JP2003346454A - Method for manufacturing pancake - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing pancake which is capable of winding up a magnetic tape to a hub of a cassette for shipping with a good winding style and can remarkably improve productivity and the yield of products. <P>SOLUTION: The method for manufacturing the pancake comprises taking up the magnetic tape 1 delivered from a magnetic tape supply source on the hub 2 by means of a tape supply mechanism 50 for guiding the magnetic tape around the hub 2. The magnetic tape 1 is taken up on the hub 2 by the tape supply mechanism 50 which is arranged to face the hub by intersecting the axial center of the hub 2 and the axial center of a cylindrical surface disposed at the front end of the mechanism with each other at an intersection angle of 0.02 to 2°, by which the magnetic tape section of the pancake is provided with the permanent set for bending. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing pancakes (tape winding bodies in which a magnetic tape is wound around a hub), and in particular, pans for computer data backup including cassette tapes and video tapes. The present invention relates to a method for producing a cake.

[0002]

2. Description of the Related Art Various pancakes (tape rolls in which a magnetic tape is wound around a hub) used for computer data backup, such as cassette tapes and video tapes, are wound into a roll. The wide strip-shaped magnetic tape material that has been cut is cut into a plurality of narrow magnetic tapes at the cutting part while being pulled out from the delivery side and conveyed,
It is manufactured by winding on a flangeless type hub on the winding side.

A tape winding body in which a magnetic tape is wound around such a hub is generally called pancake in the industry as described above. Since this pancake is subjected to various processes, it is often rewound several times and is often shipped in a cassette as a final shipping form.

[0004]

However, if the winding shape of the magnetic tape in the form wound on the cassette is not good, the edge of the magnetic tape is broken during transportation, or the magnetic tape is used in a magnetic reproducing apparatus or the like. In doing so, there is a problem that the running performance of the magnetic tape deteriorates. In other words, the winding form of the magnetic tape in the form wound in the cassette is
Influenced by the winding shape in the magnetic tape manufacturing process.

The magnetic tape cut by the cutting section is wound on the winding hub at a high speed, and more than one must be wound at a time, so that it is difficult to obtain the mechanical accuracy of winding.
For this reason, the winding surface of the magnetic tape wound on the winding core on the winding side of the cutting device is not neatly wound and is easily wound in a slightly shifted state, so that it often has a curl.

In addition, the magnetic tape raw material cut by the cutting part has a thickness at the center of the roll rather than the thickness at both ends of the roll in order to improve the winding quality in the winding process for manufacturing the magnetic tape raw material. Is wound in a thick medium-high roll shape, and the cut magnetic tape is likely to have curled wrinkles along the longitudinal direction as shown in FIGS. 5 (a) and 5 (b).

As shown in the figure, the degree of bending is expressed by a bending width D with respect to a predetermined linear length L when the magnetic tape is placed on a flat surface. As for this curvature, in a state where it is wound in a cassette as a final shipment form, the magnetic tape wound body has a convex shape upward, and the concave shape has a positive shape.

The magnetic tape 1 cut from the medium-high roll-shaped magnetic tape material has a different curved shape depending on the width direction portion of the magnetic tape material to be collected. Then, the curve in the + direction shown in FIG. 5A may be in the state of being wound in the cassette as the final shipment form, and there is almost no curve and curve in the − direction shown in FIG. 5B. Things are considered bad.

When the pancake 3 is manufactured by winding the magnetic tape 1 having a curl to the hub 2, the magnetic tape 1 having a curvature in the + direction in the state of being wound in the cassette 4 is shown in FIG. The magnetic tape 1 having a curvature in the − direction has the shape shown in FIG.

As described above, due to the medium-high roll shape of the magnetic tape material, the curve in the + direction, the curve in the-direction,
And the thing without the curvature extract | collected from the width direction center part vicinity of the magnetic tape original fabric arises. These occur at a substantially constant probability due to the medium-high roll shape, the thickness unevenness of the magnetic tape base, and the like, and it is not possible to manufacture only those having a preferable curvature in the + direction. For this reason, in order to manufacture only those having a curvature in the + direction, a sorting step and a rewinding step are required.

