JP2002257506A - Non-contact coating thickness measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-contact coating thickness measuring device to measure the coating thickness on a travelling metallic plate in an accurately inline state, by removing instability in deflection accuracy of a carrier roller and in the surface condition (color, inclination and roughness) of a coated film. SOLUTION: In this non-contact coating thickness measuring device 1, a measuring displacement gauge unit is formed by integrating an eddy current displacement gauge 13 to measure a distance from the surface of a metallic plate with a cofocal displacement gauge 14 to measure a distance from the surface of a coated film on the same line in the travelling direction of a metallic plate 11, and an encoders 17 for detecting a position in the width direction and an encoder 16 for detecting a position in the direction of rotation are mounted. The deflection of a metallic roller 15 and the dispersion of the reference position of the displacement gauges are compensated by these encoders 16, 17 and the displacement gauges 13, 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact film thickness measuring device for measuring a coating film thickness on a metal plate,
More specifically, the present invention relates to an in-line non-contact film thickness measuring device that feeds back a coating film thickness to a mounted coating machine.

[0002]

2. Description of the Related Art Conventionally, as a method for measuring the thickness of a coating film on a metal plate, for example, as disclosed in JP-A-6-229709, from a set reference position to a metal plate surface. And an eddy current measuring device for measuring the distance between the reference position and the coating film surface.
There is known a non-contact film thickness measuring method in which an optical measuring device using a light source wavelength of up to 350 μm is integrated, a difference between respective distances is calculated, and a thickness of a coating film is obtained.

[0003] As another method, there is a contact-type film thickness measuring method in which a coating film is partially cut off from a metal plate and the height from the surface of the metal plate to the surface of the coating film is mechanically contacted. .

[0004]

However, in the above prior art, when an optical displacement meter for measuring the reflection intensity in the former non-contact film thickness measuring method is used, the wavelength of the light source is affected by the color. Although the thickness is 200 to 350 μm, it is affected by the color, inclination and roughness of the coating film surface, so that the flatness of the substrate (corresponding to a metal plate) and the coating film surface and the roughness of the coating film surface Is often not constant,
In this case, there is a problem that a measurement error increases.

In the latter contact-type film thickness measuring method, in order to use the contact-type film thickness meter for measuring the coating film thickness of a metal plate coated on the entire surface, the coating film must be partially shaved after drying. In addition, measurement in the undried state is impossible, and when measurement is performed after drying, the feedback to the coating film thickness control unit is delayed, the yield rate is reduced, and shavings are generated and the cleanliness is reduced. This was inconvenient for the required coating equipment.

The present invention has been made to solve the above-mentioned problems of the prior art, and the object thereof is to determine the thickness of a coating film applied on a traveling metal plate, the deflection accuracy of a conveying roller, the coating accuracy, and the like. It is an object of the present invention to provide a non-contact film thickness measuring device for performing highly accurate in-line measurement in consideration of instability of a film surface state (color, inclination, roughness).

[0007]

In order to achieve the above object, according to the present invention, there is provided a method of coating a metal sheet on a metal plate running in contact with a rotating metal roller. A non-contact film thickness measuring device for measuring a film thickness in a non-contact manner, wherein a displacement gauge unit for measurement is an eddy current type measuring a distance from a surface of the metal plate on the same line in a running direction of the metal plate. The displacement meter and a confocal laser displacement meter that measures the distance from the coating film surface are integrated, and have a structure that can be moved while recognizing the position in the width direction by a width position detection encoder. At the side end of the roller, an encoder for detecting the rotational direction position for correcting the run-out error of the metal roller is mounted, and the encoder for detecting the width direction position, the encoder for detecting the rotational direction position, and the eddy current displacement meter are used. Correction value the distance to the metal roller surface from a reference position of the eddy current type displacement gauge metal roller entire 1
Is stored in advance as the correction value 2 for the confocal laser displacement meter, and the distance from the reference position to the surface of the metal plate is measured by the eddy current displacement meter.
The correction value 1 is subtracted from the value to obtain a measurement value 1, and the distance from the reference position to the surface of the coating film is measured at the same position as the measurement using a confocal laser displacement meter. Is subtracted to obtain a measured value 2, and the measured value 1 is subtracted from the measured value 2 to calculate the thickness of the coating film.

