JP2003006802A - Magnetic recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high reproduced output and to enhance a data transfer rate and to provide a high reliable magnetic recording and reproducing device, by applying sufficient electric power stably to a rotating drum. SOLUTION: This device is a magnetic recording and reproducing device which performs recording and reproducing on a magnetic recording medium by winding the magnetic recording medium around a fixed drum 11 and a rotating drum 12 provided with a magnetic head 13, and by rotating a rotating drum 12. In the device, magnets 14 and coils 16 are located on a surface facing the rotating drum 12 of the fixed drum 11 and on a surface facing the fixed drum 11 of the rotating drum 12, respectively. A circuit connected to the coils 16 further is provided on the rotating drum 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus having a rotating drum and a fixed drum for recording / reproducing on / from a magnetic recording medium.

[0002]

2. Description of the Related Art In a conventional data storage system using a VCR (video cassette recorder) or a helical scan type tape, a winding head having a coil wound around a magnetic material is mainly used as a magnetic head attached to a rotating drum. Met.

[0003]

On the other hand, recently,
Magnetoresistive head using a magnetoresistive element (MR
Head) is being considered. This is intended to obtain a large reproduction output from a small reproducing magnetic head by using a magnetoresistive head (MR head) as a reproducing magnetic head among the magnetic heads attached to the rotary drum.

This MR head needs to flow a direct current through the magnetoresistive effect element in order to detect the reproduction output.
Therefore, it is necessary to supply a direct current to the MR head.

Conventionally, by using a rotary transformer,
While exchanging signals with the magnetic head attached to the rotary drum, power was supplied to the magnetic head. However, in the power supply method using this rotary transformer, it is difficult to supply sufficient electric power, and therefore it is difficult for the MR head to supply a direct current for detecting the reproduction output.

On the other hand, in the above-mentioned helical tape data storage system, in order to improve the transfer rate in the future, it is necessary to increase the number of magnetic heads mounted on the rotary drum. When the number of magnetic heads mounted on the rotary drum is increased in this way, it is desirable to carry out signal processing beforehand by mounting an IC for signal processing on the rotary drum. In this case, it is necessary to supply power to the signal processing IC mounted on the rotating drum.

In the helical tape data storage system, electric power is supplied to the rotary drum by a mechanical contact system using a slip ring to operate a magnetic head mounted on the rotary drum. However, this mechanical contact system is worried about contact wear and contact failure,
There is a problem with reliability (power stability).

Therefore, in order to improve the transfer rate in the future, a new method for supplying electric power to the rotary drum is needed.

In order to solve the above-mentioned problems, the present invention makes it possible to obtain a large reproduction output and improve the data transfer rate by stably supplying sufficient electric power to the rotary drum. And a highly reliable magnetic recording / reproducing apparatus.

[0010]

A magnetic recording / reproducing apparatus of the present invention has a fixed drum and a rotary drum on which a magnetic head is mounted, and a magnetic recording medium is wound around the fixed drum and the rotary drum to rotate. Recording / reproducing to / from a magnetic recording medium by rotating a drum,
A magnet is arranged on a surface of the fixed drum facing the rotating drum, a coil is arranged on a surface of the rotating drum facing the fixed drum, and a circuit connected to the coil is provided on the rotating drum.

According to the above-mentioned present invention, the magnet is arranged on the surface of the fixed drum facing the rotating drum, the coil is arranged on the surface of the rotating drum facing the fixed drum, and the circuit connected to the coil on the rotating drum. Since the magnetic field from the magnet is applied to the coil, an induced current can be generated in the coil, and the induced current can supply power to the rotating drum. It becomes possible to operate the connected circuit.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention has a fixed drum and a rotating drum on which a magnetic head is mounted. A magnetic recording medium is wound around the fixed drum and the rotating drum, and the rotating drum is rotated to perform magnetic recording. A magnetic recording / reproducing apparatus for recording / reproducing on / from a medium, wherein a magnet is arranged on a surface of a fixed drum facing the rotating drum, a coil is arranged on a surface of the rotating drum facing the fixed drum, and a coil is arranged on the rotating drum. The magnetic recording / reproducing apparatus is provided with a connected circuit.

