JPS5919330Y2 - battery safety valve device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a safety valve device for a battery, and its purpose is to improve accuracy.

An embodiment of the present invention will be described below in detail with reference to FIGS. 1 and 2. Reference numeral 1 denotes a sealing lid equipped with a safety valve device according to the present invention, and a lid plate 2 in which a valve hole 21 is bored; It consists of a dish-shaped terminal plate 3 which has a gas vent hole 31 and is caulked to the bent edge 22 of the cover plate 2, and a valve chamber 4 is formed inside.

Reference numeral 5 denotes a bottomed cylindrical elastic body interposed in the valve chamber 4 (see FIG. 2), which is made of polypropylene resin, for example, and has a collar held between the lid plate 2 and the terminal plate 3. Rim 5
1, and a bottom portion formed of a thin layer portion 52 that constantly closes the valve hole 21 of the lid plate 2.

6 is a cutting edge facing the thin layer portion 52 of the elastic body 5;
It is formed by bending a part of the terminal plate 3 inward.

The sealing lid 1 equipped with such a safety valve device is airtightly and liquid-tightly attached to the opening of the outer wire 8 into which the electrode group 7 is inserted via the insulating backing 9.

To explain the operation of the safety valve device, when the internal pressure of the battery increases due to an internal short circuit or the like, the thin layer portion 52 of the elastic body 5 bends upward as shown by the broken line in FIG. The gas inside the battery is discharged into the atmosphere from the gas vent hole 31 through the valve chamber 4, thereby preventing the battery from being destroyed.

Now, as shown in FIG. 3, the conventional device of this type utilizes a thin resin plate 5' as an elastic body, and its end is connected to the bent edge of the cover plate 2 together with the end of the dish-shaped terminal plate 3. The structure was such that the thin plate 5' was installed by crimping, but in this case, the pressure during crimping caused the center of the thin plate 5' to warp, resulting in the thin plate 5' not touching the cutting blade 6 even in normal conditions. There is a risk that the thin layer plate 5' and the cover plate 2 may be damaged due to the warping of the thin layer plate, and even when gas inside the battery starts to be generated, Valve hole 2 of thin plate 5'
1, the gas would reach a portion other than the portion facing 1, making it impossible to accurately detect the predetermined pressure, resulting in a problem in terms of accuracy.

On the other hand, according to the device of the present invention, since the elastic body incorporated into the valve chamber has a bottomed cylindrical shape with a flange, the crimping pressure when crimping the flange together with the end of the terminal plate is applied to the cylinder wall. Since it is absorbed and does not act on the thin layer that blocks the valve hole of the cover plate, the thin layer does not warp, and therefore the cover plate and the thin layer always maintain high adhesion. A high-precision safety valve can be obtained.

Furthermore, as shown in Fig. 1, if the elastic body is interposed in the valve chamber under compression, it has the advantage of preventing leakage of the electrolyte flowing along the joint surfaces between the elastic body, the cover plate, and the terminal plate. It is.

[Brief explanation of the drawing]

Figures 1 and 2 relate to the present invention; Figure 1 is an enlarged sectional view of the main part of a battery equipped with the safety valve device of the present invention, Figure 2 is a perspective view of the elastic body, and Figure 3 is a conventional safety valve device. FIG. 2 shows enlarged cross-sectional views of essential parts of batteries equipped with the following. 2...Lid plate, 21...Valve hole, 22...
...Folded edge, 3...Dish-shaped terminal plate, 4...
...Valve chamber, 5...Bottomed cylindrical elastic body, 51.
...Brim edge, 52...Thin layer part, 6...
...Cutting blade.

Claims (1)

[Scope of Claim for Utility Model Registration] ■ A flange sandwiched between the lid plate and the terminal plate in a valve chamber formed by a lid plate with a valve hole and a dish-shaped terminal plate with a gas vent hole; A bottomed cylindrical elastic body having a bottom formed of a thin layer that constantly closes the valve hole is interposed, and a cutting blade protruding from the inner bottom surface of the terminal plate is attached to the thin layer of the elastic body. A safety valve device for facing batteries. (2) The battery safety valve device according to claim (2), wherein the elastic body is interposed in the valve chamber under compression.