JPH0425647Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Purpose of the Invention] Industrial Application Field The present invention relates to an apparatus for measuring the local current density of a surface to be treated which is subjected to an electrolytic treatment such as electroplating.

Prior Art When performing electrolytic treatments such as electroplating and electrolytic polishing, it is essential to adjust the current density of the surface to be treated within an appropriate range in order to obtain a good electrolytically treated surface. In order to know the current density in such electrolytic treatment, there is a method of calculating it from the area of the surface to be treated and the total current value. There is a problem in that the current is concentrated and only a small amount of current flows to the recesses or the back surface, so it is not possible to obtain a good electrolytically treated surface just by knowing the average current density as described above.

Therefore, when performing electrolytic treatment, it would be possible to know the local current density at different locations on the contact surface between the conductor to be treated and the electrolytic bath.
This should make it possible to perform electrolytic treatment efficiently and with excellent results by adjusting the electrolytic treatment conditions, the shape of the counter electrode, the relative positional relationship with the counter electrode, etc. However, even if there is a laboratory measurement method for determining the local current density of a surface in contact with a liquid, the reality is that there is still no measurement method that can be used industrially at operational sites. Ta.

On the other hand, one of the inventors of the present invention proposed a bipolar electrode type sensor in which a pair of mutually insulated conductor electrodes are arranged facing each other at a predetermined distance, and the sensor is placed close to the wetted surface of the conductor to be measured for current density. The sensor is placed in an electrolytic solution, and the potential gradient proportional to the current density in the solution generated by the current flowing through the electrolytic solution is detected as the potential difference between the electrodes of the sensor. The current density in the liquid near the liquid contact surface of the conductor to be measured is determined by substituting it into the potential difference-current density function obtained by measuring the liquid, and from this, the current passing through a specific point on the liquid contact surface is determined. It has been found that a means for approximately measuring the density of is industrially practical. He then invented a current density measuring device based on this principle and filed a separate patent application (Japanese Patent Laid-Open No. 62-27655).

Problems to be Solved This current density measuring device includes a sensor having a conductor disposed at its tip facing each other at a distance, an electric wire that derives the potential difference between the conductors as a signal, and an output that amplifies and displays the signal. It consists of equipment. and,
The measurement accuracy of the current gradient obtained by such a measuring device is determined by fixing the electrode attached to the sensor in a position that maximizes the potential gradient at a position close to the wetted surface of the conductor to be measured. This can only be ensured by implementing the following.

However, the shape of the conductor to be measured is not necessarily simple, and positioning the sensor is not easy when trying to accurately measure current density at many parts of a conductor with a complex surface shape. Furthermore, it is not easy to fix the sensor in a position where the potential gradient is maximum, and in some cases, it has been impossible to even bring the electrode of the sensor close to the part to be measured.

Since the wetted electrode is used by being immersed in the electrolyte, it must not be easily corroded by the electrolyte, but if it is made of a corrosion-resistant metal such as platinum, it is expensive. In addition, in some cases, errors may occur in the measured values due to the influence of hydrogen overvoltage. Furthermore, if the electrode is made of a metal that will not contaminate the electrolyte even if the electrode in contact with the liquid dissolves, that is, the same type of metal as the ions in the electrolyte, there will be no measurement error as described above, but the electrolyte There is an inconvenience that different current density measurement sensors must be prepared for each type.

Therefore, the present invention eliminates the disadvantage of having to prepare current density measurement sensors with electrode shapes and materials that differ depending on the shape of the conductor to be measured and the type of electrolyte. The present invention aims to provide an economical and flexible current density measurement sensor that can be easily adapted to various measurement objects.

[Structure of the idea]

Means for Solving the Problems The object of the present invention as described above is to provide two wetted electrodes insulated from each other at the tip of an insulating cylindrical body. A conductor characterized in that respective liquid contact surfaces are arranged opposite each other at a predetermined distance apart, and the tip portion provided with the liquid contact electrode is configured to be detachable from the main body of the cylindrical body. This is achieved by using a sensor for measuring the current density of the surface in contact with the liquid.

Hereinafter, the sensor of the present invention will be explained with reference to the drawings. 1 is the main body of the electrically insulating cylindrical body, and 2 is the tip thereof. Two liquid contact electrodes 3, 3 are provided in the tip part 2, penetrating from the front to the rear in parallel with each other, and the front exposed parts 3a, 3a form a liquid contact part, and the rear exposed parts 3a, 3a form a liquid contact part. The portions 3b, 3b form male terminal portions. The distance between the wetted parts 3a, 3a is
For example, it is 5mm. Further, the main body part 1 is a hollow cylinder, and a two-core insulated wire 4 is provided through the internal space. The tip of each core wire is connected to female terminal portions 4a, 4a provided inside the tip of the main body 1, so that the electrode potential can be transmitted to an external meter.

The female terminal portion 4 inside the tip of the main body portion 1 like this
a, 4a and male terminal portions 3b, 3b on the rear surface of the tip portion 2
forms a removable connector, and a sealing member, such as an O-ring, is installed at the fitting part of the main body 1 and tip 2, which corresponds to the connector housing, to prevent electrolyte from entering. Of course, there is a

Function Since the current density measurement sensor of the present invention is configured as described above, the tip portion 2 is connected to the liquid contact electrodes 3, 3.
The entire tip can be removed from the main body 1, and another tip provided with a wetted electrode of a different shape and material can be attached in its place and used as is for the next measurement.

[Effect of idea]

As explained above, the sensor for measuring current density on the surface of a conductor in contact with liquid according to the present invention can be obtained by preparing the tip of a cylindrical body provided with electrodes in contact with liquid of different shapes and materials. Measurements corresponding to various different measurement conditions can be performed using only one sensor body, which not only facilitates and speeds up the measurement operation but also has the advantage of being economical.

[Brief explanation of drawings]

The drawing is a partially cutaway front view showing the structure of the sensor for measuring current density on the surface of a conductor in contact with liquid according to the present invention. DESCRIPTION OF SYMBOLS 1... Cylindrical body main part, 2... Cylindrical body tip part, 3
...Wetted electrode, 4...Insulated wire.

Claims (1)

[Scope of utility model registration request] Two liquid contact electrodes are provided at the tip of an insulating cylindrical body insulated from each other. A sensor for measuring current density on a surface of a conductor in contact with liquid, characterized in that the tip portion provided with a liquid electrode is configured to be detachable from the main portion of the cylindrical body.