JP2013206792A - Electric wire fuse and method of manufacturing electric wire fuse - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric wire fuse capable of preventing scattering of a part of a fuse element and drop of the fuse element, and suppressing variation of fusing characteristics, and provide a method of manufacturing the electric wire fuse.SOLUTION: An electric wire fuse 1 includes an electric wire 10 having a conductive core wire 11, and a fuse element 20 containing a metal having a fusion point lower than the core wire 11. The core wire 11 is provided with a holding part 50A which twists the core wire 11 to cover the circumference of the fuse element 20 so as to hold the fuse element 20.

Description

  The present invention relates to a wire fuse and a method for manufacturing a wire fuse, in which when a current exceeding a rating is applied to an electric wire, the electric wire is melted and cut off.

  Conventionally, various proposals have been made for fuses that cut off current when a current exceeding the rating (so-called overcurrent) is supplied to the bus bar.

  This type of fuse is composed of a bus bar having a narrower cross-sectional area than other parts and a low melting point metal (hereinafter, fusible body) made of a metal having a melting point lower than that of the bus bar (for example, tin). It is roughly structured. The bus bar is provided with a caulking portion for caulking the fusible body adjacent to the narrow portion.

  In such a fuse, when an overcurrent is applied to the bus bar, the narrow portion has more Joule heat generation than the other parts, the fusible material melts, and the melted fusible material diffuses into the bus bar and diffuses into the bus bar. Lower the melting point. Thereby, a narrow part melts and can interrupt | block the electricity supply of a bus bar.

JP 2010-92729 A

  By the way, when the configuration of the conventional fuse described above is used for an electric wire made of a core wire and a covering material (in the case of a so-called electric wire fuse), it is difficult to form a caulking portion on the core wire corresponding to the bus bar.

  Even if the caulking portion can be formed on the core wire, when the fusible body reaches the melting point, a part of the fusible body may be scattered or the fusible body itself may fall from the core wire. In this case, the alloy amount of the fusible body is reduced, resulting in variations in the fusing characteristics of the electric wires.

  Accordingly, an object of the present invention is to provide an electric wire fuse and a method for manufacturing the electric wire fuse that can prevent a part of the fusible body from scattering and the fusible body itself from falling and suppress variation in fusing characteristics.

  In order to solve the above-described problems, the present invention has the following features. First, the first feature of the present invention is constituted by an electric wire (electric wire 10) including a conductive core wire (core wire 11) and a soluble body (soluble body 20) made of a metal having a melting point lower than that of the core wire. It is an electric wire fuse (electric wire fuse 1, 2), Comprising: The said core wire has the holding | maintenance part (holding part 50A, 50B) which hold | maintains the said soluble body by twisting the said core wire and covering the circumference | surroundings of the said soluble body. The gist is to be provided.

  According to this feature, the core wire is provided with a holding portion that holds the fusible body by twisting the core wire to cover the periphery of the fusible body. Thereby, when a soluble body reaches melting | fusing point, it can prevent that a part of soluble body scatters and the soluble body itself falls from a core wire. Therefore, even if the fusible body reaches the melting point, variation in fusing characteristics can be suppressed without changing the alloy amount of the fusible body.

  In addition, the holding portion can be easily formed without using a machine tool or the like, and the manufacturing cost of the electric wire fuse can be reduced. In addition, a fusible body can be easily attached to a general-purpose electric wire, and the freedom degree of an electric wire fuse increases.

  A second feature of the present invention is an electric wire fuse according to the first feature of the present invention, wherein a plurality of the core wires are provided, and the holding portion has a plurality of the core wires twisted in a predetermined twist. The gist is to be formed by twisting in a direction (predetermined twisting direction TD).

  According to such a feature, the holding portion is formed by twisting a plurality of core wires in a predetermined twisting direction. That is, the holding portion is formed between the plurality of core wires with the plurality of core wires dispersed. Thereby, the circumference | surroundings of a soluble body can be covered uniformly with a holding | maintenance part, and it can prevent more reliably that a part of soluble body scatters and the soluble body itself falls from a core wire.

  A third feature of the present invention is an electric wire fuse according to the first feature of the present invention, wherein the holding portion is arranged around the fusible body along an extending direction of the electric wire (extending direction SD). The gist is that the core wire is formed by spirally winding the core wire.

