Provided is a drive transmission switching mechanism that can switch and drive two circulation units by one motor in response to a switching operation of a paper sheet transport direction. A paper sheet storage unit includes a first circulation unit 100 and a second circulation unit 200 that respectively receive transported paper sheets upon reception of a drive force from a single motor 302 and feed paper sheets stored therein, a sorter 310 that sorts paper sheets to either one of the circulation units, and a drive transmission switching mechanism 400 that transmits a drive force from the motor to either one of the circulation units. The drive transmission switching mechanism is activated in conjunction with an operation to change the posture of the sorter, thereby switching and transmitting the drive force to either one of the circulation units.

A sheet supplying apparatus includes an alignment member pivotable to an alignment location for blocking and aligning fore-ends of media contained on a loading table, and a transport-allowing location for allowing a medium picked up by a pickup member to be transported, a cam gear including a gear portion partially including a tooth-omitted portion, and a cam portion for switching the alignment member between the alignment location and the transport-allowing location at first and second rotating locations, a swing arm pivotable about a same axis as a rotation axis of a main gear, and first and second swing gears supported by the swing arm to interlock with the main gear, selectively interlocking with the gear portion according to a rotating direction of the main gear, and rotating the cam gear to the first and second rotating locations.

A feeding apparatus includes a knock-up plate to be rotatably installed on a main body of an image forming apparatus and install a paper, a knock-up spring to elastically apply pressure to the knock-up plate in a direction of a pickup roller, a cam to be fixed at one end of a knock-up shaft and downwardly apply pressure to the knock-up plate, and a driving force transfer member to transfer a rotating force of the knock-up shaft to the pickup roller.

A drive transmitting device includes a first gear; a second gear in engagement with the first gear; wherein a first tooth which is at least one of teeth of the first gear has a tooth surface contacting a tooth of the second gear, wherein the tooth surface has such a shape that a contact point of the first tooth of the first gear to the tooth of the second gear is in a region of a first gear side with respect to a line of action which is formed by movement of a contact point between a tooth of the second gear and a second tooth of the first gear immediately before the first tooth with respect to a rotational moving direction of the first gear.

A drive transmission device includes a first gear, a second gear, a switch arm, a third gear, a first sector gear including a first teeth portion and rotatable about a second axis in a predetermined direction, a second sector gear including a second teeth portion and engaging the first sector gear movably with play in the predetermined direction, a lever, a solenoid, and a first urging member. The switch arm has a cam contact surface, and the second sector gear includes a cam configured to contact the cam contact surface. When the first sector gear rotates in the predetermined direction for a predetermined amount from a state where the third gear engages the first gear and where the first teeth portion and the second teeth portion disengage from the second gear, the first teeth portion engages the second gear, and the second teeth portion disengages from the second gear.

Provided is a cap unit that can prevent or suppress collision between the drive gear and intermittent gear when the drive gear and intermittent gear begin to mesh. A cap unit 25 has a moving mechanism 28 that moves a cap 26. The moving mechanism 28 has an intermittent cam gear 36 with a cam channel 43; a drive gear 35; and a cap holder 45. The cap holder 45 includes a holding member 48 that holds the cap 26; a cam follower pin 49; a pin support mechanism 50 that supports the cam follower pin 49; and a coil spring 51 that urges the cam follower pin 49 toward the bottom 43a of the cam channel 43. A slope 57 is disposed to the bottom 43a of the cam channel 43. The cam follower pin 49 is on the slope 57 when meshing of the intermittent cam gear 36 and drive gear 35 is disengaged, and the intermittent cam gear 36 turns in conjunction with the cam follower pin 49 moving on the slope 57 due to the urging force of the coil spring 51.

A sheet feeder includes a sheet platen, a pickup roller, a feeding roller, a regulating portion, a driving mechanism, a feeding control unit, a sheet sensor, and a determination processing unit. The feeding control unit executes a feeding operation by rotationally driving the pickup roller and the feeding roller in a state where the regulating portion is located at a retreating position. The sheet sensor is located at a downstream side in the feeding direction of the feeding roller. The determination processing unit determines whether the sheet feeding has succeeded or not based on a signal from the sheet sensor. After a start of the feeding operation, when the determination processing unit determines that the sheet feeding has failed, the feeding control unit once moves the regulating portion located at the retreating position to the abutting position and then executes the feeding operation again.

A driving force transmission device includes a drive gear, a driven gear, which includes a gear portion and a partially toothless gear portion, rotates by the gear portion meshing with the drive gear, stops rotating in response to the partially toothless gear portion facing the drive gear, a first cam member and a second cam member which operate in conjunction with the driven gear, a first elastic member for urging the first cam member, a follower member to which urging force is applied by a second elastic member and which is moved by the second cam member, and a contact portion for coming into contact with the first cam member by urging force of the first elastic member. The first cam member includes a home cam surface for coming into contact with the contact portion so that rotation of the driven gear is limited.

A drive transmission device includes a rotatable driving member; a rotatable follower member, and an elastic member. The drive transmission device includes a first rotatable member and a second rotatable member. The first rotatable member includes first and second driving portions and a limiting portion. The second rotatable member includes a first driven portion, a second driven portion and a contact portion contacting the limiting portion. The second driving portion is adjacent to the limiting portion with respect to a rotational axis direction of the first rotatable member. The second driven portion is adjacent to the contact portion with respect to a rotational direction of the second rotatable member.

A sheet feeding apparatus, including: a stacking unit; a feed unit having a contact portion to be brought into contact with a sheet stacked on the stacking unit and a noncontact portion kept out of contact with the sheet, the feed unit being configured to feed the sheet in a contact state in which the contact portion is in contact with the sheet, and then turn into a noncontact state in which the noncontact portion faces the sheet so as to be kept out of contact with the sheet; a conveyance unit arranged downstream of the feed unit; and a drive unit configured to drive the conveyance unit at a first speed in the contact state and to drive the conveyance unit at a second speed higher than the first speed in the noncontact state.