Patent ID: 8596636

Claim:
An image forming apparatus comprising: a sheet feeding unit configured to separate stacked sheets one at a time and to convey and feed the separated sheets, the sheet feeding unit comprising: a holding section configured to hold sheets; a separation pad configured to contact a sheet sent from the holding section and impart a predetermined conveyance resistance to the sheet; a separation roller that rotates while pressing the sheet against the separation pad and imparts a conveyance force to the sheet; a drive source configured to supply driving force to the separation roller; a conveyance roller that is disposed at a position downstream of the separation roller in a conveyance direction, wherein the conveyance roller rotates at a circumferential speed greater than a circumferential speed of the separation roller, to thus impart conveyance force to the sheet, and wherein the conveyance roller and the separation roller are disposed so as to simultaneously contact the same sheet; and a drive shutoff unit configured to shut off the driving force supplied to the separation roller when the conveyance roller imparts the conveyance force to the sheet, such that the separation roller rotates in a following manner with conveyance of the sheet; and an image forming section configured to produce images on the sheet conveyed from the sheet feeding unit, and a sheet entrance of the image forming section being provided with a registration roller disposed immediately before the image forming section in the conveyance direction and configured to correct a skew of the sheet fed from the sheet feeding unit, wherein a distance between the separation roller and the conveyance roller is smaller than a distance between the conveyance roller and the registration roller, and wherein a circumferential speed of the registration roller is smaller than the circumferential speed of the conveyance roller and larger than the circumferential speed of the separation roller.