JPH07182724A - Method and device for measuring tape - Google Patents

Abstract

PURPOSE:To provide a method and a device for measuring tape capable of simultaneously measuring tape width fluctuations causing fluctuations in the width direction of a travelling tape, wavings and vertical fluctuations in a completely separated form in a magnetic tape device. CONSTITUTION:One end of a tape 1 is the upper end and another end is the lower end. The light projecting and receiving sections 2-1 and 2-2 of a first measuring equipment measure the displacement in the width direction of the upper end of the tape. The light projecting and receiving sections 4-1 and 4-2 of a second measuring equipment measure the displacement in the width direction of the lower end of the tape. Positions in which the first and second measuring equipments 2 and 4 perform measuring are set so that positions in the longitudinal direction of the tape are almost the same. The light projecting and receiving sections 6-1 and 6-2 of a third measuring equipment measure the diplacement in a width direction on the upper end of the tape. Positions in which the first and third measuring equipments perform the measurement are set in the position different from each other in the longitudinal direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a tape recorder, a VT.
In a magnetic recording / reproducing apparatus such as R, the present invention relates to an apparatus for measuring a fluctuation in a tape width direction during running of a tape used as a recording medium.

[0002]

2. Description of the Related Art In recent years, the amount of information handled by video and information equipment has become larger and larger, and the capacity of devices for recording and reproducing the data is rapidly increasing. In magnetic recording devices, recording media have been made longer and higher in density. Particularly in a magnetic tape device, it is necessary to reduce the thickness of the tape in order to enable long-time recording, and more stable tape running is required from the viewpoint of high density.

Therefore, in the magnetic tape device, the fluctuation in the width direction of the tape during running is measured without disturbing the running,
It became necessary to evaluate accurately. One of the tape width displacement measuring devices for measuring the variation in the width direction is a non-contact displacement measuring device using a laser beam (for example, "Factors of frictional wear of tape-head running system and countermeasures for troubles" Engineering Information Center. Publishing Department P163-166). An example of these measuring instruments will be described.

FIG. 15 shows the operating principle of a conventional laser contour measuring instrument. In FIG. 15, 1 is a tape, 2
2 is a semiconductor laser projecting unit, 23 is a polygon mirror, 24
Is a reflection mirror, 25 is a collimator lens, 26 is a light receiving lens, 27 is a light receiving element, and 28 is an edge detection device.

The operation of the laser contour measuring instrument constructed as described above will be described below. The laser beam emitted from the semiconductor laser projecting unit 22 becomes a beam which is scanned by the polygon mirror 23 at a constant cycle. This light beam is reflected by the reflection mirror 24 and then made into a light beam which is scanned in parallel by the collimator lens 25. This light beam is projected onto the tape 1, which is the object to be measured. The laser beam that scans the tape 1 is collected by the light receiving lens 26, applied to the light receiving element 27, and converted into an electric signal according to the brightness of the light. By inputting this signal to the edge detection device 28, the length of time during which light and dark are generated is calculated, and the width of the tape 1 is calculated. In this way, the width error of the tape 1 can be measured by comparing the calculated width of the tape 1 with the reference value.

[0006]

However, it is not only the influence of the tape width error that causes a problem in the tape width direction variation. There are three possible factors to consider.

The first point is the variation in width within one tape, which is called tape width variation. The tape width variation means a deviation from the standard tape width. The second point is the deviation when the tape width is a reference value but the tape is deformed in a wave shape, and this is called waving. Tape width variation and waving are physical properties of the tape itself and are related to tape width error. The third point is due to the running of the tape, and is the fluctuation caused by the running of the tape itself while swinging up and down. This is called tape vertical fluctuation. These three variations are combined and observed as variations in the tape width direction during running. Therefore, in order to completely grasp the variation in the tape width direction, the tape measuring device needs to measure the above three variations separately.

In the configuration of the laser contour measuring device shown in FIG. 15, the tape width corresponds to the dark portion of the light receiving portion. Therefore,
The tape width can be measured by measuring the time taken for the laser beam to scan the dark area with an edge detection device. However, regarding the waving and the vertical fluctuation of the tape, both of them have a problem that they cannot be distinguished from each other, because it is observed that the tape ends move in the same direction by the same distance.

In view of the above problems, it is an object of the present invention to provide an apparatus for completely separating and measuring the width fluctuation, waving, and vertical fluctuation of a running tape.

[0010]

According to a first aspect of the present invention, there is provided a process of setting a widthwise displacement at time t at a measurement position A at one end of the tape as α (t) in a tape traveling at a speed v. , A process in which the widthwise displacement at the time t at the position where the longitudinal direction is almost the same on the other end of the measurement position A is β (t), and the tape is moved longitudinally on the same end as the measurement position A. The process of setting the widthwise displacement at time t at a position separated by a distance e in the reverse direction of travel as γ (t), and the tape width fluctuation, waving, and tape vertical fluctuation at time t at the measurement position A are tape width fluctuation p (t) = α (t) −β (t), waving q (t) = {β (t) −α (t)} / 2 + γ (t
-E / v), tape vertical fluctuation r (t) = [alpha] (t)-[gamma] (t-e / v).

