Patent US4912582A successfully refreshed from Google Patents.
US4912582A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Floppy disk drive system with improved record/playback heads
Assignee: Seiko Epson Corp
•
Filing: 1988-11-21
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Granted: 1990-03-27
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Expires: 2008-11-21
Abstract
Abstract A floppy disk drive system for double-sided recording and playback having first and second heads positioned to hold a disk therebetween is provided. The first and second heads each have a read/write gap and each have a contacting plane for contacting the disk. Each such contacting plane has an inner edge position toward the center of the disk and an outer edge positioned toward the outer circumference of the disk. The gap of the first head is closer to the outer circumference of the disk than the gap of the second head when the heads are assembled in facing relation. The distance between the center of the inner edge of the contacting plane of the first head and the center of the read/write gap of the second head is about 0.6 mm or less. The contacting plane of the second head may be larger than that of the first head, said enlargement being in the direction of the inner circumference of the disk. At least one of the heads may have the two inner corners thereof chamfered by about C 0.5 or more and the corresponding corners of the contacting plane may be smoothly rounded. The contacting plane of the first head may be larger than that of the second head, said enlargement being in the direction of the outer circumference of the disk.
Inventors
- 👤 Akihiro Gomi
- 👤 Shin Shibata
- 👤 Misuo Oguchi
- 👤 Sumio Gomi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:06
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/488; G11B5/4886; G11B17/00; G11B17/32; G11B5/10
Claims Analysis
Total Claims: 46
Claim 1
Independent Claim
218 words
A floppy disk drive system for double-sided recording and playback comprising a first and a second head positioned to receive a disk therebetween; said first and second head each having a read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk with a flat portion therebetween including the gap, the inner edge of said second head extending closer to the center of the disk than said inner edge of said first head; the gap of said first head being closer to the outer circumference of the disk than the gap of the second head and each gap opposing the flat portion of the other head across the disk when the heads are assembled in facing relation; and the distance measured along a radius of the disk between the inner edge of the contacting plane of the first head and the center of the read/write gap of said second head being 0.6mm or less; whereby intimate contact between the disk and the second head is maintained even where there is movement of the heads relative to the disk in a direction higher than the proper position for holding the disk.
Claim 2
Dependent Claim
218 words
A floppy disk drive system for double-sided recording and playback comprising a first and a second head positioned to receive a disk therebetween; said first and second head each having a read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk with a flat portion therebetween including the gap, the inner edge of said second head extending closer to the center of the disk than said inner edge of said first head; the gap of said first head being closer to the outer circumference of the disk than the gap of the second head and each gap opposing the flat portion of the other head across the disk when the heads are assembled in facing relation; and the distance measured along a radius of the disk between the inner edge of the contacting plane of the first head and the center of the read/write gap of said second head being 0.6mm or less; whereby intimate contact between the disk and the second head is maintained even where there is movement of the heads relative to the disk in a direction higher than the proper position for holding the disk.
Claim 3
Dependent Claim
86 words
The floppy disk drive system of claim 1, wherein the contacting planes of the first and second heads overlap in a central region including the read/write gaps thereof, the contacting plane of the second head extending beyond the central overlapping region in the direction along a radius of the disk toward the inner circumference of the disk, the contacting plane of the first head extending beyond the central overlapping region in the direction along a radius of the disk toward the outer circumference of the disk.
Claim 4
Dependent Claim
32 words
The floppy disk drive system of claim 2, wherein said rectangular magnetic heads on the side thereof disposed toward the center of the disk are chamfered by about C 0.5 or more.
Claim 5
Dependent Claim
27 words
The floppy disk drive system of claim 3, wherein all four corners or each of said magnetic heads have been chamfered by about C 0.5 or more.
Claim 6
Dependent Claim
24 words
The floppy disk drive system of claim 2, wherein said first head is the lower head and said second head is the upper head.
Claim 7
Dependent Claim
94 words
The floppy disk drive system of claim 2, wherein the distance between the respective inner edges of the contacting planes of the first and second heads, measured in the direction along a radius of the disk toward the inner circumference of the disk, is about 0.5 mm to about 1.5 mm, and the distance between the respective outer edges of the contacting planes of the first and second heads, measured in the direction along a radius of the disk toward the inner circumference of the disk, is about 0.5 mm to about 1.5 mm.
Claim 8
Dependent Claim
47 words
The floppy disk drive system of claim 1, wherein at least one of said heads is substantially rectangular and at least two corners of the rectangular magnetic head on the side thereof disposed toward the center of the disk is chamfered by about C 0.5 or more.
Claim 9
Dependent Claim
26 words
The floppy disk drive system of claim 7, wherein all four corners of said rectangular magnetic head have been chamfered by about C 0.5 or more.
