JPH06317419A - Instrument for measuring thickness of sheet - Google Patents

Abstract

PURPOSE:To provide an instrument for measuring the thicknesses of sheets without scratching the sheets so that sheets having uniform thicknesses over the full width can be manufactured. CONSTITUTION:A spherical measuring sensor 14 for operation starting time and roller-like measuring sensor 15 for steady operation which can be rolled in the running direction of a sheet (a) are fitted to the front end of a measuring head 10 so that the sensors can be switched to another. A scan control program for operation starting time which is prepared to measure the thickness of the sheet (a) with the sensor 14 by keeping the sensor 14 in contact with the sheet (a) by continuously moving the head 10 in the width direction while the head 14 is brought into contact with the sheet (a) and another scan control program for steady operation which is prepared to measure the thickness of the sheet (a) with the sensor 15 at regular intervals in the width direction by moving the head 10 at fixed pitches in the width direction of the sheet (a) are provided in a controller 20 so that the programs can be automatically switched to another.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a contact-type measuring device for sheet thickness, and more specifically, a contact-type measuring device for measuring the thickness of a synthetic resin sheet, sheet-like material or film The present invention relates to improvement of a thickness measuring device.

[0002]

2. Description of the Related Art Generally, a synthetic resin sheet is manufactured by heating a synthetic resin pellet put in a hopper with a heater while the synthetic resin pellet is being fed by a screw feeder and melting it, and then the synthetic resin pellet is put on an air knife or a forming roll through a slit of a T die. After being delivered as an uncured sheet, the thickness is reduced to a preset final dimension while being gradually cooled and cured by being stretched between a plurality of stretching rollers whose peripheral speed gradually increases from the upstream side to the downstream side. Then, in this state, it is wound on the winding roller in units of a predetermined length. The sheet thickness is measured immediately before being wound on the winding roller, compared with a set dimension, and if it exceeds an allowable range, the lip opening of the T die, the winding speed, or both are adjusted.

A conventional contact-type measuring device for a sheet thickness is, for example, as shown in FIG. 4, a measuring head (2) mounted on a measuring reference shaft (1) fixedly arranged orthogonal to the traveling direction of the sheet (a). ) Is installed by the ball screw (3) along the guide bar (4) so as to be able to reciprocate, and the thickness of the continuously traveling sheet (a) is measured on the measurement reference shaft (1) by the measurement head (2). ) Is traversed in the width direction of the sheet (a) for measurement.

[0004]

In the above conventional apparatus, the traverse direction of the measuring head (2) is orthogonal to the traveling direction of the seat (a), and the tracing stylus (5) of the measuring head (2) is used. ) Was scanned while crossing the running direction of the sheet (a) with the tip of the sheet (a) continuously in contact with the upper surface of the sheet (a). There was a problem in that it remained along the scratches. The cause of the scratches is the slip that occurs between the probe (5) and the sheet (a), and it suffices to prevent this slip, but this cannot be realized. That is, even if the tip of the tracing stylus (5) is in the form of a roller, the traveling direction of the sheet (a) and the traverse direction of the measuring head (2) are orthogonal to each other, so that if the roller rotation direction is set to one side. Slip occurs on the other side. It is also possible to support the sphere by a ball bearing so that it can rotate freely, but in this case, there is inevitably some play between the sphere and the ball bearing, which requires measurement accuracy on the order of microns. For the measuring device, it causes an error, and dust is caught to prevent free rotation, and further, there is a problem that the friction force with the seat (a) is insufficient and the seat does not rotate satisfactorily. The reality is that it does not reach the target.

The present invention has been proposed in view of the above problems of the conventional apparatus, and its object is to measure the thickness of the sheet without causing scratches on the sheet and to measure the entire length in the width direction. The object of the present invention is to provide a sheet thickness measuring device which enables the production of a sheet having a uniform thickness.

[0006]

In order to achieve the above object, the present invention is supported on a fixed frame by a ball screw so as to be movable in the width direction of a seat along a guide bar, and has a spherical tip. The measurement head for the start of operation, and the measurement head for switching the tip of the measurement sensor for steady operation, which uses a roller whose tip can roll in the running direction of the seat, are attached to the tip. An operation start scan control program that continuously moves from one end to the other end to measure the sheet thickness while keeping the operation start measurement sensor in contact with the sheet, and the measurement head from one end to the other in the width direction of the sheet. Until the seat thickness is measured by contacting the measurement sensor for steady operation with the seat while it is stopped. Repeatedly every time the intermittent movement of the measuring head is stopped, the measuring head is pitch-fed in the width direction of the sheet while being separated from the sheet, and after the pitch feeding, the measurement sensor for steady operation is brought into contact with the sheet to measure the sheet thickness. And a controller capable of automatically switching between the scanning control program for steady operation and the scanning control program for steady operation.

