JPH06111214A - Floppy disk drive apparatus and its driving method - Google Patents

Abstract

PURPOSE:To obtain an inexpensive floppy disc drive apparatus which is compatible with a conventional floppy disc drive apparatus by making the maximum memory capacity at the unformatted time 8 megabytes. CONSTITUTION:A needle 3 extending from a base 15 is engaged with a screw 2 of a stepping motor 1, thereby converting the rotation of the screw 2 into the linear motion. As a result, the base 15 is guided by a guide bar 6 to move linearly. A carriage 4 is mounted on the base 15 so that it sways centering at a point P consequent to the rotation of a second gear 18 when the carriage 4 is fitted with a pin 16, thereby allowing a first gear 17 to be meshed with the second gear 18. The sway of the carriage 4 is regulated by stoppers 19a, 19b, and the azimuth angle is hence set.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floppy disk drive device.

[0002]

2. Description of the Related Art FIG. 3 is an external view showing a needle-screw system in a conventional head positioning mechanism described in, for example, "All about floppy disk devices" (CQ Publishing). Is a screw in which a screw-shaped groove is cut in a part of the shaft of the stepping motor 1, and 3 is a needle provided on the carriage 4. The needle 3 holds the screw 2 between the screw and a screw pressing spring 5 extending from the carriage 4. It holds and engages with the groove of the screw 2 to convert the rotation of the screw 2 accompanying the driving of the stepping motor 1 into a linear motion.

A guide bar 6 slidably penetrates through the carriage 4. The guide bar 6 serves as a guide for linearly moving the carriage 4 in response to the rotation of the screw 2. 7a is a side 0 which is fixedly adhered to the carriage 4 or is bonded through a gimbal spring.
Heads 8 are screw holes, and the arms to which the side 1 heads are attached are aligned and attached to the carriage 4.

FIG. 4 is a schematic sectional view of a magnetic head portion in a conventional floppy disk drive device. The magnetic head portion includes ferrite cores 9a and 9
side 0 head 7a and side 1 head 7 with b formed
b is arranged so as to face each other, and a floppy disk (hereinafter referred to as FD) 10 is inserted into the gap. Data 11a and 11b are magnetically recorded on the sides 0 and 1 of the FD 10 by the core 9a of the side 0 head 7a and the core 9b of the side 1 head 7b, respectively. Further, between the data 11a and between the data 11b, there are guard bands 12a and 12b which are direct current erasing areas. Here, when the width of the data 11a and 11b is 115 μm according to the JIS standard, the width of the guard bands 12a and 12b is 72.5 μm.

The operation of the conventional floppy disk drive device (hereinafter referred to as FDD) will be described below. For example, most 3.5 inch FDDs employ the needle screw type head positioning mechanism shown in FIG. 3, and the 135 TPI, 80 cylinder type has a screw pitch that moves 0.1875 mm per track. Then, the side 0 head 7a and the side 1 head 7b have a positional relationship as shown in FIG.
F while simultaneously moving 0.1875 mm on one track
Data 11a and 11b are magnetically recorded on both sides of D10.

Therefore, the side 0 of the 3.5-inch FD10
In terms of plane, as shown in FIG. 5, ro: 39.5 mm to r
i: Up to 24.6875 mm, track pitch 0.18
75 mm (data width: 115 μm, guard band width: 7
2.5 μm) from TR00 (track 00) to TR7
Up to 9 (track 79), 80 lines are magnetically recorded and reproduced. On the other hand, on the side 1 surface, as shown in FIG.
From 38 mm to ri: 23.1875 mm, track pitch 0.1875 mm (data width: 115 μm, guard band width: 72.5 μm), TR00 (track 0
From 0) to TR79 (track 79), 80 lines are magnetically recorded and reproduced.

The guide bar 6 of the head positioning mechanism
As shown in FIG. 7, a spindle motor (hereinafter, SP
(Which is referred to as “M”) and is disposed parallel to the center of the side 0 head 7a and side 1 head 7b.
Performs magnetic recording and reproduction while always moving parallel to the SPM center in the track width direction. At this time, the gap 50 and the SPM center are offset by 0.35 mm.

The data recorded / reproduced by the conventional 3.5-inch FDD is roughly classified as shown in Table 1 according to the storage capacity at the time of unformatting.

