JP2020057589A - Fireproof wire - Google Patents

Abstract

To provide a fireproof wire preventing the generation of a positional deviation and a gap generated by bending and the like as much as possible to keep stable fire resistance performance.SOLUTION: The fire-proof wire includes: a conductor 3; two fireproof tapes 4, 5 wound around so as to enclose an outer periphery of the conductor 3; and a holding yarn 6 for holding an outer periphery of the fire proof tape 5 of an outer periphery layer, where a center part 5a of the fireproof tape 5 of the outer periphery layer is wound to the fire-roof tape 4 of an inner periphery layer so as to enclose longitudinally, and end parts 5b, 5c are lapped to an outer periphery of the center part 5a by butting each other and folding in an overlap state.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a fire-resistant electric wire that can withstand use for a long time even when exposed to a high temperature or a fire due to a fire or the like.

  Conventionally, various refractory wires have been proposed (for example, see Patent Document 1). FIGS. 10 to 12 show a conventional example of this type of refractory electric wire. As shown in FIG. 10 and FIG. 11, the fire-resistant electric wire 50 includes two twisted insulated cores 51, an intervening body 60 disposed on the outer periphery of the two insulated cores 51, A holding tape 61 wound around the outer circumferences of the two insulated wires 51 and a sheath 62 covering the outer circumference of the holding tape 61 are provided.

  Each insulated wire core 51 has a conductor 52, a fire-resistant tape 53 spirally wound so that an end thereof overlaps the outer periphery of the conductor 52, and an insulator coating 54 that covers the outer periphery of the fire-resistant tape 53. The fire-resistant tape 53 includes a mica layer (not shown) and a film layer (not shown). When the fire-resistant electric wire 50 burns, the mica layer (not shown) of the fire-resistant tape 53 remains and the fire-resistant performance is maintained.

JP-A-7-176220

  By the way, when laying the fire-resistant electric wire 50 or the like, the fire-resistant electric wire 50 may be bent due to external force or the own weight of the fire-resistant electric wire 50 itself. This bending may cause a slip between the fire-resistant tape 53 and the conductor 52, and the fire-resistant tape 53 may be displaced. When the misalignment occurs in the fire-resistant tape 53, it becomes a factor of deteriorating the fire-resistant performance. Also, when the bending force indicated by the arrow in FIG. 12 acts and the refractory wire 50 is bent, a gap is generated at an overlapping portion (overlap) 53a of the end of the fire-resistant tape 53, and the conductive substance 70 is placed in the gap. May invade. Then, heat or a flame outside the fire-resistant wire 50 may be transmitted to the conductor 52 via the conductive material 70.

  In addition, even when the fire-resistant wire 50 is manufactured, if the position of the fire-resistant tape 53 is displaced due to a stress such as a tape tension at the time of winding the fire-resistant tape 53 or a twist of the insulated wire 51 in the twisting process of the insulated wire 51, This is a factor in reducing the fire resistance performance.

  Therefore, the present invention has been made to solve the above-described problems, and it is an object of the present invention to provide a fire-resistant electric wire that minimizes displacement and gap of a fire-resistant tape caused by bending or the like and maintains stable fire-resistant performance. With the goal.

  The present invention includes a conductor, a plurality of refractory tapes wound around the outer periphery of the conductor, and a holding member for pressing the outer periphery of the refractory tape wound around the outermost periphery, wherein the refractory wound around the outermost periphery is provided. The tape is wound so that the center portion is wrapped vertically along the fire-resistant tape wound around the inner periphery than the outermost periphery, and both ends are attached to each other and bent in an overlapped state to form an outer periphery of the central portion. It is a fire-resistant electric wire characterized by being overlapped.

  The present invention further includes a conductor, a plurality of fire-resistant tapes wound around the conductor, and a plurality of pressing members for pressing the outer periphery of each of the plurality of fire-resistant tapes. The fire-resistant tape is wound in the same winding manner, either one of longitudinally-attached or spiral-wound, and the plurality of pressing members are arranged such that the innermost circumference of the fire-resistant tape is longer than the interval between the winding pitches of the outermost circumference of the fire-resistant tape. A fire-resistant electric wire characterized by being wound around a tape by a spiral winding having a narrow pitch pitch.

