US4297692A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Segment failure detector for digital display
Assignee: Simmonds Precision Products Inc
•
Filing: 1980-04-08
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Granted: 1981-10-27
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Expires: 2000-04-08
Abstract
No abstract record available.
Inventors
- 👤 Lawrence C. Maier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:17
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/006; G06; G06F; G06F11/00; G06F11/07; G06F11/0703; G06F11/079; G09G3/04
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
149 words
A digital display device including: a power source connected to drive the digital display device; a plurality of character-forming display segments; a driver circuit connected to the plurality of display segments to selectively energize the plurality of display segments; a failure detection circuit connected to the plurality of display segments to detect the failure of any of the plurality display segments to energize; and to generate a blanking signal indicative of display segment failure; an override circuit to override the blanking signal; wherein the driver circuit is connected to the failure detection circuit to receive the blanking signal such that the driver circuit de-energizes the plurality of display segments on receipt of the blanking signal; and wherein the override circuit is connected to the driver circuit such that the timer circuit overrides the blanking signal to permit energizing of the plurality of non-failed display segments by the driver circuit.
Claim 2
Dependent Claim
149 words
A digital display device including: a power source connected to drive the digital display device; a plurality of character-forming display segments; a driver circuit connected to the plurality of display segments to selectively energize the plurality of display segments; a failure detection circuit connected to the plurality of display segments to detect the failure of any of the plurality display segments to energize; and to generate a blanking signal indicative of display segment failure; an override circuit to override the blanking signal; wherein the driver circuit is connected to the failure detection circuit to receive the blanking signal such that the driver circuit de-energizes the plurality of display segments on receipt of the blanking signal; and wherein the override circuit is connected to the driver circuit such that the timer circuit overrides the blanking signal to permit energizing of the plurality of non-failed display segments by the driver circuit.
Claim 3
Dependent Claim
29 words
A digital display device as defined in claim 1 where: the means to override the blanking signal includes a timing means to determine the duration of the blanking signal.
Claim 4
Dependent Claim
63 words
A digital display device as defined in claim 2 wherein: the failure detection circuit includes a comparator having an input connected to the plurality of display segments and further having an output connected to the driver circuit such that the comparator output has a first value representing the absence of a failed display segment and has a second value representing the blanking signal.
Claim 5
Dependent Claim
62 words
A digital display device as defined in claim 3 wherein: the driver circuit is connected to each of the plurality of display segments via a plurality of resistors; and further wherein the comparator is connected to each of the plurality of display segments via a plurality of diodes at a junction between the plurality of resistors and the plurality of display segments.
Claim 6
Dependent Claim
27 words
A digital display device as defined in claim 4 wherein: the comparator output is connected to the driver circuit via a flip-flop which stores the blanking signal.
Claim 7
Dependent Claim
17 words
A digital display device as defined in claim 5 wherein: the failure detector circuit is manually operated.
Claim 8
Dependent Claim
45 words
A digital display device as defined in claim 6 wherein: the override circuit to override the blanking signal includes a circuit means connected to the flip-flop such that the circuit means clears the blanking signal from the flip-flop upon operation of the failure detection circuit.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-10-26 | 1985-04-27 | 1985-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-26 | 1989-04-27 | 1989-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-26 | 1993-04-27 | 1993-10-27 | $7700.00 | Window Closed / Lapsed |