JP2001101655A - Method and device for stabilizing transportation of magnet tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device effective for stabilizing transportation of a magnetic tape such that the tape to be worked is positioned with extreme precision at the focal position of a machining laser beam, for example in the case of machining where a laser beam or the like is made incident on the back layer of a magnetic tape to form a recessed part (groove) on this back layer. SOLUTION: In the method for stabilizing the transportation of a magnetic tape in the longitudinal direction, a tape guiding part is energized to a reference position and the magnetic tape is transported through the guiding part so energized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of magnetic tapes used for recording / reproducing information, and more specifically, slips are generated even when a magnetic tape is transported at a high speed in a magnetic tape manufacturing process or the like. In addition, the present invention relates to a method for stabilizing the transfer of a magnetic tape and an apparatus therefor, which can prevent damage to the magnetic tape and disturbance of the winding appearance due to the above.

[0002]

2. Description of the Related Art Magnetic tapes used for recording / reproducing information are:
Basically, a base made of a film such as PET (polyethylene terephthalate), a magnetic layer formed on one surface of the base, and a magnetic layer formed on the base for the purpose of improving transport stability and strength. And a back layer formed on the opposite surface.

In the manufacturing process of such a magnetic tape, the magnetic tape (hereinafter, also simply referred to as a tape) is subjected to various processes such as cutting by a slitter and cleaning of a surface by a blade while being conveyed in a longitudinal direction. Then, it is wound up by a hub or the like to be a pancake or a cassette, and sent to the next process or a delivery destination. In recent years, in order to improve productivity, a tape transport speed in various processes (a manufacturing device such as a blade machine or a winder) tends to increase.

[0004] In general, the tape is conveyed by winding the tape around a capstan roller and rotating the capstan roller. However, when the transport speed of the tape is increased, in a manufacturing device such as a blade machine, the tape entrains air, and the tape floats with a capstan roller or the like, which causes the tape to slip, thereby preventing normal transport. In some cases.

As a result, the tape becomes a capstan roller,
The tape collides or improperly contacts the guide roller, blade blade, etc., causing tape damage such as breakage of the tape or tape edge, abrasion or peeling of the magnetic material layer, etc.
It will be inappropriate as a product. A roller for measuring the length of the tape (measurement roller) is attached to the tape manufacturing device as needed. If the tape slips with this measurement roller, an error occurs in the tape length measurement. This causes a problem that production control cannot be performed properly. For this reason, it has been difficult to increase the tape transport speed in tape manufacturing so as to favorably meet the required production efficiency.

As another problem of the magnetic tape, the above-mentioned cupping is known. Cupping is a curl (curvature) in the width direction of a magnetic tape, which is mainly caused by a difference in shrinkage of a binder used between a magnetic layer and a back layer. When cupping occurs, the appearance of the magnetic tape as a product is deteriorated; the contact of the magnetic tape with the recording head and the reading head is deteriorated, which may cause a recording error or a reading error; and the edge of the magnetic tape is easily damaged. The durability is lowered, and various problems occur.

[0007]

Such cupping can be improved by a method such as increasing the thickness of the magnetic layer, reducing the thickness of the back layer, or adjusting the formulation of the magnetic layer or the back layer. There is a limit to improvement due to various problems such as process, formulation, and performance. Specifically, in recent years, the recording density of magnetic tapes has been improving, and in order to achieve this, the thickness of the magnetic layer has been decreasing and the thickness of the backing layer has been reduced. And the problem arises in practical durability. Further, if the prescription of the magnetic layer or the back layer is changed, the characteristics as a magnetic tape fluctuate, and the desired performance may not be obtained. In other words, to reduce the cupping by adjusting the prescription of the magnetic layer and the back layer while preventing the performance from deteriorating is a very time-consuming operation, and it is necessary to reduce the development efficiency and the cost of the magnetic tape. Is disadvantageous.

As another method, it is conceivable to provide a concave portion (groove) in the back layer of the magnetic tape. However, when this method is adopted, a laser beam or the like is applied to the magnetic tape in an actual manufacturing process. In order to maintain processing accuracy when performing processing for forming concave portions (grooves) by making light incident on the back layer, the magnetic tape to be processed must be extremely accurately positioned at the focal position of the processing laser beam. is necessary.

