JP2001110047A - Feed stabilizing method of magnetic tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a feed stabilizing method of magnetic tape to cause no slippage despite of a high tape feeding speed, to prevent the damage and winding disturbance of the tape that are caused by the slippage and also to attain the accurate positioning of the tape in its width direction. SOLUTION: In this feed stabilizing method of a magnetic tape, the magnetic tape is fed in its lengthwise direction by a roller feed means and also positioned by a width direction feeding stabilization means of the roller feed means. For instance, a roller having a flange, a crown roller and a concave roller are used.

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 transport of a magnetic tape, which can prevent damage to the magnetic tape and disturbance of the winding appearance due to this.

[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, the tape entrains air (entrained air) and floats on the capstan roller or the like, which may cause the tape to slip, thereby preventing normal transport. .

As a result, in various manufacturing apparatuses, the tape collides with or improperly contacts a capstan roller, a guide roller, a blade blade, or the like, causing breakage of the tape or tape edge, abrasion or peeling of a magnetic layer, or the like. Tape damage occurs and the resulting tape becomes unsuitable 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.

[0006]

As described above, in order to improve the suitability for high-speed transport of the tape, it can be improved by adjusting the formulation of the back layer.
There are limits to improvement due to various prescription issues. Specifically, if the formulation of the back layer is changed, the characteristics of the magnetic tape may fluctuate, and the desired performance may not be obtained. In other words, adjusting the prescription of the back layer to improve the high-speed transport suitability of the tape while preventing a decrease in performance is a very laborious operation,
It is disadvantageous in terms of development efficiency, cost of magnetic tape, and the like.

[0007] On the other hand, the air entrained in the back layer of the magnetic tape is "escaped" to the back layer of the magnetic tape.
It is possible to eliminate the effect by making When processing such a magnetic tape into the back layer, it is necessary to accurately position the magnetic tape at the processing position. In this case, however, the above-mentioned entrained air exerts an adverse effect and the magnetic tape is accurately positioned. There is a problem that can not be.

[0008] Therefore, the magnetic tape, for example, EPC
Positioning in the width direction using a technique called (edge position control) is effective. However, in the conventional EPC technique, when conveying a web such as a tape, the angle of at least one roller is set. By changing, the so-called steering effect is used, and this method has another problem that the structure becomes complicated and a large space is required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to prevent a slip or the like from occurring even when a magnetic tape is conveyed at a high speed, thereby causing damage or damage to the magnetic tape. It is an object of the present invention to provide a method for stabilizing the transport of a magnetic tape, which can prevent the disorder of the winding shape and can accurately position the tape in the width direction.

[0010] More specifically, an object of the present invention is to provide a magnetic tape processing apparatus and the like, which is capable of positioning the magnetic tape in the width direction with a simple configuration.
An object of the present invention is to provide a method for stabilizing the transport of a magnetic tape.

[0011]

In order to achieve the above object, a method for stabilizing the transport of a magnetic tape according to the present invention comprises the steps of: And the positioning is performed by the widthwise conveyance stabilizing means of the roller conveying means. Here, it is preferable that the positioning is performed by a width-direction position regulating collar of the roller transporting unit or by a self-correcting function of the roller transporting unit.

Further, in the method for stabilizing the transport of a magnetic tape according to the present invention, the roller transport means for transporting the magnetic tape may be provided as an apparatus having, at both ends thereof, a flange for positioning the magnetic tape in the width direction. Can be Here, it is preferable that the spacing between the brims at both ends of the brim is slightly smaller than the width of the magnetic tape.

An apparatus embodying another method for stabilizing the transport of a magnetic tape according to the present invention is characterized in that the roller transport means for transporting the magnetic tape has a self-correcting function. Here, the roller conveying means having the self-correcting function is preferably a crown roller or a concave roller.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for stabilizing the transport of a magnetic tape according to the present invention will be described in detail based on a preferred embodiment 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. Of the present invention is applied to a tape transport control unit of a magnetic tape processing device (hereinafter, also simply referred to as a processing device).

Here, the magnetic tape to which the transport stabilizing 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 structure having an undercoat layer and an undercoat layer may be used, and the back layer is subjected to the above-described processing for creating an “escape” for the entrained air as described above.

