JPS6147031A - Method of producing temperature fuse - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a method for manufacturing a thermal fuse whose main components are easy-melting 6 alloy and flux, which are widely used to prevent overheating in all kinds of electronic equipment. O Structure of the conventional example and its problems A temperature fuse obtained by the conventional manufacturing method is shown in FIG. 2' and coated with heat-softening resin 3 on the outer periphery of easily fusible metal 1. Next, the openings at both ends of insulating case 4 are coated with insulating paint 6.
, 6' and sealed by casting, etc.

In the temperature fuse constructed in this way, when the openings of the insulating turf 40 are sealed with the insulating paint 6-6' by casting or the like, it is difficult to stably supply the insulating paint 6, 5', and the insulating paint 6, Part of the heat-softening resin 3 adheres to the terminal wire 5', making it difficult to maintain a sealed state.In high temperatures, if the heat-softening resin 3 spouts along the terminal wire 2°2', the easily meltable metal 1 The terminal wires 2 and 2' and the insulating paint 5,
Since a gap is formed between the terminal wires 2 and 6', there is a problem in that the mechanical strength of the terminal wires 2, 2' deteriorates due to bending, tension, twisting, etc. In addition, the insulation case 4 is sealed by sealing one opening with insulation paint 6, curing at a temperature lower than that of the thermoplastic resin 3 and the easily fusible metal 1, and then sealing the other opening with insulation paint 6'. It must be sealed and cured once.
The drawback was that continuous process design was not possible.

OBJECT OF THE INVENTION The present invention has been made to address these conventional problems, and it is an object of the present invention to provide a method for manufacturing a thermal fuse that is excellent in mass production, has strong mechanical strength, and has excellent fusing characteristics. This is the purpose.

Structure of the Invention In order to achieve the above object, the present invention covers the outer periphery of the easily fusible metal with a heat-softening resin, houses the easily fusible metal part in an insulating case having openings at both ends, and then covers the easily fusible metal part with a metal cap. Press fit and fix to the outer periphery of both openings of the above insulation case,
A terminal wire is connected to the metal cap, and then the terminal wire and the metal cap are each chucked with a highly conductive metal chuck, and a current is applied while applying pressure between the terminal wire and the metal cap. It is constructed by welding both ends of the wire and the metal cap, and the metal cap and the above-mentioned easily fusible metal.This makes it possible to manufacture a temperature fuse that is excellent in mass production and has excellent mechanical strength and fusing performance. 0 Description of Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a sectional view of an embodiment of a thermal fuse obtained by the manufacturing method of the present invention. As for its manufacturing method, the terminal wire diameter is 0.
．． 7φ was used. First, the materials are made of soot 1, lead, and bismuth with a melting point of 95. For example, the outer diameter is 2.5jEI, the inner diameter is 1,
2jEII, insert it into one opening of the insulating case 13 made of a ceramic case with a length of 7.0jrjl, heat this insulating case 13 to 70"C, and
and the easily fusible metal 11 are fixed with a thermosoftening resin 12. next,
Metal cap with plated outer periphery 14. ．． 14' (inner diameter 2
．． 4BIIIψ) is press-fitted and fixed to the outer periphery of both openings of the insulating case 130.

If the metal caps 14, 14' are slightly smaller than the insulating case 13, the fixing strength will be stronger when press-fitted. Metal caps 14, 1 press-fitted in this way
Connect terminal wires 15 and 15' to 4'. These terminal wires 15, 15' and metal caps 14°14'
As shown in FIG. 3, the terminal ffM15.15' is connected to the terminal ffM15.
, 14', respectively.

Then, while applying a pressure of approximately skg in the direction of the metal caps 14, 14' to the metal chucks 16, 16' that have chucked the terminal wires 15, 15', between the metal chucks 16, 16' and 17, 17'+7). 50O
A current of A is applied for 17100 seconds. When current is applied in this manner, heat is generated between the terminal wires 15, 15' and the metal caps 14, 14', and the temperature instantly becomes high, causing the terminal wires 15, 15' and the metal caps 114' to become hot.
are fused and connected. Also, due to this heat generation, the inner surfaces of the metal caps 14, 14' and both ends of the easily fusible metal 11 are melted and connected, and finally an insulating paint 18 is applied to maintain stable performance for a long period of time, resulting in a finished product. It is said that When a thermal fuse made using this manufacturing method was heated in silicone oil at a rate of 1°C/min and the fusing temperature was measured, a good result was obtained, fusing between 97.2°C and 98.0°C. .

Effects of the Invention As described above, according to the manufacturing method of the present invention, the easily fusible metal, the metal cap, and the terminal wire can be easily and stably welded, and the terminal wire and the easily fusible metal are not directly connected. In addition, since the metal cap is firmly fixed to the insulating case, there is no deterioration in mechanical strength, which is a drawback of conventional products, and it has stable performance and can be very easily sealed in the opening. It is easy to mass produce, provides a small and inexpensive temperature fuse, and has great practical effects.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional temperature fuse, Fig. 2 is a sectional view of an embodiment of a temperature fuse obtained by the manufacturing method of the present invention, and Fig. 3 is a sectional view showing a terminal wire and a metal cap according to the present invention in a metal chuck. FIG. 3 is a cross-sectional view showing a state when chucking is performed and current is applied. Il...! ...Easily fused metal, 12...Thermosoftening resin, 13...Insulation case, 14, 14'.
...Metal cap, 15, 15'...
Terminal wire, 16, 16', 17, 17'...Good conductive metal chuck. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure s 3 Figure 1'JQ-

Claims (1)

[Claims] The outer periphery of the easily fusible metal is covered with a heat-softening resin that has flux and adhesive properties, and the easily fusible metal part is housed in an insulating case that has openings at both ends, and a metal cap is inserted into both openings of the insulating case. While press-fitting and fixing to the outer periphery, a terminal wire is connected to the metal cap, and then the terminal wire and the metal cap are each chucked with a highly conductive metal chuck, and pressure is applied between the terminal wire and the metal cap. A method for manufacturing a thermal fuse, which comprises applying a current to weld both ends of the terminal wire and the metal cap, and the metal cap and the easily fusible metal.