Sheet feeding device

• US 20050253325A1
• Filed: 05/16/2005
• Published: 11/17/2005
• Est. Priority Date: 05/14/2004
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Hirabayashi, Kenichi, Ogaya, Shunpei
• Granted Patent: US 7,407,158 B2
• Time in Patent Office: Days
• US Class Current: 271/119
• CPC Class Codes: B65H 2404/1112 D-shape
• CPC Class Codes: B65H 3/0638 Construction of the rollers or like rotary separators B65H3/0615 takes precedence; construction of feed or guide rollers B65H27/00
• CPC Class Codes: B65H 3/5238 Retainers of the pad-type, e.g. friction pads

Abstract

A sheet feeding roller has an outer circumferential face which includes a generally flat portion and a curved portion. A first pivotable member is movable between a first position and a second position in accordance with the rotation of the sheet feeding roller. The first pivotable member has a first contact face and an extended member extended from a free end portion of the first pivotable member toward a downstream side of a sheet feeding direction. The first pivotable member is moved to the second position when a sheet medium is placed between the sheet feeding roller and the first pivotable member. The first pivotable member is returned to the first position when a trailing end of the sheet medium faces the flat portion of the sheet feeding roller while the extended member of the first pivotable member comes in contact with the sheet medium.

Claims

1. A sheet feeding device, comprising:

a sheet feeding roller having an outer circumferential face which includes a generally flat portion and a curved portion;

a first pivotable member, movable between a first position and a second position in accordance with the rotation of the sheet feeding roller, the first pivotable member comprising a first contact face and an extended member extended from a free end portion of the first pivotable member toward a downstream side of a sheet feeding direction, wherein;

the first pivotable member is moved to the second position when a sheet medium is placed between the sheet feeding roller and the first pivotable member; and

the first pivotable member is returned to the first position when a trailing end of the sheet medium faces the flat portion of the sheet feeding roller while the extended member of the first pivotable member comes in contact with the sheet medium.

2. The sheet feeding device as set forth in claim 1, further comprising a second pivotable member, movable between a third position and a fourth position in accordance with the rotation of the sheet feeding roller, the second pivotable member comprising a second contact face, wherein:

the second pivotable member is placed in the third position and the first pivotable member is placed in the first position when no sheet medium is placed between the sheet feeding roller and the first pivotable member, so that a gap is formed between the flat portion of the sheet feeding roller and the second contact face while the flat portion of the sheet feeding roller and the first contact face are extended substantially perpendicularly to each other;

the second pivotable member is moved to the fourth position and the first pivotable member is moved to the second position when the sheet medium is placed between the sheet feeding roller and the first pivotable member while the first contact-face and the second contact face press the sheet medium against the curved portion of the sheet feeding roller.

3. The sheet feeding device as set forth in claim 1, wherein the first contact face and the extended member are extended substantially perpendicular to each other.

4. The sheet feeding device as set forth in claim 1, wherein the extended member has a curved contact face.

5. The sheet feeding device as set forth in claim 2, wherein a pressing force of the second pivotable member is less than a pressing force of the first pivotable member.

6. The sheet feeding device as set forth in claim 2, wherein the extended member is shaped and positioned such that the first pivotable member is gradually returned to the first position when the trailing end of the sheet medium is downstream of the second pivotable member.

7. A sheet feeding device, comprising:

an inlet section, adapted to receive at least one sheet medium;

a sheet feeding roller, having an outer circumferential face which includes a generally flat portion and a curved portion;

a first pivotable member, comprising an extended member extended from a free end portion thereof toward a downstream side in a sheet feeding direction;

a second pivotable member disposed upstream of the inlet section in the sheet feeding direction relative to the first pivotable member, so as to oppose the outer circumferential face of the sheet feeding roller through the inlet section, so that the sheet medium is elastically pressed against the outer circumferential face of the sheet feeding roller; and

a control mechanism operable to pivot the second pivotable member so as to be away from the sheet feeding roller when the flat portion of the sheet feeding roller opposes the second pivotable member through the inlet section.

8. The sheet feeding device as set forth in claim 7, wherein the extended member has a curved contact face.

9. The sheet feeding device as set forth in claim 7, wherein the first pivotable member is adapted to elastically contact the curved portion of the sheet feeding roller.

10. The sheet feeding device as set forth in claim 7, wherein a pressing force of the second pivotable member is less than a pressing force of the first pivotable member.

11. The sheet feeding device as set forth in claim 7, further comprising

a frictional stopper disposed upstream of the inlet section in the sheet feeding device and comprising a face having a higher frictional coefficient than any other portion in the inlet section.

12. The sheet feeding device as set forth in claim 11, wherein the frictional stopper is a sheet member provided on a bottom wall of the inlet section.

13. The sheet feeding device as set forth in claim 11, wherein the frictional stopper comprises saw-shaped projections formed on a bottom wall of the inlet section.

14. A sheet feeding device comprising:

a sheet feeding roller;

a first pressing member disposed facing the sheet feeding roller, the first pressing member being urged in the pressing direction toward the sheet feeding roller; and

a second pressing member disposed facing the sheet feeding roller upstream from the first pressing member, the first pressing member being urged in a pressing direction toward the sheet feeding roller,

wherein a sheet receiving area is defined between the first pressing member, the sheet feeding roller and the second pressing member; and

wherein when the sheet feeding roller feeds a sheet from the sheet receiving area in a downstream direction, the sheet is pressed against the sheet feeding roller and the first and second pressing members are pushed by the sheet in a direction opposite from the pressing direction, and wherein the first pressing member is structured such that when a trailing end of the sheet is downstream from the second pressing member, the first pressing member is gradually returned in the pressing direction.

15. The sheet feeding device as set forth in claim 14, wherein prior to the sheet feeding roller feeding a sheet, the first pressing member and the second pressing member are disposed substantially perpendicular to each other such that when the first pressing member returns in the pressing direction, the first pressing member serves to align sheets in the sheet receiving area.

16. The sheet feeding device as set forth in claim 14, wherein the first pressing member comprises an extended member extended therefrom on a downstream side thereof, the extended member being shaped and positioned to effect the gradual return of the first pressing member in the pressing direction.

17. The sheet feeding device as set forth in claim 14, wherein a pressing force of the second pressing member is less than a pressing force of the first pressing member.