Patent ID: 7549630

Claim:
A sheet supplying device comprising: a base; a tray on which a stack of sheets can be placed, the tray being able to be raised and lowered with respect to the base; a feed roller provided rotatably at the base and positioned above the tray, and when the feed roller rotates while frictionally engaging with a topmost sheet of the stack of sheets, the feed roller can convey the sheet; a driving mechanism able to drive the feed roller to rotate; an urging member urging the tray toward the feed roller; a first eccentric cam rotatably provided at the base, and including a large-radius outer peripheral portion having a radius, and a small-radius outer peripheral portion having a smaller radius than the radius of the large radius outer peripheral portion, the first eccentric cam rotating directly interlockingly with rotation of the feed roller; and a second eccentric cam rotatably pivotally connected to the tray, and including a large-radius outer peripheral portion having a radius, and a small-radius outer peripheral portion having a smaller radius than the radius of the large radius outer peripheral portion, the second eccentric cam being located below the first eccentric cam and being able to engage with the first eccentric cam, wherein the respective small-radius outer peripheral portions of the first eccentric cam and the second eccentric cam are capable of abutting one another during operation of the device, resulting in the tray being pushed upward by the urging member and approaching the feed roller so as to be able to convey the sheet, and the respective large-radius outer peripheral portions of the first eccentric cam and the second eccentric cam are capable of abutting one another during operation of the device, resulting in the tray being pressed by the large-radius outer peripheral portion of the first eccentric cam and moving away from the feed roller so as to be unable to convey the sheet.