2a forming the hook 2 are formed in a hook shape. In this pressure-resistant synthetic resin tube A ″, The outward locking piece 3A and the inward locking piece 4A provided on the hard coating piece 2a are formed from protrusions having a rectangular cross section, and are adjacent when the pressure-resistant synthetic resin tube A '' is curved. The outward covering pieces 3A and the inwardly engaging pieces 4A of the hard coating pieces 2a, 2a are configured to be engaged with each other in a joined state. Since other configurations are the same as those of the above-described embodiment, the same portions are denoted by the same reference numerals, and detailed description thereof is omitted.

  In any of the above-mentioned pressure-resistant synthetic resin pipes A, A ′, A ″, the inner and outer peripheral surfaces of the hard covering piece 2a are formed on flat surfaces parallel to the length direction of the pipe. It may be curved in a gently convex arc shape from the side toward the tip, and by forming in this way, when the pressure-resistant synthetic resin tube is curved, the adjacent hard coating piece portions 2a, 2a The outward locking pieces 3 or 3A and the inward locking pieces 4 or 4A can be smoothly and reliably engaged. Further, in the present invention, the pressure-resistant synthetic resin pipes A, A ′, A ″ are formed as short pipes, and short tube-shaped joint ports are integrally provided at both ends thereof so as to face opposite ends such as straight hard pipes. You may form in the pressure-resistant synthetic resin tube for a connection which connects between.

FIG. 3 is a simplified side view of a part of the pressure-resistant synthetic resin tube A. The enlarged side view which cut the part. The side view of a part which sectioned a part of the state bent. The simplified side view for demonstrating a manufacturing method. The side view which carried out the cross section of a part which shows another embodiment of this invention. The side view which carried out the cross section of a part which shows another embodiment of this invention.

Explanation of symbols

A Pressure-resistant synthetic resin tube 1 Soft synthetic resin tube 2 Hard synthetic resin shell
2a Hard coating piece 3 Outward locking piece 4 Inward locking piece 5 Hard spiral ridge

Claims (3)

  A hard synthetic resin strip having a certain width on the outer peripheral surface of a soft synthetic resin pipe is spirally wound at a constant pitch shorter than the width of the hard synthetic resin strip, and the inner peripheral surface of one end thereof is soft. The tip of the hard-covered piece portion made of the belt-shaped material portion wound next is wound on the base portion of the hard-covered piece portion made of the belt-shaped material portion wound one time before being fixed to the outer peripheral surface of the synthetic resin pipe. In a pressure-resistant synthetic resin pipe that forms a hard synthetic resin outer shell that is slidably stacked in the length direction of the pipe to cover the entire outer surface of the soft synthetic resin pipe, When the outer periphery of the base end and the inner periphery of the base end facing the tip end are provided with an outward locking piece and an inward locking piece, respectively, and the tube is curved The other hard coating on the outward locking piece of one hard coating piece in the hard coating piece adjacent to Withstand synthetic resin pipe having flexibility, characterized in that the inward locking piece parts and lockably configuration.   2. The flexible pressure-resistant synthetic resin pipe according to claim 1, wherein an inward locking piece is provided at a tip of the hard coating piece.   The outward locking piece is formed in a hook shape that opens toward the distal end side of the hard coating piece portion, while the inward locking piece opens toward the proximal end side of the hard coating piece portion. The flexible pressure-resistant synthetic resin pipe according to claim 1, wherein the flexible pressure-resistant synthetic resin pipe is formed into a hook shape.

Images