JPH04188011A - Film thickness measurement device - Google Patents

Abstract

PURPOSE:To precisely measure the thickness of a sheet to be measured by providing a support device for supporting a rotary shaft with the use of force in accordance with the tension of the sheet to be measured in the neighborhood of a part on which the sheet to be measured of the rotary shaft is running. CONSTITUTION:Since a variety of tension is applied on a sheet 5 to be measured in accordance with thickness and the other conditions when measurement is performed, bending stress is applied on a rotary shaft 1 and causes deflection in the contact face and the rear side of the sheet 5 to be measured, but since a roller 20 is set in the direction for resisting the bending stress of the sheet 5 to be measured and the bend stress applied on the rotary shaft 1 is set off by the force in accordance with the tension of the sheet 5 to be measured with the use of an air cylinder 21 to support, the production of distortion is prevented to enable precise measurement. It is also good to replace the air cylinder 21 with a spring and one roller 20 is arranged axially, however a plurality of the rollers 20 may as well be provided to produce the same effect in the case where the width of the sheet 5 to be measure is wide.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to, for example, a magnetic tape manufacturing line.
The present invention relates to a film thickness measuring device that measures the thickness of an applied coating film.

[Conventional technology]

FIGS. 2 and 3 are a block diagram and a perspective view, respectively, showing the overall structure of a conventional film thickness measuring device disclosed in, for example, Japanese Patent Laid-Open No. 1-27400. (1) is a rotating shaft rotatably supported by a frame (2), B) is a rotary drive motor that rotationally drives this rotating shaft (1), and (A) is a rotating shaft at a predetermined distance from the surface of the rotating shaft (1). A light-shielding plate is opened and arranged parallel to the axial direction, 4 is a sheet to be measured that runs on the surface of the rotating shaft (1), (6) is a laser beam generator that generates a laser beam (6a), and bacteria are reflected. At the mirror, the laser light generator (
The laser beam (6a) from 6) is condensed by a condensing lens (81) and controlled to scan between the rotation axis (1) and the surface of the sheet to be measured (9 and the light shielding plate (a). .

(9) is a light receiver that receives the laser beam (6a) scanned as described above through a condensing lens aO1, and (11) is a detection head that incorporates these (6) to 00), with a light shield at the bottom. The upper part is a suspension mechanism (12) that holds the plate (a)
It is suspended by. (13) is connected to the detection head (11) via the suspension mechanism (12) by the drive of the motor (14).
A head moving mechanism (15) moves the sheet to be measured so as to scan it on the rotating shaft (1). [(13) is a control unit that scans the detection head (11) at a predetermined speed on the rotating shaft (1) by controlling the moving speed; The counter to count (17) is this counter (16
The calculator (18) that calculates the film thickness of the sheet to be measured (9) based on the pulse count number of ) is a display that displays the film thickness calculated by this calculator (17).
~(18) constitute a film thickness detection means (19).

Next, the operation of the conventional film thickness measuring device configured as described above will be explained.

First, a laser beam (
6a) is the point in time when the light is incident on the reflection mirror (7) and reflected by the condensing lens (FF"ct), and passes between the rotation axis (1) and the measured sheet (51 and the light shielding plate). The beam diameter becomes the minimum at , and the laser beam (6a) is scanned at a constant speed in the direction perpendicular to the rotation axis (1), that is, in the direction of the gap.After scanning, the laser beam (6a) is focused again by the condenser lens α■ and is received. At this time, the laser beam (6a) enters the receiver (9) only while passing through the gap, so the receiver (9) generates a pulse waveform with a width proportional to the cap. By outputting a signal and counting the pulses with a counter (16), a count number corresponding to the pulse width can be obtained.

On the other hand, the control unit (15) detects the speed of the sheet to be measured (5) by measuring the rotational speed of the rotary drive motor (3), and controls the head moving mechanism (I3) by driving the motor 44). Scanning the detection head (11) at a predetermined speed corresponding to the speed of the sheet to be measured (5),
Rotating shaft (1) and sheet to be measured (5) (between l and light shielding plate)
The gap between is measured. In addition, since a step (1) is provided in advance on the rotating shaft (1) to serve as a reference for thickness calculation, the difference in counts at this step is measured and stored in advance. The gap between the rotating shaft (1) and the light shielding plate 4) and the sheet to be measured (51 and the light shielding plate 4)
A calculation unit (17) calculates the difference in count between the gap and the thickness, and the thickness is calculated and displayed on a display (18).

[Invention or problem to be solved]

Since the conventional film thickness measuring device is configured as described above, when measuring the film thickness of the sheet to be measured +51, the tension applied to the sheet to be measured (51 causes distortion in the rotation axis (1), There was a problem in that the measured and memorized gap between the rotating shaft [1] and the light shielding plate (2) changed, causing an error in the film thickness measurement value, resulting in inaccurate measurement results.

This invention was made to solve the above-mentioned problems, and it is an object of the present invention to provide a film thickness measuring device that can accurately measure the thickness of a sheet to be measured.

[Means to solve the problem]

The film thickness measuring device according to the present invention rotates at a predetermined speed and the sheet to be measured runs on the surface of the rotating shaft.The rotating shaft rotates at a predetermined speed and the sheet to be measured runs on the surface of the shaft. A support device is provided to support the device.

