JPH0794064A - Flat thermal fuse - Google Patents

Abstract

PURPOSE:To provide a flat thermal fuse which is excellent in operating property for the application of a flux to a low melting point fusible metal wire, has a wide thermosensitive area, and can stably hold the low melting point fusible metal wire to the contact with another material and prevent the peeling of an insulating coating. CONSTITUTION:A recessed groove 13 is provided on one surface of a metal plate 1 having a highly heat conductive insulating film 11 at least on one surface. A low melting point fusible metal wire 4 is housed in the recessed groove 13, a flux 5 is adhered thereto, and a resin 6 is molded in the recessed groove 13 to seal the low melting point fusible metal wire 4 and the flux 5 by the resin 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alloy type sheet temperature heater.
It's about

[0002]

2. Description of the Related Art As an alloy type temperature fuse, an insulating film is provided on one side of a metal plate, a low melting point soluble metal wire is disposed on the insulating film, and the low melting point soluble metal wire is insulated and coated. Protect with a body and attach lead wires to both ends of the low melting point fusible metal wire to transfer the heat to the low melting point fusible metal wire no matter where the metal plate is spot heated. 2. Description of the Related Art A planar temperature fuse is known which melts a molten metal wire and stops the operation of a heating source.

For example, in an instantaneous water heater, thermal fatigue of the combustion chamber body plate occurs early due to rapid heating and frequent heating / cooling, and moreover, due to corrosive components in the combustion gas. Corrosion of the body plate also overlapped, holes opened in the body plate,
There is a risk that the combustion gas in the body plate will be ejected to the outside, and in order to eliminate this risk, a heat shield plate is arranged facing the combustion chamber body plate part, and the heat shield plate has a planar shape. A temperature fuse is attached to prevent the jetted combustion gas from contacting the wall surface with a heat shield plate, and the jetted combustion gas comes into contact with the heat shield plate to activate the planar temperature fuse and supply gas by microcomputer control. It is known to close the solenoid valve to stop the combustion of gas.

Conventionally, as such a surface temperature fuse, as shown in (a) of FIG. 4 and (b) of FIG. 4 [a cross-sectional view of FIG. Conductive insulation film 1
A meandering groove 13 'is press-molded on one surface of a metal plate 1'provided with 1', and a low melting point fusible metal wire 5'is housed in this groove 13 ',
It is known that an insulating coating layer 6'is provided on the entire one surface of a metal plate (Japanese Utility Model Laid-Open No. 27558/1993).

Further, as shown in FIG. 5, electrode groups 2 ', ... Are fixed to both ends of one side of a metal plate 1'provided with an insulating film 11' having good thermal conductivity on one side. The low melting point fusible metal wire 5 ′, ... Is bridged, the flux 4 ′ is applied to the low melting point fusible metal wire 5 ′, and the flux coating low melting point fusible metal wire and the electrodes 2 ′ ,. What is covered with a conventional insulating coating layer 6'is known (Japanese Patent Laid-Open No. 5-12972).

[0006]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the sheet temperature fuse shown in FIG. 4, since the low melting point fusible metal wire 5'is housed in the groove 13 ', even if the insulating coating layer 6'is thinned, collision with another object will occur. It is safe because it can prevent the low melting point fusible metal wire 5'from being broken. However, by leaving a gap between the groove 13 ′ and the low melting point fusible metal wire 5 ′, when the low melting point fusible metal wire 5 ′ is melted, the molten metal is flowed through the gap to allow the low melting point to be formed. Since the molten metal wire 5'is fused, the low melting point soluble metal wire 5'cannot be oxidized by the oxygen in the void, and the low melting point soluble metal wire 5'cannot be fused due to the insolubility of the oxide film. It becomes difficult, and deterioration of the fusing action characteristic becomes a problem.

On the other hand, in the sheet temperature fuse shown in FIG. 5, since the flux 4'is applied to the low melting point soluble metal wire 5 ', the above oxidation can be prevented and the low melting point soluble metal can be prevented. When the wire 5'is melted, the interface energy is increased due to contact with the molten flux and spheroidization is promoted, and the molten flux digs into the constricted portion due to the occurrence of the spheroidization to accelerate the division. Good fusing characteristics can be guaranteed. Further, since the insulating coating layer 6'is partially formed on the low melting point soluble metal wire 5'and the electrode 2 ', the insulating coating layer 6 on the other surface (side surface of the insulating coating layer) of the metal plate 1'. It is possible to fully sense heat even in the area where'is not present, and the heat sensitive area is wide. However, when the flux 4 ′ is applied, the flux 4 ′ easily flows and spreads, and the flux layer easily intervenes at the interface between the insulating coating layer 6 ′ and the metal plate 1 ′. 6'is easily peeled off, and there is a big problem especially when the continuous temperature temperature of the flat temperature fuse is higher than the melting point of the flux.