  According to the present invention, both ends of the fire-resistant tape wound around the outermost circumference are bent in an overlapping state and overlapped on the outer circumference of the central part, and the outer circumference of the fire-resistant tape is pressed by the pressing member. Even if the refractory wire is bent, no displacement occurs at both ends of the refractory tape wound on the outermost periphery, and no gap is generated. Therefore, a situation in which the conductive substance enters through the gap of the fire-resistant tape wound around the outermost periphery does not occur, and the desired fire-resistant performance can be maintained. As described above, stable fire resistance performance can always be maintained.

  According to another aspect of the present invention, since the conductor is covered with a plurality of refractory tapes, and the outer periphery of each refractory tape is pressed by a presser thread, no displacement occurs in the innermost refractory tape. No gap is generated. Accordingly, unlike the conventional example, a situation in which the conductive substance enters the gap formed in the fire-resistant tape does not occur, and the desired fire-resistant performance can be maintained. As described above, stable fire resistance performance can always be maintained.

It is a partially broken perspective view of a fireproof electric wire, showing a first embodiment of the present invention. 1A and 1B show a first embodiment of the present invention, in which FIG. 1A is a cross-sectional view of a fire-resistant electric wire, and FIG. 1A and 1B show a first embodiment of the present invention, in which FIG. 1A is a perspective view of an insulated wire core bent by a bending force acting on a fire-resistant wire, and FIG. 1B is an insulated wire core bent by a bending force acting on a fire-resistant wire. FIG. 1A and 1B show a first embodiment of the present invention, in which FIG. 1A is a cross-sectional view of a single-sided film fire-resistant tape, and FIG. FIG. 4 shows the first embodiment of the present invention, and (a) to (d) are perspective views showing respective manufacturing steps of the insulated wire core. It is a partially broken perspective view of a fireproof electric wire, showing a second embodiment of the present invention. 2A and 2B show a second embodiment of the present invention, in which FIG. 1A is a cross-sectional view of a fire-resistant electric wire, and FIG. 3A and 3B show a second embodiment of the present invention, in which FIG. 3A is a perspective view of an insulated wire core bent by a bending force acting on a fireproof electric wire, and FIG. 2B is an insulated wire core bent by a bending force acting on a fireproof electric wire. FIG. FIG. 7 shows a second embodiment of the present invention, and (a) to (d) are perspective views showing respective manufacturing steps of an insulated wire core. It is a partially broken perspective view of a fireproof electric wire showing a conventional example. It is a sectional view of a fireproof electric wire, showing a conventional example. 1A is a perspective view of an insulated wire core bent by a bending force acting on a fire-resistant electric wire, and FIG. 2B is a cross-sectional view of the insulated wire core bent by a bending force acting on a fire-resistant electric wire. .

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

(1st Embodiment)
1 to 5 show a first embodiment of the present invention. As shown in FIGS. 1 and 2, the fireproof electric wire 1 </ b> A includes two twisted insulated cores 2, an intervening body 10 disposed on the outer periphery of the two insulated cores 2, and intervening bodies 10 and 2. A holding tape 11 wound around the outer periphery of the insulated wire core 2 and a sheath 12 covering the outer circumference of the holding tape 11 are provided. The size of the refractory wire 1A is 14 sq to 400 sq.

  The intervening body 10 fills the gap between the outer circumferences of the two twisted conductors 3, and the outer circumference formed by the two conductors 3 and the intervening body 10 has a substantially circumferential surface. Thereby, the refractory wire 1A as the final product has a circular cross section. The intervening body 10 is formed of, for example, polyethylene (PP) fibrillated yarn.

  The holding tape 11 is formed of a polyester nonwoven fabric, a nylon nonwoven fabric, or the like. The sheath 12 is formed by extruding the outer periphery of the holding tape 11.

  The sheath 12 is formed from a polyolefin resin or a vinyl chloride resin.

  Next, the configuration of each insulated wire core 2 will be described. The insulated core 2 includes a conductor 3, two refractory tapes 4 and 5 forming two refractory layers on the outer periphery of the conductor 3, and an insulator coating 7 covering the outer periphery of the two refractory tapes 5, respectively. Is formed from.

