JPH117674A - Rotary magnetic recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a contact state good over a whole contact range of a rotary magnetic recording section with a magnetic recording medium by providing a rotary member for adjusting a contact state of the rotary magnetic recording section with the magnetic recording medium at either side of an inlet side and an outlet side of the magnetic recording medium of the rotary magnetic recording section. SOLUTION: A rotary magnetic head device 10 is provided with fixed drum and a rotary drum 12 constituting a rotary magnetic recording section, a inlet side cylindrical pole 14 of a motor and a rotary member, an outlet side cylindrical pole 15, and the like. The inlet side cylindrical pole 14 and the outlet side cylindrical pole 15 have columnar planes made of a metal material such as aluminum and brass, or a resin material and having the same width as that of a magnetic tape or wider and a rotation driving section rotating itself is incorporated in it. The rotation driving section is arranged near a tape inlet side T1 and a tape outlet side TO of the rotary drum 12. A magnetic tape is brought into contact with and slid to the rotary drum 12 and the fixed drum through a supply reel 21, an inlet side roller 22, and the inlet side cylindrical pole 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating magnetic recording apparatus for exchanging information signals with a magnetic recording medium.

[0002]

2. Description of the Related Art A rotary magnetic head device, which is a rotary magnetic recording device, is provided in an information recording / reproducing apparatus such as a video tape recorder (VTR), a data streamer, and a digital audio system. A rotating drum constituting a rotating magnetic recording unit of the rotating magnetic head device includes:
Many magnetic head devices for recording, reproduction, erasing, etc. are mounted, and information signals are exchanged by contact sliding between a magnetic tape, which is a magnetic recording medium wound around a rotating drum, and a magnetic head of these magnetic head devices. .

Here, when the rotating drum is rotated in a state where the magnetic tape with a predetermined tension is wound around the rotating drum (tape wrap state), air is drawn into the gap between the rotating drum and the magnetic tape. Then, the magnetic tape floats stably from the surface of the rotating drum in a state where the pressure of the air and the pressing force by the tension are balanced. That is, a gap called an air film occurs in the tape wrap range.

The air film has a stable thickness at the center of the tape wrap area. However, as shown in FIG. 4, at the tape inlet side TI of the rotary drum D, the air pressure rises due to the suction of air accompanying the rotation of the rotary drum D, so that the air film becomes unstable,
In the direction in which the magnetic tape T moves away from the rotary drum D, the contact state between the magnetic tape T and the rotary drum D (hereinafter referred to as "hit") deteriorates. Further, at the tape outlet side TO of the rotary drum D, the pressure of the air decreases due to the discharge of the air accompanying the rotation of the rotary drum D, so that the air film becomes unstable and the magnetic tape T is drawn into the rotary drum D. In the same direction, the hit gets worse.

In order to verify the above, the cross section of the magnetic tape T shown in FIG.
When the behavior of the magnetic tape T is simulated using the tape wrap angle shown as a parameter, the air pressure becomes as shown in FIG. 6A and the thickness of the air film becomes as shown in FIG. The tape wrap angle is
Rotary drum D at tape entrance TI of rotary drum D
The contact starting point between the magnetic tape T and the magnetic tape T is set to 0 degree.

As apparent from these results, the thickness of the air film near the tape inlet side TI of the rotary drum D increases with an increase in the air pressure. In the vicinity of the outlet side TO, the thickness of the air film decreases with a decrease in the air pressure. Therefore, in order to reduce the thickness of the air film particularly at the tape entrance side TI, in the conventional rotary magnetic head device, an air groove for releasing air is provided on the outer peripheral portion of the rotary drum D, or the air groove is applied to the magnetic tape T. By increasing the tension, the contact of the rotary drum D at the tape inlet side TI is improved.

[0007]

The above-mentioned rotary drum D
In the rotary magnetic head device in which the air groove is arranged on the outer peripheral portion of the tape, the air groove rotates, so that the thickness of the air film decreases over the entire tape wrap range. Therefore, the tape entrance side T of the rotating drum D
Although the hit at I is good, the hit at the center of the rotary drum D and at the tape outlet side TO of the rotary drum D deteriorates,
There is a problem that the magnetic tape T may be damaged. Further, in a rotating magnetic head device in which the tension applied to the magnetic tape T is increased, the magnetic tape T is strongly pressed against the rotating drum D, so that the magnetic tape T may be damaged or the life of the magnetic head may be shortened. There was a problem.

