Patent GB-1160801-A (GB)
Title: Tape Playback Apparatus
IPC: G11B23/06
Filed: 1967-01-16
Abstract: 1,160,801. Magnetic tape cartridges and players; track selecting. TENNA CORP. 16 Jan., 1967 [29 June, 1966], No. 2302/67. Heading G5R. A tape player comprises multiposition means for conditioning the player to play back either one of two different types of magnetic tape cartridge, means for positioning either type of cartridge in a play-back position on the player, means for sensing the type of the cartridge in the play-back position, and means for selectively operating the multiposition means to play back the cartridge which is then in the play-back position. Pinch-roller selection.-A cartridge (e.g. Fig. 2) is inserted at A, Fig. 1, i.e. above a dividing plate 32, Fig. 4. Where, as here, an opening 40 is provided in the base of the cartridge, a sensing finger 92, Fig. 4, rises into it. As movement continues, the cartridge pushes over a pivoted arm 94<SP>1</SP>, Fig. 4; movement of arm 941 by this cartridge brings about withdrawal of a tab 80, Fig. 5, from between collars 77, 78 on a sleeve 71 slidable but not rotatable on a shaft 68, Figs. 4 and 5. Such withdrawal permits a spring 79, Fig.5, to move sleeve 71 into contact with a second sleeve 72, the contacting ends forming the members of a dog clutch. Pinch roller action.-With further movement of the cartridge, the cartridge front makes contact with an arm 81 projecting from sleeve 72, thereby initiating rotation of sleeve 72 and with it sleeve 71 and hence shaft 68. Then a toggle spring 70, linked at 69 to the shaft, flips the shaft to a position where a pinch roller 41, Figs. 4 and 5, has entered opening 40, has released a brake 42, Fig. 2, to allow a spool 43 to unwind tape 52, and now presses tape 52, Fig. 2, against a capstan 35, Figs. 1 and 4. Tape positioning.-As shaft 68 rotates to the " pinch roller upright " position, a rod 166 provided on the shaft raises the free end of a strip spring 165, Fig. 4, secured at one end to the underside of plate 32. This spring in turn raises, by a fraction of an inch, a tape guide 160, Fig. 4, having a U-shaped cut-out for engaging the tape. Alternative cartridge.-A cartridge, Fig. 3 (not shown), having no opening in its base and provided with a spring-biased felt pad which pushes the tape against the capstan when the cartridge is in playing position, may be used. In this case the pinch roller 41 is not needed. Accordingly, when this cartridge is inserted, the sensing finger 92 is depressed by the cartridge base; the mechanism is devised so that movement of arm 94<SP>1</SP> in this case does not bring about withdrawal of tab 80, Fig. 5, from between collars 77, 78. Sleeve 71 is thus held away from sleeve 72, and shaft 68 is not rotated by arm 81 when the cartridge makes contact with it. Thus pinch roller 41 remains in the position shown in Figs. 4, 5. Similarly, spring 165 is not raised by the rod 166 so that tape guide 160 is not moved upwards. Track selection.-For use with either cartridge, a tape track selector button 23 is provided, and serves to raise or lower transducer 143, Figs. 1 and 4. A solenoid 120, Fig. 1, is energized and de-energized through contacts 24 actuated by pressing and releasing the button 23. At each energization, a pawl 123 moves a ratchet wheel 126 one step, so that a vertical cam surface beneath it (not shown) moves the transducer holder downwards against spring pressure, or permits it to rise by spring action. A horizontal cam 127 at the same time moves a pointer 134 over a scale 135. A variant of the tab 80 and its actuating mechanism is described (Fig. 10, not shown).