The present invention has been made in view of the above circumstances, and an object thereof is to make a laser beam or the like incident on a back layer of a magnetic tape and to form a recess (groove) in the back layer of the tape. An object of the present invention is to provide a magnetic tape transport stabilization method and an apparatus therefor that are effective for positioning a magnetic tape to be processed at the focal position of a processing laser beam very accurately, for example, when performing forming processing.

[0010]

In order to achieve the above object, a method for stabilizing the transfer of a magnetic tape according to the present invention is a method for stabilizing the transfer of a magnetic tape in a longitudinal direction, the method comprising: The magnetic tape transport guide portion for guiding the tape is biased toward a reference position, and the magnetic tape is transported via the biased magnetic tape transport guide portion.

A magnetic tape transport stabilizing device according to the present invention is a transport stabilizing device for transporting a magnetic tape in a longitudinal direction, wherein a magnetic tape transport guide portion of the device for handling the magnetic tape is swung. The magnetic tape transport guide portion is configured to be biased toward a predetermined reference position of a device that handles the magnetic tape.

In the magnetic tape transport stabilizing apparatus according to the present invention, the predetermined reference position of the apparatus for handling the magnetic tape is preferably a processing stage for performing a predetermined process on the magnetic tape. . Further, it is preferable that the magnetic tape transport guide portion includes at least a tape supporting means for supporting the magnetic tape.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for stabilizing the transport of a magnetic tape and an apparatus therefor according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings. In the embodiments described below, the present invention is applied to a process of forming a concave portion (groove) in a back layer of a magnetic tape by irradiating a laser beam or the like to the back layer of the magnetic tape as described above. For a magnetic tape processing device (hereinafter, also simply referred to as a processing device) for application to a tape transport control unit.

Here, the magnetic tape to which the transport stabilization method according to the present invention can be applied has a magnetic layer on one surface of a base made of PET or aramid resin, and a back layer on the other surface. Alternatively, overcoat layer (protective layer)
A magnetic tape having an ordinary layer configuration, which has a magnetic layer and an undercoat layer, may be used.

FIG. 1 conceptually shows an example of a back layer of a magnetic tape processed by a tape processing device in a magnetic tape handling device according to this embodiment. In the example shown in FIG. 1A, a plurality of processing lines a extending in the longitudinal direction of the tape are formed on the back layer of the tape.
The example shown in FIG. 1B is an example in which the processing of the back layer is intermittent and the processing line is divided (shown by b) in the example shown in FIG. 1A. Here, the length of the processing line segment b is not particularly limited. Further, the lengths of the processing line segments b may be the same, or line segments having different lengths may be mixed.

A tape having a concave portion (processed line, processed line segment) in the back layer as shown in FIG. 1 also has less cupping, which is curl in the width direction of the tape, than the conventional tape. As a result, deterioration in appearance, deterioration of head contact, damage to the tape edge, and the like due to the above-mentioned problems are greatly reduced as compared with the conventional tape. Furthermore, even when the tape is conveyed at a high speed in a tape manufacturing apparatus such as a blade machine or a winder, the entrainment of air by the tape is reduced, and even when air is entrained, the air is suitably removed from the processing line. be able to.

Further, even when the tape is transported at high speed, the tape does not rise and slip due to the capstan roller or the like of the manufacturing apparatus, so that there is no damage to the tape or an error in the transport length. By performing appropriate tape conveyance, magnetic tapes of appropriate quality can be stably and efficiently manufactured under appropriate production management. Also, when rewinding,
Since the air between the tapes can be suitably removed, the appearance of the roll when wound on a cartridge or pancake is also beautiful.

There is no particular limitation on the shape (cross-sectional shape) of the above-mentioned concave portion. For example, a rectangular shape as shown in FIG. 2A, a triangular shape as shown in FIG. C)
And a semicircle (bow) as shown in FIG. These shapes can be realized by adjusting the intensity distribution (profile) of the beam spot of the laser beam used when processing the back layer.

There is also no particular limitation on the depth of the concave portion. In general, the tape width, the material and thickness of the back layer, the material and thickness of the base, the process after the concave portion formation and the user's point of view. In consideration of the load (transport speed, tension, etc.) on the tape such as the processing of
It may be determined appropriately. As an example, the depth of the recess is
0.1 μm or more, particularly preferably 0.2 μm
It is more preferable to make the above.