As a technique for manufacturing only such a preferable curve in the + direction, for example, see Japanese Patent Laid-Open No. 9-13.
As disclosed in Japanese Patent No. 8945, means for coping with forming a tapered winding surface with a different shaft diameter from one end side to the other end side of a winding shaft (corresponding to a hub) is disclosed. .

However, since this means uses a tapered winding surface, winding failure tends to occur during winding, and productivity is poor. There is also a problem that the winding shaft becomes expensive.

The present invention has been made in view of such circumstances, and all the magnetic tapes cut from the original magnetic tape can be wound into the hub of the shipping cassette with good winding shape, and productivity and An object of the present invention is to provide a method for producing a pancake capable of remarkably improving the product yield.

[0014]

In order to achieve the above object, the present invention provides a magnetic tape fed from a magnetic tape supply source via a tape supply mechanism for guiding the magnetic tape around a hub. A method for producing pancakes wound around a hub, comprising: an axis of the hub, and an axis of a cylindrical surface provided at a tip portion of the tape supply mechanism.
There is provided a method for producing pancake, characterized in that a curved wrinkle is attached to a magnetic tape portion of the pancake by winding the magnetic tape so as to face each other at an intersection angle of ˜2 degrees.

According to the present invention, the magnetic tape is wound around the hub while being tensioned so as to have a curvature in the + direction by the cylindrical surface that is opposed to the hub axis at a predetermined angle. It is done. Therefore, regardless of whether the magnetic tape has a curvature in the + direction, has a curvature in the-direction, or has no curvature,
The film is forced to have a curvature in the + direction. Thereby, it can wind in the hub of a cassette for shipment with sufficient winding form, and can improve productivity and a product yield notably.

Here, a description will be given of a configuration in which the hub axis and the axis of the cylindrical surface provided at the tip of the tape supply mechanism are arranged to face each other at a predetermined angle. In the theory of transmission by rolling contact in mechanics, the two rotating bodies are (1) when the two axes are parallel (FIG. 8).
As shown in (a), mainly applied to the transmission of cylindrical wheels),
(2) When the axes of the two axes intersect (shown in FIG. 8 (b), mainly applied to the transmission of the conical wheel), (3) The axes of the two axes are neither parallel nor intersected The case (shown in FIG. 8 (c) and mainly applied to the transmission of a hyperbolic rotator).

That is, in the present invention, FIG.
The state in which the axes of the two axes at the time of transmission of the conical wheel as shown in Fig. 2 are applied to the transmission of the cylindrical wheel. FIG.
In the transmission of the cylindrical wheel with the two shaft axes parallel to each other as shown in (a), no tension is applied to the magnetic tape so as to bend, but as shown in FIG. If the axes of the two are in a state of crossing each other, a tension is applied so as to bend the magnetic tape.

Note that the crossing angle of the two axes at the time of transmission of the conical wheel shown in FIG. 9A is α + β.
The crossing angle of the two shaft centers at the time of transmission of the cylindrical wheel shown in (b) is θ.

In the present invention, if the crossing angle between the hub axis and the cylindrical surface can be set to an optimum value according to the curved shape of the magnetic tape, the effect of the present invention can be achieved more reliably. .

In the present invention, the cylindrical surface at the tip of the tape supply mechanism is preferably a touch roller rotatably supported by the tape supply mechanism. If the cylindrical surface of the tip of the tape supply mechanism is a touch roller,
This is because the touch roller is rotated according to the traveling of the magnetic tape, and the effect of the present invention can be achieved more reliably.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the pancake manufacturing method according to the present invention will now be described in detail with reference to the accompanying drawings.

The manufacturing apparatus applied to the pancake manufacturing method of the present invention is mainly a cutting apparatus 10 for cutting a wide strip-shaped magnetic tape roll wound in a roll shape into a plurality of narrow magnetic tapes. And a winding device 50 (corresponding to magnetic tape supply means) for winding the magnetic tape around the hub.

