A feed roller assembly including an axle, a feed roller fixedly mounted around the axle and turned with it to feed a sheet of paper forward, an end cap fixedly mounted on one end of the axle and having a projecting rod raised from an inner side, the projecting rod having a bevel face, and a transmission gear turned about one end of the axle adjacent to the end cap, the transmission gear having a springy projecting rod raised from one end and moved to act against the projecting rod of the end cap, causing the end cap and the axle to be turned with the transmission gear, the springy projecting rod of the transmission gear passing over the bevel face of the projecting rod of the end cap when the roller is pulled by a transmission roller, which delivers the fed sheet of paper forwards, to turn the axle and the end cap at a higher speed than the transmission gear, permitting the end cap and the axle to be turned relative to the transmission gear.