Sheet feeder and image forming apparatus incorporating the sheet feeder

Patent metadata

Field	Value
Publication number	US-2016334748-A1
Application number	US-201615151566-A
Country	US
Kind code	A1
Filing date	May 11, 2016
Priority date	May 15, 2015
Publication date	Nov 17, 2016
Grant date	—

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 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.

2 . The sheet feeder according to claim 1 ,
wherein the support supports the pressing unit at a support position and the pressing unit contacts the sheet feeding unit at a contact position, and wherein 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 1 ,
wherein the support supports the pressing unit at a support position and the pressing unit contacts the sheet feeding unit at a contact position, and wherein the support position is located downstream from the contact position in a sheet conveying direction.

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

8 . 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.

9 . 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.

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

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

12 . The sheet feeder according to claim 11 ,
wherein the pressing unit 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 8 ,
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 contacts the sheet at a position between a contact position where the pressing unit contacts the sheet feeding unit via the sheet and a contact position where the sheet separating unit contacts 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 pressing unit when the pressing unit contacts the sheet feeding unit.

17 . The sheet feeder according to claim 15 ,
wherein, after the sheet conveyed from the bottom plate is pressed by the pressing unit against the sheet feeding unit, the sheet contacts the sheet feeding unit and the friction unit, and then is separated and fed by the sheet feeding unit and the sheet separating 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 to convey the sheet toward the image forming device.

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

• G03G15/6529 Primary

  Transporting (G03G15/6555 takes precedence) · CPC title

• 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