FIG. 1 conceptually shows an example of a back layer of a magnetic tape processed by the tape processing apparatus according to the present embodiment. In the example shown in FIG. 1A, a plurality of processing lines a extending in the longitudinal direction of the tape are provided on the back layer of the tape.
It is formed. The example shown in FIG.
In the example shown in FIG. 1 (A), the processing of the back layer is intermittent, and the processing line is divided (shown by b). 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 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 due to the capstan roller or the like of the manufacturing apparatus and does not slip, and 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. Generally, the tape width, the material and thickness of the back layer, the material and thickness of the base, the steps 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 is a conceptual diagram of a tape processing apparatus for producing such a magnetic tape by using a processing method using a laser beam. The illustrated tape processing device 1
Numeral 0 forms a processing line extending in the longitudinal direction of the tape as shown in FIGS. 1A and 1B, and includes a light source 12 for emitting a laser beam, a pulse modulator 14, The optical system includes a mirror 16, a beam expander 18, a beam profiler 20, and a multi-lens 22, and a tape transport unit 24.

In such a tape processing apparatus 10, the (magnetic) tape T is ejected from the light source 12 while being transported in the longitudinal direction (the direction of the arrow x in the drawing) while being positioned at a predetermined processing position by the tape transport means 24. The processed laser beam is incident on the processing position by an optical system, thereby forming a processing line on the tape. Here, the tape T is
The back layer is transported upward (toward the laser beam incident side), and therefore, the tape T
Of the back layer is processed.

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 range 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 performs pulse modulation of a laser beam in order to form a processing line 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 tape processing apparatus 10 according to the present embodiment divides one laser beam to form a processing line on the tape T.
It is preferable that processing lines can be formed on the entire surface in the width direction corresponding to tapes T of various widths. However, in general, the diameter of the laser beam emitted from the light source is 1 mm
Since the width of the tape T is wider than that, it is impossible to process the entire surface of the tape T 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 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 light 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 is made up of flanged rollers 30a and 30b, which will be described later, and comes into contact with the surface (magnetic layer side) of the tape T to be conveyed to place the tape T at a predetermined processing position. (Hold). The tape T is moved in the conveying direction x by
Guide rollers 26 and 28 disposed so as to sandwich a and 30b 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-described 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 flanged rollers 30a and 30b constituting the tape flattener 30 are required to position the tape T with high accuracy, preferably with an error of about 10 μm, 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 if necessary, reflected by the mirror 16, expanded in diameter 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.

Therefore, with the tape conveying means 24, the flanged rollers 30a, 30a constituting the tape flattener 30 with the back side facing upstream of the laser beam optical path.
The tape T is transported in the longitudinal direction while being positioned at the processing position by b, so that the back layer of the tape T
A processing line (recess) extending in the longitudinal direction is formed. In the above-described example, 25 processing lines are formed by one transfer. Here, the fact that the conveyance stability in the width direction is important is as described below.

Further, in the tape processing apparatus 10, there are many cases where processing dust such as dust or gas is generated by processing the back layer of the tape T. Therefore, it is preferable to provide a removing means for removing the above-mentioned processing residue and gas near the processing position. Further, it is preferable to provide a cleaning means downstream of the processing position for removing at least the foreign matter attached to at least the back surface (back layer surface), preferably the front and back surfaces of the tape T.

FIG. 5 shows a first embodiment of a means for positioning the tape T at a predetermined processing position (hereinafter referred to as a tape positioning unit) in the tape processing apparatus 10. FIG. 5 is a side sectional view of the ribbed rollers 30a and 30b constituting the tape flattener 30 in FIG. In FIG. 5, reference numeral 31 denotes a collar provided at both ends of the flanged rollers 30a and 30b and having a height of about 1 mm to 3 mm.

The collar rollers 30a, 30b
Has a width (surface length) slightly smaller than the width of the tape T, and has curved end portions 32 at both ends as shown in FIG. The curvature of the curved surface processing portion 32 is appropriately determined based on the type and thickness of the tape T.

The surface length of the flanged rollers 30a and 30b is slightly (specifically, for example, about 1%) smaller than the tape width. When the surface lengths of the attached rollers 30a and 30b are the same as the tape width, as shown in FIGS. 7A and 7B, the initially flat roller surface (see FIG. 7A)
In order to prevent the tapes T from being damaged due to the formation of dents 33 at both ends due to wear (see FIG. 7B).

The surface shape of both ends of the flanged rollers 30a and 30b is processed into a curved surface as shown in FIG. 6 so that both sides of the flanged rollers 30a and 30b are narrower than the width of the tape T. Tape T between ends of brim
This has the effect of improving the familiarity of the user.

