JPH03212855A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To attain high density, large capacity, and light weight by making magnetic heads arranged at the outside plane sides of a pair of magnetic disks being arranged confronting by interposing a plate whose both planes are pro vided with Bernoulli effect access the prescribed position of each magnetic disk. CONSTITUTION:This device is comprised mainly of two flexible magnetic disks 1, 1, a Bernoulli plate 2 neighbored and arranged between those disks and whose plane confronting with the magnetic disks 1, 1 forms a plane with the Bernouli effect, a spindle motor 3 to drive rotatably the magnetic disks 1, 1, and a stepper mechanism 5 which comprises a magnetic head access means to turn an arm 6 to seek two pairs of magnetic heads 4, 4 and 4, 4 in the radius direction of the magnetic heads 1, 1 etc. By rotating the magnetic disk in a fixed state, no rolling occurs in the magnetic disk, and the tracing of the mag netic head can be stabilized. In such a way, the high density of a track, the large capacity, and the light weight can be attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic disk device, and more particularly to a magnetic disk device that uses a flexible magnetic disk in a fixed manner.

(Prior Art) Conventionally, a fixed magnetic disk device generally uses a hard disk as a magnetic recording medium.An example of the above configuration is a magnetic disk device as shown in US Pat. No. 4,729,74.

In recent years, personal computers and word processors have become rapidly popular. Also, portable computers have recently become popular. Along with this, there is a desire for the emergence of inexpensive and lightweight magnetic disk devices.

[Problem to be solved by the invention]

In magnetic disk devices using conventional hard disks,
Since the magnetic disk itself is expensive, there was a cost burden. Furthermore, since the magnetic disk is a hard type, there are problems such as the overall weight of the magnetic disk device being heavy and the surface of the magnetic disk being damaged due to impacts such as collision with the magnetic head due to vibration. Furthermore, in a magnetic disk device using a flexible magnetic disk, the magnetic disk is removable from the magnetic disk device. Therefore, to prevent crosstalk from occurring, the track spacing of the magnetic disk is provided with a certain margin.

Therefore, it is difficult to increase density and capacity.

In view of the above problems, an object of the present invention is to reduce the weight of a magnetic disk device, improve vibration resistance, and further increase the density and capacity of a flexible magnetic disk. It is said that

[Means to solve the problem]

Therefore, in the magnetic disk device according to the present invention, there is provided a flat plate having the Bernoulli effect on both sides, a pair of flexible magnetic disks arranged facing each other with this flat plate interposed therebetween, and an outer surface of each of these magnetic disks. A magnetic head disposed on the side, a magnetic disk support means for rotatably supporting each of the magnetic disks in a fixed state, and a magnetic head access means for accessing each of the magnetic heads to a predetermined position on each magnetic disk. The main point is that

Further, the present invention is characterized in that each of the magnetic heads is supported by a support that attracts each of the magnetic disks toward each of the magnetic heads by the flow of gas on the surface facing each of the rotating magnetic disks.

(Operation) By rotating a flexible magnetic disk at high speed in a fixed state, the magnetic disk becomes a flat plate instead of a corrugated peg, and the trace of the magnetic head becomes stable, resulting in high density and large capacity. In addition, by using a flexible magnetic disk, the weight of the entire device can be reduced.Furthermore, it is possible to prevent head crashes caused by collisions between the magnetic head and the magnetic disk, as in the case of hard disks.

Furthermore, it goes without saying that the capacity can be increased by using two flexible magnetic disks compared to one disk.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a plan view of a magnetic disk device according to an embodiment of the present invention, and FIG. 2 is a side sectional view of the magnetic disk device. The magnetic disk device shown in these figures is arranged in close proximity between two flexible magnetic disks 1.1 and between these two magnetic disks 1.1.
A Bernoulli plate 2 whose opposing surface is disk-shaped and has a Bernoulli effect, and these magnetic disks 1
．． a spindle motor 3 that rotationally drives the magnetic disk 1.1, two magnetic heads 4.4 that record and/or reproduce information on the magnetic disk 1.1, and the magnetic head 4.4.
an arm 6.6 that supports the magnetic head 4.4 at its tip end, a stepper drive mechanism 5 that constitutes a magnetic head access means that rotates the arm 6 in order to seek the magnetic head 4.4 in the radial direction of the magnetic disk 1.1; It mainly consists of a base plate 7 made of aluminum die-casting, for example, on which each component is mounted and supported.