According to the present invention, in the above magnetic recording / reproducing apparatus, the magnet of the fixed drum and the coil of the rotating drum are provided with a shield made of a magnetic material on the side opposite to the surface facing each other. And

FIG. 1 is a schematic configuration diagram of a main part (head drum part) of a magnetic recording / reproducing apparatus according to an embodiment of the present invention. This magnetic recording / reproducing apparatus uses a magnetic tape 20 as a magnetic recording medium to perform recording and reproduction on this magnetic tape.

A head drum portion 10 is composed of two cylindrical drums each having a central axis on the same line, that is, a lower fixed drum 11 and an upper rotary drum 12. The rotary drum 12 rotates around the central axis in the direction indicated by the arrow in the figure. Then, by winding the magnetic tape 20 around the fixed drum 11 and the rotating drum 12,
The rotation of the rotary drum 12 causes the magnetic tape 20 to run in the direction shown by the arrow.

The rotating drum 12 has a magnetic tape 2
A magnetic head 13 for recording / reproducing data for 0 is mounted. In FIG. 1, two magnetic heads 13 are mounted on a side surface near the fixed drum 11.

Further, FIG. 2 shows a developed view of the two drums 11 and 12 of the head drum portion 10. The present embodiment is characterized by the configuration of the surfaces of the fixed drum 11 and the rotary drum 12 of the head drum portion 10 that face each other.

A permanent magnet 14 is arranged on the surface of the fixed drum 11 facing the rotary drum 12. Then, the permanent magnet 14 is moved in a direction perpendicular to the main surface of the magnet (axial direction of the drum).
Further, the adjacent permanent magnets 14 are magnetized so that the N pole and the S pole are opposite (inverted) to each other. At this time, the permanent magnets 14 (14N, 14S) are continuously magnetized.

The coil 16 is arranged on the surface of the rotary drum 12 facing the fixed drum 11. With this coil 16, the permanent magnet 14 (14N, 14S) of the fixed drum 11
The magnetic flux from can be picked up.

With this structure, as the rotary drum 12 rotates, the magnetic flux from the permanent magnet 14 of the fixed drum 11 causes the coil 1 of the rotary drum 12 to rotate.
An induced current is generated at 6. An alternating current can be generated by this induced current to supply power to the rotary drum 12. That is, the fixed drum 11 and the rotating drum 12 constitute a generator.

The alternating current due to the induced current generated in the coil 16 is supplied to a rectifier circuit (not shown) connected to the coil 16 and converted into direct current. As a result, it can be used as a direct current for signal detection of the magnetoresistive head (MR head).

As shown in FIG. 2, if the magnets 14N and 14S of the fixed drum 11 are arranged so that there are as few gaps as possible, power can be efficiently generated.

FIG. 3 shows a plan view of the surface of the rotary drum 12 which faces the fixed drum 11. As shown in FIG.
The coil 16 provided on the rotary drum 12 includes a first coil 16A and a second coil 1 whose winding directions are opposite to each other.
6B and 6B are alternately arranged, and when the first coil 16A and the second coil 16B are applied with magnetic fields in opposite directions, the induced currents generated in the coil 16 flow in one direction without canceling each other. , Each coil 16 (16A, 16B) is connected (wired) to configure.

Further, in the present embodiment, as shown in FIGS. 2 and 4 (a sectional view of the head drum portion 10),
A shield 15 made of a soft magnetic material is arranged below the permanent magnet 14, that is, on the side opposite to the surface facing the rotating drum 12. Similarly, as shown in FIGS. 2 to 4, a shield 17 made of a soft magnetic material is arranged on the coil 16, that is, on the side opposite to the surface facing the fixed drum 11.