According to the configuration of the tape positioning section shown in the above embodiment, the magnetic tape can be positioned at a fixed position in the width direction of the magnetic tape with a simple configuration, which can be suitably applied to various processing apparatuses for processing a magnetic tape. And a magnetic tape transport stabilizing device capable of performing the above-described operations.

FIGS. 8A and 8B show a second embodiment of the tape positioning unit. FIG. 8A shows a guide roller in front of the tape flattener 30 composed of the sapphire blades 30c and 30d, which is a so-called crown roller having a central portion whose diameter is enlarged (FIG. 8).
(Refer to (B)). It is characterized in that it is constituted by combining two of them.

As is well known, the diameter of the crown roller 40 is larger at the center than at both ends, that is, D ₁ > d ₁ , and conveys the web. When used in this case, even when a positional deviation (meandering) in the left-right direction of the web occurs, this deviation is automatically corrected. Here, the crown roller 40 is
In order to ensure the effect, it is preferable to use at least two pairs.

As shown in both figures, the tape positioning section according to the present embodiment has a first roller provided with a crown roller 40 in place of the flanged rollers 30a and 30b shown in the first embodiment. As in the embodiment, in addition to being able to position the magnetic tape at a fixed position in the width direction, there is an advantage that the configuration of the positioning mechanism can be further simplified.

FIGS. 9A and 9B show a third embodiment of the tape positioning unit. FIG. 9 (A) shows FIG.
A sapphire blade 30c similar to that shown in FIG.
The guide roller at the front stage of the tape flattener 30 composed of the tape flattener 30d is replaced with a roller whose central portion is reduced in diameter (FIG. 9B).
(Referred to as a concave roller) 50 in combination.

As is well known, the concave roller 50 also has a configuration in which the diameter at the center is smaller than the diameter at both ends, that is, D ₂ <d ₂ , and conveys the web. When used in this case, even when a positional deviation (meandering) in the left-right direction of the web occurs, this deviation is automatically corrected. It is preferable to use at least two pairs of the concave rollers 50 in order to further ensure the effect.

The same effect as that obtained by the first and second embodiments described above can also be obtained by the tape positioning section according to the present embodiment. Needless to say, the means shown in the first, second, and third embodiments may be used in an appropriate combination as long as they do not conflict.

The method for stabilizing the transport of the magnetic tape according to the present invention has been described above in detail. However, the present invention should not be limited to each of the above-described embodiments. It goes without saying that various improvements and changes may be made.

[0051]

As described above in detail, according to the tape transport stabilizing method according to the present invention, in a magnetic tape manufacturing apparatus such as a blade machine or a winder, even if the transport speed is increased, the capstan There is no slippage caused by rollers or the like, so that high-speed and accurate conveyance can be performed.

[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 processing the tape; FIGS.

FIGS. 2A, 2B, and 2C are diagrams each showing a cross-sectional shape of a processing line (recess) formed on a back layer of the tape by processing the tape;

FIG. 3 is a configuration diagram illustrating a main part of a tape processing device to which a magnetic tape positioning method according to an embodiment of the present invention is applied;

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

FIG. 5 is a diagram illustrating a configuration example of a tape positioning unit according to the first embodiment.

FIG. 6 shows a roller 3 with a collar in the embodiment shown in FIG.
It is a side view of 0a, 30b.

FIG. 7A is a diagram showing an initial state of a flanged roller, and FIG. 7B is a diagram showing a worn state.

8A and 8B are diagrams illustrating a configuration example of a tape positioning unit according to a second embodiment, where FIG. 8A is an overall configuration diagram and FIG.
FIG. 4 is a side view showing a crown roller.

FIG. 9 is a diagram illustrating a configuration example of a tape positioning unit according to a third embodiment, where (A) is an overall configuration diagram and (B).
FIG. 3 is a side view showing a concave roller.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Processing apparatus 12 Light source 14 Pulse modulator 16 Mirror 18 Beam expander 20 (Beam profile) shaper 22 Multi-lens 24 Tape transport means 26, 28 Guide roller 30 Tape flatner 30a, 30b Flanged roller 30c, 30d Sapphire blade 31 brim 32 curved surface processing part 40 crown roller 50 concave roller

Claims (1)

[Claims] 1. A method for stabilizing the transport of a magnetic tape in a longitudinal direction, wherein the magnetic tape is transported by a roller transport unit, and the magnetic tape is transported by a width transport stabilizing unit of the roller transport unit. A method for stabilizing the transfer of a magnetic tape, comprising positioning.