JP2700340B2 - Magnetic storage device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic storage device, and more particularly, to a magnetic storage device having a rotating head having a small diameter.

[Prior Art] First, the background of the present invention will be described. FIG. 3 is a block diagram showing an example of the configuration of a conventional magnetic storage device.
This magnetic storage device uses a rotary head type digital audio tape recorder (hereinafter referred to as R-DAT) as an auxiliary storage device of the external computer 1. In the figure, when data from the external computer 1 is written on the magnetic tape 14, the data from the external computer 1 is given to the interface 2 via the line l1. The data of the line l1 is image information, audio information, or information on arithmetic processing in the external computer 1, and is transmitted for each information unit of two tracks on the magnetic tape 14 (hereinafter, this information unit is referred to as a frame). Is done. One frame includes, for example, 5120 bytes of data, and is divided by the external computer 1 for each frame and output.

FIG. 4 is a diagram showing the contents of one frame on the magnetic tape 14. As shown in FIG. 4, one frame of the magnetic tape 14 is divided into a plurality of areas. That is, for example, the individual data areas a to e and the data areas a to e
One frame is constituted by the parity areas Pa to Pe individually corresponding to. The 5120-byte data mentioned above is
It is divided and stored in data areas a to e each having a data amount of 1024 bytes. The parity areas Pa to Pe have, for example, 128 bytes of data, respectively, and individually correspond to the data of the data areas a to e. The data in the parity areas Pa to Pe is added in the interface 2 and used as an error correction code. R-DA
In T, as described later, the signal processing circuit 7
, The parity is added. However, higher reliability as an auxiliary storage device can be obtained by the structure of one frame shown in FIG.

Returning to FIG. 3, such data is output from the interface 2 to the memory 3 such as a random access memory via the line l2 and to the signal processing circuit 7 via the line l3.

FIG. 5 is a diagram showing a storage area in the memory 3. Referring to FIG. 5, memory 3 is divided into eight storage areas M0 to M7, and each storage area M0 to M7 stores data for one frame.

In the memory 3, data for one frame from the interface 2 is first stored in the storage area M0. At this time, the data in the storage areas M0 to M6 of the memory 3 are sequentially transmitted to the right storage areas M1 to M7, respectively. Further, the data in the storage area M7 is usually deleted. For example, as shown in FIG. 5A, when data of frame numbers N + 7 to N to be described later are stored in the storage areas M0 to M7, respectively, when the frame numbers N + 8 and N + 9 are sequentially input. The memory 3 changes from the store state shown in FIG. 5 (b) to the store state shown in FIG. 5 (c). Interface 2
Is performed in accordance with a control signal from a control circuit 4 constituted by a microcomputer, for example.

Parity is added to the data fetched from the interface 2 to the signal processing circuit 7 via the line 13 in the ordinary R-DAT. The data to which the parity has been added is output to the amplifier 8 via the line 14. Amplifier 8
The data signal amplified by the write head WB is supplied to the write head WA via the line l5 and to the write head WB via the line l6.
And written to the magnetic tape 14.
Switching of the amplifier 8 is controlled by a signal synchronized with the rotation of the rotating drum 9 from the synchronization circuit 13.

Such write heads WA and WB and read heads RA and RB described later are fixed to a cylindrical rotary drum 9.

FIG. 6 is a perspective view showing a configuration near the rotary drum 9. FIG. The rotating drum 9 is driven to rotate by the motor 6 around the axis in the direction indicated by the arrow 20. At this time, the servo circuit 5 controls the motor 6 by the control signal from the control circuit 4.
To control the rotation speed of the. The magnetic tape 14 is running in a direction indicated by an arrow 21 by a capstan motor (not shown) or the like. The magnetic tape 14 is in contact with the side surface of the rotating drum 9 at an angle A1.

The write heads WA and WB are provided on the diameter line on the side surface of the rotating drum 9. Similarly, the read heads RA and RB are also provided on one side of the rotary drum 9 on one diameter line. Write head WA and read head RA corresponding to write head WA
Is provided at an angle A2 in the circumferential direction of the rotating drum 9 and slightly shifted in the axial direction. Angle A2 is, for example, 90 °.

