JP6527759B2 - Cold-shrinkable tube and inner core used therefor - Google Patents

Description

  The present invention relates to a cold-shrinkable tube used to cover and protect a connection portion such as a coated electric wire, and an inner core used for a cold-shrinkable tube.

  2. Description of the Related Art Conventionally, the connection of a coated wire is required to be protected in order to prevent water intrusion and the like. As an example of protection of the connection portion, an elastic tube in a state of being expanded in diameter using the inner core is disposed at the connection portion, and then the inner core is removed to reduce the diameter of the elastic tube and adhere closely at normal temperature. There is.

  As a normal temperature contraction tube which diameter-expanded an elastic tube using an inner core, a temperature contraction tube as shown in FIG. 18 is mentioned, for example. In the cold-shrinkable tube 101 shown in FIG. 18, cylindrical inner cores 111 are disposed on both end sides of the elastic tube 102 so as to expand the diameter of the elastic tube 102. As shown in FIG. 19, the inner core 111 is connected to a pair of inner core halves 111a and 111b having a shape obtained by dividing a cylinder into two along the long axis, and both ends to the inner core halves 111a and 111b. It comprises a handle portion 112. Between the inner core 111 and the elastic tube 102, the folded film 113 is positioned so that the folded portion 113a is on the inner side of the elastic tube 102, and one of the folded portions of the film 113 is fixed to the inner core 111. ing. Further, at least the surface of the film 113 which is folded back and in contact with the films 113 is a surface having a low coefficient of friction. Then, with the connection portion 122 of the covered electric wire 121 positioned substantially at the center of the cold-shrinkable tube 101, the film folded by pulling the handle portion 112 in the longitudinal direction of the covered electric wire 121 for each inner core 111 The contact surfaces of 113 slide to remove the inner core 111 from the elastic tube 102, and the elastic tube 102 contracts and restores its original size to protect the connection portion 122 of the covered wire 121. The mounting of the elastic tube 102 is completed.

JP, 2009-165214, A

  Although protection of the connection part of the covered wire using the above-mentioned cold contraction tube was conventionally performed by the hand of the worker, in the indirect active wire construction method of the overhead wire, the desired work at the tip of the insulating rod Work is being carried out using a hot stick (insulation work bar) having a construction with a tool. However, removal of the inner core 111 requires a space for pulling out the inner core in the length direction of the covered wire 121, and if the covered wire 121 in the vicinity of a portion requiring protection using a cold shrinkable tube is bent, It may be difficult to pull out the inner core. Also, due to the force applied in the length direction of the coated wire 121 for pulling out the inner core, positional displacement of the normal temperature shrinkable tube 101 is likely to occur, the workability deteriorates, and it takes time to remove the inner core 111 There is a possibility that the protection of the connection portion 122 of the electric wire 121 may be incomplete.

Further, in the process of assembling the inner core 111 using the inner core halves 111a and 111b, it is necessary to fix the folded film 113 around the inner core 111, and further, the inner core 111 is attached to the elastic tube 102. In the step of inserting, it is necessary to prevent positional deviation, falling off and damage of the film 113 fixed around the inner core 111, which may make the process and operation complicated.
Furthermore, by pulling out the inner core 111 from the cold-shrink tube 101, in addition to the inner core 111, the film 113 also becomes dust, and the amount of dust after construction becomes large. In order to prevent the problem, there is a problem that it is necessary to lock the inner core 111 with an adhesive tape or the like.
The present invention has been made in view of the above situation, and can securely protect the connection portion of the coated wire in the indirect live wire construction method of the overhead wire, and the waste treatment after the construction is An object of the present invention is to provide an easy-to-use cold-shrink tube and an inner core used for such a cold-shrink tube.

In order to achieve such an object, the cold-shrinkable tube of the present invention comprises a cylindrical elastic body capable of reducing a diameter from an enlarged diameter state and an inner positioned so as to expand the diameter of both end sides of the cylindrical elastic body. and a core, said inner core, I pair of core halves are abutted to be spaced combined cylindrical body der having bisected shape by a plane including the long axis of the cylinder, 1 One of the pair of core halves has a tension member, and one end of the inner core in the long axis direction is located at a desired depth from the end of the cylindrical elastic body, the inner core The other end in the long axis direction of the inner core projects from the end of the cylindrical elastic body, and the pulling member is the end or the end of the inner core projecting from the end of the cylindrical elastic body The other half of the core, which is located in the vicinity of the portion and does not have the pulling member The length of the end portion of the core protruding from the end portion of the cylindrical elastic body is greater than the length of the end of the core half body having the pulling member protruding from the end portion of the cylindrical elastic body The configuration was also large .

As a preferred embodiment of the present invention, when a force is applied to the pulling member so as to be in a direction perpendicular to the long axis direction of the inner core and in a direction away from the inner core, The pair of contacting core halves are configured to be separated with the end of the core half located at a desired depth from the end of the cylindrical elastic body as a fulcrum.
As a preferred embodiment of the present invention, the distance L1 from the end of the cylindrical elastic body to the end in the major axis direction of the inner core projecting from the cylindrical elastic body, and the end of the cylindrical elastic body A ratio (L1 / L2) to a distance L2 from a portion to an end in the major axis direction of the inner core located at a desired depth of the cylindrical elastic body is 2 or more, The distance L1 is configured to be a distance from an end of the cylindrical elastic body to a portion where the pulling member is positioned.

As a preferred embodiment of the present invention, the length of the inner core located at a desired depth of the cylindrical elastic body from the outer diameter D of the inner core which is a cylindrical body and the end of the cylindrical elastic body The ratio (D / L2) to the distance L2 to the end in the axial direction is configured to be 1 or more.
In a preferred embodiment of the present invention, the cylindrical elastic body is a rubber material having a 200% modulus of 5 MPa or less, an elongation at break of 500% or more, and a permanent elongation of 24 mm or less between marking lines.
As a preferred embodiment of the present invention, the thickness on both end sides of the cylindrical elastic body before the diameter expansion by the inner core is in the range of 3 to 10 mm.