The Bernoulli plate 2 has a thickness of about 0.3 m, and its outer edge is polished outward from the outer periphery of the magnetic disk 1.1. Further, the surface of the Bernoulli plate 2 is etched so that this outer edge portion protrudes in several to several white directions in the direction of the magnetic disk 1.1. Furthermore, this Bernoulli plate 2 is fixed to the base plate 7. On the other hand, the magnetic disk 1.1 is fixed to a spindle head 10, which is a rotational support means formed in the rotating part of the spindle motor 3, with three screws 8, respectively, via a spacer (not shown). A PG magnet 11 is provided on the upper surface of this spindle head 10. A PG sensor (not shown) composed of a coil or the like is provided above the position corresponding to the PG magnet 11 provided on the upper surface of the spindle hub 10, and the magnetic flux of the PG magnet 11 is adjusted every rotation of the disk. It is detected by a PG sensor (not shown) and controls the rotational speed of the magnetic disk 1.degree.

The spindle motor 3 constructed as described above is mounted on the base plate 7 as shown in FIG. Next, a stepper drive mechanism 5, which is a magnetic head access means, is mounted on the base plate 7. This stepper drive vJ mechanism 5 has a rotating shaft 12 . At the tip of this rotating shaft 12, two binions are stacked one on top of the other and further connected to each other with a spring.

By configuring the two binions as described above, it is possible to prevent looseness in engagement with the rack 13, which will be described later, and to improve the accuracy of head positioning.

The other end of the arm 6.6, to which the magnetic head 4.4 is attached, is formed with a rack 13 that engages the binion, and the arm 6.6 is connected to an arm support shaft 14.
It is rotatably supported in accordance with the rotation of the rotating shaft 12 about the fulcrum. This arm support shaft 14 is fixed on the base plate 7. The magnetic head 4.4 moves in the radial direction on the surface of the magnetic disk as the arm 6.6 rotates around the arm support shaft 14, and performs recording and/or reproduction on a predetermined track.

As shown in FIG. 3, the magnetic disk 1.1, the Bernoulli plate 2, the magnetic disk 1.1, and the magnetic head 4.4 are arranged parallel to each other. Further, the magnetic disk 1.1 and the magnetic head 4.4 are arranged close to each other.

The upper cover 8 is fixed to the base plate 7 configured as described above with four screws 18.

Further, a connector (not shown) for connecting to a computer is provided at the tip of the control board 16.

Next, the aforementioned magnetic head will be explained with reference to FIG.

As shown in FIG. 4, a gap G is formed in the magnetic head 4. As shown in FIG. Further, around this gap G, a curved surface 4B is formed which comes into sliding contact with the magnetic disk 1. An inclined portion 4A is formed diagonally downward from the air inflow end side of the curved surface 4B. Further, on the air outflow end side of the curved surface 4B, a step portion 4C having 100 or less steps is vertically provided. An inclined portion 4D is provided diagonally downward from the lower end of the stepped portion 4C.

Next, the effect will be explained. For convenience, the direction of rotation of the magnetic disk 10 is set as arrow B as shown in FIG. As the magnetic disk 1 rotates, an air flow enters from the air inflow end side of the magnetic head 4. However, a part of the airflow flows down along the inclined portion 4A (in the direction of arrow a). therefore,
The airflow (in the direction of the arrow) that enters between the magnetic disk 1 and the curved surface 4B is smaller than in the case without the inclined portion 4A.

Therefore, since the amount of dust in the airflow passing over the gear G is reduced, the adverse effect of dust on the magnetic disk 1 and the magnetic head 4 is reduced. Furthermore, the air flow that has passed over the gear knob G rapidly descends due to the stepped portion 4C, and flows out of the magnetic head 4 along the sloped portion 4D (in the direction of arrow C in FIG. 4). Therefore, the air that has passed over the gear knob G This prevents the water from flowing back toward the gear part. In this way, in the magnetic head 4 having the above structure, an air flow with relatively little dust flows smoothly between the magnetic disk 1 and the gap G of the magnetic head 4, so that the magnetic head is less affected by dust. The lifespan of 4 itself will also be extended.

The magnetic head 4 explained above is shown in Figures 5 (^) and (B).
It is supported by a pad 15 that serves as a support body shown in .

As shown in FIGS. 5(^) and 5(B), the pad 15 is formed into a substantially fan shape. A head attachment hole 15A in which the magnetic head 4 is attached is formed in the center of the pad 15.