Further, according to the present invention, the above-mentioned measuring heads are arranged so as to face both sides of the sheet, and the sheet thickness is measured by the relative difference between the measured values of the both.

[0008]

When the measurement sensor at the tip of the measuring head is switched to the measurement sensor for operation start at the start of operation, the controller program is automatically switched to the scan control program for operation start. In this state, the production of the sheet is started, and the thickness of the produced sheet is measured by the measuring head.
The measurement at the start of operation is performed by an operation start measuring sensor having a spherical tip. Further, this operation start scan control program continuously moves the measuring head from one end to the other end in the width direction of the sheet to measure the sheet thickness while the operation start measurement sensor is in contact with the sheet. Is. As a result, the thickness of the sheet at the start of manufacturing is measured and displayed over the entire length in the width direction of the sheet, and is compared with the set dimension to adjust the lip opening degree and the like. The sheet thickness at the start of operation tends to fluctuate until the entire manufacturing equipment enters the steady operation, and is cut and removed without being used as a product. However, there is no problem.

When the lip opening and the like are adjusted and the thickness of the manufactured sheet stabilizes within the allowable range of set dimensions,
Enter steady operation. That is, if the measurement sensor at the tip of the measurement head is switched to the steady operation measurement sensor, the controller program is automatically switched to the steady operation scan control program. Thus, the thickness of the sheet is measured at constant pitch intervals in the width direction of the sheet.
Since the leading edge of the measurement sensor for steady operation is a roller that can roll in the traveling direction of the sheet, no slip occurs when the sheet comes into contact with the sheet, and the sheet is not scratched.

Since the measuring heads are arranged so as to face each other on both sides of the sheet and the sheet thickness is measured by the relative difference between the two measured values, the waviness in the width direction of the sheet is canceled and the sheet thickness is compensated. Can be measured.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic front view of the whole embodiment of the present invention, FIG. 2 is a vertical sectional side view of a main portion of a measuring head tip portion, and FIG. 3 is a schematic plan view of the measuring head tip portion. At
(10) shows a measuring head and (20) shows a controller. However, in order to facilitate understanding, in FIG. 1, the mounting direction of the tip of the probe is shown rotated by 90 °, but it is understood that the mounting direction in FIG. 2 is normal. I want to.

The measuring head (10) has a fixed frame (11).
On the other hand, a ball screw (12) movably supports along the guide bar (13) in the width direction of the seat (a), and has a spherical tip at the time of starting measurement sensor (14).
And a measurement sensor (15) for steady operation, which is a roller whose tip is rollable in the traveling direction of the sheet (a), is switchably attached to the tip. The measurement sensor for operation start (14) and the measurement sensor for steady operation (15) are used to convert the minute vertical displacement of the contact part at the tip into an electric quantity and measure it in micron order. Molds and other known types can be used. And
Both the operation start measurement sensor (14) and the steady operation measurement sensor (15) are configured to output a measurement signal to the controller (20) during operation.

The measuring head (10) includes an air cylinder (1
7) A lifting body (16) that can be lifted up and down is provided, and a supporting shaft (18) is fixed to the tip of the lifting body (16) by inclining at a predetermined angle, and a holder (19) is attached to the supporting shaft (18). Is rotatably supported, and the operation start measurement sensor (14) and the steady operation measurement sensor (15) are fixed to the holder (19) at a predetermined angle, for example, 90 °. The operation start measurement sensor (14) and the steady operation measurement sensor (15) are rotatable around the support shaft (18) between the measurement position and the retracted position via the holder (19). The holder (19) can be fixed to the measurement position and the retracted position by operating the clamp lever (21). Moreover, when one of the operation start measurement sensor (14) and the steady operation measurement sensor (15) is at the measurement position, the measurement sensor axis at the measurement position is parallel to the vertical direction of the air cylinder (17). So that both measurement sensors (14) (15) have a predetermined inclination angle with respect to the axis of the support shaft (18).
Is attached to.