FIG. 1 is a schematic view showing an example of the cutting device 10, FIG. 2 is a side view of the cutting portion 14, and FIG. 3 is a schematic view showing an example of the winding device 50. As shown in FIG. 1, the cutting device 10 mainly includes a delivery unit 11, a cutting unit 14, and a winding unit 15. In addition, FIG.
In FIG. 2, the winding device 50 is not shown.

The hub 12 (core) of the delivery part 11 is
A roll of magnetic tape 20 is loaded. In the magnetic tape 20, a magnetic layer containing ferromagnetic fine particles is usually formed on a nonmagnetic support by a coating method, a vacuum deposition method, or the like, and the magnetic layer is subjected to orientation treatment, drying treatment, surface treatment, and the like. Manufactured by.

The cutting section 14 is a device for cutting the wide and strip-shaped magnetic tape 20 into a plurality of magnetic tapes 1, 1,... By a pair of upper and lower rotary blades 30, 32, as shown in FIG. In addition, a plurality of thin disk-shaped rotations that are cut by applying a shearing force to the magnetic tape raw material 20 between the plurality of rotating lower blades 30, 30. It consists of upper blades 32, 32.

The rotating lower blade 30 is fitted and fixed to the lower shaft 34 via a spacer 36, and the rotating upper blade 32 is fixed to an upper shaft 38 parallel to the lower shaft 34.
Are fitted and fixed, and the blade tip portions of the rotating upper blade 32 and the rotating lower blade 30 are arranged so as to overlap each other.
The rotating upper blade 32 is urged to the right in the axial direction of FIG. 2 by a spring (not shown), and is positioned in a state in which the cutting edge portion of the rotating upper blade 32 is in contact with the cutting edge portion of the rotating lower blade 30.

The upper shaft 38 and the lower shaft 34 are connected to motors 41 and 43 whose rotational speeds can be freely changed, respectively, and the peripheral speeds of the rotary upper blade 32 and the rotary lower blade 30 can be individually changed. Yes.

Between the delivery part 11 and the cutting part 14,
A plurality of guide rollers 22, 22,... Forming a conveyance path for the magnetic tape original fabric 20 and a ground suction drum 24 for regulating the conveyance speed of the magnetic tape original fabric 20 are provided. The ground suction drum 24 is connected to a motor (not shown) whose rotation speed can be freely changed, and the magnetic tape original fabric 20 is rotated by attracting the magnetic tape original fabric 20 to the peripheral surface of the ground suction drum 24. The conveyance speed of 20 is arbitrarily changed.

The rotational speed of the core 18 of the hub 2 in the winding section 15 is controlled based on the peripheral speed of the ground suction drum 24. The means for restricting the conveying speed of the magnetic tape original 20 is not limited to the ground suction drum 24, and a pinch roller that sandwiches and conveys the magnetic tape 20 can also be used.

A tension roller 28 is provided between the cutting portion 14 and each hub 2, and the tension in the transport direction of the magnetic tape original 20 at the time of cutting is arbitrarily adjusted.

As shown in FIG. 3, the winding device 50 corresponding to the tape supply mechanism includes an arm 5 which is a main body of the device.
2 and one end of the arm 52 so as to be freely rotatable.
Touch roller 54, which is a roller member that supplies magnetic tape 1 to the head, and a central portion of arm 52 so as to be rotatable.
A guide roller 56 that supplies the magnetic tape 1 to the touch roller 54, and a bearing portion 58 that is provided at the other end of the arm 52 and is rotatably fitted to a shaft 60 that is fixed to a housing (not shown). Is done.

3A is a front view of the winding device 50, and FIG. 3B is a side view. In FIG. 2B, the illustration of the magnetic tape 1 is omitted for convenience of explanation.