FIG. 7 is a view for showing how the write heads WA and WB run on the magnetic tape 14. FIG. Referring to FIG. 7, write heads WA and WB scan diagonally on magnetic tape 14 to form tracks A and B, respectively. The above-mentioned frame number is stored in a part of the subcode areas 16a and 16b. The data written on the magnetic tape 14 are read heads RA and RB individually corresponding to the write heads WA and WB.
Is read by The signals from the read heads RA and RB are supplied to the amplifier via the lines l7 and l8 shown in FIG.
Given to 10 respectively. At this time, the read head RA,
The RB reads data on tracks A and B formed by individually corresponding write heads WA and WB.

Returning to FIG. 3, the data signal amplified by the amplifier 10 is output to a synchronization circuit 11 via a line l9, and the synchronization circuit 11 synchronizes with the clock signal from the clock generation circuit 15. Note that the amplifier 10 is a synchronous circuit 13
The output of read heads RA and RB is switched and output to line l9 according to the synchronization signal from. The output of the synchronization circuit 11 is sent to a signal processing circuit 12 via a line 110, and the signal processing circuit 12 corrects data errors.
This error correction is performed based on the parity added by the signal processing circuit 7. At this time, signal processing such as error correction is performed by the synchronization circuit 13 in synchronization with signal processing such as parity load in the signal processing circuit 7.

The data output from the signal processing circuit 12 is a line l12
To the interface 2 described above. Normally, in the interface 2, data is stored in the memory 3 via the line l2, and thereafter, the data is read from the memory 3 and output to the external computer 1.

FIG. 8 (a) is a diagram showing an arrangement of a writing head and a reading head with respect to a rotating drum having a normal diameter in a conventional R-DAT. For the rotating drum 90 having such a normal diameter, the winding angle A1 of the magnetic tape is 90 °. In this case, as shown in FIG. 8 (b), writing and reading of two pairs of heads were performed by one rotation of the drum.

[Problems to be Solved by the Invention] For example, assuming that the winding angle of the magnetic tape around a rotating drum having a normal diameter of 30 mm is 90 °, the winding angle A1 of the magnetic tape around the rotating drum 90 having a diameter of φmm is , A1 = 90 ゜ × (30 / φ). For example, when φ = 10 mm, A1 = 270 °.

FIG. 9 is a diagram for explaining the read operation of the write head and the read head of the rotating drum having a drum diameter smaller than 30 mm. When the winding angle of the magnetic tape around the drum 90 becomes 90 ° or more, when writing and reading are performed by one rotation of the rotating drum 90 using four heads,
There is a problem in that a partial overlap occurs between the write time and the read time, and crosstalk occurs as shown in FIG. As a result, it has been difficult to realize a magnetic storage device having a small rotating drum having a small diameter.

It is therefore an object of the present invention to provide a magnetic storage device having a small, compact rotating drum.

Means for Solving the Problems According to the present invention, a pair of recording heads and a reading head are provided on the circumference, and data recorded by the pair of recording heads by being rotated in a predetermined direction is recorded. A magnetic storage device including a rotary drum for reading by a pair of read heads has a diameter of the rotary drum of about 10 mm, and a magnetic tape for storing and reading data is provided on the circumference of the rotary drum.
Wound at an angle of 270 °, the first and second recording heads and the reading head are arranged on the drum in the order of the first recording head, the first reading head, the second recording head, and the second reading head. Are separated from each other by 90 °,
Data recorded by the first and second recording heads are read by the first and second reading heads, respectively, thereby defining one cycle of recording and reading,
When the rotating drum is rotated in a predetermined direction, the first and second recording heads and the first and second reading heads are arranged so that the first recording head, the second reading head, the second recording head, One read head comes into contact with the tape in the order, and the rotating drum is rotated three times, whereby one cycle is achieved.

[Operation] In the magnetic storage device according to the present invention, the diameter of the rotating drum is about 10 mm, the magnetic tape is wound around the head at an angle of 270 °, and the positions of the recording head and the reading head on the drum circumference are as described above. It is specified as follows. Since one cycle of recording and reading by the magnetic head is performed by three rotations of the rotating drum, no crosstalk occurs.