According to the first aspect of the present invention, the distance to the metal plate surface is measured by the eddy current type displacement meter,
The distance to the coating film surface is measured by a confocal laser displacement meter, and the coating film thickness is measured in a non-contact manner based on the difference between the measured values, and the width direction position detection encoder and rotation direction position detection encoder are used. By mounting, the correction value is calculated by the distance from the reference position of the eddy current type displacement meter of the entire metal roller to the surface of the metal roller to correct the coating film thickness. Surface condition (color,
It is possible to provide a non-contact film thickness measuring device that can measure stably and accurately without being affected by inclination and roughness.

According to the second aspect of the present invention, the specification of the width and thickness of the metal plate, the specification of the coating film thickness and the coating width, and the measuring range are separately provided, and the measurement data is input. 2. A non-contact film thickness measuring apparatus according to claim 1, wherein the feedback of the coating film thickness control to the coating apparatus and the detection of scratches and deformation of the metal plate are enabled by comparing. It is.

According to the second aspect of the present invention, an arithmetic unit is separately provided, in which the control of the coating film thickness is fed back to the mounted coating machine by inputting and comparing standard data, measurement data, and the like. A non-contact film thickness measuring device can be used.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. The present invention relates to a non-contact film thickness measuring device (1) for measuring the thickness of a coating film (12) on a traveling metal plate (11) as shown in the perspective view of FIG. A hoop (ring) -shaped metal plate (11) wound in contact with a rotating metal roller (15) is applied to form a coating film (12), and this coating film (12) is used as another transfer target. An in-line non-contact film thickness measuring device (1) installed in a coating machine for transferring to a body (not shown) and used for measuring and controlling the thickness of the coating film (12).

The non-contact film thickness measuring apparatus of the present invention (1)
As shown in FIG. 1, an eddy current type displacement meter (13) for measuring a distance to a surface of a metal plate (11) wound in contact with a metal roller (15) and a surface of a coating film (12). Confocal laser displacement meter (14) for measuring the distance of a metal plate (1)
In the running direction (P) of 1), they are arranged so as to be integrated on the same straight line, and furthermore, in the width direction of the metal plate (11) by a linear guide (19), a ball screw (10), and a servomotor (18). It has a structure that can be moved.

[0013] The present invention is also intended to correct the run-out error of the metal roller (15) and the variation of the eddy current displacement meter (13) and the reference position of the confocal type laser displacement meter (14) depending on the location, thereby improving the measurement accuracy. The encoder (16) for detecting the position in the rotational direction and the encoder (17) for detecting the position in the width direction of the metal plate (11) are mounted. The correction value is measured and stored in advance without the metal plate (11).

Specifically, the correction value is determined by a metal plate (11).
In the state where there is no metal roller (15) from the reference position of the eddy current displacement meter (13) at each position of the entire area of the metal roller (15),
The distance to the surface of 5) is determined by the encoder for detecting the position in the rotational direction (16) and the encoder for detecting the position in the width direction (1).
7) and is stored as the correction value 1. The same is performed for the confocal laser displacement meter (14),
It is stored as the correction value 2.

Next, while the metal plate (11) is being coated, the eddy current displacement meter (1) is placed at the same position where the correction value 1 was obtained.
In 3), the distance from the reference position to the surface of the metal plate (11) is measured, and the correction value 1 is subtracted from it. This value becomes the thickness of the metal plate (11), and the measured value is 1.

Further, at the same position as the above measurement, the coating film (1) is moved from its reference position by the confocal laser displacement meter (14).
2) Measure the distance to the surface and subtract the correction value 2 from it. This value is the sum of the thicknesses of the metal plate (11) and the coating film (12), and is referred to as a measured value 2. The thickness of the coating film (12) can be obtained by subtracting the measurement value 1 from the measurement value 2, and the coating film thickness can be controlled by feeding back these data to the coating device.

In the above correction, the distance between the surface of the metal roller (15) and the surface of the coating film (12) is compared, so that the optical displacement meter used is not affected by color, reflectance, and surface roughness. The confocal laser displacement meter (1) used in the non-contact film thickness measuring device (1) of the present invention
4) is not affected by the color, the reflectance, and the surface roughness.

The difference between the correction value 2 and the correction value 1 is the difference between the reference position of the eddy current displacement meter (13) and the reference position of the confocal laser displacement meter (14). In addition, metal roller (1
5) By performing the correction value measurement at each position in the entire region, it is possible to correct the variation in the difference between the respective reference positions due to the parallelism error between the metal roller (15) and the linear guide (19). No delicate adjustments are required when assembling.