  The conductor 3 is a single-core conductor having a circular cross section. The conductor 3 is formed of a copper material, a copper alloy material, an aluminum material, or the like.

  The two refractory tapes 4 and 5 are formed of a refractory tape 4 forming an inner peripheral layer and a refractory tape 5 wound around the outer periphery of the inner peripheral layer of the refractory tape 4 to form an outer peripheral layer. In the first embodiment, since the number of the fire-resistant tapes 4 and 5 is two (two layers), the fire-resistant tape 5 of the outer peripheral layer is a fire-resistant tape arranged on the outermost periphery, and the fire-resistant tape 4 of the inner peripheral layer is the most. It becomes a fire resistant tape arranged on the inner circumference from the outer circumference.

  The two (two-layer) refractory tapes 4 and 5 are directly overlapped with each other, and are each wound vertically. Specifically, the fire-resistant tape 4 of the inner peripheral layer is wound around the outer periphery of the conductor 3 so that both ends in the width direction overlap with each other. In the drawing, a state where both ends in the width direction overlap is not shown.

  The outer layer fireproof tape 5 is wound around the outer circumference of the inner layer fireproof tape 4 so that the central portion 5a wraps the inner circumferential layer fireproof tape 4 vertically, and both ends 5b and 5c in the width direction. Are bent together in an overlapping state and overlapped on the outer periphery of the central portion 5a (see FIG. 2B). In other words, the outer layer refractory tape 5 is wound around the inner layer refractory tape 4 so as to wrap it in a longitudinally attached manner, and is attached to each other and bent in an overlapped state to form an outer peripheral portion of the outer portion of the center section 5a. And both ends 5b and 5c superimposed on each other.

  As shown in FIG. 4A, the inner peripheral layer fire-resistant tape 4 is a single-sided film fire-resistant tape in which a film b is disposed on one side of a fire-resistant layer a. As shown in FIG. 4B, the fire-resistant tape 5 of the outer layer includes a double-sided film fire-resistant tape in which both surfaces of a fire-resistant layer a are sandwiched between films b.

  The refractory layer a is, for example, a layer in which scales of mica, which is an inorganic substance, are arranged without gaps, and the film b is, for example, a film made of polyethylene. The refractory tape a of the inner peripheral layer is wound around the refractory layer a as the conductor 3 side.

  The presser thread 6 as a presser member is spirally wound around the outer periphery of the refractory tape 5 in the outer peripheral layer. The presser thread 6 is wound at a pitch of 3 mm to 6 mm. The presser thread 6 is a fire-resistant material, for example, a glass yarn. The presser thread 6 holds the outer periphery of the fire-resistant tape 5 so that both ends 5b and 5c of the fire-resistant tape 5 overlap each other, and both ends 5b and 5c of the fire-resistant tape 5 are connected to each other. 5 is kept in close contact with the outer periphery of the central portion 5a.

  Next, a procedure for manufacturing the insulated wire core 2 will be described. As shown in FIG. 5 (a), a fire-resistant tape 4 is wound around the outer periphery of the conductor 3 along the longitudinal direction. Thus, the outer periphery of the conductor 3 is covered with one layer (the inner peripheral layer) of the refractory tape 4.

  Next, a fire-resistant tape 5 is wrapped around the outer periphery of the fire-resistant tape 4 in the inner peripheral layer. Here, as shown in FIG. 5 (b), the central portion 5a of the fire-resistant tape 5 is wound around the fire-resistant tape 4 in the inner peripheral layer so as to be wrapped vertically, and both end portions 5b, 5c in the width direction thereof. Are in a state where they are associated with each other. Then, as shown in FIG. 5 (c), both ends 5b and 5c in an overlapped state are bent in the same direction and overlapped on the outer periphery of the central portion 5a in a close contact state. Thus, the outer periphery of the conductor 3 is covered with the two layers of fireproof tapes 4 and 5.

  Next, as shown in FIG. 5D, the presser thread 6 is spirally wound around the outer periphery of the refractory tape 5 in the outer peripheral layer at a predetermined pitch interval (3 mm to 6 mm). This completes.