[0009]

[Table 1]

In the conventional 3.5-inch FDD, the storage capacity has been expanded by shortening the recording wavelength and increasing the number of bits per unit length without changing the track density (TPI).

Further, FIGS. 8A and 8B show the tape format of the VHS system and the β system of the conventional VTR, and FIGS. 7 shows a recording / reproducing mechanism unit and an azimuth recording process of the magnetic recording device described in Japanese Patent Publication No. 6601. In both figures, the data patterns with azimuths of two adjacent tracks are recorded by magnetic heads having two different azimuth angles. In FIG. 9, the angle formed by the magnetization patterns of the two tracks is 8
It is set to 0 ° to 100 °.

[0012]

Since the conventional FDD is constructed as described above, it is necessary to further shorten the recording wavelength in order to increase the storage capacity, and for that purpose, the gap length is narrowed, There was a problem that the processing accuracy had to be improved.

Further, there is a problem that the guard band 12 in the DC erased area hinders the improvement of the recording density.

In addition, conventional 4-megabyte FDD and 2
The megabyte FDD has complete backward compatibility, and even if an FDD with an increased storage capacity is commercialized in the future, this full backward compatibility will be required. However, if the track pitch and the data width are changed, the compatibility with the conventional FDD will be lost, and with the gap length that can be recorded / reproduced without waveform processing of the recording density of 34868 BPI or more, this complete backward compatibility is ensured. There was also the problem that it would not be possible.

The present invention has been made to solve the above problems, and uses a magnetic head mounted in a conventional 4-megabyte FDD to reduce the storage capacity during unformatting to 8 megabytes. It is an object of the present invention to provide an inexpensive floppy disk drive device having a high storage capacity and a driving method thereof, which is fully backward compatible with each FDD of 1 MB, 1.6 MB, 2 MB and 4 MB.

[0016]

According to a first aspect of the present invention, there is provided a floppy disk drive device having a first read / write gap parallel to a normal line of a floppy disk.
One or more heads having a second read / write gap having a positive azimuth angle with respect to the normal of the floppy disk and a third read / write gap having a negative azimuth angle with respect to the normal of the floppy disk; , Head moving means for moving the head parallel to the normal line of the floppy disk.

The driving method of the floppy disk drive device according to the second invention of the present invention is the first read / write gap parallel to the normal line of the floppy disk.
One or more heads having a second read / write gap having a positive azimuth angle with respect to the normal of the floppy disk and a third read / write gap having a negative azimuth angle with respect to the normal of the floppy disk; , A head moving means for moving the head parallel to the normal line of the floppy disk, and the storage capacity of the floppy disk is 8
In the case of megabyte, the head is moved by the head moving means to alternately switch the second and third read / write gaps for recording / reproduction, and when the storage capacity of the floppy disk is 4 megabytes or less, The head is moved by the moving means, and recording / reproducing is performed by the first read / write gap.

[0018]

In the first aspect of the present invention, the first read / write gap parallel to the normal line of the floppy disk and the head moving means, or the positive and negative azimuth angles with respect to the normal line of the floppy disk are formed. Second and third
By selecting the combination of the read / write gap and the head moving means, it is possible to adapt to floppy disks of various storage capacities.

According to the second aspect of the present invention,
When the storage capacity of the floppy disk is 8 megabytes, the head is moved by the head moving means to alternately switch the second and third read / write gaps for recording and reproduction, and the storage capacity of the floppy disk is 4 megabytes. In the following cases, since the head is moved by the head moving means and recording / reproducing is performed by the first read / write gap, the azimuth recording does not require a guard band on the 8-megabyte FD to improve the recording density. As a result, the full backward compatibility of the 4-megabyte FDD can be secured.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. Example 1. 1A and 1B are a plan view and a side view of a main portion of a floppy disk drive device showing a first embodiment of the present invention, respectively, and a conventional floppy disk shown in FIGS. 3 and 4 in the drawing. The same or corresponding parts as those of the drive device are designated by the same reference numerals, and the description thereof will be omitted.

In the figure, 13 is an arm to which a side 1 head 7b is attached, and this arm 13 is screwed into a screw hole 8 of a carriage 4 by a positioning adjusting screw 14. Reference numeral 15 is a base, and 16 is a pin that is erected on the base 15. The pin 16 is inserted into a hole formed at the position of the swing center axis P of the carriage 4 so that the carriage 4 can rotate on the base 15. It is installed. 17 is a first gear attached to the carriage 4, 18 is a base 1
Second gears 19a and 19b, which are attached to the first gear 17 and mesh with the first gear 17, are stoppers for setting the azimuth angle, which are provided on the base 15, respectively.