[Effect]

The support device of the film thickness measuring device in this invention detects the tension applied to the sheet to be measured and supports the rotating shaft with a force corresponding to this tension, so that the support device rotates due to the tension applied to the sheet to be measured. Prevents distortion from occurring in the shaft.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
Figure 0 is a perspective view showing the configuration of a film N measuring device in an embodiment of the present invention. 5I is the same as that of the conventional apparatus shown in FIGS. 2 and 3, and the film thickness detecting means (19) shown in FIG. 2, although not shown, is naturally included in this embodiment. Therefore, the following explanation will also be made using FIG. 2.

(20) is a roller provided below and parallel to the rotating shaft (1), (21) rotatably supports this roller (2o), and the sheet to be measured (5) is detected by a tension sensor (not shown). ) with a force corresponding to the tension of
) is an air cylinder that supports the rotating shaft ( ) from below, and these rollers (2o) and the air cylinder (21) constitute a support device (22).

In the film thickness measuring device according to an embodiment of the present invention configured as described in 1., first, the laser beam (6a) emitted from the laser beam generator (6) is
After being incident on the reflection mirror (to) and being reflected, the beam is focused by the condenser lens 8, and the beam diameter reaches its minimum when it passes between the rotation axis (1) and the target sheet) f5] and the light shielding plate 4). The beam is scanned at a constant speed in the direction perpendicular to the rotation axis (1), in the direction of the twisting gap. After scanning, the laser beam (6a) is again focused by the condenser lens 00) and received by the light receiver (9). At this time, the laser beam (6a) is incident on the light receiver (9) only while passing through the gap, so the light receiver (9) outputs a pulse waveform signal with a width proportional to the cap, and this is sent to the counter. By counting pulses in (16), a count number corresponding to the pulse width can be obtained.

On the other hand, the control unit (15) detects the speed of the sheet to be measured (5) by measuring the number of rotations of the rotary drive motor (3), and controls the head movement mechanism (13) by driving the motor (2). By scanning the detection head (11) at a predetermined speed corresponding to the speed of the sheet to be measured (51), the gap between the rotating shaft (1) and the sheet to be measured (the phrase and the light shielding plate (4) is measured. .Also, since a step (1) is provided in advance on the rotating shaft (1) to use as a reference for thickness calculation, the difference in counts at this step is measured and stored in advance. Rotating shaft (1) and light shielding plate (71)
The thickness is calculated by calculating the difference in the number of counts between the gap between the sheet to be measured (51) and the gap between the sheet to be measured (51 and the light-shielding plate (2)), and is displayed on the display (18).

Also, during measurement, various tensions are applied to the sheet to be measured (9) depending on the thickness and other conditions, so bending stress is applied to the rotating shaft (1), causing it to bend on the side opposite to the contact surface with the sheet to be measured (5). However, the roller (20) is arranged in a direction that resists the bending stress of the sheet to be measured H, and the rotation axis (1 ) is supported so as to cancel out the bending stress acting on it, preventing the occurrence of distortion and making accurate measurements possible.

In the above embodiment, the rotary shaft (1) is supported by the air cylinder (21) via the roller (20) with a force corresponding to the tension of the sheet to be measured (5), or the air cylinder (21) is Alternatively, it may be supported by a spring, or a roller (
Although one sheet 20) is provided in the axial direction, if the width of the sheet to be measured (51) is wide, a plurality of sheets may be provided and the same effect will be obtained.

Furthermore, in the above embodiment, with one laser beam (6a),
The rotating shaft (1) and the surface of the sheet to be measured F51 are being scanned. Two laser beams (6a) are used to scan one surface of the rotating shaft (1) and the other of the surface of the sheet to be measured (5). It goes without saying that similar effects can be obtained even when applied to a fixed film thickness measurement in which each surface is scanned.

〔Effect of the invention〕

As described above, according to the present invention, a support device for supporting the rotating shaft with a force corresponding to the tension of the measuring sheet is provided near the part of the rotating shaft where the sheet to be measured travels, and then the sheet to be measured is It becomes possible to provide a film thickness measuring device that can accurately measure the thickness of ~.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the configuration of a film thickness measuring device according to an embodiment of the present invention, and FIGS. 2 and 3 are a front view and a perspective view showing the internal structure of a conventional film thickness measuring device, respectively. . In the figure, (1) is the rotating shaft 5, (a) is the light shielding plate, ((
6) is a sheet to be measured, (6a) is a laser beam, (1) is a film thickness detection means, and (22) is a support device. Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent Patent Attorney Masuo Oiwa Figure 1 1: Co-rotating shaft 4, light shielding 9, ; 'j-

Claims (1)

[Claims] a rotating shaft that rotates at a predetermined speed and on which a sheet to be measured travels; a light-shielding plate disposed parallel to the axial direction at a predetermined distance from the surface of the rotating shaft; and the rotating shaft and the measured object. a film thickness detection means for detecting the film thickness of the sheet to be measured by scanning between the surface of the sheet and the light shielding plate with a laser beam and measuring the transmission time of the laser beam; and the sheet to be measured on the rotating shaft. 1. A film thickness measuring device comprising: a support device that is provided near a portion where the rotating shaft runs and supports the rotating shaft with a force corresponding to the tension of the sheet to be measured.