  As described above, the insulated wire core 2 of the fireproof electric wire 1A is composed of the conductor 3, the two fireproof tapes 4 and 5 wound so as to wrap the outer periphery of the conductor 3, and the presser thread pressing the outer periphery of the fireproof tape 5 wound around the outermost periphery. The fire-resistant tape 5 wound around the outermost periphery is wound around the fire-resistant tape 4 wound around the inner periphery of the inner periphery of the outer periphery more vertically than the outermost periphery, and both ends 5b, 5c Are attached to each other, bent in an overlapping state, and overlapped on the outer periphery of the central portion 5a.

  Therefore, the bending force shown by the arrows in FIGS. 3A and 3B acts on the insulated core 2 due to the external force acting on the refractory wire 1A and the own weight of the refractory wire 1A itself. Even if it bends, both ends 5b and 5c of the fireproof tape 5 of the outer peripheral layer are bent in an overlapping state and overlapped on the outer circumference of the central portion 5a, and the outer circumference of the fireproof tape 5 is pressed by the presser thread 6. Therefore, no displacement occurs at both ends 5b and 5c of the fire-resistant tape 5, and no gap is generated. Accordingly, unlike the conventional example, a situation in which the conductive substance enters the gap formed in the fire-resistant tape 5 does not occur, and the desired fire-resistant performance can be maintained. As described above, stable fire resistance performance can always be maintained.

  The outer layer fire-resistant tape 5 is a double-sided film fire-resistant tape in which both sides of a fire-resistant layer a are sandwiched between films b. Therefore, when both ends 5b and 5c are bent (see FIG. 5C), there is no possibility that the material (for example, mica) of the refractory layer a is peeled off. Specifically, one end 5b can be bent only loosely in an arc shape, but the other end 5c can be bent at an angle of approximately 360 degrees at the boundary position with the center 5a. (For example, mica) may be damaged so as to peel off from the film b. However, since the material of the refractory layer a (for example, mica) is covered with both films b at the other end 5c, there is no possibility that the material of the refractory layer a (for example, mica) will come off.

  The refractory tape 4 of the inner peripheral layer is wound so as to be wrapped vertically around the outer periphery of the conductor 3. Therefore, even if the bending force as shown by the arrows in FIGS. 3A and 3B acts on the insulating core 2 and the insulating core 2 is bent, the inner peripheral layer of the fire-resistant tape 4 is not spirally wound. No misalignment or gaps occur. As described above, even if the insulated wire core 2 is bent, the fireproof electric wire 1A (the insulated wire core 2) of the first embodiment is displaced not only by the fire-resistant tape 5 of the outer layer but also by the fire-resistant tape 4 of the inner layer. Since no gap is generated, extremely stable fire resistance can be maintained.

  The insulated wire core 2 of the fire-resistant electric wire 1A has a structure in which the strength of the fire-resistant electric wire 1A itself is improved and hardly bends, as compared with the case where the presser thread 6 is not wound, so that the fire resistance performance is improved.

  Two refractory tapes 4 and 5 are wound. Fire resistance performance is improved as compared with the case where one fire resistant tape is wound.

  The two refractory tapes 4 and 5 are both wound vertically. Therefore, the tape winding workability is good.

  The presser thread 6 is spirally wound at a pitch P of 3 mm to 6 mm. Therefore, since the presser thread 6 presses both ends 5b and 5c of the outer layer of the refractory tape 5 in the overlapped state from above at a narrow pitch P, both ends 5b and 5c of the overlapped state are attached. A gap can be reliably prevented. This configuration also improves the fire resistance performance.

  In the first embodiment, the fireproof tape 4 of the inner peripheral layer is wound around the conductor 3 vertically, but may be wound spirally (Z winding, S winding). Although the single-sided film fire-resistant tape shown in FIG. 4A was used as the inner layer fire-resistant tape 4, a double-sided film fire-resistant tape shown in FIG. 4B may be used.

(2nd Embodiment)
6 to 9 show a second embodiment of the present invention. In the fire-resistant electric wire 1B of the second embodiment, similarly to the fire-resistant electric wire 1A of the first embodiment, two pieces of fire-resistant tapes 4 and 5 are wound around the outer periphery of the conductor 3. The outer layer fire-resistant tape 5 becomes the fire-resistant tape arranged at the outermost periphery, and the inner-layer fire-resistant tape 4 becomes the fire-resistant tape arranged at the inner periphery from the outermost periphery.

