Patent GB-878448-A (GB)
Title: Data storage device
Inventor: STEMME NILS GUSTAF ERIK
IPC: G11B15/67
Filed: 1958-10-21
Abstract: 878,448. Selective record-tape apparatus. ATRIDABERGS INDUSTRIER A.B. Oct. 21, 1958, No. 33667/58. Class 40 (2). [Also in Group XIX] A memory device for computors &c. comprises a number of coils of magnetic or ferroelectric tape mounted on a carrier movable to place any selected coil in a fixed winding position where the tape is withdrawn past recording and sensing means. Fig. 1 shows a rotatable disc 1 on which are mounted 24 coils 2, the winding station being located at the bottom of the Figure. Motor 5 rotates the disc in the direction appropriate to bring the required coil more rapidly to the winding station and a photo-cell unit 14 and light source 13 switch off motor 5 and energize a brake 11 when coded apertures 7 in a skirt on the disc indicate the correct position, a pin 17 then engaging an indentation 16 to hold the unit in position. The drive pulley 20 of a motor 18 is then urged by solenoid 24 or 23 (according as the selected coil is of the inner or outer 12) into engagement with the coil shaft ready for winding off the tape (see the description below with reference to Fig. 6). Fig. 3 shows a two-dimensional square matrix 27 of 100 tape coils 2 located, by pins 28 and 29 movable in slots 33 and 37 at the intersection of two translatable rectangular frames 32 and 38, these frames being moved successively in the X and Y directions to correctly position a selected coil (relative to wind-off mechanism, not shown in Fig. 3, but shown in Figs. 5 and 6), the movement being effected by a roller 50 selectively engageable with slots 43 and 48 and stopped when the appropriately coded holes 56, 57 are detected by optical indicators 58, 59. At the wind-off point is positioned mechanism (see Fig. 5) for pushing the selected coil 2a clear of the matrix so that tape may be wound off into a container, side walls 88 and 89 of which are shown (see also Fig. 6). Each coil has a shaft 61 spring-loading it to the normal position shown, and a tube 64 rotatable for wind-off and wind-back by a motor 72 via a keyed shaft 68 be moved to the left by a motor-driven roller 81 so that socket 62 engages shaft 61 and pushes coil 2a to the left into position; roller 81 is also used to retract the spool by making it engage yoke 77 instead of 74, such engagement being effected by electromagnets 84 and 82. The forward end of yoke 74 is forked and embraces the tape before being received in a recess 91 so that the tape is guided into channels 90 in the take-off container, which as shown in Fig. 6 (the container may also be used in conjunction with the Fig. 1 embodiment) comprises guide pins 96, a record-read head 95, a drive roller 97 operative when the tape is urged against it by mechanism 99, a photo-cell arrangement 100 acting to locate desired memory positions by means of transparent portions of the tape and to control the mechanism 99, and a container portion 101 for the tape. Coil 2a is unwound at 700 r.p.m. until 100 senses the arrival of the tape, when 99 brings the drive roller 97 into operation and 2a is braked through a friction coupling; this continues until the desired memory location has been covered or the " end of tape " transparent portion is reached, when 100 acts to disengage 97 and re-wind the tape on to coil 2a and the next memory address (on the same or another coil) may be selected.