A separation roller for a sheet feeding apparatus includes an outer circumferential portion formed from an elastic material, a core portion to which the outer circumferential portion is attached; and a flange portion including a plurality of projecting portions each projecting to an outside in a radial direction with respect to the core portion. At least one of the plurality of projecting portions includes a first surface provided on a side portion thereof on an upstream side in a first direction in which the separation roller rotates in such a manner as to follow the rotary feeding member rotating to feed the sheet. The first surface extends more upstream in the first direction at a position further on an outside in a radial direction with respect to a rotation axis of the separation roller as viewed in the axial direction.

A sheet feeding device includes a sheet accommodating portion mounted in a main assembly. With respect to a crossing direction perpendicularly crossing a pulling-out direction of the sheet accommodating portion from the main assembly as viewed in a direction of gravitation, the main assembly is provided with a positioning portion. A member-to-be-engaged is provided in one of the main assembly and the sheet accommodating portion. An engaging member is provided in the other of the main assembly and the sheet accommodating portion. The engaging member is elastically deformed when the sheet accommodating portion is pulled out in the pulling-out direction from a mounting position. The engaging member is provided swingably in the other one of the main assembly and the sheet accommodating portion so as to be capable of changing a position thereof with respect to the crossing direction.

A feeding unit includes: a retard roller; a holder section; a protruding section; an accommodating section; a pressing section; a first restricting section; and a second restricting section. The holder section rotatably holds the retard roller. The protruding section serves as a rocking fulcrum of the holder section. The accommodating section accommodates the holder section. The pressing section presses the holder section. The first restricting section restricts movement of the holder section in a retreating direction. The second restricting section restricts movement of the holder section in a direction opposite to the retreating direction. The pressing section is arranged so as to deviate in a Y direction with respect to a virtual line passing through a middle point of the protruding section and a middle point of the first restricting section. The holder section comes into contact with the first restricting section and the second restricting section.

A paper pickup mechanism includes a mechanical frame, a pickup roller module, a feeding roller module, a driving device, a separation roller module and an energy storage element. The mechanical frame has a platform. The pickup roller module is pivoted to and connected to the mechanical frame. The feeding roller module is pivoted to and connected to the mechanical frame. The driving device is mounted to the mechanical frame. The separation roller module is pivoted to and connected to the mechanical frame. The energy storage element is mounted between the mechanical frame and the separation roller module. When the separation roller module rotates together with the feeding roller module in a forward direction, the energy storage element accumulates energies. When more than one piece of paper is fed into the paper pickup mechanism, the energy storage element releases the energies.

A sheet feeder includes a roller, a reflector, a sensor, and a rotating speed detector. The reflector is integrally attached to the roller, the reflector including first reflecting surfaces and second reflecting surfaces arranged alternately along a circumference direction of the roller. The sensor includes a light emitter and a light receiver. The rotating speed detector is configured to detect a rotating speed of the roller based on a result of the detection by the sensor. Each of the first reflecting surfaces reflects the inspection light at a first reflection ratio, and provides a first reflection light path along which the inspection light is directed to the light receiver. Each of the second reflecting surfaces reflects the inspection light at a second reflection ratio smaller than the first reflection ratio, and provides a second reflection light path along which the inspection light is directed outside the light receiver.

A sheet processing apparatus is described. The sheet processing apparatus includes a housing section, a conveyance mechanism and a controller. The housing section accommodates a sheet. The conveyance mechanism conveys the sheet accommodated in the housing section to a predetermined position at the downstream side in a sheet conveyance direction. The controller controls the conveyance mechanism to remove a needle-free binding section of a sheet bundle if a conveyance jam of the sheet occurs.

A sheet feeding device includes a sheet stacking unit to stack a plurality of sheets, a feeding unit to feed sheets stacked on the sheet stacking unit, a separation unit, and a moving unit provided with at least a first moving member and a second moving member. The separation unit contacts the sheets fed by the feeding unit and separates a sheet from the sheets. The moving unit contacts the first and the second moving members to move a sheet contacting the first and the second moving members to an upstream side in a feeding direction. A leading edge of the sheet is positioned between the separation unit and the feeding unit. When pressed by the sheet, the first and the second moving members are configured to thrust-move independently of each other.

A sheet supplier, including: a tray including a sheet support surface; a sheet supply roller configured to supply an uppermost one of sheets; a rotational member configured to contact a lowermost one of the sheets; a presser configured to press the supply roller relative to the rotational member; and a supporter configured to support the rotational member by a contact portion such that the rotational member is rotated by a movement of the lowermost sheet and to limit a movement of the rotational member caused by a force of the lowermost sheet in a sheet supply direction; wherein, where static friction coefficients between the supply roller and the uppermost sheet, between the sheets on the support surface, between the rotational member and the lowermost sheet, and between the rotational member and the contact portion are respectively defined as 2, 3, and 4, the following expressions are satisfied: 1>4>2, 3>4.

A paper feeder includes a lift plate, a pickup roller, a feed roller, a retard roller, a rotation-count detection sensor, and a control unit. The rotation-count detection sensor outputs a rotation-count detection signal. The rotation-count detection signal indicates a rotation count of the retard roller. The control unit detects the rotation count of the retard roller based on the rotation-count detection signal. The lift plate separates from the pickup roller before the control unit detects the rotation count of the retard roller. The feed roller is driven when the control unit detects the rotation count of the retard roller. The retard roller is in abutting contact with the feed roller when the control unit detects the rotation count of the retard roller. The control unit determines whether replacement of the retard roller is necessary or not, based on the detected rotation count of the retard roller.

A feeding apparatus includes a feeding member to feed a recording material stacked on a stacking portion, a first conveyance member, a separation member to form a nip portion with the first conveyance member and separate a plurality of recording materials at the nip portion, a second conveyance member, a detection unit, and a control unit. The control unit controls to feed a stacked first recording material and, after a first recording material rear end passes through the feeding member, the control unit controls to feed a stacked second recording material while partially overlapped with the first recording material and thereby the first recording material rear end passes through the nip portion after a second recording material leading end passes through the nip portion. The control unit controls so that the second recording material is stopped before the second recording material leading end reaches the second conveyance member.