JP2002015647A - Reed conductor for thermal fuse and thermal fuse - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reed conductor for a thermal fuse and a thermal fuse which uses the reed conductor wherein the influence of welding on fusible alloy due to oxidation is reduced. SOLUTION: This is the reed conductor which has a constitution that a metal 2 for the fusible alloy welding which is hard to receive the influence of oxidation by the time lapse is installed on a surface of a tip end part, and is welded to the fusible alloy 10. In addition, this reed conductor 1 is housed in a thin-type insulator case, and the thermal fuse has an improved assembling property at the time of assembling and an improved tensile strength of the reed conductor 1 after assembling.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin-type lead conductor for a thermal fuse and a thermal fuse using the lead conductor.

[0002]

2. Description of the Related Art As a thermal fuse, a cylindrical fuse generally called an axial type is widely used, but recently, as the size and thickness of a machine are reduced, for example, a thin thermal fuse is also actively used. It is used.

A lead conductor used for such a thermal fuse is also formed in a belt shape.

The lead conductor is disclosed in Japanese Patent Application Laid-Open No. 11-40 / 1999.
No. 026 has already been proposed. FIG. 9 shows a perspective view of the lead conductor 1 '.

The lead conductor 1 'is configured such that a copper conductor 2' is provided on the surface of the tip of the lead conductor 1 'made of nickel.

[0006]

However, in the case of using the copper conductor 2 ', its surface is oxidized due to aging,
There is a problem that welding to a fusible alloy becomes difficult.

The present invention has been proposed in view of the above, and it is an object of the present invention to provide a lead conductor for a thermal fuse in which the influence of welding to a fusible alloy by oxidation is reduced.

Another object of the present invention is to provide a thermal fuse in which, when assembling a thermal fuse using the lead conductor, the thermal fuse is improved in assemblability and the tensile strength of the assembled lead conductor is improved.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a thin thermal fuse lead conductor, and the surface of the leading end of the elongated thin plate-shaped lead conductor 1, 100 is hardly affected by welding to a fusible alloy by oxidation. It is characterized in that a metal 2 is provided.

The combination of the lead conductors 1,100 and the metal 2 which is less susceptible to welding to the fusible alloy by oxidation is such that the lead conductors 1,100 are made of copper or a copper alloy and used for welding fusible alloys. The metal 2 is made of tin or silver, or the lead conductor 1, 100 is iron or an iron alloy, and the metal 2 for welding a fusible alloy is made of tin or silver, or the lead conductor 1, 100 is aluminum or an aluminum alloy. Thus, the metal 2 for welding a fusible alloy is made of tin or silver, thereby achieving the above object.

Further, a fusible alloy is welded between a pair of lead conductors 1 provided with a metal 2 for welding a fusible alloy at the tip of an elongated thin plate-like lead conductor 1 made of nickel or a nickel alloy. The molten alloy 10 is provided in a thin insulator comprising the insulating substrate 4 and a lid.

Further, in the thermal fuse of the present invention, a pair of lead conductors 1 having a metal 2 for welding a fusible alloy at a tip end thereof are provided on an upper surface of an insulating substrate 4 constituting a thin insulator with a space therebetween. A thin thermal fuse in which the fusible alloy 10 is provided between the lead conductors and a lid 5 is provided on the fusible alloy 10. From the side end to the other side end, the lead conductor 1,
A strip-shaped recess 6 in which the fusible alloy 10 is provided is formed, and protrusions 7 for positioning and fixing the lead conductor are formed at both ends of the recess 6, and the protrusion 7 is formed on the lead conductor 1. A fitting hole 3 capable of fitting is formed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

[0014]

Embodiment 1 FIGS. 1A, 1B and 2 show an embodiment of the present invention. 1A is a plan view of a lead conductor according to one embodiment of the present invention, FIG. 1B is a side view, FIG.
Shows a perspective view.

In these figures, reference numeral 1 denotes a thin and elongated lead conductor, and the surface of the leading end of the lead conductor 1 is made of a metal or a metal which is hardly affected by oxidation even if it is oxidized during welding of a fusible alloy. A metal 2 for welding a fusible alloy, whose surface is less susceptible to oxidation due to aging than copper, is provided. The thin metal 2 on the surface of the tip becomes a welded portion to the fusible alloy. Reference numeral 3 denotes a mounting hole formed as needed, which is formed slightly outside the tip end where the metal 2 for fusible alloy welding is provided.