Further, in the invention of claim 2 of the present application, in the tape traveling at the speed v, the process of setting the widthwise displacement at the time t at the measurement position A at one end of the tape to α (t), and the measurement position A The process of setting β (t) as the widthwise displacement at time t at the position where the longitudinal direction is substantially the same on the other end of the tape, and the distance in the tape traveling direction in the longitudinal direction on the same end as the measurement position A The process of setting the widthwise displacement at time t at a position separated by e as γ (t), and the tape width fluctuation, waving, and tape vertical fluctuation at time t at the measurement position A: tape width fluctuation p (t) = α (t) -β (t), waving q (t) = {α (t) + β (t)} / 2-γ
(t) + α (t-e / v), tape vertical fluctuation r (t) = γ (t) -α (t-e / v)

Further, in the invention of claim 3 of the present application, the measuring device a which detects and outputs the widthwise displacement of one end of the tape and the position of the tape measured by the measuring device a and the position in the longitudinal direction are substantially the same. A measuring instrument b for detecting and outputting the widthwise displacement of the other end, and a measuring instrument for detecting and outputting the widthwise displacement of the tape end at a position different in longitudinal direction from the measuring instruments a and b. c, a storage device that holds at least one of the values output by the measuring instruments a, b, c, and the measuring instruments a, b, c
And an arithmetic unit for calculating at least one of tape width variation, waving, and tape up-and-down variation using the value output by the storage device and the value held by the storage device.

According to the invention of claim 4 of the present application, measuring devices a, b,
c is a non-contact optical measuring device.

According to the invention of claim 5 of the present application, measuring devices a, b,
c is characterized in that a reflecting mirror is arranged on the optical path used for measurement.

The invention according to claim 6 of the present application is characterized in that at least one of the measuring device a and the measuring device b is a measuring device movable in the width direction of the tape.

The invention of claim 7 of the present application is characterized in that at least one of the measuring device a and the measuring device c is a measuring device movable in the longitudinal direction of the tape.

According to the invention of claim 8 of the present application, measuring devices a, b,
c is provided with one or more tape guides for regulating the position of the tape near the position for measuring the tape.

[0018]

According to the first aspect of the present invention, in the tape running at the speed v, the widthwise displacement α (t) at the time t at the measuring position A at one end of the tape and the other of the measuring position A The widthwise displacement β (t) at time t at the position where the longitudinal direction is almost the same on the end, and the position e at the same end as the measurement position A at a distance e in the longitudinal direction of the tape and in the reverse direction of the tape. The widthwise displacement γ (t) at time t is measured. The difference between α (t) and γ (t-e / v), which is the displacement in the width direction of the same measured point on the tape, is the displacement in the width direction of the same measured point at different times, so the tape vertical fluctuation r (t ) Can be calculated. Further, since the difference between α (t) and β (t) is the difference in the widthwise displacement between both ends of the tape at the same position in the longitudinal direction, the tape width variation p (t) can be calculated. further,
At the same time, it is possible to calculate the fluctuation that is a combination of the waving and the tape vertical fluctuation, so that the waving q (t) can be separated and calculated by subtracting the previously calculated value of the tape vertical fluctuation. Therefore, it is possible to obtain the tape width variation, the waving, and the tape vertical variation at a certain time.

According to the second aspect of the present invention, in the tape traveling at the speed v, the widthwise displacement α (t) at the time t at the measurement position A at one end of the tape and the other of the measurement positions A The widthwise displacement β (t) at the time t at the position where the longitudinal direction is almost the same on the end of the, and the position e at the same end as the measurement position A and the distance e in the longitudinal direction of the tape in the traveling direction of the tape. Time t
The widthwise displacement γ (t) of is measured. The tape vertical fluctuation r (t) is calculated from the difference between α (t−e / v) and γ (t), which are the displacements in the width direction of the same measured point on the tape. The tape width variation p (t) is calculated from the difference between α (t) and β (t). At the same time, since it is possible to calculate the fluctuation that is a combination of the waving and the tape vertical fluctuation, the waving q (t) is separated and calculated by subtracting the previously calculated value of the tape vertical fluctuation. Therefore, it is possible to obtain the tape width variation, the waving, and the tape vertical variation at a certain time.

Further, according to the invention of claim 3 of the present application, the first measuring device for detecting and outputting the widthwise displacement of one end in the tape width direction, the tape position measured by the first measuring device and the tape longitudinal direction. The second measuring device that detects the displacement in the widthwise direction of the other end of the tape and outputs the same in the longitudinal direction of the tape is different from the tape positions measured by the first measuring device and the second measuring device. The tape width direction displacement is measured by three measuring devices, which are the third measuring device that detects and outputs the width direction displacement of the tape end portion at the position, and inputs the value to the arithmetic unit. Further, by holding the value of the widthwise displacement in the storage device, the values of the widthwise displacement at different times are input to the arithmetic device. The tape vertical fluctuation is calculated from the difference in the widthwise displacement of the same measured point on the tape measured by the first measuring instrument and the third measuring instrument. The tape width variation is calculated from the difference in the widthwise displacement between the first measuring device and the second measuring device. At the same time, it is possible to calculate the fluctuation that is a combination of the waving and the tape vertical fluctuation. Therefore, the waving is separated and calculated by subtracting the value of the tape vertical fluctuation obtained previously. Therefore, calculation is performed by the arithmetic device using the values of the widthwise displacement of the same measured point at different times, and the tape width fluctuation at a certain time,
It is possible to obtain waving and tape vertical fluctuations.