Further, the size (line width) and formation density of the concave portion are not particularly limited, and may be appropriately determined according to the strength and width (size) of the tape. When forming a processing line or the like extending in the longitudinal direction as shown in FIGS.
It is preferable to form several to about 100 processing lines in the width direction with a width of about 3 μm to 10 μm.

FIG. 3 shows a conceptual diagram of a tape processing apparatus used for producing the above-described magnetic tape. The processing apparatus 10 in the illustrated example is similar to the processing apparatus 10 shown in FIGS.
A light source 12 for forming a processing line extending in the longitudinal direction of the tape as shown in FIG.
And an optical system including a pulse modulator 14, a mirror 16, a beam expander 18, a beam profile shaper 20, and a multi-lens lens 22, and a tape transport unit 24.

In such a processing apparatus 10, the (magnetic) tape T is emitted from the light source 12 while being transported in the longitudinal direction (the direction of the arrow x in the figure) while the (magnetic) tape T is positioned at a predetermined processing position by the tape transport means 24. A processing line is formed on the tape by irradiating the laser beam to the processing position by an optical system. Here, the tape T is transported with its back layer facing upward (toward the laser beam incidence side), and accordingly, the back layer of the tape T is processed by the laser beam.

As the light source 12, any light source (laser oscillator) can be used as long as it has an output capable of processing the back layer of the tape T. Preferably, a laser beam in the ultraviolet or visible region is used. One that can emit at least one is used. From the viewpoint of workability, a laser beam having a short wavelength is preferable, and a laser beam in the ultraviolet region is most preferable. However, a laser beam in the visible region is preferable in terms of cost, safety, workability, and the like. In particular,
A light source that emits a 532 nm laser beam obtained by wavelength-converting an 488 nm or 515 nm argon (ion) laser or a YAG laser with an SHG (second harmonic generation) element is exemplified.

The pulse modulator 14 modulates the pulse of the laser beam in order to form a processing line segment as shown in FIG. Therefore, when the light source 12 can directly perform pulse modulation or when only the processing line as shown in FIG. 1A is formed, the pulse modulator 14 is unnecessary. As the pulse modulator 14, known modulation means such as an AOM (acoustic optical modulator) can be used. Further, by adjusting the modulation period, the length of the processing line segment can be adjusted.

The laser beam is reflected by the mirror 16 in a predetermined direction, and then enters the beam expander 18. The processing apparatus 10 according to the present embodiment divides one laser beam to form a processing line on the tape T, but applies the processing line to the entire surface in the width direction corresponding to the tape T having various widths. Preferably it is formable. However, in general, the diameter of the laser beam emitted from the light source is about 1 mm, and the width of the tape T is wider than that, so that the entire surface of the tape T in the width direction cannot be processed as it is.

For this reason, in the processing apparatus 10, the beam expander 18 is arranged to expand the diameter of the laser beam emitted from the light source 12. For example, when the diameter of the laser beam emitted from the light source 12 is 1 mm and the width of the tape T is 0.5 inch, the diameter of the laser beam may be increased about 15 to 20 times. Further, it is preferable that the diameter expansion rate of the laser beam in the beam expander 18 is adjustable.

The laser beam expanded in diameter by the beam expander 18 is then transmitted to a beam profiler 20.
(Hereinafter, simply referred to as a molding device 20). Molding machine 2
0 makes the intensity of the laser beam substantially uniform over the entire beam spot, that is, makes the intensity distribution of the laser beam substantially uniform.

Normally, since the laser beam emitted from the light source 12 has an intensity distribution such as a Gaussian distribution,
When the tape T is processed by this laser beam, the depth of the processing line varies depending on the intensity distribution. Therefore, by disposing the molding device 20, the intensity distribution of the laser beam can be made uniform, and the depth of the processing line to be formed can be made uniform. As the forming device 20, various optical filters, an aperture having the same diameter as a laser beam for forming a beam profile using Fresnel diffraction, a multi-lens lens, and the like can be used.

The laser beam is then applied to the multi-lens 22
Incident on. The multi-lens lens 22 is formed by arranging a large number of microball lenses and selfoc lenses in a direction perpendicular to the optical axis with its optical axis parallel to the laser beam. The laser beam is divided, incident on a predetermined processing position, and imaged. Thus, the back layer of the tape T is processed by the laser beam to form a processing line or the like (recess).