The inner core according to the present invention is an inner core for expanding the diameter of the end portion side of the cylindrical elastic body capable of diameter reduction from the diameter expansion state, and the inner core is divided into two by a plane including the long axis of the cylinder. has a pair of core halves having a shape, a pair of said core halves, a configurable cylindrical body by combining separably abuts, a pair of the core halves hand, the major axis have a one end or the end tension in the vicinity member direction, the longitudinal direction of the length of said core halves having no said tension member, the tension member The configuration is such that the length is greater than the length of the core half body in the long axis direction .

As a preferred aspect of the present invention, the pulling member is configured to have an annular shape in which both end portions are joined to one core half.
As a preferred aspect of the present invention, the pulling member is configured to have a shape that protrudes from the core half.
In a preferred embodiment of the present invention, the core half has a tensile strength of 15 MPa or more.

  The cold-shrinkable tube of the present invention can reliably protect the connection portion of the coated wire in the indirect hot wire construction method of the overhead wire, and can reduce the amount of dust after construction. Moreover, the inner core of the present invention can simplify the production of the cold shrinkable tube of the present invention.

FIG. 1 is a cross-sectional view showing an embodiment of a cold shrinkable tube of the present invention. FIG. 2 is a cross-sectional view showing an example of a cylindrical elastic body constituting the cold shrinkable tube of the present invention. FIG. 3 is a perspective view showing an example of an inner core constituting the cold shrinkable tube of the present invention. FIG. 4 is a view for explaining the inner core, and FIG. 4 (A) is a side view of a state where core halves are separated, and FIG. 4 (B) is a portion where core halves are in contact with each other. FIG. FIG. 5: is a figure which shows the state which arrange | positioned the normal temperature contraction tube in the connection part of the coated wire. FIG. 6 is a view for explaining a state where the core half body is separated with the end as a fulcrum when removing the inner core. FIG. 7 is a cross-sectional view showing a cylindrical elastic body disposed so as to protect a connection portion of a covered electric wire by removing two inner cores from a cold shrink tube. FIG. 8 is a perspective view for explaining another embodiment of the inner core of the present invention. FIG. 9 is a perspective view for explaining another embodiment of the inner core of the present invention. FIG. 10 is a perspective view for explaining another embodiment of the inner core of the present invention. FIG. 11 is a perspective view for explaining another embodiment of the inner core of the present invention. FIG. 12 is a perspective view for explaining another embodiment of the inner core of the present invention. FIG. 13 is a perspective view for explaining another embodiment of the inner core of the present invention. FIG. 14 is a cross-sectional view showing another embodiment of the cold shrinkable tube of the present invention. FIG. 15 is a view for explaining a state in which the core half body is separated with the end as a fulcrum when removing the inner core from the cold shrinkable tube shown in FIG. FIG. 16 is a perspective view for explaining another embodiment of the inner core of the present invention. FIG. 17 is a perspective view for explaining another embodiment of the inner core of the present invention. FIG. 18 is a cross-sectional view showing an example of a conventional cold shrinkable tube. FIG. 19 is a perspective view showing an example of an inner core used for a conventional cold shrinkable tube.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The drawings are schematic or conceptual, and the dimensions of the respective members, the ratio of the sizes among the members, and the like are not necessarily the same as the actual ones, and are the same members or the like. Even in some cases, the dimensions and ratios may differ depending on the drawings.

  FIG. 1 is a cross-sectional view showing an embodiment of a cold shrinkable tube of the present invention. In FIG. 1, the cold-shrinkable tube 11 includes a cylindrical elastic body 12 which can be reduced in diameter from an expanded diameter state, and an inner core 21 positioned so as to expand the diameter of both end portions 12 a of the cylindrical elastic body 12. have. One end 21a of the inner core 21 in the major axis direction (the direction indicated by the arrow a in FIG. 1) is positioned at a depth L2 from the end 12a of the cylindrical elastic body 12, The other end 21 b in the long axis direction of 21 protrudes from the end 12 a of the cylindrical elastic body 12 so as to be a distance L 1.

  FIG. 2 is a cross-sectional view showing an example of the cylindrical elastic body 12 constituting the cold shrinkable tube 11, and shows a state in which the diameter is not enlarged. In FIG. 2, in the cylindrical elastic body 12, the small diameter portion 14 having the desired inner diameter d2 is continuous with both ends of the large diameter portion 13 having the desired inner diameter d1, and the relationship is d1> d2. The inner diameter d1 of the large diameter portion 13 of the cylindrical elastic body 12 is substantially the same as the inner diameter d of the inner core 21. The small diameter portion 14 of the cylindrical elastic body 12 can be reduced in diameter from the diameter-expanded state shown in FIG. 1 to an inner diameter of approximately d2 at normal temperature by removing the inner core 21. The length L of the small diameter portion 14 in the major axis direction (the direction indicated by the arrow a in FIG. 2) is the length from the end 12a of the cylindrical elastic body 12 to the end 21a of the inner core 21 in the cold shrinkable tube 11. It is substantially the same as the distance L2. In addition, the length L 'of the large diameter portion 13 of the cylindrical elastic body 12 in the long axis direction (the direction indicated by the arrow a in FIG. 2) is determined in consideration of the dimensions etc. Can be set appropriately.