Further, according to the inventions of claims 4 and 5, the measuring device is an optical type and the reflecting mirror is arranged on the optical path. Therefore, the optical path of the measuring device optical system can be freely changed. Can be done. Therefore, it is possible to greatly expand the degree of freedom in arranging the measuring device for the displacement in the width direction. As a result, since the measuring device is large, it is possible to perform the measurement even in a magnetic tape device in which the measuring device cannot be arranged around the tape.

According to the invention of claim 6 of the present application,
By providing means for moving at least one of the measuring instrument and the second measuring instrument in the tape width direction, it is possible to change the distance in the tape width direction at the measurement position. This makes it possible to measure the variation in the width direction corresponding to various tapes having different tape widths.

According to the invention of claim 7 of the present application,
By providing means for moving at least one of the measuring instrument, the second measuring instrument, and the third measuring instrument in the tape longitudinal direction, the distance in the tape longitudinal direction at the measurement position can be changed. As a result, it is possible to eliminate the case where accurate measurement cannot be performed due to the cycle of vertical fluctuation of the running tape. Therefore, it is possible to measure the fluctuation in the tape width direction corresponding to the vertical fluctuations in every cycle.

According to the invention of claim 8 of the present application,
By providing at least one tape guide that regulates the position of the tape near the position where the tape measuring device, the second measuring device, and the third measuring device measure the tape, the upper and lower ends of the tape are moved by the tape guide. Since it is regulated, vertical movement due to running of the tape between the tape guides is suppressed. Also,
It is also possible to obtain stable tape running.

[0025]

Embodiments of the tape measuring apparatus and the tape measuring method of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the structure of a tape measuring apparatus according to the first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a tape, which is run on a fixed path at a constant speed by a tape running system (not shown). One end of the tape 1 is the upper end and the other end is the lower end. Reference numeral 2-1 is a first measuring device light projecting portion, and 2-2 is a first measuring device light receiving portion. The light projecting portion and the light receiving portion are paired to measure the widthwise displacement of the upper end of the tape. Four
Reference numeral -1 is a second measuring device light projecting portion, and 4-2 is a second measuring device light receiving portion. The light projecting portion and the light receiving portion are paired to measure the widthwise displacement of the lower end of the tape. The position where the first measuring device performs measurement and the position where the second measuring device performs measurement are set to be substantially the same in the longitudinal position of the tape. Reference numeral 6-1 is a third measuring device light projecting portion, and 6-2 is a third measuring device light receiving portion. The light projecting portion and the light receiving portion form a pair, and the displacement in the width direction is measured at the upper end of the tape. The position where the first measuring device 2 performs the measurement and the position where the third measuring device 4 performs the measurement are set to different positions in the longitudinal direction. 8
Is a storage device and can hold the output value of the third measuring device 6 for a certain period of time. Reference numeral 9 denotes an arithmetic device, which performs an arithmetic operation using the output values of the first measuring device 2 and the second measuring device 4 and the values held in the storage device 8 to calculate tape width fluctuation, waving, and tape vertical fluctuation. To do.

The operation of the tape measuring device configured as described above will be described. First, the operating principle of the first measuring device 2 will be described with reference to FIG. The laser beam 10 emitted from the semiconductor laser 11 in the light projecting section 2-1 is
The light is emitted from the light projecting optical system 12 as parallel light. The laser beam 10 is projected from the light projecting unit 2 toward the light receiving unit 2-1. Then, the laser beam 10 is focused on the light receiving element 14 by the light receiving section optical system 13 in the light receiving section 2-2. When the tape 1 enters as a shield in the range where the parallel laser beam 10 passes, a shadow is formed and the amount of light incident on the light receiving element 14 changes. This change in the amount of light is output by the light receiving element 14 as a change in voltage. First with such a configuration
FIG. 3 shows the relationship between the output voltage of the measuring instrument and the light-shielding area. The light shielding area has a one-to-one relationship with the displacement amount of the tape end. Therefore, the widthwise displacement, which is the relative position of the end portion of the tape 1, can be obtained from the output voltage value of the first measuring device 2.

The second measuring device 4 and the third measuring device 6 can also perform the same operation as described above to obtain the widthwise displacement of the end portion of the tape 1.

The positional relationship in which the first measuring device 2, the second measuring device 4, and the third measuring device 6 measure the displacement in the tape width direction will be described. FIG. 4 shows the measurement position on the tape 1. The first measuring device 2 measures the widthwise displacement at the measurement position A at the upper end of the tape. The second measuring device 4 measures the displacement in the width direction at the measuring position B at the lower end of the tape. The measurement position A and the measurement position B are set so that the positions in the longitudinal direction on the tape are substantially the same. The third measuring device 6 measures the widthwise displacement at the measuring position C at the upper end of the tape. The measurement position C is set so as to be separated from the measurement position A by a distance e in the longitudinal direction of the tape in the reverse direction of tape travel. Therefore, the measurement results of the widthwise displacement at the measurement position A, the measurement position B, and the measurement position C are the first measurement device 2, the second measurement device 4, and the third measurement device 6.
Can be obtained as the output of each.

