JP2966206B2 - Hard disk drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hard disk drive, and more particularly to a disk drive capable of simultaneously servo-writing a disk through a plurality of heads and reducing the influence of noise generated by a disk rotation motor. Hard disk drive

[0002]

2. Description of the Related Art Conventionally, in a hard disk drive,
When there are one or more disks (magnetic disks) and at least two or more heads arranged corresponding to the disks, for example, when individual heads are respectively arranged on both surfaces of one disk When the magnetic recording surfaces on both sides of the disk (hereinafter simply referred to as recording surfaces) are servo-written via the head, that is, when the servo information is magnetically recorded, one built-in read / write
According to the operation of the write integrated circuit, first, one of the heads is selected to perform servo writing on the recording surface 0, and after that, the other head is switched to perform servo writing on the recording surface 1, and so on. Servo write processing was performed in the order of recording surfaces.

[0003] The servo write processing in the recording surface order is the same even when the number of disks of the hard disk device increases and the number of heads increases accordingly. In the case where a total of four heads are arranged on both sides of the head, the operation of the one read / write integrated circuit firstly performs the servo writing of the recording surface 0 by the 0th head, and then, First
The servo write of the recording surface 1 by the head No. 2, the servo write of the recording surface 2 by the head No. 2, and finally,
The servo writing on the recording surface 3 by the third head is sequentially performed.

FIG. 5 is a schematic configuration diagram showing a head drive portion of the conventional hard disk drive.

In FIG. 5, reference numeral 50 denotes a 0th head, 5
1 is a first head, 52 is a second head, 53 is a third head, 54 is one read / write integrated circuit (R / W · IC) built in the hard disk drive,
Reference numeral 55 denotes a servo track writer (STW) outside the hard disk device.

Then, a 0th head 50, a 1st head 51, a 2nd head 52, and a 3rd head 53
Are connected to a read / write integrated circuit 54, respectively, and the read / write integrated circuit 54 is connected to a servo track writer (STW) 55.

[0007] The head driving portion of the hard disk drive having the above-described configuration operates as follows.

[0008] When a servo command signal for performing servo writing on the recording surface is supplied from the servo track writer (STW) 55 to the read / write integrated circuit 54, the read / write integrated circuit 54 first starts the 0th head. 50
And selects the recording surface 0 of a disk (not shown) facing the head 50 via the 0th head 50.
Execute the servo write. When the servo write is completed, the read / write integrated circuit 54 next switches and selects the first head 51, and records a disk (not shown) facing the head 51 via the first head 51. Execute the servo write on the surface 1. Hereinafter, similarly,
The servo write of the recording surface 2 of the disk (not shown) facing the head 52 is executed via the second head 52, and finally, the head 5 is written via the third head 53.
The servo write of the recording surface 3 of the disk (not shown) opposite to the disk 3 is executed.

In addition, this type of hard disk drive requires a power supply line for supplying drive power from an input / output terminal to a disk rotation motor for rotating the disk. Is supplied by using a flexible printed wiring board in which a plurality of power supply lines are formed in the form of a flexible printed wiring.

[0010]

However, when a plurality of heads are used, the head driving portion of the conventional hard disk drive uses one read / write integrated circuit to select the plurality of heads. Are sequentially performed, and the recording surface of the disk corresponding to the selected head is servo-written. That is, since the servo writing is performed in the recording surface order, the servo writing of all the recording surfaces is performed. There is a problem that the time, that is, the machine time becomes longer.

Further, if servo writing is performed separately on each recording surface as in a head drive portion of a conventional hard disk drive, the disk rotates only while the servo writing is being performed. There is also a problem that the head is wobble in the output.

Further, in the conventional hard disk drive, when the flexible printed wiring board is coupled to the disk rotating motor, the direction of coupling of the flexible printed wiring board to the disk rotating motor is the same as the coupling direction of the flexible printed wiring board. In this case, a direction suitable for the operation is selected only, and the relationship between the coupling direction of the flexible printed wiring board and the movable range of the head is not taken into consideration. Is generated by the head via the flexible printed circuit board, and is superimposed on data (signal) during recording, and is also superimposed on the read data when reading data recorded on the disk. Output, and the noise is the ID disk There is a problem that is particularly greatly affected by the inner circumferential side.

