US4958248A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reflective tachometer/headwheel assembly for a rotary head scanner
Assignee: Datatape Inc
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Filing: 1988-12-19
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Granted: 1990-09-18
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Expires: 2008-12-19
Abstract
Abstract For use in a helical scan magnetic tape record/reproduce apparatus, disclosed is a rotary head scanner including a reflective tachometer/headwheel assembly. The rotary head scanner includes a plurality of magnetic record/reproduce heads mounted on a headwheel which has a reflective tachometer disposed on one side of the headwheel. A radiation source and radiation sensor are located adjacent to the reflective tachometer. The radiation sensor senses radiation reflected from the tachometer and produces a signal which is a function of the rotational position and/or rotational speed of the headwheel.
Inventors
- 👤 Milan V. Trcka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:41
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/18; G11B15/46; G11B15/467; G11B15/473; G11B15/4731; G01; G01P; G01P13/00; G01P13/02; G01P13/04; G01P13/045; G01P3/00; G01P3/42; G01P3/44; G01P3/48; G01P3/481; G01P3/486; G11B5/00; G11B5/48; G11B5/52; G11B5/53
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
112 words
Rotary magnetic head scanner apparatus, comprising: a headwheel mounted for rotation about a rotational axis; wherein said headwheel has an annular slot on one side thereof; at least one magnetic head assembly mounted on the periphery of said headwheel; an annular reflective tachometer mounted in said annular slot on said one side of said headwheel; and a radiation source and a radiation sensor mounted on said one side of said headwheel, adjacent to said reflective which is reflected from said reflective tachometer to said radiation sensor, and wherein said sensor develops a signal, in response thereto, which is a function of the rotational position and/or rotational speed of said rotating magnetic heads.
Claim 2
Dependent Claim
112 words
Rotary magnetic head scanner apparatus, comprising: a headwheel mounted for rotation about a rotational axis; wherein said headwheel has an annular slot on one side thereof; at least one magnetic head assembly mounted on the periphery of said headwheel; an annular reflective tachometer mounted in said annular slot on said one side of said headwheel; and a radiation source and a radiation sensor mounted on said one side of said headwheel, adjacent to said reflective which is reflected from said reflective tachometer to said radiation sensor, and wherein said sensor develops a signal, in response thereto, which is a function of the rotational position and/or rotational speed of said rotating magnetic heads.
Claim 3
Dependent Claim
30 words
The apparatus of claim 1 wherein said headwheel annular slot and said annular tachometer are dimensioned such that a thermal expansion gap is provided between said headwheel and said tachometer.
Claim 4
Dependent Claim
31 words
The apparatus of claim 1 including radiation reflecting means for reflecting radiation from said radiation source to said tachometer and for reflecting radiation reflected from said tachometer to said radiation sensor.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-09-17 | 1994-03-19 | 1994-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-17 | 1998-03-19 | 1998-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-09-17 | 2002-03-19 | 2002-09-18 | $7700.00 | Window Closed / Lapsed |