JP3136896B2 - Thermal battery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal battery provided with a piezoelectric ignition plug. In particular, the present invention relates to a structure of a glass insulating portion of a hermetic seal input terminal of a piezoelectric ignition plug.

[0002]

2. Description of the Related Art A thermal battery is inactive at room temperature, but becomes active when heated to a high temperature and can supply electric power to the outside, and is a kind of storage battery. Therefore, the storage life is very good, and it can be used without any change in characteristics even after storage for 5 to 10 years. Further, since the electrode is operated at a high temperature, the electrode reaction easily proceeds and has a high output characteristic, so that it is used as a power source for various defense devices such as missiles and guidance devices and an emergency power source.

A conventional thermal battery using a piezoelectric ignition plug will be described with reference to FIG. In FIG. 2, an input terminal 3 of a hermetic seal and a glass insulating part 4 are provided on an exterior lid 2. A piezoelectric ignition plug 7 is provided inside the battery, and includes an ignition terminal 5 and an ignition agent 6.

As an ignition mechanism, when an external pressure is applied to the piezoelectric activation device 1 mounted outside the battery, high voltage energy is discharged at the ignition terminal 5 of the piezoelectric ignition plug through the input terminal 3 of the hermetic seal. The high voltage energy burns the igniter 6 to activate it as a thermal battery.

[0005]

However, in the above-mentioned conventional structure, the glass insulation portion of the hermetic seal has a glass insulation distance of 1.5 mm or less.
High voltage energy from the piezoelectric activation device caused a leak in the glass insulation of the hermetic seal, and high voltage energy could not be supplied to the ignition terminal of the piezoelectric ignition plug, and the ignition did not occur, resulting in poor ignition reliability. .

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. By making the glass insulation distance between the ignition terminal of the piezoelectric spark plug and the glass insulation portion a certain distance or more, the leakage of the glass insulation portion due to high voltage energy is prevented. An object of the present invention is to provide a thermal battery provided with a piezoelectric ignition plug with high reliability of prevention and ignition.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is to prevent a glass insulation portion of a hermetic seal from being leaked by making the glass insulation distance of the glass insulation portion a predetermined distance or more, and to reduce the piezoelectricity of the glass insulation portion. It is characterized in that ignition reliability is improved by supplying high voltage energy to the ignition plug.

[0008]

In this manner, by setting the glass insulation distance of the hermetic seal to a certain distance or more, high-voltage energy from the piezoelectric starting device does not leak in the glass insulation portion,
High voltage energy is supplied to the piezoelectric ignition plug, and ignition reliability can be improved.

[0009]

An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a sectional view of an ignition mechanism of a thermal battery using a piezoelectric ignition plug.

In FIG. 1, reference numeral 1 denotes a piezoelectric starting device which generates a high voltage, 2 denotes a thermal battery outer cover, 3 denotes an input terminal of a hermetic seal, and 4 denotes a glass insulating portion described later. Reference numeral 5 denotes an ignition terminal for discharging high-voltage energy from the piezoelectric activation device. The distance A between the ignition terminals is 0.3 mm to 0.6 mm, which is a conventional distance. Assuming that the glass insulation distance is B, the glass insulation distance B is at least five times the distance A between the ignition terminals, which is the discharge distance of the ignition terminal of the piezoelectric ignition plug.
Was ensured. FIG. 3 shows the relationship between the ratio of the distance between the ignition terminals to be discharged and the glass insulation distance of the glass insulation portion, and the ignition rate of the piezoelectric ignition plug when high-voltage energy is applied. As shown in FIG. 3, it is understood that the ignitability of the piezoelectric spark plug is improved as the ratio between the distance between the ignition terminals and the glass insulation distance of the glass insulation part is increased. When the ratio becomes 5 times or more, the ignition rate becomes 100%. In addition, it is understood that the smaller the ratio is, the lower the ignitability is.
This is because the rate of leakage in the glass insulating portion of the hermetic seal is increasing, and it is becoming difficult to supply high-voltage energy to the piezoelectric ignition plug. Also,
Similar results were confirmed for a piezoelectric ignition plug having a distance between the ignition terminals of 0.2 to 1.0 mm.

[0012]

As can be understood from the above description, by setting the glass insulation distance of the hermetic seal portion at least five times as large as the distance between the ignition terminals of the piezoelectric ignition plug, it is possible to prevent leakage of the hermetic seal portion, By improving the ignitability of the ignition plug, it is possible to provide a thermal battery including a highly reliable piezoelectric ignition plug.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an ignition mechanism of a thermal battery having a piezoelectric ignition plug.

FIG. 2 is a cross-sectional view of a thermal battery having a piezoelectric ignition plug.

FIG. 3 is a diagram showing the relationship between the ratio of the distance between the terminals of the ignition terminal and the insulation distance of the glass insulation portion and the ignition rate of the piezoelectric ignition plug.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Piezoelectric starter 2 Exterior cover 3 Hermetic seal input terminal 4 Hermetic seal glass insulation part 5 Ignition terminal 6 Ignition agent 7 Piezoelectric ignition plug A Distance between ignition terminals B Glass insulation distance

──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Teruo Yamane 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. In-company (72) Inventor Kazuya Omichi 1006 Kadoma, Kazuma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. (58) Field surveyed (Int. Cl. ⁷ , DB name) H01M 6/36 JICST file (JOIS)

Claims (1)

(57) [Claims] 1. A thermal battery having a piezoelectric ignition plug ignited by a piezoelectric activation device, wherein the glass insulation distance of the glass insulation portion of the hermetic seal input terminal of the piezoelectric ignition plug is set between the ignition terminals of the piezoelectric ignition plug. A thermal battery that is at least five times the distance.