An object of the present invention is to eliminate the above-mentioned various problems. One object of the present invention is to reduce the time for performing servo writing on all recording surfaces, that is, so-called machine time, and to reduce the disk rotation time. An object of the present invention is to provide a hard disk drive in which the influence of fluctuations and head wobble is reduced.

Another object of the present invention is to provide a hard disk drive which reduces noise generated from a disk rotating motor from being guided to a head via a flexible printed wiring board.

[0015]

According to one aspect of the present invention, there is provided a disk drive comprising: at least two disks; at least four heads disposed on both sides of the at least two disks; One read / write integrated circuit, and a servo write circuit provided with one less write circuit than the total number of heads, and one read / write integrated circuit is coupled to one head. Each write circuit is individually coupled to the corresponding remaining head, and one read / write integrated circuit and each write circuit are driven by a signal supplied from a servo writer. There is provided a means capable of simultaneously recording servo information via the above head.

Further, in order to achieve the one object and another object, the present invention is, in addition to said means, 2
Disk rotation motor for rotating more than one disk
The flexible printed wiring board for connecting the over input and output terminals provided, connecting positions of the flexible printed circuit board
Is selected so that it is out of the movable range of four or more heads.
Additional means.

[0017]

According to the above means , one built-in lead /
The write integrated circuit and one less lane than the total number of heads
And a servo write circuit provided with a write circuit, and one read / write is performed by a signal supplied from the servo writer.
The integrated circuit and each write circuit are driven .
Therefore, one read / write integrated circuit and each write
Each head coupled to the circuit has a corresponding lead /
Servo information is simultaneously supplied through the write integrated circuit and each write circuit , thereby enabling two or more pieces of data to be supplied.
Servo writing to each recording surface on both sides of the disk can be performed simultaneously, and the time to perform servo writing to each recording surface, the so-called machine time, is significantly shorter than the conventional one.
And can perform servo writing
The number of rotations of the disk rotation for the motor is depleted at the time, two
It is possible to reduce the influence of the occurrence of the fluctuation of the rotation of the disk and the occurrence of the wobble .

According to the additional means, when the flexible printed wiring board is connected and arranged, the arrangement position is changed.
So that outside the movable range of 4 or more heads, preferably so are chosen such that the angular direction away about 60 degrees in the positive and negative directions from the movable range of the head, during the rotation of the disk rotating motor The generated noise is extremely unlikely to be guided to any one or more heads via the flexible printed wiring board, and as a result, at the time of servo writing, reading of recorded data from a disk, and the like ,
Extremely small that the rate at which noise is superimposed on the information
Can be.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1A and 1B are configuration diagrams showing the entire structure of a hard disk drive according to the present invention in a state where a lid is placed, wherein FIG. 1A is a top view, FIG. (c) is a side view of the short side, and (d) is a configuration diagram of a disk rotation motor.

In FIG. 1, 1 is a hard disk drive main body, 2 is a lid, 2 'is a label, 4 is a disk rotation motor (spindle motor), 5 is a rotation axis of the disk rotation motor 4, and 6 is a flexible printed wiring. Board (F
PC), 7 are holes for simultaneous servo writing provided on the lid 2.

The entire upper surface of the hard disk drive main body 1 is hermetically closed by a lid 2 with an O-ring interposed, and a servo write hole 7 into which a servo write pin is inserted is formed in the lid 2. I have. An axis portion of the disk is attached to a rotation shaft 5 of the disk rotation motor 4, and a flexible printed wiring board 6 is led out from a lower portion of the disk rotation motor 4.

FIG. 2 is a top view showing the entire structure of the hard disk drive with the lid removed.

In FIG. 2, 3 is a disk, 8 is a head transfer mechanism, 9 is a head (magnetic head), 10 is a support spring, 11 is a swing arm, 12 is a support shaft, 13 is a coil, 14 is a lead wire, 15 Is the voice coil motor, 1
6 is a stopper pin, 17 is a solenoid, 18 is an operating lever, 19 is a printed circuit board, 20 is a read / write integrated circuit, 21 is an input / output terminal, 22 is a connection pin for simultaneous servo writing, and 23 is an operating lever rotating shaft. In addition, the same components as those shown in FIG. 1 are denoted by the same reference numerals.

