US5887221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signature sensing for optimum toner control with donor roll
Assignee: Xerox Corp
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Filing: 1997-10-20
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Granted: 1999-03-23
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Expires: 2017-10-20
Abstract
Abstract Reload characteristics of a development member such as a donor roll are monitored by using a machine exposure system (ROS or LED Bar) to generate a test image composed of a short (in the process direction) high density solid area patch followed by a long mid and lower density areas (solid or halftone), the later corresponding to Reload Defect (RD) exhibited by the development member. Typical dimensions of the test image would be a 15 mm square high density patch followed by a 200×15 mm mid and lower density regions. This test image voltage profile is placed in a skipped image frame inserted into a long job, or is effected during cycle-out/down following a shorter job run, and is scheduled at infrequent periodic intervals, for example, every 2000 prints. The resultant developed toner pattern on the photoreceptor is monitored, for example, with a reflectance or transmission density sensor such as the Toner Area Coverage (TAC) sensor used in the 4700™, 4850™, and 5775™ imaging products or an Extended Toner Area Coverage (ETAC) sensor. The toner dispense rate is adjusted to obtain a desired level of Reload Defect in the developed toner patter which corresponds to the optimum level of Toner Concentration in the development system.
Inventors
- 👤 Robert E. Grace
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 11:13
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0822; G03G15/0848; G03G15/0849; G03G15/0855; G03G15/50; G03G15/5033; G03G15/5041; G03G15/55; G03G15/553; G03G15/556; G03G2215/00; G03G2215/00025; G03G2215/00029; G03G2215/00033; G03G2215/00037; G03G2215/00042
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
189 words
Image creation apparatus, said apparatus comprising: a circulation change retentive surface; means for uniformly changing said charge retentive surface; exposure means for imagewise discharging said uniformly charged charge retentive surface for forming latent electrostatic images in the form of a test patch voltage profile on said charge retentive surface, said test patch voltage profile being formed in the direction of circulation of said charge retentive surface and comprising a short high density solid area followed by a longer mid and low density solid area; a non interactive development system for developing said test patch voltage representing development characteristics of said development system, a toner dispenser for replenishing toner in said development system; motor means for effecting operation of said toner dispenser; means for monitoring said developed test patch and generating an electrical output corresponding to a developed density; means for comparing said electrical output to a value stored in memory which corresponds to the speed of a toner dispenser motor; and means responsive to said means for comparing for adjusting the operation of said motor means when said output from said means for comparing differs form said stored value.
Claim 2
Dependent Claim
189 words
Image creation apparatus, said apparatus comprising: a circulation change retentive surface; means for uniformly changing said charge retentive surface; exposure means for imagewise discharging said uniformly charged charge retentive surface for forming latent electrostatic images in the form of a test patch voltage profile on said charge retentive surface, said test patch voltage profile being formed in the direction of circulation of said charge retentive surface and comprising a short high density solid area followed by a longer mid and low density solid area; a non interactive development system for developing said test patch voltage representing development characteristics of said development system, a toner dispenser for replenishing toner in said development system; motor means for effecting operation of said toner dispenser; means for monitoring said developed test patch and generating an electrical output corresponding to a developed density; means for comparing said electrical output to a value stored in memory which corresponds to the speed of a toner dispenser motor; and means responsive to said means for comparing for adjusting the operation of said motor means when said output from said means for comparing differs form said stored value.
Claim 3
Dependent Claim
32 words
Apparatus according to claim 1 wherein said voltage profile is about 15 mm square in the high density solid area and an of about 200×15 mm containing mid and lower density areas.
Claim 4
Dependent Claim
22 words
Apparatus according to claim 2 wherein said voltage profile is created periodically in a skipped image frame inserted into a long job.
Claim 5
Dependent Claim
16 words
Apparatus according to claim 1 wherein said means for comparing comprises a pattern recognition algorithm device.
Claim 6
Dependent Claim
182 words
Method of image creation apparatus, said method including the steps of: circulating a charge retentive surface; uniformly charging said charge retention surface; imagewise discharging said uniformly charged charge retentive surface for forming a latent electrostatic image in the form of a test patch voltage profile on said charge retentive surface, said test patch voltage profile being formed in the direction of circulation of said charge retentive surface and comprising a short high density solid area followed by a longer mid and low density solid area; using a non interactive development system, developing said test patch voltage profile for providing development characteristics of said development system, replenishing toner in said development system by a toner dispenser; effecting operation of said toner dispenser by a motor means; monitoring said developed test patch and generating an electrical output corresponding to developed density; comparing said electrical output to a value stored in memory which corresponds to the speed of said toner dispenser motor; and adjusting the operation of said motor means in response to said comparing step when said electrical output differs from said stored value.
Claim 7
Dependent Claim
182 words
Method of image creation apparatus, said method including the steps of: circulating a charge retentive surface; uniformly charging said charge retention surface; imagewise discharging said uniformly charged charge retentive surface for forming a latent electrostatic image in the form of a test patch voltage profile on said charge retentive surface, said test patch voltage profile being formed in the direction of circulation of said charge retentive surface and comprising a short high density solid area followed by a longer mid and low density solid area; using a non interactive development system, developing said test patch voltage profile for providing development characteristics of said development system, replenishing toner in said development system by a toner dispenser; effecting operation of said toner dispenser by a motor means; monitoring said developed test patch and generating an electrical output corresponding to developed density; comparing said electrical output to a value stored in memory which corresponds to the speed of said toner dispenser motor; and adjusting the operation of said motor means in response to said comparing step when said electrical output differs from said stored value.
Claim 8
Dependent Claim
33 words
The method according to claim 5 wherein said voltage profile is about 15 mm square in the high density solid area and an of about 200×15 mm containing mid and lower density areas.
Claim 9
Dependent Claim
23 words
The method according to claim 6 wherein said voltage profile is created periodically in a skipped image frame inserted into a long job.
Claim 10
Dependent Claim
17 words
The method according to claim 5 wherein said value stored in memory comprises a pattern recognition algorithm.
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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) | 2002-03-22 | 2002-09-21 | 2003-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-03-22 | 2006-09-21 | 2007-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-03-22 | 2010-09-21 | 2011-03-23 | $7700.00 | Window Closed / Lapsed |