The combination of the lead conductor 1 and the metal 2 for welding a fusible alloy provided on the surface of the tip portion thereof is, for example, as follows. Further, the lead conductor 1 may be made of tin (Sn), nickel (N
i), silver (Ag) or the like is appropriately selected and applied as needed. Lead conductor Soluble alloy welding metal Nickel (Ni) or alloy, etc. Tin (Sn) or silver (Ag) nickel alloy Copper (Cu) or copper alloy Tin (Sn) or silver (Ag) Iron (Fe) or iron alloy Tin (Sn) or silver (Ag) Aluminum (Al) or Tin (Sn) or silver (Ag) Aluminum alloy

In the above, when metal 2 is tin,
Since tin is the same element as the fusible alloy, even if it is oxidized, it dissolves together with the oxide at the time of welding, so that it is less susceptible to oxidation and can be welded quickly.

Silver is less susceptible to oxidation than conventional copper.

When the metal 2 is provided on the lead conductor 1, for example, means such as hot-dip plating, electroplating, vacuum deposition, and rolling may be used.

FIGS. 3A to 3D show an insulating substrate 4 for a thermal fuse in which the lead conductor 1 is incorporated.

The insulating substrate 4 is formed of ceramic, an insulating resin molded product or the like, and forms a thin insulator together with a lid 5 described later in FIG. Reference numeral 6 denotes a strip for forming the lead conductor 1 and the fusible alloy, which is formed in a band shape from one side end 6a to the other side end 6b along the length direction of the insulating substrate 4. Protrusions 7 for positioning and fixing the lead conductor, for example, each having a short columnar shape, are formed at both ends of the concave portion 6, respectively. On the upper and lower sides corresponding to both sides of the central portion of the concave portion 6, for example, a rectangular projection 8 is formed. For this reason, the width of the central portion of the concave portion 6 in the vertical direction is reduced by the rectangular horizontally long protrusions 8 formed at the top and bottom, respectively. Reference numeral 9 denotes a lid mounting projection formed along the upper side and the lower side of the concave portion 6, respectively. The protrusion 9 is formed along the length direction of the upper side and the lower side from slightly inside the one end 6a of the insulating substrate 4 to just before the other end 6b.

FIG. 4 shows a pair of lead conductors 1 attached to the concave portion 6 of the insulating substrate 4 with a space therebetween and a low melting point fusible alloy 10 provided in a narrow portion of the concave portion 6 so as to bridge therebetween. Shows the mounted state.

The leading end portion of the strip-shaped lead conductor 1 has substantially the same width as the concave portion 6 so as to be housed in the concave portion 6, and the fitting hole 3 for fitting is fitted in the projecting portion 7. Entered. Therefore, if the hole 3 is aligned with the protrusion 7 of the insulating substrate 4 and the hole 3 is fitted, the lead conductor 1 can be easily positioned and fixed at a predetermined position in the recess 6.
In addition, the tip of the lead conductor 1 is positioned in contact with the end of the protrusion 8. Further, a low-melting-point fusible alloy 10 is provided between a pair of lead conductors 1 provided on the left and right sides of the upper surface of the insulating substrate 4, respectively, and a rosin-based flux is applied.
In this case, the lead conductor 1 and the fusible alloy 1 are soldered.
Although 0 is welded, the metal 2 for welding a fusible alloy made of tin is quickly melted by the solder heat, and the two can be reliably connected.

FIGS. 5A to 5D show a lid 5 which is placed on the upper surface of the insulating substrate 4 on which the lead conductors 1 and the like are provided.

The lid 5 is made of a ceramic, an insulating resin molded product, or the like. The inner surface of the lid 5 is formed in a substantially corresponding uneven shape so as to cover the upper surface of the insulating substrate 4.

That is, the outer peripheral portion of the inner surface of the lid 5 has an edge-like thickness, and a groove 12 for fitting the projection 9 of the build-up of the insulating substrate 4 is formed in the thick portion 11 in a rectangular frame shape. Is formed. Further, a horizontally long rectangular concave portion 13 is formed inside the groove 12, and a concave portion 13 a which can be fitted to the protrusion 7 of the insulating substrate 4 is formed from both sides of the concave portion 13 to the groove 12.

In assembling, as shown in FIG.
The pair of lead conductors 1 and the like are mounted on the upper surface of the insulating substrate 4 as described above, connected to the fusible alloy 10 as shown in FIG. 4, and covered with a lid 5 having the same outer shape as the insulating substrate 4 from above. You can do it. In this case, a sealing agent such as an epoxy resin is injected into the groove 12 of the lid 5. The protrusion 7 of the insulating substrate 4 is provided in the recess 13a.
However, since the groove 12 is formed in a rectangular shape inside the lid 5, it is possible to escape an excess sealant and prevent dripping thereof.

Further, since the concave and convex portions on the upper surface of the insulating substrate 4 and the inner surface of the lid 5 are formed so as to be almost in contact with each other,
The contact area is large, and sufficient strength can be secured.

Further, since the hole 3 of the lead conductor 1 is fitted with the convex portion 7 of the insulating substrate 4, it has a sufficient tensile strength, and does not come out even if it is bent or pulled in use.