As shown in FIG. 3B, in the winding device 50, the axis C1 of the hub 2 and the axis C2 of the touch roller 54 as a roller member are opposed to each other with a predetermined crossing angle θ. It is arranged. In the figure, for easy understanding, the crossing angle θ is illustrated with emphasis from the fact. In order to make the two face each other with the crossing angle θ, the reverse relationship is established even if the axis of the hub 2 is set horizontally and the axis of the touch roller 54 is set with the crossing angle θ with respect to the horizontal. May be.

As described above, the hub 2 is rotationally driven in the direction indicated by the arrow in FIG.
The arm 52 is urged around the shaft 60 by an urging means (not shown) in the direction A in FIG. 3A, so that the touch roller 54 is pressed against the hub 2 via the magnetic tape 1. As the amount of the magnetic tape 1 wound around the hub 2 increases, the outer diameter increases. Accordingly, accordingly, the arm 52 moves in the direction B in FIG.

The touch roller 54 is not provided with an independent driving means, and the touch roller 54 rotates in the direction of the arrow as the magnetic tape 1 is conveyed.

Next, the operation of the pancake manufacturing apparatus constructed as described above will be described.

First, the roll-shaped magnetic tape 20 wound around the hub 12 of the delivery unit 11 is continuously drawn out from the hub 12 and conveyed to the cutting unit 14. And
The hub 2 is cut into a plurality of magnetic tapes 1 by the cutting part 14.
Is wound around the core 18. As a result, for example, the original magnetic tape 20 is cut into 100 to 500 pieces, and specified width dimensions (for example, 12.65 mm, 25.4 mm, 3.81).
mm) or the like.

FIG. 4 shows a cross-sectional shape of a pancake 3 (tape winding body in which a magnetic tape is wound around a hub) 3, (a) shows a shape during manufacture, and (b) shows a predetermined time after manufacture. The shape when aging is performed is shown.

If the crossing angle θ between the axis C1 of the hub 2 and the axis C2 of the touch roller 54 is in the range of 0.02 to 2 degrees, a result with a significant difference is obtained. Moreover, if the crossing angle θ is in the range of 0.1 to 1.0 degree, better results are obtained. Although this range varies somewhat depending on conditions such as the width and thickness of the magnetic tape 1, it has been confirmed that significant results can be obtained within the above range.

Here, the reason why the magnetic tape 1 with the curled wrinkles can be neatly wound into the cassette 4 by matching the bending direction of the magnetic tape 1 with the winding restriction direction will be described.

When the magnetic tape 1 having a static curved ridge having a curved ridge in only one direction in the + direction in FIG. 5A and the-direction in FIG. 5B is stretched in the longitudinal direction, the curved + direction is obtained. Or, the biasing force works only in one direction. Incidentally, the dynamic curve opposite to the static curve is a curve when the magnetic tape 1 is run, and refers to a wave having a shorter wavelength than the static curve.

On the other hand, when the magnetic tape 1 is wound around the hub 2 by the winding device 50, the winding of the magnetic tape 1 is regulated by positioning one end of the magnetic tape in the width direction in contact with the side surface of the hub 2. The

Therefore, if the magnetic tape 1 is wound so that the bending direction of the magnetic tape 1, that is, the direction of the urging force coincides with the winding restriction direction, the magnetic tape 1 is positioned on the surface of the cassette 4 or the side of the hub 2. Because you are involved, you can improve the winding appearance.

Conversely, if the magnetic tape 1 is wound so that the bending direction of the magnetic tape 1 is opposite to the winding restriction direction, the magnetic tape 1 is biased away from the surface of the cassette 4 or the side surface of the hub 2. Therefore, the magnetic tape 1 is difficult to be positioned on the cassette 4 surface or the hub 2 side surface,
The winding appearance gets worse.

The embodiment of the pancake manufacturing method according to the present invention has been described above. However, the present invention is not limited to the embodiment described above, and various aspects can be adopted.

For example, in this embodiment, the magnetic tape 20 is wound by the winding device 50 through the cutting portion 14 and is slit in advance to obtain the magnetic tape 1 having a predetermined width. It may be a mode of being sent out from the state of being. Further, the configuration of the winding device 50 is not limited to the present embodiment, and various configurations can be adopted.

