TAPE CASSETTE

摘要

An improved, Philips-type tape cassette having a shiftable tab for selectively blocking the opening formed by the removal of the conventional knock-out tab used to provide a means for determining the presence of pre-recorded material on the tape carried by the cassette. The two shells of the cassette have improved tongue and groove structure at the adjacent sides and ends to fit the shells together and to prevent relative movement therebetween. Relatively wide front and rear end walls on one of the shells provide a pair of beams of increased thickness to prevent bending of the cassette so as to maintain its structural integrity. An improved internal lock is provided near the central part of the rear wall where an attachment screw would be impractical. Each hub of the cassette has an improved leader-holding insert which is received within an outer peripheral recess and supports the tape across the recess to avoid "spoking" in the tape pack formed on the hub. Each of a pair of improved idler posts integral with one of the shells provides a pair of spaced, cylindrical bearing surfaces while providing a space for receiving lubricant. Tape guides near the open, tape-exposing extremity of the cassette are perpendicular to the inner surface of each shell to minimize the "barber pole" effect on the tape.