EP0266960A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Direct electrostatic printing apparatus and printhead cleaning structure therefor
Assignee: Xerox Corp
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Filing: 1987-10-29
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Granted: —
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Expires: 2007-10-29
Abstract
Abstract Direct Electrostatic Printing apparatus including structure (40, 43) for removing wrong sign developer particles from a printhead (14) forming an integral part of the printing device. The printing device includes, in addition to the printhead, a conductive shoe (16) which is suitably biased (38) during a printing cycle to assist in the electrostatic attraction of developer passing through apertures (36) in the printhead onto the copying medium (30) disposed intermediate the printhead and the conductive shoe. During a cleaning cycle, the printing bias (38) is removed from the shoe and an electrical bias (43) suitable for creating an oscillating electrostatic field which effects removal of toner from the printhead is applied (40) to the shoe.
Inventors
- 👤 Fred William Schmidlin
- 👤 John David Sotack
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 16:17
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/385; B41J2/41; B41J2/415; B41J2/4155; G; G03; G03G; G03G15/00; G03G15/22; G03G15/34; G03G15/344; G03G15/346; G03G2217/00; G03G2217/0008; G03G2217/0025
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
45 words
Apparatus for removing toner from a printhead (14) having a plurality of apertures (36) used in a printing system, characterised: means (34, 16, 43) for creating an electrostatic field in the vicinity of said apertures capable of effecting removal of toner particles from said printhead.
Claim 2
Dependent Claim
45 words
Apparatus for removing toner from a printhead (14) having a plurality of apertures (36) used in a printing system, characterised: means (34, 16, 43) for creating an electrostatic field in the vicinity of said apertures capable of effecting removal of toner particles from said printhead.
Claim 3
Dependent Claim
13 words
Apparatus according to claim 1 wherein said electrostatic field comprises an oscillating field.
Claim 4
Dependent Claim
36 words
Apparatus according to claim 2 wherein said means for creating an electrostatic field comprises electrical bias means (43) adapted for periodically applying an AC.voltage to supporting means (16) which positions copy substrates (30) adjacent said printhead.
Claim 5
Dependent Claim
93 words
Printing apparatus including a toner delivery system (12), a printhead structure (14) containing a plurality of apertures (36) adapted to transport toner therethrough which toner is supplied by said delivery system to the vicinity of said apertures, and means (16) for supporting copy substrates (30) for movement past said printhead, said supporting means (16) 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, and a toner removal apparatus according to any one of claims 1 to 3.
Claim 6
Dependent Claim
45 words
Apparatus according to claim 4 wherein the toner delivery system includes means (18) for conditioning said toner for minimizing clogging of said apertures in said printhead, and a donor structure (24) for conveying said conditioned toner from said conditioning means to areas adjacent said apertures.
Claim 7
Dependent Claim
15 words
Printing apparatus according to claim 5 wherein said conditioning means (18) comprises a magnetic brush.
Claim 8
Dependent Claim
35 words
Printing apparatus according to claim 6 including means (26) 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 9
Dependent Claim
40 words
Apparatus according to claim 7 including means (28, 29) 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 10
Dependent Claim
25 words
Apparatus according to claim 8 wherein said donor structure (24) comprises a roll member supported for rotation intermediate said magnetic brush and said printhead structure.
Claim 11
Dependent Claim
26 words
Apparatus according to claim 9 including means (38) for electrically biasing said supporting means to thereby create an electrostatic field for attracting toner to said substrate.
References Cited (Backward Citations)
No citation records indexed.
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