An object of the present invention is to provide a low melting point soluble metal wire with excellent operability for applying a flux to the low melting point soluble metal wire, to have a wide heat sensitive area, and to have a low melting point soluble metal wire against contact with other objects. The present invention is to provide a sheet-like temperature fuse capable of stably holding the temperature and preventing peeling of the insulating coating.

[0009]

DISCLOSURE OF THE INVENTION The planar temperature fuse of the present invention
The groove is provided on one side of a metal plate having an insulating film with good thermal conductivity on at least one side, and the low melting point fusible metal wire is housed in the groove and flux is attached to the groove, and a resin is applied to the groove. Is molded so that the low melting point soluble metal wire and the flux are sealed with resin.

[0010]

[Function] Since the low melting point soluble metal wire is housed in the groove and the flux is applied in the groove, it is possible to prevent the flux from flowing and spreading, and the resin mold body and the metal plate can be prevented. It is possible to avoid the interposition of flux between them and firmly fix the resin mold body. In addition, the low melting point metal wire is sealed with a resin mold, is not oxidized, and has a flux applied, so that it has excellent operability. -The insulating coating by the ridge is limited to only the concave portion, so that even the non-insulating coating portion can be heat-sensitive and has a wide heat-sensitive area.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1A is a plan explanatory view showing an embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line B-B in FIG. In (a) and (b) of FIG. 1, 1 is a metal plate having an insulating thin film 11 having good thermal conductivity on at least one side, for example, an aluminum plate having at least one side anodized, and 2 is on one side of the metal plate 1. It is a press-molded meandering groove. 3 is a flux (lower melting point than the melting point of the low melting point fusible metal wire) applied to the bottom of the recess 2.
Reference numeral 4 denotes a low-melting point fusible metal wire housed in the recessed ridge 2, and lead wires 5 and 5 are connected to both ends thereof.
Are drawn out from each end of the meandering groove 2. Reference numeral 6 denotes a resin molded in the recessed line 2, for example, an epoxy resin adhesive, which is adhered to both side edge portions 20, 20 of the recessed line 2 and the recessed line 2 is sealed by the molded resin 6. Has been done.

Under the normal conditions, the flux 3 does not flow out from the groove 2, and therefore,
Wetting of both side edge portions 20, 20 of the groove 2 by the flux 3 can be well eliminated, and the mold resin 6 and the edge portion 2 of the groove 2 can be eliminated.
0 can be firmly bonded.

In the above-mentioned sheet temperature fuse, when the metal plate 1 is heated and the low melting point metal wire 4 is melted, the interfacial energy of the molten metal at the contact interface with the flux 3 already melted. -Becomes large, spheroidization is promoted,
The molten flux intrudes into the constricted portion generated due to the spheroidization, accelerating the fragmentation of the molten metal and accelerating the operation.

2 (a) to 2 (d) are plan views showing another embodiment of the present invention in the manufacturing process, and FIG. 2 (e) is the ho-ho in FIG. 2 (c). FIG. 2 (f) and FIG. 2 (g) are sectional views of FIG. 2 (d).
2 shows a cross-sectional view and a cross-sectional view along the line. In FIGS. 2A to 2G, 1 is a metal plate, and FIG. 3A is a plan view and FIG. 3B is a plan view.
As shown in [a sectional view taken along line (a) of FIG. 3],
On one surface side of the metal plate 1 having the insulating thin film 11 having good thermal conductivity on at least one surface, a plurality of concave stripes 13 sandwiched between a pair of convex stripes 12 and 12 are press-molded in parallel and adjacent to each other. Between the concave ridges 13, 13 facing each other
130 is press molded. In (a) of FIG. 3, 1
Reference numerals 4, 14 denote flat portions on both sides of one side of the metal plate, and 15, ... Bind holes. As the metal plate 1, a press-formed aluminum plate having an oxide film formed by alumite treatment can be used.

