Sheet feeding apparatus, image reading apparatus and image forming apparatus

1. Field of the Invention A sheet feeding apparatus having a stocking plate on which a plurality of sheets are stackable, a separating device for separating the sheets stacked on the stocking plate one by one by a pair of pressure contact members, a feeding device for feeding the sheets, and a pressure releasing device for releasing the pressure contact of the pair of pressure contact members has a returning device for acting on the pressure releasing device to thereby return the pair of pressure contact members to their pressure contact state after a single-sheet feeding is terminated when the sheets are fed with the pair of pressure contact members pressure-released by the pressure releasing device.