JPH033175A - Fixed magnetic disk storage device - Google Patents

Abstract

PURPOSE:To execute a tracking control even in the middle of reading and writing data, to eliminate a misread and, simultaneously, to improve a device performance by providing plural amplifiers corresponding to plural magnetic heads to read and write the data and differing the reading timings of respective servo signals. CONSTITUTION:A fixed magnetic disk storage device 1 is composed of disk 2-4, magnetic heads 9-14, recording surfaces 15-20, amplifiers A1 and A2 for read/write and read/write circuits C1 and C2. At such a time, respective recording surfaces 15-20 are divided into four sectors S, and the length of one sector to contain a servo pattern P is made into T. Since the number of recording surfaces of respective blocks B1 and B2 is three, respectively, the servo patterns P prepared by the servo signals for recording surfaces 15, 16, 17 and 18, 19, 20 are provided with the deflextion by the degree of T/3. Consequently, at the time of switching the heads 9, 10, 11 and 12, 13, 14 of respective read/write circuits C1 and C2 in synchronizing to the patterns P, the servo signals for positioning are obtained three times, respectively, per sector length T.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a fixed magnetic disk storage device, and particularly to a fixed magnetic disk storage device with improved tracking control performance when reading and writing data. It is.

[Prior Art] Conventional fixed magnetic disk storage devices employ control means such as index servo method, sector servo method, embedded servo method, etc. to position the magnetic head to the target cylinder and correct tracking errors. It has been known.

In the index servo type, a servo signal is written on the recording surface for a certain period in synchronization with an index signal detected once every rotation of the magnetic disk. When reading data, tracking is controlled by obtaining positioning information of the magnetic head once per rotation using the servo signal.

In addition, in the sector servo type, servo signals synchronized with each sector are written on the recording surface in the same number of sectors every rotation of the magnetic disk, and when reading data, the servo signals are detected for a certain period of time for each sector. This is used to control the tracking of the magnetic head.

On the other hand, in the embedded servo type, the magnetic film on the recording surface of the magnetic disk is divided into two layers, a surface layer and a deep layer, and a servo signal is written in advance to the deep layer, and data is written to the surface layer. When reading data, the output of the magnetic head is separated into data and servo signals by a filter to control the magnetic head.

Also, unlike the above-mentioned system, there is also known a system in which one side of the magnetic disk is used as a surface exclusively for servo signals.

[Problems to be Solved by the Invention] Among the fixed magnetic disk storage devices described above, those of the index servo type control the magnetic head by obtaining a servo signal once per rotation of the magnetic disk. The positioning time required to move the magnetic head to the top of the cylinder is long, making it difficult to speed up access. Further, since the servo signal is recorded only at a constant rotation angle during one rotation, the position of the magnetic head cannot be detected in any part other than the servo signal, and the magnetic head cannot be controlled against instantaneous tracking displacement. Therefore, it is difficult to keep the reading/writing error rate below a certain value, and this point is also the same for the sector servo system.

On the other hand, the embedded servo type does not have the above-mentioned drawbacks, but because it records separate signals in the surface and deep layers of the magnetic film, the magnetic film cannot be made thinner, making it difficult to increase the recording density. There is a limit.

Furthermore, when one side of the magnetic disk is dedicated to servo signals, the data storage capacity is reduced by the amount of the dedicated area, which is disadvantageous.

Therefore, a technical problem has arisen that must be solved in order to provide a fixed magnetic disk storage device that can accommodate higher recording density without reducing storage capacity and has improved tracking control performance. Therefore, the present invention aims to solve this problem.

[Means for Solving the Problems] The present invention was proposed to achieve the above object, and provides a fixed magnetic disk storage including a magnetic disk and a plurality of magnetic heads for reading and writing data to the magnetic disk. The device is a fixed magnetic disk storage device configured to electrically switch the plurality of magnetic heads to read and write data on the recording surface of a magnetic disk. The heads are separated and connected to the plurality of read/write amplifiers to form a plurality of read/write circuits, and the relative positions of the magnetic heads and servo signals of the plurality of read/write circuits are made different, respectively. It is an object of the present invention to provide a fixed magnetic disk storage device characterized in that while one read/write circuit is reading or writing data, another read/write circuit reads out the servo signal.

[Operations] This invention is provided with a plurality of magnetic heads, the plurality of magnetic heads are electrically switched to read and write data, and the plurality of magnetic heads are integrally interlocked on the recording surface. In a fixed magnetic disk storage device, a plurality of read/write amplifiers are provided, and the plurality of magnetic heads are connected to each other according to the number of read/write amplifiers, thereby forming a plurality of read/write circuits. Then, the recording positions of the servo patterns are shifted or the mounting positions of the magnetic heads are made different so that the servo signal readout timings of the plurality of read/write circuits are different, so that one While the read/write circuit is reading/writing data, another read/write circuit can simultaneously read the servo signal for positioning the magnetic head. Therefore, tracking can be controlled even while reading and writing data.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the accompanying drawings. For convenience of explanation, conventionally known technical matters will also be explained at the same time.

Figure 1 shows a fixed magnetic disk storage device (+), which is equipped with three magnetic disks (2), (3), and (4), and each magnetic disk (2) (3X4) is spaced at regular intervals. and is fitted onto the spindle (6) of the motor (5). A head carriage (7) is erected on the sides of the magnetic disks (2), (3), and (4), and is formed to be horizontally rotatable by means such as a step motor (not shown). Near the tip of the arm (7a) of the head carriage (η) head springs (8) (8)... are attached corresponding to the magnetic disks (2) (3) (4), and the head springs (8) (8) ... At the tip of the magnetic head (9) (10) (l 1) (L@ (1→(k
i) is permanently installed.

