JPS6029730Y2 - silver chloride electrode - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a silver chloride electrode used as a reference electrode or an internal electrode of a measuring electrode used in measurements such as a PH meter, redox potentiometer, or ion concentration meter.

FIG. 1 is an explanatory diagram of the structure of an embodiment of a comparison electrode using a conventionally commonly used silver chloride internal electrode.

In the figure, 1 is a glass tube with a double tube structure, 2 is an electrode body provided at the tip of the inner tube 11 of the glass tube 1,
In this case, silver wire is used.

3 is a silver chloride layer coated on the electrode body 2.

Reference numeral 4 denotes a cylindrical liquid junction provided at the tip of the outer tube 12 of the glass tube 1, and in this case, ceramic is used.

Reference numeral 5 denotes a support portion for fixing the liquid junction portion 4 to the glass tube 1, and in this case, silicone rubber is used.

Reference numeral 6 indicates an internal liquid filled in the glass tube 1, and in this case, a potassium chloride solution is used.

7 is a lead for taking out electromotive force.

In the above configuration, an electrode body 2 made of a silver wire coated with a silver chloride layer 3 is spread in an internal liquid 6 made of a potassium chloride solution of a certain concentration, and a certain electromotive force is obtained.

In this case, since pure silver chloride is an insulator, when the silver chloride layer 3 is coated on the electrode body 2, the resistance increases and it floats from the ground during potential measurement, making the measurement unstable. The measurement error will be large.

If the thickness of the coating layer is made thinner to lower the resistance, the silver chloride layer will be reduced, and the consumption and outflow of silver chloride will cause an abnormality in the generated electromotive force and shorten the life.

The present invention solves these problems.

An object of the present invention is to provide a silver chloride layer electrode that has low resistance, is stable, and allows accurate potential measurement.

FIG. 2 is an explanatory diagram of the configuration of an embodiment of the present invention.

In the figure, 1 is the electrode body made of silver wire.

As shown in the figure, 2 is a silver chloride layer coated on the tip of the electrode body 1.

Reference numeral 3 denotes a fibrous liquid junction member provided along the surface of the silver chloride layer 2 in the axial direction of the electrode body 1, and in this case, glass fiber is used.

Reference numeral 4 denotes a waterproof protective layer that covers the central portion of the liquid junction member 3 and the silver chloride layer, and in this case, a waterproof heat-shrinkable resin tube is used.

5 is an insulating coating that covers the silver wire 1, and in this case, like the protective layer 4, a heat-shrinkable resin tube is used.

In the device of the present invention having the above structure, since the protective layer 4 is provided, leakage and consumption of silver chloride is prevented, and the life of the electrode can be extended.

Furthermore, since the thickness of the coating can be made thinner, the resistance of the electrode can be lowered.

Furthermore, since both ends of the liquid junction member are not covered with the protective layer 4 and are exposed, the internal liquid 6 described in FIG.
The silver chloride layer 2 can be easily reached by capillarity.

Therefore, since the electrode of the present invention can be manufactured and stored in a dry state, it is possible to obtain an electrode with good workability and storage property.

In the above-mentioned embodiment, it has been explained that the liquid junction member 3 is made of glass fiber, but the liquid junction member 3 is not limited to this, and any fibrous material used for fishing line may be used.

Further, the silver chloride layer 2 may be a mixture of potassium chloride and silver chloride.

In this way, potassium chloride dissolves into the internal potassium chloride solution, causing minute cracks in the silver chloride layer 2, thereby lowering the resistance value of the entire electrode.

Furthermore, in the case of a mixture of potassium chloride and silver chloride, the internal liquid 6
If it is immersed in water for a long period of time, it will lose its mechanical strength and become easily broken, so in practice, the potassium chloride content should be 0.3 to 3%W.
t (0.57 to 5.6 mo1%) is desirable.

As explained above, according to the present invention, it is possible to realize a silver chloride electrode that has low resistance, is stable, and can accurately measure potential.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the construction of an embodiment of a comparison electrode using a silver chloride internal electrode that has been commonly used in the past, and FIG. 2 is an explanatory diagram of the construction of an embodiment of the present invention. 1... Electrode body, 2... Silver chloride layer, 3
...Liquid junction member, 4...Protective layer.

Claims (1)

[Scope of utility model registration request] A rod-shaped electrode body, a silver chloride layer coated on the tip of the electrode body, a fibrous liquid junction member provided on the silver chloride layer in the axial direction of the electrode body, and a center of the liquid junction member. and a protective layer covering the silver chloride layer.