The controller (20) is a servo motor (2
2) allows the measuring head (1
0) is continuously moved from one end to the other end in the width direction of the sheet (a) to start the operation. At the time of operation start to measure the sheet thickness while the measurement sensor (14) is in contact with the sheet (a). The scanning control program (p1) and the servomotor (22) intermittently move the measuring head (10) through the ball screw (12) from one end to the other end of the seat (a) in the width direction at a constant pitch. The stationary measurement sensor (15) is in contact with the sheet (a) through the air cylinder (17) during the stop to measure the sheet thickness, and after the measurement,
The measurement sensor for steady operation (15) is separated from the seat (a), the measurement head (10) is pitch-fed in the width direction of the seat (a), and after the pitch feed, the measurement sensor for steady operation (1
Automatically switches internally to the scan control program for steady operation (p2), which repeats 5) contacting the sheet (a) and measuring the sheet thickness each time the measuring head (10) stops intermittently. It is possible. Although both programs (p1) and (p2) are not shown in the figure, they are used with reference numerals to prevent confusion.

The measuring heads (10) are installed facing each other on both sides of the sheet (a) and have the same structure. However, the upper and lower ball screws (12) are linked by a timing belt (26) so that they can be operated at the same speed. An elevating guide (23) for the elevating body (16) is installed on a part of the measuring head (10), and the lower end portion of the elevating guide (23) has a lower end position of the elevating body (16) for thick and thin objects. A stopper (24) that can be switched and changed with one touch is slidably installed. If this stopper (24) is pushed to the left side in FIG. 2 and fixed, it will be for thick objects, and if it is pulled out to the right side and fixed, it will be for thin objects. A thickness calibration master (25) is installed on a fixed frame (11) so as to be capable of undulating on the starting end side (origin) of the traverse operation of the measuring head (10). The thickness calibration master (25) is classified into thick ones and thin ones, which are selectively used depending on the thickness of the sheet (a) to be manufactured. Origin),
When starting the traverse, the elevation body (16) of the measuring head (10) is approached from both sides or one side to calibrate the thickness of the sensor. At the time of this thickness calibration, the operation start measurement sensor (14) and the steady operation measurement sensor (15)
Among the measurement signals transmitted from the controller to the controller (20), the controller (20) determines which of the measurement signals has changed in thickness calibration, and the result of this determination is the scan control program for operation start time. (P1) or the scan control program for steady operation (p2) is automatically switched. When the measurement heads (10) are placed on both sides of the sheet (a) facing each other and the measurement sensors on both sides do not match, the controller (20) automatically uses the scan control program for steady operation (p2). The measurement is performed so that the sheet (a) is not damaged. This is because when measuring the thickness, the measurement signal of the operation start measurement sensor (14) changes from one measurement head (10), and the steady operation measurement sensor (15) changes from the other measurement head (10).
It is judged by the change of the measurement signal of.

An embodiment of the present invention has the above-mentioned configuration,
Next, the measurement operation will be described. At the start of operation, the measuring head (1
If the measurement sensor at the tip of the elevator (0) is switched to the measurement sensor for operation start (14), the program of the controller (20) will be automatically changed to the scan control program for operation start (p1) during thickness calibration at the start of measurement. Can be switched. And
The sheet (a) produced by starting the production of the sheet (a)
The thickness of is measured with a measuring head (10). The measurement at the start of operation is performed by the operation start measurement sensor (14) having a spherical tip. In addition, the scan control program for starting operation (p1) uses the measurement head (10) for the seat (a).
Is continuously moved from one end to the other end in the width direction to measure the sheet thickness while the operation start measurement sensor (14) is in contact with the sheet (a). This allows
The thickness of the sheet (a) at the start of production is the sheet (a)
Is measured and displayed over the entire length in the width direction, and is compared with the set dimension to adjust the lip opening degree and the like.

When the lip opening and the like are adjusted and the thickness of the manufactured sheet (a) stabilizes within the allowable range of the set dimension, the steady operation is started. That is, if the measurement sensor at the tip of the lifting body of the measurement head (10) is switched to the steady operation measurement sensor (15), the controller (20) program is automatically switched to the steady operation scan control program (p2). To be Thus, the thickness of the sheet (a) is measured at constant pitch intervals in the width direction of the sheet (a).
Since the measurement sensor (15) for steady operation has a roller that can roll in the traveling direction of the sheet (a), no slip occurs when the sheet (a) is contacted, and the sheet ( There is no scratch on a).