The head transfer mechanism 8 includes a swing arm 11 rotatably attached to a support shaft 12 and a support spring 1 attached to one end of the swing arm 11.
0, a head 9 attached to the inside of the distal end of the support spring 10, and a coil 13 attached to the other end of the swing arm 11. A lead wire 14 for signal transmission is connected to the head 9. I have. Voice coil motor 15
Has the coil 13 as one of the constituent elements, and functions to move the head transfer mechanism 8 by a predetermined angle in response to a command signal. A stopper pin 16 for preventing the head transfer mechanism 8 from moving beyond a required angle projects into the voice coil motor 15, and the stopper pin 16 is used to move the coil 13 when the head transfer mechanism 8 is excessively moved. It is configured to contact the inner part. The solenoid 17 controls the movement of the head transfer mechanism 8 together with the operation lever 18 and releases the restriction. The operation lever 18 has projections at both ends and rotates about the operation lever rotation shaft 23. It is freely supported. One protrusion of the operating lever 18 is engaged with an engaging pin provided on the swing arm 11 of the head transfer mechanism 8, and the other protrusion is in contact with the actuator of the solenoid 17. It is urged (biased) clockwise by a mainspring (not shown).

The printed circuit board 19 is mounted on the chassis of the hard disk drive main body 1. The printed circuit board 19 includes a read / write integrated circuit 20,
An input / output terminal 21, a connection pin 22 for simultaneous servo writing, and other necessary components connected to a control circuit board (not shown) provided on the rear surface of the chassis are arranged, and necessary wiring is made. Is what it is.

[0027] In this case, in FIG. 2, the disc 3 is shown only one, number number of head transport mechanism 8 also one (head 9 along with it, a total of two on each one on both sides of the disc 3 )
Only shown . However, in this embodiment,
It includes two or more than a stacked configured disk 3
Since the upper number is used, the number of the head transfer mechanisms 8 configured to be stacked also increases according to the number of disks 3 used.
To those, for example, when <br/> the disc 3 is used two also becomes two numbers of the head transport mechanism 8, which
The number of heads used is to four.

In the hard disk drive having the above configuration, the following operation is performed roughly.

First, when the hard disk drive is not operating, the energization of the solenoid 17 is cut off and the operating lever 1 is turned off.
8 is rotated clockwise by the elastic bias of the mainspring, whereby the one protrusion of the operating lever 18 is engaged with the engaging pin of the swing arm 11, and the head transfer mechanism 8 is moved in the maximum counterclockwise direction. State, that is,
The head 9 is placed at the innermost peripheral position of the disk 3, and the head transfer mechanism 8 is locked.

Next, when the hard disk drive enters an operating state in response to a command from a host computer (not shown), the solenoid 17 is energized and its actuator is retracted. In this state, the operating lever 18
Is rotated counterclockwise against the elastic bias of the mainspring, and the one protrusion is disengaged from the engagement pin, so that the head transfer mechanism 8 can freely rotate, that is,
The head transfer mechanism 8 enters the unlocked state.

Here, when the control circuit executes the zero track restore, the head transfer mechanism 8 moves to the zero track, reads necessary information, and continues until the next command comes from the host computer or the control circuit. We are waiting at this position.

Subsequently, when a data write or read command is output from the host computer, the control circuit executes a seek operation, and a control current is supplied to the coil 13 of the head transfer mechanism 8, whereby a head transfer is performed. The mechanism 8 seeks to the target track. After the execution of the seek, the head transfer mechanism 8 performs signal writing to the disk 3 or signal reading from the disk 3.

In the subsequent operations, any one of the above operations is repeatedly executed based on a write or read command from the host computer.

As described above, writing and reading of a signal are performed as follows.
Generally, the hard disk drive has one read / write integrated circuit 20, since the operation is performed on a specific track of the disk.

In the hard disk drive shown in FIGS. 1 and 2, when performing simultaneous servo writing on a plurality of media, the read / write integrated circuit 20 built in the hard disk drive has one
As described in the conventional hard disk device, the simultaneous servo write cannot be performed as it is as described in the conventional hard disk drive.

Therefore, in the present invention, in addition to the one read / write integrated circuit 20, a write integrated circuit having a number smaller by one than the total number of heads 9 used is provided, and these write integrated circuits are provided. A simultaneous servo write circuit board is provided which enables the output of the read / write integrated circuit to be coupled to a head not selected by the one read / write integrated circuit 20.

FIG. 3 is a circuit diagram showing an embodiment of the simultaneous servo write circuit board. In this example, the number of disks 3 is two and the number of heads is four. This shows a certain case.

