US 9,284,141 B2Granted

Sheet feeding apparatus and image forming apparatus

AssigneeCanon Kabushiki Kaisha

InventorKazuhiro Kosuga

Life of this patent

Estimating the term…

Loading patent…

Abstract

A sheet feeding roller 101 which feeds a sheet S stacked on a sheet supporting plate 110 capable of being lifted and lowered is swingably supported at a swing end of a sheet feeding roller supporting arm 104 which is arranged swingably in an up-and-down direction and a roller biasing member applies a force to the sheet feeding roller supporting arm in a direction that the sheet feeding roller is pressed to sheets S stacked on a sheet stack tray. A swing fulcrum 104a is arranged in a range between a tangential line of the sheet feeding roller at the upstreammost pressing position against the sheet feeding direction and a tangential line of the sheet feeding roller at the downstreammost pressing position out of pressing positions where the sheet feeding roller is pressed to the sheets as being varied in accordance with a sheet stacking state of the sheets.

Claims10

Dependent claims

A sheet feeding apparatus, comprising:

a sheet storage portion which includes a sheet stack tray which is swingable in an up-and-down direction;
a feeding roller which is arranged above the sheet stack tray and which feeds an uppermost sheet stacked on the sheet stack tray;
a support member which is swingable in an up-and-down direction about a swing fulcrum and which supports the feeding roller to be swingable at a swing end;
and
a roller biasing member which applies a force to the support member in a direction in which the feeding roller is pressed to the uppermost sheet stacked on the sheet stack tray;
and
a separation roller, disposed downstream of the sheet stack tray in a sheet feeding direction, which is pressed against feeding roller to form a separation portion with the feeding roller that separates sheets one by one, wherein
when the feeding roller presses to contact with the uppermost sheet stacked in the sheet storage portion, the sheet storage portion is disposed so as that a downstream end in a sheet conveyance direction of the uppermost sheet is positioned adjacent a lowest point of the feeding roller, and
a biasing direction of the roller biasing member is configured so that a contacting and pressing position between the sheet and a peripheral surface of the feeding roller changes between both an upstream side and downstream side for the lowest point of the feeding roller in the sheet conveyance direction according to a stacking amount of the sheet stacked in the sheet storage portion.

6 more elements

An image forming apparatus which includes a sheet feeding apparatus which upwardly swings a sheet stack tray to have an uppermost sheet pressed to a feeding roller when performing sheet feeding, and an image forming portion which forms an image on a sheet fed from the sheet feeding apparatus, the sheet feeding apparatus comprising:

a sheet storage portion which includes the sheet stack tray which is swingable in an up-and-down direction of sheet stacking;
a feeding roller which is arranged above the sheet stack tray and which feeds an uppermost sheet stacked on the sheet stack tray;
a support member which is swingable in an up-and-down direction about a swing fulcrum and which supports the feeding roller to be swingable at a swing end;
and
a roller biasing member which applies a force to the support member in a direction in which the feeding roller is pressed to the uppermost sheet stacked on the sheet stack tray;
and
a separation roller, disposed downstream of the sheet stack tray in the sheet feed direction, which is pressed against feeding roller to form a separation portion with the feeding roller that separates the sheets one by one, wherein
when the feeding roller presses to contact with the sheet stacked in the sheet storage portion, the sheet storage portion is disposed so as that a downstream end of the sheet in a sheet conveyance direction positions near a lowest point of the feeding roller, and
a biasing direction of the roller biasing member is configured so that a contacting and pressing position between the sheet and a peripheral surface of the feeding roller changes between both an upstream side and downstream side for the lowest point of the feeding roller in the sheet conveyance direction according to a stacking amount of the sheet stacked in the sheet storage portion.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 14/116,856Filed 25 Jun 2012
Priority: JP 2011-14034824 Jun 2011
Published: US 2014/0070481 A113 Mar 2014
Granted: 15 Mar 2016
Term ends: Not estimatedThe source records don’t support an estimate.

Classification8 codes

B65H 5/06
Feeding articles separated from piles; Feeding articles to machines: by rollers or balls, e.g. between rollers
B65H 1/14
With means for advancing the articles to present the articles to the separating device: comprising positively-acting mechanical devices
B65H 1/24
With means for advancing the articles to present the articles to the separating device: with means for relieving or controlling pressure of the pile
B65H 3/0684
Rollers or like rotary separators: on moving support, e.g. pivoting, for bringing the roller or like rotary separator into contact with the pile