JP2018085192A - Fuse element and method for manufacturing fuse element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuse element capable of reducing manufacturing costs and a method for manufacturing the fuse element.SOLUTION: A fuse element 1 comprises: a fusible part 10 to be fused when currents equal to or more than a rated value flow; and a pair of plate-like connection parts 20 connected to both ends of the fusible part 10 for connecting the fusible part 10 to a circuit in series. The fusible part 10 comprises: a fusible metal part 11 formed integrally with the plate-like connection parts 20 with the same plate-like metal member as the plate-like connection parts 20; and a low melting point plated layer 12 made of materials having a lower melting point than the fusible metal part 11, and formed on both or one surface of the fusible metal part 11 such that an alloy layer 13 of the fusible metal part 11 and itself adjusted in accordance with rating currents is generated between the fusible metal part 11 and itself by adjusting temperature and time of heat treatment applied to the fuse element 1.SELECTED DRAWING: Figure 3

Description

  The present invention has a fusible part that is fused when a current exceeding the rating flows, and a pair of plate-like connecting parts that are connected to both ends of the fusible part in order to connect the fusible part in series with the circuit. The present invention relates to a fuse element and a method for manufacturing the fuse element.

  Conventionally, it has a fusible part that is fused when a current exceeding the rating flows, and a pair of plate-like connecting parts connected to both ends of the fusible part in order to connect the fusible part in series with the circuit. In the fuse element, the low melting point metal is fixed to the fusible portion, and when a current exceeding the rated value flows, the fusible portion is melted and cut by melting the low melting point metal.

  For example, in Patent Document 1, in order to prevent oxidation of a caulking portion for fixing a low melting point metal to a fusible metal conductor, the fusible metal conductor and the low melting point metal are melt-connected with another low melting point metal. A fuse and a method of manufacturing the same have been proposed.

JP-A-1-241728

  However, in the technique described in Patent Document 1, the thickness, width, material conductivity, etc. of the fusible metal conductor must be changed according to various rated currents. There is a problem that the manufacturing cost increases because it is necessary to prepare a mold for each type of fuse element.

  This invention is made | formed in view of the above, Comprising: It aims at providing the manufacturing method of the fuse element which can reduce manufacturing cost, and a fuse element.

  In order to solve the above-described problems and achieve the object, a fuse element according to claim 1 of the present invention includes a fusible part that is blown when a current exceeding a rating flows, and the fusible part in series with the circuit. A fuse element having a pair of plate-like connecting portions connected to both ends of the fusible portion for connection, wherein the fusible portion is the same plate-like metal member as the plate-like connecting portion And a meltable metal portion formed integrally with the plate-like connecting portion, and a material having a lower melting point than the fusible metal portion, and the temperature and heat treatment time of the heat treatment applied to the fuse element are adjusted. As a result, an alloy layer with the fusible metal part adjusted according to the rated current is formed on both sides or one side of the fusible metal part so as to be generated between the fusible metal part. A low melting point plating layer, That.

  The fuse element according to claim 2 of the present invention is characterized in that, in the above invention, the soluble metal portion is made of copper or a copper alloy, and the low melting point plating layer is made of tin.

  In order to solve the above-described problems and achieve the object, a method for manufacturing a fuse element according to claim 3 of the present invention includes: a fusible portion that is blown when a current exceeding a rating flows; And a pair of plate-like connecting portions connected to both ends of the fusible portion, so that the fusible portion is the same as the plate-like connecting portion of the fusible portion. A low melting point plating layer made of a material having a lower melting point than that of the fusible metal part is formed on both sides or one side of the fusible metal part integrally formed with the plate-like connecting part. Adjusting the melting point plating layer forming step, the temperature and heat treatment time of the heat treatment applied to the fuse element, the soluble metal part generated between the soluble metal part and the low melting point plating layer, and the The formation state of the alloy layer with the low melting point plating layer Characterized in that it comprises a, an alloy layer produced conditioning step of adjusting in accordance with the rated current.

  According to a first aspect of the present invention, there is provided a fuse element comprising: the fusible metal portion adjusted according to a rated current and the low melting point plating by adjusting a temperature and a heat treatment time of heat treatment applied to the fuse element. Since an alloy layer with the layer is generated between the soluble metal portion and the low melting point plating layer, the thickness, width, material conductivity, etc. of the soluble metal portion can be set according to various rated currents. There is no need to change, and the mold for forming the fuse element can be shared without changing, and as a result, the manufacturing cost can be reduced.

  In the fuse element according to claim 2 of the present invention, since the fusible metal portion is made of copper or a copper alloy and the low melting point plating layer is made of tin, it is easy to use a material generally used for a fuse element. Can be manufactured.