A tapered portion 15D is formed on the air inflow end side of the pad 15 (on the upstream side of the rotation of the disk).

A side surface 15E on the outer circumferential side of the magnetic disk and a side surface 15F on the inner circumferential side of the pad 15 are formed in an arc shape with approximately the same curvature as the circumference of the magnetic disks 1,1.

Further, a side surface 15E of the pad 15 also has a side surface 15B in which one end 15G is closed at the center of the pad 15.

It is formed to have an inner surface 15H1151 with the same curvature as the arc shape of 15F. In addition, the groove 1 of the pad 15
A pair of narrow grooves 15C are formed on both sides of 5B so that the grooves are deep on the tapered part 15D side at the air inflow end and gradually become shallower toward the air outflow end. Further, the width is wide on the tapered portion 15D side and gradually narrows toward the air outflow end side.

Next, the effect will be explained. As shown above, first, by forming the tapered portion 15D as shown in FIG. It becomes easier to flow into. Also,
The airflow caused by the rotation of the magnetic disk 1 is caused by the rotation of the magnetic disk 1.
It flows in almost the same arc shape. Therefore, as mentioned above,
Since the side surface 15E on the magnetic disk circumferential side and the side surface 15F on the inner circumferential side of the pad 15 are formed in an arc shape with approximately the same curvature as the circumference of the magnetic disk 1, air flows smoothly along the side surface of the pad 15. , unnecessary force in the magnetic disk radial direction that is applied to the pad 15 by the air flow is reduced. Furthermore, the airflow enters between the magnetic disk 1 and the pad 15 from the tapered portion 15D, and the airflow flows through this gap at high speed. This airflow flows into the groove portion 15B1. : By flowing in, negative pressure is generated in the groove portion 15B. Therefore, the magnetic disk 1 is attracted to the pad 15 side.

The pad 15 described above is attached to the tip of the arm 6 and supports the magnetic head 4. Then, the stepper drive mechanism 5 moves the magnetic disk 1.degree. 1 onto the magnetic disk 1.degree. 1, and performs recording and/or reproduction on a predetermined track.

The movement of the magnetic bed 4 on the disk surface is controlled by the control board 1.
This is done by the ilJ 11 circuit located at 0.

Next, a servo mechanism for controlling the position of the magnetic head 4 to a predetermined track on the magnetic disk 1 will be explained.

Currently, flexible magnetic disks generally use organic polymer films such as polyethylene terephthalate as their base material. Further, this flexible magnetic disk is made by pulling out the required portions of an organic polymer film from a roll and punching them into a circular shape. Therefore, when a disk is punched out, this film is always subjected to tension in the longitudinal direction of the roll body, so that the punched disk has anisotropy of elongation in the direction of tension. For this reason, the magnetic disk exhibits a substantially elliptical shape as shown in FIG. 6 when affected by temperature and humidity.

FIG. 6 shows a flexible magnetic disk with elongation anisotropy.

As shown in Figure 6, with the center 0 of the disk as a reference,
For convenience, the direction in which elongation due to tension exists is set as the long axis X (horizontal line), and the direction perpendicular to the long axis is set as the short axis Y' (vertical line). In this embodiment, at least one servo sector is provided in the long axis X direction and at least one servo sector is provided in the short axis Y direction. A zone P where no data is written is formed on the innermost side of the magnetic disk 1, and a data zone D and servo sectors 81 and 82 are formed on the outer side in the radial direction.

The servo sector is a servo sector S formed in the long axis X direction.
1 and a servo sector S2 formed in the short axis Y direction, both of which are located at right angles to the center of the magnetic disk.

Then, as shown in FIG. 7, servo sectors S1 and S2
For each recording track T, servo signals F are alternately written at the same frequency in a staggered manner at positions equidistant from the center line C in the longitudinal (circumferential) direction. In this case, since writing is performed with the same magnetic head 4, the track width of the servo signal F and the recording track T matches the length of the gap G of the magnetic head 4, and the off-track is
This is caused by the position of the gap G being shifted from the desired recording track T.

FIG. 8 shows a flowchart of head position correction by the servo mechanism of the present invention.