  Such a cylindrical elastic body 12 may be made of a rubber material. The rubber material has, for example, a 200% modulus of 5 MPa or less, preferably 2 MPa or less, an elongation at break of 500% or more, preferably 700% or more, a permanent elongation of 24 mm or less between marking lines, preferably 22 mm between marking lines The following rubber materials can be used. If the 200% modulus of the rubber material constituting the cylindrical elastic body 12 exceeds 5 MPa, it may be necessary to increase the thickness to increase the strength of the inner core 21. In that case, the desired inner diameter d is secured In order to do so, the outer diameter D of the inner core becomes large, and as a result, insertion of the inner core 21 into the small diameter portion 14 of the cylindrical elastic body 12 becomes difficult, which is not preferable. If the elongation at cutting is less than 500%, breakage of the cylindrical elastic body 12 may occur when inserting the inner core 21 into the small diameter portion 14 of the cylindrical elastic body 12, which is not preferable. In addition, when the permanent elongation exceeds the gauge line distance 24 mm, the contraction of the small diameter portion 14 of the cylindrical elastic body 12 is insufficient, and the cylindrical elastic body 12 disposed so as to protect the connection portion of the covered wire The crimp strength of the coated wire due to the above may be insufficient, and good insulation and waterproof performance may not be obtained, which is not preferable. As such a rubber material, for example, ethylene propylene rubber, silicone rubber, isobutylene isoprene rubber, butadiene rubber, chloroprene rubber and the like, and arbitrary mixtures thereof can be mentioned.

  The above-mentioned 200% modulus is measured in accordance with JIS K 6251. In this case, draw a marked line of 20 mm between the lines on the dumbbell-shaped No. 3 test piece, apply a tensile force to this test piece, and measure the tensile force when the line reaches 60 mm. As a measuring apparatus, a strograph R manufactured by Toyo Seiki Seisaku-sho, Ltd. is used. Moreover, said elongation at the time of a cutting | disconnection is measured based on JISK6251. In this case, draw a marked line of 20 mm between the lines on the dumbbell-shaped No. 3 test piece, apply a tensile force to the test piece, measure the distance between the marked lines at the time of cutting, and calculate the elongation. Moreover, said permanent elongation is measured based on JISK6273. In this case, draw a marked line of 20 mm between the lines on the dumbbell-shaped No. 3 test piece, apply a tensile force to this test piece, maintain the distance between the marked lines at 60 mm, keep at 70 ° C for 24 hours, and cool to room temperature After release, measure the distance between marked lines after 30 minutes.

  Further, the thickness of the small diameter portion 14 of the cylindrical elastic body 12 in the state where the diameter is not expanded can be set in consideration of the above-mentioned physical properties and the like of the rubber material to be used. It can be in the range of 3 to 10 mm. When the thickness of the small diameter portion 14 of the cylindrical elastic body 12 exceeds 15 mm, the strength required for the inner core 21 inserted in the small diameter portion 14 depends on the value of the 200% modulus of the rubber material used. In addition, when removing the inner core 21 described later, the force required to open the core half increases, which may be undesirable. For example, when the 200% modulus of the rubber material to be used is 2 MPa, the thickness of the small diameter portion 14 can be 7 mm.

  FIG. 3 is a perspective view of the inner core 21 constituting the cold-shrink tube 11. FIG. 4 is a view for explaining the inner core 21. FIG. 4 (A) shows that the core halves are separated. FIG. 4B is a partial cross-sectional view of a portion where the core halves are in contact with each other. The inner core 21 is an embodiment of the inner core of the present invention, and has a pair of core halves 23 and 24 having a shape divided into two by a plane including the long axis of the cylinder. The core half body 23 has a semicircular shaft end 23a and a shaft end 23b located at both ends of the cylinder long axis direction (the direction indicated by the arrow a in FIG. 4A) and the cylinder long axis direction And two abutting end portions 23c located in parallel with each other. Further, the core half body 24 is in parallel with the semicircular shaft end 24a located in one of the cylinder long axis directions and the shaft end 24b located in the other of the cylinder long axis direction along the cylinder long axis direction. It has on its periphery two abutment ends 24c located and a beveled end 24d extending from the abutment end 24c to the shaft end 24b. Therefore, the length of the core half 24 constituting the inner core 21 in the longitudinal axis direction of the cylinder is larger than the length of the core half 23 in the longitudinal axis direction of the cylinder. Thus, the core half body 24 has a structure including a cylindrical component 24A that abuts on the core half body 23 to form the cylindrical body 22, and the stress diffusion portion 24B.

The pair of core halves 23 and 24 are combined with the shaft end 23a and the shaft end 24a in such a manner that the shaft end 23a and the shaft end 24a coincide with each other so that the contact end 23c and the contact end 24c can be separated. A cylindrical body 22 is configured. The stress diffusion portion 24B of the core half body 24 extends from the cylindrical body 22 in a bowl shape. The end 21a and the end 21b of the inner core 21 are the ends of the cylindrical body 22 in the direction of the major axis of the cylinder, and not the end of the portion extending from the cylindrical body 22 in a bowl shape.
The inner diameter d of such an inner core 21 can be appropriately set in consideration of the outer diameter of the covered wire to which the cold-shrinking tube is to be attached. For example, a dimension larger by about 5 to 20 mm than the outer diameter of the covered wire It can be done.

  One core half body 23 constituting the inner core 21 has a belt-like tension member 26. Both ends 26 a of the tension member 26 are joined to the outer wall near the axial end 23 b of the core half 23 and project from the core half 23 in an annular shape. The angle θ (see FIG. 4A) formed by the projecting direction of the tension member 26 with respect to the cylindrical major axis direction of the core half body 23 can be appropriately set, for example, in the range of 30 ° to 90 °. In the illustrated example, both ends 26a of the pulling member 26 are joined to the core half 23, or the pulling member 26 is integrally formed with the core half 23, but both ends 26a of the pulling member 26 are shown. By pivotally supporting the core half body 23, the annular tension member 26 may be rotatable around the both end portions 26a.

  Further, as shown in FIG. 4B, an engagement recess 25a is provided at a predetermined position of the contact end 23c of the core half 23, and a predetermined position of the contact end 24c of the core half 24 is provided. An engagement convex portion 25 b is provided. Thereby, when the contact ends 23c and 24c of the core halves 23 and 24 are abutted so as to be separated, the engagement recess 25a and the engagement protrusion 25b are engaged, and the axial end of the cylindrical long axis direction As the positions 23a and 24a coincide with each other, the positional deviation of the core halves 23 and 24 is prevented. The engagement convex portion 25b may be provided at a predetermined position of the abutting end 23c of the core half body 23, and the engagement concave portion 25a may be provided at a predetermined position of the abutting end portion 24c of the core half 24. Also, the engagement concave portion 25a and the engagement convex portion 25b are provided at predetermined positions of the contact end 23c of the core half body 23, and the engagement convex portions are provided at predetermined positions of the contact end 24c of the core half 24. 25b and the convex part 25b for engagement may be provided.