In FIG. 3, 9-0 is the 0th head,
9-1 is the first head, 9-2 is the second head, 9
-3 is a third head, 24 is a simultaneous servo write circuit board, 25 is a first write integrated circuit, 26 is a second write integrated circuit, 27 is a third write integrated circuit, and 28 is a simultaneous servo write circuit I / O terminals on the servo and rack writer (not shown) side of the board 24, 29 are I / O terminals on the hard disk drive side of the simultaneous servo write circuit board 24, 30,
31, 32, 33, 34, and 35 are external capacitors.

Then, the simultaneous servo write circuit board 24
Has a first write integrated circuit 25, a second write integrated circuit 26, a third write integrated circuit 27, and a plurality of external capacitors 30 to 35, and the inside is connected and connected as shown in the figure. I have. Simultaneous servo write circuit board 2
4 is a ground potential terminal (GND), a power supply voltage terminal (Vcc), and a level 1 (Hi) at a lead (R).
gh), the read / write (R / W) command signal supply terminal which becomes level 0 (Low) at the time of write (W), and the current flowing through the heads 9-1 to 9-3 are set to appropriate values by an external resistor. Write current terminals (WC ₁ , W
C ₂ , WC ₃ ), a write data in (WDI) signal supply terminal which alternately repeats level 1 and level 0 at the time of write (W) and level 1 at the time of read (R).
Light integrated circuit 25 to the level 1 to the operating time of failure of 27, the write unsafe as a level 0 in other cases _{(WUS 1, WUS 2, WUS} 3) and a signal output terminal. On the other hand, the input / output terminal 29 of the simultaneous servo write circuit board 24 has a center tap signal (Vc) which becomes level 1 at the time of write (W) and level 0 at the time of read (R).
t), which are connected to both ends of the first to third heads 9-1 to 9-3, and are connected to the write data in (WD).
I) It is turned on and off alternately according to the signal levels 1 and 0,
From the center tap signal output terminal to the heads 9-1 to 9-
3 (H _1X ,
H _1Y , H _2X , H _2Y , H _3X , H _3Y ).

Although not shown, the read / write integrated circuit 20 has input / output terminals similar to the input / output terminals 28 and 29 of the simultaneous servo write circuit board 24. Is a read / write integrated circuit 2
0 in conjunction with the function associated with the 0th head 9-0,
That is, a function similar to the function related to the above-described first to third heads 9-1 to 9-3 performed in cooperation with the simultaneous servo write circuit board 24 and its input / output terminals 28 and 29. Is configured to be achieved.

Here, the simultaneous servo write circuit board 24 according to the present embodiment performs the following operation.

Now, the input / output terminal 2 of the simultaneous servo write circuit board 24 from the servo track writer (not shown)
8, a write command signal of an R / W command signal is supplied, and at the same time, a write data-in signal which repeats level 1 and level 0 is supplied, the first to third write integrated circuits 25 to 27 Responds to the write command signal and the write data-in signal, and outputs from the input / output terminal 29 of the simultaneous servo write circuit board 24 a center tap signal (current) that lasts for a period corresponding to the supply period of the write command signal. At the same time, the terminals H _1X , H _1Y ,
H _2X , H _2Y , H _3X and H _3Y are turned on and off alternately.

In the head drive portion of the hard disk drive, the center tap signal (current) including the read / write integrated circuit 20 is applied to each of the 0th to 3rd heads 9-0 to 9-3. Both ends of the 0th head 9-0 are simultaneously supplied to the center tap, and both ends of the 0th head 9-0 are alternately turned on / off in response to a write data-in signal.
Terminal H _0X write integrated circuit 20 are connected respectively to the H _0Y, signals supplied to the center tap of the head 9-0 (current) terminal H _0X, incorporated alternately in H _0Y.
At the same time, they are connected to both ends of the first to third heads 9-1 to 9-3, and are turned on and off alternately according to the write data-in signal from the input / output terminal 28 of the simultaneous servo write circuit board 24. Terminals H _1X , H _1Y , H _2X , H _2Y ,
H _3X, the H _3Y center tap signals to be supplied to the head 9-1 to 9-3 (current) flows alternately respectively.

