JP4705799B2 - Inner core for cold shrink tube - Google Patents

Description

The present invention relates to a normal temperature shrinkage inner core tube Ru support jig der for supporting the cold shrink tube diameter expansion state.

  The cold shrink tube is used, for example, for covering a terminal of a power cable or a connecting portion when connecting the power cable, and exhibits an electric field relaxation effect and an insulating effect.

  This normal temperature shrinkable tube is made of a rubber elastic body, for example, a cylindrical body made of a material such as silicone rubber, ethylene propylene diene monomer (EPDM, EPM), and is in a contracted state at normal temperature. . When using this cold-shrinkable tube, it is necessary to spread the cold-shrinkable tube in advance. In order to maintain this expanded state (hereinafter referred to as “expanded diameter”), The inner core is used. As an inner core, for example, as shown in Patent Documents 1 and 2, there is a structure in which a slit or a groove is formed in the inner core body so that the inner core body can be easily unraveled. A spiral core is used which is formed in a cylindrical shape by spirally winding a wire.

  Conventionally, the spiral core is made of a synthetic resin, and is formed by forming a solid ribbon processed into a strip or string having a strength not to be crushed by a cold shrink tube into a spiral cylindrical body. By covering this with an expanded cold shrink tube, the cold shrink tube can maintain a predetermined diameter.

  The cold shrink tube supported by the spiral core in this way is the place where the cold shrink tube is to be attached, and the ribbon at one end of the spiral core is guided to the other end and the spiral core is removed to the other end to shrink. Cover the object.

  FIG. 9 shows a cross-sectional view of an example of a ribbon constituting a conventional spiral core. The ribbon 1 shown in FIG. 9 has saddle-shaped fitting portions 2 that can be fitted to each other on both sides, and is cast by an extruder using a synthetic resin. FIG. 10 is a partial cross-sectional view of a conventional spiral core 10.

  The cast ribbon 1 shown in FIG. 9 is wound around a member such as a mandrel for winding up in a coil shape (spiral shape), and the connecting portions 4 facing each other in the adjacent ribbons 1 are fitted together. (See FIG. 10), the cylindrical spiral core 10 is formed.

  That is, the conventional spiral core constituted by the ribbons shown in FIGS. 9 and 10 is made of a polymer material such as, for example, polypropylene (Polypropylene) resin, and is molded by an extruder using an expensive die and nipple. , Manually wrapped around a mandrel. The conventional spiral core is preferably made of a synthetic resin that does not soften at the ambient temperature and has a strength corresponding to the shrinkage force of the normal temperature shrinkable tube when the expanded cold shrinkable tube is covered.

  In addition, in a spiral core made of a ribbon having a configuration that does not have a fitting portion or the like at both ends, for example, as shown in Patent Document 3, it is covered on a ribbon wound in a coil shape so that adjacent ribbons are not separated from each other. A structure is used in which the cover and the coiled ribbon are integrated and fixed.

In general, a ribbon made of a polymer material is formed to be narrow and thin in order to facilitate extrusion during extrusion. In addition, since the ribbon to be formed is thin, it can be cooled and solidified in a short time after being softened by overheating and extrusion, and the influence of shrinkage due to cooling is small.
JP 2002-271970 A Japanese Utility Model Publication No. 7-2692 JP-A-9-141742

  In recent years, the size of the cold shrink tube has been increased, and in order to support this, the strength of the conventional spiral core itself must be increased. Therefore, it is necessary to increase the thickness and width of the ribbon forming the spiral core to increase the size.

  However, a ribbon using synthetic resin is deformed by shrinkage after extrusion. More specifically, in ribbon molding, a ribbon molded body extruded in a high temperature state has a temperature difference between the surface and the inside of the ribbon that is proportional to the thickness until it is cooled to room temperature. In addition, in a ribbon having a complicated surface shape such as a ribbon having a fitting portion, it is difficult to cool the entire ribbon uniformly, and irregular shrinkage occurs due to uneven cooling in the ribbon itself.

  FIG. 11 is a cross-sectional view showing a contracted state after forming a thick ribbon. In the conventional ribbon 1 shown in FIG. 11 (a), the material 1 ′ extruded with the same resin and thick is cooled and solidified from the surface 1a. However, in the thick-walled interior 1b, it is fluid even if the surface 1a is hardened. The temperature becomes high. Further, the portion 2 ′ that becomes the fitting portion 2 (see FIG. 9) is thinner than the thick-walled inner portion 1 b and is quickly cooled and solidified.

  That is, the surrounding solid surface 1a is maintained in a state close to the extruded shape, but is dragged by the internal resin that shrinks as the thick-walled interior 1b cools, as shown in FIG. In the material 1 ′, a recess 3 is formed. Further, the corner portion 5 has a large surface area, and only the surface layer is quickly cooled and solidified, so that the projection portion 6 is formed. Furthermore, the fitting part 2 is forced to change the shape by deforming the corner part 5 from the initial shape, and in such a shape, when the fitting part 2 is wound spirally, The ribbons 1 cannot be firmly fixed to each other, and the target spiral core cannot be formed.

  In order to solve this problem, conventionally, when extruding, a method of casting into a shape that allows for the shrinkage and finishing to a predetermined dimensional shape while devising a cooling method has been adopted. A ribbon with a good shape cannot be made.

  For this reason, the problem is that the target ribbon is manufactured by repeating cut-and-dry such as cutting the shape of the die while observing the state of extrusion molding of the resin, which takes time and costs. was there.

The present invention has been made in view of the above, regardless of the size of the cold shrink tube covers, and has a sufficient response can strength to the shrinkage force, the In'nako A for cold shrinkable tube can be accurately manufactured easily The purpose is to provide.

An inner core for a cold shrinkable tube of the present invention comprises a ribbon main body and a fitting portion and a fitted portion formed on both side surfaces of the ribbon main body, and a flexible string-like or belt-like ribbon. It is formed into a cylindrical body by spirally winding it to a predetermined diameter, and is provided in a room temperature shrinkable tube made of a rubber elastic body. An inner core for a cold-shrinkable tube that withstands and maintains an expanded diameter, wherein the fitting part and the fitted part have a saddle shape that can be fitted to each other, and the fitting part is connected to the fitted part the tubular body is axially fitted removably in a direction intersecting engaged in while being restricted from moving in the direction adjacent said ribbon Te, the central portion in said ribbon body, the axis of the ribbon body have a same axis, and It formed in the previous SL higher melting point than the ribbon body of the material material, a configuration in which the core material is disposed.

  According to this configuration, since the ribbon body has the core material covered with the ribbon body, the thick portion of the ribbon body becomes thinner by the amount of the core material disposed inside. Therefore, when manufacturing a ribbon main body, especially when manufacturing by extrusion molding, the shrinkage | contraction produced by solidification of the raw material of the fuse | melted ribbon main body can be reduced, and it can shape | mold with a dimensional accuracy.

  As a result, a wide and thick inner core ribbon can be manufactured with high accuracy. Therefore, even when the inner core itself is enlarged with the increase in the size of the normal temperature shrinkable tube that covers the inner core, the inner core ribbon is easily manufactured to be wide and thick and assembled into a cylindrical shape. Thus, an inner core having a strength that can sufficiently cope with the contraction force can be assembled.

  As described above, according to the present invention, it is possible to assemble an inner core that can be sufficiently formed and can be easily formed with high accuracy regardless of the size of the cold shrinkable tube to be covered.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an overall view showing a structure of a spiral core 200 for a cold-shrinkable tube as an example of an inner core for a cold-shrinkable tube according to an embodiment of the present invention. A spiral core 200 for cold-shrinkable tube shown in FIG. 1 is formed into a tubular shape by spirally winding a long string-like or belt-like ribbon 100, and adjacent portions 101 of the spirally wound ribbon 100 are joined together. It becomes by doing.

  In this spiral core 200, the leading end portion 102 of the ribbon 100 that is wound up in a spiral shape to form a cylindrical body has a predetermined position (here, one end portion 103 of the cylindrical body) that forms one opening of the cylindrical body. ) And passed through the inside of the cylindrical body. And the front-end | tip part 102 is guide | induced to the other end part 104 side which forms the other opening part of a cylindrical body, and is derived | led-out outside from the other end part 104 of a cylindrical body. A portion led out from the other end 104 of the cylindrical body including the tip 102 is a tail of the spiral core 200.

  The spiral core 200 can be disassembled and removed by pulling the tail toward the other end 104 (in the direction of arrow P), that is, pulling the ribbon 100 toward the other end 104.

  FIG. 2 is a cross-sectional view of the ribbon 100 that forms the spiral core 200 for a cold-shrinkable tube shown in FIG.

  The ribbon 100 shown in FIG. 2 is a long, flexible material that is required to have a strength that can withstand the force of the normal temperature shrinkable tube that is to be shrunk, and that is not easily softened at ambient temperature. It is comprised by the material which can maintain the diameter expansion state.

  Ribbons 100 are formed on a ribbon body 110 to be extruded, a core member 120 covered with the ribbon body 110, and both sides of the ribbon body 110, and can be fitted to each other. Part 130 and fitted part 140 are provided.

  The ribbon main body 110, the fitting portion 130, and the fitted portion 140 are made of extruded synthetic resin, and here are made of colorless and transparent polypropylene (PolyPropylene) resin. In addition, as a material of the ribbon 100, a polyethylene terephthalate (PolyEthylene Terephthalate) resin may be used, or a mixed material with other resin (for example, polyethylene) etc. which is easy to mix with a polypropylene may be used.

  In particular, a polypropylene resin is light because of its low density, has a high softening temperature, is environmentally friendly, has high tensile strength, bending strength and rigidity, and has good bending fatigue resistance. Furthermore, the polypropylene resin is excellent in processability, has good transparency and surface gloss, has a small molding shrinkage ratio, and has a high appearance and dimensional accuracy.

