US3898671A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ink jet recording
Assignee: AT&T Teletype Corp
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Filing: 1973-12-12
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Granted: 1975-08-05
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Expires: 1993-12-12
Abstract
Abstract An ink jet printing device wherein conductive ink, under pressure is emitted from a nozzle and breaks into droplets in the vicinity of a charging electrode such that the charge on each droplet is determined by the voltage on the charging electrode at the instant that the droplet separates from the solid stream of ink issuing from the nozzle. A mask or drain catcher is provided for blocking and catching uncharged droplets of ink, and an electrostatic field is provided for deflecting charged droplets out of a path impinging on the drain catcher and into a path impinging on a record medium for printing thereon. A vibratory transducer is connected to the nozzle structure and imparts undulations at a fixed, droplet-forming frequency to the ink issuing from the nozzle so as to induce the stream of ink to break into droplets of uniform size and spacing, at the applied droplet-forming frequency. A data signal source is connected to the charging electrode, and the phasing between the data signal and the droplet-forming signal is randomly varied to obviate distortions due to frequent, regular, or periodic formation or separation of droplets during transitions of the voltage of the charging signals.
Inventors
- 👤 James M Berry
- 👤 Anthony J Hauser
- 👤 Gary B Ollendick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 01:16
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/07; B41J2/115
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
171 words
An improved ink jet printing system of the type wherein ink is delivered to a nozzle, a transducer vibrates the delivered ink in response to drive signals applied thereto, the ink breaks into droplets after issuing from the nozzle, a charging electrode is positioned in the region in which the ink jet breaks into droplets, the charging electrode is adapted to respond to data signals selectively to charge the droplets as they are formed, the improvement comprising: data signal source means for applying data signals to the charging electrode at a first predetermined frequency; vibratory drive means for applying drive signals to the transDucer at a predetermined frequency which may differ from the first predetermined frequency, whereby a phase relationship exists between the formation of droplets and transitions in the data signals; and means for randomly varying the phasing relationship between the data signals and the drive signals from data signal to data signal, thereby reducing the statistical likelihood that droplets will be formed on successive transitions in the data signals.
Claim 2
Dependent Claim
171 words
An improved ink jet printing system of the type wherein ink is delivered to a nozzle, a transducer vibrates the delivered ink in response to drive signals applied thereto, the ink breaks into droplets after issuing from the nozzle, a charging electrode is positioned in the region in which the ink jet breaks into droplets, the charging electrode is adapted to respond to data signals selectively to charge the droplets as they are formed, the improvement comprising: data signal source means for applying data signals to the charging electrode at a first predetermined frequency; vibratory drive means for applying drive signals to the transDucer at a predetermined frequency which may differ from the first predetermined frequency, whereby a phase relationship exists between the formation of droplets and transitions in the data signals; and means for randomly varying the phasing relationship between the data signals and the drive signals from data signal to data signal, thereby reducing the statistical likelihood that droplets will be formed on successive transitions in the data signals.
Claim 3
Dependent Claim
26 words
A system according to claim 1 wherein the predetermined frequency of the drive signals is the same as the first predetermined frequency of the data signals.
Claim 4
Dependent Claim
26 words
A system according to claim 1 wherein the predetermined frequency of the drive signals is a function of the first predetermined frequency of the data signals.
Claim 5
Dependent Claim
30 words
A signal according to claim 1 wherein the predetermined frequency of the drive signals is a function of the first predetermined frequency and the rise time of the data signals.
Claim 6
Dependent Claim
78 words
A system according to claim 1 wherein the randomly varying means comprises a means for delaying by a random duration the application of data signals to the charging electrode. 6. A system according to claim 5 having a timing pulse generator means with an output for initiating application of the data signals to the charging electrode and wherein the random delaying means comprises means for imparting a random delay to the output of the timing pulse generator means.
Claim 7
Dependent Claim
53 words
A system according to claim 6 further comprising a random pulse generator having an output and wherein the means for imparting a random delay to the output of the timing pulse generator means comprises means for gating the output of the timing pulse generator means with the output of the random pulse generator.
Claim 8
Dependent Claim
29 words
A system according to claim 7 comprising means for storing the output of the timing pulse generator means for later gating with subsequent output of the random pulse generator.
Claim 9
Dependent Claim
29 words
A system according to claim 1 wherein the first predetermined frequency of the data signals is a function of the frequency of the drive signals applied to the transducer.
Claim 10
Dependent Claim
33 words
A system according to claim 1 wherein the predetermined frequency of the data signals is a function of the predetermined frequency of the drive signals and the rise time of the data signals.
References Cited (Backward Citations)
US3298030A
Cited
US3588906A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-04 | 1979-02-03 | 1979-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-04 | 1983-02-03 | 1983-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-04 | 1987-02-03 | 1987-08-05 | $7700.00 | Window Closed / Lapsed |