Patent US4643552A successfully refreshed from Google Patents.
US4643552A
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Film transport indicator for cameras
Assignee: Ricoh Co Ltd
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Filing: 1985-03-18
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Granted: 1987-02-17
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Expires: 2005-03-18
Abstract
Abstract A film transport indicator for a camera with a motor drive includes a film transport signal generator for generating a film transport signal in response to a film being wound by the motor drive, a quasi-signal generator for generating a signal analogous to the film transport signal, and a switching circuit for passing said film transport signal when it is generated by said film transport signal generator and for passing the signal from said quasi-signal generator for a prescribed period of time when said film transport signal is ceased. The feeding of the film is indicated on an indicator unit in response to the signals having passed through the switching circuit.
Inventors
- 👤 Akira Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:44
CPC Classifications
G; G03; G03B; G03B17/00; G03B17/42; G03B17/425; G03B17/18
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
116 words
A film transport indicator for a camera with a motor drive, comprising: (a) a film transport signal generator for generating a film transport signal in response to a film being wound by the motor drive; (b) a quasi-signal generator for generating a signal analogous to said film transport signal; (c) switching means for passing said film transport signal when it is generated by said film transport signal generator and for passing the signal from said quasi-signal generator for a prescribed period of time when said film transport signal is ceased; and (d) an indicator unit for indicating feeding of the film to a camera user in response to the signals having passed through said switching means.
Claim 2
Dependent Claim
116 words
A film transport indicator for a camera with a motor drive, comprising: (a) a film transport signal generator for generating a film transport signal in response to a film being wound by the motor drive; (b) a quasi-signal generator for generating a signal analogous to said film transport signal; (c) switching means for passing said film transport signal when it is generated by said film transport signal generator and for passing the signal from said quasi-signal generator for a prescribed period of time when said film transport signal is ceased; and (d) an indicator unit for indicating feeding of the film to a camera user in response to the signals having passed through said switching means.
Claim 3
Dependent Claim
72 words
A film transport indicator according to claim 1, wherein said switching means comprises a first AND gate for passing said film transport signal when it is generated by said film transport signal generator, a timer operable for a prescribed period of time from the time when said film transport signal has been ceased, and a second AND gate for passing the signal from said quasi-signal generator while said timer is in operation.
Claim 4
Dependent Claim
18 words
A film transport indicator according to claim 1, wherein said indicator unit comprises lamps energizable by said signals.
Claim 5
Dependent Claim
20 words
A film transport indicator according to claim 1, wherein said indicator unit comprises liquid-crystal display elements energizable by said signals.
Claim 6
Dependent Claim
123 words
A film transport indicator for a camera with a motor drive, comprising: (a) a film transport signal generator for generating a film transport signal in response to a film being wound by the motor drive; (b) a quasi-signal generator for generating a signal analogous to said film transport signal; (c) switching means for passing said film transport signal when it is generated by said film transport signal generator and for passing the signal from said quasi-signal generator for a prescribed period of time when said film transport signal is ceased; and (d) a shift register for shifting the signals having passed through said switching means; and (e) an indicator unit for giving successive indications in response to output signals from said shift register.
Claim 7
Dependent Claim
123 words
A film transport indicator for a camera with a motor drive, comprising: (a) a film transport signal generator for generating a film transport signal in response to a film being wound by the motor drive; (b) a quasi-signal generator for generating a signal analogous to said film transport signal; (c) switching means for passing said film transport signal when it is generated by said film transport signal generator and for passing the signal from said quasi-signal generator for a prescribed period of time when said film transport signal is ceased; and (d) a shift register for shifting the signals having passed through said switching means; and (e) an indicator unit for giving successive indications in response to output signals from said shift register.
Claim 8
Dependent Claim
21 words
A film transport indicator according to claim 5, wherein said indicator unit comprises liquid-crystal display elements energizable by said output signals.
Claim 9
Dependent Claim
29 words
A film transport indicator according to claim 5, wherein said quasi-signal generator comprises an oscillator with an oscillation frequency thereof variable dependent on a power supply voltage applied thereto.
Claim 10
Dependent Claim
63 words
A film transport indicator according to claim 5, wherein said quasi-signal generator comprises an up/down counter for measuring intervals of shifting operation of said shift register while said film is being wound by the motor drive, and a latch for storing said measured intervals, said counter producing a borrow signal as the signal from said quasi-signal generator at each of said stored intervals.
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) | 1990-02-16 | 1990-08-18 | 1991-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-16 | 1994-08-18 | 1995-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-16 | 1998-08-18 | 1999-02-17 | $7700.00 | Window Closed / Lapsed |