Patent GB-821962-A (GB)
Title: Recording apparatus
IPC: G11B17/02
Filed: 1956-12-03
Abstract: 821,962. Recording and reproducing apparatus. RAMSEY, A. R. J. (Sperry Rand Corporation). Dec. 3, 1956, No. 36913/56. Class 40 (2). [Also in Group XIX] Recording apparatus which may be used with high-speed electronic computers, comprises a frame 18, Fig. 1, in which is rotatably mounted a shaft 30 supporting a magazine 26 of records and coupled to the driving-shaft of a motor 28. Spacers 42, Fig. 7, are used to maintain the records 34 parallel to each other with interstices 44 between their recording surfaces 36, 38, while a compression-ring 46, Fig. 1, supports the magazine on the shaft 30. The spacers 42 and discs 34 may be keyed to the shaft to prevent slipping. Discs may be added to/or removed from, the pile 26 as desired. Information is stored. on the discs by magnetic recording by means of a sliding block, 70 Fig. 3, mounted in a carriage 56, guided by two rods 52 parallel with the shaft 30 and having notched stops 54, Figs. 1 and 2, corresponding to the interstices 44. The carriage may be secured in any selected position along the rods 52 by spring-stressed balls 60, Fig. 3, and supports a locating arm 62 carrying two units 64, 64<SP>1</SP>, the arm 62 being slidable between a retracted position, Fig. 1, and an extended position, Fig. 7, in which the units 64, 64<SP>1</SP> enter the selected interstice 44. Each unit 64 comprises a frame in which the block 70 is pivoted to turn about an axis parallel to the arm 62, the pivotal axis being 1/3<SP>1</SP>/ 3 x from the trailing edge 78, where x is the distance between the leading and trailing edges 76, 78. A control spring 80 tends to hold the block 70 in alignment with the frame 72. The frame 72 is pivoted within a frame 82 along an axis perpendicular to the first axis, so that the block 70 may be adjusted laterally as well as longitudinally. The frame 82 is pivoted to the arm 62 about an axis parallel with the arm 62, so that when the block 70 is within an interstice 44, rotation of the frame 82 adjusts the bearing and signalling surface of the block 70 relative to the surface 36 of the lower disc 34, while rotation of the frame 72 adjusts the longitudinal inclination of this surface 90, Fig. 8. A spring 92 stresses the frame 82 towards the signalling position. The unit 64<SP>1</SP> which is similar to the unit 64 is urged towards the lower surface 38 of the upper record 34 by a spring 92<SP>1</SP>. Within each block 70, 70<SP>1</SP> are loops 91, 91<SP>1</SP> forming a magnetic path having a gap 93, 93<SP>1</SP> near the surface 90, 90<SP>1</SP>, the loops being surrounded by energizing windings 95, 95<SP>1</SP>. The loops may be arranged with the gaps spaced laterally across the bearing surfaces 90, 90<SP>1</SP> to record and receive information simultaneously in a plurality of channels. The windings 95, 95<SP>1</SP> are connected to pairs of wires forming cables 94, 94<SP>1</SP> extending through the arm 62 to connect with a loop 96, Fig. 1, carried to the frame 18 to communicate signals. The discs 34 may be aluminium-plated with a magnetic material such as cobalt nickel alloy. The information may be recorded in concentric paths or in a spiral path by moving the arm 62 transversely of the rotating magazine 26 during recording. When the arm 62 is retracted cams 98, 98<SP>1</SP>, Fig. 3, engage the frames 82, 82<SP>1</SP> to prevent misalignment of the blocks 70, 70<SP>1</SP> by the springs 92, 92<SP>1</SP> and to act as guides for the units 64, 64<SP>1</SP> as they enter between the records. When fully retracted the arm 62 is locked by a key extending into a slot in the arm 62 from a solenoid 102, Fig. 1. On energizing the solenoid by means of cable 96, the key is withdrawn and the arm 62 released. The arm 62 is positioned by means of a cable 110 passing round guide-wheels 112, Fig. 1, and a driving drum 114. The cable ends 116, 118 are taken over guide-wheels 120, 126, respectively, Fig. 2, mounted in the carriage 56 and from these wheels the ends pass in opposite senses along grooves 124, Fig. 3, 128 (not shown) in the arm 62. To move the arm 62, the drum 114 is driven clockwise or counter-clockwise through reduction gear 132, Fig. 1, by a motor 134. When the arm 62 is locked in the retracted position, motion of the cable 110 causes the carriage 56 to move along the rods 52. When the carriage reaches the selected position, energization of the solenoid 102 unlocks the arm 62 and allows it to move between the selected records upon clockwise movement of the cable. Further movement of the cable 110 serves to adjust the arm 62, the carriage 56 being held by the balls 60. In a modification, Fig. 10, the signal-transducing heads 170 are mounted on the web of a U-shaped resilient element 168 and are urged towards the record surface by a spring 178 passing through a pivoted rod 182. When in the retracted position a cam on the carriage engages the rod 182 to take the thrust of the spring 178. In a further modification a U- shaped resilient element supports the block which is pivoted between the arms of a Y-shaped control, the stem of which is stressed by a spring. Instead of a U-shaped element, a pair of flexible elements extending from a rotatable shaft may be used to support the blocks by means of pivots.