As described above, in the present embodiment, when the servo command signal is supplied from the servo track writer, one of the read / write integrated circuits 20 built in the hard disk device and the one provided outside the hard disk device are provided. By the operation of the first to third write integrated circuits 25 to 27 arranged on the simultaneous servo write circuit board 24, all the heads, that is, the 0th to 3rd heads 9-0 to 9- 3 are simultaneously switched and selected. In each of the above-mentioned 9-0 to 9-3, the servo write of the recording surface 0 of the first disk 3 facing the head 9-0 via the 0th head 9-0 is performed by the first The servo write on the recording surface 1 of the first disk 3 facing the head 9-1 via the No. 9 head 9-1 is performed via the second head 9-2.
-2, the servo write on the recording surface 2 of the second disk 3 is performed by the third head 9-3 via the third head 9-3.
-3, the servo write of the recording surface 3 of the second disk 3 is simultaneously executed.

Therefore, according to the present embodiment, by providing the simultaneous servo write circuit board 24 outside the hard disk drive, all the heads 9-0 to 9-3 are simultaneously switched and selected when the servo command signal is supplied. Since the servo writing for all the recording surfaces 0 to 3 is performed at the same time, the time for performing the servo writing, that is, the so-called machine time can be reduced.

Further, according to the present embodiment, when performing the servo writing, the time for rotating the disk 3 is minimized, so that the rotation fluctuation of the disk 3 and each head 9-0 are reduced.
9-3 can be reduced.

In this case, all the heads 9-0 to 9-9
The simultaneous selection of -3 and the simultaneous servo write of all the recording surfaces 0 to 3 are performed by connecting a predetermined connection jig (not shown) to the simultaneous servo write connection pin 22 on the printed circuit board 19 shown in FIG. This is executed by being fitted through the simultaneous servo write hole 7 of the lid 2, and the input / output terminal 29 of the simultaneous servo write circuit board 24 and the head input of the drive part of the hard disk drive are inserted by fitting the connection jig. In other words, the portion, that is, the connection with the simultaneous servo write connection pin 22 (the portion indicated by the dotted line in FIG. 3) is electrically connected. With the configuration as in this embodiment, the number of connection pins 22 for simultaneous servo write is only seven, and even in a general case, when the number of heads 9 is n, the simultaneous servo write The number of write connection pins 22 is (n-1)
× 2 + 1 is sufficient.

It should be noted that since the servo information is to be determined, that is, the servo write is performed at the time of manufacturing the hard disk device, it is necessary to hide the simultaneous servo write hole 7 in the hard disk device after the servo write is completed. In order to seal the inside of the device, a label 2 'is attached to the lid 2 as shown in FIG.

FIG. 4 is a partially transparent configuration diagram showing a configuration of a disk rotation motor portion in the hard disk device according to the present invention.

In FIG. 4, reference numeral 36 denotes a flexible printed wiring board having a conventional arrangement, and other components which are the same as those shown in FIG. 2 are denoted by the same reference numerals.

In the conventional hard disk drive, the flexible printed wiring board 36 is mainly led out from the disk rotation motor 4 as shown by the dotted line in FIG. This noise is mainly noise of about 600 to 1800 c / sec generated at the time of phase switching of the motor 4 and external noise superimposed on the power supply.)
Are superimposed on the read signal when reading the disk 3, and also affect the write signal when writing to the disk 3.

On the other hand, in the present embodiment, FIG.
As shown by the solid line, the direction in which the flexible printed wiring board 6 is led out from the disk rotation motor 4 will be specifically described in a movable range of the head transfer mechanism 8, particularly a direction far away from the movable range of the head 9. And a position about 60 degrees away from the movable range of the head transfer mechanism 8 in the negative direction (counterclockwise).

As described above, when the lead-out direction of the flexible printed wiring board 6 is selected, the motor 4 for rotating the disk is selected.
The ratio of the noise generated at the time of being superimposed on the read signal or the write signal at the time of reading or writing of the disk 3 becomes considerably small. I was able to confirm.

In this embodiment, the head transfer mechanism 8
Is selected so as to be located at a position about 60 degrees in the negative direction from the movable range of the flexible printed wiring board 6 according to the present invention. However, the leading direction of the flexible printed wiring board 6 according to the present invention is not limited to the above-described position. For example, the position may be selected so as to be about 60 degrees in the positive direction (clockwise) from the movable range of the head transfer mechanism 8, or may be selected to be about 60 degrees or more in both the positive and negative directions from the movable range. Or may be selected so as to be separated from the movable range by an angle slightly smaller than 60 degrees in both the positive and negative directions.