The core half bodies 23 and 24 constituting such an inner core 21 need to have a strength to withstand the contraction force of the cylindrical elastic body 12, and for example, the tensile strength is 15 MPa or more, preferably 20 MPa or more Materials can be used. If the tensile strength is less than 15 MPa, it is necessary to increase the thickness of the core halves 23, 24 and the outer diameter D of the inner core 21 becomes large, and the diameter expansion operation of the cylindrical elastic body 12, the inner core 21 In some cases, the diameter reduction of the cylindrical elastic body 12 after removing the metal is not preferable. Examples of materials used for the core halves 23 and 24 include known materials such as resin materials such as polypropylene, polyethylene, polystyrene, ABS resin, acrylic resin and polyvinyl chloride, and metal materials such as aluminum. The following materials can be appropriately selected and used. The outer wall surfaces of the core halves 23, 24 may be smooth as long as they do not interfere with the removal of the inner core 21 from the normal temperature shrinkable tube 11 described later. It is not necessary to apply a release agent to the surface, to fix the release film, and the like.
In addition, said tensile strength is measured based on JISK7161. In this case, the maximum tensile force and the tensile force at the time of cutting are measured until the test piece having a thickness of 1 mm and a width of 5 mm is cut. As a measuring apparatus, a strograph R manufactured by Toyo Seiki Seisaku-sho, Ltd. is used. Usually, since the tensile force at the time of cutting is equal to or less than the maximum tensile force, it is preferable that the tensile force at the time of cutting be in the range of the above-mentioned tensile strength. When the difference between the maximum tensile force and the tensile force at the time of cutting is large and the tensile strength is sharply reduced after the yield, it is preferable that the maximum tensile force be in the range of the above-mentioned tensile strength.

In addition, the tension member 26 needs to have a strength to endure the force applied at the time of removal of the inner core 21 described later, and can be appropriately selected and used from the materials used for the core halves 23 and 24 described above. it can. In addition, when the pulling member 26 is joined to the outer wall surface of the core half 23, a material that can be joined to the core half 23 can be used.
In the above-described cold shrinkable tube 11, the distance L1 from the end 12a of the cylindrical elastic body 12 to the end 21b of the inner core 21 and the end 12a of the cylindrical elastic body 12 to the end 21a of the inner core 21 As the ratio (L1 / L2) to the distance L2 is larger, removal of the inner core 21 described later is easier. This ratio (L1 / L2) can be, for example, 2 or more, preferably 3 or more. When both ends 26 a of the pulling member 26 are located at a position slightly away from the end 23 b of the core half body 23, the above distance L 1 is from the end 12 a of the cylindrical elastic body 12 to both ends of the pulling member 26. This is the distance to the junction of the portion 26a.

In the cold-shrink tube 11, the ratio (D / L2) of the outer diameter D of the inner core 21 to the distance L2 from the end 12a of the cylindrical elastic body 12 to the end 21a of the inner core 21 increases The removal of the inner core 21 described later is easy. This ratio (D / L2) can be 1 or more, preferably 2 or more.
The cold shrinkable tube 11 of the present invention is obtained by directly inserting the inner core 21 into the small diameter portion 14 of the cylindrical elastic body 12. Therefore, compared to the conventional cold-shrink tube in which the film is interposed to insert the inner core, the process of fixing the film to the inner core is unnecessary, and the complicated process of preventing the film damage when inserting the inner core There is no need for process control, and the cylindrical elastic body 12 can be easily expanded.

  Such a cold-shrinkable tube 11 is disposed on the sheathed wire 1 such that the connection portion 2 of the sheathed wire 1 is positioned substantially at the center of the cylindrical elastic body 12 as shown in FIG. At this time, the stress diffusion portion 24B of the core half body 24 extending in the longitudinal direction of the coated wire 1 passes the coated wire 1 through the cold shrink tube 11 in addition to the diffusion action of the stress acting on the coated wire 1 described later. It also acts as a guide. Then, in one of the two inner cores 21 of the cold shrinkable tube 11, a direction substantially perpendicular to the long axis direction of the inner core 21 and separated from the inner core 21 (the direction indicated by the arrow P in FIG. 5) Force is applied to the pulling member 26 so that The application of the force in the direction of arrow P to the pulling member 26 is carried out, for example, using a hot stick (insulating working rod) having a structure in which a desired working tool is attached to the tip of the insulating rod. It can be performed by holding or hooking. In addition, in FIG. 5, the covered electric wire 1 and its connection part 2 are shown with the dashed-two dotted line.

  As described above, by applying a force in the direction of arrow P to the pulling member 26, as shown in FIG. 6, the pair of abutting core half bodies 23 and 24 are inserted into the cylindrical elastic body 12. Of the boundary 23e between the axial end 23a and the abutting end 23c of the core half 23 and the boundary 24e between the axial end 24a and the abutting end 24c of the core half 24 as a supporting point Separate as. At this time, stress is applied to the coated wire 1 through the core half 24 by the force in the direction of arrow P exerted on the pulling member 26, but the stress diffusion portion 24 B of the core half 24 is in the longitudinal direction of the coated wire 1 Since the stress applied to the coated wire 1 is diffused, bending of the coated wire 1 and damage are prevented. In addition, since the contraction force of the small diameter portion 14 of the cylindrical elastic body 12 is concentrated at the contact point with the boundary portions 23e and 24e by separating the pair of core half bodies 23 and 24 as described above, the boundary portions It is possible that a defect etc. arise in 23e and 24e. For this reason, the boundaries 23e and 24e may be rounded to disperse stress.

