US4834277A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Paper feeding in printers
Assignee: Vodafone GmbH
•
Filing: 1987-03-04
•
Granted: 1989-05-30
•
Expires: 2007-03-04
Abstract
Abstract The paper feeder incudes an upstream friction roller pair for single sheet feeding, a pushing tractor for endless sheet feeding, and a common downstream (behind the platen) friction roller pair. Each pair has one roller mounted on a pivot lever and the two levers linkedly held in a spring biased linkage such that consistently the downstream roller pair exert a smaller friction force while rotating at a higher speed.
Inventors
- 👤 Guenter Gomoll
- 👤 Wolfgang Hauslaib
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:28
CPC Classifications
B; B41; B41J; B41J11/00; B41J11/48; B41J11/26; B41J11/30; B41J13/00; B41J13/10; B41J13/103
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
184 words
Paper feeder for printers which include a print platen mounted in a frame, comprising in combination: a first friction roller pair for single sheet feeding arranged upstream of the platen with respect to paper flow past the platen; a thrust or pushing tractor for feeding endless sheet material towards the printing platen and likewise arranged upstream from said printing platen and operationally in parallel to said first friction roller pair; a second friction roller pair for both single sheets and endless sheets and being arranged downstream from the printing platen with respect to paper flow; one roller of each pair being journalled in said printer frame for rotation thereon; a first pivot lever for mounting the other roller of the first pair; a second pivot lever mounting the other roller of the second pair; and spring-biased linkage means interconnecting the first and second levers such that the pressure of the roller on the first lever against the one roller of the first pair is consistently larger than the pressure of the roller on the second lever against the one roller of the second pair.
Claim 2
Dependent Claim
184 words
Paper feeder for printers which include a print platen mounted in a frame, comprising in combination: a first friction roller pair for single sheet feeding arranged upstream of the platen with respect to paper flow past the platen; a thrust or pushing tractor for feeding endless sheet material towards the printing platen and likewise arranged upstream from said printing platen and operationally in parallel to said first friction roller pair; a second friction roller pair for both single sheets and endless sheets and being arranged downstream from the printing platen with respect to paper flow; one roller of each pair being journalled in said printer frame for rotation thereon; a first pivot lever for mounting the other roller of the first pair; a second pivot lever mounting the other roller of the second pair; and spring-biased linkage means interconnecting the first and second levers such that the pressure of the roller on the first lever against the one roller of the first pair is consistently larger than the pressure of the roller on the second lever against the one roller of the second pair.
Claim 3
Dependent Claim
17 words
Paper feeder as in claim 1, said linkage means including spring means for biasing the second lever.
Claim 4
Dependent Claim
31 words
Paper feeding as in claim 1, said linkage means including a spring-biased intermediate lever for mounting the second lever, and a coupling spring interconnecting the intermediate lever and the first lever.
Claim 5
Dependent Claim
43 words
Paper feeder as in claim 1, said second lever abutting a stop when urging the roller it carries against the one of the first pair, the stop oriented at right angles to a direction between axes of the rollers of the first pair.
Claim 6
Dependent Claim
24 words
Paper feeder as in claim 1, the other roller of the second pair being mounted on an articulated drive shaft permitting also axial displacement.
Claim 7
Dependent Claim
27 words
Paper transport as in claim 6 wherein one roller of each pair is covered with rubber, the other one being a synthetic roller with a smooth surface.
Claim 8
Dependent Claim
24 words
Paper transport as in claim 1 wherein one roller of each pair is covered with rubber the other one is a knurled steel roller.
Claim 9
Dependent Claim
11 words
Paper transport as in claim 1 wherein all rollers are driven.
Claim 10
Dependent Claim
16 words
Paper feeder as in claim 1, pivot axes of the levers are parallel to the platen.
References Cited (Backward Citations)
US3330458A
Cited
US3561660A
Cited
US3753483A
Cited
US4272001A
Cited
US4564305A
Cited
EP0123310A2
Cited
US4606663A
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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) | 1992-05-29 | 1992-11-28 | 1993-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-05-29 | 1996-11-28 | 1997-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-05-29 | 2000-11-28 | 2001-05-30 | $7700.00 | Window Closed / Lapsed |