Claim 10
Dependent Claim
24 words
The floppy disk drive system of claim 1, wherein said first head is the lower head and said second head is the upper head.
Claim 11
Dependent Claim
246 words
A floppy disk drive system for doublesided recording and playback comprising a first and a second head positioned to receive a disk therebetween; said first and second head each having a read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk with a flat portion therebetween including the gap, the contacting plane of the second head being larger than that of the first head, the enlargement of said contacting plane of the second head, in relation to the contacting plane of the first head, being in the direction along a radius of the disk toward the inner circumference of the disk; the gap of said first head being closer to the outer circumference of the disk than the gap of the second head and each gap opposing the flat portion of the other head across the disk when the heads are assembled in facing relation; and the distance measured along a radius of the disk between the inner edge of the contacting plane of the first head and the center of the read/write gap of said second head being 0.6mm or less; whereby intimate contact between the disk and the second head is maintained even where is movement of the heads relative to the disk in a direction higher than the proper position for holding the disk.
Claim 12
Dependent Claim
246 words
A floppy disk drive system for doublesided recording and playback comprising a first and a second head positioned to receive a disk therebetween; said first and second head each having a read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk with a flat portion therebetween including the gap, the contacting plane of the second head being larger than that of the first head, the enlargement of said contacting plane of the second head, in relation to the contacting plane of the first head, being in the direction along a radius of the disk toward the inner circumference of the disk; the gap of said first head being closer to the outer circumference of the disk than the gap of the second head and each gap opposing the flat portion of the other head across the disk when the heads are assembled in facing relation; and the distance measured along a radius of the disk between the inner edge of the contacting plane of the first head and the center of the read/write gap of said second head being 0.6mm or less; whereby intimate contact between the disk and the second head is maintained even where is movement of the heads relative to the disk in a direction higher than the proper position for holding the disk.
Claim 13
Dependent Claim
60 words
The floppy disk drive system of claim 10, wherein the distance between the inner edge of the contacting plane of the second head and the inner edge of the contacting plane of the first head, measured in the direction along a radius of the disk toward the inner circumference of the disk, is about 0.5 mm to about 1.5 mm.
Claim 14
Dependent Claim
45 words
The floppy disk drive system of claim 10, wherein said heads are substantially rectangular and at least two corners of each of the rectangular magnetic heads on the side thereof disposed toward the center of the disk are chamfered by about C 0.5 or more.
Claim 15
Dependent Claim
26 words
The floppy disk drive system of claim 12, wherein all four corners of each of said heads have been chamfered by about C 0.5 or more.
Claim 16
Dependent Claim
24 words
The floppy disk drive system of claim 10, wherein said first head is the lower head and said second head is the upper head.
Claim 17
Dependent Claim
247 words
A floppy disk drive system for double-sided recording and playback comprising a first and a second head positioned to receive a disk therebetween; said first and second head each having a read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk with a flat portion therebetween including the gap, the contacting plane of the first head being larger than that of the second head, the enlargement of said contacting plane of the first head, in relation to the contacting plane of the second head, being in the direction along a radius of the disk toward the outer circumference of the disk; the gap of said first head being closer to the outer circumference of the disk than the gap of the second head and each gap opposing the flat portion of the other head across the disk when the heads are assembled in facing relation; and the distance measured along a radius of the disk between the inner edge of the contacting plane of the first head and the center or the read/write gap of said second head being 0.6mm or less; whereby intimate contact between the disk and the second head is maintained even where there is movement of the heads relative to the disk in a direction higher than the proper position for holding the disk.
Claim 18
Dependent Claim
247 words
A floppy disk drive system for double-sided recording and playback comprising a first and a second head positioned to receive a disk therebetween; said first and second head each having a read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk with a flat portion therebetween including the gap, the contacting plane of the first head being larger than that of the second head, the enlargement of said contacting plane of the first head, in relation to the contacting plane of the second head, being in the direction along a radius of the disk toward the outer circumference of the disk; the gap of said first head being closer to the outer circumference of the disk than the gap of the second head and each gap opposing the flat portion of the other head across the disk when the heads are assembled in facing relation; and the distance measured along a radius of the disk between the inner edge of the contacting plane of the first head and the center or the read/write gap of said second head being 0.6mm or less; whereby intimate contact between the disk and the second head is maintained even where there is movement of the heads relative to the disk in a direction higher than the proper position for holding the disk.
Claim 19
Dependent Claim
60 words
The floppy disk drive system of claim 15, wherein the distance between the outer edge of the contacting plane of the second head and the outer edge of the contacting plane of the first head, measured in the direction along a radius of the disk toward the outer circumference of the disk, is about 0.5 mm to about 1.5 mm.