FIG. 4 is a schematic diagram showing one example of the structure viewed from the optical axis direction. The multi-lens lens 22 in the illustrated example is, for example, a microball lens or a selfoc lens (hereinafter, both are collectively referred to as a lens) in which 5 × 5 lenses are arranged in a close-packed state, as shown in FIG. As described above, the lens arrangement line indicated by the alternate long and short dash line is arranged with a slight inclination with respect to the transport direction x and the width direction of the tape T.
Thereby, the tape T is transported once in the longitudinal direction (one pass).
By simply doing so, a total of 25 (rows) processing lines a extending in the longitudinal direction can be formed.

Here, the distance between the processing lines a can be adjusted by adjusting the angle between the transport direction x and the lens arrangement line, but in order to form the processing lines efficiently,
This angle is the optical axis of each lens (the center of the beam waist)
Must be set so as not to overlap in the transport direction x.
For example, when paying attention to the lens arrangement line in the width direction of the tape T, if the number of multi-lens lenses in one row is N; and the angle between the transport direction x and the arrangement line is θ; Means that the optical axes of the lenses do not overlap in the transport direction x. sin [(2π / 3) + θ] ≧ N · sin θ Note that the lens arrangement of the multi-lens is not limited to the close-packed state shown in FIG. 4, and various types can be used.

In the processing apparatus 10 shown in FIG. 3, the tape T is moved to a predetermined processing position by the tape transport means 24 so that the back layer side (back side) faces upstream (laser beam incident side) of the laser beam optical path. (That is, the transport direction x and the longitudinal direction are matched) while being transported in the longitudinal direction. The tape transport means 24 includes transport drive means (not shown) such as a capstan roller, a rewinder, and a winder; guide rollers 26 and 28;
And a tape flattener 30.

The tape flattener 30 abuts on the surface (magnetic layer side) of the tape T to be conveyed, and positions (holds) the tape T at a predetermined processing position. Tape T
The guide rollers 26 and 28 arranged in the transport direction x with the tape flattener 30 interposed therebetween form a transport path that passes below the tape flattener 30. As a result, the tape T is pressed and supported by the tape flattener 30, and is positioned at the processing position.

In the tape processing apparatus 10 according to the present embodiment, the processing by the laser beam is performed with a width of 3 μm to 10 μm as described in the above-mentioned example of the tape T having a width of 0.5 inch.
Since the processing is fine processing such as μm, the beam spot diameter incident on the processing position is small, that is, the allowable range of the beam waist is very narrow. Therefore, the tape flattener 30 is required to position the tape T with high accuracy, preferably with an error of 10 μm or less, in the depth of focus direction of the multi-lens 22.

As described above, the light is emitted from the light source 12 at the processing position, modulated by the pulse modulator 14 as necessary, reflected by the mirror 16, expanded by the beam expander 18, and expanded by the forming device 20. The intensity distribution is made uniform, and a laser beam divided and modulated by the multi-lens lens 22 enters and forms an image.

Accordingly, the tape T is conveyed in the longitudinal direction by the tape conveyer 24 while the tape T is conveyed in the longitudinal direction while being positioned at the processing position by the tape flattener 30 with the back surface facing upstream of the laser beam optical path. Processing lines (concave portions) extending in the longitudinal direction are formed in the back layer, and in the above-described example, 25 processing lines are formed by one transfer.

In the tape processing apparatus 10, the tape T
In many cases, the processing of the back layer generates processing dust and gas such as dust. Therefore, in the vicinity of the processing position, a removing unit for removing the above-described processing waste and gas,
For example, it is desirable to provide a dust removing unit including an ion wind blowing unit and a suction unit for inhaling dust and the like that have been separated and floated by the ion wind.

As described above, when the laser beam is made incident on the back layer of the tape T to form a concave portion (a groove, a processing line or a processing line segment), the processing accuracy is maintained. In addition, it is necessary to extremely accurately position the tape T to be processed at the focal position of the laser beam. FIG. 5 shows details of the tape transport control unit in the processing apparatus for this purpose.

In FIG. 5, reference numeral 102 denotes a tape transport supporting portion for supporting the above-described tape flatner 30, which supports the tape flatner 30 via at least four springs 102a. Although not shown, the tape flattener 30 and the tape transport support 1
Position regulation means for maintaining the planar positional relationship with the base 02 constant is also provided.

The tape flattener 30 is, here,
It is composed of rollers 30a and 30b for supporting the tape T and a base 30c for supporting these rollers 30a and 30b. The rollers 30a and 30b are connected to the main body of the apparatus by the above-described spring 102a via the tape T. It is urged so as to come into contact with the fixed rollers 104a and 104b (urging force: f _A ).

