JP2001124541A - Thickness-measuring apparatus for sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply and quickly calibrate a plurality of sensors for thickness measurement. SOLUTION: In this thickness-measuring apparatus for a sheet, a plurality of freely movable sensors 11 for thickness measurement are arranged in measuring positions B, which face a sheet conveyance passage R. A plurality of measurable calibration positions C are formed on the same straight line L, along the sheet running direction (the direction of an arrow A) of the sheet conveyance passage R. The sensors 11 are arranged simultaneously in the calibration positions C. The measuring positions B are formed within a plurality of measurable regions B1, B2, B3, which are positioned along the traversing direction of the sheet conveyance passage R. The sensor 11 is arranged in every region B1, B2 or B3, in such a way that it can be moved back and fort within the measurable region. The sensors 11, 11, which are arranged in the adjacent measurable regions, are arranged simultaneously in the positions C which are formed in boundary region between the adjacent regions B1 and B2 or B2 and B3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a sheet thickness measuring apparatus for measuring the thickness of a coating film applied to a sheet such as a plastic film, a metal foil or paper, and the thickness of the sheet itself. .

[0002]

2. Description of the Related Art Conventionally, a thickness measuring device for a sheet is provided with one thickness measuring sensor which reciprocates along a width direction traversing a sheet conveying path, so that one whole region in the width direction of a running sheet is one. (Japanese Patent Application Laid-Open Nos. 4-161267 and 7-3).
No. 13917). Since this sheet thickness measuring device measures a traveling sheet with one thickness measuring sensor that reciprocates in the width direction, the sheet thickness is measured jerkyly, and an unmeasured area occurs. To reduce the non-measured area, it is conceivable to increase the reciprocating speed of the thickness measurement sensor, but there is a limit.

[0003]

As another countermeasure to reduce the non-measured area, it is conceivable to increase the number of thickness measuring sensors. However, when using a plurality of thickness measurement sensors, it is necessary to perform calibration between the sensors. However, since there is no optimal calibration method, it is substantially impossible to use a plurality of thickness measurement sensors. It was possible. Accordingly, an object of the present invention is to provide a sheet thickness measuring device that can easily and quickly perform calibration when using a plurality of thickness measuring sensors.

[0004]

In order to make it possible to calibrate a plurality of thickness measuring sensors simply and quickly, the means adopted by the present invention according to the present invention comprises a plurality of sensors arranged along a transverse direction of a sheet conveying path. Is provided, a plurality of calibration positions are provided on the same straight line along the sheet traveling direction of the sheet conveying path, and a thickness measurement sensor is arranged so as to be movable between the measurement position and the calibration position. A sheet thickness measuring device characterized in that a plurality of thickness measuring sensors can be arranged at the same time. In the present invention, a plurality of sensors are arranged at the same time at calibration positions provided on the same straight line along the sheet traveling direction, and the same position of the traveling sheet is measured by measuring the traveling sheet with these sensors. Calibration can be performed so that the measurement result of each sensor obtained by measurement is the same.

According to a second aspect of the present invention, the measurement position is a fixed position so that the plurality of fixed thickness measurement sensors can be calibrated simply and quickly. It is a thickness measuring device for use. According to the present invention, since a plurality of measuring sensors are provided along the transverse direction of the sheet conveying path, the thickness in the transverse direction can be measured simultaneously.

In order to easily and quickly calibrate a plurality of thickness measuring sensors which reciprocate in the width direction of the sheet conveying path, a means adopted by the present invention according to the present invention is as follows. 3. The sheet thickness measuring device according to claim 1, wherein the sheet thickness measuring device is arranged so as to be able to reciprocate with a moving tool along a transverse direction of the sheet conveying path from the measurement position to the calibration position. 4. According to the present invention, sensors reciprocating in adjacent measurement areas are simultaneously arranged at calibration positions provided on the same straight line along the sheet traveling direction,
By measuring the running sheet with both sensors, the portion of the sheet on the same straight line is measured along the sheet running direction, and the measurement result of each sensor obtained by measuring the same portion of the sheet becomes the same. Can be calibrated as follows.

The means adopted by the present invention according to the fourth aspect of the present invention is to easily and quickly calibrate the sensors, wherein the calibration circuit is connected to the thickness measuring sensor to output a measurement result. 4. A calibration circuit for automatically calibrating a measurement result of each sensor based on a measurement result measured by a plurality of sensors arranged at positions.
Or a sheet thickness measuring device according to item 3. According to the present invention, the measurement results of the plurality of sensors measured at the calibration position are automatically calibrated by the calibration circuit.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A thickness measuring apparatus for a sheet according to the present invention (hereinafter referred to as "the measuring apparatus of the present invention") will be described below based on an embodiment shown in the drawings. 1 to 3 show an embodiment of the measuring apparatus of the present invention. FIG. 1 is a right side view schematically showing the entire coating equipment 1 provided with the measuring apparatuses 6 and 8 of the present invention, and FIG. FIG. 3 is a plan view showing the arrangement of each sensor 11 of the inventive measuring devices 6 and 8, and FIG. 3 is a block diagram showing the contents of the measuring devices 6 and 8 of the present invention.