  According to a third aspect of the present invention, there is provided a method for manufacturing a fuse element, wherein the low melting point plating layer forming step has a low melting point on both sides or one side of the fusible metal portion of the fusible portion as compared with the fusible metal portion. A low melting point plating layer made of a material is formed, and the temperature and time of heat treatment applied to the fuse element are adjusted by the alloy layer generation state adjusting step, thereby adjusting the allowable current adjusted according to the rated current. Since an alloy layer of the molten metal part and the low melting point plating layer is generated between the soluble metal part and the low melting point plating layer, the thickness and width of the soluble metal part according to various rated currents Alternatively, it is not necessary to change the material conductivity and the like, and the mold for forming the fuse element can be shared without changing, and as a result, the manufacturing cost can be reduced.

FIG. 1 is a perspective view of a fuse element according to an embodiment of the present invention. FIG. 2 is a view showing a state in which the fuse element is attached to the housing. 3A is a side view of the fuse element, and FIG. 3B is a cross-sectional configuration diagram of the fusible portion of the fuse element that has been heat-treated so that an alloy layer is formed on the fuse element. 4A is a cross-sectional configuration diagram of a fusible portion of a fuse element that is not subjected to heat treatment, and FIG. 4B is a cross-sectional configuration diagram of a fusible portion of the fuse element that has been subjected to heat treatment. FIG. 5 is a diagram for explaining a method of manufacturing a fuse element. FIG. 6A is a side view of the fuse element of the modified example, and FIG. 6B is a fusible state of the fuse element of the modified example in which heat treatment is performed so that an alloy layer is formed on the fuse element of the modified example. It is a section lineblock diagram of a portion.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a fuse element and a method for manufacturing a fuse element according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view of a fuse element 1 according to an embodiment of the present invention. FIG. 2 is a view showing a state where the fuse element 1 is attached to the housing H. FIG. 3A is a side view of the fuse element 1, and FIG. 3B is a cross-sectional configuration of the fusible portion 10 of the fuse element 1 that has been heat-treated so that the alloy layer 13 is formed on the fuse element 1. FIG. FIG. 4A is a cross-sectional configuration diagram of the fusible portion 10 of the fuse element 1 that is not heat-treated, and FIG. 4B is a cross-sectional configuration diagram of the fusible portion 10 of the fuse element 1 that has been heat-treated. .
The fuse element 1 according to the embodiment of the present invention is connected to both ends of the fusible part 10 in order to connect the fusible part 10 in series with the fusible part 10 and the fusible part 10 which are blown when a current exceeding the rating flows. And a pair of plate-like connecting portions 20.

First, the soluble part 10 will be described.
As shown in FIG. 4, the fusible part 10 has a fusible metal part 11 and a low melting point plating layer 12 in a cross-sectional configuration. Between the melting point plating layer 12, an alloy layer 13 of the soluble metal part 11 and the low melting point plating layer 12 is generated.

  As shown in FIG. 1, the fusible portion 10 is a portion that connects a pair of plate-like connecting portions 20 in a narrow band shape so as to be easily melted, and has a width from both sides at a substantially central position. The resistance value is increased by forming the notch 10a so as to further narrow the width toward the inner side in the direction.

The fusible metal portion 11 is the same plate-like metal member as the plate-like connection portion 20, and is a portion formed integrally with the plate-like connection portion 20.
In this embodiment, the soluble metal part 11 is made of copper or a copper alloy.

The low melting point plating layer 12 is made of a material having a melting point lower than that of the fusible metal portion 11, and is adjusted according to the rated current by adjusting the temperature and time of the heat treatment applied to the fuse element 1. It is a tin plating layer formed on one surface of the soluble metal part 11 so that the alloy layer 13 with the soluble metal part 11 is generated between the soluble metal part 11.
Note that the low melting point plating layer 12 may have a thickness of 50 μm or more.

  Since the alloy layer 13 is a layer made of an alloy of the fusible metal portion 11 and the low melting point plating layer 12, it is made of an alloy of copper and tin in this embodiment.

As shown in FIG. 3B and FIG. 4B, the alloy layer 13 is generated between the soluble metal portion 11 and the low melting point plating layer 12, thereby forming the soluble metal portion 11. The thickness becomes thinner.
Thus, the alloy layer 13 having a lower conductivity than the fusible metal part 11 is generated so that the thickness of the fusible metal part 11 is reduced, and the resistance value of the fusible part 10 is increased. The value of the rated current of the fuse element 1 becomes low.

