Method for controlling a sheet feeding device (1) comprising an elevator (2) for a stack of sheets, and an air supply system (3) configured to supply and direct one of more air streams towards an upper region (4) of the sheet feeding device for floating a plurality of upper sheets of the stack of sheets, wherein the elevator comprises a vertically movable support (5) for supporting the stack of sheets from below, wherein the sheet feeding device comprises an optical sensor (6) positioned adjacent the floated sheets for measuring light reflected from the floated sheets at a plurality of different heights, wherein the method comprises the steps of: continuously deriving from the optical sensor a density reading (DR) indicating the density of sheets floated, continuously deriving an average density (AD) based on a plurality of density readings, continuously deriving an upper density limit (UDL) based on the average density multiplied by a predetermined upper density limit factor (UDLF), continuously deriving a lower density limit (LDL) based on the average density multiplied by a predetermined lower density limit factor (LDLF), adjusting a first operating parameter (OP) of the sheet feeding device should the density reading exceed the upper density limit, wherein the adjustment of the first operating parameter is such as to decrease the density of floated sheets, and adjusting the first operating parameter of the sheet feeding device should the density reading subceed the lower density limit, wherein the adjustment of the first operating parameter is such as to increase the density of floated sheets. Also, a sheet feeding device connected to a controller configured to operate according to this method.

Method for controlling a sheet feeding device (1) comprising an elevator (2) for a stack of sheets, and an air supply system (3) configured to supply and direct one of more air streams towards an upper region (4) of the sheet feeding device for floating a plurality of upper sheets of the stack of sheets, wherein the elevator comprises a vertically movable support (5) for supporting the stack of sheets from below, wherein the sheet feeding device comprises an optical sensor (6) positioned adjacent the floated sheets for measuring light reflected from the floated sheets at a plurality of different heights, wherein the method comprises the steps of: continuously deriving from the optical sensor a density reading (DR) indicating the density of sheets floated, continuously deriving an average density (AD) based on a plurality of density readings, continuously deriving an upper density limit (UDL) based on the average density multiplied by a predetermined upper density limit factor (UDLF), continuously deriving a lower density limit (LDL) based on the average density multiplied by a predetermined lower density limit factor (LDLF), adjusting a first operating parameter (OP) of the sheet feeding device should the density reading exceed the upper density limit, wherein the adjustment of the first operating parameter is such as to decrease the density of floated sheets, and adjusting the first operating parameter of the sheet feeding device should the density reading subceed the lower density limit, wherein the adjustment of the first operating parameter is such as to increase the density of floated sheets. Also, a sheet feeding device connected to a controller configured to operate according to this method.

A medium feeding apparatus includes a pickup roller that feeds a medium from a medium mount section. A support member supports a pickup roller and swings around a swing axis to switch between a feeding position and a non-feeding position. A separation roller separates the medium from other media. A feed roller feeds the medium toward the downstream end. The separation and feed rollers are disposed downstream of the pickup roller. A control section controls a position of the support member. After the pickup roller and the feed roller start rotating, when the control section determines that the separation roller stops rotating or returns the medium by rotating in a reverse direction, based on a detection signal from a rotation sensing section configured to detect rotation of the separation roller, the control section causes the support member to switch from the feeding position to the non-feeding position.

A medium feeding apparatus includes a pickup roller that feeds a medium from a medium mount section. A support member supports a pickup roller and swings around a swing axis to switch between a feeding position and a non-feeding position. A separation roller separates the medium from other media. A feed roller feeds the medium toward the downstream end. The separation and feed rollers are disposed downstream of the pickup roller. A control section controls a position of the support member. After the pickup roller and the feed roller start rotating, when the control section determines that the separation roller stops rotating or returns the medium by rotating in a reverse direction, based on a detection signal from a rotation sensing section configured to detect rotation of the separation roller, the control section causes the support member to switch from the feeding position to the non-feeding position.

A control section of a recording apparatus is configured to execute control of overlapping transportation in which a preceding medium and a following medium are transported in a state in which a rear end region of the preceding medium and a leading end region of the following medium overlap at least in a partial section in an upper transport route, and determines an overlapping dimension Lk that is a dimension, by which the rear end region of the preceding medium and the leading end region of the following medium overlap, in accordance with a route dimension Ld from a third feed roller pair to an edge of an introducing port in a second direction, when executing the control of the overlapping transportation.

In an example of the disclosure, a driver correction specification is calculated based upon a time differential between a first sensor detection of a first portion of a leading edge of a media sheet and second sensor detection of a second portion of the leading edge. The driver correction specification is for causing skew correction of the media sheet as the media sheet moves along a media path to impact a blocker element. The driver is caused to operate according to the calculated driver correction specification.

A sheet stacking part stacks sheets. A first roller applies a force in a conveyance direction to an uppermost sheet among sheets stacked on the sheet stacking part by rotating in a forward direction. A second roller is separated from the first roller on the downstream side in the conveyance direction. The second roller applies the force in the conveyance direction to the uppermost sheet by rotating in the forward direction. A controller controls rotation of the first roller and the second roller so that a second main operation is performed after a first main operation. The first main operation is an operation of rotating only the first roller of the first roller and the second roller in the forward direction. The second main operation is an operation of rotating both the first roller and the second roller in the forward direction.

An image forming apparatus includes a paper feeding cassette, a first conveying unit, a lift mechanism, a motor, a second conveying unit, and a control unit. The controller drives the motor and, if a value indicating a movement amount of the tray moving from when the lift mechanism starts the lifting of the tray until when a position of the top part reaches a first position is a first value, matches a position of the first conveying unit, which comes into contact with the top part to thereby rise together with the tray, with a second position and, if the value indicating the movement amount is a second value larger than the first value, matches the position of the first conveying unit, which comes into contact with the top part to thereby rise together with the tray, with a third position lower than the second position.

A medium feeding device includes a medium placing portion, a feeding roller that feeds paper, a medium movement detecting portion that is positioned on a placing region of the paper of the medium placing portion in a medium feeding direction and is capable of detecting movement of the paper being fed in a width direction intersecting the medium feeding direction, and a controller that stops feeding of the paper in a case in which a physical quantity relating to movement of paper in the width direction exceeds a predetermined threshold based on a detected result by the medium movement detecting portion.

A medium feeding device includes a medium placing portion, a feeding roller that feeds paper, a medium movement detecting portion that is positioned on a placing region of the paper of the medium placing portion in a medium feeding direction and is capable of detecting movement of the paper being fed in a width direction intersecting the medium feeding direction, and a controller that stops feeding of the paper in a case in which a physical quantity relating to movement of paper in the width direction exceeds a predetermined threshold based on a detected result by the medium movement detecting portion.