As shown in FIG. 1, the coating equipment 1 includes a drawing device 4, a coating device 5, and a wet coating film in order along the traveling direction of the sheet S from the unwinding device 2 to the winding device 3. The present invention comprises a measuring device 6 for the present invention, a drying device 7, a measuring device 8 for a dry film of the present invention, and a cooling device 9. Unwinding device 2
Is for rewinding the sheet S wound up in a roll shape. The pulling-out device 4 pulls out the sheet S unwound from the unwinding device 2 and supplies it to the coating device 5, and includes pull-out rolls 4a, 4a and a nip roll 4b which are forcibly driven. The sheet S pinched by the nip roll 4b is forcibly run. The coating device 5 includes a back-up roll 5
a and a coating head 5b, and a back-up roller 5a.
The coating liquid is applied to the surface of the sheet S that is supported and travels by the coating head 5b. Drying device 7
Is a type in which the sheet S passing through the drying chamber 7a is guided in a floating state or a roll supported state, and hot air is blown onto the sheet S passing from the nozzle 7b to dry the sheet S, and / or a lamp 7 is used.
A type in which radiant heat is applied to the sheet S passing from c, etc. is adopted. The cooling device 9 includes a cooling roll 9a and a nip roll 9b that are forcibly driven.
And the nip roll 9b forcibly runs the sheet S nipped by the nip roll 9b. The winding device 3 is for winding the coated sheet S into a roll.

The measuring devices 6 and 8 of the present invention are provided with a sheet S
A plurality of measurement positions B are provided along the transverse direction of the sheet conveying path R formed by the guide rolls 10 and 10 for guiding
A plurality of thickness measurement sensors 11 are movably arranged at each measurement position B, and a plurality of calibrations that can be measured on a virtual straight line L along the sheet traveling direction (arrow A direction) of the sheet transport path R. A position C is provided so that a plurality of sensors 11 moved to a plurality of calibration positions C can be simultaneously arranged in a line. As the sensor 11, a sensor for thickness measurement using infrared rays or β rays is selected.

The measuring device 6 according to the present invention has a measuring position B,
B and B are fixed positions set in advance, and the calibration positions C, C and C are fixed positions on a straight line L set in advance so that the sensor 11 can be moved between the measurement position B and the calibration position C. It is. A fixture 12 for fixing the sensor 11 is disposed at each of the measurement positions B and the constituent positions C. When the measurement position B and the calibration position C are shared, the sensor 11 does not move. The number of sensors 11 arranged at each measurement position B differs depending on the width of the sheet S,
The number is about 3 to 7. The movement of the sensor 11 is performed manually or automatically. When performing the automatic operation, the sensor 11 is attached to the moving tool guided by the guide rail, and the sensor 11 is reciprocated between the measurement position B and the calibration position C, although not shown. The measuring device 6 of the present invention measures the film thickness of the wet coating film (undried coating film) applied to the sheet S by the sensors 11 arranged at the respective measurement positions B. When the sensors 11 are calibrated, the sensors 11 are moved to the respective calibration positions C so that the plurality of sensors 11 are simultaneously arranged on the same straight line L, and the wet coating film of the running sheet S and the uncoated state are not applied. The sheet S is connected to these sensors 1
Calibrate by measuring at 1.

The measuring device 8 according to the present invention comprises a sheet conveying path R
Multiple measurable areas B1, divided along the transverse direction of
A measurement position is formed in each of B2 and B3, and the sensor 11 is arranged so as to reciprocate in each of the measurable areas B1, B2 and B3, and a boundary area between adjacent measurable areas B1 and B2 and between B2 and B3. , A pair of calibration positions C, C are formed on the same straight line L. The number of sections of the measurable area is
Although it differs depending on the size of the width dimension of the sheet S, it is about 3 to 7 sheets. Each sensor 11 is attached to a moving tool 14 guided by a guide rail 13, and reciprocates within a measurable area B1, B2 or B3. The guide rail 13 is provided with a scale, a marker, and the like (not shown) for confirming that it is on the straight line L. The measuring device 8 of the present invention
The sensor 11 reciprocating within each of the measurable areas B1, B2, or B3 measures the thickness of a dry coating film (dry coating film) applied to the sheet S or determines the thickness of the dry coating film on the sheet S in advance. The film thickness is measured by the sensor 11 stopped at the measurement position.
When calibrating the sensors 11, the sensors 1 arranged in the adjacent measurable areas B 1 and B 2 and B 2 and B 3
1 and 11 are moved to a corresponding pair of calibration positions C and C, and are simultaneously arranged in a line on the same straight line L, so that the wet coating film of the running sheet S and the uncoated sheet S are removed. Calibration is performed by measuring with these sensors 11.