FIG. 7 is a plan view of the thermal fuse assembled as described above. In the figure, a part of the lid 5 is cut away to show the internal structure. The fusible alloy 1
A rosin-based flux 14 is applied on top of the surface 0 to prevent oxidation, cleaning, wettability and the like.

In the above embodiment, the insulating substrate 4 may be of a type without the protrusion 7. In this case, it is not necessary to form the mounting hole 3 in the lead conductor 1.

Further, the insulating substrate 4 and the lid 5 are not limited to the illustrated example, but may have other appropriate shapes.

FIG. 8 shows another example of the shape of the lead conductor 100 of the present invention. In this example, a constriction portion 101 for positioning and fixing is formed near the front end portion of the lead conductor 100 when the lead conductor 100 is mounted on an insulating substrate (not shown), and the front surface of the front end portion to be welded to the fusible alloy has A metal 2 for welding is provided. At the opposite end of the lead conductor 100, a mounting portion 102 having an appropriate shape is formed as necessary, and a mounting hole 103 is formed as necessary.

[0034]

As described above, according to the present invention, the lead conductor is provided with a fusible alloy welding metal which is hardly affected by oxidation at the connection with the fusible alloy. Can be.

Also, a mounting hole is formed in the lead conductor,
Forming positioning and fixing projections on the insulating substrate that fits with them allows the lead conductor to be welded to the fusible alloy quickly, as well as assembling the thermal fuse when attaching the lead conductor. Performance is good, and after assembly,
The tensile strength of the lead conductor is also remarkably improved because the mounting hole for the lead conductor is fitted to the projection.

[Brief description of the drawings]

FIG. 1A is a plan view of an embodiment of a lead conductor of the present invention, and FIG. 1B is a side view thereof.

FIG. 2 is a perspective view of the embodiment.

3A and 3B are examples of an insulating substrate on which a lead conductor according to an embodiment of the present invention is incorporated, wherein FIG. 3A is a plan view, FIG. 3B is a longitudinal sectional view taken along line AA in FIG. Right side view, (d)
Shows a front view.

FIG. 4 is a plan view in which a lead conductor is incorporated into an insulating substrate.

FIG. 5A is a plan view of a lid attached to an insulating substrate,
(B) is a sectional view taken along line BB in (a), (c) is a right side view,
(D) shows a front view.

FIG. 6 is an explanatory view for assembling the thermal fuse.

FIG. 7 shows a partially cutaway plan view of a completed thermal fuse.

FIG. 8 shows a plan view of another embodiment of the present invention.

FIG. 9 shows a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 lead conductor 2 fusible alloy welding metal 3 mounting hole 4 insulating substrate 5 lid 6 recess 6 a one side end 6 b other side end 7 lead conductor positioning and fixing projection 8 projection 9 lid mounting projection 10 Fusible alloy 11 Thick part 12 Groove 13 Recess 14 Flux

Claims (4)

[Claims] In a thin thermal fuse lead conductor, a metal (2) which is not easily affected by welding to a fusible alloy due to oxidation is provided on the tip surface of an elongated thin plate-shaped lead conductor (1, 100). A lead conductor for a thermal fuse. 2. A combination of a lead conductor (1,100) and a metal (2) which is less susceptible to welding to a fusible alloy by oxidation, wherein the lead conductor (1,100) is made of copper or a copper alloy. The metal for welding molten alloy (2) is made of tin or silver, or the lead conductor (1,100) is iron or an iron alloy, and the metal for welding fusible alloy (2) is made of tin or silver, or A lead conductor for a thermal fuse, wherein the lead conductor (1,100) is aluminum or an aluminum alloy, and the metal (2) for welding a fusible alloy is made of tin or silver. 3. A pair of lead conductors (1,100), each of which is provided with a metal (2) for welding a fusible alloy at the tip of an elongated thin plate-like lead conductor (1,100) made of nickel or a nickel alloy. A thermal fuse, wherein a fusible alloy (10) is welded, and the fusible alloy (10) is provided in a thin insulator comprising an insulating substrate (4) and a lid (5). 4. A pair of lead conductors (1, 100) having a metal (2) for welding a fusible alloy at a tip end thereof are provided on an upper surface of an insulating substrate (4) constituting a thin insulator with an interval therebetween. And a fusible alloy (10) provided between the lead conductors (1, 100), and a lid (5) provided on the fusible alloy (10). On the upper surface, the lead conductors (1, 10) extend from one end to the other end along the length direction.
0), a strip-shaped recess (6) in which the fusible alloy (10) is disposed
A projection (7) for positioning and fixing the lead conductor is formed at each end of the recess (6), and the projection (7) is fitted to the lead conductor (1,100). A thermal fuse, characterized in that a possible mounting hole (3) is formed.