  The fire-resistant wire 1B of the second embodiment is different from the fire-resistant wire 1A of the first embodiment in that the fire-resistant tape 4 of the inner peripheral layer and the fire-resistant tape 5 of the outer peripheral layer are wound in the same manner of vertical attachment or spiral winding. Each is wound. More specifically, each of the refractory tapes 4 and 5 of the inner peripheral layer and the outer peripheral layer is wound vertically so that both ends in the width direction overlap each other. In the drawing, a state where both ends in the width direction overlap is not shown. However, as in the first embodiment, the fire-resistant tape 5 of the outer peripheral layer is wound in such a manner that ends in both widthwise directions are abutted to each other, folded in an overlapping state, and overlapped on the outer periphery of the central portion. Absent.

  The pressing threads 6A and 6B, which are pressing members, are spirally wound around the outer peripheral layer of the inner layer fireproof tape 4 and the outer circumference of the outer layer fireproof tape 5 respectively. The presser yarns 6A and 6B are wound so that the pitch P2 around the inner layer is smaller than the pitch P1 around the outer layer. Specifically, the presser thread 6B of the outer peripheral layer is wound at a pitch interval of 3 mm to 6 mm, whereas the presser thread 6A of the inner peripheral layer is wound at a pitch interval of 1 mm to less than 3 mm. The presser threads 6A and 6B are made of a fire-resistant material, for example, glass yarn.

  The other configuration is the same as that of the first embodiment, and a duplicate description will be omitted. The same components as those in the first embodiment in the drawings are denoted by the same reference numerals for clarification.

  Next, a procedure for manufacturing the insulated wire core 2 will be described. As shown in FIG. 9A, a fire-resistant tape 4 is wrapped around the outer periphery of the conductor 3 along the longitudinal direction. Thus, the outer periphery of the conductor 3 is covered with one layer (the inner peripheral layer) of the refractory tape 4.

  Next, as shown in FIG. 9B, the presser thread 6A is spirally wound around the outer periphery of the inner layer fireproof tape 4 at a predetermined pitch P1 (1 mm to less than 3 mm).

  Next, as shown in FIG. 9 (c), the refractory tape 5 is wound vertically over the presser thread 6A around the outer periphery of the refractory tape 4 in the inner peripheral layer. Thus, the outer periphery of the conductor 3 is covered with the two layers of fireproof tapes 4 and 5.

  Next, as shown in FIG. 9D, the presser thread 6B is helically wound at a predetermined pitch interval (3 mm to 6 mm) around the outer periphery of the refractory tape 5 in the outer peripheral layer. This completes.

  As described above, the insulated wire core 2 of the fire-resistant electric wire 1B is composed of the conductor 3, the two fire-resistant tapes 4 and 5 wound so as to wrap the outer periphery of the conductor 3, and the plurality of pressing members which press the outer periphery of each of the two fire-resistant tapes 4 and 5. The two refractory tapes 4 and 5 are wound by the same winding method of either the longitudinal attachment or the spiral winding, and the two pressing members 6A and 6B Of the inner peripheral layer of the fire-resistant tape 4 is narrower than the pitch P2 of the inner peripheral layer.

  Therefore, the bending force shown by the arrow in FIGS. 8A and 8B acts on the insulated core 2 due to the external force acting on the refractory electric wire 1B and the own weight of the refractory electric wire 1B itself. Even if the conductor 3 is bent, the conductor 3 is covered with the two layers of the fireproof tapes 4 and 5 of the inner and outer layers, and the outer circumference of each of the fireproof tapes 4 and 5 of the inner and outer layers is a pressing thread 6A. , 6B, no displacement occurs in the refractory tape 4 of the inner peripheral layer, and no gap occurs. Therefore, unlike the conventional example, a situation in which the conductive substance enters the gap formed in the fire-resistant tape 4 does not occur, and the desired fire-resistant performance can be maintained. As described above, stable fire resistance performance can always be maintained.

