A paper separation structure arranged in an office machine, comprising: a separating roller set having a separating roller and a shaft, and a pick roller arranged to correspond to the separating roller set and contacted with the separating roller set, wherein the separating roller has a roller frame, a shaft hole is formed in the roller frame for accommodating the shaft, and a rubber layer connected with the pick roller, the shaft hole has a narrow inner diameter at a middle of the shaft hole and a wide inner diameter at opposite ends of the shaft hole to form two swing spaces between the middle of the shaft hole and opposite ends of the shaft hole, the roller frame and the rubber layer are swung about a joint between the middle of the shaft hole and the shaft.

In the paper feeding roller, a shaft body has a cantilever structure supported at one end, and an elastic layer includes a supported end and a free end on both ends along a rotation axis, wherein an outer diameter of the free end in a cross section orthogonal to the rotational axis is greater than that of the supported end, and an area including the free end has a widened bottom part having an outer diameter which widens in a linear or inner convex manner approaching the free end along the rotation axis. The paper feeding device includes a feed roller rotationally driven and conveying paper, and a retard roller pressed against the feed roller, affixed with a torque limiter, and suppressing double feeding of paper. At least one of the feed roller and the retard roller is formed as the paper feeding roller.

An image processing apparatus includes: a support surface configured to support a sheet, a sheet feeding roller configured to feed the sheet in a conveying direction, a separation member for separating the sheet one by one and positioned downstream of the sheet feeding roller in the conveying direction, and a regulating member displaceable between a first position where the regulating member abuts against a distal end of the sheet supported by the support surface to regulate passage of the sheet in the conveying direction between the sheet feeding roller and the separation member and a second position that is farther from a conveyance path than the first position and that allows passage of the sheet in the conveying direction. The regulating member has a wall surface that abuts against the distal end of the sheet and includes at least one protrusion on the wall surface.

An image forming apparatus includes a sheet container accommodating a recording medium therein, a sheet separating feeder including a sheet feeding body and a sheet separating body, an image forming part, and a bend applier. The sheet feeding body feeds the recording medium along with a surface movement thereof while the recording medium contacting the surface thereof. The sheet separating body forms a sheet separation nip region with the sheet feeding body and sandwiches the recording medium in the sheet separation nip region. The sheet separating feeder separates and feeds the recording medium contacting the sheet feeding body. The image forming part forms an image on the recording medium. The bend applier having a leading end of an elastic material contacts and bends the recording medium before the sheet separation nip region and generates a wrinkle extending on the recording medium in a sheet conveying direction.

A sheet feeding device includes a pickup roller, a feed roller, a retard roller, a conveyance rollers pair. The pickup roller contacts a sheet at a first contact point in a pickup position and rotates to convey the sheet in a predetermined conveyance direction. The feed roller is disposed on a downstream side of the pickup roller in the conveyance direction. The retard roller contacts the feed roller at a second contact point and conveys the sheet while separating the sheet. The conveyance rollers pair contacts each other at a third contact point and conveys the sheet passing through the second contact point to a conveyance path. The first contact point, the second contact point and the third contact point are disposed on a linear line in the conveyance direction, when viewed from axial directions of the rollers.

A medium feeding apparatus includes a medium supporting portion supporting a medium, a feeding roller that feeds the medium, a separation portion configured to advance and retreat with respect to the feeding roller, a path forming member that is a member positioned upstream in a medium feeding direction with respect to a contact position between the feeding roller and the separation portion, that is configured to advance and retreat with respect to the feeding roller, and that is configured to narrow a medium feeding path directed toward the contact position, and a first pressing portion pressing the path forming member toward the feeding roller, in which the path forming member displaces the separation portion in a direction away from the feeding roller when the path forming member is pushed down in a direction retreating from the feeding roller by a medium having a thickness exceeding a predetermined thickness.

A sheet feeding device includes a stacking member, a feeding unit, and a detachable separation unit. The feeding unit feeds sheets stacked from the stacking member. The separation unit separates the fed sheets one by one. The separation unit includes a rotating member to abut and separate from the feeding unit and to rotate, a biasing member to bias the rotating member toward the feeding unit, and an engaged member to be engaged with an engagement member included in the sheet feeding device. The engagement member can move to a first position where the engagement member is engaged with the engaged member, and a second position away from the engaged member. Where the engagement member moves from the first to the second position when the separation unit is attached to the sheet feeding device, the separation unit moves in a detachment direction using the biasing member.

A sheet feeding device includes a sheet feeding roller, a following roller, a rotational speed detection part, and a control part. The rotational speed detection part is configured to detect a rotational speed of the following roller. The control part is configured to accelerate a rotation of the sheet feeding roller and to adjust a sheet interval. The control part obtains a rotational rate of the following roller to the sheet feeding roller based on the rotational speed of the following roller, obtains an actual linear velocity of the sheet based on the rotational rate of the following roller and a theoretical linear velocity of the sheet after accelerating the rotation of the sheet feeding roller, and then adjusts the sheet interval based on the actual linear velocity of the sheet.

A sheet feeding device includes: an accommodating unit having a placement surface on which the stack of sheets is mounted; an inclined member having an inclined surface inclined relative to the placement surface to extend in an inclined direction and a back surface opposite the inclined surface; a sheet pick-up unit for feeding an uppermost sheet in the stack of sheets toward the inclined member; and a sheet separating member provided on the inclined surface. The sheet separating member includes a plurality of separation pieces and a support portion those made of resin. The support portion supports the separation pieces at positions closer to the back surface than to the inclined surface so that the separation pieces are movable away from the placement surface in the inclined direction and toward the back surface in a normal direction of the inclined surface independently from one another.

A holder supports a separation member. When a sheet cassette is attached to a main body portion, as the sheet cassette is moved in its attachment direction, a moving mechanism causes the holder to move from an initial position to an operation position. When the holder is at the initial position, the separation member is spaced from a feeding member and is able to pass below the feed-out member. When at the operation position, the holder presses the separation member against the feeding member. When the sheet cassette is attached to the main body portion, the moving mechanism causes the holder to move to the operation position after the separation member passes below the feed-out member. When the sheet cassette is drawn from the main body portion, the moving mechanism causes the holder to move to the initial position before the separation member reaches below the feed-out member.