US4301459A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ink ejection apparatus comprising entrained air removal means
Assignee: Ricoh Co Ltd
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Filing: 1979-10-29
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Granted: 1981-11-17
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Expires: 1999-10-29
Abstract
Abstract An air removal unit (36) is disposed in a conduit (35) leading from an ink reservoir (34) to an ink ejection head (37). The amount of entrained air in the ink in the head (37) is sensed, and a heater (39) connected to the removal unit (36) is energized to heat the ink and boost the air removal efficiency when the amount of entrained air is above a certain value. The air removal unit (36) includes a container (47) and partitions (51), (52) provided in the container (47) to define chambers. The ink flows upwardly and downwardly through the chambers and the entrained air rises into a collection chamber (54) from which it is vented to the atmosphere.
Inventors
- 👤 Takuro Isayama
- 👤 Hiromichi Komai
- 👤 Hiroshi Yamazaki
- 👤 Tsutomu Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:37
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/17; B41J2/19
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
90 words
An ink ejection apparatus including an ink reservoir, an ink ejection head and a conduit connecting the reservoir to the head, characterized by comprising: air rremoval means disposed in the conduit for removing entrained air from the ink; booster means connected to the removal means for increasing the air removing ability thereof; and sensor means for sensing an amount of entrained air in the ink in the head and producing a signal when the amount of entrained air exceeds a predetermined value, the booster means being energized by the signal.
Claim 2
Dependent Claim
90 words
An ink ejection apparatus including an ink reservoir, an ink ejection head and a conduit connecting the reservoir to the head, characterized by comprising: air rremoval means disposed in the conduit for removing entrained air from the ink; booster means connected to the removal means for increasing the air removing ability thereof; and sensor means for sensing an amount of entrained air in the ink in the head and producing a signal when the amount of entrained air exceeds a predetermined value, the booster means being energized by the signal.
Claim 3
Dependent Claim
14 words
An apparatus as in claim 1, in which the booster means comprises a heater.
Claim 4
Dependent Claim
61 words
An apparatus as in claim 1, in which the ink ejection head comprises a piezoelectric vibrator, an amplitude of oscillation of the vibrator increasing as the amount of entrained air in the ink in the head increase, the sensor means being constructed to measure the amplitude of oscillation and produce the signal when the amplitude of oscillation exceeds a predetermined value.
Claim 5
Dependent Claim
82 words
An apparatus as in claim 1, in which the air removal means comprises a container having an inlet and an outlet and partition means provided in the container for defining a plurality of ink flow chambers, the partition means being formed with openings such that ink flows from the inlet through all of the ink flow chambers to the outlet, the container defining an air collection chamber above the ink flow chambers, the ink flow chambers communicating with the air collection chamber.
Claim 6
Dependent Claim
45 words
An apparatus as in claim 4, in which the partition means comprises first and second sets of upwardly extending walls, the first walls alternating with the second walls, the first walls being formed with upper openings and the second walls being formed with lower openings.
Claim 7
Dependent Claim
33 words
An apparatus as in claim 4, further comprising check valve means disposed between the air collection chamber and the atmosphere for allowing air flow only from the air collection chamber to the atmosphere.
Claim 8
Dependent Claim
16 words
An apparatus as in claim 6, in which the check valve means comprises a constricted tube.
Claim 9
Dependent Claim
18 words
An apparatus as in claim 4, in which the partition means comprises a plurality of upwardly extending walls.
Claim 10
Dependent Claim
12 words
An apparatus as in claim 8 in which the walls are circular.
Claim 11
Dependent Claim
19 words
An apparatus as in claim 8, in which the walls extend straight upwardly from a bottom of the container.
Claim 12
Dependent Claim
20 words
An apparatus as in claim 8, in which the walls extend diagonally upwardly from a side wall of the container.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-16 | 1985-05-18 | 1985-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-16 | 1989-05-18 | 1989-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-16 | 1993-05-18 | 1993-11-17 | $7700.00 | Window Closed / Lapsed |