JPS6239570Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a contact type temperature switch.

As a contact type temperature switch, as shown in FIG. 2, a conductive case 1' having a first lead conductor 2a' is used.
A second lead conductor 2b' is introduced into the case 1' through an insulator 3', a movable electrode 4' is provided inside the case, and the movable electrode 4' is fixed to the inner surface of the case 1' with a low melting point alloy 8'. It is known that a compression spring 5' is provided to separate the movable electrode 4' from the second lead conductor 2b' when the alloy 8' is melted, and the melting point of the low melting point alloy 8' is set to the operating temperature of the temperature switch. It is used by setting it to .

However, in manufacturing this temperature switch, the movable electrode must be fixed to the inner surface of the case with a low melting point alloy while the stress of the compression spring is applied to the movable electrode. However, if the stress of the compression spring is reduced, the separation performance of the movable electrode will inevitably deteriorate when the low melting point alloy is melted. It becomes difficult to temporarily fix the movable electrode.

The present invention provides a contact type temperature switch which is easy to temporarily fix and has excellent separation performance of the movable electrode.

That is, the contact type temperature switch according to the present invention has a second lead conductor inside a conductive case having a first lead conductor.
A lead conductor is introduced insulated from the case, a movable electrode is housed in the conductive case, the movable electrode is brought into contact with the inner surface of the case and the tip of the second lead conductor, and a low melting point is formed between the movable electrode and the inner surface of the case. Combined with alloy,
In a temperature switch in which a compression spring is provided in a conductive case to separate the movable electrode from the second lead conductor when the low melting point alloy is melted, the compression spring is provided with a memory alloy whose transformation temperature is lower than the melting point of the low melting point alloy. Furthermore, this structure is characterized in that it is provided with a magnet that causes a magnetic force that is slightly larger than the compressive stress of the memory alloy compression spring to act on the movable electrode against the stress.

The present invention will be explained below with reference to the drawings.

In FIG. 1, a conductive case 1 has a lid 11 (to which the case is soldered, for example), and a first lead conductor 2a is integrally provided with this lid. 2b is the second lead conductor, and the insulator 3
It is introduced into Case 1 via . 4 is a movable electrode. 5 is a spring made of memory alloy. 8 is a magnet attached to the movable electrode, 7 is a magnet fixed to the case, and the magnetic force acting between these magnets brings the movable electrode 4 into contact with the second lead conductor 2b against the compressive stress of the spring 5. be. 8
is a low melting point alloy that connects the movable electrode 4 to the inner surface of the case 1, and the martensitic transformation temperature of the memory alloy spring 5 is set lower than the melting point of the low melting point alloy 8.

When joining using this low melting point alloy, since the movable electrode is fixed by magnetic force, the joining can be easily performed.

In the above temperature switch, the memory alloy spring is heated to the martensitic transformation temperature before reaching the switch operating temperature, that is, the melting point of the low melting point alloy, so it will stretch to the original dimensional length that was memorized until then. When the low melting point alloy melts, the movable electrode can be quickly separated from the second lead conductor by the expansion of the spring. Therefore, even if the compressive stress of the memory alloy spring is small at a constant temperature lower than the martenside transformation temperature,
The separation characteristics of the movable electrode can be fully guaranteed. Also,
Because the compressive stress of memory alloy springs is small,
The movable electrode can be easily temporarily fixed by the low melting point alloy, and the magnet for obtaining the temporary fixing force can also be made smaller.

As mentioned above, the contact type temperature switch according to the present invention is excellent in both the separation performance of the movable electrode and the ease of assembly. Furthermore, before the low melting point alloy is melted, the compression spring made of the memory alloy is compressed to its original length, and the compressive stress of the spring can be sufficiently increased. Can be quickly separated from 2-lead conductors.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a contact type temperature switch according to the present invention, and FIG. 2 is an explanatory diagram showing a conventional temperature switch. In the figure, 1 is a conductive case, 2a and 2b are lead conductors, 3 is an insulator, 4 is a movable electrode, 5 is a memory alloy spring, 6 and 7 are magnets, and 8 is a low melting point alloy.

Claims (1)

[Scope of utility model registration request] A second lead conductor is introduced into a conductive case having a first lead conductor insulated from the case, a movable electrode is housed in the conductive case, and the movable electrode is brought into contact with the inner surface of the case and the tip of the second lead conductor. , a temperature switch in which the movable electrode and the inner surface of the case are connected by a low melting point alloy, and a compression spring is provided in the conductive case to separate the movable electrode from the second lead conductor when the low melting point alloy melts. A memory alloy whose transformation temperature is lower than the melting point of the low melting point alloy is used for the spring, and a magnet is provided that applies a magnetic force slightly larger than the compressive stress of the memory alloy compression spring to the movable electrode against the stress. A contact type temperature switch with special features.