Mechanism for opening and closing the shutter of a disc cassette

A shutter opening and closing mechanism in a recording and reproduction apparatus which uses a cassette, the cassette having a freely openable and closable shutter and locking means for locking the shutter in a closed state, comprising:

• lock releasing means for releasing the locking means of the shutter;
• shutter opening means for opening the shutter when its locking means is released by said lock releasing means;
• and
• shutter closing means having a torsion section that creates a twisting force in a plane substantially parallel to a direction of movement of the cassette relative to the shutter opening and closing mechanism for engaging with an engaging part of the shutter and closing the same,
• wherein said shutter closing means is resiliently biased toward the cassette and has a first force acting on the locking means which is smaller than a releasing force required to release said locking means, and a second force acting on the engaging part of the shutter such that the shutter will not be disengaged from said engaging part when the shutter is being closed.