The magnetic head (9)(10)(l l)<O(1■(1
/I) are formed so as to sandwich the magnetic disks (2), (3), and (4) from above and below, respectively, by the biasing force of the head springs (8), (8), etc., and the head carriage (7)
By the rotation of the magnetic disks (2), (3), and (4), the magnetic disks move inward and outward on the recording surface (lE9 (If9 (■)), and read and write data or read servo signals. conduct.

Therefore, the magnetic head (9)B0)θ])(12(4(1)
4) into two read/write circuits (CI) (C2), and as shown in Figure 2, the upper magnetic head (9) (In) (l
1) and the lower magnetic head (12 (11)) are connected to separate read/write amplifiers (AI) (A2).

The read/write circuit (CI) (C2) is a switch circuit I21
), and the magnetic heads (9) (10) (l l), (2) (In (b)
The configuration is such that the desired data can be read or written or the servo signal can be read out by selecting and switching the desired data. For example, when the read/write circuit (C1) reads or writes data, the other read/write circuit (C2) reads the servo signal, and the magnetic head (9)
(10)(I 1), (1;1
l) is accurately positioned.

Next, a tracking control method will be explained according to FIGS. 3 and 4. Figure 3 (A), (B), and (C) show the recording surface (gull) constituting the block (Ell) corresponding to one of the two read/write circuits (CI) (C2). (!East) servo pattern (P) (P)...
Figure (B) is for convenience of explanation,
This is a perspective view from the top surface (lc9). In this embodiment, each recording surface θ!fl (lE9 (rt) (day (υ) is divided into four sectors (S) (S)... The length of one sector including the servo pattern (P) (P)... is (T).
It is. Since the number of recording surfaces of each block (Bl) (+12) is 3, the recording surface (G) (1 east (
rl), (1(+'!(a)) The servo patterns (P) (P)... formed by the servo signals every sector length (
T)/3.

Therefore, the magnetic head (
9) Qo) Q Q, (■ By switching 0 → (B) in synchronization with the servo pattern (P) (P)..., obtain servo signals for positioning three times per sector length (T). Although not shown, the recording surface (peak) constituting the other block (B2) is also formed in the same manner.

FIG. 4 is an explanatory diagram showing the relative positional relationship of the servo signal (PI) (P2)... on each recording surface (1'Jθf9 @ (I) axis. As mentioned above, the block (
Ill) ([12) Servo signal (PI) (P2
)... write timing is 1 sector length (T)!
The data is written in an offset manner so that the number of recording surfaces/number of blocks=6/2=3.

For example, when reading the data written in the sector (TI) of the block (Bl), the servo pattern (P?) provided on the recording surface (2) of the block (B2) is read out.
(P8) (P9) are sequentially read by switching the magnetic head (LD (L) ((b)).

Also, when reading data in sector (T2) of block (B2), read the data from the other block (81χ servo pattern (
P4) (P5) (Pfi) is read to control tracking of the magnetic head (Ilo) during data reading.

Therefore, the number of recording surfaces and the number of read/write circuits should not be limited to this embodiment. For example, if the number of recording surfaces is 10,
In a fixed magnetic disk storage device having two read/write circuits on the same side, the write timing of the servo signal may be offset so that one sector (T) length is divided into five.

(Number of recording surfaces/Number of read/write circuits = LO/2 = 5) Also, in this embodiment, a 4-sector configuration has been described, but it can be similarly applied to an 8-sector or 16-sector configuration. .

Although not shown in the drawings, as a method of creating a difference in the relative position of each magnetic head and the servo signal, two magnetic heads are connected to one read/write circuit, and the two magnetic heads are offset on the same recording surface. Alternatively, the two magnetic heads may be switched in synchronization with a servo signal to obtain positioning information twice per sector and control the magnetic head of the other read/write circuit.

Therefore, this invention can be modified in various ways without departing from the spirit of the invention, and it goes without saying that this invention extends to such modifications.

[Effects of the Invention] As described in detail in the above embodiment, the present invention provides a fixed magnetic disk storage device having a plurality of magnetic heads with a plurality of read/write amplifiers, and separates the magnetic heads to read/write the read/write amplifiers. are connected to each other to form multiple read/write circuits. Then, the servo signal arrangement or the mounting position of the magnetic head is set so that the relative position with respect to the servo signal magnetic head provided on the magnetic disk is different for each read/write circuit, and each of the read/write circuits The input timing of the output servo signals is different.

Therefore, even if the magnetic head of one read/write circuit is in a position other than the servo signal while reading/writing, the other read/write circuit can obtain positioning servo signals at regular time intervals. Therefore, the performance of fixed 6 fixed magnetic disk storage devices can be improved by improving tracking deviation control performance, improving read error rate, and speeding up target cylinder detection and access time. I can contribute.

[Brief explanation of drawings]

The figures show one embodiment of the present invention, in which Fig. 1 is a side view showing the main parts of a fixed magnetic disk storage device, Fig. 2 is a block diagram of the same circuit, and Fig. 3 (A) (B) ((:) 4 is an explanatory diagram showing the recording surface of a magnetic disk, and FIG. 4 is an explanatory diagram showing the arrangement state of servo signals on the recording surface of the magnetic disk.

Claims (1)

[Claims] A fixed magnetic disk storage device comprising a magnetic disk and a plurality of magnetic heads for reading and writing data to the magnetic disk, wherein the plurality of magnetic heads are electrically switched to read and write data to the recording surface of the magnetic disk. In a fixed magnetic disk storage device formed in The relative positions of the magnetic heads and the servo signals of the plurality of read/write circuits are made different, so that while data is being read or written by one read/write circuit, the servo signal is read by another read/write circuit. A fixed magnetic disk storage device characterized by: