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US4395034A Expired / Lapsed US ⏱️ 0.0 years remaining

Sheet feeding device

Assignee: Minolta Co Ltd
•
Filing: 1981-05-04
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Granted: 1983-07-26
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Expires: 2001-05-04
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Abstract

Abstract A sheet feeding device comprises a cassette for holding a stack of sheets, feeding means for longitudinally advancing the uppermost sheet of the stack from the cassette in pressing contact with the sheet at approximately the longitudinal medial axis of the sheet with respect to the feeding direction, separating pawl members for separating the uppermost sheet from the other sheets by engaging the uppermost sheet at its leading opposite corners to thereby temporarily restrain the uppermost sheet from advancing, and pressure members for pressing the uppermost sheet at its opposite side portions to a predetermined extent. The pressure members are retractable from the pressing position in accordance with the resilient force of the sheet when the advancing sheet is buckled by engagement with the separating pawl members.

Inventors

  • 👤 Kazuyuki Fukui

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 17:30
CPC Classifications
B; B65; B65H; B65H1/00; B65H1/26; B65H1/266; B65H1/04; B65H3/00; B65H3/46; B65H3/54

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 136 words
A sheet feeding device comprising: a casette for holding a stack of sheets; feeding means for longitudinally advancing from the cassette the uppermost sheet of the stack in pressing contact with the sheet at approximately its medial longitudinal axis; separating pawl members for separating the uppermost sheet from the other sheets by engaging the uppermost sheet at its opposite leading corners; and pressure means for pressing the uppermost sheet at its opposite side portions and being retractable, at least in part independently of any moement of said pawl members from the pressing position in response to the resilient force of the uppermost sheet when the uppermost sheet is bent by its advance in engagement with the separating pawl members; whereby the sheet is properly discharged regardless of the size or thickness or resiliency of the sheet.
Claim 2
Dependent Claim 136 words
A sheet feeding device comprising: a casette for holding a stack of sheets; feeding means for longitudinally advancing from the cassette the uppermost sheet of the stack in pressing contact with the sheet at approximately its medial longitudinal axis; separating pawl members for separating the uppermost sheet from the other sheets by engaging the uppermost sheet at its opposite leading corners; and pressure means for pressing the uppermost sheet at its opposite side portions and being retractable, at least in part independently of any moement of said pawl members from the pressing position in response to the resilient force of the uppermost sheet when the uppermost sheet is bent by its advance in engagement with the separating pawl members; whereby the sheet is properly discharged regardless of the size or thickness or resiliency of the sheet.
Claim 3
Dependent Claim 27 words
A sheet feeding device as claimed in claim 1, including side plates disposed within the cassette, said pressure means being mounted to each of said side plates.
Claim 4
Dependent Claim 40 words
A sheet feeding device as claimed in claim 2, said pressure means comprising a first arm member pivotally attached to each of said side plates and a pressure member mounted on a free end of each of said arm members.
Claim 5
Dependent Claim 18 words
A sheet feeding device as claimed in claim 3, wherein said pressure member comprises a rotatable roller member.
Claim 6
Dependent Claim 26 words
A sheet feeding device as claimed in claim 3, wherein said pressure member has a curved underface which contacts said uppermost sheet with relatively low resistance.
Claim 7
Dependent Claim 46 words
A sheet feeding device as claimed in claim 3, including second arm members mounted to respective side plates for swinging about the pivot axis of said first arm members, said separating pawl members being formed on the free end of each of said second arm members.
Claim 8
Dependent Claim 17 words
A sheet feeding device as claimed in claim 1, wherein said pressure means is longitudinally adjustably movable.
Claim 9
Dependent Claim 61 words
A sheet feeding device as claimed in claim 7, including side plates disposed within said cassette, said pressure means being mounted to each of said side plates and including an arm member pivotally attached to each of said side plates as to be longitudinally adjustably movable and a pressure member mounted on a free end of each of said arm members.
Claim 10
Dependent Claim 56 words
A sheet feeding device as claimed in claim 8, wherein each of said side plates has a longitudinal horizontal slot and each of said arm members includes a pivot longitudinally slidably engaging a respective slot and plurality of recesses formed at predetermined positions along each of said slots for selectively engaging and fixedly positioning respective pivots.
Claim 11
Dependent Claim 17 words
A sheet feeding device as claimed in claim 8, wherein said pressure member includes rotatable roller member.
Claim 12
Dependent Claim 28 words
A sheet feeding device as claimed in claim 8, wherein said pressure member has a curved underface which contacts the uppermost sheet with relatively low longitudinal sliding resistance.
Claim 13
Dependent Claim 110 words
A sheet feeding mechanism comprising; means for holding a stack of sheets; advancing means for applying a longitudinal advancing force to the uppermost sheet of said stack in the vicinity of the medial longitudinal axis of said sheet; restraining means for releasably restraining the longitudinal advance of the leading corners of said uppermost sheet whereby to buckle said uppermost sheet during the initial advance thereof; and pressure members bearing on the side borders of said uppermost sheet and being movable independently, at least in part, of movement of said restraining means, to a raised position in response to the buckling of the portions of said sheets underlying said pressure members.
Claim 14
Dependent Claim 110 words
A sheet feeding mechanism comprising; means for holding a stack of sheets; advancing means for applying a longitudinal advancing force to the uppermost sheet of said stack in the vicinity of the medial longitudinal axis of said sheet; restraining means for releasably restraining the longitudinal advance of the leading corners of said uppermost sheet whereby to buckle said uppermost sheet during the initial advance thereof; and pressure members bearing on the side borders of said uppermost sheet and being movable independently, at least in part, of movement of said restraining means, to a raised position in response to the buckling of the portions of said sheets underlying said pressure members.
Claim 15
Dependent Claim 20 words
The mechanism of claim 12 wherein said restraining means comprises a projection overlying each of said uppermost sheet leading corners.
Claim 16
Dependent Claim 27 words
The mechanism of claim 12 including a pair of arms swingable about a transverse axis, said pressure members being mounted proximate the free ends of respective arms.
Claim 17
Dependent Claim 12 words
The mechanism of claim 12 wherein said pressure members are longitudinally adjustable.

References Cited (Backward Citations)

US1960482A Cited
US3278181A Cited
US3497206A Cited
US3647204A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-07-25 1987-01-24 1987-07-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-07-25 1991-01-24 1991-07-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-07-25 1995-01-24 1995-07-26 $7700.00 Window Closed / Lapsed

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