US4961076A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reliability improvement for ink jet pens
Assignee: HP Inc
•
Filing: 1988-12-30
•
Granted: 1990-10-02
•
Expires: 2008-12-30
Abstract
Abstract An ink jet pen includes an ink reservoir for containing ink and a catchbasin coupled to the reservoir by an orifice for containing ink displaced from the reservoir by environmental conditions. Also coupling the reservoir and catchbasin is an ink return mechanism that permits substantially all of the ink that may be displaced to the catchbasin to be returned to the reservoir regardless of the pen's orientation.
Inventors
- 👤 Bruce Cowger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 04:22
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/17; B41J2/175; B41J2/17503; B41J2/17553; B41J2/17513; B41J2/19
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
103 words
An ink jet pen comprising: an ink reservoir for containing ink; a drop ejector for ejecting ink droplets from the ink reservoir to a printing medium; an orifice for introducing air bubbles to the ink reservoir to moderate the reservoir underpressure caused by the ejection of ink therefrom, and for permitting ink to be displaced from the reservoir when air therein expands; a catchbasin coupled to the reservoir through said orifice for receiving said displaced ink; and ink pickup means coupling the catchbasin to the ink reservoir for returning ink from the catchbasin to the reservoir when the air in the catchbasin contracts.
Claim 2
Dependent Claim
103 words
An ink jet pen comprising: an ink reservoir for containing ink; a drop ejector for ejecting ink droplets from the ink reservoir to a printing medium; an orifice for introducing air bubbles to the ink reservoir to moderate the reservoir underpressure caused by the ejection of ink therefrom, and for permitting ink to be displaced from the reservoir when air therein expands; a catchbasin coupled to the reservoir through said orifice for receiving said displaced ink; and ink pickup means coupling the catchbasin to the ink reservoir for returning ink from the catchbasin to the reservoir when the air in the catchbasin contracts.
Claim 3
Dependent Claim
29 words
The ink jet pen of claim 1 in which the ink pickup means comprises a plurality of tubes extending from the ink reservoir into different portions of the catchbasin.
Claim 4
Independent Claim
70 words
A method of operating an ink jet pen that includes an ink reservoir, a catchbasin and an orifice coupling the reservoir and catchbasin, comprising the steps: flowing ink from the reservoir to the catchbasin through the orifice when air in the reservoir expands; and flowing substantially all of the ink from the catchbasin back to the reservoir when air in the reservoir contracts regardless of the orientation of the pen.
Claim 5
Independent Claim
70 words
A method of operating an ink jet pen that includes an ink reservoir, a catchbasin and an orifice coupling the reservoir and catchbasin, comprising the steps: flowing ink from the reservoir to the catchbasin through the orifice when air in the reservoir expands; and flowing substantially all of the ink from the catchbasin back to the reservoir when air in the reservoir contracts regardless of the orientation of the pen.
Claim 6
Independent Claim
105 words
A method of operating an ink jet pen that includes an ink reservoir, a catchbasin and an orifice coupling the reservoir and catchbasin, comprising the steps: displacing ink from the reservoir to the catchbasin through the orifice when air in the reservoir expands; drawing ink from the catchbasin back to the reservoir through the orifice when air in the reservoir contracts and the orifice is wetted by ink in the catchbasin; and drawing ink from the catchbasin back to the reservoir through a means other than said orifice when air in the reservoir contracts and the orifice is not wetted by ink in the catchbasin.
Claim 7
Independent Claim
105 words
A method of operating an ink jet pen that includes an ink reservoir, a catchbasin and an orifice coupling the reservoir and catchbasin, comprising the steps: displacing ink from the reservoir to the catchbasin through the orifice when air in the reservoir expands; drawing ink from the catchbasin back to the reservoir through the orifice when air in the reservoir contracts and the orifice is wetted by ink in the catchbasin; and drawing ink from the catchbasin back to the reservoir through a means other than said orifice when air in the reservoir contracts and the orifice is not wetted by ink in the catchbasin.
References Cited (Backward Citations)
US3296624A
Cited
US3452361A
Cited
US4296421A
Cited
US4313124A
Cited
US4272773A
Cited
US4419678A
Cited
US4422084A
Cited
US4436439A
Cited
US4376283A
Cited
US4342042A
Cited
US4490728A
Cited
US4412232A
Cited
US4509062A
Cited
US4500895A
Cited
US4539568A
Cited
US4571599A
Cited
US4677447A
Cited
US4714937A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-10-01 | 1994-04-02 | 1994-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-01 | 1998-04-02 | 1998-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-01 | 2002-04-02 | 2002-10-02 | $7700.00 | Window Closed / Lapsed |