US 5,206,676 A · Photographic film cassette

Abstract

In a photographic film cassette, light trapping fabric is provided on each of two inside surfaces of a film passage mouth which define a film passageway. Inner recesses, retracted from the inside surfaces, have the inner edges of the light trapping fabric attached thereto, with an adhesive agent enclosing the inner edges. In a preferred embodiment, tiny grooves are formed in the recesses to provide an increased attaching force, so that a considerable degree of attachment can be maintained. Further, the cassette has two shell halves which are joined together at respective edges. A projection is formed at a first one of those edges. The second edge has a contact projection thereon, for fitting in an inside recess of the first edge. Also, a crooked portion is formed along the juncture of the respective edges. As a result, no light will come through the spacing beside the film. A film leader is advanced through the film passageway by rotating the spool to an outside of the film passage mouth. When the film leader is forced to advance, it will never peel off the light trapping fabric, and so can be advanced reliably without being stopped by the light trapping fabric.

Claims17

Dependent claims

A photographic film cassette having a spool with photographic film wound thereon and a cassette shell for containing the film in a light-tight fashion and for supporting the spool rotatably, a film passageway being formed on said cassette shell for directing the film to a film passage mouth of said cassette, means for advancing a film leader of said film through said film passageway by rotating said spool toward an outside of said film passage mouth, and two light trapping members provided respectively on upper and lower inside surfaces of said film passageway for trapping light;

said cassette comprising:
two inner recess portions, associated with said upper and lower inside surfaces, for increasing a degree of retraction from said upper and lower inside surfaces in an inward direction toward an inside of said cassette shell, inner edges of said two light trapping members being attached to respective ones of said two inner recess portions so as to increase an interval between upper and lower inside surfaces of said two light trapping members in the inward direction on said inner edges, so that a leading end of said film leader is surely advanced into a path between said two light trapping members toward the outside of said film passage mouth;
further comprising an adhesive agent for completely enclosing said inner edges of said two light trapping members, thereby to attach said two light trapping members to respective ones of said two inner recess portions.

Dependencies are inferred from the claim text.

Photographic film cassette

Life of this patent

Photographic film cassette

Life of this patent

Abstract

Claims17