JPH05281173A - Coating film deterioration measurement probe - Google Patents

Abstract

(57) [Summary] [Purpose] It is possible to prevent external noise from entering and to use it without causing problems such as poor insulation and poor continuity when the probe body container is washed with water. [Structure] A hole 52 is formed in a probe main body container 43, one end of a measurement cable 55 is inserted into the hole 52 to be connected to a measurement electrode 44, and the measurement cable 55 in this state is watertightly fixed. The probe main body container 43 is integrated with the probe main body container 43, while the detachable connector 64 is provided at the other end of the measurement cable 55 so that the connecting portion of the measurement cable 55 to the measurement electrode 44 is connected to the probe main body container 4.
It was kept in the hole 52 of No. 3 so as not to be exposed to the air, and the water and the rest of the conductive gel 45 when the probe body container 43 was washed with water could be prevented from adhering thereto.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating film deterioration measuring probe for electrically measuring deterioration of a coating film applied on a metal surface.

[0002]

2. Description of the Related Art Conventionally, as a method for electrically measuring the deterioration of a coating film applied to a metal surface, a structure shown in FIG. 3 has been implemented.

That is, a measurement electrode 4 such as an aluminum foil is brought into contact with a coating film 2 to be measured applied on a base metal 1 from above via a conductive gel 3, and in this state, an AC power source 5 is used to form a base material. An alternating voltage is applied between the metal 1 and the measuring electrode 4, the current value at this time is read from the ammeter 6 and the voltage value is read from the voltmeter 7, respectively, and the impedance of the coating film 2 to be measured is read from these values. Ask.

After obtaining the impedance of the coating film 2 to be measured in this way, a Bode diagram in which the absolute value of the impedance with respect to the frequency is plotted, or a Nyquist diagram in which the impedance is represented by a real part and an imaginary part is created. Then, the degree of deterioration of the coating film 2 to be measured is estimated.
On the other hand, in order to improve the measurement accuracy, a measurement method using a coating film deterioration measurement probe shown in FIG. 4 has been considered.

In this case, a probe electrode container 11 is provided with a measuring electrode 12 inside the probe main body container 11, and a sponge 13 is loaded in the probe body container 11 so as to come into contact therewith. Gel 14 is impregnated. In addition, the sponge 13 has a probe body container 11
A convex surface portion 15 protruding outward and downward is formed. By pressing the convex surface portion 15 against the measured coating film 17 applied to the base metal 16, the conductive gel 14 is brought into close contact with the measured coating film 17. It has become so.

Further, the probe body container 11 is provided with a connection terminal 18 penetrating the inside and outside thereof. The inner end of the connection terminal 18 is electrically connected to the measuring electrode 12, and the measuring cable 19 is connected to the outer end by a clip 20 at one end. In addition, the measurement cable 19 has a preamplifier (not shown) whose other end (not shown) is connected to an impedance measuring device.
It is designed to be connected to. In addition, a male screw portion 21 is formed on the outer peripheral portion of the probe body container 11,
A pressing ring 23 having a magnet 22 is screwed into this.

With such a structure, when measuring the deterioration of the coating film, the pressing ring 23 is screwed along the male screw portion 21, and the magnetic attraction force of the magnet 22 to the base metal 16 causes the sponge 13 (the conductive gel 14). ) Is brought into close contact with the coating film 17 to be measured, while the measuring cable 19 connected to the preamplifier is connected to the connecting terminal 18 by the clip 20.
And another measuring cable 24, which is also connected to the preamplifier, is connected to the base metal 16. And
In that state, from the impedance measuring device to the preamplifier,
An impedance is measured by applying an AC voltage between the measuring electrode 12 and the base metal 16 via the measuring cables 19 and 24.

However, this device has a problem that since the connection portion of the measuring cable 19 by the clip 20 is exposed to the air, external noise is mixed from there and high measurement accuracy cannot be obtained.

Therefore, it is further considered to configure as shown in FIG. That is, although basically the same as that shown in FIG. 4, the probe main body container 11 is provided with a connector 31 instead of the connection terminal 18, for example, in the upper part, and the lower end portion of the center connection conductor 32 of the connector 31 is provided. Measurement electrode 12
And the upper end portion is projected onto the probe main body container 11 in the guide cylinder portion 33. On the other hand, the measurement cable 19 has the insertion connector 34 provided at one end thereof in the guide cylinder portion. It is inserted into 33 and is connected to the center connecting conductor 32.

According to this structure, the connecting portion of the measuring cable 19 to the connector center connecting conductor 32 is not exposed to the air, and external noise can be prevented from entering from there, so that high measuring accuracy can be obtained.

