Patent US4894805A successfully refreshed from Google Patents.
US4894805A
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Security printer/copier
Assignee: Eastman Kodak Co
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Filing: 1988-04-28
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Granted: 1990-01-16
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Expires: 2008-04-28
Abstract
Abstract A printer/copier which stores job image data in memory before reproduction has a "refresh period" after which data stored therein will degrade if the device is not refreshed. Upon completion of a "security" job, DRAM refresh and normal read or write operations are disabled for a time period sufficient to allow the data resident in the DRAM to degrade.
Inventors
- 👤 Russell L. Godshalk
- 👤 Gary W. Shope
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:40
CPC Classifications
G; G11; G11C; G11C7/00; G11C7/24; G06; G06F; G06F21/00; G06F21/70; G06F21/78; G06F21/79; G06F21/82; G06F21/84; G06F2221/00; G06F2221/21; G06F2221/2143
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
53 words
In a copier/printer having a memory for storing job image data, the memory being of the type requiring periodic refresh to prevent degradation of stored data; the improvement comprising security means for disabling memory refresh for a time period sufficient to allow the data to degrade sufficiently to be unrecoverable in recognizable form.
Claim 2
Dependent Claim
53 words
In a copier/printer having a memory for storing job image data, the memory being of the type requiring periodic refresh to prevent degradation of stored data; the improvement comprising security means for disabling memory refresh for a time period sufficient to allow the data to degrade sufficiently to be unrecoverable in recognizable form.
Claim 3
Dependent Claim
42 words
The improvement defined in claim 1 wherein: the memory is a dynamic random access memory refreshed by application of a Row-Access-Strobe clock signal; and said security means comprises means for inhibiting application of Row-Access-Strobe clock signals to the dynamic random access memory.
Claim 4
Dependent Claim
39 words
The improvement defined in claim 1 wherein: the memory is a dynamic random access memory refreshed by read and write operations; and said security means comprises means for disabling read and write operations to the dynamic random access memory.
Claim 5
Dependent Claim
15 words
The improvement defined in claim 1 further comprising means for selectively enabling said security means.
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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) | 1993-01-15 | 1993-07-17 | 1994-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-15 | 1997-07-17 | 1998-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-15 | 2001-07-17 | 2002-01-16 | $7700.00 | Window Closed / Lapsed |