US4625221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for ejecting droplets of ink
Assignee: Fujitsu Ltd
•
Filing: 1985-04-05
•
Granted: 1986-11-25
•
Expires: 2005-04-05
Abstract
Abstract An apparatus for ejecting droplets of ink including: a passage for ink; an orifice disposed at one end of the passage; a pressure-applying device for applying a pressure wave to the ink within the passage; and a signal-supplying device for supplying an actuating signal to the pressure-applying device. The frequency of the signal is such that the displacement of the ink surface at the orifice due to the pressure wave is maximized.
Inventors
- 👤 Tsuneo Mizuno
- 👤 Noboru Takada
- 👤 Michio Shimura
- 👤 Tohru Satoh
- 👤 Tadashi Matsuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:04
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/015; B41J2/04; B41J2/045; B41J2/04501; B41J2/04541; B41J2/04581
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
211 words
An apparatus for ejecting droplets of ink, comprising: a passage for the ink; an orifice disposed at one end of said passage; pressure-applying means, communicating with the ink in said passage, for applying a pressure wave to the ink within said passage, comprising a piezoelectric crystal chip; and signal-supplying means, operatively connected to said piezoelectric crystal chip, for supplying an actuating pulse signal to said piezoelectric crystal chip, said actuating pulse signal rising gradually and falling sharply and having a frequency which maximizes the displacement due to said pressure wave of the ink surface at said orifice, said signal-supplying means including-- power source means for supplying power; a first transistor having an emitter operatively connected to ground and a collector operatively connected to said power source means; a second transistor having a collector operatively connected to said power source means, a base operatively connected to the collector of said first transistor and an emitter; a first diode operatively connected to the emitter of said second transistor; a first resistance operatively connected to said first diode and said piezoelectric crystal chip; a second diode operatively connected to said first resistance and said piezoelectric crystal chip; and a second resistance operatively connected to said second diode and the base of said second transistor.
Claim 2
Independent Claim
211 words
An apparatus for ejecting droplets of ink, comprising: a passage for the ink; an orifice disposed at one end of said passage; pressure-applying means, communicating with the ink in said passage, for applying a pressure wave to the ink within said passage, comprising a piezoelectric crystal chip; and signal-supplying means, operatively connected to said piezoelectric crystal chip, for supplying an actuating pulse signal to said piezoelectric crystal chip, said actuating pulse signal rising gradually and falling sharply and having a frequency which maximizes the displacement due to said pressure wave of the ink surface at said orifice, said signal-supplying means including-- power source means for supplying power; a first transistor having an emitter operatively connected to ground and a collector operatively connected to said power source means; a second transistor having a collector operatively connected to said power source means, a base operatively connected to the collector of said first transistor and an emitter; a first diode operatively connected to the emitter of said second transistor; a first resistance operatively connected to said first diode and said piezoelectric crystal chip; a second diode operatively connected to said first resistance and said piezoelectric crystal chip; and a second resistance operatively connected to said second diode and the base of said second transistor.
Claim 3
Dependent Claim
19 words
An apparatus for ejecting droplets of ink as set forth in claim 1, wherein said first resistance is variable.
References Cited (Backward Citations)
US2512743A
Cited
US3946398A
Cited
US3683396A
Cited
US3683212A
Cited
US4112433A
Cited
US4282535A
Cited
US4266232A
Cited
DE3026768A1
Cited
US4471363A
Cited
US4398204A
Cited
US4369455A
Cited
US4393384A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-24 | 1990-05-26 | 1990-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-24 | 1994-05-26 | 1994-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-24 | 1998-05-26 | 1998-11-25 | $7700.00 | Window Closed / Lapsed |