Claim 20
Dependent Claim
45 words
The floppy disk drive system of claim 15, wherein said heads are substantially rectangular and at least two corners of each of the rectangular magnetic heads on the side thereof disposed toward the center of the disk are chamfered by about C 0.5 or more.
Claim 21
Dependent Claim
27 words
The floppy disk drive system of claim 17, wherein all four corners of each of said magnetic heads have been chamfered by about C 0.5 or more.
Claim 22
Dependent Claim
24 words
The floppy disk drive system of claim 6, wherein said first head is the lower head and said second head is the upper head.
Claim 23
Dependent Claim
207 words
A floppy disk drive system for double-sided recording and playback comprising a first head and a second head positioned to receive a disk therebetween; said first and second heads each having a read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk; the gap of the first head being closer to the outer circumference of the disk than the gap of the second head when the heads are assembled in facing relation; and the inner edge of the contacting plane of said second head extending inward a distance of about 0.5mm to 1.5mm in the direction along a radius of the disk toward the inner circumference of the disk, beyond the inner edge of the first head when the heads are assembled in facing relation the inner edge of the first head being offset from the inner edge of the second head; whereby intimate contact between the disk and the second head is maintained even when there is movement of the heads relative to the disk in a direction lower than the proper position for holding the disk.
Claim 24
Dependent Claim
207 words
A floppy disk drive system for double-sided recording and playback comprising a first head and a second head positioned to receive a disk therebetween; said first and second heads each having a read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk; the gap of the first head being closer to the outer circumference of the disk than the gap of the second head when the heads are assembled in facing relation; and the inner edge of the contacting plane of said second head extending inward a distance of about 0.5mm to 1.5mm in the direction along a radius of the disk toward the inner circumference of the disk, beyond the inner edge of the first head when the heads are assembled in facing relation the inner edge of the first head being offset from the inner edge of the second head; whereby intimate contact between the disk and the second head is maintained even when there is movement of the heads relative to the disk in a direction lower than the proper position for holding the disk.
Claim 25
Dependent Claim
45 words
The floppy disk drive system of claim 20, wherein said heads are substantially rectangular and at least two corners of each of the rectangular magnetic heads on the side thereof disposed toward the center of the disk are chamfered by about C 0.5 or more.
Claim 26
Dependent Claim
27 words
The floppy disk drive system of claim 21, wherein all four corners of each of said magnetic heads have been chamfered by about C 0.5 or more.
Claim 27
Dependent Claim
24 words
The floppy disk drive system of claim 21, wherein said first head is the lower head and said second head is the upper head.
Claim 28
Dependent Claim
51 words
The floppy disk drive system comprising a substantially rectangular magnetic head having a contacting plane for contacting a disk wherein at least the two corners of the rectangular magnetic head which are on the side thereof disposed toward the center of the disk, are chamfered by about C 0.5 or more.
Claim 29
Dependent Claim
51 words
The floppy disk drive system comprising a substantially rectangular magnetic head having a contacting plane for contacting a disk wherein at least the two corners of the rectangular magnetic head which are on the side thereof disposed toward the center of the disk, are chamfered by about C 0.5 or more.
Claim 30
Dependent Claim
25 words
The floppy disk drive system of claim 24, wherein all four corners of the rectangular magnetic head are chamfered by about C 0.5 or more.
Claim 31
Dependent Claim
50 words
The floppy disk drive system of claim 25, further comprising a second substantially rectangular magnetic head having a contacting plane for contacting a disk in facing relation to said first-mentioned head, wherein the four corners of the second substantially rectangular magnetic head are chamfered by about C 0.5 or more.
Claim 32
Dependent Claim
31 words
The floppy disk drive system according to claim 26, wherein the corners of the contacting plane of said two heads, corresponding to the chamfered corners of the head, are smoothly rounded.
Claim 33
Dependent Claim
27 words
The floppy disk drive system according to claim 25, wherein the corners of the contacting plane, corresponding to the chamfered corners of the head, are smoothly rounded.
Claim 34
Dependent Claim
62 words
The floppy disk drive system of claim 24, further comprising a second rectangular magnetic head having a contacting plane for contacting a disk in facing relation to said first-mentioned head, wherein at least 2 corners of the second rectangular magnetic head, which are on the side thereof disposed toward the center of the disk, are chamfered by about C 0.5 or more.
Claim 35
Dependent Claim
31 words
The floppy disk drive system according to claim 29, wherein the corners of the contacting plane of said two heads, corresponding to the chamfered corners of the head, are smoothly rounded.