Next, the outputs of these measuring devices are converted into displacements in the tape width direction. The measurement result from each measuring device is output as a voltage. This output voltage value is input to the arithmetic unit 9 and converted into a numerical value corresponding to the actual displacement. The value obtained by this calculation is taken as the tape width direction displacement. The value which is the standard of the tape width is d. When the tape width is equal to the reference value d and tape width fluctuation and waving are not performed, and the tape is run in an ideal state without vertical fluctuation, the width direction displacement is measured, and the output from each measuring device is obtained. The tape width direction displacement is ± 0. The displacement in the tape width direction is made positive in the direction from the lower end to the upper end of the tape, and the change in the light-shielding area due to the displacement of the tape end is converted by the arithmetic unit 9 to correspond to the displacement in the tape width direction. The tape width direction displacements at time t at the measurement positions A, B, and C obtained by this conversion are α (t), β (t), and γ, respectively.
(t).

Next, a method of calculating the tape width variation, the waving, and the vertical variation from the displacement in the tape width direction at the measurement positions A, B and C will be described. The tape runs at a constant speed v. Therefore, the time Δt required for the measured point on the tape which has passed the measurement position C to reach the measurement position A is Δt.
Is Δt = e / v. Therefore, the widthwise displacement α at the measurement position A at time t
The tape vertical fluctuation is determined from the widthwise displacement γ (t-Δt) at the measurement position C measured at (t) and time (t-Δt).
The measured point at the measurement position A at time t and the time (t−Δ
The measured point at the measurement point C in t) is the same. Therefore, the tape width variation and the waving have the same influence on the widthwise displacement of both. That is, even if there is tape width fluctuation or waving, if there is no tape vertical fluctuation, then α (t) = γ (t−Δt). The tape vertical fluctuation r (t) based on the tape width direction displacement at the measurement point C at time (t−Δt) is r (t) = α (t) −γ (t−Δt) = α (t) −γ (t−e / v) (1) By holding the value of γ (t-Δt) in the storage device 8 and performing this calculation by the calculation device 9, the tape vertical fluctuation r (t) can be calculated.

The tape width variation p (t) can be calculated as the difference between the upper and lower ends of the tape. Therefore, by performing the calculation of p (t) = α (t) −β (t) (2) from the widthwise displacements at the measurement position A and the measurement position B at the time t by the arithmetic unit 9, Tape width fluctuation p
(t) can be obtained.

The absolute width D (t) of the tape can be calculated as D (t) = d + p (t) = d + α (t) -β (t) by using the value d as a reference of the tape width. .

Before the waving q (t) is obtained, the center position displacement s (t) of the tape is obtained. Since the center position displacement s (t) is the average of the widthwise displacements of the upper and lower ends of the tape, it can be expressed as s (t) = {α (t) + β (t)} / 2. Since the center position displacement s (t) of the tape is a combined amount of the waving q (t) and the tape vertical fluctuation r (t), q (t) + r (t) = {α (t) + β (t)}. It becomes / 2. Therefore, the waving q (t) is q (t) = {α (t) + β (t)} / 2−r (t) = {α (t) + β (t)} / 2− {α (t) −γ (t−Δt)} = {β (t) −α (t)} / 2 + γ (t−Δt) = {β (t) −α (t)} / 2 + γ (t−e / v)・ It can be expressed as (3). By performing this calculation by the arithmetic unit 9, the waving q (t) can be calculated.

As described above, according to the tape measuring apparatus of this embodiment, the first measuring device 2 for measuring the widthwise displacement of the upper end of the tape at the measuring position A at the upper end of the tape is substantially the same as the measuring position A in the longitudinal direction. A second measuring device 4 for measuring the widthwise displacement at the measurement position B at the lower end of the tape and a third measurement for measuring the widthwise displacement at the measuring position C at the upper end of the tape at a position different in longitudinal direction from the first measuring device 2. By providing the measuring device 6, the storage device 8 that holds the value of the third measuring device 6 for a certain period of time, and the arithmetic device 9 that performs the calculation using the output value of each measuring device and the value held by the storage device. , Tape width fluctuation, waving, and vertical fluctuation can be obtained separately.

This makes it possible to classify the factors of tape width variation, which have been difficult in the past, into three categories of tape width variation, waving, and vertical variation, and to quantitatively examine them, so that more stable tape running can be achieved. It is possible to efficiently analyze the improvements to be realized.

In this embodiment, the laser beam is directly projected from the measuring device projecting portion to the light receiving portion, but the same measurement can be performed with the configuration in which the optical path is changed by using the optical fiber 15 as shown in FIG. is there. By changing the optical path curvedly,
As compared with the first embodiment, it is possible to increase the degree of freedom regarding the arrangement of the measuring devices, such as avoiding obstacles on the optical path. Therefore, even in a magnetic tape device in which it is difficult to secure a linear laser optical path, it is possible to measure the same tape width direction fluctuation.

Although a non-contact optical measuring device is used as the measuring device in the present embodiment, a contact measuring device which does not affect the tape running may be used, or an eddy current non-optical measuring device may be used. A measuring instrument of the formula may be used. In either method, the same measurement can be performed by using a measuring device that can measure the widthwise displacement of the tape.

In this embodiment, the measuring positions A and C are set to the upper end of the tape and the measuring position B is set to the lower end of the tape. However, the measuring positions A and C are set to the lower end of the tape and the measuring position B is set to the upper end of the tape. Can perform the same measurement.

Further, in the present embodiment, the widthwise displacement of the measurement positions A and B is measured by using two measuring instruments.
Similar measurement can be performed by using one measuring instrument capable of obtaining the displacement amounts of the upper and lower ends of the tape, such as the laser contour measuring instrument shown in FIG. If the tape width direction displacement at the measurement positions A, B, and C can be measured, the same measurement can be performed even when the number of measuring devices is three or more.