  Here, the ribbon main body 110 is formed in a substantially rectangular cross section, and the front and back surfaces 111 and 112 of the ribbon main body, which are the front and back surfaces of the ribbon 100, are arranged in parallel. Further, the both sides 113 and 114 of the ribbon main body 110 are provided with a fitting portion 130 and a fitted portion 140 that are fitted to each other.

  The fitting part 130 and the fitted part 140 are shaped to fit each other, and here, each has a saddle shape, and is point-symmetric about the axis of the ribbon 100 on both sides of the ribbon body 110. It is formed without. The fitting portion 130 is restricted from moving in the adjacent direction of the ribbon 100 (string-like body or belt-like body) with respect to the fitting portion 140 and is the axis of the tubular body (here, the spiral core 200 itself). Removably fitted in a direction crossing the direction.

  By fitting the fitting part 130 and the to-be-fitted part 140 configured in this way, the ribbons 100 wound in a spiral shape and adjacent in the axial direction are adjacent to each other at the adjacent part 101 (see FIG. 1). Be joined.

  A core member 120 having the same axis as the axis of the ribbon main body 110 is disposed at a substantially central portion of the ribbon main body 110.

  Here, the core material 120 is made of an extruded synthetic resin and has a solid cylindrical shape having flexibility, and is formed before the ribbon body 110 is extruded. As a material of the core material 120, a resin equivalent to the ribbon main body, for example, colorless and transparent polypropylene (PolyPropylene) resin, polyethylene terephthalate (PolyEthylene Terephthalate) resin, polypropylene, and other resins that are easily mixed with the polypropylene (for example, polyethylene ( Polyethylene)) and the like. Further, as the core member 120, it is preferable to use a crosslinked structure polymer material such as a heat resistant elastomer (Elastomer) or rubber in order to suppress deformation due to shrinkage of the material of the ribbon main body 110.

  Next, the manufacturing method of the ribbon 100 for spiral cores used for a normal temperature shrinkable tube is demonstrated.

  FIG. 3 is a diagram showing the main steps for explaining the production of the spiral core ribbon 100 as the inner core ribbon according to the present invention. 4 is a diagram for explaining the behavior in the cross head 310 shown in FIG. 3. FIG. 4 (a) is a schematic diagram for explaining the behavior of the cross head 310 viewed from the A direction, and FIG. FIG.

  As shown in FIG. 3, the ribbon 100 (see FIGS. 1 and 2) is manufactured from a drum 380 around which a core material 120 to be preformed is wound (in the direction of arrow S), and the crosshead 310 of the extrusion device 330. It is manufactured by covering with a material forming a ribbon shape when passing through.

  Here, when the ribbon 100 is manufactured, an extrusion device 330 including a cross head 310 that covers the ribbon main body 110 on the core material 120 to be inserted, a sizing device 350, a cooling tank 370, and the like are mainly used. In FIG. 3, the sizing device 350 and the cooling rod 370 are schematically illustrated.

  The extrusion device 330 covers the core material 120 guided by the cross head 310 with the material of the ribbon main body 110 and sends it to the sizing device 350 and the cooling tank 370. In addition, the cross head 310 which coat | covers the core material 120 with the raw material of the ribbon main body 110 coat | covers the core material 120 with the ribbon main body 110, and shape | molds the fitting part 130 and the to-be-fitted part 140 with a raw material. In the following, only the molding of the ribbon main body 110 will be described on the assumption that when the core member 120 is covered with the ribbon main body 110 during molding, the fitting portion 130 and the fitted portion 140 are also formed into a predetermined shape. The description of the fitting part 130 and the fitted part 140 is omitted.

  The extrusion device 330 includes a hopper 331 (see FIG. 3) into which the raw material pellets of the ribbon main body 110 are charged, a heating device (not shown) for softening the raw material pellets to be loaded into the hopper 331, and the softened material. And a screw 332 (see FIG. 4) and a cylinder 333 (see FIG. 4) for continuously performing extrusion casting.

  In the extrusion device 330, the raw material pellets put into the hopper 331 are heated and melt-kneaded, and the molten material is discharged from the discharge port 334 (see FIG. 4) and sent to the cross head 310.

  The cross head 310 covers and extrudes the surface of the core member 120 to be inserted with a material fed through the discharge port 334.

  The extrusion shaft of the extrusion device 330 that pushes the material into the crosshead 310 through the discharge port 334 is in a direction in which the core material 120 is inserted, that is, in a direction orthogonal to the moving direction of the core material 120 (arrow C direction). Has been placed.

  Then, as shown in FIG. 4A, the cross head 310 has a cylindrical interior that narrows from the moving direction of the core material 120 (arrow C direction) toward the extrusion port side that extrudes the core material 120. Have a space. This internal space constitutes a material guide 311 that guides the material fed from the discharge port 334 to the periphery of the core material 120. A ribbon-shaped die 312 is connected to and attached to the extrusion port of the material guide 311.

