US3733612A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signature reproduction
Assignee: SIGNA SIGNER Inc
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Filing: 1971-03-30
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Granted: 1973-05-15
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Expires: 1991-03-30
Abstract
Abstract The position of a pen or stylus with respect to a piece of paper is converted into two DC signals in a pair of potentiometers which are mechanically linked to the pen support mechanism. The DC signals are then converted into AC signals which are recorded on magnetic tape. When the tape is played back, the AC signals are reconverted into DC voltages which drive a negative feedback servomechanism system and thereby reproduce a signature previously recorded on the magnetic tape.
Inventors
- 👤 H Huston
- 👤 D Belcher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:48
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/485; B41J2/49
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
206 words
A handwriting reproducing machine comprising a writing element; a writing surface; support means for holding said element and for mechanically indicating the position of said element, said indication being in the form of first and second coordinates; first and second conversion means for converting said first and second coordinates into first and second DC voltages, respectively; first and second voltage-to-frequency converters for converting said first and second DC voltages into first and second AC signals, respectively, the frequency of said first and second AC signals being related to the magnitude of said first and second DC voltages, respectively recording means having first and second channels for recording and reproducing said first and second AC signals; first and second demodulation means associated with said first and second channels for converting said first and second AC signals into first and second reproduce DC voltages, respectively; first comparison means associated with said first conversion means for comparing said first DC voltage with said first reproduce DC voltage; second comparison means associated with said second conversion means for comparing said second DC voltage with said second reproduce DC voltage; first and second motive means connected to said first and second comparison means and mechanically linked to drive said support means.
Claim 2
Dependent Claim
206 words
A handwriting reproducing machine comprising a writing element; a writing surface; support means for holding said element and for mechanically indicating the position of said element, said indication being in the form of first and second coordinates; first and second conversion means for converting said first and second coordinates into first and second DC voltages, respectively; first and second voltage-to-frequency converters for converting said first and second DC voltages into first and second AC signals, respectively, the frequency of said first and second AC signals being related to the magnitude of said first and second DC voltages, respectively recording means having first and second channels for recording and reproducing said first and second AC signals; first and second demodulation means associated with said first and second channels for converting said first and second AC signals into first and second reproduce DC voltages, respectively; first comparison means associated with said first conversion means for comparing said first DC voltage with said first reproduce DC voltage; second comparison means associated with said second conversion means for comparing said second DC voltage with said second reproduce DC voltage; first and second motive means connected to said first and second comparison means and mechanically linked to drive said support means.
Claim 3
Dependent Claim
31 words
A machine as in claim 1 wherein said support means comprises first and second shafts, the angular orientation of said first and second shafts indicating said first and second coordinates, respectively.
Claim 4
Dependent Claim
48 words
A machine as in claim 2 wherein said first and second conversion means comprise first and second potentiometers mounted on said first and second shafts, respectively, and wherein said first and second motive means comprise first and second servo motors mounted on said first and second shafts, respectively.
Claim 5
Dependent Claim
67 words
A machine as in claim 3 wherein said first and second comparison means comprise first and second differential amplifiers, respectively, said first differential amplifier having a first input connected to said first potentiometer and a second input connected to said first demodulation means and said second differential amplifier having a first input connected to said second potentiometer and a second input connected to said second demodulation means.
Claim 6
Dependent Claim
26 words
A machine as in claim 4 wherein the outputs of said first and second differential amplifiers are connected to said first and second servo motors, respectively.
Claim 7
Dependent Claim
41 words
A machine as in claim 5 wherein said recording means comprises a magnetic tape recorder having a first record and a first reproduce terminal in said first channel and a second record and a second reproduce terminal in said second channel.
Claim 8
Dependent Claim
75 words
A machine as in claim 6 wherein said first demodulation unit comprises a first buffer amplifier, a first Schmitt trigger, a first one shot multivibrator, and a first integrator, connected in series; and wherein said second demodulation unit comprisEs a second buffer amplifier, a second Schmitt trigger, a second one shot multivibrator, and a second integrator, connected in series, said first and second buffer amplifiers being connected to said first and second reproduce terminals, respectively.
Claim 9
Dependent Claim
50 words
A machine as in claim 7 wherein said support means comprises means for lifting said writing element from said writing surface, and additionally comprising lift sensing means for sensing whether said writing element is in contact with said surface, said lift sensing means being connected to said second record channel.
Claim 10
Dependent Claim
57 words
A machine as in claim 8 comprising activation means for lifting and lowering said writing element with respect to said writing surface and first and second filters, said first filter being connected between said second reproduce terminal and said activation means and said second filter being connected between said second reproduce terminal and said second demodulation means.
References Cited (Backward Citations)
US3425140A
Cited
US3582956A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-14 | 1976-11-13 | 1977-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-14 | 1980-11-13 | 1981-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-14 | 1984-11-13 | 1985-05-15 | $7700.00 | Window Closed / Lapsed |