JPS603473Y2 - temperature fuse - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a temperature fuse that opens a conductive path above a certain temperature.

Conventionally, there are two types of temperature fuses known: those whose fusible material is an easily fusible metal and those made of an insulating organic material, but those whose fusible material is an easily fusible material are simple in structure, easy to manufacture, inexpensive, and easy to use. On the other hand, since electricity is applied to the easily fusible metal that makes up the fusible body, the internal resistance of the temperature fuse is determined by the specific resistance of the easily fusible metal, and the disadvantage is that the shape has to be large in order to reduce the internal resistance required for the temperature fuse. have.

On the other hand, when the fusible material is an insulating organic material, the internal resistance is determined by the contact resistance of the contacts, so the current capacity increases by reducing the contact resistance of the contacts, and the fusing temperature also increases due to the melting of the insulating organic material. Although this determination results in high accuracy, it has the drawback of requiring a complicated structure in order to reduce the contact resistance of the contacts, resulting in high costs.

This invention relates to an improvement of a temperature fuse using an insulating organic material.While taking advantage of the conventional features of large current capacity and high fusing temperature accuracy, the present invention is a temperature fuse that has a simplified structure and can be produced in large quantities at low cost. This will be explained in detail below with reference to the drawings.

FIG. 1 is a cross-sectional view of an embodiment of a temperature fuse according to the present invention before blowing out, and FIG. 2 is a cross-sectional view after blowing out the same.

In Fig. 1, one terminal 4' is attached to the closed side of a cylindrical metal case 5 with good thermal conductivity that is open at one end, and the terminal 4' is made smaller than the inner diameter of the metal case 5 and melted at a certain temperature or higher. A cylindrical pellet 1 made by compressing an insulating organic substance, the outer periphery of which is coated with a metal foil 2 made of silver, copper, aluminum, etc. having good electrical conductivity, is inserted into the metal case 5, and the terminal is inserted into the metal case 5. 4' and one side of the metal foil 2 are brought into contact.

In order to maintain sufficient contact with one surface of the cylindrical metal foil 2, the bottom of the metal case 5 is desirably finished horizontally without any irregularities.

Next, the connector 3 is inserted into the case 5 so that the bottom surface 3a of the cylindrical connector 3 made of silver, copper, etc. with good electrical conductivity is in contact with the other surface of the cylindrical metal foil 2. Similarly, the case 5 is placed so that the spring 6 is brought into contact with the bottom surface 3a of the connector 3.
The hole 7 in the shaft core of an insulator 7 made of an insulator or resin molded material, etc., has a hole 7b in the shaft core and a recess 7a in which one side of the spring 6 can be fixed.
The other terminal 4 having the collar 4a is inserted into the metal case 5.

At this time, the tip of the terminal 4 is connected to the tip 3b of the connector 3.
The spring 6 is in a compressed state.

In this state, the open end of the metal case 5 is bent and fixed toward the insulator 7, and then sealed with resin 8 to complete the fabrication.

In the temperature fuse thus produced, a conductive path is formed from the terminal 4 through the connector 3, the metal foil 2, and the other terminal 4'.

When this temperature fuse is installed and used in electronic equipment,
When the temperature rises due to a circuit abnormality in an electronic device, the cylindrical pellet 1 made by compressing the insulating organic material melts, and the spring 6 presses the connector 3, resulting in a cylindrical pellet of the insulating organic material. The metal foil 2 covering the terminal 4 is crushed and deformed to move the connector 3, and the terminal 4 and the connector 3 are separated to open the circuit and prevent temperature rise.

In addition, cylindrical pellets 1 made of the above insulating organic material
When the metal foil 2 covering the metal foil 2 is crushed and deformed, a small hole is made in a part of the metal foil 2 to make it easier for the cylindrical pellet 1 made of the insulating organic substance to escape;
It is an effective means to color the surface of the metal foil 2 according to the type of insulating organic substance to avoid contamination.

The temperature fuse of the present invention having the structure as explained above with reference to the drawings has a structure in which the inner wall of the case is used as a conductive path by covering the surface of an insulating organic material with an erodible conductive metal foil. Compared to conventional products, not only can the number of component parts be reduced, but the machining accuracy of the component parts can be made rougher, so it can be produced at a lower cost.

In addition, an insulated type cannot be expected if the inner wall of the case is used as a conductive path, but since the case is not used as a conductive path in this invention, if an insulating case is used, it can be used as an insulated type. It is something that can be done.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an embodiment of the temperature fuse according to the present invention before blowing out, and FIG. 2 is a cross-sectional view after blowing out the same. 1...Insulating organic material (cylindrical pellet),
2...Good conductive metal foil, 3...Connector, 4゜4'...Terminal, 5...Case (metal case), 6 ······spring.

Claims (2)

[Scope of utility model registration request] (1) A cylindrical insulating organic substance that melts at a certain temperature or higher, whose outer periphery is partially covered with a highly conductive metal foil with small holes, is inserted into the case, and one terminal protrudes from inside the case. is brought into contact with one side of the metal foil, and the other terminal is brought into contact with a connector that contacts another side of the metal foil within the case, and the connector is further crimped onto the side of the metal foil. A temperature fuse characterized in that a spring is provided compressed in the case and acts in a direction to separate the connector from the other terminal. (2) A temperature fuse according to claim (1) of the utility model registration, which is formed by coloring a part of the surface of a metal foil.