EP0110050A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Disc drive for flexible discs with different track widths
Assignee: Mitsubishi Electric Corp
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Filing: 1983-09-27
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Granted: —
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Expires: 2003-09-27
Abstract
Abstract A flexible disc device includes a magnetic head for reading data written on a flexible disc medium or writing data to the medium. The head selects its effective track width as defined by the core width of the read/write head gap (22) and the erase head gaps (24a, 24b) to correspond with the record density of the disc. Thus flexible disc media with different track densities are made compatible.
Inventors
- 👤 Shin C/O Mitsubishi Denki K. K. Isozaki
- 👤 Masaru C/O Mitsubishi Denki K. K. Sasaki
- 👤 Shuroku C/O Mitsubishi Denki K. K. Hosaka
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 20:56
CPC Classifications
G; G11; G11B; G11B19/00; G11B19/02; G11B19/12; G11B19/128; G11B5/00; G11B5/012; G11B5/016; G11B5/127; G11B5/265; G11B5/2652; G11B5/2654; G11B5/2655
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
207 words
A flexible disc device having a writing/reading magnetic head for reading and writing a flexible disc medium, said device comprising: a) A spindle motor for rotating the disc medium at a prescribed constant rotating speed, said spindle motor being determined in the rotating speed by a spindle motor drive circuit; b) magnetic head transfer means for moving the magnetic head so that the magnetic head is positioned with respect to any track of the flexible disc medium; c) track density discrimination means for discriminating the track density of the flexible disc medium installed within the device body; d) said magnetic head being enable to change effective track width specified at least by total amount of core width of writing/reading head gap and core width of erasing head gap at the writing state corresponding to the record density in the diameter direction of the flexible disc medium installed within the body; and e) means for changing the effective track width of the magnetic head, said changing means being driven corresponding to the discrimination signal from the track density discrimination means, thereby data compatibility in both directions of reading and writing by the magnetic head being given regarding at least two flexible disc media different in the track density.
Claim 2
Dependent Claim
207 words
A flexible disc device having a writing/reading magnetic head for reading and writing a flexible disc medium, said device comprising: a) A spindle motor for rotating the disc medium at a prescribed constant rotating speed, said spindle motor being determined in the rotating speed by a spindle motor drive circuit; b) magnetic head transfer means for moving the magnetic head so that the magnetic head is positioned with respect to any track of the flexible disc medium; c) track density discrimination means for discriminating the track density of the flexible disc medium installed within the device body; d) said magnetic head being enable to change effective track width specified at least by total amount of core width of writing/reading head gap and core width of erasing head gap at the writing state corresponding to the record density in the diameter direction of the flexible disc medium installed within the body; and e) means for changing the effective track width of the magnetic head, said changing means being driven corresponding to the discrimination signal from the track density discrimination means, thereby data compatibility in both directions of reading and writing by the magnetic head being given regarding at least two flexible disc media different in the track density.
Claim 3
Dependent Claim
43 words
A flexible disc device as set forth in claim 1, wherein said magnetic head is provided with a core having erasing head gaps at both sides of a core having erasing head gaps at both sides of a core having record regenerative head.
Claim 4
Dependent Claim
44 words
A flexible disc device as set forth in claim 2, wherein the cores having the erasing head gaps comprises two pairs of erasing head gaps, and the cores of two pairs of erasing head gaps are provided with first and second erasing coils respectively.
Claim 5
Dependent Claim
42 words
A flexible disc device as set forth in claim 3, wherein said first and second erasing coils are supplied selectively with erasing current by the changing means corresponding to the discrimination signal, and effective track width of the magnetic head is changed.
Claim 6
Dependent Claim
26 words
A flexible disc device as set forth in claim 3, wherein said second erasing coil is wound on cores of two pairs of erasing head gaps.
Claim 7
Dependent Claim
61 words
A flexible disc device as set forth in claim 1, wherein total amount of core width of record regenerative head gap and core width of a pair of erasing head gaps being adjacent the former core is made nearly equal to the track width having maximum record density in the diameter direction of the flexible disc medium installed within the body.
