JPH0634359A - Calibrating method for film thickness gauge - Google Patents

Abstract

PURPOSE:To facilitate key entries in the operation of setting the standard value and simplify calibrating of a film thickness gauge by reading the thickness value of a standard value measuring body into a computer while the measuring point is changed several times. CONSTITUTION:A film thickness gauge concerned is turned into the calibration mode, and a probe is touched with a standard value measuring body (reference board). The first thickness value is computed by a microcomputer, and the obtained value from computation is given on a display part. An up-down key is pressed according to the obtained value being higher or lower than the standard value to make setting so that the displayed value is identical to the standard value, and the value is read into the microcomputer. The second thickness value is computed by the microcomputer while the measuring point on the reference board is changed, and the acquired value is displayed. If the up-down key is pressed until the value attains the set value, the displayed value will stop at the set value, and the standard value is read into the microcomputer. T After this, thickness values are read into the microcomputer several times while the measuring point is changed, and the calibration is completed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for calibrating a film thickness meter used for measuring the film thickness of a coating coated on a metal surface.

[0002]

2. Description of the Related Art In steel structures such as ships, bridges, automobiles, equipment, etc., the metal surface is coated and finished, but it is desirable that the coating film be finished to a thickness as uniform as possible. If the coating film thickness is below a predetermined value, the coating film is likely to peel off due to a change with time, which causes metal corrosion. Further, if the coating film is too thick, it is economically disadvantageous.

The coating of the steel structure as described above is carried out after the coating is completed in the case of one-time coating, and in the case of a plurality of coatings, at a point of time when the predetermined number of coatings are completed, an arbitrary plurality of locations are selected to form a film. Measure the film thickness using a thickness meter.

Generally, a film thickness meter is composed of a probe which is brought into close contact with a coated surface, a calculation section which calculates a signal detected by this probe, and a display section which displays a result calculated by this calculation section. The film thickness meter is roughly classified into an electromagnetic type and an eddy current type. In the former electromagnetic type film thickness meter, when an AC voltage is applied to the coil containing the iron core and the tip of the iron core is brought close to the object to be measured (for example, iron) through the coating film, the tip of the iron core and the object to be measured are separated. The inductance of the coil changes in response to a slight change in distance. This change is calculated by the calculation unit to measure the thickness of the coating film thickness on the surface of the measured object. The latter eddy-current type film thickness meter uses the electrical correlation between the magnitude of the eddy current induced on the metal surface by the high-frequency electric field and the thickness of the surface film to perform surface treatment on a metal substrate other than iron. The thickness of the insulating film is measured.

[0005]

The above-mentioned film thickness meter employs means for first calibrating with a standard thickness plate and then measuring the thickness of the coated surface. However, when calibrating with the standard thickness plate, the vertical movement keys of the film thickness meter must be operated so that the numerical value displayed on the display unit reaches the standard value.

This operation is extremely delicate, and it is difficult to adjust it to the standard value, and if it exceeds the standard value, it has to be restored by the key operation. Since such a procedure is repeated about 10 times to set the standard value in the film thickness meter, there is a problem that it takes a considerable amount of time to calibrate the film thickness meter and requires considerable skill. In order to solve the above problems, the present invention provides a method for calibrating a film thickness meter, which enables easy operation of keys in standard value setting operation and easy calibration of the film thickness meter. To aim.

[0007]

In order to achieve the above object, the present invention provides a film thickness meter for calculating a thickness value of an object to be measured detected by a probe by a microcomputer and displaying the calculated value on a display unit. When measuring the thickness by the, set the film thickness meter to the calibration mode, measure the probe on the standard value measuring object, calculate the first thickness value by the microcomputer, and then display the calculated value on the display unit. Depending on whether the display value is higher or lower than the standard value, the up / down movement key is operated to set the display value to the standard value, the value is read by the microcomputer, and then the second time The thickness value is input to the microcomputer by changing the measurement point of the standard value measurement object, the thickness value is calculated, and when the calculated value is displayed on the display unit, the up / down movement key is pressed until the calculated value is set. To operate , Stopped in operation value the value of the display unit is set, the standard value is read into the microcomputer,
After that, the film thickness meter is calibrated several times so that the thickness of the film can be read by a microcomputer by changing the measurement point of the standard value measuring body.

[0008]

The microcomputer calculates the first thickness value of the standard value measuring body and displays it on the display unit. If the displayed value is different from the standard value, use the up / down movement keys to bring it to the standard value. Next, the second thickness value measurement is performed.
If the displayed value at that time is different from the standard value,
When the up / down movement key is operated to change the displayed value and the standard value of the first time is reached, the displayed value higher or lower than that value does not change. Then, the same operation is repeated several times to complete the calibration.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described in detail below with reference to the drawings. In FIG. 1, first, in order to calibrate the film thickness meter, the calibration mode in the film thickness meter (not shown) is operated to enter the calibration mode of step S1. Then, a probe (not shown) is brought into contact with a reference plate (not shown) in order to obtain a standard value for calibration of the film thickness meter. This step is step S2.

Here, it is assumed that the reference plate is 100 μm. The measured value of the reference plate detected by the probe is read into the microcomputer. The microcomputer has
A memory table corresponding to the thickness of the reference plate is prepared, and the value detected by the probe and the value in the memory table are calculated and displayed on the display unit, for example, 98 μm. This step is step S3.

Since 98 μm is displayed on the display unit, the upper key is operated at step S4 so that the displayed value becomes 100 μm. At this time, the value in the memory table of the microcomputer moves to a value corresponding to 100 μm. When the operation of step S4 is completed, the process proceeds to step S5, and the probe is separated from the reference plate. Then, the flag is set to the value of the memory table. Next, the probe is brought into contact with the reference plate again by changing its position. This step is step S6. The calculated value at step S6 is 96
If it is μm, 96 μm is displayed in step S7.

At step S8, the up key is operated again to change the value on the display, and the value is changed to 10
At 0 μm, the displayed value no longer changes. This is because once the value is set to 100 μm, the value in the memory table stores this value and compares it with the value input from the key so that the key input value does not change any more. This step is step S9.
The calibration of the film thickness meter is completed by repeating the above operation several times. If the calibration is performed in this way, the calibration operation becomes extremely simple.

[0013]

According to the present invention described above, there is an advantage that the calibration operation of the film thickness meter can be simplified.

[Brief description of drawings]

FIG. 1 is a flowchart showing an embodiment of the present invention.

[Explanation of symbols]

 S1 Calibration mode step S2 Probe contact step S3 Display section step S4 Key operation step S5 Probe release step S6 Probe contact step S7 Display section step S8 Key operation step S9 Display value stop step

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[Procedure amendment]

[Submission date] March 8, 1993

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

Claims (1)

[Claims] 1. A film thickness meter is set to a calibration mode when the thickness value of the object to be measured detected by the probe is calculated by a microcomputer and the thickness is measured by a film thickness meter that displays the calculated value on a display unit. After that, the standard value measuring body measures the probe, the microcomputer calculates the first thickness value, and then the calculated value is displayed on the display unit. Depending on whether the displayed value is higher or lower than the standard value, The display value is set to the standard value by operating the dynamic keys, the value is read into the microcomputer, and then the second thickness value is changed by changing the measurement point of the standard value measurement object to the microcomputer. When you press the up / down key until the calculated value is displayed on the display and the calculated value is displayed, the value on the display will stop at the set value. The standard value is It is loaded on the micro computer,
A method of calibrating a film thickness meter, wherein the film thickness meter is calibrated by reading the thickness value several times after that in a microcomputer by changing the measurement point of the standard value measuring body.