TAPE CARTRIDGE HAVING A SHUTTER WITH SELF-LOCKING FUNCTION

1522046 Tape-cartridges; sliding lids for boxes INTERNATIONAL BUSINESS MACHINES CORP 17 Aug 1976 [29 Aug 1975] 34139/76 Headings B8M and B8P A tape-cartridge or container comprises a shutter slidable between closed and open positions to cover or expose one or more apertures, e.g. access holes for co-operatively associated apparatus, in the peripheral wall. The shutter has an external detent by which it is movable and interengageable formations on the wall and detent secure the shutter in closed position where it is releasable by a separate device or tool. In the cartridge shown, a thin resilient shutter 44, extending in both directions from a resilient bifurcated detent member 45 is moved thereby to slide in external walls 13 and 15 to cover and expose access apertures 17 and 18, detent heels 49 projecting outwardly into, and locking with, recesses 125 in side edges of an opening 50 and into recesses 126 at closed and open positions of the shutter. When the (closed) cartridge is required to be operated, e.g. with a player, it is inserted into a fixed housing 110, Fig. 7, and located therein by a resiliently mounted member 112. As insertion is effected a resiliently mounted pawl 122 rides over detent 45 and engages its rear wall and a stationary pawl 124 attached to the inside of the wall 114 of the housing 110 catches the detent so that a V-notch 123 flexes the tips 119 inwardly to free heels 49 from recesses 125 and slide the shutter into open position and allow a transducer head 131 and capstan 91 to pass through apertures 17 and 18. When the cartridge is withdrawn from housing 110, the shutter is moved automatically into closed position by the engagement of detent 45 between the tip of pawl 122 and the rear wall. In another embodiment, Fig. 13 (not shown) locking heels on the detent engage shoulders projecting from the edge detent engage shoulders projecting from the edges of opening 50.