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US3947851A Expired / Lapsed US ⏱️ 0.0 years remaining

Drop charging method for liquid drop recording

Assignee: International Business Machines Corp
•
Filing: 1974-06-27
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Granted: 1976-03-30
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Expires: 1994-06-27
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Abstract

Abstract Method of recording with a stream of marking fluid drops in which a predetermined plurality of successively formed drops in a stream each have the same electrical charge induced therein so that, when subsequently subjected to an electrostatic field, all drops of one commonly charged plurality will impact a record member at approximately the same spot. Drop charges are induced therein by asynchronously applied charging signal levels, each having a duration which is a function of the drop formation frequency and equal to at least two drop periods.

Inventors

  • 👤 Winston H. Chen
  • 👤 Ho C. Lee

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 02:36
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/21; B41J2/2121; B41J2/2128; B41J2/17; B41J2/18; B41J2/185

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 142 words
A method of recording with a jet of marking fluid on a recording surface comprising the steps of: generating a stream of drops of marking fluid of substantially uniform size and spacing directed toward a nonrecording location; inducing electrical charges in selected pluralities of successive drops for deposit on said recording surface with each drop in a selected plurality having the same charge as each other drop in said plurality and successive selected pluralities having different induced charge values thereon; and subjecting all said drops to an electrostatic field to deflect said drops in each selected plurality along substantially the same trajectory toward said surface according to the said induced charge thereon whereby the range of density of marking fluid on said recording surface is attained by varying the number of said successively and similarly charged drops impacting each predetermined recording area.
Claim 2
Independent Claim 142 words
A method of recording with a jet of marking fluid on a recording surface comprising the steps of: generating a stream of drops of marking fluid of substantially uniform size and spacing directed toward a nonrecording location; inducing electrical charges in selected pluralities of successive drops for deposit on said recording surface with each drop in a selected plurality having the same charge as each other drop in said plurality and successive selected pluralities having different induced charge values thereon; and subjecting all said drops to an electrostatic field to deflect said drops in each selected plurality along substantially the same trajectory toward said surface according to the said induced charge thereon whereby the range of density of marking fluid on said recording surface is attained by varying the number of said successively and similarly charged drops impacting each predetermined recording area.
Claim 3
Dependent Claim 29 words
A method according to claim 1 including the further step of producing relative movement between said record member and the drop generating source during the generation of said drops.
Claim 4
Dependent Claim 18 words
A method according to claim 1 wherein said charging signals are equal to at least three drop periods.
Claim 5
Dependent Claim 18 words
A method according to claim 1 wherein said charging signals have variable durations greater than two drop periods.

References Cited (Backward Citations)

US3373437A Cited
US3596275A Cited
GB1123188A Cited
US3787881A Cited
US3846800A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-03-30 1979-09-29 1980-03-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-03-30 1983-09-29 1984-03-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-03-30 1987-09-29 1988-03-30 $7700.00 Window Closed / Lapsed

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