First, the magnetic head 4 reads the servo information signals of each of the servo sector S1 in the long axis X direction and the servo sector S2 in the short axis Y direction in FIG. 6, and compares the servo correction values of the servo sectors S1 and S2. The presence or absence of the recording track T is confirmed by comparing the servo correction values. Here, if there is no eccentricity, the next servo information signal is read, but if there is eccentricity, the amount of eccentricity is calculated and the amount of eccentricity is corrected. Then, the eccentricity amount is compared with a preset correction amount calculation table. By comparing with this correction amount calculation table, the desired recording track T
Calculate the correction amount up to and output the control using this correction amount. With the correction means, the gap G of the magnetic head 4 is
If it is located at the predetermined track position, tracking is performed as is, and if it is not located at the set predetermined track position, the position MilII control is performed again.

According to the above embodiment, a flexible magnetic disk 1.
1, it is possible to achieve lighter weight and lower cost than conventional hard magnetic disks. Moreover, the magnetic disk 1,
Due to the flexibility of the magnetic head 1, the magnetic head 4 does not damage the magnetic disk 1.1 and the magnetic head 4 due to shocks, vibrations, etc., and has excellent vibration resistance. In addition, by arranging the Bernoulli plate 2 in close proximity between the magnetic disks 1.1, the 2
This prevents the two magnetic disks 1.1 from coming into contact with each other or coming into close contact with each other. By having the air inflow hole 9, the spindle motor 3 can be rotated at a high speed of about 360 rpm.
Air flows in through the air inflow hole 9 and flows out from the inside to the outside of the surface of the Bernoulli plate 2, thereby preventing the magnetic disk 1.1 from adhering to the Bernoulli plate 2. Furthermore, since the structure allows the use of two magnetic disks 1.1, the storage capacity increases by one disk.

Further, by making the magnetic disk 1 fixed, the tracing of the magnetic head 4 becomes stable, and it is possible to increase the track density and capacity.

Further, since the magnetic disk 1.1 and the magnetic head 4.4 are extremely sensitive to dust, the magnetic disk device may be housed in an airtight container. In particular, by isolating at least the magnetic disk 1.1, the magnetic heads 4, 4, and the rotational support means 10 from the outside air, it is possible to prevent dust from adhering to the magnetic disk 1.1, etc., and improve recording and/or reproducing performance. do.

〔Effect of the invention〕

As described above, in the present invention, since the flexible magnetic disk is fixed to the rotating handheld means, the tracing of the magnetic head is stabilized and the track density is increased.

High capacity is possible. Further, since a flexible magnetic disk is used as the magnetic disk, it is lighter and thinner than a hard magnetic disk, so it is possible to reduce the weight and size. Also, in the rotation of the magnetic disk,
Since the support of the magnetic head has the effect of attracting the magnetic disk, the frequency of damage to the magnetic disk is much lower than with a type in which the magnetic head is pressed against the magnetic disk. Further, by using two magnetic disks, many effects such as an increase in storage capacity can be achieved.

[Brief explanation of drawings]

FIG. 1 explains a first embodiment of the present invention. FIG. 2 is a side sectional view of the magnetic disk device. FIG. 3 is a side cross-sectional view of essential parts showing the structure of a magnetic head, a magnetic disk, and a Bernoulli plate. FIG. 4 is a side sectional view of the magnetic head. FIG. 5(A) is a plan view of the magnetic head support device, and FIG. 5(B) is a sectional view thereof taken along the line AA'. FIG. 6 is a plan view of a flexible magnetic disk on which servo sectors are arranged. FIG. 7 is a configuration diagram of a servo sector. Figure 8 shows 70 degrees of head position correction using servo sectors.
- diagram of a chart; DESCRIPTION OF SYMBOLS 1...Flexible magnetic disk, 2...Bernoulli plate, 4...Magnetic head, 10...Rotation support means (spindle hub) 15...Magnetic head support pad).

Claims (2)

[Claims] (1) A flat plate having the Bernoulli effect on both sides, a pair of flexible magnetic disks placed opposite each other with this flat plate placed between them, and a pair of flexible magnetic disks placed opposite to the surface of each of these magnetic disks that faces the flat plate. , a magnetic head for recording and/or reproducing information on each of the above-mentioned disks; a magnetic disk support means for rotatably supporting each of the above-mentioned magnetic disks in a fixed state; A magnetic disk device comprising a magnetic head access means for accessing a position. (2) Claim 1, wherein each of the magnetic heads is supported by a support that attracts the magnetic heads toward each of the magnetic heads by means of a gas flow on the surface facing each rotating magnetic disk. Magnetic disk device described in section.