FIG. 1 is a diagram showing the positional relationship between a recording head and a reading head in a rotating drum of a magnetic storage device according to the present invention, and the time from recording to reading by each head in that case. FIG. 1 (a) shows the positions on the circumference of the four heads, and FIG. 1 (b) shows the time at which each head contacts the tape based on the rotation angle of the rotating drum. . The rotating drum is rotated in the direction indicated by the arrow in FIG.

Referring to FIG. 1 (a), a pair of recording heads WA and WB are circumferentially arranged at the center of the drum on a rotating drum of a magnetic storage device to which the present invention is applied. A first read head RA for reading data of the first print head is provided at a position rotated by about 90 ° in the rotation direction of the rotary drum from one of the print heads WA. A second read head RB for reading the second data is provided at an appropriate position. In the embodiment shown in FIG. 1, the tape is wound around the rotary drum by 270 °. Referring to FIG. 1B, the first recording head WA
Assuming that the tape is wound from the position 270 ° to the position 270 ° in the direction of rotation of the drum, the time during which each head contacts the tape is represented by the rotation angle of the drum as shown in FIG. 1B. In the figure, the part shown by a solid line is a time zone in which each head is operated, and the part shown by a dotted line simply shows a time zone in which each head contacts the tape. Referring to FIG. 1B, after the first recording head WA rotates by 270 °, the first reading head RA comes into contact with the tape. Next, data is written by the second recording head WB, and data is read by the read head RB.

FIG. 2 is a diagram showing the relationship between the writing and reading operations of FIG. 1 and the rotation of the drum. Referring to FIG. 2, recording by two pairs of heads by three rotations of the drum,
One cycle of reading is performed.

[Effects of the Invention] As described above, according to the present invention, the diameter of a tape having a pair of recording and reading heads is 10 mm and the tape wrap angle is 27 mm.
In the rotating drum type magnetic storage device of 0 °, the arrangement of each head is such that the first recording head and the first recording head are arranged in the rotation direction of the drum.
Since one cycle of recording and reading is performed by three rotations of the drum in the order of the reading head, the second recording head, and the second reading head, crosstalk occurs even when the drum diameter is small and the tape winding angle is large. Absent.

As a result, a DAT with a small rotating drum with a small diameter
There is an effect that a magnetic storage device as described above can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram showing the arrangement of each magnetic head on a rotating drum applied to the magnetic storage device according to the present invention, and the relationship between the recording / reading timing of the head and the rotation angle of the head. FIG. 3 is a block diagram of a magnetic storage device for explaining the background of the present invention, FIG. 4 is a diagram showing the contents of one frame on a magnetic tape, and FIG. FIG. 6 is a diagram showing a storage area in the memory shown in FIG. 3, FIG. 6 is a perspective view showing a configuration near a rotary drum, and FIG. 7 is a diagram showing how a write head moves on a magnetic tape. FIG. 8 is a view showing the arrangement of a magnetic head on a rotating drum in a conventional magnetic storage device, and FIG. 9 is a diagram showing writing and writing of each head in the conventional magnetic storage device. For explaining the read operation It is. WA and WB are recording heads, RA and RB are read heads, 9 and 90 are rotating drums, and 14 is a magnetic tape. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

(57) [Claims] 1. A pair of recording heads and a pair of reading heads are provided on a circumference, and data recorded by the pair of recording heads is rotated by rotating in a predetermined direction.
A magnetic storage device including a rotating drum for reading by a pair of reading heads, wherein the diameter of the rotating drum is about 10 mm, and a magnetic tape for storing and reading the data on a circumference of the rotating drum. Is wound at an angle of about 270 °, and the first and second recording heads and reading heads are
A first recording head, a first reading head, a second recording head, and a second reading head, which are provided in this order on the rotating drum at an interval of 90 ° from each other; The data recorded by the recording head is read by the first and second reading heads, respectively, thereby defining one cycle of recording and reading, the first and second recording heads and the first and second recording heads. The read head includes the first recording head and the second recording head when the rotary drum is rotated in the predetermined direction.
Read head, the second recording head, and the first read head come into contact with the tape in this order, and the rotating drum
A magnetic storage device wherein one cycle is achieved by being rotated.