As a result, the permanent magnet 1 of the solid drum 11 is
The magnetic flux from 4 can be efficiently put into the coil 16 of the rotating drum 12. Also, these shields 15, 1
7 also serves as a magnetic shield that does not let out a strong magnetic field from the permanent magnet 14, so that the recording layer of the magnetic tape 20 can be prevented from being affected by the magnetic field of the permanent magnet 14.

Preferably, a recording / reproducing circuit such as an IC (not shown) is mounted in the rotary drum 12 and is connected to the coil 16 directly or through a rectifying circuit so that the recording / reproducing can be performed. It is configured to power the circuit. As a result, recording / reproducing can be performed on the magnetic tape 20 by controlling the circuit.

More preferably, in the rotary drum 12,
A circuit for performing signal processing, for example, an IC (not shown) is mounted,
By connecting to the coil 16 directly or through a rectifying circuit or the like, power is supplied to the circuit that performs the signal processing. This makes it possible to perform signal processing in advance inside the rotary drum 12 and pass the processed signal to the fixed drum 11 side.

Here, when the magnetic head 13 mounted on the rotary drum 12 has a multi-channel structure, for example, the schematic structure of the circuit in the rotary head 12 is shown in FIG. In FIG. 5, the power generated by the generator 21, that is, the coil 16 of the rotating drum 12 is rectified by the rectifier circuit 22,
Power supply voltage of amplifier 23 and 3-channel MR head M
It is used for the DC current flowing through R1, MR2 and MR3.

Then, in the amplifier 23, signals are respectively inputted from the 3-channel MR heads MR1, MR2 and MR3, and the 3-channel MR heads MR1 and MR are also provided.
It is configured so that the signals of MR2 and MR3 are collectively output. As a result, one set of rotary transformers for passing the output of the output amplifier 23 to the fixed drum 11 can be provided, and the rotary transformer can be miniaturized and simplified.

In FIG. 5, the signals of the three-channel MR heads MR1, MR2 and MR3 are combined into one by the amplifier 23, but the magnetic head 13 mounted on the rotary drum 12 is an inductive type magnetic head. Even if there is only a head, a large number of magnetic heads 1
It is possible to output the signals of 3 together. Also,
The number of channels is also not particularly limited.

According to the above-described present embodiment, it is possible to supply sufficient electric power to the rotary drum 12. As a result, it is possible to supply sufficient electric power to detect the magnetic field by the magnetoresistive head (MR head) that detects the magnetic field from the recording medium by passing a direct current. Therefore, an MR head can be used as the reproducing magnetic head 13 mounted on the rotary drum 12, and a large reproducing output can be obtained.

A recording / reproducing circuit (IC or the like) is mounted on the rotary drum 12, and sufficient electric power for operating this circuit can be supplied to perform recording / reproducing on the magnetic tape 20. .

Further, the magnetic head 13 is a rotary drum 12.
When a large number of magnetic heads 13 are mounted on the rotary drum 12, a signal processing circuit, for example, an IC is mounted on the rotary drum 12, and the signals of a large number of magnetic heads 13 are combined in this circuit and output in a channel number smaller than the number of heads. it can.

As a result, the rotary transformer can be miniaturized and simplified. Also, a large number of magnetic heads 1
3 signals can be output, and the transfer rate can be improved.

Since the permanent magnet 14 of the fixed drum 11 and the coil 16 of the rotary drum 12 are not in contact with each other, there are no problems such as wear and poor contact as in the mechanical contact method, and the rotary drum 12 is not caused. The electric power can be stably supplied to. Therefore, according to the present embodiment, a highly reliable magnetic recording / reproducing device can be configured.