In this embodiment, the touch roller 54 which is a roller member is used. However, a tip end shape which is a non-rotating cylindrical surface may be used. Further, this cylindrical shape is not strict, and may be, for example, a cross-section rectangular shape, a cross-sectional hyperbolic shape, or a cross-sectional elliptical shape. In this case, the heart passing through the focal point or the like corresponds to the axial center of the cylindrical surface.

In the present embodiment, the flange 2 is used as the hub 2, but a hub with a flange may be used.

Further, the following additional steps can be added to the present invention. That is, depending on the material of the magnetic tape 1, there are some which have a high longitudinal elastic modulus (Young's modulus) and are difficult to bend in a normal state. For such a magnetic tape 1, a process of performing a heat treatment immediately before being wound around the hub 2 is introduced. In this way, it is possible to easily attach a curved wrinkle.

[0050]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A pancake is manufactured by changing the intersecting angle θ between the axis C1 of the hub 2 and the axis C2 of the touch roller 54 using the pancake manufacturing apparatus having the above configuration.
Evaluation was performed after aging on a day (72 hours). The results are shown in Table 1. Aging condition is temperature: 25 °
C, relative humidity: 60%.

In this experiment, the crossing angle θ is −
A range of 1.0 to + 1.5 ° was employed. The magnetic tape 1 used has a tape width of 4 mm.

As evaluation items, the bending width D (unit: mm) with respect to the predetermined straight line length L (1 m) shown in FIG. 5, winding shape (◯: good, Δ: acceptable range, x: bad), edge damage Or not. The experimental results are shown in Table 1. Also,
The relationship between the crossing angle θ and the bending width D in Table 1 is shown in a graph in FIG.

[0053]

[Table 1]

According to the results shown in Table 1, the crossing angle θ
It was confirmed that good results were obtained in the range of 0 to + 0.3 °. When the crossing angle θ is −0.1 °, all evaluation items other than edge damage are defective.

[0055]

As described above, according to the present invention,
The magnetic tape is wound around the hub while being tensioned so as to have a curvature in the + direction due to the cylindrical surface arranged at a predetermined crossing angle with the hub axis. Therefore, regardless of whether the magnetic tape has a curvature in the + direction, has a curvature in the-direction, or does not have a curvature, the magnetic tape is forced to have a curvature in the + direction. Thereby, it can wind in a hub with sufficient winding form, and can improve a product yield notably.

[Brief description of the drawings]

FIG. 1 is a block diagram of a cutting apparatus in a pancake manufacturing apparatus according to the present invention.

FIG. 2 is a side view of the cutting part.

FIG. 3 is a block diagram of a winding device in the pancake manufacturing apparatus of the present invention.

Fig. 4 Cross section of pancake

FIG. 5 is an explanatory diagram for explaining the bending direction of a magnetic tape.

FIG. 6 is a cross-sectional view of a pancake stored in a case

7 is a graph showing the results of Example 1. FIG.

FIG. 8 is a conceptual diagram illustrating the theory of transmission by rolling contact

FIG. 9 is a conceptual diagram illustrating the intersection angle of rotating bodies.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Magnetic tape, 2 ... Hub, 3 ... Pancake (tape winding body which wound magnetic tape around hub), 4 ... Cassette, 1
0: Cutting device, 11: Sending unit, 14: Cutting unit, 15
... take-up unit, 20 ... magnetic tape original fabric, 50 ... take-up device (tape supply mechanism), 54 ... touch roller (roller member)

Claims (1)

[Claims] 1. A method for producing pancakes, in which a magnetic tape fed from a magnetic tape supply source is wound around the hub via a tape supply mechanism for guiding the magnetic tape around the hub. By winding the magnetic tape with the axial center and the axial center of the cylindrical surface provided at the tip of the tape supply mechanism crossing each other at an intersecting angle of 0.02 to 2 degrees, A method for producing a pancake, characterized in that a curved wrinkle is attached to a magnetic tape portion.