The present invention has been made in view of the above circumstances, and provides a rotary magnetic recording apparatus capable of improving the contact state over the entire contact range between a magnetic recording medium and a rotary magnetic recording section. Aim.

[0009]

According to the present invention, there is provided a rotating magnetic recording apparatus having a rotating magnetic recording section for exchanging information signals by sliding in contact with a magnetic recording medium. This is achieved by providing a rotating member for adjusting a contact state between the rotating magnetic recording unit and the magnetic recording medium on at least one of the magnetic recording medium entrance side and the magnetic recording medium exit side of the unit. .

[0010] According to the above configuration, since the rotating member capable of adjusting the contact state is disposed at a position where the contact state between the rotating magnetic recording unit and the magnetic recording medium is likely to be deteriorated, the rotation of the magnetic recording medium and the magnetic recording medium are prevented. The contact state can be improved over the entire contact range with the magnetic recording section.

[0011]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The embodiment described below is a preferred specific example of the present invention,
Although various technically preferable limits are given, the scope of the present invention is not limited to these embodiments unless otherwise specified in the following description.

FIG. 1 is a plan view showing a peripheral portion of an example of a rotary magnetic head device which is an embodiment of the rotary magnetic recording device of the present invention, and FIG. 2 is a perspective view showing the rotary magnetic head device. . The rotating magnetic head device 10 includes a stationary drum 11 and a rotating drum 12 that constitute a rotating magnetic recording unit.
And a motor 13 and a rotary member for adjusting the contact state between the rotary magnetic recording unit and the magnetic recording medium.

The fixed drum 11 is provided with a lead guide portion 11a for guiding a magnetic tape T as a magnetic recording medium obliquely from a tape entrance side TI to a tape exit side TO along a tape running direction E. Have been. The rotating drum 12 is provided with reproducing heads RHa and RHb having a phase difference of 180 degrees and recording heads WHa and WHb, and is rotated in the direction of arrow R with respect to the fixed drum 11 by the operation of the motor 13. I do.

Each of the inlet-side cylindrical pole 14 and the outlet-side cylindrical pole 15 has a cylindrical surface of at least the width of the magnetic tape T made of a metal material such as aluminum or brass or a resin material. Are provided in the vicinity of the tape inlet side TI and the tape outlet side TO side of the rotary drum 12 (fixed drum 11). In this embodiment, the inlet-side cylindrical pole 14 and the outlet-side cylindrical pole 15 are provided, but any one of them may be provided. In addition, although the rotation drive units of the inlet-side cylindrical pole 14 and the outlet-side cylindrical pole 15 are built in, they may be provided outside.

In such a configuration, the magnetic tape T
The rotary drum 12 and the fixed drum 11 are supplied from the supply reel 21 through the inlet-side roller 22 and the inlet-side cylindrical pole 14.
, And is wound on a take-up reel 24 via an outlet-side cylindrical pole 15 and an outlet-side roller 23. The outlet roller 23 is provided with a capstan 23a that is rotated by a capstan motor M.

Here, as described in the prior art, at the tape inlet side TI of the rotary drum 12, the pressure of the air rises due to the suction of the air accompanying the rotation of the rotary drum 12, and the magnetic tape T is separated from the rotary drum 12. Try to leave. However, the magnetic tape T is formed on the entrance side cylindrical pole 14.
As a result, the air film has a stable thickness. Further, at the tape outlet side TO of the rotary drum 12, the pressure of the air decreases due to the discharge of the air accompanying the rotation of the rotary drum 12, and the magnetic tape T tends to be drawn into the rotary drum 12. However,
Since the magnetic tape T is separated by the outlet-side cylindrical pole 15, the air film has a stable thickness.

In order to verify the above, the magnetic tape T near the tape inlet side TI of the conventional rotary drum D is set as shown in FIG. When the behavior of the magnetic tape T near the tape entrance side TI of the rotary drum 12 of this embodiment is simulated, the thickness of the air film is as shown in FIG. The white circles in the figure show the results of the conventional rotary magnetic head device, and the black circles in the figure show the results of the rotary magnetic head device 10 of this embodiment.

