US3906326A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fine and coarse track positioning system for a transducer in a magnetic recording system
Assignee: Caelus Memories Inc
•
Filing: 1970-06-03
•
Granted: 1975-09-16
•
Expires: 1990-06-03
Abstract
Abstract A linear positioning system is disclosed for precisely aligning magnetic transducer heads with a record medium as commanded by an address. Digital address signals are converted to an analog form to drive a linear motor which moves a transducer head to an approximation of the desired position. A servo loop incorporating a differentiator operates to stabilize the motor. Digital signals that are indicative of the final position are applied to an optical detent system to finally position the transducer heads and hold them in such position during a transducing interval.
Inventors
- 👤 Sung Pal Chur
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:29
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/39; G11; G11B; G11B5/00; G11B5/48; G11B5/58; G11B5/596; G11B5/59677
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
263 words
A positioning system for placing a magnetic transducer means in a predetermined positional relationship with a magnetic record member in accordance with a numerical value comprising: motor means for motivating said transducer means relative to a record member; coarse positioning means including means for providing a first analog signal related to a significant portion of said numerical value, to actuate said motor means so as to place said transducer means near said desired positional relationship; and position control means responsive to a selected least significant portion of said numerical value for sensing the position of said transducer means to provide a second analog signal after said element means has been positioned near said desired positional relationship to finally actuate said motor means to place said transducer at said predetermined positional relationship with said magnetic record member in accordance with said numerical value, wherein said means for providing a first analog signal includes input means for receiving said numerical value as a binary code of n bits, and wherein said coarse positioning means is responsive to (n-y) of the most significant of said n bits to provide said first analog signal, said coarse positioning means includes means for sensing the instant positional relationship of said transducer means with reference to said record member to provide a position signal; means for comparing said first analog signal with said position signal to provide a difference signal; and means for providing said difference signal to said motor means to place said transducer means near said desired positional relationship, n being greater than y and both being integers.
Claim 2
Dependent Claim
263 words
A positioning system for placing a magnetic transducer means in a predetermined positional relationship with a magnetic record member in accordance with a numerical value comprising: motor means for motivating said transducer means relative to a record member; coarse positioning means including means for providing a first analog signal related to a significant portion of said numerical value, to actuate said motor means so as to place said transducer means near said desired positional relationship; and position control means responsive to a selected least significant portion of said numerical value for sensing the position of said transducer means to provide a second analog signal after said element means has been positioned near said desired positional relationship to finally actuate said motor means to place said transducer at said predetermined positional relationship with said magnetic record member in accordance with said numerical value, wherein said means for providing a first analog signal includes input means for receiving said numerical value as a binary code of n bits, and wherein said coarse positioning means is responsive to (n-y) of the most significant of said n bits to provide said first analog signal, said coarse positioning means includes means for sensing the instant positional relationship of said transducer means with reference to said record member to provide a position signal; means for comparing said first analog signal with said position signal to provide a difference signal; and means for providing said difference signal to said motor means to place said transducer means near said desired positional relationship, n being greater than y and both being integers.
Claim 3
Dependent Claim
59 words
A system according to claim 1 further including differentiating means coupled to receive said position signal to provide a velocity signal; and means for reducing said difference signal in accordance with said velocity signal, said position control means including means responsive to the y least significant of said n bits, and optics means for providing said second analog signal.
Claim 4
Dependent Claim
52 words
A system according to claim 1 wherein said position control means include optical detent means for positioning said transducer means in an indexed position with reference to said record member under control of index signals provided as a function of the y least significant of the n bits in said numerical value.
Claim 5
Dependent Claim
100 words
A system according to claim 3 wherein said optical detent means comprises: a uniformly segmented light member; a phase segmented light member affixed for relative motion to said uniformly segmented light member with positional changes of said transducer means with reference to said record member; means for selectively energizing at least one phase of said phase segmented member under control of said index signals; and means for sensing a null position relationship between said selected phase of said phase segmented member and said uniformly segmented member to establish a final positional relationship between said transducer means and said record member.
Claim 6
Dependent Claim
160 words
An element positioning system comprising: input register means for receiving a numerical value in the form of a binary code of n bits, n being an integer, indicative of a desired element position; linear motor means for moving said element to a position defined by the numerical value in said input means; coarse position control means responsive to a significant portion of the numerical value in said input means and a present element position for providing a first control signal to said motor means to move said element near the position defined by said numerical value; and final position control means, operative after said element has moved near the position defined by said numerical value, responsive to a selective last significant portion of said numerical value and to the position of said element relative to a fixed member for providing a second control signal to said motor means to move said element to the position defined by said numerical value.
Claim 7
Dependent Claim
160 words
An element positioning system comprising: input register means for receiving a numerical value in the form of a binary code of n bits, n being an integer, indicative of a desired element position; linear motor means for moving said element to a position defined by the numerical value in said input means; coarse position control means responsive to a significant portion of the numerical value in said input means and a present element position for providing a first control signal to said motor means to move said element near the position defined by said numerical value; and final position control means, operative after said element has moved near the position defined by said numerical value, responsive to a selective last significant portion of said numerical value and to the position of said element relative to a fixed member for providing a second control signal to said motor means to move said element to the position defined by said numerical value.
Claim 8
Dependent Claim
71 words
A system according to claim 5 wherein said coarse position control means comprises means responsive to n-y of the most significant of said n bits for providing a first signal, means for providing a second signal as a function of element position and means for providing said first control signal as a function of the difference between said first and second signals, n being greater than y, y being an integer.
Claim 9
Dependent Claim
39 words
A system according to claim 5 further including means for generating an element velocity signal and means for providing said first control signal as a function of the difference between said first and second signals and said velocity signal.
Claim 10
Dependent Claim
100 words
A system according to claim 5 wherein said final position control means include means for providing a third signal which is a function of the y least significant of said n bits, optic means including first and second optic masks, said first optic mask being movable with said element by said motor means and said second optic mask being fixed to said fixed member, means for providing outputs as a function of the relative positions of said first and second optic masks and means for providing said second control signal as a function of said outputs and said third signal.
Claim 11
Dependent Claim
71 words
A system according to claim 8 wherein said coarse position control means comprises means responsive to n-y of the most significant of said n bits for providing a first signal, means for providing a second signal as a function of element position and means for providing said first control signal as a function of the difference between said first and second signals, n being greater than y, y being an integer.
Claim 12
Dependent Claim
39 words
A system according to claim 9 further including means for generating an element velocity signal and means for providing said first control signal as a function of the difference between said first and second signals and said velocity signal.
References Cited (Backward Citations)
US2907937A
Cited
US3193744A
Cited
US3105963A
Cited
US3156906A
Cited
US3292168A
Cited
US3372321A
Cited
US3226617A
Cited
US3362021A
Cited
US3426337A
Cited
US3458785A
Cited
US3512060A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-15 | 1979-03-17 | 1979-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-15 | 1983-03-17 | 1983-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-15 | 1987-03-17 | 1987-09-16 | $7700.00 | Window Closed / Lapsed |