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US4524400A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic transducer positioning apparatus

Assignee: Individual
•
Filing: 1983-02-01
•
Granted: 1985-06-18
•
Expires: 2003-02-01
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Abstract

Abstract A movable carriage carrying magnetic transducer head is positioned at predetermined points adjacent a floppy disc surface for appropriate reading/writing of data thereon. The transducers are positioned by a permanent magnet stepping motor which rotates a cam shaft. The cam surfaces on the shaft drive a plurality of balls into engagement with opposed racks defining "V"-shaped notches of different pitches formed on a surface of the carriage and on a fixed surface adjacent thereto. As the balls sequentially enter the "V"-shaped notches, they force individual pairs thereof into alignment, the carriage and thus the transducer means are sequentially and discretely positioned at predetermined data track positions on the floppy disc.

Inventors

  • 👤 Gill Cantwell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 02:37
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/54; G11B5/55; G11B5/5521

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 145 words
Magnetic transducer positioning apparatus comprising: (a) a carriage carrying magnetic transducer means; (b) means for applying a force to said carriage to move said carriage to a predetermined position including: (1) a first member having a first plurality of force receiving surfaces of a first predetermined spacing; (2) a second member disposed adjacent said first member and having a second plurality of force receiving surfaces of a second predetermined spacing, said second predetermined spacing being different from said first predetermined spacing; (3) a driving means disposed adjacent said first and second members; (4) means for moving said driving means into simultaneous engagement with said first and second surfaces for aligning at least one of said second surfaces with one of said first surfaces; and (5) one of said first and second members being substantially fixed relative to the other of said first and second members.
Claim 2
Dependent Claim 145 words
Magnetic transducer positioning apparatus comprising: (a) a carriage carrying magnetic transducer means; (b) means for applying a force to said carriage to move said carriage to a predetermined position including: (1) a first member having a first plurality of force receiving surfaces of a first predetermined spacing; (2) a second member disposed adjacent said first member and having a second plurality of force receiving surfaces of a second predetermined spacing, said second predetermined spacing being different from said first predetermined spacing; (3) a driving means disposed adjacent said first and second members; (4) means for moving said driving means into simultaneous engagement with said first and second surfaces for aligning at least one of said second surfaces with one of said first surfaces; and (5) one of said first and second members being substantially fixed relative to the other of said first and second members.
Claim 3
Dependent Claim 27 words
Magnetic transducer positioning apparatus as defined in claim 1 wherein said driving means includes a separate driving member for each of said surfaces on said first member.
Claim 4
Dependent Claim 35 words
Magnetic transducer apparatus as defined in claim 2 wherein each of said driving members defines a curved surface and said force receiving surfaces on said first and second members are depressions defined by angular walls.
Claim 5
Dependent Claim 15 words
Magnetic transducer positioning apparatus as defined in claim 3 wherein said driving members are balls.
Claim 6
Dependent Claim 15 words
Magnetic transducer positioning apparatus as defined in claim 4 wherein said walls define flat surfaces.
Claim 7
Dependent Claim 20 words
Magentic transducer positioning apparatus as defined in claim 5 wherein each of said force receiving surfaces is a "V"-shaped notch.
Claim 8
Dependent Claim 21 words
Magnetic transducer positioning apparatus as defined in claim 2 wherein said means for moving said driving members is a cam means.
Claim 9
Dependent Claim 28 words
Magnetic transducer positioning apparatus as defined in claim 7 wherein said cam means is an elongated molded plastic shaft having a plurality of individual cams formed integrally thereon.
Claim 10
Dependent Claim 26 words
Magnetic transducer positioning apparatus as defined in claim 8 wherein said means for moving said driving members further includes a stepper motor for rotating said shaft.
Claim 11
Dependent Claim 19 words
Magnetic transducer positioning apparatus as defined in claim 9 wherein said shaft is the shaft of said stepper motor.
Claim 12
Dependent Claim 34 words
Magnetic transducer positioning apparatus as defined in claim 10 wherein said shaft is positioned for rotation on a single ball disposed at each end thereof and received within a socket formed in said shaft.
Claim 13
Dependent Claim 25 words
Magnetic transducer positioning apparatus as defined in claim 11 wherein said stepper motor further includes a pair of permanent magnets securely affixed to said shaft.
Claim 14
Dependent Claim 23 words
Magnetic transducer positioning apparatus as defined in claim 11 which further includes a spring loaded arm for receiving one end of said shaft.
Claim 15
Dependent Claim 46 words
Magnetic transducer positioning apparatus as defined in claim 13 wherein said arm receives said shaft at one end thereof is supported upon a pivot point intermediate the ends thereof and receives a spring means at the other end thereof biasing said one end toward said shaft.
Claim 16
Dependent Claim 51 words
Magnetic transducer positioning apparatus as defined in claim 14 which further includes a plurality of balls contacting each of said first and second surfaces of said carriage and which further includes continuous track defining means restraining said balls for movement along predetermined paths to effectively float said carriage between said balls.
Claim 17
Dependent Claim 47 words
Magnetic transducer positioning apparatus as defined in claim 11 which further includes stop means for limiting the travel of said carriage beyond first and second limit positions, said spring loaded arm absorbing displacement of said shaft as said shaft urges said ball against said force receiving surfaces.
Claim 18
Dependent Claim 29 words
Magnetic transducer positioning apparatus as defined in claim 7 wherein said cam means has at least a single lobe for actuating one of said driving members at a time.
Claim 19
Dependent Claim 50 words
Magnetic transducer positioning apparatus as defined in claim 7 wherein said cam means has a plurality of cam surfaces only one of which at any one time actuates a driving member to align one of said surfaces on said first member with one of said surfaces on said second member.
Claim 20
Dependent Claim 19 words
Magnetic transducer positioning apparatus as defined in claim 18 wherein said cam surfaces are carried by an elongated shaft.
Claim 21
Dependent Claim 23 words
Magnetic transducer positioning apparatus as defined in claim 19 wherein said cam surfaces are formed as an integral part of said elongated shaft.
Claim 22
Dependent Claim 26 words
Magnetic transducer positioning apparatus as defined in claim 2 which further includes means for retaining said driving members aligned with said surface on said first member.
Claim 23
Dependent Claim 44 words
Magnetic transducer positioning apparatus as defined in claim 21 wherein said driving members are balls and said surfaces are recesses and said retaining means is a plate defining openings therein receiving said balls, said openings being aligned with the recesses in said first member.
Claim 24
Dependent Claim 21 words
Magnetic transducer positioning apparatus as defined in claim 1 wherein said second predetermined spacing is greater than said first predetermined spacing.
Claim 25
Dependent Claim 21 words
Magnetic transducer positioning apparatus as defined in claim 1 wherein said second predetermined spacing is less than said first predetermined spacing.

References Cited (Backward Citations)

US3818500A Cited
US3859662A Cited
US4261222A Cited
US4131923A Cited
US4270155A Cited
US4428012A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-06-17 1988-12-17 1989-06-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-06-17 1992-12-17 1993-06-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-06-17 1996-12-17 1997-06-18 $7700.00 Window Closed / Lapsed

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