JPS61121225A - Temperature fuse plug for high temperature - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a high-temperature fuse plug used for detecting abnormally high temperatures of 8oO°C or higher in automobile exhaust gas purification devices used in shock and vibration environments. It is related to.

Structure of a conventional example and its problems A conventional high-temperature fuse plug of this type will be explained with reference to FIGS. 1, 2, and 3.

Two heat-resistant metal wires 2 and a powdered insulating filler 3 are arranged as lead wires inside the heat-resistant metal tube 1. A tip is attached to one end of the two heat-resistant metal wires 2 protruding from one end of the heat-resistant metal tube 1. A fusible metal body 6 with a slit 4 disposed near the part and a flux 5 arranged around it is connected, and the other end of the fusible metal body 6 and the other end of the two heat-resistant metal wires 2 are connected to a heat-resistant metal body 6. The fusible metal body 6 and the connection part are inserted into the opening of the connection 7' and 9L heat-resistant metal cap 1o via the metal wire 8, and the heat-resistant metal cap 1o is closed.
The open end and the heat-resistant metal tube 1 are sealed and fixed by welding 11. Further, the other end of the heat-resistant metal tube 1 is provided with a heat-resistant sealing material 12.
At the same time, the protruding portion of the heat-resistant metal wire 2 connecting the heat-resistant metal wire 8 is welded 13 to the heat-resistant metal tube 1 to earth the body.

In this high temperature fuse plug, when the temperature rises above the melting point of the fusible metal body 6, the molten body 14 statically moves toward the heat-resistant metal wire 8 due to the effect of the slit 4, as shown in FIG. The melt 14 aggregates and becomes an electrically open circuit, but under strong vibrations and shocks, the melt 14 scatters and becomes spherical bodies 15, 15', forming an electrically reclosed circuit when placed in the position shown in Figure 3. There was a possibility that it would lose its function as a fuse plug.

Purpose of the Invention The present invention is intended to eliminate such conventional drawbacks.The bottom surface of a heat-resistant metal cap is coated with flux to prevent the molten material from scattering, and the bottom surface of the cap is wetted with molten material, and the cap is exposed to strong vibrations and shocks. The purpose of this is to prevent an electrically reclosed circuit even under the conditions.

Structure of the Invention In order to achieve the above object, the high temperature fuse plug of the present invention is provided with flux arranged on the bottom surface of a heat-resistant metal cap, and with one end of the connecting part of the fusible metal body abutted against the bottom surface of the heat-resistant metal cap. It is something to be placed.

With this configuration, when the temperature rises above the melting point of the fusible metal body, the molten body of the fusible metal body condenses on the bottom of the heat-resistant metal cap, and due to the effect of the pre-disposed flux, the molten body melts into the heat-resistant metal body. Since the bottom surface of the cage gets wet and becomes spherical and does not scatter under strong vibrations or shocks, there is no possibility that the fuse plug will become an electrical reclosing circuit. An example will be described using FIGS. 4 to 6.

A heat-resistant metal tube 16 in which two heat-resistant metal wires 1A and a powdered insulating filler 18 are arranged as lead wires inside the heat-resistant metal tube 16.
At one end of two heat-resistant metal wires 1a protruding from one end, a fusible metal body 21'' is connected, with an IJ 7 ) 19 arranged close to the end and a flux 20 arranged around it.
Connecting the other end of the fusible metal body 21 and the other tip of the two heat-resistant metal wires 1a via an L-shaped heat-resistant metal wire 22,
Insert the fusible metal body 21 and the connecting part into the opening of the heat-resistant metal cap 24 with the flux 23 arranged on the bottom until the connecting part abuts against the bottom of the heat-resistant metal cage 24, and then connect the open end of the heat-resistant metal cap 24 with the connecting part. The heat-resistant metal tube 16 is sealed and fixed by welding. The other end of the heat-resistant metal tube 16 is
At the same time, the protruding part of the heat-resistant metal wire 1A connecting the L-shaped heat-resistant metal wire 22 is sealed with the heat-resistant coil material 25, and the protruding part of the heat-resistant metal wire 1A is welded to the heat-resistant metal tube 16 to connect to the body ground. The structure is such that

According to this configuration, when the temperature rises above the melting point of the fusible metal body 21, the molten body 26 aggregates on the bottom surface of the heat-resistant metal cap 24 due to the effect of the slit 19 of the fusible metal body 21, and Due to the effect of the flux 23 which is the arrangement, the molten material 26 is welded to the bottom surface in a wet state, and there is no possibility that the molten material will be scattered due to strong vibrations or impact.

Effects of the Invention As described above, in the high-temperature fuse plug of the present invention, flux is arranged on the bottom surface of the heat-resistant metal cap, and one end of the connecting portion of the fusible metal body is placed in a state that it is in contact with the bottom surface of the heat-resistant metal cap. Therefore, when the molten metal body melts, the molten body condenses on the bottom of the heat-resistant metal cap, and does not scatter even if shock or vibration is applied. It is possible to prevent this from occurring, resulting in excellent reliability.

[Brief explanation of drawings]

Figure 1 is a sectional view of a conventional high temperature fuse plug, Figure 2
The figure is a cross-sectional view of a conventional high-temperature fuse plug when it is blown, FIG. 3 is a cross-sectional view of an example of a defect when a conventional high-temperature fuse plug is blown, and FIG. 4 is a high-temperature fuse plug of an embodiment of the present invention. A cross-sectional view of the temperature fuse plug, FIG. 5 is a cross-sectional view of the heat-resistant metal cap,
Fig. 6 is a cross-sectional view of an example of the same high abuse temperature fuse plug. Powdered insulating filling, 19.
...Slit, 20...Flux, 21.
... Fusible metal body, 22 ... Heat-resistant metal wire, 2
3...Flux, 24...Heat-resistant metal cap,
25... Heat resistant sealing material, 26... Molten body.

Claims (1)

[Claims] A metal wire is mechanically and electrically connected to both ends of the fusible metal body through a connection part for lead extraction, and a heat-resistant metal cap is placed to protect the fusible metal body and the connection part, and the bottom surface of this heat-resistant metal cap is A high-temperature thermal fuse plug that has flux applied to it, and one end of the connection part of the fusible metal body is placed against the bottom of the heat-resistant metal cap.