JPH04241276A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To secure an area where the read/write of data can be performed on a part of the surface of a magnetic disk which is used for servo and to increase storage capacity as an entire magnetic disk device. CONSTITUTION:A magnetic head 12 for servo and a magnetic head 9d for data are set on one arm 8a, and a servo pattern is written in the partial area of the surface of the magnetic disk that the magnetic head 12 covers, then the remaining surface of the magnetic disk is used for data. The magnetic heads 9a-9g for data are controlled to interlock with the magnetic head 12 so as to perform the read/write of the data.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device, and particularly aims to improve the efficiency of its storage capacity.

0002

[Prior Art] Fig. 3 shows, for example, "Mitsubishi Electric Techniques VOL
,58・NO. 2/1984'', pages 32 to 36 (published by Ohmsha), is a schematic configuration diagram of a conventional magnetic disk device. In the figure, 1 is a host computer, 2 operates in response to instructions from the host computer 1,
A magnetic disk device includes an interface circuit 3, which will be described later, as a component, 3 is an interface circuit that mediates the transmission and reception of information with the host computer 1, and 4 demodulates when a read command is received from the host computer 1 via the interface circuit 3. When the read/write circuit 5 receives a seek command from the host computer 1 via the interface circuit 3, the read/write circuit 5 modulates the write command when it receives the write command. This is a servo circuit that moves and controls the position.

Reference numeral 6 is an enclosure for fixing and sealing circuits and components such as 9 to 13 to be described later, 7 is an actuator motor controlled by the servo circuit 5, and 8a to 8d are driven by the actuator motor 7. Arms 9a to 9c are fixed to arms 8b to 8d, and data magnetic heads 10a to 10c are for electromagnetically converting data supplied by the read/write circuit 4. Data magnetic disk surface for storing data, 11
12 is a servo magnetic disk surface on which a servo pattern for transmitting track information to the servo circuit 5 is written;
is fixed to the arm 8a like the data magnetic heads 9a to 9c, and is a servo magnetic head for reading the servo pattern on the servo magnetic disk surface 11; 13 is the data magnetic disk surface 10a to 10c and the servo magnetic disk This is a spindle motor for fixing or rotating the surface 11.

Next, the operation will be explained. That is, in a magnetic disk device configured as described above, information is written on a medium (magnetic disk). Referring to FIG. 3, a reading operation when information is written on the above-mentioned medium will be described. First, a seek command is transmitted from the host computer 1 to the magnetic disk device 2 to move the magnetic head 9 to a track position where desired information is written. Then, the interface circuit 3 inside the magnetic disk device 2 interprets the seek command and transmits "the moving direction and distance of the magnetic head 9" to the servo circuit 5 as data. The servo circuit 5 controls the actuator motor 7 based on the data to drive the arms 8a to 8d. The servo magnetic head 12 fixed to the arm 8a transmits the current position information written on the servo magnetic disk surface 11 to the servo circuit 5 for electromagnetic conversion, and controls by feeding back the information. , move the data magnetic heads 9a to 9c to the target track position.

[0005] When the seek command is completed, the host computer 1 transmits a read command for reading information. In response to the read command sent to the read/write circuit 4 via the interface circuit 3, the read/write circuit 4 selects one magnetic head from the data magnetic heads 9a to 9c and reads information from the selected magnetic head. The interface circuit 3 performs electromagnetic conversion and demodulation.
Send the information to the host computer 1 via
Finish the series of reading operations.

Regarding the write operation, similarly to the read operation described above, after the seek command is completed, the host computer 1 transmits a write command for writing information. According to the write command transmitted to the read/write circuit via the interface circuit 3, the read/write circuit 4 modulates information and
One magnetic head is selected from among them, current is applied to the selected magnetic head, information is written to a track on the magnetic disk, and a series of write operations are performed.

[0007]

[Problems to be Solved by the Invention] Since the conventional magnetic disk drive is configured as described above, there is a problem that one magnetic disk surface is occupied for servo control, reducing the storage capacity for data. there were.

[0008] This invention was made to solve the above-mentioned problems.
The purpose of this invention is to provide a magnetic disk device with a large storage capacity by making it possible to read and write data to both disks and disks.

[0009]

[Means for Solving the Problems] A magnetic disk device according to the present invention includes a plurality of magnetic heads provided on one arm, at least one of which is used for servo control, and the other magnetic heads are used for servo control. It is used for data, and the data magnetic head is controlled in conjunction with the servo magnetic head to read and write data.