  As the separation angle of the pair of core halves 23 and 24 with the contact point with the boundary portions 23e and 24e as a fulcrum by the force in the arrow P direction applied to the pulling member 26, the cylindrical elastic body 12 is The contraction force of the small diameter portion 14 acts to push the inner core 21 to the outside of the cylindrical elastic body 12. As a result, the inner core 21 inserted into the cylindrical elastic body 12 is removed, and the small diameter portion 14 of the cylindrical elastic body 12 is contracted to an inner diameter substantially the same as the original inner diameter d2 and closely attached to the coated wire 1 . Similarly, the remaining inner core 21 of the cold shrinkable tube 11 is removed. FIG. 7 is a cross-sectional view showing the cylindrical elastic body 12 disposed so as to protect the connection portion 2 of the coated electric wire 1 by removing the two inner cores 21 from the cold shrinkable tube 11. The two inner cores 21 may be simultaneously removed from the cold-shrink tube 11. However, it is preferable to remove the inner cores 21 individually in order to reduce the load on the overhead wire.

In the cold shrinkable tube 11 of the present invention, since the force for removing the inner core 21 is applied in the direction of separating from the inner core 21 as described above (the direction indicated by the arrow P in FIG. 5) Positional displacement of the cold shrinkable tube 11 in the direction is less likely to occur. Therefore, the removal operation of inner core 21 from cold-shrink tube 11 can be performed easily and reliably in a short time, and cylindrical elastic body 12 is disposed at the optimum position with respect to connection portion 2 of covered wire 1 It can be set up.
Further, as described above, the normal temperature shrinkable tube 11 of the present invention is the one in which the inner core 21 is directly inserted into the small diameter portion 14 of the cylindrical elastic body 12 and no film or the like is interposed. The amount of dust after disposing the cylindrical elastic body 12 so as to protect the connection portion 2 of the covered electric wire 1 by removing 21 is small, and the sorting process is unnecessary, and a film or the like is blown off by wind. There is no problem as well.

FIG. 8 is a perspective view for explaining another embodiment of the inner core of the present invention. In the inner core 21 'shown in FIG. 8, the positions where the end portions 26a, 26a' of the pulling members 26 included in the core half body 23 constituting the inner core 21 'are joined to the outer wall surface of the core half body 23 are 3 and FIG. 4 (A) are the same as the above-mentioned inner core 21 except for the difference from the pulling member 26 provided in the core half body 23 constituting the inner core 21 shown in FIG.
In the inner core 21 ', one end 26a of the pulling member 26 provided in the core half 23 is joined to the outer wall near the axial end 23b of the core half 23, and the other end 26a' is It is joined to the outer wall surface of the core half body 23 at a position away from the shaft end 23 b in the direction of the cylinder longitudinal axis. The end portions 26a, 26a 'of the pulling member 26 are located on the same line in the longitudinal direction of the cylindrical core 23. The position where the end 26a 'of the pulling member 26 is joined to the outer wall surface of the core half 23 is a portion which protrudes from the normal temperature shrinkable tube when the inner core 21' is inserted into the normal temperature shrinkable tube. In the illustrated example, the same line in the longitudinal direction of the cylinder where the end portions 26a and 26a 'of the pulling member 26 are located is set to be most separated from the two abutting end portions 23c of the core half body 23. The same line may be located in any circumferential direction of the core half 23, for example, may be adjacent in parallel to one of the two abutting ends 23c.

In the inner core 21 ', one end 26a of the pulling member 26 is joined to the outer wall near the axial end 23b of the core half 23, and in the above-mentioned inner core 21, the pulling member 26 has its end Both end portions 26 a are joined to the outer wall surface in the vicinity of the axial end portion 23 b of the core half body 23. In the present invention, at least one end of the pulling member 26 may be joined to the outer wall near the axial end 23b of the core half 23, and the joining position of the other end of the pulling member 26 is the inner core There is no particular limitation as long as it does not inhibit insertion into the cold shrinkable tube to a predetermined depth.
Such an inner core 21 'can be used for the cold-shrink tube of the present invention, as with the above-mentioned inner core 21. Then, when removing the inner core 21 'from the cold-shrink tube, the direction substantially perpendicular to the long axis direction of the inner core 21' and separated from the inner core 21 '(the direction indicated by the arrow P in FIG. Force is applied to the pulling member 26 so that

  FIG. 9 is a perspective view for explaining another embodiment of the inner core of the present invention. The inner core 31 shown in FIG. 9 is a core half body 23 in which the pulling member 36 provided in the core half body 33 constituting the inner core 31 constitutes the inner core 21 shown in FIG. 3 and FIG. Is the same as the above-mentioned inner core 21 except for the difference from the pulling member 26 provided in Therefore, in the inner core 21, the members and portions described with the number of the twentieth set are given the number of the twentieth set in the inner core 31, and the description will be omitted.

  The tension member 36 provided in the core half 33 is in the form of a long plate projecting from the axial end 33 b of the core half 33, and the angle formed by the projecting direction of the tension member 36 with respect to the cylindrical long axis direction of the core half 33. θ can be appropriately set, for example, in the range of 30 ° to 90 °. Further, the pulling member 36 has a wide portion 36a at its tip in order to facilitate and ensure gripping of the pulling member 36 using a hot stick (insulation work bar). The pulling member 36 may be integrally formed with the core half 33. The pulling member 36 may be joined to the axial end 33b of the core half 33. In this case, a material having a desired strength and capable of joining to the core half 33 is appropriately selected. Can be used. The position where the pulling member 36 protrudes from the shaft end 33b of the core half 33 is set to be most separated from both ends of the substantially semicircular shaft end 33b in the illustrated example. The protruding position is not particularly limited as long as it is on the shaft end 33b. The pulling member 36 may project from the outer wall near the axial end 33b of the core half 33. In this case as well, the projecting position is in any circumferential direction of the core half 33. It is also good.