  The applicant of the present invention adjusts the temperature and time of the heat treatment applied to the fuse element 1 to adjust the fusible metal portion 11 generated between the fusible metal portion 11 and the low melting point plating layer 12. It has been confirmed by experiments that the state of formation of the alloy layer 13 between the low melting point plating layer 12 and the low melting point plating layer 12 is adjusted, so that the rated current of the fuse element 1 can be adjusted.

More specifically, a soluble portion in which a low melting point plating layer 12 made of tin is formed to a thickness of 0.1 mm on one surface of a soluble metal portion 11 made of a copper alloy having an electrical conductivity of 39% and a plate thickness of 0.25 mm. When the fuse element 1 having 10 is not subjected to heat treatment, the alloy layer 13 is not generated and the rated current is 40 A as shown in FIG.
On the other hand, when the same fuse element 1 is subjected to a heat treatment at a temperature of 190 ° C. for 250 hours, as shown in FIG. The alloy layer 13 is generated between the portion 11 and the low melting point plating layer 12, and the rated current is 30A, which is lower than that when the heat treatment is not performed.

Next, the pair of plate-like connecting portions 20 will be described.
Each plate-like connecting portion 20 of the pair of plate-like connecting portions 20 is fixed to each end of the soluble portion 10 with respect to the soluble portion 10 by a plate-like metal member integrated with the soluble metal portion 11 of the soluble portion 10. It is connected linearly.
Each plate-like connecting portion 20 has a simple flat plate shape so as to be in surface contact with a terminal (not shown) on the circuit side.
Each plate-like connecting portion 20 has a connection fixing hole 20a through which a fixing member such as a screw for connecting and fixing the terminal on the circuit side is inserted.

  As shown in FIG. 2, such a fuse element 1 is held and accommodated in an insulating housing H such that the periphery of each connection fixing hole 20a of the pair of plate-like connection portions 20 is exposed to the outside.

Next, the manufacturing method of the fuse element 1 is demonstrated using FIG.
FIG. 5 is a diagram for explaining a method of manufacturing the fuse element 1.
First, a plate-like metal member made of copper or a copper alloy constituting the fusible metal portion 11 and the pair of plate-like connecting portions 20 integral with the fusible metal portion 11 by a die pressing step (see FIG. 5A). Is pressed into a predetermined shape by a die press.
Thereby, the external shape of the fuse element 1 is processed into a predetermined shape.

Thereafter, a low melting point plating layer made of a material having a lower melting point than the soluble metal part 11 on one surface of the soluble metal part 11 of the soluble part 10 by a low melting point plating layer forming step (see FIG. 5B). 12 is formed.
Here, the low melting point plating layer 12 is formed in a region corresponding to the fusible portion 10 of the fuse element 1 using a technique such as partial plating.

Thereafter, the temperature and heat treatment time of the fuse element 1 are adjusted by using an apparatus such as an oven by an alloy layer generation state adjusting step (see FIG. 5C), so that the fusible metal portion 11 and the low melting point plating are formed. The production | generation state of the alloy layer 13 of the soluble metal part 11 produced | generated between the layers 12 and the low melting-point plating layer 12 is adjusted according to a rated current.
Here, for example, when no heat treatment is performed on the same fuse element 1 as in the above-described experiment, a fuse element 1 with a rated current of 40 A is manufactured, and when a heat treatment is performed at 190 degrees for 250 hours, The fuse element 1 of 30A is manufactured.

  The fuse element 1 according to the embodiment of the present invention includes a fusible metal portion 11 and a low melting point plating adjusted according to a rated current by adjusting a temperature and a heat treatment time of the heat treatment applied to the fuse element 1. Since the alloy layer 13 with the layer 12 is generated between the soluble metal part 11 and the low melting point plating layer 12, the thickness, width, or material conductivity of the soluble metal part 11 according to various rated currents. Therefore, the mold for forming the fuse element 1 can be shared without changing, and as a result, the manufacturing cost can be reduced.

  In the fuse element 1 according to the embodiment of the present invention, the fusible metal portion 11 is made of copper or a copper alloy, and the low melting point plating layer 12 is made of tin. Therefore, a material generally used for a fuse element is used. It can be manufactured easily.