  As described above, in the cross head 310, the core material is inserted in a direction orthogonal to the extrusion axis of the material in the extrusion device 330. For this reason, in the cross head 310, the material fed from the discharge port is rotated around the core member 120 on the circumference while changing the direction at a right angle, and is molded into an irregular shape by the die 312. It is extruded from 314 in a state where the surface of the core member 120 is covered. The ribbon that has been extruded from the molding port 314 and has yet to be solidified to become the ribbon 100, that is, the ribbon in which the core material 120 is covered with the ribbon body 110 is hereinafter referred to as a “ribbon molded body”.

  The sizing device 350 is extruded from the cross head 310 in order to increase the dimensional accuracy of extrusion molding, and shapes the outer surface of the ribbon molded body in close contact with the sizing mold.

  The cooling tank 370 prevents deformation of the ribbon molded body, and cools and solidifies the ribbon molded body to room temperature.

  With reference to FIG.3 and FIG.4, the manufacturing method of the ribbon for spiral cores using the crosshead 310 and each apparatus 330,350,370 is demonstrated.

  The core material 120 to be molded in advance is wound around the drum 380, and the core material 120 is drawn out from the drum 380 around which the core material 120 is wound and inserted into the cross head 310 of the extrusion device 330.

  In the extruding device 330, the raw material pellets are supplied to the hopper 331, and the raw material pellets are heated and melted and kneaded by a heating device, a screw 332, a cylinder 333, etc., and are fed into the crosshead 310 from the discharge port 334.

  As shown in FIG. 4A, a melted material pallet (hereinafter referred to as “melted material”) that flows vertically from the discharge port 334 toward the paper surface flows along the material guide 311 in the crosshead 310. As a result, melted material flows D and E are generated.

  Moreover, the raw material guide part 311 is formed so that the raw material sent in may cover the core material 120, and the melted raw material sent into the raw material guide part 311 is the raw material guide part 311 as shown in FIG. Flows F and G are made to satisfy Then, as shown in the flows F and G, the molten material fills the material guide part 311 while being bent, and is disposed around the core material 120. Then, the melted material is coated on the surface of the core material 120 located at the center of the molding port 314 through the molding port 314 for extruding the material in the form of a ribbon provided on the die 312.

  The melted material covering the core material 120 is heated and softened after being extruded, and is cured as it is cooled. However, since the surface is deformed due to the shrinkage, it is guided to the sizing device 350 in order to prevent this and to finish the surface shape with high accuracy.

  That is, in order to form a ribbon molded body extruded from the die 312 of the crosshead 310 into a ribbon shape with high accuracy, the shape of the casting material surface in the ribbon molded body is adjusted by the sizing device 350 and the whole is cooled by the cooling tank 370. Finish by doing. The finished ribbon 100 is wound up by a drum 390.

  The ribbon 100 molded in this way is wound up spirally around a predetermined winding core such as a mandrel (not shown) so as to be a cylindrical body having an appropriate diameter and length, thereby shrinking at room temperature. The spiral core 200 for tubes is assembled.

  In the spiral core 200 wound up, the ribbons 100 adjacent in the axial direction are joined together by fitting the fitting part 130 and the fitting part 140 facing each other. For example, fitting is performed so that the fitted portion 140 is on the one end portion 103 (see FIG. 1) side and the fitting portion 130 is on the other end portion 104 side (see FIG. 1).

  In the cylindrical body assembled by winding up the ribbon 100 in this manner, the ribbon is adjacent by pulling the ribbon 100 on the one end 103 side of the cylindrical body in the other end direction (P direction in FIG. 1). The ribbon 100 comes off while being twisted.

  In the present embodiment, the shapes of the fitting portion 130 and the fitted portion 140 are point-symmetric with respect to the cross-sectional center of the ribbon 100. For this reason, the to-be-fitted part 140 may be located in the other end part 104 side, the fitting part 130 may be located in the one end part 103 side, and a cylindrical body may be assembled. When the ribbon 100 is wound, the outer surface of the spiral core 200 is maintained in a firmly and firmly fitted state in which the overlapping of the fitting portion 130 and the fitting portion 140 is smooth.

  Further, when the assembled spiral core 200 is disassembled by pulling out the ribbon 100, when the drawing of the ribbon 100 is stopped, the engagement state of the fitting portion 130 and the fitted portion 140 is maintained, and the spiral core 200 is retained. The self-running at the time of pulling out in the dismantling of can be prevented.

  As described above, the spiral core ribbon 100 according to the present embodiment includes the core member 120 covered with the ribbon body 110 inside the ribbon body 110. For this reason, in the ribbon 100, the thick part of the ribbon main body 110 can be made thin as much as the core member 120 is disposed inside. That is, when the ribbon 100 is formed by coating the core material 120 with a material to be the ribbon main body 110 which is a melted synthetic resin, the shrinkage caused by the cooling of the ribbon main body 110 covering the core material 120 occurs. Even when doing so, deformation due to shrinkage is difficult to occur.

