US4814796A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct electrostatic printing apparatus and toner/developer delivery system therefor
Assignee: Xerox Corp
•
Filing: 1986-11-03
•
Granted: 1989-03-21
•
Expires: 2006-11-03
Abstract
Abstract Direct electrostatic printing apparatus including structure for delivering developer or toner particles to a printhead forming an integral part of the printing device. The printing device includes, in addition to the printhead, a conductive shoe which is suitably biased during a printing cycle to assist in the electrostatic attraction of developer through apertures in the printhead onto the copying medium disposed intermediate the printhead and the conductive shoe. The structure for delivering developer or toner is adapted to deliver toner containing a minimum quantity of wrong sign and size toner. To this end, the developer delivery system includes a conventional magnetic brush which delivers toner to a donor roll structure which, in turn, delivers toner to the vicinity of apertures in the printhead structure.
Inventors
- 👤 Fred W. Schmidlin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:50
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/22; G03G15/34; G03G15/344; G03G15/346; G03G15/06; G03G15/08; G03G15/0822; G03G15/0887; G03G15/0891; G03G2217/00; G03G2217/0008; G03G2217/0025
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
119 words
Printing apparatus including a toner delivery system, a printhead structure containing a plurality of apertures adapted to transport toner therethrough which toner is supplied by said delivery system to the vicinity of said apertures and means for supporting copy substrates for movement past said printhead, said supporting means being adapted to attract toner transported from said delivery system through said printhead whereby said toner is deposited in image configuration on said copy substrate, the improvement comprising: a toner deliver system including means for conditioning said toner for minimizing clogged of said apertures in said printhead and donor structure for conveying said conditioned toner from said conditioning means to areas adjacent said apertures said conditioning means including a movable member.
Claim 2
Dependent Claim
119 words
Printing apparatus including a toner delivery system, a printhead structure containing a plurality of apertures adapted to transport toner therethrough which toner is supplied by said delivery system to the vicinity of said apertures and means for supporting copy substrates for movement past said printhead, said supporting means being adapted to attract toner transported from said delivery system through said printhead whereby said toner is deposited in image configuration on said copy substrate, the improvement comprising: a toner deliver system including means for conditioning said toner for minimizing clogged of said apertures in said printhead and donor structure for conveying said conditioned toner from said conditioning means to areas adjacent said apertures said conditioning means including a movable member.
Claim 3
Dependent Claim
23 words
Printing apparatus according to claim 1 wherein said donor structure is adapted to gently convey said toner to said areas adjacent said apertures.
Claim 4
Dependent Claim
20 words
Printing apparatus according to claim 1 wherein said conditioning means comprises means for optimizing the charge distribution of said toner.
Claim 5
Dependent Claim
14 words
Printing apparatus according to claim 3 wherein said conditioning means comprises a magnetic brush.
Claim 6
Dependent Claim
34 words
Printing apparatus according to claim 4 including means for electrically biasing said magnetic brush to thereby create an electrostatic field for effecting movement of said toner from said magnetic brush to said donor structure.
Claim 7
Dependent Claim
38 words
Apparatus according to claim 5 including means for electrically biasing said donor structure to thereby produce a weak oscillating energy field for effecting gentle movement of said toner from said donor structure to said areas adjacent said apertures.
Claim 8
Dependent Claim
24 words
Apparatus according to claim 6 wherein said donor structure comprises a roll member supported for rotation intermediate said magnetic brush and said printhead structure.
Claim 9
Dependent Claim
25 words
Apparatus according to claim 7 including means for electrically biasing said supporting means to thereby create an electronic field for attracting toner to said substrate.
Claim 10
Dependent Claim
27 words
Apparatus according to claim 8 wherein said printhead sturcture comprises a plurality of control electrodes and a continuous shield electrode on opposite sides of the printhead structure.
Claim 11
Dependent Claim
18 words
Apparatus according to claim 9 wherein said donor structure is spaced approximately 0.006 inch from said printhead structure.
Claim 12
Dependent Claim
18 words
Apparatus according to claim 10 wherein said supporting means positions said substrate approximately 0.005 inch from said printhead.
Claim 13
Dependent Claim
15 words
Apparatus according to claim 11 including means for periodically removing toner adhered to said printhead.
Claim 14
Dependent Claim
53 words
Toner delivery apparatus for presenting toner to a printhead structure, said toner delivery system comprising: means for conditioning said toner for minimizing clogging of said apertures in said printhead and donor structure for conveying said conditioned toner from said conditioning means to areas adjacent said apertures said conditioning means including a movable member.
Claim 15
Dependent Claim
53 words
Toner delivery apparatus for presenting toner to a printhead structure, said toner delivery system comprising: means for conditioning said toner for minimizing clogging of said apertures in said printhead and donor structure for conveying said conditioned toner from said conditioning means to areas adjacent said apertures said conditioning means including a movable member.
Claim 16
Dependent Claim
22 words
Apparatus according to claim 13 wherein said donor structure is adapted to gently convey toner to areas adjacent apertures in said printhead.
Claim 17
Dependent Claim
19 words
Apparatus according to claim 14 wherein said conditioning means comprises means for optimizing the charge distribution of said toner.
Claim 18
Dependent Claim
13 words
Apparatus according to claim 15 wherein said conditioning means comprises a magnetic brush.
Claim 19
Dependent Claim
33 words
Apparatus according to claim 16 including means for electrically biasing said magnetic brush to thereby create an electrostatic field for effecting movement of said toner from said magnetic brush to said donor structure.
Claim 20
Dependent Claim
38 words
Apparatus according to claim 17 including means for electrically biasing said donor structure to thereby produce a weak oscillating energy field for effecting gentle movement of said toner from said donor structure to said areas adjacent said apertures.
Claim 21
Dependent Claim
24 words
Apparatus according to claim 18 wherein said donor structure comprises a roll member supported for rotation intermediate said magnetic brush and said printhead structure.
Claim 22
Dependent Claim
18 words
Apparatus according to claim 19 wherein said donor structure is spaced approximately 0.006 inch from said printhead structure.
Claim 23
Dependent Claim
15 words
Apparatus according to claim 20 including means for periodically removing toner adhered to said printhead.
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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) | 1992-03-20 | 1992-09-19 | 1993-03-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-20 | 1996-09-19 | 1997-03-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-20 | 2000-09-19 | 2001-03-21 | $7700.00 | Window Closed / Lapsed |