The second embodiment of the present invention will be described below. FIG. 6 is a perspective view of a tape measuring device showing a second embodiment of the present invention. The difference from the configuration of FIG. 1 is the following two points. First, the measurement position C of the tape width direction displacement is located at a position away from the measurement position A at the upper end of the tape by a distance e in the tape longitudinal direction in the tape traveling direction. Another point is that the storage device 8 is connected between the first measuring device 2 and the arithmetic device 9. The other configurations are the same as those in FIG.

In the tape measuring device configured as described above, the position of the first measuring device 2 is different, and the value output from the first measuring device 2 is held in the storage device 8 and input to the arithmetic device 9 The displacement in the width direction is measured in the same manner as in 1. FIG. 7 shows the measurement position of the widthwise displacement. For the tape of speed v, when the widthwise displacements at the measurement positions A, B, and C at time t are α (t), β (t), and γ (t), the tape width variation at time t, Waving and tape vertical fluctuations are calculated.
Regarding tape vertical fluctuation, measurement point A at time (t-e / v)
The calculation method based on the displacement in the tape width direction is used. Therefore, the tape vertical fluctuation based on the tape width direction displacement at the measurement point A at time (t-e / v) is: r (t) = γ (t) -α (t-e / v) (4)

The tape width variation p (t) can be calculated as the difference between the upper and lower ends of the tape. Therefore, from the displacement in the width direction at the measurement position A and the measurement position B at time t, p (t) = α (t) −β (t) (5)

Before obtaining the waving q (t), the center position displacement s (t) of the tape is obtained. Since the center position displacement s (t) is the average of the widthwise displacements of the upper and lower ends of the tape, it can be expressed as s (t) = {α (t) + β (t)} / 2. Since the center position displacement s (t) of the tape is a combined amount of the waving q (t) and the tape vertical fluctuation r (t), q (t) + r (t) = {α (t) + β (t)}. It becomes / 2. Therefore, the waving q (t) is q (t) = {α (t) + β (t)} / 2−r (t) = {α (t) + β (t)} / 2− {γ (t) −α (t−e / v)} = {α (t) + β (t)} / 2−γ (t) + α (t−e / v) (6) Therefore, tape width fluctuation, waving, and tape vertical fluctuation can be measured separately.

The third embodiment of the present invention will be described below. FIG. 8 is a perspective view of a tape measuring device showing a third embodiment of the present invention. The difference from the configuration of FIG. 1 is that the reflecting mirror 16 is installed at the laser incident position of the first measuring device light receiving part 2-2, the second measuring device light receiving part 4-2, and the third measuring device light receiving part 6-2. Is. The first measuring device light receiving unit 2-2, the second measuring device light receiving unit 4-2, and the third measuring device light receiving unit 6-2 receive the laser beam whose optical path is changed by the reflecting mirror 16 under substantially the same conditions as in FIG. Install so that you can. The other configurations are the same as those in FIG.

In the tape measuring device configured as described above, the direction of the laser beam projected from the first measuring instrument light projecting section 2-1 is changed by the reflecting mirror and is incident on the first measuring instrument light receiving section 2-2. To be done. The same applies to the second measuring device 4 and the third measuring device 6. Since the same operation as that of the first embodiment is performed except for the change of the optical path, it is possible to separately measure the tape width variation, the waving, and the tape vertical variation. Therefore,
The description of the operation of the measuring device and the method of calculating the variation in the tape width direction will be omitted.

As described above, by providing the reflecting mirror and bending the laser optical path, the light receiving portions 2-2, 4-2 of the measuring instrument,
6-2 does not need to be directly installed on the optical path of the laser projected by the light projecting units 2-1, 4-1 and 6-1 and the degree of freedom in the arrangement of the measuring device is greatly expanded. Further, since the reflecting surface of the reflecting mirror 16 only needs to have an area that completely reflects the laser beam, it can be considerably miniaturized as compared with the measuring device light receiving portion. As a result, since the measuring device light receiving portion is large, the measurement can be performed even in a magnetic tape device in which the measuring device cannot be arranged around the tape. Therefore, it is possible to measure the fluctuation in the tape width direction even inside the small-sized magnetic tape device, which has been difficult to measure in the past.

In the third embodiment, one reflecting mirror is arranged in each laser optical path, but the same measurement can be performed even if two or more reflecting mirrors are arranged. In addition to the third embodiment, by installing the reflecting mirror 16 also on the side of the measuring device projecting section, the tip of the measuring section can be made smaller. At the same time, the degree of freedom in arranging the measuring instruments can be increased.

The fourth embodiment of the present invention will be described below. FIG. 9 is a perspective view of a tape measuring device showing a fourth embodiment of the present invention. The difference from the configuration of FIG. 1 is that the first measuring device projecting section 2-1 and the light receiving section 2-2 measure the displacement in the tape width direction of the tape 1 and the second measuring device projecting section 4 -1 and the light receiving section 4-2 are arranged so that the distance in the tape width direction from the measurement position B at which the measurement is performed and the shaft 19 fixed to the measuring device base portion (not shown)
Is the point that was installed. In FIG. 10, the second measuring device projecting section 4-
1 is a perspective view of a mechanism (measuring device moving means) that makes 1 movable. As shown in FIG. 10, the second measuring device projecting section 4-1.
In addition, the hole 17 and the female screw portion 18 orthogonal to the hole 17 are provided. The hole 17 of the second measuring device projecting section 4-1 is passed through the shaft 19. The second measuring instrument projecting unit 4-1 is fixed to the shaft 19 by screwing the set screw 20 onto the female screw section 18 and crimping the tip end of the set screw 20 to the shaft 19. By loosening the crimping of the setscrew 20, the second measuring device projecting section 4-1 can be moved in the axial direction of the shaft 19, and further crimping can fix the second measuring device projecting section 4-1 at an arbitrary position.

The second measuring device light receiving section 4-2 has a similar structure so that it can move on the shaft 19.

The second measuring device projecting section 4-1 and the second measuring device receiving section 4-2 are moved in pairs, and the second measuring device projecting section 4-1 is used.
The laser beam emitted from the
It is installed so that the measuring device light receiving unit 6-2 can receive light. Therefore, the structure in which the measuring device is fixed is almost the same as that of FIG. 1, and only the distance between the first measuring device 2 and the second measuring device 4 in the tape width direction is different.

In the tape measuring device constructed as described above, the same operation as in the first embodiment is performed with the measuring device fixed, so that tape width fluctuation, waving, and tape vertical fluctuation are separately measured. It is possible. As the calculation method, the formula shown in the first embodiment can be used. Therefore, the description of the operation of the measuring device and the method of calculating the tape width variation is omitted.

In the first embodiment, the variation in the width direction can be measured for the tape 1 having a specific width, but in the present embodiment, the second measuring device projecting section 4-1 and the second measurement are performed. Receiver 4
By moving -2, it is possible to measure the variation in the width direction for the tapes 1 having various widths. Therefore, the variation in the width direction of the tape 1 can be measured with various magnetic tape devices, and the field of application is expanded.

As a method of making the measuring instrument movable, a method may be used in which the shaft 19 is changed to a rail, and a wheel portion is attached to the measuring instrument so as to move on the rail. A female screw portion may be used, and the shaft 19 may be used as a male screw portion to rotate the shaft 19 to move the screw 19 by utilizing screw engagement. As described above, various methods of moving the measuring device are conceivable. In any method, if at least one of the measuring devices can be moved in the tape width direction as in this embodiment, the same effect can be obtained. Is possible.

The fifth embodiment of the present invention will be described below. FIG. 11 is a perspective view of a tape measuring device showing a fifth embodiment of the present invention. The difference from the configuration of FIG. 1 is that the first measuring device light projecting section 2-1 and the light receiving section 2-2 measure the displacement in the tape width direction of the tape 1, and the third measuring device projecting section 6 -1 and the light receiving section 6-2 are arranged so that the distance between the measurement position C and the measurement position C where the measurement is performed can be changed, and the shaft 19 fixed to the measuring device base portion (not shown).
Is the point that was installed. In FIG. 12, the third measuring device projecting unit 6-
1 is a perspective view of a mechanism (measuring device moving means) that makes 1 movable. As shown in FIG. 12, a hole 17 is formed in the third measuring device projecting section 6-1 and a female screw portion 18 perpendicular to the hole 17 is formed.
To provide. The hole 17 of the third measuring device projecting section 6-1 is passed through the shaft 19. Set screw 20 is screwed to female screw part 18,
The third measuring device projecting section 6-1 is fixed to the shaft 19 by crimping the tip of the set screw 20 to the shaft 19. By loosening the crimping by the set screw 20, the third measuring-device light projecting section 6-1 can be moved in the axial direction of the shaft 19, and further crimping can fix the third measuring-device projecting section 6-1 at an arbitrary position. The third measuring device light receiving unit 6-2 has the same configuration. The movements of the third measuring instrument projecting section 6-1 and the third measuring instrument light receiving section 6-2 are performed in pairs, and the laser beam projected from the third measuring instrument projecting section 6-1 is almost the same as in FIG. The third measuring instrument light receiving section 6-2 is installed so that it can receive light under the same conditions. Therefore, the configuration with the measuring device fixed is shown in FIG.
The configuration is almost the same as the above, and only the distance between the first measuring device 2 and the second measuring device 4 in the tape width direction is different.

In the tape measuring device constructed as described above, the same operation as that of the first embodiment is performed with the measuring device fixed, so that tape width fluctuation, waving, and tape vertical fluctuation are measured separately. It is possible. Therefore, the description of the operation of the measuring device and the method of calculating the tape width variation is omitted.

In the first embodiment, measurement position A and measurement position C
Are fixed at a distance e. Therefore, it takes (e / v) time for the measured point of the tape having the traveling speed v to move from the measurement position C to the measurement position A. That is, the widthwise displacement of the measurement position A is the widthwise displacement observed at the measurement position C before time (e / v). Figure 1 shows the vertical movement of the tape
If the vertical fluctuation period is (e / v) when the fluctuation is sinusoidal as shown in Fig. 3, the tape width direction displacement at the two measurement positions is the same, and it is observed that there is no vertical fluctuation. It That is, in the first embodiment, there may be a case where the vertical fluctuation cannot be accurately measured due to the cycle of the tape vertical fluctuation. In the present embodiment, the measurement position C of the third measuring device is moved to the measurement position C ′ in FIG. 13 so as to pass through the peak (maximum) and valley bottom (minimum) portions of the sinusoidal vertical fluctuation. Since the widthwise displacement of the measurement point can be measured, it is possible to accurately measure the tape vertical fluctuation amount.

By moving the measurement positions of the third measuring device projecting portion 6-1 and the third measuring device light receiving portion 6-2, more accurate tape up and down fluctuation can be achieved without being affected by the cycle of tape vertical vibration. The quantity can be measured. Therefore, since it is possible to measure the tape width fluctuation corresponding to the vertical fluctuation of every cycle, it is possible to use it in various magnetic tape devices.

As a method for making the measuring instrument movable, a method may be used in which the shaft 19 is changed to a rail, and a wheel portion is attached to the measuring instrument to move on the rail. A female screw portion may be used, and the shaft 19 may be used as a male screw portion to rotate the shaft 19 to move the screw 19 by utilizing screw engagement. As described above, various methods of moving the measuring device are conceivable. In any method, the same effect can be obtained if at least one of the measuring devices can be moved in the tape longitudinal direction as in the present embodiment. Is possible.

The sixth embodiment of the present invention will be described below. FIG. 14 is a perspective view of a tape measuring device showing a sixth embodiment of the present invention. The difference from the configuration of FIG. 1 is that the tape 1 is placed before and after the first measuring device 2, the second measuring device 4, and the third measuring device 6.
The point is that the tape guide 21 that regulates the vertical movement of the tape is provided. The other configurations are the same as those in FIG.

In the tape measuring device constructed as described above, the same operation as that of the first embodiment is carried out with respect to the measurement of the variation in the width direction, and the explanation thereof will be omitted. Since the upper and lower ends of the tape 1 are regulated by the tape guides 21 installed in front of and behind the measuring instrument, vertical movement due to running of the tape between the tape guides 21 is suppressed. It also becomes possible to obtain stable tape running. In this case, one of the factors of tape width variation
Since the influence of the vertical fluctuation, which is one of the above, is small and the measurement error of the vertical fluctuation can be reduced, it is possible to obtain a more accurate value for waving as compared with the first embodiment. Vertical fluctuation is large compared to tape width fluctuation and waving, and it is particularly effective for tape width fluctuation measurement in a magnetic tape device where measurement accuracy is problematic, and improvement in waving measurement accuracy can be achieved. .

As a method of suppressing the vertical fluctuation of the tape 1, a method using a flanged post or a method using a lead-shaped guide of a cylinder may be used.
In any method, as long as the tape can be regulated, the same effect can be obtained regardless of the shape and method of the tape guide 21 and if the number is one or more.

When the tape guide 21 capable of restricting the vertical movement of the tape is installed, it is necessary to install the third measuring device 6 and measure the displacement in the tape width direction at the measurement position C. There is no.

Further, the tape guide 21 does not always need to regulate the tape 1, but may be installed so as to be detachable, and the use of the tape guide 21 may be switched depending on the object to be measured. In this case, a tape width variation and waving are measured with the tape guide 21 regulated, and a measurement method is possible in which the tape vertical variation is measured without regulation by the tape guide 21 with reference to the measured values. Become. In this case, the accuracy of all measured values can be improved.

[0065]

As described above, according to the tape measuring method and the tape measuring apparatus of the present invention, the widthwise displacement is measured at the measuring positions at the three end portions of the running tape, so that the tape is measured at a certain time t. Tape width variation, waving,
Vertical fluctuation can be calculated. This makes it possible to quantitatively analyze and compare the factors of the tape width fluctuation during running. Therefore, in order to realize stable tape running, it is analyzed whether it is necessary to reduce the tape width error related to tape width fluctuation and waving, or to improve the tape running state related to vertical fluctuation. It will be easy. Further, since it is possible to simultaneously measure the tape width variation and the waving for a running tape, which has been difficult in the past, it is possible to perform a more detailed examination of the tape width error.

Further, according to the present invention, the measuring instrument is an optical type and the optical path used for the measurement is changed, so that the degree of freedom of the arrangement of the measuring instrument main body can be widened. As a result, the tape width variation can be measured even with respect to the tape in the magnetic tape device in which the size is a problem and the measuring device cannot be arranged. Therefore, since the measurement can be performed even on a general magnetic tape device which does not assume the arrangement of the measuring device, the applicable field of the measuring device can be expanded.

Further, according to the present invention, by providing means for moving at least one of the first measuring device and the second measuring device in the tape width direction on the tape, the tape at the position where the measurement is performed is provided. The distance in the width direction can be changed.
This makes it possible to measure the variation in the width direction corresponding to various tapes having different tape widths. Therefore,
It is possible to measure variations in the tape width direction in various magnetic tape devices, and it is possible to expand the field of application of the measuring device.

Further, according to the present invention, by providing means for moving at least one of the first measuring device, the second measuring device and the third measuring device in the tape longitudinal direction, The distance in the tape longitudinal direction can be changed. As a result, it is possible to cope with a situation in which accurate measurement cannot be performed due to the cycle of vertical movement of the running tape. That is, it is possible to perform width fluctuation measurement corresponding to vertical fluctuations in every cycle.

[Brief description of drawings]

FIG. 1 is a perspective view of a tape measuring device according to a first embodiment of the present invention.

FIG. 2 is a measurement principle diagram of a measuring device according to the tape measuring device of the present invention.