  This inner core 31 can be used for the cold-shrink tube of the present invention, as with the above-mentioned inner core 21. When the inner core 31 is removed from the cold-shrink tube, it is a direction substantially perpendicular to the long axis direction of the inner core 31 and in a direction away from the inner core 31 (the direction indicated by arrow P in FIG. 9). As a result, a force is exerted on the pulling member 36.

FIG. 10 is a perspective view for explaining another embodiment of the inner core of the present invention. The inner core 41 shown in FIG. 10 has a core half body 23 in which the pulling member 46 provided in the core half body 43 constituting the inner core 41 constitutes the inner core 21 shown in FIG. 3 and FIG. Is the same as the above-mentioned inner core 21 except for the difference from the pulling member 26 provided in Therefore, in the inner core 21, the members and parts described in the 20th series are given the 40th series in the inner core 41, and the description is omitted.
The pulling member 46 provided in the core half 43 is provided on the outer wall near the axial end 43 b of the core half 43 and is located at the base 46 a projecting from the core half 43 and the tip of the base 46 a It has the convex part 46b for engagement. The pulling member 46 may be integrally formed with the core half body 43. Alternatively, the pulling member 46 may be joined to the outer wall near the end 43 b of the core half 43, and in this case, a material having a desired strength and capable of being joined to the core half 43 may be used. It can be selected appropriately and used.

This inner core 41 can be used for the cold-shrink tube of the present invention, as with the above-mentioned inner core 21. When the inner core 41 is removed from the cold-shrink tube, it is a direction substantially perpendicular to the long axis direction of the inner core 41 and in a direction away from the inner core 41 (the direction indicated by the arrow P in FIG. 10). As a result, a force is exerted on the pulling member 46.
The shape of the tension member 46 is not limited to the illustrated example, and is not particularly limited as long as the tension member 46 can exert a force so as to be in the direction indicated by the arrow P.

  FIG. 11 is a perspective view for explaining another embodiment of the inner core of the present invention. In the inner core 51 shown in FIG. 11, the contact end 54 c where the core half 54 constituting the inner core 51 abuts on the contact end 53 c of the core half 53 extends as it is and the shaft of the core half 54 It reaches the end 54b. Thus, the core half body 54 has a structure including a cylindrical component 54A that abuts on the core half body 53 to form a cylindrical body, and a stress diffusion portion 54B that extends in a bowl shape from the cylindrical body. . Such an inner core 51 is not provided with the above-described inner core except that the inner core 51 does not have the inclined end portion 24 d provided in the core half 24 constituting the inner core 21 shown in FIGS. 3 and 4A described above. It is similar to 21. Therefore, in the inner core 21, the members and parts described in the 20th series in the inner core 21 are given the 50th series in the inner core 51, and the description will be omitted.

This inner core 51 can be used for the cold-shrink tube of the present invention, as with the above-mentioned inner core 21. When the inner core 51 is removed from the cold-shrink tube, the inner core 51 is in a direction substantially perpendicular to the long axis direction of the inner core 51 and away from the inner core 51 (the direction indicated by the arrow P in FIG. 11). As a result, a force is exerted on the pulling member 56. The pulling member 56 can be made similar to the pulling member 26 constituting the above-mentioned inner core 21.
The pulling member 56 included in the core half 53 of the inner core 51 is the pulling member 26 included in the above-described inner core 21 ′, the pulling member 36 included in the inner core 31, and the pulling member 46 included in the inner core 41. It may be.

  FIG. 12 is a perspective view for explaining another embodiment of the inner core of the present invention. In the inner core 61 shown in FIG. 12, the lengths in the cylindrical axial direction of the pair of core half bodies 63 and 64 constituting the inner core 61 are equal. Such an inner core 61 does not extend in the form of a bowl in the cylindrical body configured by abuttable contact between the contact end portions 63c and 64c of the core halves 63 and 64. Except the point, it is the same as the above-mentioned inner core 21. Therefore, in the inner core 21, the members and portions described with the 20-th order number are given the 60-th order number in the inner core 61, and the description will be omitted.

This inner core 61 can be used for the cold-shrink tube of the present invention, as with the above-mentioned inner core 21. When the inner core 61 is removed from the cold-shrink tube, it is a direction substantially perpendicular to the long axis direction of the inner core 61 and in a direction away from the inner core 61 (the direction indicated by the arrow P in FIG. 12). As a result, a force is exerted on the pulling member 66. The length in the direction of the cylindrical axis of the pair of core halves 63, 64 constituting the inner core 61 is such that when a force in the direction of arrow P is exerted on the pulling member 66 to remove the inner core 61 from the cold shrinkable tube. In order to prevent bending and damage of the coated wire, it can be set appropriately. The pulling member 66 may be similar to the pulling member 26 that constitutes the inner core 21 described above.
The pulling member 66 included in the core half body 63 of the inner core 61 is the pulling member 26 included in the above-described inner core 21 ′, the pulling member 36 included in the inner core 31, and the pulling member 46 included in the inner core 41. It may be.

FIG. 13 is a perspective view for explaining another embodiment of the inner core of the present invention. In the inner core 71 shown in FIG. 13, the lengths of the core half 73 and the core half 74 constituting the inner core 71 in the cylindrical axial direction are equal, and the core half 73 includes the pulling member 76, The core half 74 is similar to the inner core 21 described above, except that it also comprises a tension member 76 '. Therefore, in the inner core 21, the members and portions described with the 20-th order number are given the 70-th order number in the inner core 71, and the description will be omitted.
The pulling member 76 'can be made similar to the pulling member 26 constituting the above-mentioned inner core 21 together with the pulling member 76.

This inner core 71 can be used for the cold-shrink tube of the present invention, as with the above-mentioned inner core 21. When the inner core 71 is removed from the cold-shrink tube, the direction substantially perpendicular to the long axis direction of the inner core 71 and separated from the inner core 71 (shown by arrows P and P 'in FIG. 13) Force is simultaneously applied to the pulling members 76, 76 'so that Therefore, the inner core 71 can be removed while preventing the stress from acting on the coated wire.
The pulling members 76 and 76 'provided in the core half bodies 73 and 74 of the inner core 71 include the pulling member 26 provided in the above inner core 21', the pulling member 36 provided in the inner core 31, and the inner core 41. It may be a pulling member 46 provided.