Here, the read / write gap of the head is mounted parallel to the carriage 4 with an offset of 0.35 mm with respect to the SPM center line, engages with the groove of the screw 2, and linearly rotates the stepping motor 1. The needle 3 and the screw retainer 5 that convert into movement are attached to the base 15, and the guide bar 6 that guides the movement of the carriage 4 according to the rotation of the screw 2 is attached to the base 15. The stepping motor 1, screw 2, needle 3 and screw retainer 5
This constitutes a head moving means.

In the floppy disk drive device thus constructed, the rotation of the stepping motor 1 is converted into a linear motion by the needle 3 engaged with the groove of the screw 2, and the base 15 is guided by the guide bar 6. SP
Move parallel to the center line of M (normal direction of FD). At this time, the carriage 4 mounted on the base 15 is moved in parallel with the center line of the SPM, and the side 0 head 7a and the side 1 head 7b are positioned on the target track. Further, the rotation of the second gear 18 is transmitted to the first gear 17, the carriage 4 is rotated about the swing center axis P, and the side surface of the carriage 4 abuts the stopper 19a or the stopper 19b so that the azimuth angle is increased. θ is set.

Therefore, by controlling the rotation of the second gear 18 by using one conventional 4 MB FDD magnetic head device, the carriage 4 is set to the initial state S.
The first read / write gap parallel to the center line of PM is rotated to the stopper 19b side to turn the second read / write gap of positive azimuth angle to the second read / write gap.
By rotating the carriage 4 to the stopper 19a side, the third read / write gap having a negative azimuth angle can be easily formed.

Next, the driving method of the first embodiment will be described. Here, the feed pitch in the FD radial direction (normal direction) by the stepping motor 1 is set to 93.75 μm for one track of the screw pitch, and the azimuth angle θ is ± 35.39 with respect to the SPM center line.
Set the stoppers 19a and 19b to the base 15 so that the angle becomes 1 °.
It is arranged on the top.

First, when driving, for example, a 4-megabyte FD, the rotation angle of the second gear 18 is locked in the initial state. At this time, the recording / reproducing gap is parallel to the SPM center line with an offset of 0.35 mm. In this state, a step pulse capable of feeding two tracks in the FD radial direction is applied to the stepping motor 1 to set the base 15 to 93.75 μm × 2 = 1.
By feeding 87.5 μm, the recording medium is positioned on the target track and FD recording / reproduction is performed by the recording / reproducing gap.

Therefore, the conventional F shown in FIGS. 3 and 4 is used.
Similar to the DD, from TK00 to TK79, 80 data widths of 115 μm with a track pitch of 0.1875 mm can be magnetically recorded and reproduced on each side.

Then, in the case of driving the 8 megabyte FD, a step pulse capable of feeding the FD in the radial direction for one track is applied to the stepping motor 1, and the base 15 is fed at a high speed every 93.75 μm. Alternatively, the second gear 18 is rotated in the negative direction (for example, positive on even tracks and negative on odd tracks), and the side surface of the carriage 4 is brought into contact with the stoppers 12a and 12b to end the rotation of the second gear 18. .

At this time, in the FD data format, as shown in FIG. 2, azimuth recording is alternately performed at a track pitch of 93.75 μm and without a guard band at an azimuth angle of ± 35.391 °. On the side 0, the innermost track radius ri is 24.59375 mm and the outermost track radius ro is 39.5 mm. On the side 1, the ri is 2
3.09375 mm, ro is 38 mm, and both sides 0 and 1 are almost the same as those recorded on the conventional 3.5 inch FD (however, only ri is equivalent to one track pitch compared to the conventional one). 93.75 μm shorter). The track width of 93.75 μm in FIG.
The magnetic head has a track width of 115 μm and an azimuth angle θ of COS ⁻¹ (39.75 / 115) = 35.391 ° with respect to the circumferential direction.

Further, in the case where a plurality of tracks are skipped and sent, the rotation of the second gear 18 is stopped while the carriage 4 is moving between the tracks, and the second gear 2 is rotated immediately before the target track. Is also possible.

