JPS5837880A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To decrese the access time even with a large-size disk, by providing plural heads which are supported by the same head shifting mechanism and separated from each other in the radius direction of the disk. CONSTITUTION:The track designation information is supplied to a control circuit 5 from a computer, and the circuit 5 decides that the designated track belongs to an outer circumference track range Xa or an inner circumference track range Xb. After this decision, the circuit 5 selects the heads 4a and 4b that take charge of the above-mentioned track ranges respectively. After this selection, a head shifting mechanism 2 is driven to set the head 4a, for example, to make it opposite to the designated track positioned in the range Xa. In such way, the head 4a is set opposite to the designated track of the magnetic disk 1. Then the information is recorded and read by a command given from the computer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic disk device, and particularly to a magnetic disk 1IIIi in which the head movement distance is shortened to shorten the access time Yt.

A magnetic disk device rotates a disc-shaped magnetic disk at high speed, and uses a head that moves along the disk's surface in half of the disk to perform recording and playback on each track. It is often used as a data file because it is easy to read and reproduce information, and the access time is extremely short compared to magnetic tape devices.

In this case, conventionally commonly used magnetic disk drives have a head movement** on the outer periphery of the disk, and a head is provided at the tip of an arm extending from this head movement mechanism to the surface of the disk. The head is facing the surface of the disk, which is rotating at high speed, through a small gap, and the head moving mechanism is operated in response to a track designation from a computer, for example, to move the arm toward the disk. The head is moved in the radial direction to face the designated track.

However, in the magnetic disk device with the above configuration, the KWl is configured so that one head is moved to cover reading and writing of all tracks, but in extreme cases, the innermost track There may be times when it is necessary to move the vehicle from the truck to the outermost trunk. Therefore.

In a device configured in this way, the maximum access time corresponds to the maximum head movement time, which becomes extremely long as the disk diameter increases. is trending towards faster speeds,
Shorter access times are required for magnetic disks.

Therefore, it is an object of the present invention to provide a magnetic disk device that can shorten the access time from t to aa even when the size of the disk increases.

To achieve this purpose, the present invention provides a plurality of heads supported by the same head moving mechanism and spaced apart from each other in the radial direction of the disk, and selects the head closest to a designated track. At the same time, the head is moved so as to move the head toward a designated track (ms).Hereinafter, the magnetic disk device according to the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a magnetic disk device according to the present invention. In the figure, reference numeral 1 denotes a magnetic disk, which is rotated at high speed, for example, in the direction indicated by the arrow, by a disk motor (not shown). 2 is a moving head provided close to the outer periphery of the disk l! Il structure, 3m and 3b are the head movement @1112 to disk 1 at a predetermined distance from each other.
This is an upwardly ductile arm, and heads 4m and 4b serve at the tip of this arm 31°3b. In this case, arm 3 a e s b is provided at its tip and h
The heads 4M and 4b are aligned in the radial direction of the disk-1.
Its length is set so that it lines up with 1. Therefore, when the head moving groove 2 is driven, the arms 3M, 3b and the heads 4m, 4b move together in the radial direction of the disk l as indicated by the arrow B. 5 is a rule
This circuit confirms the current positions of the heads am and 4b, selects the heads 4m and 4b that are closest to the track designated by the track designation information, and controls the movement of the heads.

In the magnetic disk device configured in this way, the distance 1 between the heads 4m and 4b is set to the total track width T01/ of the disk 1.
is the entire track width! Outer track range X5t divided into two
-In charge.

The head 4b will be in charge of the inner track range xb.

Next, when track designation information is supplied from the computer to the control circuit 5, the control circuit 5 determines whether the designated track is in either the outer track range Xs or the inner track range xb. Once the range covered by the designated track is determined, the track range fI! Heads in charge of I 4 m', 4 b
t-Select.

Once the track range has been determined and the head selected, for example, the selected head 4at outer track range
Ranked in s! The head moving mechanism 2 is driven and moved so as to face the designated track. In this way, if the head 4a faces the designated track of the magnetic disk 10, then next time.

Records and reads information according to commands from the computer.

Therefore, when the two heads 4m and 4b are provided apart from each other by the total track width T, each head 4ae4b has an outer track range XJI and an inner track range that are the range of the total track width T04. They will each be in charge of NXb. As a result, when selecting a track included in the external station track range
It is sufficient to select the head and move it within the range of the total track width T using the head moving mechanism, and when selecting a track included in the tX inner circumferential track range Xb, it is sufficient to select the head 4bt-. Therefore, when selecting the innermost track from the outermost trunk, the head selection is switched from head 4a to head 4b, and the head moving mechanism 2t moves to move head 4atT4b to the center of rotation of disk 1. All you have to do is move it 4 to the side. Therefore, in this case, the maximum access time is t-1 heads compared to the conventional! Compared to If, the wings are reduced to about 4.

In the above embodiment, the case where two heads are provided apart from each other by the total track width has been described; however, the present invention is not limited to this. The access time is shorter than the previous one.

Further, the mutual distance between the heads is not specified, and the configuration may be such that the distance between each head is determined. However, in this case, the control circuit 5 controls the distance between each head. When track designation information is supplied, the head closest to the designated track is determined and selected, and the head is moved to make the selected head face the designated track. Drive control for the mechanism is required.

As described above, the magnetic disk device according to the present invention includes a plurality of heads spaced apart from each other by a predetermined distance in the radial direction of the magnetic disk, and each head is moved in the radial direction of the magnetic disk by a common head movement mechanism. A head tube having a similar amount to the designated track is selected, and this head is opposed to the designated track to write and read information.

Therefore, the moving range of the head is greatly reduced compared to the conventional one, and the access time can be shortened accordingly, which is an excellent effect.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a magnetic disk according to the present invention. 1...disc, 2...head movement! l! Groove, 3m
. 3b...Arm% 4g, 4b...Head, 5...t
llJ 111 circuit...

Claims (1)

[Claims] (1) A magnetic disk that is rotated at high speed by a motor. a head moving mechanism provided close to the disk;
a plurality of heads supported by the head moving mechanism so as to be movable in the radial direction of the magnetic disk and arranged in parallel and spaced apart from each other along the moving direction; and a plurality of heads designated in accordance with external track designation information. The head moving mechanism 'g:ll!' selects the head closest to the track and moves the selected head 'g:ll!' to face the designated track. 111 [I
A magnetic disk device characterized by comprising a control circuit that performs the following steps.