  When a large-size cold-shrinkable tube is manufactured, the cold-shrinkable tube itself is thick, and if it becomes a long shape, the shrinkage force increases. Therefore, a spiral core is required to ensure the strength to maintain the expanded state of such a cold-shrinkable tube. 200 has a large diameter and a long length. Accordingly, the ribbon 100 constituting the spiral core 200 is required to have a wide and thick structure so as to have a strength capable of withstanding the contraction force of the normal temperature contraction tube.

  On the other hand, according to the present embodiment, since the ribbon 100 has a double or more structure of the ribbon main body 110 and the core member 120, even when the ribbon 100 is increased in size, a wide and thick casting is performed. It is possible to absorb distortion caused by thermal contraction during the molding of the ribbon 100 and improve the shape accuracy.

  Thus, according to the present embodiment, even if a synthetic resin, here, polypropylene is used as the material of the ribbon 100, the expanded state can be maintained regardless of the size of the normal temperature shrinkable tube to be covered. At the same time, it can be easily formed with high accuracy.

  Further, according to the present embodiment, unlike the conventional case, when forming a ribbon, there is no need to change the shape of the die empirically to perform extrusion work by trial and error in order to absorb the shrinkage after forming. Therefore, it is possible to easily extrude the profile with high accuracy.

  Furthermore, unlike the conventional case where the extrusion molding is performed while adjusting the shape of the ribbon to be molded, the ribbon extrusion speed can be improved, and the cost can be reduced.

  Furthermore, in the configuration of the ribbon 100, the ribbon shape can be changed by adjusting the thickness of the material to be the ribbon main body 110 at the time of molding without changing the core material 120. Thereby, when manufacturing a plurality of types of ribbons having different sizes, a cost merit can be achieved by sharing the core material without preparing many core materials corresponding to the ribbons.

  Further, the core material 120 is made of a material having a melting point higher than that of a material as a main material of the spiral core that forms the ribbon main body 110 that covers the core material 120. That is, the core material 120 is formed of a material such as a heat resistant elastomer or rubber whose durability is improved by crosslinking. Thereby, the deformation | transformation by the shrinkage which arises in the case of shaping | molding can be reduced.

  Further, by using the same material as the material of the ribbon main body 110 as the core material, it is possible to fuse both at the time of heat extrusion, and the core material 120 inside the ribbon 100 is at a temperature close to room temperature during cooling. Since the shrinkage at the time of cooling is small, the ribbon 100 with high casting accuracy can be easily manufactured.

  In the embodiment described above, the ribbon 100 is formed by covering the core material 120 formed in advance with the material of the ribbon main body 110. However, the present invention is not limited thereto, and the hollow ribbon main body 110 is formed. After forming, the core material 120 may be formed by being inserted into the ribbon main body.

  Here, the core material 120 in the spiral core ribbon 100 is a solid columnar shape, but any shape can be used as long as the ribbon body 110 is covered with the ribbon body 110. There may be. For example, it is conceivable to configure the core member 120 in a cylindrical shape, a rectangular tube shape, a prismatic shape, a bellows tubular shape, a coil shape, a spring shape, or the like.

  Below, the ribbon which has the core material 120 of various shapes is each shown by sectional drawing as a modification. Each modification shown below has the same basic configuration as the ribbon 100 corresponding to the first embodiment shown in FIG. 2, and the same components are denoted by the same reference numerals. Description is omitted.

<Modification>
FIG. 5 is a diagram showing modifications 1 to 3 of the inner core ribbon according to the embodiment of the present invention.

  The ribbon 400 as the first modification shown in FIG. 5A has basically the same configuration as that of the ribbon 100, and the ribbon 400 is not limited to the core material 120 disposed inside the ribbon main body 110. The longitudinal direction of the fitting portion 430 and the fitted portion 440 inside the fitting portion 430 and the fitted portion 440 provided in the same shape as the fitting portion 130 and the fitted portion 140 with respect to the ribbon main body 110. It has the core material 220 for fitting parts extended along.

  Since the ribbon 400 has the fitting portion core material 220, the core material 120 and the fitting portion core material 220 are sent to the cross head in a process of being manufactured in substantially the same manner as the ribbon 100. The core material 120 and the core material 220 for the fitting portion are covered with the molten material of the ribbon main body 110, the fitting portion 430, and the fitted portion 440. In the ribbon 400 delivered from the cross head, the thick portion of the ribbon main body 110 is thinned by the core material 120, and the fitting portion 430 and the fitted portion 440 having corners are formed by the fitting portion core material 220. The thick part can also be made thin. When solidifying after molding, the fitting part 430 and the fitting part 440 are less likely to shrink, and in addition to the ribbon body 110, the cornered fitting part 430 and the fitted part 440 are formed with higher dimensional accuracy. can do.