Here, in FIG.
The force by which the tape flattener 30 is pushed down is f_T,
The tape 102 is moved from the tape flattener 30 by the spring 102a.
The force applied to the rollers 104a and 104b is represented by f_B(F_B= F_A
−f_T), Then f_A> F _TAnd f_A≒ f_TIn
If f_Bと な り 0, low from tape flattener 30
Forces applied to the rollers 104a and 104b are extremely small.
Of the rollers 104a and 104b for determining the height position of the
Wear is negligible.

The tape transport controller of the present embodiment having the above-described configuration is configured so that the tape flattener 30 always contacts the rollers 104a and 104b fixed to the apparatus main body, although the tape flatner 30 is driven by a small force. Because of being biased, the tape T of the tape flattener 30
Has a function of keeping the position of the tape T constant irrespective of the fluctuation even when the position of the rollers 30a and 30b supporting the tape T changes.

That is, for example, the tape transport controller of the present embodiment controls the tape flattener 30 (specifically, the roller 30) by continuously transporting the tape T at a high speed.
a, 30b) has an effect that it is not necessary to control the position of the tape T even when it is worn. It should be noted that although there are other possible causes of the change in the position of the tape T, the tape transport control unit according to the present embodiment can cope with any cause of the change in the position of the tape T.

According to the above embodiment, when the tape T is processed while being transported in the longitudinal direction, the tape position automatic correction function of the tape transport control unit is operated to change the position of the tape T at the processing position. Can be automatically corrected.

In the above embodiment, the target on which the tape position correcting function is applied is substantially limited to the tape flattener 30, but this is the size (may be referred to as mass) as the control target. Is appropriate, and the present invention should not be limited to this. Further, since the moving distance of the tape flattener 30 is actually extremely small, no change is required for the front and rear tape guide rollers.

The above embodiments are merely examples of the present invention, and the present invention is not limited to these embodiments. For example, the automatic correction function in the tape transport control unit for performing the automatic correction of the position of the tape T also includes various correction mechanisms such as a correction mechanism using another automatic position adjustment method other than the push-up method using the spring described in the embodiment. It goes without saying that alterations in these configurations may be made freely without departing from the scope of the present invention, as alternative means are available. Specifically, the rollers 30a,
30b, 104a and 104b may be fixed guides or a combination of rollers and fixed guides.

[0047]

As described above in detail, according to the tape transport stabilizing method and the apparatus therefor according to the present invention, a laser beam or the like is incident on the back layer of the magnetic tape, and the tape is backed. When a process of forming a concave portion (groove) in a layer is performed, an effect is obtained that a magnetic tape to be processed can be extremely accurately positioned at a focal position of a processing laser beam.

[Brief description of the drawings]

FIGS. 1A and 1B are diagrams each showing an example of a processing line (recess) formed on a back layer of a tape by a tape processing method according to the present invention.

FIGS. 2A, 2B and 2C are cross-sectional views of processing lines (recesses) formed in a back layer of the tape by the tape processing method according to the present invention.

FIG. 3 is a conceptual diagram showing a main part of a tape processing device to which the present invention is applied.

4 is a conceptual diagram for explaining a multi-lens used in the magnetic tape processing device shown in FIG.

FIG. 5 is a diagram illustrating a configuration of a magnetic tape transport control unit according to the embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 (tape) processing device 12 light source 14 pulse modulator 16 mirror 18 beam expander 20 (beam profile) forming device 22 multi-lens lens 24 tape transport means 26, 28 guide roller 30 tape flatner 30a, 30b roller 30c base 102 tape Conveyance support part 102a Spring 104a, 104b Roller on main unit side

Claims (2)

[Claims] 1. A method for stabilizing the conveyance of a magnetic tape in the longitudinal direction, comprising: urging a magnetic tape conveyance guide portion for guiding the magnetic tape toward a reference position; Transporting the magnetic tape through a magnetic tape transport guide portion. 2. A transport stabilizing device for transporting a magnetic tape in a longitudinal direction, wherein a magnetic tape transport guide portion of an apparatus for handling the magnetic tape is swingable, and the magnetic tape transport guide portion is moved. A magnetic tape transport stabilizing device configured to be urged toward a predetermined reference position of the magnetic tape handling device.