Therefore, from TK00 to TK159, 160 cylinders on each side can be recorded / reproduced within a conventional track radius at a track pitch of 93.75 μm and without a guard band. That is, the linear recording density is the same as that of the conventional 4-megabyte FDD, the track density is doubled, the maximum storage capacity is doubled, and the 8-megabyte FD can be driven. In addition, the conventional 4 MB FD
Without changing D, track pitch and data width,
Recording / reproduction is performed at a recording density of 34868 BPI or higher without waveform processing.

Here, in the 8-megabyte FD, since data is recorded without prior erasure, a thin magnetic film having a coercive force of 700 to 800 Oe and a layer thickness of 0.5 ± 0.2 μm is used as the magnetic film. Is used.

As described above, according to the first embodiment, the carriage 4 is rotatably mounted on the base 15 about the swing center axis P and defines the azimuth angle θ of the carriage 4. 19a and 19b are arranged on the base 15, first and second gears 17 and 18 for rotating the carriage 4 are provided, and the carriage 4 is SP.
Since the stepping motor 1 for moving in parallel to the M center line is provided, the carriage 4 is rotated about the swing center axis P, and the first read / write is performed by one head in parallel with the FD normal line. The gap and the second and third read / write gaps forming positive and negative azimuth angles with respect to the FD normal can be easily configured, and recording by the first read / write gap parallel to the FD normal can be performed. , And azimuth recording with the second and third read / write gaps.

Further, the conventional magnetic head of 4 Mbyte FDD can be used without producing a special magnetic head for 8 Mbyte FDD, and the cost can be reduced.

Further, the azimuth angles of two adjacent tracks are ± 3 which are positive and negative equal amounts with respect to the circumferential direction of the FD.
Since it is 5.391 °, the angle formed by these two data patterns is about 109 °, and even if the magnetic head that read TKn reads off the track, the adjacent data (TKn-1, TKn + 1) It cannot be read because the azimuth loss is large.

Further, since the guard band in azimuth recording can be eliminated, the linear recording density can be made equal to that of 4 megabyte FDD, the track density can be doubled, and the maximum storage capacity can be doubled without shortening the recording wavelength. And can
A conventional 4 megabyte FDD magnetic head can be used to obtain a backward compatible 8 megabyte FDD.

Further, in the case of the 8-megabyte FD, since the azimuth recording system is adopted, the magnetic film of the medium can be made thin and the cost of the FD can be reduced.

In the case of 8 megabyte FD, recording / reproduction is performed by the second and third read / write gaps of positive and negative azimuth angles, and F of 4 megabytes or less is used.
In the case of D, since recording / reproducing is performed by the first read / write gap, it is possible to drive 8 MB and 4 MB without changing the track pitch or data width and without wavelength processing. , Can be fully backward compatible.

Example 2. In the first embodiment, the carriage 4 to which one magnetic head is attached is rotated to move the first read / write gap parallel to the FD normal line and the second and third read / write gaps having positive and negative azimuth angles. Although the read / write gap is constituted, in the second embodiment, a magnetic head having a read / write gap parallel to the FD normal line and a read / write gap having positive and negative azimuth angles are provided. A magnetic head and a switch for generating a magnetic field in the read / write gap having a positive (or negative) azimuth angle when the magnetic head moves to a track that requires a positive (or negative) azimuth angle, Has the same effect.

Example 3. In the second embodiment, a magnetic head having a read / write gap parallel to the FD normal and a magnetic head having a positive / negative azimuth angle read / write gap are provided. In No. 3, a magnetic head having a read / write gap parallel to the FD normal, a magnetic head having a positive azimuth angle read / write gap, and a magnetic head having a negative azimuth angle read / write gap. The same effect is achieved.

Example 4. In the first embodiment, two types (93.75 μm, 187.
Although the track pitch of 5 μm) is sent, in the fourth embodiment, the same effect can be obtained even if the stepping motor sending the track pitch of 93.75 μm and the stepping motor sending the track pitch of 187.5 μm are provided. Play.

Example 5. In the first embodiment, the screw pitch is configured so that one track can feed 93.75 μm, but in the fifth embodiment, the screw pitch is such that one track can feed 187.5 μm, and 1/2
The same effect can be obtained by controlling so that only the track can be sent.

Example 6. In the first embodiment described above, the first and second gears 17 and 18 are used as the swinging means of the carriage 4, but in the sixth embodiment, the swing center shaft 22 is rotated as shown in FIG. Let me move the bar 2
It is assumed that 0 and 21 are swung about the swing center Q to set the azimuth angle of the magnetic head, and the same effect is obtained.

