Sheet feeder and image forming apparatus incorporating the sheet feeder

Patent metadata

Field	Value
Publication number	US-9856099-B2
Application number	US-201615151566-A
Country	US
Kind code	B2
Filing date	May 11, 2016
Priority date	May 15, 2015
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

A sheet feeder, which is included in an image forming apparatus, includes a sheet feeding unit to feed a sheet, a sheet separating unit disposed opposite the sheet feeding unit to separate the sheet together with the sheet feeding unit, a bottom plate on which the sheet is loaded, a pressing unit having a leading end and movably disposed between the bottom plate and the sheet separating unit, and a support to rotatably support the pressing unit such that the leading end of the pressing unit contacts and separates from the sheet feeding unit.

First claim

What is claimed is:

1. A sheet feeder comprising:
a sheet feeding unit configured to feed a sheet;
a sheet separating unit opposite the sheet feeding unit configured to separate the sheet together with the sheet feeding unit;
a bottom plate configured to have the sheet loaded thereon;
a pressure plate having a leading end, the pressure plate is movably disposed between the bottom plate and the sheet separating unit; and
a support configured to rotatably support the pressure plate such that the leading end of the pressure plate contacts and separates from the sheet feeding unit.

2. The sheet feeder according to claim 1 , wherein,
the support is configured to support the pressure plate at a support position
the pressure plate is configured to contact the sheet feeding unit at a contact position, and
the support position is located upstream from the contact position in a sheet conveying direction.

3. The sheet feeder according to claim 2 ,
wherein, in a vertical direction, the support position is located at an upper side from a tangent line at the contact position.

4. The sheet feeder according to claim 2 ,
wherein, in a vertical direction, the support position is located at a lower side from a tangent line at the contact position.

5. The sheet feeder according to claim 2 ,
wherein, in a vertical direction, the support position is located near a tangent line at the contact position.

6. The sheet feeder according to claim 2 ,
wherein, in a vertical direction, the support position is located at a lower side from a tangent line at the contact position.

7. The sheet feeder according to claim 2 ,
wherein, in a vertical direction, the support position is located near a tangent line at the contact position.

8. The sheet feeder according to claim 1 ,
wherein the support is configured to support the pressure plate at a support position
the pressure plate is configured to contact the sheet feeding unit at a contact position, and
the support position is located downstream from the contact position in a sheet conveying direction.

9. The sheet feeder according to claim 8 ,
wherein the support position is located at an upper side from a tangent line in a vertical direction.

10. The sheet feeder according to claim 1 ,
wherein an axial width of the pressure plate is greater than an axial width of the sheet feeding unit.

11. The sheet feeder according to claim 1 , further comprising:
a rotary body; and
a biasing unit mounted on the support,
wherein, the support is configured to rotatably support the rotary body, and
the leading end of the pressure plate is configured to contact the sheet feeding unit by attaching the pressure plate to the rotary body and biasing the rotary body by the biasing unit.

12. The sheet feeder according to claim 11 ,
wherein the pressure plate and the rotary body are formed in a single unit.

13. The sheet feeder according to claim 12 ,
wherein the biasing unit is disposed at both axial ends of the sheet separating unit.

14. The sheet feeder according to claim 11 ,
wherein the biasing unit is disposed at both axial ends of the sheet separating unit.

15. The sheet feeder according to claim 11 , further comprising a friction unit attached to the rotary body and disposed at both axial ends of the sheet feeding unit,
wherein the friction unit is configured to contact the sheet at a position between a contact position where the pressure plate is configured to contact the sheet feeding unit via the sheet and a contact position where the sheet separating unit is configured to contact the sheet feeding unit via the sheet.

16. The sheet feeder according to claim 15 ,
wherein the friction unit has a height beyond an extension line on a contact face of the sheet feeding unit with the pressure plate when the pressure plate contacts the sheet feeding unit.

17. The sheet feeder according to claim 15 ,
wherein, the sheet feeding unit and the friction unit are configured to contact, separate, and feed the sheet after the sheet conveyed from the bottom plate is pressed by the pressure plate against the sheet feeding unit.

18. The sheet feeder according to claim 1 ,
wherein the sheet separating unit includes a torque limiter.

19. An image forming apparatus comprising:
an image forming device to form an image on a sheet; and
the sheet feeder according to claim 1 configured to convey the sheet toward the image forming device.

20. A sheet feeder comprising:
a sheet feeding roller configured to feed a sheet;
a sheet separating roller opposite the sheet feeding roller configured to separate the sheet together with the sheet feeding roller;
a bottom plate configured to have the sheet loaded thereon;
a pressure plate having a leading end, the pressure plate is movably disposed between the bottom plate and the sheet separating unit; and
a support shaft configured to rotatably support the pressure plate such that the leading end of the pressure plate contacts and separates from the sheet feeding roller.

Assignees

• Aoyama Jumpei
• Nishida Hajime
• Nonaka Manabu
• Sugita Junichi
• Ueda Kenji
• Ricoh Co Ltd

Inventors

• Aoyama Jumpei
• Nishida Hajime
• Nonaka Manabu
• Sugita Junichi
• Ueda Kenji

Classifications

• B65H3/06

  Rollers or like rotary separators {(B65H3/42 takes precedence)} · CPC title

• B65H3/5223 Primary

  Retainers of the pad-type, e.g. friction pads · CPC title

• G03G15/6511 Primary

  Feeding devices for picking up or separation of copy sheets · CPC title