  The presser thread 6A around which the inner layer fireproof tape 4 is wound has a smaller winding pitch P2 than the presser thread 6B which winds the outer layer fireproof tape 5. Accordingly, it is possible to effectively prevent the displacement of the refractory tape 4 in the inner peripheral layer and the generation of the gap. The presser thread 6B for winding the refractory tape 5 of the outer peripheral layer has a wider winding pitch P1 than the presser thread 6A for winding the refractory tape 4 of the inner peripheral layer. Therefore, the entire length of the presser thread 6B to be used can be short. As described above, the outer circumferences of the inner and outer layers of the fire-resistant tapes 4 and 5 are held by the holding yarns 6A and 6B. Can be prevented.

  The insulated wire core 2 of the refractory wire 1B has a structure in which the strength of the refractory wire 1B itself is improved and hardly bends as compared with a case where the presser threads 6A and 6B are not wound, so that the fire resistance performance is improved.

  Two refractory tapes 4 and 5 are wound. Fire resistance performance is improved as compared with the case where one fire resistant tape is wound.

  The two refractory tapes 4 and 5 are both wound vertically. Therefore, the tape winding workability is good.

  In the second embodiment, both the inner layer fireproof tape 4 and the outer layer fireproof tape 5 are wrapped around the conductor 3 vertically, but the inner layer fireproof tape 4 and the outer layer fireproof tape 5 are wound around the conductor 3. May be wound in a spiral winding (Z winding, S winding).

  In the second embodiment, each of the fireproof tapes 4 and 5 of the inner and outer circumferential layers uses the single-sided film fireproof tape shown in FIG. 4A or the double-sided film fireproof tape shown in FIG. May be used.

(Modification)
In each embodiment, the number of the fire-resistant tapes 4 and 5 wound around the conductor 3 is two (two layers), but may be three or more (three layers).

  In each embodiment, the refractory layer a of the refractory tapes 4 and 5 is formed from mica scales, which are inorganic substances. However, when the refractory wire 1 burns, the refractory layer a finally remains on the outer peripheral side of the conductor 3. Then, it may be formed of a material that retains fire resistance.

  In each embodiment, the fireproof electric wire 1 has two insulated cores 2, but even if it has one insulated core 2, it has three or more insulated cores 2. The present invention can also be applied.

1A, 1B Fireproof wire 3 Conductor 4, 5 Fireproof tape 5a Center 5b, 5c End 6, 6A, 6B Pressing thread (pressing member)
a Refractory layer b Film

Claims (7)

Conductor and
A plurality of fire-resistant tapes wound so as to wrap the outer periphery of the conductor,
A holding member for holding the outer periphery of the fire-resistant tape wound around the outermost periphery,
The fire-resistant tape wound around the outermost circumference is wound so that the center portion is wrapped vertically with the fire-resistant tape wound around the inner circumference than the outermost circumference, and both ends are attached to each other in an overlapping state. A fire-resistant electric wire, wherein the electric wire is bent and overlapped on the outer periphery of the central portion. The fire-resistant wire according to claim 1,
The fire-resistant wire wound on the outermost periphery is a double-sided film fire-resistant tape having both sides of a fire-resistant layer sandwiched between films. The fire-resistant wire according to claim 1 or claim 2,
A fire-resistant electric wire, wherein the fire-resistant tape wound on the inner circumference rather than the outermost circumference is wound so as to be wrapped around vertically. The fire-resistant electric wire according to any one of claims 1 to 3,
A fire-resistant electric wire, wherein the fire-resistant tape wound around the inner periphery than the outermost periphery is a single-sided film fire-resistant tape having a film disposed on one surface of a fire-resistant layer. Conductor and
A plurality of fire-resistant tapes wound so as to wrap the outer periphery of the conductor,
A plurality of pressing members for pressing the outer periphery of each of the plurality of fireproof tapes,
The plurality of fire-resistant tapes are respectively wound by the same winding method of either one of longitudinal attachment or spiral winding,
The plurality of holding members are wound by spiral winding in which the pitch of the inner circumference of the refractory tape is narrower than the pitch of the outer circumference of the refractory tape. . The fire-resistant electric wire according to claim 5,
Each of the holding members is a fire-resistant yarn. It is a fireproof electric wire according to claim 5 or claim 6,
Each of the refractory tapes is a double-sided film refractory tape having both sides of a refractory layer sandwiched between films, or a single-sided film refractory tape having a film disposed on one side of the refractory layer.

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