Claim 36
Dependent Claim
27 words
The floppy disk drive system according to claim 24, wherein the corners of the contacting plane, corresponding to the chamfered corners of the head, are smoothly rounded.
Claim 37
Dependent Claim
187 words
A floppy disk system for double-sided recording and playback comprising a first head and a second head positioned to receive a disk therebetween; said first and second head each having read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk; the gap of said first head being closer to the outer circumference of the disk than the gap of the second head; and the outer edge of the contacting plane of the first head extending outwardly beyond the outer edge of the second head a distance of about 0.5 mm to 1.5 mm in the direction along a radius of the disk toward the outer circumference of the disk when the heads are in facing relation and the outer edge of the first head is offset from the outer edge of the second head; whereby intimate contact between the disk and the first head is maintained even when there is movement of the head relative to the disk.
Claim 38
Dependent Claim
187 words
A floppy disk system for double-sided recording and playback comprising a first head and a second head positioned to receive a disk therebetween; said first and second head each having read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk; the gap of said first head being closer to the outer circumference of the disk than the gap of the second head; and the outer edge of the contacting plane of the first head extending outwardly beyond the outer edge of the second head a distance of about 0.5 mm to 1.5 mm in the direction along a radius of the disk toward the outer circumference of the disk when the heads are in facing relation and the outer edge of the first head is offset from the outer edge of the second head; whereby intimate contact between the disk and the first head is maintained even when there is movement of the head relative to the disk.
Claim 39
Dependent Claim
45 words
The floppy disk drive system of claim 32, wherein said heads are substantially rectangular and at least two corners or each of the rectangular magnetic heads on the side thereof disposed toward the center of the disk are chamfered by about C 0.5 or more.
Claim 40
Dependent Claim
27 words
The floppy disk drive system of claim 33, wherein all four corners of each of said magnetic heads have been chamfered by about C 0.5 or more.
Claim 41
Dependent Claim
24 words
The floppy disk drive system of claim 32, wherein said first head is the lower head and said second head is the upper head.
Claim 42
Dependent Claim
242 words
A floppy disk drive system for double-sized recording and playback comprising a first and a second head positioned to receive a disk therebetween; said first and second heads each having a read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk; the gap of said first head being closer to the outer circumference of the disk than the gap of the second head and the outer edge of the second head being offset from the outer edge of the first head when the heads are assembled in facing relation; and wherein the contacting planes of the first and second heads overlap in a central region including the read/write gaps thereof, the contacting plane of the second head extending beyond the central overlapping region a distance of about 0.5 mm to about 1.5 mm in the direction along a radius of the disk toward the inner circumference of the disk, the contacting plane of the first head extending beyond the central overlapping region a distance of about 0.5 mm to about 1.5 mm in the direction along a radius of the disk toward the outer circumference of the disk even when there is movement of the first head in a direction higher or a direction lower than the proper position for holding the disk.
Claim 43
Dependent Claim
242 words
A floppy disk drive system for double-sized recording and playback comprising a first and a second head positioned to receive a disk therebetween; said first and second heads each having a read/write gap and each having a contacting plane for contacting the disk, each such contacting plane having an inner edge positioned toward the center of the disk and an outer edge positioned toward the outer circumference of the disk; the gap of said first head being closer to the outer circumference of the disk than the gap of the second head and the outer edge of the second head being offset from the outer edge of the first head when the heads are assembled in facing relation; and wherein the contacting planes of the first and second heads overlap in a central region including the read/write gaps thereof, the contacting plane of the second head extending beyond the central overlapping region a distance of about 0.5 mm to about 1.5 mm in the direction along a radius of the disk toward the inner circumference of the disk, the contacting plane of the first head extending beyond the central overlapping region a distance of about 0.5 mm to about 1.5 mm in the direction along a radius of the disk toward the outer circumference of the disk even when there is movement of the first head in a direction higher or a direction lower than the proper position for holding the disk.
Claim 44
Dependent Claim
45 words
The floppy disk drive system of claim 36, wherein said heads are substantially rectangular and at least two corners of each of the rectangular magnetic heads on the side thereof disposed toward the center of the disk are chamfered by about C 0.5 or more.
Claim 45
Dependent Claim
27 words
The floppy disk drive system of claim 37, wherein all four corners of each of said magnetic head have been chamfered by about C 0.5 or more.
Claim 46
Dependent Claim
24 words
The floppy disk drive system of claim 36, wherein said first head is the lower head and said second head is the upper head.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-03-26 | 1993-09-25 | 1994-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-26 | 1997-09-25 | 1998-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-26 | 2001-09-25 | 2002-03-27 | $7700.00 | Window Closed / Lapsed |