| 摘要 |
824,435. Magnetic data-storage apparatus. TELEREGISTER CORPORATION. June 24, 1957, No. 19858/57. Class 106 (1). In information storage apparatus comprising concentric record tracks on a rotatable carrier for magnetically storing information signals to be cyclically scanned, a transducer head is selectively moved into scanning relation with a desired track and a pick-up head is simultaneously moved into scanning relation with a corresponding cyclical source of timing pulses synchronized with respect to the pulses to be recorded on or reproduced from the selected record track. The storage device shown comprises magnetically coated discs 1, 2, &c., fixed to rotating shaft 3 which also drives, through worm gearing 5, 6 and a friction clutch, a shaft 8 to position head-carrying arms 18 through cam 10, slide rod 12 and lever 15 fixed to rock shaft 16. The shaft 8 is stopped in a selected angular position by a known form of selecting mechanism fixed to frame 21 and comprising twoposition notched code discs 40 which are selectively actuated by fingers 44, e.g. controlled by magnets (not shown) selectively energized in accordance with a teleprinter type code, so as to align notches opposite one of the differential stop pins 41. The pin thus selected is enabled to move radially inwards to engage arm 43 on shaft 8. The arms 18 (except the end arms 18a, 18b) each carry two heads 19 (not shown) and 20 which are associated with the disc on the left and right respectively, all the heads 19 registering with circular tracks of one radius on all discs, and all the heads 20 with tracks of a different radius, for each selected position. Data is recorded on the tracks in binary form with substantially uniform packing, whereby synchronizing pulses of different frequency are required for tracks of different radius. Such pulses are obtained from one of the heads 19 and one of 20 scanning permanent recordings on associated disc faces, and may be supplied to an electronic counter. The heads are connected through conductors 45 to gating and amplifier circuits (not described in detail). The cam 10 is preferably so designed that equal arcs of rotation cause corresponding equal arcs of movement of shaft 16. As a modification, the cam may be heart-shaped, one side of the heart selecting odd-numbered, and the other side even-numbered, tracks. An alternative form of selecting mechanism comprising internally notched code rings is referred to. |
