Film cassette with spool core having fastening hook

摘要

In a film cassette, a spool core about which a filmstrip is coiled is rotated in an unwinding direction to thrust a leading end portion of the filmstrip from inside to outside the cassette. The filmstrip has a trailing or inner end portion with a hole in it. The spool core includes a double-hook piece in the hole having a shorter hook and a longer hook. The shorter hook projects from the hole in the unwinding direction to slightly overlie the trailing end portion to engage the trailing end portion for pushing the filmstrip off the spool core to thrust the leading end portion outside the cassette when the spool core is rotated in the unwinding direction, but which will exit the hole as the trailing end portion begins to separate from the spool core. The longer hook projects from the hole in a winding direction to substantially overlie the trailing end portion to engage the trailing end portion for preventing the trailing end portion from completely separating from the spool core when the shorter hook is removed from the hole, but which can be backed out of the hole by rotating the spool core relative to the trailing end portion in the unwinding direction.