Further, according to the present embodiment, the permanent magnet 14 of the fixed drum 11 and the coil 16 of the rotating drum 12 are used.
In addition, since the shields 15 and 17 made of a magnetic material are provided on the opposite sides of the surfaces facing each other,
The magnetic field from the permanent magnet 14 can be efficiently supplied to the coil 16, and the magnetic field from the permanent magnet 14 is prevented from going out of the drums 11 and 12 so that the magnetic layer of the magnetic tape 20 is not affected. Can be

In the above-mentioned embodiment, the permanent magnet is arranged on the fixed drum 11. However, by disposing the electromagnet using the coil on the fixed drum 11 and changing the winding method of the coil, the N pole is formed on the circumference. Even if the and the S poles are arranged alternately, it is possible to supply the electric power to the coil of the rotating drum in the same manner. When the magnet on the fixed drum side is an electromagnet, it is necessary to pass a current through this electromagnet, and therefore the power consumption of the head drum portion is slightly higher than that when a permanent magnet is used.

The head drum portion of the magnetic recording / reproducing apparatus of the present invention, which is composed of a fixed drum and a rotating drum, is a recording apparatus for recording only on a magnetic tape or a reproducing apparatus for reproducing only information recorded on the magnetic tape. The same can be applied to the device, and power can be similarly generated to supply electric power to the magnetic heads and circuits in the rotating drum. However, in these recording-only or reproduction-only devices, the number of magnetic heads mounted on the rotating drum is smaller than that of the magnetic recording / reproducing device, so that the rotating drum requires less electric power and the effect of power generation is reduced. Get smaller.

The present invention is not limited to the above-mentioned embodiments, and various other configurations can be adopted without departing from the gist of the present invention.

[0040]

According to the present invention described above, it is possible to supply sufficient electric power to the rotary drum through the coil provided on the rotary drum.

As a result, it becomes possible to use a magnetoresistive head (MR head) that detects a magnetic field from a recording medium by passing a direct current as the magnetic head mounted on the rotary drum, and a large reproduction output can be obtained. It will be possible to obtain.

Further, it becomes possible to mount a recording / reproducing circuit and a signal processing circuit in the rotary drum and supply sufficient electric power to operate these circuits. Therefore, it is possible to perform signal processing in advance in a signal processing circuit mounted in the rotary drum and output the signals of a large number of magnetic heads collectively, so that a rotary transformer for transmitting signals to the fixed drum side. Downsized
It is possible to simplify and improve the transfer rate.

Further, since the electric power can be supplied in a non-contact manner, the electric power can be stably supplied to the rotary drum, and a highly reliable magnetic recording / reproducing apparatus can be constructed.

In particular, in the case where the magnet of the fixed drum and the coil of the rotary drum are provided with shields made of magnetic material on the opposite sides of the surfaces facing each other, a magnetic field is efficiently applied to the coil of the rotary drum. It is possible to provide the magnetic field to the outside of the drum.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a main part (head drum part) of a magnetic recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is a developed view of two drums of the head drum portion of FIG.

FIG. 3 is a plan view of a surface of the rotary drum of FIG. 2 that faces a fixed drum.

FIG. 4 is a schematic sectional view of the head drum portion shown in FIGS. 1 and 2.

FIG. 5 is a diagram showing a schematic configuration of a circuit in the rotary head when the magnetic head has multiple channels.

[Explanation of reference numerals] 10 head drum section, 11 fixed drum, 12 rotating drum, 13 magnetic head, 14 permanent magnet, 15, 1
7 shield, 16 coils, 20 magnetic tape, 21
Generator, 22 rectifier circuit, 23 amplifier, MR1, M
R2, MR3 MR head

Claims (2)

[Claims] 1. A magnetic recording medium, comprising: a fixed drum; and a rotary drum on which a magnetic head is mounted. The magnetic recording medium is wound around the fixed drum and the rotary drum, and the rotary drum is rotated. A magnetic recording / reproducing apparatus for performing recording / reproducing with respect to, wherein a magnet is arranged on a surface of the fixed drum facing the rotating drum, and a coil is arranged on a surface of the rotating drum facing the fixed drum. A magnetic recording / reproducing apparatus in which a drum is provided with a circuit connected to the coil. 2. A shield made of a magnetic material is provided on each of the magnet of the fixed drum and the coil of the rotary drum on the side opposite to the surface facing the other drum. 1. The magnetic recording / reproducing apparatus according to 1.