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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
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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 Cited

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

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