  In addition, the cold shrinkable tube of the present invention may use an inner core that does not have a pulling member. FIG. 14 is a cross-sectional view showing a cold-shrinkable tube of the present invention in which such an inner core is inserted into a small diameter portion of a cylindrical elastic body and expanded in diameter. In FIG. 14, in the inner core 81 used for the cold shrinkable tube 11, the lengths of the core half 83 and the core half 84 constituting the inner core 81 in the cylindrical axial direction are equal. The inner core 81 has the same length in the cylindrical axial direction of the core half 83 and the core half 84 constituting the inner core 81, and the core half 83 does not have the tension member 76. Except for the above, the same as the inner core 21 described above. Therefore, in the inner core 21, the members and portions described in the 20th series are given the 80th series in the inner core 81, and the description thereof is omitted.

  The inner diameter d of the inner core 81 is set so that the working tool 5 of the hot stick (insulating work rod) can be inserted between the inner core 81 and the coated wire without damaging the coated wire, as illustrated. It is done. When removing the inner core 81 from the cold-shrink tube 11, a direction substantially perpendicular to the long axis direction of the inner core 81 via the working tool 5 of the hot stick inserted between the inner core 81 and the covered electric wire That is, the force is simultaneously applied in the direction of separating from the inner core 81 (the direction indicated by the arrow P and the arrow P ′ in FIG. 14). Thereby, as shown in FIG. 15, the shaft end 83a and the abutting end of the core half 83 in which the pair of abutting core halves 83 and 84 are inserted into the cylindrical elastic body 12 The contact point between the boundary 83e with 83c and the boundary 84e between the axial end 84a of the core half 84 and the abutting end 84c is separated as a fulcrum. Then, the contraction force of the small diameter portion 14 of the cylindrical elastic body 12 acts to push the inner core 81 out of the cylindrical elastic body 12, whereby the inner core 81 inserted in the cylindrical elastic body 12 is The small diameter portion 14 of the cylindrical elastic body 12 is reduced in diameter to substantially the same inner diameter as the original inner diameter d2. The removal of the inner core 81 prevents the stress from acting on the coated wire.

  The embodiments of the above-mentioned cold shrinkable tube and inner core are examples, and the present invention is not limited to these embodiments. For example, the inner core of the present invention is provided with a mark for facilitating making the insertion depth to the small diameter portion of the cylindrical elastic body constant when producing the cold-shrink tube. Good. Taking the inner core 21 of the present invention as an example, for example, as shown in FIG. 16, on the outer wall surface of the core half 23 and the core half 24 constituting the inner core 21, the axial end 21 a of the inner core 21 The protrusions 28a and 28b may be respectively provided as marks 28 so as to be at predetermined positions (distance L2 shown in FIG. 1). Such an inner core 21 is inserted into the small diameter portion of the cylindrical elastic body by inserting the inner core 21 into the small diameter portion of the cylindrical elastic body so that the mark 28 reaches the end of the cylindrical elastic body. The insertion depth can always be constant. In the illustrated example, the projections 28a and 28b are formed in a continuous shape so as to form an annular shape, but the projections 28a and 28b are divided into a plurality of parts in the circumferential direction, or provided at one place on each of the outer wall surfaces It may be Further, if there is no problem in the strength, a groove may be provided on the outer wall surface of the core half body 23, 24 instead of the protrusion to make a mark 28.

  The inner core of the present invention may be one in which two core halves are connected at one place. For example, in the above-mentioned inner core 21 of the present invention, as shown in FIG. 17, the core half body 23 and the core half body 24 constituting the inner core 21 are connected by one hinge 29. Good. In this case, one hinge 29 is provided at a position connecting the shaft end 23 a of the core half 23 and the shaft end 24 a of the core half 24. When removing the two, the pair of core halves 23, 24 are separable as shown in FIG. In FIG. 17, the core half 24 is twisted obliquely upward with respect to the core half 23 in order to show that the core half 23 and the core half 24 are connected by one hinge 29. The relative positions of the core half body 23 and the core half body 24 which are positioned and are in a separated state without constituting the inner core 21 are not limited to the illustrated positions.

Next, the present invention will be described in more detail by showing specific examples.
A cylindrical elastic body made of ethylene propylene rubber was prepared. This cylindrical elastic body has a shape as shown in FIG. 2; the inner diameter d1 of the large diameter portion is 11 mm, the inner diameter d2 of the small diameter portion is 5.3 mm, and the axial length L of the small diameter portion is 6 mm The thickness of the small diameter portion was 7 mm. Further, the 200% modulus of the ethylene-propylene rubber constituting the cylindrical elastic body was 2 MPa, the elongation at cutting was 700%, and the permanent elongation was 22 mm between the marked lines. In addition, 200% modulus is based on JIS K 6251, draw a marked line of 20 mm between the lines on the dumbbell-shaped No. 3 test piece, and reach a tensile strength of 60 mm when it is measured by Toyo Seiki Co., Ltd. It measured using the manufactured strograph R. In addition, elongation at break was calculated in accordance with JIS K 6251 by drawing a marked line of 20 mm between dumbbell-shaped No. 3 test pieces and measuring the distance between the marked lines at the time of cutting to calculate an elongation percentage. In addition, according to JIS K 6273, set the mark line of 20 mm between the lines on the dumbbell-shaped No. 3 test piece, set the distance between the mark lines to 60 mm, hold at 70 ° C for 24 hours, up to room temperature. After cooling, it was released and the distance between marked lines was measured after 30 minutes.