In each of the above embodiments, the needle moving means for moving the head in parallel with the normal line of the FD is a needle.
Although the screw method is used, the same effect can be obtained with the spiral cam method and the steel belt method.

[0045]

Since the present invention is constituted as described above, it has the following effects.

In the floppy disk drive device according to the first aspect of the present invention, the first read / write gap parallel to the normal line of the floppy disk and the second read / write gap forming a positive azimuth angle with respect to the normal line of the floppy disk are provided. One or more heads having a read / write gap and a third read / write gap forming a negative azimuth angle with respect to the normal line of the floppy disk, and head moving means for moving the head parallel to the normal line of the floppy disk. Since it is equipped with
The recording by the read / write gap and the azimuth recording by the second and third read / write gaps can be easily performed, and an inexpensive and high-capacity FDD can be obtained.

The driving method of the floppy disk drive device according to the second invention of the present invention is the first read / write gap parallel to the normal line of the floppy disk.
One or more heads having a second read / write gap having a positive azimuth angle with respect to the normal of the floppy disk and a third read / write gap having a negative azimuth angle with respect to the normal of the floppy disk; , A head moving means for moving the head parallel to the normal line of the floppy disk, and the storage capacity of the floppy disk is 8
In the case of megabyte, the head is moved by the head moving means to alternately switch the second and third read / write gaps for recording / reproduction, and when the storage capacity of the floppy disk is 4 megabytes or less, Since the head is moved by the moving means and recording / reproducing is performed by the first read / write gap, it is possible to drive the 8 megabyte FD without changing the track pitch or the data width and without performing the waveform processing. Compatibility can be ensured.

[Brief description of drawings]

1A and 1B are respectively a first embodiment of the present invention.
FIG. 3 is a plan view and a side view of a main part of the floppy disk drive device showing FIG.

FIG. 2 is a schematic diagram showing a data format by the floppy disk drive device according to the first embodiment of the present invention.

FIG. 3 shows a needle in a conventional head positioning mechanism.
It is an external view showing a screw method.

FIG. 4 is a schematic cross-sectional view of a magnetic head portion in a conventional floppy disk drive device.

FIG. 5 is a schematic diagram showing a side 0 data format in a conventional floppy disk.

FIG. 6 is a schematic diagram showing a side 1 data format in a conventional floppy disk.

FIG. 7 is a schematic diagram showing a positional relationship between a gap of a magnetic head and a floppy disk in a conventional floppy disk drive device.

8A and 8B are schematic diagrams showing tape formats of a VHS system and a β system in a conventional VTR, respectively.

9A and 9B are a perspective view of a magnetic recording / reproducing mechanism section in a conventional magnetic recording device and an explanatory view showing a recording process.

FIG. 10 is a plan view of a carriage swing mechanism of a floppy disk drive device showing Embodiment 6 of the present invention.

[Explanation of symbols]

 1 stepping motor (head moving means) 2 screw (head moving means) 3 needle (head moving means) 4 carriage 5 screw presser (head moving means) 7a side 0 head 7b side 1 head 9a, 9b core 10 floppy disk

[Procedure amendment]

[Submission date] February 16, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0037

[Correction method] Delete

Claims (2)

[Claims] 1. A first parallel to a normal line of a floppy disk.
Read / write gap, a second read / write gap having a positive azimuth angle with respect to the normal line of the floppy disk, and a third read / write gap having a negative azimuth angle with respect to the normal line of the floppy disk. A floppy disk drive device comprising one or more heads having the head and a head moving means for moving the head parallel to a normal line of the floppy disk. 2. The first parallel to the normal of the floppy disk
Read / write gap, a second read / write gap having a positive azimuth angle with respect to the normal line of the floppy disk, and a third read / write gap having a negative azimuth angle with respect to the normal line of the floppy disk. And a head moving means for moving the head parallel to the normal line of the floppy disk. When the storage capacity of the floppy disk is 8 megabytes, the head moving means is used to When the head is moved, the second and third read / write gaps are alternately switched for recording and reproduction, and when the storage capacity of the floppy disk is 4 megabytes or less, the head is moved by the head moving means. Recording / reproducing by the first read / write gap. The driving method of the floppy disk drive.