  The ribbon 500 as the second modification shown in FIG. 5B is a solid, substantially rectangular core material instead of the columnar core material 120 arranged in the ribbon main body 110 in the configuration of the ribbon 100. This is a configuration in place of 520.

  That is, the ribbon 500 is provided with a core material 520 that is covered with the ribbon body 110 inside the ribbon body 110. Here, the ribbon main body 110 is formed to have a substantially rectangular cross section, and the front and back surfaces 111 and 112 of the ribbon main body 110 which are the front and back surfaces of the ribbon 500 are arranged in parallel. Further, the both sides 113 and 114 of the ribbon main body 110 are provided with a fitting portion 130 and a fitted portion 140 that are fitted to each other.

  The core material 520 is formed in a substantially rectangular shape in cross section, and is arranged in the center of the axial center portion of the ribbon main body 110, in other words, the thick portion of the ribbon main body, and extends along the longitudinal direction of the ribbon main body 110. With this core material 520, in the ribbon main body 110, the thick portions 110 a and 110 b on the front and back surfaces 111 and 112 side and the side surfaces 113 and 114 side surrounding the core material 520 have substantially uniform thicknesses.

  According to this configuration, the core 520 is formed in a prismatic shape, that is, in a rectangular cross section, unlike the cylindrical one, and the thick portions 110a and 110b of the ribbon main body 110 are each formed to have a substantially uniform thickness. When the core body 520 is covered with the ribbon main body 110 by extrusion molding, the shrinkage of the material that becomes the ribbon main body 110 can be reduced, and deformation of the formed ribbon 500 can be prevented.

  In the configuration of the ribbon 500, a plurality of core members 520 disposed in the ribbon main body 110 may be disposed. An example of this is shown in FIG.

  A ribbon 600 as a third modification shown in FIG. 5C is provided with a fitting portion 130 and a fitted portion 140 on both side surfaces of a substantially rectangular ribbon main body 610 having three core members 520 therein. It is comprised by.

  In the ribbon 600, since a plurality of core members 520 are arranged inside the ribbon main body 610, the ribbon 600 itself is long in the width direction.

  According to this configuration, even if it is necessary to enlarge the spiral core itself as the normal temperature shrinkable tube covering the spiral core increases, the ribbon 600 can easily cope with it. That is, since the width of the ribbon 600 itself, which is the axial length of the cylindrical body when rolled up, is long, the fitting portion 130 and the fitted portion generated when the ribbon 600 is wound up spirally to assemble the spiral core. 140 fitting work can be reduced.

  FIG. 6 is a view showing a fourth modification of the inner core ribbon according to the embodiment of the present invention. A ribbon 700 as a fourth modification shown in FIG. 6 is provided with a cylindrical core material 720 in place of the solid cylindrical core material 120 in the configuration of the ribbon 100 in the first embodiment. .

  In the ribbon 700, the cylindrical core material 720 can efficiently cool the material to be the ribbon main body 110 that covers the core material 720 by passing the coolant through the inside after the ribbon molded body is formed. . Therefore, the deformation due to shrinkage that occurs when the material solidifies, that is, the deformation of the ribbon main body 110, more specifically, the entire deformation of the ribbon 700 itself can be efficiently prevented, and the ribbon 700 itself can be produced. It is possible to improve the performance.

  In addition, when a cylindrical core material is arranged in the ribbon main body 110, the shape of the core material is not limited to this, and any shape can be used as long as it reduces the shrinkage of the ribbon main body that covers the core material after molding. You may be comprised in such a shape.

  Moreover, when forming the core material in a ribbon main body into a cylinder shape, it may bridge | crosslink from the core material inside with respect to the ribbon main body which coat | covers a core material, and you may make it change resin performance.

  FIG. 7 is a diagram illustrating modifications 5 and 6 of the embodiment in the case where the core member 120 is a cylindrical member in the ribbon 100 of the first embodiment.

  The ribbon 800 as the modified example 5 shown in FIG. 7A is substantially the same in basic configuration as the ribbon 100, and has a rectangular tube shape inside the ribbon main body 810 configured substantially the same as the ribbon main body 110. A core member 820 having a rectangular cross-section is disposed.

  With the core material 820, the thick portions 110a and 110b on the front and back surfaces 111 and 112 side and the side surfaces 113 and 114 side surrounding the core material 820 have a substantially uniform thickness in the ribbon body 810.

  According to this configuration, the core material 820 is formed in a rectangular tube shape, and the thick portions 110a and 110b of the ribbon main body 810 have substantially uniform thicknesses. Therefore, the core 820 is formed by the ribbon main body 810 by extrusion molding. Can be reduced, and the deformation of the ribbon 800 to be formed can be prevented.

  In addition, the ribbon body 810 can be more efficiently cooled by passing the coolant through the ribbon 800 to be molded into the core member 820, so that productivity can be improved.