In addition, the method of manufacturing a fuse element according to the embodiment of the present invention includes a low melting point plating layer forming step in which a material having a low melting point is formed on both sides or one side of the soluble metal portion of the soluble portion as compared with the soluble metal portion. The low melting point plating layer 12 is formed, and the temperature and time of the heat treatment applied to the fuse element 1 are adjusted by the alloy layer generation state adjusting step, so that the solubility is adjusted according to the rated current. Since the alloy layer 13 of the metal part 11 and the low melting point plating layer 12 is generated between the soluble metal part 11 and the low melting point plating layer 12, the thickness of the soluble metal part 11 according to various rated currents, It is not necessary to change the width or the material conductivity, and the mold for forming the fuse element can be shared without changing, and as a result, the manufacturing cost can be reduced.
(Modification)

Next, a modification of the fuse element 1 according to the embodiment of the present invention will be described with reference to FIG.
6A is a side view of the fuse element 2 of the modified example, and FIG. 6B is a fuse element of the modified example in which heat treatment is performed so that the alloy layer 13 is generated on the fuse element 2 of the modified example. FIG. 3 is a cross-sectional configuration diagram of two soluble portions 30.
The fuse element 2 of the modification is different from the fuse element 1 of the embodiment in that the low melting point plating layer 12 is formed on both surfaces of the fusible metal part 11 of the fusible part 30.
Other configurations are the same as those of the embodiment, and the same components as those of the embodiment are denoted by the same reference numerals and the description thereof is omitted.

  When heat treatment is performed on the fuse element 2 so that the alloy layer 13 is generated, the alloy layer 13 is generated on both sides of the fusible metal portion 11 as shown in FIG.

  The fuse element 2 of this modified example has the same effect as the fuse element 1 of the embodiment, and the alloy layers 13 are formed on both sides of the fusible metal part 11, so that the alloy is more alloyed to the same heat treatment condition. Since the layer 13 is easily generated, the heat treatment time for reducing the rated current value is reduced as compared with the fuse element 1 of the embodiment in which the alloy layer 13 is generated on one surface of the fusible metal portion 11. It can be shortened.

  In addition, although fuse element 1, 2 which concerns on the Example and modification of this invention illustrated that the meltable metal part 11 consists of copper or a copper alloy, and the low melting-point plating layer 12 consists of tin, it is not restricted to this. First, the fusible metal portion 11 and the low melting point plating layer 12 are combinations of other types of metals as long as they are a combination of metals that can generate an alloy layer 13 according to the rated current by heat treatment. It doesn't matter.

  Further, in the fuse elements 1 and 2 according to the embodiment and the modified example of the present invention, the plate-like connection portions 20 of the pair of plate-like connection portions 20 are connected to the soluble portion 10 at the respective end portions of the soluble portion 10. However, the present invention is not limited to this, and each plate-like connection portion 20 of the pair of plate-like connection portions 20 is connected to each end portion of the soluble portion 10 with respect to the soluble portion 10. May be bent and connected.

  The invention made by the present inventor has been specifically described based on the above-described embodiments of the invention. However, the present invention is not limited to the above-described embodiments of the invention and does not depart from the gist thereof. Various changes can be made.

DESCRIPTION OF SYMBOLS 1, 2 Fuse element 10, 30 Soluble part 10a Notch part 11 Soluble metal part 12 Low melting point plating layer 13 Alloy layer 20 Plate-shaped connection part 20a Connection fixing hole H Housing

Claims (3)

A fusible part that is blown when a current exceeding the rating flows, and a pair of plate-like connecting parts connected to both ends of the fusible part in order to connect the fusible part in series with the circuit; In the fuse element
The soluble part is
A fusible metal part integrally formed with the plate-like connection part using the same plate-like metal member as the plate-like connection part;
The fusible metal part, which is made of a material having a lower melting point than the fusible metal part, is adjusted according to the rated current by adjusting the temperature and heat treatment time of the heat treatment applied to the fuse element. A low melting point plating layer formed on both sides or one side of the fusible metal part so that an alloy layer of
Fuse element characterized by having. The soluble metal part is
Made of copper or copper alloy,
The low melting point plating layer is
It consists of tin. The fuse element of Claim 1 characterized by the above-mentioned. A fusible part that is blown when a current exceeding the rating flows, and a pair of plate-like connecting parts connected to both ends of the fusible part in order to connect the fusible part in series with the circuit; In the manufacturing method of the fuse element
Lower melting point compared to the fusible metal part on one or both sides of the fusible metal part formed integrally with the platy connecting part with the same platy metal member as the plate-like connecting part of the fusible part A low melting point plating layer forming step of forming a low melting point plating layer made of the material,
An alloy of the fusible metal part and the low melting point plating layer produced between the fusible metal part and the low melting point plating layer by adjusting the temperature and heat treatment time of the heat treatment applied to the fuse element An alloy layer generation state adjustment step of adjusting the generation state of the layer according to the rated current;
A method for manufacturing a fuse element, comprising:

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