Further, a value obtained by subtracting a correction value of 1 from the distance from the reference position of the eddy current type displacement meter to the surface of the metal plate, that is, the plate thickness of the metal plate, is set forth in claim 2. By comparing the specifications of the thickness of the metal plate, it is possible to detect the scratches and deformation of the metal plate (11).

Non-contact film thickness measuring apparatus as described above (1)
For example, in order to apply a resist or the like to the above-mentioned hoop-shaped metal plate (11) to form a coating film (12), and transfer the coating film (12) to another base material to obtain a product. Coating /
The non-contact film thickness measuring device (1) which can be applied to a transfer machine and can be suitably used for a coating machine for a sheet-like metal plate (for example, an outer plate for automobiles).

[0021]

As described above, the present invention has the following effects. That is, the thickness of the coating film of the metal plate on the metal roller is used in combination with the eddy current displacement meter and the confocal laser displacement meter, and furthermore, the deflection of the metal roller, the variation in the reference positions of the two displacement meters, Correction to eliminate assembly errors of the moving mechanism of the meter enables accurate measurement without the need for delicate assembly and adjustment, and without being affected by the color, tilt, or roughness of the coating film surface. A non-contact film thickness measuring device can be obtained.

Further, since it is not affected by the state of the surface of the coating film as described above, the measurement can be performed even in an undried state.
Measurement is performed immediately after coating, and the result is fed back to the coating film thickness control unit, which has the effect of improving the product yield.

Furthermore, since the coating film surface is similarly unaffected, the displacement meter does not need to be calibrated even if the color of the coating material is changed, and the setup time can be shortened. Has the effect of improving.

Since the eddy current displacement meter and the confocal type laser displacement meter are non-contact type, they do not damage the coating film and do not generate dust due to the scraping of the coating film, so that the cleanliness is low. Enables commercialization in high environments.

Furthermore, by comparing the measured value of the thickness of the metal plate with the standard value inputted in advance, it is possible to detect the flaws and deformation of the metal plate, thereby contributing to the inspection of the product. There is.

Accordingly, the present invention relates to a non-contact film thickness measuring device for measuring a coating film thickness on a metal plate, and more particularly, to an in-line non-contact film thickness measuring device for feeding back the coating film thickness to a mounted coating machine. Demonstrate excellent practical effects.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an embodiment of a non-contact film thickness measuring apparatus according to the present invention.

[Explanation of symbols]

 1 Non-contact film thickness measuring device 10 Ball screw 11 Metal plate 12 Coating film 13 Eddy current displacement meter 14 Confocal laser displacement meter 15 Metal roller 16 Rotation Direction one detection encoder 17 ‥‥ Width direction one detection encoder 18 ‥‥ Servo motor 19 ガ イ ド Linear guide P ‥‥ Metal plate running direction W ‥‥ Metal plate width direction

Claims (2)

[The claims] 1. A non-contact film thickness measuring device for measuring a coating film thickness applied on a metal plate running in contact with a rotating metal roller in a non-contact manner, comprising a displacement meter unit for measurement. The eddy current displacement meter that measures the distance from the surface of the metal plate and the confocal laser displacement meter that measures the distance from the surface of the coating film are integrated on the same line in the running direction of the metal plate, and the width is further integrated. It has a structure that can be moved while recognizing the position in the width direction by a direction position detection encoder, and a rotation direction position detection encoder for correcting a deflection error of the metal roller is attached to a side end of the metal roller. The distance from the reference position of the eddy current displacement meter over the entire metal roller to the surface of the metal roller is corrected by the width direction position detection encoder, the rotation direction position detection encoder, and the eddy current displacement meter. 1 is stored in advance, and the confocal laser displacement meter is also stored in advance as a correction value 2, and the distance from the reference position to the surface of the metal plate is measured by the eddy current displacement meter. The value 1 is subtracted to obtain a measurement value 1, and the distance from the reference position to the surface of the coating film is measured at the same position as the measurement using a confocal laser displacement meter, and then the correction 2 is subtracted from the measurement. A non-contact film thickness measuring device, wherein the thickness of the coating film is calculated by subtracting the measured value 1 from the measured value 2 as the value 2. 2. A standard for the width and thickness of the metal plate, a standard for the coating film thickness and a coating width, and a measuring range are separately input to an arithmetic unit, and measurement data is input and compared. 2. The non-contact thickness measuring device according to claim 1, wherein feedback of control of the coating thickness to the coating device and detection of scratches and deformation of the metal plate are enabled.