  The ribbon 800a as the modified example 6 shown in FIG. 7B is the same as the ribbon 800 as the modified example 5 except that the hollow portion inside the core member is replaced with the rectangular core member 820 in the cross section of the hollow portion inside the core member. This is a cylindrical core member 830 having an inner peripheral surface 802 that has a circular cross section (may be elliptical). Further, unlike the core material 820, the core material 830 has a corner (protruding corner) 830a in the cross section of the core material 830 that contacts the ribbon main body 810 in a cross-sectional view.

  In the ribbon 800a, since the cross-sectional shape of the hollow portion in the cylindrical core member 830 is circular, the strength of the ribbon 800a is improved as compared with the ribbon 800. The basic function and effect of the ribbon 800a is the same as that of the ribbon 800 having the same configuration, and the description thereof is omitted.

  In each of the modified examples 4 to 6, the cylindrical core member may be formed in a shape that can be expanded and contracted in the longitudinal direction, for example, a bellows tubular shape, or a peripheral wall having a corrugated longitudinal section.

  FIG. 8 is a view showing a modification 8 of the inner core ribbon according to the embodiment of the present invention. A ribbon 900 as a modified example 7 shown in FIG. 8 has a bellows tubular core 920 inside a ribbon main body 910 formed in the same manner as the ribbon main body 110.

  As described above, the bellows-shaped tubular core material 920 can prevent the formed ribbon 900 from becoming difficult to bend in addition to the above-described effect, and can be easily wound up in a spiral shape to facilitate the assembly of the spiral core. it can. That is, it is possible to improve handling when the ribbon 900 is assembled into a cylindrical inner core, here, a spiral core, and further improve the assembly. That is, making the core material 920 bellows in this way is effective when the core material itself is made soft, or when heat resistance is required and the hardness of the material selected as the core material is increased. Yes, the flexibility of the ribbon itself having the core material 920 can be ensured. Moreover, you may comprise a core material in the spring-like body which wound up the linear member helically. The core material with this configuration is extendable in the axial direction, and a ribbon having this core material can obtain the same effects as the ribbon 900.

  In addition, although the ribbon 100 in each said embodiment and modification shall be formed by coat | covering the core material 120 shape | molded previously with the raw material of the ribbon main body 110, it is not restricted to this, A hollow ribbon After the main body 110 is molded, the core material 120 may be inserted into the ribbon main body.

  Further, in each of the ribbons 100, 400, 500, 600, 700, 800, 800a, and 900 shown in the present embodiment, a double structure is formed by the main body and the core material, but the structure is not limited to this and is a double structure or more. Also good. For example, the ribbon main body that covers the core material may be configured to cover the core material with multiple layers.

  In the present embodiment, the ribbons 100, 400, 500, 600, 700, 800, 800a, and 900 are spirally wound to fit the fitting portion 130 and the fitted portion 140 between adjacent ribbons. The spiral core is assembled as an inner core that is a cylindrical body by combining, but the present invention is not limited to this. In other words, as long as each of the ribbons 100, 400, 500, 600, 700, 800, 800 a, and 900 having the above configuration is used, a cylindrical cold shrinkable tube inner core may be formed.

  Furthermore, the ribbon 400 as the modified example 1 includes a fitting portion in the fitting portion 430 and the fitted portion 440 provided in the same shape as the fitting portion 130 and the fitted portion 140 with respect to the ribbon main body 110. The core part 220 for fitting parts extended along the longitudinal direction of 430,440 shall have.

  The configuration in which the fitting portion core material 220 is provided in the fitting portion 430 and the fitted portion 440 as described above may be applied to the ribbons 500, 600, 700, 800, 800a, and 900 shown in other modified examples. Good. In this case, the function and effect are the same as those in the ribbon 400, and a description thereof will be omitted.

  An inner core ribbon according to a first aspect of the present invention is an inner core ribbon that forms a cylindrical inner core that is covered by an expanded cold-shrinkable tube. A configuration having a core material to be coated is adopted.

  According to this configuration, since the ribbon body has the core material covered with the ribbon body, the thick portion of the ribbon body becomes thinner by the amount of the core material disposed inside. Therefore, when forming the ribbon main body, particularly when extrusion molding is performed, shrinkage caused by solidification of the material of the melted ribbon main body can be reduced, and the ribbon main body can be formed with high dimensional accuracy. As a result, a wide and thick inner core ribbon can be manufactured with high accuracy. Therefore, even when the inner core itself is enlarged with the increase in the size of the normal temperature shrinkable tube that covers the inner core, the inner core ribbon is easily manufactured to be wide and thick and assembled into a cylindrical shape. Thus, an inner core having a strength that can sufficiently cope with the contraction force can be obtained.

  The ribbon for an inner core according to the second aspect of the present invention adopts a configuration in which the core material is cylindrical in the above configuration.

