US4107698A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ink jet printer apparatus and method of operation
Assignee: International Business Machines Corp
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Filing: 1977-02-10
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Granted: 1978-08-15
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Expires: 1997-02-10
Abstract
Abstract In a magnetic ink jet printer a continuous stream of ferrofluid ink drops is projected toward a print medium. A magnetic selector located proximate the stream is operated in synchronism with the flight of the ink drops for deflecting individual unwanted ink drops into a drop catcher. Due to fringing effects produced by the selector when unwanted drops are selected, adjacent print drops are deflected a lesser amount from the initial stream trajectory. Print drops not affected by the fringe magnetic field produced to select unwanted drops are subjected to a compensation deflection depending on their position relative to the unwanted drops so that all print drops follow the same trajectory, after passing the magnetic selector in their travel through a vertical deflector and deposition onto the print medium.
Inventors
- 👤 Louis Valentine Galetto
- 👤 Donald Frederick Jensen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 03:23
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/07; B41J2/075; B41J2/10; B41J2/015; B41J2/02; B41J2/035
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
166 words
An ink jet printer apparatus comprising in combination, means for projecting a continuous stream of individual ink drops toward a print medium; means for selectively removing unwanted ink drops from said stream while allowing print drops to be deposited on said print medium including, drop collector means positioned to prevent unwanted drops from depositing on said print medium, selector means operable for deflecting ink drops of said stream for interruption by said drop collector; and control means for operating said selector means for applying a first selection force capable of deflecting unwanted ink drops of said stream into a trajectory leading to said drop collector, said control means including means for operating said selector means for applying to at least some of the print drops of said stream a second deflection force which compensates for fringe deflection forces produced by said first selection force on said print drops whereby said print drops are caused to move in a common trajectory which avoids said drop collector means.
Claim 2
Dependent Claim
166 words
An ink jet printer apparatus comprising in combination, means for projecting a continuous stream of individual ink drops toward a print medium; means for selectively removing unwanted ink drops from said stream while allowing print drops to be deposited on said print medium including, drop collector means positioned to prevent unwanted drops from depositing on said print medium, selector means operable for deflecting ink drops of said stream for interruption by said drop collector; and control means for operating said selector means for applying a first selection force capable of deflecting unwanted ink drops of said stream into a trajectory leading to said drop collector, said control means including means for operating said selector means for applying to at least some of the print drops of said stream a second deflection force which compensates for fringe deflection forces produced by said first selection force on said print drops whereby said print drops are caused to move in a common trajectory which avoids said drop collector means.
Claim 3
Dependent Claim
41 words
An ink jet printer apparatus in accordance with claim 1 in which said second deflection force is selectively applied to individual print drops by said control means dependent on their proximity to unwanted ink drops subjected to said first deflection force.
Claim 4
Dependent Claim
61 words
An ink jet printer apparatus in accordance with claim 2 in which said second deflection force is applied by said control means to print drops unaffected by fringe deflection forces associated with said first deflection force whereby print drops unaffected by fringe deflection forces are caused to move in a common trajectory with print drops deflected by said fringe deflection forces.
Claim 5
Dependent Claim
55 words
An ink jet printer apparatus in accordance with claim 1 in which said ink drops are field controllable ink drops, and said selector means comprises transducer means operable by said control means for generating a force field proximate said stream for applying said first and second deflection forces to said unwanted and said print drops.
Claim 6
Dependent Claim
42 words
An ink jet printer apparatus in accordance with claim 4 in which said first controllable ink drops are magnetic ink drops, and said transducer means comprises a magnetic selector operable for generating a magnetic force field in the vicinity of said stream.
Claim 7
Dependent Claim
128 words
An ink jet printer apparatus in accordance with claim 5 in which said magnetic selector comprises a magnetic core element located in the vicinity of said stream for generating a gradient magnetic field proximate said stream, said gradient magnetic field operating to apply a deflection force to individual magnetic ink drops in said stream, an energizing winding on said magnetic core for producing flux in said core for the generation of said gradient magnetic field, and said control means comprises circuit means selectively operable for applying first and second levels of current to said energizing winding for producing said first and second deflection forces on said magnetic ink drops in synchronism with the alignment of said unwanted and said print magnetic ink drops with said magnetic core element.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-08-14 | 1982-02-13 | 1982-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-08-14 | 1986-02-13 | 1986-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-08-14 | 1990-02-13 | 1990-08-15 | $7700.00 | Window Closed / Lapsed |