A sheet feeding apparatus includes a disengagement mechanism to disengage a rotary feeding member and a separation member to be apart from each other, a pressing portion to press an upper face of a sheet supported on a sheet supporting portion, and a detector to detect displacement of the sheet pressed by the pressing portion. A controller executes one mode among a plurality of modes to feed the sheet supported on the sheet supporting portion based on a detection result of the detector. In a first feed mode, a leading edge of the sheet passes a position of a separation portion with the rotary feeding member and the separation member disengaged by the disengagement mechanism. In a second feed mode, the leading edge of the sheet passes the separation portion with the rotary feeding member and the separation member engaged.

A medium feeding apparatus includes a feed roller that feeds media. A separation roller nips the media together with the feed roller to separate it and is rotated in a first direction to feed the media. A motor applies driving torque to the separation roller in a second direction opposite to the first direction. A torque limiter, when rotation torque applied to the separation roller in the first direction exceeds a preset upper torque limit, causes the separation roller to rotate at idle in the first direction independently of the driving torque. During feeding operations, including feeding of first and second media, a controller that controls the motor provides a break period in which the motor is not driven. The break period contains the timing when a rear edge of the first medium leaves a nip position between the feeding and separation rollers.

There is provided a roller including: a shaft, and an elastic body portion that is provided on an outer peripheral surface of the shaft, in which the elastic body portion includes a plurality of first recessed portions which are provided on one side of the roller in a shaft mounting direction at intervals in a circumferential direction of the roller and each have a bottom portion, and a plurality of second recessed portions which are provided on the other side of the roller in the shaft mounting direction at intervals in the circumferential direction of the roller and each have a bottom portion, and in which each of the first recessed portions is positioned between the adjacent second recessed portions in the circumferential direction of the roller in the side view of the roller in the shaft mounting direction.

A sheet feeder includes: a casing; a first roller; a pressing portion; a first spring; and a second spring. The pressing portion is movable between a first position and a second position via a third position. The pressing portion in the first position faces the first roller within a conveying region defined in the casing. The pressing portion in the second position is separated from the first roller farther than in the first position. The third position is located between the first position and the second position. The first roller is exposed to the conveying region. The first spring urges the pressing portion toward the first roller when the pressing portion is disposed between the first position and the second position. The second spring urges the pressing portion toward the first roller when the pressing portion is disposed between the second position and the third position.

Provided are a rubber composition capable of imparting a high tensile strength to a roller main body so as to be able to be used for equipment that allows paper to pass through at high speed, while maintaining high abrasion resistance of the roller main body and a favorable paper feeding performance of the paper feeding roller; and a paper feeding roller. There is provided a rubber composition contains: a rubber that includes a non-oil extended EPDM having an ethylene content of 55 to 72%; and more than 20 parts by mass and 30 parts by mass or less of a filler, and 2.5 parts by mass or more of a peroxide crosslinking agent per 100 parts by mass of the rubber, in which the filler contains 15 to 30 parts by mass of an amorphous silica per 100 parts by mass of the rubber.

A medium conveyance device includes a guiding member that is movably supported on a frame, a pick roller that is rotatably supported on the guiding member and that rotates to feed a medium that is placed on a tray to a feed roller, and a joint unit that transmits a rotation force from a drive shaft to the pick roller.

A medium feeding device is provided with a feeding section for feeding a medium and sensors for detecting the medium. The feeding section includes a feed roller and a separation roller, the sensors form a sensor line in which the plurality of sensors is aligned in a feeding direction of the medium to be fed, the two sensor lines are arranged in such a manner that the sensors overlap with each other in a width direction of the medium to be fed, and the sensor lines are so configured as to extend, in the feeding direction, from an upstream region upstream of a nip point where the feed roller and the separation roller make contact with each other, a nip region including the nip point, and to a downstream region downstream of the nip point.

A paper sheet feeding unit includes: a plurality of feed rollers; a plurality of gate rollers respectively disposed opposite to the plurality of feed rollers in a one-to-one relationship; a biasing member that biases the plurality of gate rollers individually in a direction of the plurality of feed rollers; and a supporting member that supports the plurality of gate rollers and the biasing member.

An image reading apparatus includes a feed roller configured to feed paper toward a reading section, and a medium detection section provided along a transport path between the feed roller and the reading section and configured to include a transmitting portion configured to output an output value equivalent to a magnitude of an ultrasonic wave, and determines whether the transport of the paper is to be continued or to be brought to a halt on the basis of a lower limit value and an upper limit value for the output value, which are set in accordance with the kind of the paper. Further, in a case where the output value satisfies a first condition, a transport of the medium is continued, and in a case where the output value satisfies a condition different from the first condition, the transport of the medium is brought to a halt.

A medium feeder includes a feed roller that feeds a medium loaded on a medium loading section; a transport roller disposed downstream relative to the feed roller; a first driving source that drives at least the feed roller; a second driving source that drives at least the transport roller; and a housing that houses the feed roller, the transport roller, the first driving source, and the second driving source, wherein the housing includes a lower unit that constitutes a lower part of the housing, and an upper unit openable relative to the lower unit, and the first driving source and the second driving source are disposed on both sides relative to a center part of the lower unit in a width direction perpendicular to a medium transportation direction.