Claim 8
Dependent Claim
33 words
A flexible disc device as set forth in claim 6, wherein total core width of the writing/reading head gap and all erasing head gaps is made multiple in integer of said total amount.
Claim 9
Dependent Claim
41 words
A flexible disc device as set forth in claim 1, wherein said magnetic head transfer means is composed of a step motor, and the step motor is driven per one pulse of the step input signal for positioning the magnetic head.
Claim 10
Dependent Claim
40 words
A flexible disc device as set forth in claim 8, wherein the pulse number of step pulse input signal supplied to the step motor is increased in multiple of integer by the discrimination signal from the track density discrimination means.
Claim 11
Dependent Claim
32 words
A flexible disc device as set forth in claim 9, wherein increase of the pulse number of step pulse input signal occurs when the track density of the flexible disc is low.
Claim 12
Dependent Claim
50 words
A flexible disc device as set_forth in claim 1, wherein said track density discrimination means is constituted by a notch or a hole formed on a jacket of the flexible disc medium corresponding to the track density, and a detector for detecting the notch or the hole optically or mechanically.
Claim 13
Dependent Claim
45 words
A flexible disc device as set forth in claim 1, wherein said track density discriminating means comprises means for reading content of data already recorded on the flexible disc medium, and interpreting the content of data or deciding whether the reading is true or false.
Claim 14
Dependent Claim
27 words
A flexible disc device as set forth in claim 12, wherein said deciding means is executed by a host computer and the discrimination signal is sent out.
Claim 15
Dependent Claim
35 words
A flexible disc device as set forth in claim 1, wherein the rotating speed of the spindle motor is varied into other constant-speed rotation corresponding to the discrimination signal from the track density discrimination means.
Claim 16
Dependent Claim
62 words
A magnetic head assembly which is suitable for a flexible disc device, wherein effective width specified by total amount of core width of writing/reading head gap and core width of erasing head gap of the magnetic head is changed to the medium being different in the record density .in the diameter direction of the flexible disc medium installed within the device body.
Claim 17
Dependent Claim
62 words
A magnetic head assembly which is suitable for a flexible disc device, wherein effective width specified by total amount of core width of writing/reading head gap and core width of erasing head gap of the magnetic head is changed to the medium being different in the record density .in the diameter direction of the flexible disc medium installed within the device body.
Claim 18
Dependent Claim
50 words
A magnetic head assembly as set forth in claim 15, wherein two pairs of erasing head gaps are provided on both sides of the writing/reading head core, erase effective width is changed electrically corresponding to whether one pair of gaps at inner side are energized or two pairs are energized.
Claim 19
Dependent Claim
35 words
A magnetic head assembly as set forth in claim 15, wherein the magnetic head assembly is composed of a core having writing/readin g head gap and a core having two pairs of erasing head gaps.
Claim 20
Dependent Claim
28 words
A magnetic head assembly as set forth in claim 17, wherein the core of two pairs of erasing head gaps is provided with first and second erasing coils.
Claim 21
Dependent Claim
35 words
A magnetic head assembly as set forth in claim 17, wherein two pairs of erasing head gaps are shifted so that a pair of inner gaps and a pair of outer gaps are not aligned.
Claim 22
Dependent Claim
25 words
A magnetic head assembly as set forth in claim 19, wherein two pairs of the erasing head gaps are shifted by 0.2 mm or more.
Claim 23
Dependent Claim
89 words
A magnetic head assembly as set forth in claim 17, wherein the writing/reading head core having the writing/reading head gap is provided with a record regenerative coil and a closing core adhered thereto, a first erasing head core is provided with an erasing coil on a leg at higher position and a closing core adhered thereto, a second erasing core is provided with an erasing coil on a leg at lower position and a closing coil adhered thereto, and these cores are grasped by slide shoes through non-magnetic spacers.
References Cited (Backward Citations)
US3353168A
Cited
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