Film cassette

Claim 1

IN AN APPARATUS OF THE TYPE DESCRIBED, THE COMBINATION OF A CAMERA HAVING A CASSETTE-RECEIVING CHAMBER; A FILM CASSETTE INSERTABLE INTO SAID CHAMBER IN FIRST AND SECOND POSITIONS AND COMPRISED OF TWO HINGED MEMBERS MOVABLE BETWEEN OPEN AND CLOSED POSITIONS; SPACED RECESSES IN THE OUTER WALL OF SAID CASSETTE; PROTRUSIONS IN SAID CAMERA CHAMBER COOPERATING WITH SAID RECESSES WHEN SAID CASSETTE IS INSERTED INTO SAID CAMERA; A BLOCKING MEMBER MOUNTED ON SAID CASSETTE AND MOVABLE BETWEEN A NOR MALLY OPERATIVE POSITION WITH RESPECT TO AT LEAST ONE OF SAID RECESSES IN WHICH IT PREVENTS INSERTION OF SAID CASSETTE INTO SAID CAMERA CHAMBER IN SAID SECOND POSITION, AND AN OPERATIVE POSITION WITH RESPECT TO SAID RECESSES IN WHICH IT ALLOWS INSERTION OF SAID CASSETTE INTO SAID CHAMBER IN SAID SECOND POSITION, SAID BLOCKING MEMBER BEING MOVED TO SAID INOPERATIVE POSITION IN RESPONSE TO THE INSERTION OF SAID CASSETTE INTO SAID CHAMBER IN SAID FIRST POSITION; HOLDING MEANS FOR MAINTAINING SAID BLOCKING MEMBER IN THE POSITION TO WHICH IT HAS BEEN MOVED; AND RESTORATION MEANS FOR MOVING SAID BLOCKING MEMBER TO SAID NORMALLY OPERATIVE POSITION WHEN SAID CASING MEMBERS ARE OPENED TO PROVIDE ACCESS TO THE INTERIOR OF SAID CASSETTE.