As is clear from these results, the thickness of the air film at a tape wrap angle of 0 ° at which the magnetic tape T originally starts to wind around the rotating drums D and 12 is as follows.
In contrast to the conventional rotary magnetic head device of about 13 μm, the rotary magnetic head device 10 of this embodiment has a thickness of about 10 μm.
μm. In the conventional rotary magnetic head device, the tape wrap angle at which the thickness of the air film starts to stabilize is about 10 degrees, whereas in the rotary magnetic head device 10 of this embodiment, the thickness of the air film is stable. The tape wrap angle at which it starts to move has been advanced to about 3 degrees.

Accordingly, the provision of the inlet-side cylindrical pole 14 makes it possible to improve the contact between the rotary drum 12 and the tape inlet side TI. In addition, a phenomenon opposite to the above-described phenomenon occurs at the tape outlet side TO of the rotary drum 12, so that the contact at the tape outlet side TO of the rotary drum 12 can be improved.

The amount of magnetic tape T pulled in by the inlet-side cylindrical pole 14 and the amount of magnetic tape T pulled out by the outlet-side cylindrical pole 15 are determined by the relative speed between the cylindrical poles 14 and 15 and the magnetic tape T, that is, each cylinder. Paul 14, 15
Can be controlled by changing the peripheral speed at the outer periphery of the motor. For example, relative to the relative speed between the rotating drum 12 and the magnetic tape T, that is, the peripheral speed at the outer periphery of the rotating drum 12,
By setting the peripheral speed on the outer periphery of each of the cylindrical poles 14 and 15 to at least twice or more, an optimum contact can be obtained. In this case, a feedback servo function of the peripheral speed on the outer periphery of the rotary drum 12 and the peripheral speed on the outer periphery of each of the cylindrical poles 14 and 15 is provided.

According to the above configuration, the rotary drum 1
Even if an air groove is provided on the outer peripheral portion of the magnetic tape 2, damage to the magnetic tape T caused by an air breakage phenomenon can be improved. Further, since the hit can be improved without increasing the tension applied to the magnetic tape T, the life of the magnetic head can be extended. Further, the hit can be improved according to the situation of each of the rotating drums 12 or the set of the rotating magnetic head device 10. Since the variation of the tape path in the set state of the rotary magnetic head device 10 can be absorbed, the accuracy of each of the rotary drum 12 or each set of the rotary magnetic head device 10 can be relaxed, and the manufacturing can be simplified. Cost can be reduced.

[0022]

As described above, according to the present invention, the contact state can be improved over the entire contact area between the magnetic recording medium and the rotating magnetic recording section.

[Brief description of the drawings]

FIG. 1 is a plan view showing a peripheral portion of an example of a rotary magnetic head device which is an embodiment of a rotary magnetic recording device of the present invention.

FIG. 2 is a perspective view of the rotary magnetic head device of FIG. 1;

FIG. 3 is a diagram when a behavior of a magnetic tape in the rotating magnetic head device of FIG. 1 and the rotating magnetic head device of FIG. 5 is simulated;

FIG. 4 is a diagram showing a problem of behavior of a magnetic tape in a conventional rotary magnetic head device.

FIG. 5 is a schematic view showing an example of a conventional rotary magnetic head device.

FIG. 6 is a diagram when a behavior of a magnetic tape in the rotary magnetic head device of FIG. 5 is simulated;

[Explanation of symbols]

Reference numeral 10: rotating magnetic head device, 11: fixed drum, 12: rotating drum, 13: motor, 14.
..Inlet-side cylindrical pole, 15 ... Outlet-side cylindrical pole,
21 ... supply reel, 22 ... entrance side roller, 23
... Exit roller, 24 ... Take-up reel, T ...
Magnetic tape, TI: Tape entry side, TO: Tape exit side

Claims (3)

[Claims] 1. A rotary magnetic recording device having a rotary magnetic recording unit for exchanging information signals by sliding in contact with a magnetic recording medium, wherein the rotary magnetic recording unit has a magnetic recording medium entrance side and a magnetic recording medium exit side. A rotating member for adjusting a contact state between the rotating magnetic recording section and the magnetic recording medium on at least one side of the rotating magnetic recording apparatus. 2. The rotating magnetic recording apparatus according to claim 1, wherein the rotating member has a cylindrical surface at least as large as the width of the magnetic recording medium. 3. The rotating magnetic recording apparatus according to claim 1, wherein said rotating member has a built-in rotation driving unit for rotating itself.