The calibration is performed by measuring a portion of the running sheet S facing the same straight line L with the sensor 11, and measuring the same portion of the sheet S with the same measurement result. Do it. When the thickness of the coating film is stable in the sheet running direction at the portion of the sheet S facing the calibration position, calibration can be performed so that the measurement results of the sensors 11 and 11 to be calibrated become the same at the same time. In the case where the thickness of the coating film periodically fluctuates along the sheet running direction at the portion of the sheet S facing the calibration position, the thickness of the two sensors 11, 11 to be calibrated corresponds to the distance along the sheet running direction. Calibration can be performed so that the measurement results obtained by phase correction become the same.

The calibration can be performed automatically by the automatic calibration device 16 or manually. The automatic calibration device 16
As shown in FIG. 3, a calibration circuit 18 for automatically calibrating based on the measurement results obtained by the sensors 11 arranged at the calibration position C is incorporated in a measurement circuit 17 connected to each sensor 11 and outputting a measurement result. It is. The measuring circuit 17, measuring coating relationship between the thickness X and the measurement results Y Y = F (X) is incorporated in a zero thickness X of the coating film thickness X ₁ and film at the time of calibration from the sensors 11 _{When 0} is input, Y ₁ = F (X
₁ ) and Y ₀ = F (X ₀ ). The calibration circuit 18 compares the output results Y ₁ and Y ₀ of each measurement circuit 17 with a comparison circuit 18a, and
Of the measuring circuits 17 before the calibration, so that Y ₁ and Y ₀ are the same.
(X)... The circuit is configured so as to automatically calibrate and rewrite the relational expression of each measurement circuit 17.

The measuring device 6 of the present invention is replaced with the measuring device 8 of the present invention, and the coating film in the dry state after the drying step is measured by the measuring device 6 of the present invention. The coating thickness in a later wet state may be measured.
The measurement results obtained by the measuring device 6 of the present invention and / or the measuring device 8 of the present invention are fed back to a coating film thickness adjusting device (for example, a coating gap controller) provided in the coating device 5, and the sheet S May be adjusted so as to have a uniform film thickness in the entire region in the width direction. In particular, the measurement results obtained by the measuring device 8 of the present invention for dry coating films are fed back to the coating device 5 to cope with fluctuations in the thickness of the dry coating film due to fluctuations in the coating liquid composition during drying. can do.

The measuring devices 6 and 8 of the present invention are not limited to those for measuring the thickness of the coating film, but may be those for measuring the thickness of the sheet S after film formation.

[0017]

According to the first aspect of the present invention, since the plurality of thickness measuring sensors can be calibrated easily and quickly, the thickness measuring sensors can be provided at a plurality of measuring positions along the transverse direction of the sheet conveying path. It can be arranged, and the area that is not measured can be made smaller than before to improve the measurement capability. According to the second aspect of the present invention, since the plurality of measurement sensors fixed along the transverse direction of the sheet conveying path can be easily and quickly calibrated at the calibration position, the plurality of measurement sensors fixed along the transverse direction can be calibrated. The thickness in the transverse direction can be simultaneously and accurately measured by the sensor, and the measurement capability can be improved.

According to the third aspect of the present invention, since a plurality of thickness measuring sensors reciprocating in the width direction of the sheet conveying path can be calibrated easily and quickly, the measuring apparatus can be arranged along the width direction crossing the sheet conveying path. A plurality of measurable areas are defined, and a sensor can be arranged in each measurable area so as to reciprocate within the measurable area, thereby improving the measuring capability. According to the measuring device of the present invention, since the measurement results of the plurality of sensors measured at the calibration position are automatically calibrated by the calibration circuit, it is possible to maintain the high-accuracy measurement capability without any trouble.

[Brief description of the drawings]

FIG. 1 is a right side view showing an embodiment of a measuring device of the present invention, and is a right side view schematically showing the entirety of a coating facility provided with the measuring device of the present invention.

FIG. 2 is a plan view showing an arrangement of each sensor of the measuring device of the present invention.

FIG. 3 is a block diagram showing the contents of the measuring device of the present invention.

[Explanation of symbols]

A: Seat running direction, B: Measurement position, B1, B2, B3
... Measureable area, C ... Calibration position, L ... Line, R ... Sheet conveyance path, 11 ... Sensor

Claims (4)

[Claims] A plurality of measurement positions are provided along a transverse direction of a sheet conveying path, and a plurality of calibration positions are provided on the same straight line along a sheet traveling direction of the sheet conveying path, and a plurality of calibration positions are provided between the measurement position and the calibration position. Arrange the thickness measurement sensor so that it can move,
A thickness measuring apparatus for a sheet, wherein a plurality of thickness measuring sensors can be simultaneously arranged at a calibration position. 2. The sheet thickness measuring apparatus according to claim 1, wherein the measurement position is a fixed position. 3. The thickness measuring sensor is arranged so as to be able to reciprocate with a moving tool along a transverse direction of the sheet conveying path from the measurement position to the calibration position.
Or the sheet thickness measuring device according to 2. 4. A measurement circuit connected to the thickness measurement sensor and outputting a measurement result, the measurement result of each sensor is automatically set based on the measurement results measured by the plurality of sensors arranged at the calibration position. 4. The sheet thickness measuring device according to claim 1, further comprising a calibration circuit for calibrating the sheet thickness.