As described above, according to the present embodiment, the leading direction of the flexible printed wiring board 6 is
Is selected so as to be far away from the movable range of the disk drive, so that the noise generated from the disk rotation motor 4 is minimized from being guided to the head 9 via the flexible printed wiring board 6, and The noise superimposed on the read signal and the write signal at the time of reading or writing of No. 3 can be extremely reduced.

[0056]

As described above, according to the present invention,
For two or more discs and the accompanying four or more heads
One built-in read / write integration circuit
The number of write circuits one less than the total number of paths and heads.
Equipped with a digitized servo write circuit and supplied from a servo writer
The read / write integrated circuit and each
Since the write circuit is driven, one read /
Write integrated circuit and each head connected to each write circuit
Heads are simultaneously switched and selected.
Servo information through the write / write integrated circuit and each write circuit
Are supplied at the same time, so that two or more
Servo writing to each recording surface on both sides of the disk can be performed simultaneously, and the time to perform servo writing to each recording surface , the so-called machine time, is significantly shorter than that of the conventional one.
This has the effect that the length can be shortened .

According to the present invention, two or more discs
Simultaneously performing servo write to the recording surfaces on the both sides of the click
This allows the disk rotation mode to be used when performing servo writing.
Rotation number depleted of Ta, is possible to reduce two or more the influence of occurrence and fluctuation of occurrence of rotational fluctuation of the disk there is an effect that it <br/>.

[0058] Further, according to the present invention, when connecting place the flexible printed wiring board, the arrangement position four
Because it is chosen to be outside the movable range of the above head, any one or more noise generated during rotation of the disk rotating motor through a flexible printed circuit board
It is extremely unlikely to be guided to the upper head,
As a result, during servo writing or reading recorded data from the disc
There is an effect that the rate of superimposition of noise on information can be extremely reduced, for example, when data is taken.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an entire structure of a hard disk drive according to the present invention in a state where a lid is provided.

FIG. 2 is a top view showing the entire structure of the hard disk drive with a cover removed.

FIG. 3 is a circuit diagram showing an embodiment of a simultaneous servo write circuit board.

FIG. 4 is a partially transparent configuration diagram showing a configuration of a disk rotation motor portion in the hard disk device according to the present invention.

FIG. 5 is a schematic configuration diagram showing a head drive portion of a conventional hard disk device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Hard disk drive main body 2 Lid 3 Disk 4 Disk rotation motor (spindle motor) 5 Rotation axis of disk rotation motor 4 6 Flexible printed wiring board (FPC) 7 Servo light hole provided in lid 2 8 Head transfer Mechanism 9 Head (magnetic head) 9-0 0th head 9-1 1st head 9-2 2nd head 9-3 3rd head 10 Support spring 11 Swing arm 12 Support shaft 13 Coil DESCRIPTION OF SYMBOLS 14 Lead wire 15 Voice coil motor 16 Stopper pin 17 Solenoid 18 Operation lever 19 Printed circuit board 20 Read / write integrated circuit 21 Input / output terminal 22 Connection pin for simultaneous servo writing 23 Operation lever rotation axis 24 Simultaneous servo write circuit board 25 First Write integrated circuit 26 Second write integrated circuit 27 Third write integrated circuit 28 Input / output terminal of simultaneous servo write circuit board 24 29 Input / output terminal of simultaneous servo write circuit board 24 30, 31, 32, 33, 34, and 35 are external capacitors

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hiroshi Nakano 1-7 Yukiya Otsuka-cho, Ota-ku, Tokyo Alps Electric Co., Ltd. (56) References JP-A-3-54778 (JP, A) (58) Field surveyed (Int.Cl. ⁶ , DB name) G11B 20/10

Claims (2)

(57) [Claims] 1. A system comprising: two or more disks, four or more heads respectively arranged on both sides of the two or more disks, one built-in read / write integrated circuit, and a total number of the heads. A servo write circuit provided with one less write circuit, wherein the one read / write integrated circuit is connected to one head, and the write circuits are individually connected to the corresponding remaining heads. Coupled to each other by a signal supplied from a servo writer.
A hard disk drive, wherein: a plurality of read / write integrated circuits and each of the write circuits are driven, and servo information can be simultaneously recorded on both surfaces of the at least two disks via the at least four heads. 2. The hard disk drive according to claim 1, further comprising: a flexible printed wiring board for connecting a disk rotating motor for rotating the two or more disks to an input / output terminal; A hard disk drive wherein a connection arrangement position is selected so as to be out of a movable range of the four or more heads.