  According to this feature, the holding portion is formed by winding the core wire in a spiral shape around the fusible body along the extending direction of the electric wire. This makes it possible to cover the fusible body with the holding portion without separating the plurality of core wires, and more reliably that part of the fusible body is scattered or the fusible body itself falls from the core wire. Can be prevented.

  A fourth feature of the present invention is a method of manufacturing an electric wire fuse including an electric wire including a conductive core wire and a fusible body made of a metal having a melting point lower than that of the core wire, and holds the fusible body. An attaching step of forming a holding portion on the core wire and attaching the soluble body to the holding portion so as to cover the periphery of the soluble body by the holding portion, and melting the molten body by applying heat to the soluble body And a fixing step of fixing the fusible body in the part.

  According to the characteristics of the present invention, it is possible to provide an electric wire fuse and a method for manufacturing an electric wire fuse that can prevent a part of the fusible body from scattering and the fusible body itself from falling and suppress variation in fusing characteristics.

Fig.1 (a) is a perspective view which shows the electric wire fuse which concerns on 1st Embodiment, FIG.1 (b) is sectional drawing which shows the electric wire fuse which concerns on 1st Embodiment. FIG. 2A and FIG. 2B are perspective views showing a manufacturing process of the electric wire fuse according to the first embodiment. Fig.3 (a) is a perspective view which shows the electric wire fuse which concerns on 2nd Embodiment, FIG.3 (b) is sectional drawing which shows the electric wire fuse which concerns on 2nd Embodiment. FIG. 4 is a perspective view showing a manufacturing process of the electric wire fuse according to the second embodiment.

  Next, an embodiment of an electric wire fuse and an electric wire fuse manufacturing method according to the present invention will be described with reference to the drawings. Specifically, the description will be made in the order of (1) the first embodiment, (2) the second embodiment, and (3) other embodiments.

  In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones.

  Accordingly, specific dimensions and the like should be determined in consideration of the following description. Moreover, the part from which the relationship and ratio of a mutual dimension differ also in between drawings may be contained.

(1) First embodiment (Configuration of electric wire fuse)
First, the configuration of the electric wire fuse 1 according to the first embodiment will be described with reference to the drawings. Fig.1 (a) is a perspective view which shows the electric wire fuse 1 which concerns on 1st Embodiment, FIG.1 (b) is sectional drawing which shows the electric wire fuse 1 which concerns on 1st Embodiment.

  As shown in FIG. 1, the electric wire fuse 1 includes an electric wire 10 made of a conductive core wire 11 and an insulating covering material 12, a fusible body 20 as a low melting point metal made of a metal having a melting point lower than that of the core wire 11, A pair of LA terminals 30 fixed to both ends of the core wire 11 are provided.

  The core wire 11 is configured by twisting a plurality of copper wires, and the cross-sectional shape is formed in a substantially circular shape. A heat spot portion 50 is provided at the center portion of the core wire 11 (that is, the center in the extending direction SD of the electric wire 10).

  The heat spot part 50 is comprised by the holding | maintenance part 50A which hold | maintains the soluble body 20 by twisting the core wire 11 and covering the circumference | surroundings (in the embodiment, substantially whole) of the soluble body 20. The holding unit 50A temporarily holds the fusible body 20 before heat-welding the fusible body 20 to the core wire 11. That is, the holding unit 50A covers the soluble body 20 in a state where the soluble body 20 is temporarily held.

  In the first embodiment, the holding portion 50A is configured by a gap 51 formed by twisting a plurality of core wires 11 in a reverse direction RD of a predetermined twisting direction TD (that is, a pre-twisted direction). (See FIG. 2). The holding portion 50 </ b> A is restored by twisting the plurality of core wires 11 in a predetermined twisting direction TD, and covers the fusible body 20 between the plurality of core wires 11.

  The fusible body 20 is held by being covered with the holding portion 50A. The fusible body 20 is made of, for example, a tin alloy. The fusible body 20 is melted by being acted (applied) while being held (temporarily held) by the holding portion 50A, and is welded between the plurality of core wires 11 (see FIG. 1B).

  Each LA terminal 30 is provided with a mounting hole 31. The electric wire fuse 1 is fixed so as to be interposed in the circuit on the power source side and the load side using the mounting hole 31. Each end of each LA terminal 30 and the core wire 11 is fixed by thermal welding and caulking of the caulking portion 32, respectively.

(Wire fuse manufacturing method)
Next, the manufacturing method of the electric wire fuse 1 mentioned above is demonstrated, referring drawings. 2A and 2B are perspective views showing the manufacturing process of the wire fuse 1 according to the first embodiment. In addition, the manufacturing method of the wire fuse 1 which concerns on 1st Embodiment includes the attachment process and the fixing process.

  First, in the attaching step, the holding part 50A for holding the fusible body 20 is formed in the heat spot part 50 of the core wire 11, and the fusible body 20 is attached to the holding part 50A so as to cover the periphery of the fusible body 20 by the holding part 50A. .

  Specifically, as shown in FIG. 2A, a plurality of pre-twisted core wires 11 are twisted in a reverse direction RD of a predetermined twisting direction TD (that is, a pre-twisted direction). As a result, the heat spot portions 50 of the plurality of core wires 11 are separated, and a gap 51 corresponding to the holding portion 50 </ b> A is formed between the plurality of core wires 11.

  And the soluble body 20 is inserted in this holding | maintenance part 50A (gap 51), and as shown in FIG.2 (b), it restore | restores by twisting the several core wire 11 to predetermined | prescribed twist direction TD. The fusible body 20 is covered between the core wires 11. The plurality of core wires 11 do not necessarily have to be twisted in the predetermined twisting direction TD, and the fusible body 20 may be covered by further twisting in the reverse direction RD.

  Next, in the fixing step, the soluble body 20 is melted by applying heat, and the soluble body 20 is welded in the holding portion 50A (between the core wires 11) (see FIG. 1). Then, you may attach an insulating tube, a tape, etc. around the core wire 11 in which the coating | covering material 12 is not provided.

  When a current exceeding the rating (so-called overcurrent) is applied to the electric wire fuse 1 manufactured in this way, the fusible body 20 diffuses into the heat spot portion 50, thereby increasing the resistance value of the heat spot portion 50. , The temperature rises. And since the original resistance value of the heat spot part 50 is larger than other parts, it generates heat more than other parts combined with the increase in resistance due to diffusion of the fusible body 20, and the part of the heat spot part 50 is surely melted. Thus, the energization of the core wire 11 is interrupted.

(Action / Effect)
In the first embodiment described above, the core wire 11 is provided with the holding portion 50 </ b> A that holds the fusible body 20 by twisting the core wire 11 and covering the periphery of the fusible body 20 (almost the whole in the embodiment). . Thereby, when the soluble body 20 reaches melting | fusing point, it can prevent that a part of soluble body 20 scatters and the soluble body 20 itself falls from a core wire. Therefore, even if the fusible body 20 reaches the melting point, variation in fusing characteristics can be suppressed without changing the alloy amount of the fusible body 20.

  In addition, the holding portion 50A can be easily formed without using a machine tool or the like, and the manufacturing cost of the wire fuse 1 can be reduced. In addition, the fusible body 20 can be easily attached to the general-purpose electric wire 10, and the degree of freedom of the electric wire fuse 1 is increased.

  In the first embodiment, the holding portion 50A is formed by twisting a plurality of core wires 11 in a predetermined twisting direction TD. That is, the holding portion 50 </ b> A is formed between the plurality of core wires 11 with the plurality of core wires 11 dispersed. Thereby, the circumference | surroundings of the soluble body 20 can be uniformly covered by the holding | maintenance part 50A, and it can prevent more reliably that a part of the soluble body 20 scatters and the soluble body 20 itself falls from the core wire 11. FIG.

(2) Second embodiment (Configuration of electric wire fuse)
Next, the configuration of the electric wire fuse 2 according to the second embodiment will be described with reference to the drawings. Fig.3 (a) is a perspective view which shows the electric wire fuse 2 which concerns on 2nd Embodiment, FIG.3 (b) is sectional drawing which shows the electric wire fuse 2 which concerns on 2nd Embodiment. In addition, the same code | symbol is attached | subjected to the same part as the wire fuse 1 which concerns on 1st Embodiment mentioned above, and a different part is mainly demonstrated.

  In the first embodiment described above, the holding portion 50A is formed by the gap 51 formed by twisting the plurality of core wires 11 in the reverse direction RD of the predetermined twisting direction TD (that is, the pre-twisted direction). (See FIG. 2A).

  On the other hand, in 2nd Embodiment, as shown in FIG. 3, the holding | maintenance part 50B is formed by winding the core wire 11 spirally along the extension direction SD of the electric wire 10 around the soluble body 20. FIG. Has been. That is, the holding part 50 </ b> B indicates the inside of the core wire 11 (inside the spiral).

  In the second embodiment, the core wire 11 may be configured by twisting a plurality of copper wires, as in the first embodiment, or may be a single wire.

(Wire fuse manufacturing method)
Next, the manufacturing method of the electric wire fuse 2 mentioned above is demonstrated, referring drawings. FIG. 4 is a perspective view showing a manufacturing process of the electric wire fuse 2 according to the second embodiment. In addition, the manufacturing method of the wire fuse 2 which concerns on 2nd Embodiment includes the attachment process and the fixing process similarly to 1st Embodiment.

  First, in the attaching step, the holding part 50B for holding the soluble body 20 is formed in the heat spot part 50 of the core wire 11, and the soluble body 20 is attached to the holding part 50B so as to cover the periphery of the soluble body 20 by the holding part 50B. .

  Specifically, as shown in FIG. 4, the core wire 11 is spirally wound around the fusible body 20 along the extending direction SD of the electric wire 10. Then, as shown in FIG. 3, the fusible body 20 is entirely covered with the core wire 11. Thereby, the soluble body 20 is hold | maintained in the cyclic | annular form of the core wire 11 corresponded to the holding | maintenance part 50B.

  Next, in the fixing step, similarly to the first embodiment, the soluble body 20 is melted by applying heat to the soluble body 20, and the soluble body 20 is fixed to the holding portion 50B (see FIG. 3).

(Action / Effect)
In the second embodiment described above, the manufacturing cost of the electric wire fuse 2 can be reduced and variations in fusing characteristics can be suppressed as in the case of the operation and effect of the first embodiment.

  In 2nd Embodiment, the holding | maintenance part 50B is formed by winding a core wire helically along the extension direction SD of the electric wire 10 around the soluble body 20. FIG. As a result, the soluble body 20 can be covered with the holding portion 50B without separating the plurality of core wires 11, and a part of the soluble body 20 is scattered or the soluble body 20 itself falls from the core wire. It can prevent more reliably.

(3) Other Embodiments As described above, the contents of the present invention have been disclosed through the embodiments of the present invention. However, it is understood that the description and drawings constituting a part of this disclosure limit the present invention. Should not. From this disclosure, various alternative embodiments, examples, and operational techniques will be apparent to those skilled in the art.

  For example, the embodiment of the present invention can be modified as follows. Specifically, the holding portions 50A and 50B have been described as covering the fusible body 20 when the core wire 11 is twisted. However, the present invention is not limited to this. For example, the holding portions 50A and 50B may be formed by bending the core wire 11. The solution 20 may be covered as long as the solution 20 is covered.

  Moreover, although the heat spot part 50 (holding part 50A, 50B) was demonstrated as what is provided in the center location of the core wire 11, it is not limited to this, It is provided near either LA terminal 30. Also good.

  As described above, the present invention naturally includes various embodiments that are not described herein. Therefore, the technical scope of the present invention is determined only by the invention specifying matters according to the scope of claims reasonable from the above description.

DESCRIPTION OF SYMBOLS 1, 2 ... Electric wire fuse 10 ... Electric wire 11 ... Core wire 20 ... Soluble body 30 ... LA terminal 50 ... Heat spot part 50A, 50B ... Holding part 51 ... Air gap

Claims (4)

An electric wire fuse including an electric wire including a conductive core wire and a fusible body made of a metal having a melting point lower than that of the core wire,
The electric wire fuse, wherein the core wire is provided with a holding portion for holding the fusible body by twisting the core wire to cover the periphery of the fusible body. The electric wire fuse according to claim 1,
A plurality of the core wires are provided,
The holding part is formed by twisting a plurality of the core wires in a predetermined twisting direction. The electric wire fuse according to claim 1,
The said holding | maintenance part is formed by winding the said core wire helically along the extension direction of the said electric wire around the said soluble body. A method for producing an electric wire fuse comprising an electric wire including a conductive core wire and a fusible body made of a metal having a melting point lower than that of the core wire,
An attachment step of forming a holding portion for holding the fusible body on the core wire and attaching the fusible body to the holding portion so as to cover the periphery of the fusible body by the holding portion;
And a fixing step of fixing the fusible body in the holding part by applying heat to the fusible body.

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