  According to this configuration, since the core material is cylindrical, the material to be the ribbon body covering the core material can be efficiently cooled by passing the coolant through the core material. Therefore, the deformation due to the contraction of the ribbon main body can be efficiently prevented, and the productivity of the ribbon for the inner core can be improved.

  The ribbon for the inner core according to the third aspect of the present invention has a configuration in which, in the above configuration, the core material is an accordion tube.

  According to this structure, since the core material of the ribbon for inner cores is a bellows tubular shape, the core material itself can be expanded-contracted in a longitudinal direction, and has flexibility. In other words, even when the core material itself is soft, or when heat resistance is required and the hardness of the material selected as the core material is increased, the flexibility of the ribbon itself having the core material is ensured. can do. Therefore, it is possible to prevent the inner core ribbon itself having the core material from becoming difficult to bend, and it is possible to improve handling when the ribbon is assembled into the cylindrical inner core. Specifically, the inner core ribbon can be easily wound up in a spiral shape, and the spiral core can be easily assembled.

  The ribbon for an inner core according to a fourth aspect of the present invention has a configuration in which the core is a spring-like body in which a linear member is spirally wound.

  According to this configuration, since the core material of the ribbon for the inner core is a spring-like body, the core material itself can be expanded and contracted in the longitudinal direction, and has flexibility. In other words, even when the core material itself is soft, or when heat resistance is required and the hardness of the material selected as the core material is increased, the flexibility of the ribbon itself having the core material is ensured. can do. Therefore, it is possible to prevent the inner core ribbon itself having the core material from becoming difficult to bend, and it is possible to improve handling when the ribbon is assembled into the cylindrical inner core. Specifically, the inner core ribbon can be easily wound up in a spiral shape, and the spiral core can be easily assembled.

  The inner core for a cold-shrinkable tube according to the fifth aspect of the present invention adopts a configuration formed into a cylindrical shape by winding the inner core ribbon having the above-described configuration in a spiral shape.

  According to this configuration, since the inner core ribbon having the core material covered by the ribbon body is spirally wound inside the ribbon body, the ribbon body is formed into a cylindrical shape. In addition, it has sufficient strength to cope with the contraction force and can be easily manufactured with high accuracy.

  The ribbon for an inner core according to the present invention can assemble an inner core that can be sufficiently formed with high precision and can be easily assembled regardless of the size of a normal temperature shrinkable tube that is covered, and can be used for connecting a power cable. It is useful as a constituent of the support jig for the cold shrink tube used.

The whole figure which shows the structure of the spiral core for cold shrinkable tubes as an example of the inner core for cold shrinkable tubes which concerns on one embodiment of this invention Sectional view of the ribbon forming the spiral core for the cold-shrinkable tube shown in FIG. The figure which shows the main processes for demonstrating manufacture of the ribbon for spiral cores as the ribbon for inner cores which concerns on this invention The figure explaining the behavior in the crosshead shown in FIG. The figure which shows the modification of the ribbon for inner cores based on one embodiment of this invention The figure which shows the modification of the ribbon for inner cores based on one embodiment of this invention The figure which shows the modification at the time of making a core member into a cylindrical member in the ribbon of embodiment The figure which shows the modification of the ribbon for inner cores based on one embodiment of this invention Sectional view of an example of a ribbon constituting a conventional spiral core Partial sectional view of a conventional spiral core Sectional drawing which shows the shrinkage | contraction state after shaping | molding of a thick ribbon

Explanation of symbols

100, 400, 500, 600, 700, 800, 800a, 900 Ribbon 110, 610, 810, 910 Ribbon body 120, 220, 520, 720, 820, 830, 920 Core 200 Spiral core (inner core)
802 Hollow part

Claims (4)

By winding up a flexible ribbon-like or belt-like ribbon having a predetermined diameter with a ribbon body and a fitting part and a fitted part formed on both side surfaces of the ribbon body. For a room temperature shrinkable tube that is formed in a cylindrical body and is provided in a room temperature shrinkable tube made of a rubber elastic body. An inner core,
The fitting part and the fitted part have a saddle shape that can be fitted to each other, and the fitting part is restricted from moving in the adjacent direction of the ribbon with respect to the fitted part and the cylinder Detachably fitted in a direction intersecting the axial direction of the body,
Wherein the central portion in the ribbon body, have a same axis and the axis of the ribbon body and the formed at higher than the ribbon body of the material melting point material, core material is disposed,
Inner core for cold shrink tube. The fitting part and the fitted part are formed with point symmetry about the axis of the ribbon,
The inner core for a cold-shrinkable tube according to claim 1.   The inner core for a cold-shrinkable tube according to claim 1 or 2, further comprising a fitting portion core member extending along a longitudinal direction inside the fitting portion and the fitted portion. The ribbon body is formed in a sectional Men'nori shape, the back surface of the ribbon body is arranged parallel to, and on the front and back surface and both side surfaces of the thick portions, respectively it each equalizing one thickness surrounding the core ,
The inner core for a cold-shrinkable tube according to any one of claims 1 to 3.

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