[0011]

In the case of the structure described above, the sponge 13 in the probe body container 11 is
It is designed to be taken out from a predetermined sponge storage container and loaded into the probe main body container 11 at each measurement, and after the measurement is completed, it is taken out from the probe main body container 11 and returned to the sponge storage container. .. For this reason, the conductive gel 14 impregnated in the sponge 13 remains attached to the inner surface of the probe body container 11 because the conductive gel 14 contains salt. Therefore, there is a risk that the probe body container 11 may be corroded. Therefore, after taking out the sponge 13, the inner surface of the probe main body container 11 is washed and washed with water, and then dried and stored.

However, in the case of the structure as shown in FIG. 5, when the probe main body container 11 is washed with water, the water and the rest of the conductive gel 14 enter the guide tube portion 33 of the connector 31 and are applied to the center connecting conductor 32. The conductor 32 is connected to the probe main body container 11 via the guide tube portion 33.
There is a problem of insulation failure such as electrical continuity.

Further, in this case, the center connecting conductor 32 is corroded by water or the remaining contact of the conductive gel 14 to cause poor continuity with respect to the measuring cable 19, resulting in a decrease in measurement accuracy.
In some cases, there is a problem that measurement becomes impossible.

The present invention has been made in view of the above-mentioned circumstances, and therefore an object thereof is not only to prevent mixing of external noise, but also to cause problems of insulation failure and conduction failure when the probe body container is washed with water. (EN) A probe for measuring deterioration of a coating film that can be used without causing it.

[0015]

In order to achieve the above object, in the coating film deterioration measuring probe of the present invention, an impregnating member impregnated with a conductive gel is loaded in a probe body container provided with a measuring electrode. Then, in the one constituted by connecting the measurement cable to the measurement electrode, a hole is formed in the probe main body container, and one end of the measurement cable is inserted into the hole to form the measurement electrode. It is characterized in that it is connected and the measurement cable in this state is watertightly fixed and integrated with the probe main body container, while a detachable connection portion is provided at the other end of the measurement cable.

[0016]

According to the above means, the connecting portion of the measuring cable to the measuring electrode is retained in the hole of the probe main body container so that it is not exposed to the air, and when the probe main body container is washed with water. It is also possible to avoid the adhesion of water and conductive gel.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. First, in FIG. 1, a base metal 41,
Also, the measured coating film 42 applied on the base metal 41 is shown.

On the other hand, the probe body container 43 is provided with a measuring electrode 44 on its inner peripheral surface. More specifically, the measuring electrode 44 is made of a material having small polarizability such as tin foil, and is provided on the inner peripheral surface of the probe main body container 43 by a method such as adhesion or plating.

An inside of the probe body container 43 is filled with an impregnating member, for example, a sponge 46 impregnated with the conductive gel 45, and the conductive gel 45 is brought into contact with the measuring electrode 44. The sponge 46 has a probe body container 43.
A convex surface portion 47 that protrudes outward and downward is formed. Further, a male screw portion 48 is formed on the outer peripheral portion of the lower portion of the probe body container 43, and a holding ring 50 having a magnet 49 is screwed into the male screw portion 48.

On the other hand, a shield case 51 is attached to the outer periphery of the upper portion of the probe body container 43. The shield case 51 is for preventing external noise from entering, and is made of, for example, an aluminum material, and the upper surface portion and each side surface portion are integrally formed.

A hole 52 reaching the measuring electrode 44 is formed in the center of the upper surface of the probe body container 43 in common with the shield case 51.
A fixture 53 is attached to the upper part of the with a plurality of screws 54.

On the other hand, the measuring cable 55 is
As shown in FIG. 2, an insulating coating 57 made of a material such as polyethylene is provided around a central conductor 56 made of, for example, a copper wire in the central portion, and the surrounding is surrounded by a copper mesh wire 58, The peripheral portion is covered with an insulating surface layer 59 such as rubber, and is a so-called shielded wire that is absorbed by the mesh wire 58 and does not reach the central conductor 57 even if external noise is mixed, and its length is not specified. Is about 50 to 100 [cm].

One end of such a measuring cable 55 is inserted into the hole 52 of the shield case 51 and the probe main body container 43 through the fixture 53, and the center conductor 56 is inserted.
Is connected to the measuring electrode 44 by a method such as soldering. Then, the connecting portion is sealed from the conductive gel 45 in the sponge 46 with a waterproof adhesive 60.

