Patent ID: 8876034

Claim:
A sheet storage cassette which contains a print sheet in roll form wound into a hollow cylindrical shape and is attached to a printing apparatus, the cassette comprising: a sheet retaining shaft which retains the print sheet in roll form by being made to extend through a hollow portion of the print sheet and making an urging member urge an inner surface of the hollow portion in a diameter expanding direction; and a support portion which rotatably supports said sheet retaining shaft, wherein the urging member protrudes from a maximum outer diameter of said sheet retaining shaft while the print sheet is not attached to said sheet retaining shaft, and urges the inner surface of the hollow portion of the print sheet in the diameter expanding direction while the print sheet is attached to said sheet retaining shaft, and a rib portion which is provided at said sheet retaining shaft and continuously extends in a rotational direction and contacts a pickup guide, which picks up a leading end of a print sheet which is rotated by a roller portion of said printing apparatus, when the urging member rotates, wherein the rib portion is provided to prevent the pickup guide from interfering with the urging member which rotates together with said sheet retaining shaft.