  Moreover, as an inner core of this invention, the inner core as shown by FIG. 3, FIG. 4 was produced using polypropylene. One of the two core halves constituting the inner core has a tension member near the axial end in the longitudinal direction of the cylinder, as shown in FIGS. 3 and 4, and the other core half is: A cylindrical component 24A and a stress diffusion part 24B shown in FIG. 4 are provided. The length of the cylindrical component 24A in the longitudinal direction of the cylinder is 28 mm, and the axial length of the stress diffusion part 24B is 22 mm. The inner diameter d of such an inner core was 15.6 mm, the outer diameter D was 17.6 mm, and the tensile strength of the polypropylene used was 20 MPa. In addition, according to JIS K 7161, the tensile strength is the maximum tensile force and the tensile force at the time of cutting until the test piece of 1 mm in thickness and 5 mm in width is cut. It measured using. In this measurement result, it was the maximum tensile force 引 張 tensile force at the time of cutting.

Next, the above inner core was inserted into the small diameter portions at both ends of the above cylindrical elastic body to produce a cold shrinkable tube as shown in FIG. In this cold-shrink tube, the distance L1 shown in FIG. 1 is 21 mm, the distance L2 is 7 mm, the ratio (L1 / L2) is 3, and the ratio (D / L2) is 2.5.
Next, the cold-shrinkable tube was placed on a covered electric wire having an outer diameter of 8 mm so that the connection portion was positioned approximately at the center of the cylindrical elastic body.

Next, in one of the two inner cores, using a hot stick having a structure in which a desired working tool is attached to the tip of the insulating rod, the ring-shaped pulling member included in the inner core is gripped, The force was applied in a direction substantially perpendicular to the long axis direction of the and the direction away from the inner core (the direction indicated by the arrow P in FIG. 5). As a result, the pair of core halves constituting the inner core are separated as shown in FIG. 6, and by the separation operation of the core halves, the contraction force of the small diameter portion of the cylindrical elastic body is the inner core. The outer core was removed by acting to push the outside of the cylindrical elastic body, and the small diameter portion of the cylindrical elastic body was shrunk to be in close contact with the coated wire. Similarly, the remaining inner core of the cold shrink tube was removed. Thus, the cylindrical elastic body is disposed to protect the connection portion of the coated wire.
The positional deviation of the cold-shrinkable tube with respect to the coated wire in the removal operation of the inner core was not observed, and after the inner core was removed, the connection portion of the coated wire was located approximately at the center of the cylindrical elastic body.

  The present invention is useful in the field requiring an operation of covering and protecting a connection portion such as a covered electric wire.

11: Cold shrinkable tube 12: Cylindrical elastic body 12a: End of cylindrical elastic body 21, 31, 41, 51, 61, 71, 81: Inner core 23, 24, 33, 34, 43, 44, 53, 54, 63, 64, 73, 74, 83, 84 ... core halves 26, 36, 46, 56, 66, 67, 76 ... tension members

Claims (11)

A cylindrical elastic body capable of diameter reduction from an enlarged diameter state, and an inner core positioned to expand the diameter of both end sides of the cylindrical elastic body,
The inner core is I a pair of core halves are abutted to be spaced combined cylindrical body der having bisected shape by a plane including the long axis of the cylinder, a pair of the core halves Have a pulling member on one side of the
One end of the inner core in the long axis direction is located at a desired depth from the end of the cylindrical elastic body, and the other end of the inner core in the long axis direction is the cylindrical Projects from the end of the elastic body ,
The pulling member is located at or near an end of the inner core protruding from an end of the cylindrical elastic body.
The end of the other core half not having the pulling member protrudes from the end of the cylindrical elastic body so that the end of the core half having the pulling member is The cold-shrink tube according to any one of the preceding claims , characterized in that the length is greater than the length of the end of the cylindrical elastic body . When a force is applied to the pulling member so as to be in a direction perpendicular to the long axis direction of the inner core and in a direction away from the inner core, the pair of abutting members The cold-shrink tube as claimed in claim 1 , wherein the core half is separated with the end of the core half located at a desired depth from the end of the cylindrical elastic body as a fulcrum. A distance L1 from an end of the cylindrical elastic body to an end of the inner core protruding from the cylindrical elastic body in the long axis direction, and an end of the cylindrical elastic body from the cylindrical elastic body the ratio of the distance L2 to the long axis direction of the end portion of the inner core is located in the desired depth of the body (L1 / L2) is claim 1, characterized in that at least two or claim 2 Cold shrinkable tube as described in. The cold shrinkable tube according to claim 3 , wherein the distance L1 is a distance from an end of the cylindrical elastic body to a portion where the pulling member is positioned. From the outer diameter D of the inner core which is a cylindrical body and the end of the cylindrical elastic body to the end in the major axis direction of the inner core located at the desired depth of the cylindrical elastic body The cold shrinkable tube according to any one of claims 1 to 4 , wherein a ratio (D / L2) to the distance L2 is 1 or more. The tubular elastic body, 200% modulus 5MPa or less, elongation at break of 500% or more, any of claims 1 to 5 permanent elongation, characterized in that a following rubber materials distance 24mm between marked lines Cold shrinkable tube described in The cold-shrink tube according to any one of claims 1 to 6 , wherein the thickness on both end sides of the cylindrical elastic body before the diameter expansion by the inner core is in a range of 3 to 10 mm. . In the inner core for expanding the diameter of the end portion side of the cylindrical elastic body capable of diameter reduction from the diameter expansion state,
The inner core has a pair of core halves having a shape divided into two by a plane including a long axis of a cylinder,
A pair of the core halves can form a cylindrically shaped body by being separated and brought into abutment and combined,
Hand of the core half of the pair, have a one end or the end tension in the vicinity member of the long axis direction,
The inner diameter of the core half not having the pulling member in the long axis direction is larger than the length of the core half having the pulling member in the long axis direction. core. The inner core according to claim 8 , wherein the pulling member has an annular shape in which both ends are joined to one core half. The inner core according to claim 8 , wherein the pulling member has a shape protruding from the core half. The tensile strength of the said core half body is 15 Mpa or more, The inner core in any one of the Claims 8 thru | or 10 characterized by the above-mentioned.

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