FIG. 3 is a graph showing a relationship between an analog output voltage and a light shielding area.

FIG. 4 is an explanatory diagram of tape measurement according to the first embodiment of the present invention.

FIG. 5 is a perspective view of a first embodiment of the present invention using an optical fiber.

FIG. 6 is a perspective view of a tape measuring device according to a second embodiment of the present invention.

FIG. 7 is an explanatory diagram of tape measurement according to the second embodiment of the present invention.

FIG. 8 is a perspective view of a tape measuring device according to a third embodiment of the present invention.

FIG. 9 is a perspective view of a tape measuring device according to a fourth embodiment of the present invention.

FIG. 10 is a perspective view of essential parts of a measuring device moving means according to a fourth embodiment of the present invention.

FIG. 11 is a perspective view of a tape measuring device according to a fifth embodiment of the present invention.

FIG. 12 is a perspective view of essential parts of a measuring instrument moving means according to a fifth embodiment of the present invention.

13 is an explanatory diagram of sinusoidal vertical vibration of the tape and a measurement position.

FIG. 14 is a perspective view of a tape measuring device according to a sixth embodiment of the present invention.

FIG. 15: Measurement principle diagram of a conventional laser contour measuring instrument

[Explanation of symbols]

 1 Tape 2-1 Light-Emitting Unit of First Measuring Device 2-2 Light-Receiving Unit of First Measuring Device 4-1 Light-Emitting Unit of Second Measuring Device 4-2 Light-Receiving Unit of Second Measuring Device 6- 1 Light Emitting Unit of Third Measuring Instrument 6-2 Light Receiving Unit of Third Measuring Instrument 8 Storage Device 9 Computing Device 10 Laser Beam 11 Semiconductor Laser 12 Light Emitting Unit Optical System 13 Light Receiving Unit Optical System 14 Light Receiving Element 15 Optical Fiber 16 Reflector 17 Hole 18 Screw 19 Shaft 20 Set screw 21 Tape guide 22 Semiconductor laser projector 23 Polygon mirror 24 Reflective mirror 25 Collimator lens 26 Light receiving lens 27 Light receiving element 28 Edge detection device

Claims (8)

[Claims] 1. A tape running at a speed v, wherein the widthwise displacement at a time t at a measurement position A at one end in the tape width direction is α (t), and other values in the widthwise direction at the measurement position A of the tape are defined. Let β (t) be the widthwise displacement at time t at the end and the tape longitudinal position is almost the same as the measurement position A, and at the end on the same side in the tape width direction as the measurement position A, and In the longitudinal direction of the tape, the tape travels in the reverse direction e
Γ (t) is the widthwise displacement at time t at a position separated by
Tape width fluctuation p at time t at the measurement position A
(t), waving q (t), tape vertical fluctuation r (t), p (t) = α (t) −β (t) q (t) = {β (t) −α (t)} / 2 + γ (t−e / v) r (t) = α (t) −γ (t−e / v). 2. A tape traveling at a speed v, wherein the widthwise displacement at time t at a measurement position A at one end in the tape widthwise direction is α (t), and other values in the widthwise direction of the measurement position A of the tape are measured. The widthwise displacement at time t at the end and at the same position as the measuring position A where the tape longitudinal direction position is almost the same is β (t)
And the distance e in the tape traveling direction in the tape longitudinal direction at the end on the same side as the measurement position A in the tape width direction.
Γ (t) is the widthwise displacement at time t at a position separated by
Tape width fluctuation p at time t at the measurement position A
(t), waving q (t), and tape vertical fluctuation r (t), p (t) = α (t) −β (t) q (t) = {α (t) + β (t)} / 2 −γ (t) + α (t−e
/ V) r (t) = γ (t) -α (t-e / v). 3. A first measuring device that detects and outputs a widthwise displacement of one end of the tape in the width direction of the tape and a tape position measured by the first measuring device have a position substantially in the longitudinal direction of the tape. The same second measuring device that detects and outputs the widthwise displacement of the other end of the tape and the measuring position measured by the first measuring device and the second measuring device are different at positions different from each other in the tape longitudinal direction. A third measuring device that detects and outputs the widthwise displacement of the end portion of the tape, and a memory that holds at least one of the values output by the first measuring device, the second measuring device, and the third measuring device. A device, the first measuring device, the second measuring device,
A tape measuring device, comprising: an arithmetic unit for calculating at least one of tape width variation, waving, and tape vertical variation using a value output by a third measuring device and a value held by the storage device. apparatus. 4. The tape measuring device according to claim 3, wherein the first measuring device, the second measuring device and the third measuring device are non-contact optical measuring devices. 5. The tape measuring device according to claim 4, wherein a reflecting mirror is arranged on an optical path used for the measurement by the first measuring instrument, the second measuring instrument and the third measuring instrument. 6. A measuring instrument moving means is provided, and at least one of the first measuring instrument and the second measuring instrument is movable by the measuring instrument moving means in the tape width direction. The tape measuring device described. 7. A measuring device moving means is provided, and at least one of the first measuring device and the third measuring device is movable in the tape longitudinal direction by the measuring device moving means. The tape measuring device described. 8. At least one tape guide for regulating the position of the tape is provided in the vicinity of the position where the first measuring device, the second measuring device and the third measuring device measure the tape. The tape measuring device according to claim 3.