US 11,702,305 B2
Sheet feeding device and image forming apparatus
Kenji Kuroda, Osaka (JP); Hironori Ogasawara, Osaka (JP); Yasumasa Morimoto, Osaka (JP); and Toshiki Fukunishi, Osaka (JP)
Assigned to SHARP KABUSHIKI KAISHA, Sakai (JP)
Filed by SHARP KABUSHIKI KAISHA, Sakai (JP)
Filed on Dec. 29, 2020, as Appl. No. 17/136,459.
Claims priority of application No. 2020-008516 (JP), filed on Jan. 22, 2020.
Prior Publication US 2021/0221633 A1, Jul. 22, 2021
Int. Cl. B65H 3/06 (2006.01)
CPC B65H 3/0684 (2013.01) [B65H 3/0669 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A sheet feeding device comprising:
a pickup roller that picks up a sheet loaded on a sheet loading tray;
a lifting/lowering mechanism that lifts and lowers the pickup roller; and
a driver motor that drives the lifting/lowering mechanism, wherein the pickup roller is lowered from a lifted position to pick up the sheet on the sheet loading tray, wherein
the lifting/lowering mechanism includes a holding mechanism that releasably restricts the pickup roller from being lowered from the lifted position,
the driver motor drives the lifting/lowering mechanism so that the pickup roller is lowered from the lifted position, and a drive suspend operation is performed in which driving of the lifting/lowering mechanism by the driver motor is suspended after a predetermined time period, wherein during the drive suspend operation, the pickup roller does not contact the sheet loading tray or the sheet on the sheet loading tray, and the predetermined time period begins from a time point when the pickup roller is released from being restricted by the holding mechanism at the lifted position,
the lifting/lowering mechanism includes:
a drive rotation shaft rotatably supported by a sheet feeding device main body around a rotation axis, the drive rotation shaft being rotationally driven by the driver motor;
a holding member swingably supported by the drive rotation shaft via a torque limiter, the holding member rotatably holding a rotation shaft of the pickup roller around the rotation axis; and
a drive transmission mechanism that transmits a rotational driving force from the drive rotation shaft to the pickup roller, wherein:
the pickup roller is lifted and lowered as the driver motor rotates the drive rotation shaft,
the holding mechanism includes a first pivoting member provided on the drive rotation shaft and a second pivoting member provided in a member on a side of the sheet feeding device main body such that the second pivoting member rotates around a pivoting axis along the drive rotation shaft,
the first pivoting member is provided with a first engagement, the second pivoting member is provided with a second engagement and a locking device when the second engagement engages with the first engagement, the first pivoting member is pivoted with the drive rotation shaft so that the locking device locks the pickup roller in the lifted position,
the holding member rotatably couples the rotation shaft of the pickup roller and the drive rotation shaft, and
the drive transmission mechanism includes a driving member provided on the drive rotation shaft, a driven member provided on the rotation shaft of the pickup roller, and a drive transmission member that transmits the rotational driving force from the driving member to the driven member.