In FIG. 2A, reference numeral 21 (22) is a first insulating plate member, which is a bridge conductor for connecting low melting point fusible metal wires in series on one surface of the insulating plate.
211 (221) is fixed, and the lead conductor 222 is also fixed to the first insulating plate member 22 on one side. 15,
... are binding holes.

2 (b) to 2 (d),
31 (32) is a second insulating plate member, and the cutout 31
The first insulation plate member 21 (22) having 1,321,322
Overlaid on top. 15, ... are binding holes.

At the manufacturing stage shown in FIG.
One side of the metal plate 1 is directed upward, and the first insulating plate member 21 (22) is provided with a conductor (bridge conductor 21
1, 221 and the lead conductor 222) are arranged with the fixed surface facing upward.

At the manufacturing stage shown in FIG. 2B,
Each first insulating plate member 21 (2 in FIG. 2A)
2) Each second insulating plate member 31 (32) is laminated thereon, and the laminated body of the first insulating plate member and the second insulating plate member passes through the binding hole 15 and the plastic rivet ( It is fixed to the metal plate 1 by (not shown). At this stage, the second insulating plate member 31 (3
2) From the notches 311, 321, 322 to the ends 211a, 22 of the bridge conductors 211, 221 of the first insulating plate member 21 (22).
1a or each end 222a of the lead conductor 222 is exposed.

At the manufacturing stage shown in FIG. 2C,
As shown in FIG. 2E, the flux 4 is applied to the bottom of the recess 13 of the metal plate 1, and the low melting point fusible metal wire 5 is housed in the flux applying recess and each low melting point. Both ends of the fusible metal wire 5 are connected to the bridge conductor ends 211a and 221a of the second insulating plate member 21 (22) by soldering or welding, and to the lead conductor ends 222a. -The wires 7, 7 are connected by soldering or welding. The low melting point metal wires 6, ... And the lead wires 7,7 are electrically connected in series by these connections.

At the manufacturing stage shown in FIG.
As shown in FIG. 2F and FIG. 2G, the semi-finished product shown in FIG. 2E is provided with a resin 6, for example, an epoxy resin adhesive, in the groove 13. It is molded so that the low melting point fusible metal wire and the flux are sealed and the bridge conductor ends 211a and 221a and the lead conductor ends 222a and 222a of the first insulating plate member 21 (22). Are insulated by a resin 6 mold.

[0021]

The sheet temperature fuse of the present invention is constructed as described above, and the low melting point soluble metal wire is housed in the recess of the metal plate, and the flux is applied in the recess. Therefore, the flux can be prevented from flowing and spreading, and the resin mold body can be firmly fixed to the portion where the flux is not attached. In addition, since the low melting point metal wire is sealed with a resin mold and does not come into contact with the voids, it is not oxidized and further, since flux is applied,
It exhibits excellent operability, and furthermore, the insulating coating by the resin mold is limited to only the recessed portion, so that the non-insulating coating portion can be made to be heat-sensitive and has a wide heat-sensitive area.

Therefore, according to the present invention, it has excellent operability, has a wide heat-sensitive area, can stably hold the low-melting-point soluble metal wire against contact with another object, and peels the insulating coating. It is possible to provide a planar temperature fuse capable of preventing the above.

[Brief description of drawings]

FIG. 1A is an explanatory view showing an embodiment of the present invention,
1B is a cross-sectional view taken along the line of FIG.

2A to 2D are explanatory views showing an embodiment of the present invention in a manufacturing process, FIG. 2E is a sectional view taken along the line HO in FIG. 2C, and FIG. (F) and (g) of FIG. 2 are a cross-sectional view and a cross-sectional view of (d) of FIG.

3 (a) is a plan view showing the metal plate in FIG. 2, and FIG. 3 (b) is a cross-sectional view taken along line (b) of FIG.

FIG. 4A is an explanatory view showing a conventional example, and FIG. 4B is a cross-sectional view taken along line B-B of FIG.

FIG. 5 is an explanatory diagram showing another conventional example different from the above.

[Explanation of symbols]

 1 Metal Plate 11 Insulating Film 13 Recessed Strip 4 Flax 5 Low Melting Point Metal Wire 6 Resin

Claims (1)

[Claims] 1. A metal sheet having an insulating film on at least one side thereof is provided with a concave line on one side thereof. The low melting point metal wire is housed in the concave line and flux is adhered to the concave line, and a resin is applied to the concave line. A sheet-like temperature fuse characterized in that the low melting point fusible metal wire and the flux are sealed with resin.
Z.