A similar adhesive 61 is also applied to the portion of the fixture 53 through which the measuring cable 55 is inserted to seal the measuring cable 55, and at the same time, the measuring cable 55 is fixed, and by extension, the probe main body container of the measuring cable 55. It is also integrated with 43. In addition, a similar adhesive 62 is applied to the contact portion of the fixture 53 with the shield case 51 for sealing.

In addition, FIG. 1 shows a preamplifier 63 connected to an impedance measuring device (not shown).
The other end of the measuring cable 55 is connected to this by a connector 64 as a detachable connecting portion, and another measuring cable 65 connected to the base metal 41 is connected to the preamplifier 63. The connection is made by 66.

With this structure, when measuring the deterioration of the coating film, the pressing ring 50 is screwed along the male screw portion 48, and the magnetic attraction force of the magnet 49 to the base metal 41 causes the sponge 46 (conductive gel 45). Is brought into close contact with the coating film 22 to be measured by the convex portion 47, while the other end of the measurement cable 55 is connected to the preamplifier 63, and the other measurement cable 65 is also connected to the preamplifier 63. Then, in that state, an AC voltage is applied between the measurement electrode 44 and the base metal 41 from the impedance measuring device via the preamplifier 63 and the measurement cables 55 and 65 to measure the impedance.

As described above, in this structure, one end of the measurement cable 55 is inserted into the hole 52 formed in the probe body container 43 and connected to the measurement electrode 44, and the measurement cable 55 in this state is shielded. The deterioration of the coating film 22 to be measured can be measured in a state where it is fixed to the probe body container 43 in a watertight manner through the case 51 and integrated with the probe body container 43. The connecting portion of the measuring cable 55 to the measuring electrode 44 is retained in the hole 52 of the probe main body container 43 and is not exposed to the air. Therefore, external noise is not mixed from there, and high precision is achieved. You can measure.

Further, after the measurement, when the inner surface of the probe main body container 43 from which the sponge 46 is taken out is washed with water, the remaining water or the conductive gel 45 remains at the connection portion of the measurement cable 55 to the measurement electrode 44. It is possible to avoid adhesion to the
The problem of conduction failure does not occur, and reliable and highly accurate measurement can be performed.

In the above embodiment, the case in which the fixture 53 is used in watertightly integrating the measurement cable 55 into the probe body container 43 has been described.
The measurement cable 55 may be water-tightly integrated with the probe main body container 43 by filling the hole 52 with an insulating material such as resin or rubber and solidifying it. In addition, the holes 52 may be formed in side surface portions other than the upper surface portion of the probe body container 43. Further, the shield case 51 may be formed by combining the upper surface portion and the side surface portions separately, and the shield case 51 may be replaced by an electromagnet to obtain a necessary shielding effect. However, a shield drive amplifier or the like may be separately provided.

[0030]

As is apparent from the above description, in the coating film deterioration measuring probe of the present invention, an impregnating member impregnated with a conductive gel is loaded in a probe body container provided with a measuring electrode, and the above measurement is conducted. In the one constituted by connecting the measurement cable to the measurement electrode, a hole is formed in the probe body container, and one end of the measurement cable is inserted into the hole to be connected to the measurement electrode. The measurement cable is fixed in a watertight manner to be integrated with the probe body container, while the other end of the measurement cable is provided with a detachable connection part, whereby external noise is mixed. It can be used without causing problems such as poor insulation and poor continuity when the probe body container is washed with water,
Therefore, it has an excellent effect that reliable and highly accurate measurement can be performed.

[Brief description of drawings]

FIG. 1 is an overall sectional view showing an embodiment of the present invention.

[Figure 2] Cross-sectional view of a single measurement cable

FIG. 3 is a view corresponding to FIG. 1 showing a conventional example.

FIG. 4 is a view corresponding to FIG. 1 showing a different conventional example.

FIG. 5 is a partial equivalent view of FIG. 1 showing still another conventional example.

[Explanation of symbols]

43 is a probe main body container, 44 is a measurement electrode, 45 is a conductive gel, 46 is a sponge (impregnation member), 52 is a hole, 5
Reference numeral 5 is a measuring cable, and 64 is a connector (connecting portion).

Claims (1)

[Claims] 1. A probe main body container comprising a probe main body container provided with a measurement electrode, an impregnating member impregnated with a conductive gel, and a measurement cable connected to the measurement electrode. Along with forming a hole, one end of the measurement cable is inserted into the hole and connected to the measurement electrode, and the measurement cable in this state is watertightly fixed and integrated with the probe body container, while the measurement is performed. A coating film deterioration measuring probe, wherein a detachable connecting portion is provided at the other end of the cable for use in coating.