0010

[Operation] The magnetic disk device according to the present invention has a plurality of heads on an arm, uses one magnetic head for servo control, controls other magnetic heads in conjunction with the servo magnetic head, and controls data. By reading and writing, part of the servo magnetic disk surface is used for data, increasing storage capacity.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is a host computer, 2 is a magnetic disk device, 3 is an interface circuit, 4 is a read/write circuit, 5 is a servo circuit, 6 is an enclosure,
7 is an actuator motor, 8a to 8d are arms, 9a
9g is a data magnetic head, 10a to 10c are data magnetic disk surfaces, 12 is a servo magnetic head, and 13 is a spindle motor. These circuits and components are the same as those of the conventional example.

In this embodiment, reference numeral 20 denotes a magnetic disk surface for both servo and data use on which a servo pattern is partially written, and a magnetic head 12 for servo use is provided on the corresponding arm 8a, and a magnetic head 12 for data use is provided on the corresponding arm 8a. The magnetic head 9d is also fixed. In addition, other arms 8b~
Two magnetic heads 9e to 9g for data are also fixed to each of the magnetic heads 8d.

FIG. 2 is a plan view of the magnetic disk of FIG. 1 viewed from above, and the magnetic disk surface 20 used for both servo and data has a servo surface 20a on which a servo pattern is written and a servo surface 20a on which data is read. Writable data surface 20b
is formed. The servo magnetic head 12 provided on the arm 8a is configured to cover the servo surface 20a, and the data magnetic head 9d is configured to cover the data surface 20b.

Next, the operation of the above embodiment will be explained. The series of steps in which the host computer 1 transmits a seek command and performs servo control is the same as in the conventional example. However, as shown in FIG. 2, two magnetic heads are attached to one arm, and when the servo magnetic head 12 moves from point A to point A1, the data magnetic head 9d
moves from point B to point B1 in conjunction with the servo magnetic head 12. Therefore, if the servo pattern is written on the track from point A to point A1 (servo surface 20a),
The area from point B to point B1 can be used as a data surface (zone) 20b.

Further, in FIG. 2, the arm 8a moves in an arc, but in this case, the storage density between tracks (Trac
k Per Inch = TPI), the outer periphery is dense and the inner periphery is coarse, but the storage density in the circumferential direction (Bit Pe
r Inch=BPI) is dense at the inner circumference and coarse at the outer circumference, so the correlation is maintained and a reduction in error rate can be expected.

[0016] In the above embodiment, one arm has two
Although the example in which two or more magnetic heads are arranged is shown, two or more magnetic heads may be arranged, and in this case, the data surface (zone) becomes larger and more effective. Furthermore, although the magnetic disk device in which the arm moves in an arc is used in FIG. 2, the actuator motor may be of a linear motor type. In this case, the magnetic heads may be arranged at regular intervals.

[0017]

As described above, according to the present invention, a plurality of magnetic heads are attached to one arm, at least one of which is used for servo, and the remaining data is transmitted in conjunction with this servo magnetic head. Since the magnetic head is controlled, a part of the magnetic disk surface, which was conventionally used for servo control, can be used for data, and a magnetic disk device with a large storage capacity can be obtained. Furthermore, since a plurality of magnetic heads are arranged on one arm, the moving distance (span) of one magnetic head is reduced, which also has the effect of speeding up the seek time.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing a magnetic disk device according to an embodiment of the present invention.

FIG. 2 is a plan configuration diagram of the magnetic disk of FIG. 1 viewed from above.

FIG. 3 is an overall configuration diagram showing a conventional magnetic disk device.

[Explanation of symbols]

1 Host computer 2 Magnetic disk drive 3 Interface circuit 4 Read/write circuit 5 Servo circuit 6 Enclosure 7 Actuator motors 8a to 8d Arms 9a to 9g Data magnetic heads 10a to c Data magnetic disk surface 13
Spindle motor 20 Servo/data magnetic disk surface 2
0a Servo surface 20b Data surface

Claims (1)

[Claims] 1. A plurality of magnetic disks, a rotary drive means for fixing and rotating the magnetic disks, and a plurality of rotary drive means located on the surface of each of the magnetic disks for reading or writing information stored on the magnetic disks. a magnetic head, an arm and driving means for fixing the magnetic head and causing the magnetic head to seek in the radial direction of the magnetic disk, and a servo pattern for position detection written on a part of the surface of the magnetic disk. In rare cases, a servo circuit that controls the position of the data magnetic head based on a signal detected from the servo magnetic head corresponding to the magnetic disk surface on which the servo pattern is written, and a current flowing through the magnetic head, In a magnetic disk device including a read/write circuit that records information on the magnetic disk and also processes a signal detected from the magnetic head and demodulates the original information, a plurality of magnetic heads are provided for one arm. at least one of them is used as a servo magnetic head, a servo pattern is written in a partial area of the magnetic disk surface corresponding to the movement of this servo magnetic head, and the remaining data magnetic heads are used as a servo magnetic head. A magnetic disk device that is controlled in conjunction with a magnetic head to read and write data.