Since the measuring head (10) is arranged on both sides of the sheet (a) so as to face each other and the sheet thickness is measured by the relative difference between the two measured values, the waviness in the width direction of the sheet (a) is offset. Then, the thickness of the sheet (a) can be measured. The measuring head (10) returns to the starting end side (origin) of the traverse operation, and when the traverse is started immediately or after a lapse of a predetermined time, the lifting body (16) of the measuring head (10) is approached from both sides. Thickness calibration master (2
According to 5), the thickness is calibrated before the measurement of the sheet (a). After the thickness is calibrated, the measuring head (10) is moved at high speed in a state of being separated from the sheet (a) until it reaches one end of the sheet (a), and a sheet end detection sensor ( (Not shown)
To detect one end (measurement start end) of the sheet (a) and reduce the feed speed of the measurement head (10) to a continuous contact scanning speed, or to stop the feed of the measurement head (10) and At the same time, the air cylinder (17) causes the lifting body (16) to approach the seat (a) to execute the operation start scan control program (p1), or execute the steady operation scan control program (p2). . Then, when the measurement head (10) reaches the other end (measurement end) of the seat (a), the lifting end (16) is separated from the seat (a) via the air cylinder (17) by the seat end detection sensor. Then, the measuring head (10) is returned to the origin at high speed.

In the above embodiment, the measurement heads (10) are arranged opposite to each other on both sides of the sheet (a), but in the present invention, the lower surface of the sheet (a) is supported by the measurement reference shaft. Aside from the top of the sheet (a), the measuring head (10)
You may make it contact. Further, the automatic switching means between the scan control program for start of operation (p1) and the scan control program for steady operation (p2) is not limited to the above-mentioned embodiment, and may be another method.

[0020]

EFFECTS OF THE INVENTION According to the present invention, at the start of operation when the thickness of the sheet tends to fluctuate, even if the sheet is scratched, this portion is not used as a product and is cut and removed, so that there is no problem. However, when entering the steady operation, the measurement sensor at the tip of the measuring head can be switched between the operation start measurement sensor and the steady operation measurement sensor so that the seat is not scratched, and the controller The program can be switched between the scan control program for operation start and the scan control program for steady operation, and the intended purpose can be achieved with a simple configuration.

Further, according to the present invention, the measuring heads are arranged so as to face each other on both sides of the sheet, and the sheet thickness is measured by the relative difference between the two measured values. Therefore, the waviness in the width direction of the sheet is canceled. Then, the thickness of the sheet can be measured.

[Brief description of drawings]

FIG. 1 is an overall schematic front view according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional side view of a main portion of a measurement head tip portion.

FIG. 3 is a schematic plan view of the tip of the measuring head.

FIG. 4 is a schematic front view of a conventional device.

[Explanation of symbols] a Seat 10 Measuring head 11 Fixed frame 12 Ball screw 13 Guide bar 14 Measurement sensor for starting operation 15 Measurement sensor for steady operation 16 Lifting body 17 Air cylinder 18 Support shaft 19 Holder 20 Controller 21 Clamp lever 22 Servo motor 23 Lift guide 24 Stopper 25 Thickness calibration master p1 Scan control program for operation start p2 Scan control program for steady operation

Claims (2)

[Claims] 1. A measurement sensor for starting operation, which is movably supported by a ball screw in a seat width direction along a guide bar with respect to a fixed frame and has a spherical tip, and a traveling direction of the sheet. A measuring head with a rollable roller and a measuring sensor for steady operation that can be switched at the tip, and a measuring head for continuous operation from one end to the other end in the width direction of the seat when starting operation A scan control program for operation start that measures the sheet thickness while keeping the measurement sensor in contact with the sheet, and the measurement head moves intermittently from one end to the other end in the width direction of the sheet at a constant pitch to make steady during the stop. The measurement sensor for operation is brought into contact with the sheet to measure the sheet thickness, and after measurement, the measurement sensor for steady operation is separated from the sheet and the measurement head is moved in the width direction of the sheet. Automatically feeds the scan control program for steady operation, in which the measurement sensor for steady operation is brought into contact with the sheet and the sheet thickness is measured after each intermittent movement of the measuring head. A sheet thickness measuring device comprising a controller capable of switching operation. 2. The measuring head according to claim 1 is arranged on both sides of a sheet so as to face each other, and the sheet thickness is measured by the relative difference between the measured values of the both. The sheet thickness measuring device described.