Patent GB-1357459-A (GB)
Title: Method of making ferrite matrices
IPC: G11C5/12
Filed: 1972-12-04
Abstract: 1357459 Threading memory cores VYCHISLITELNY TSENTR SIBIRSKOGO OTDELENIA AKADEMII NAUK SSSR 4 Dec 1972 55943/72 Heading B3A A method of making ferrite matrices comprises threading ferrite cores 5 in stacks 6 about at least one wire 4, the number of the ferrite cores in a stack corresponding to the number of rows 18 in the ferrite matrix to be made, (a)- (w), Fig. 1 (not shown), arranging the stacks into an' array in which the number of stacks corresponds to the number of columns of the matrix, separating one core from each stack, arranging the separated cores in a plane intersecting the wires, coiling an additional wire into a helix 9, rotating the helix through the separated cores so that the leading end of the helix passes successively through the separated cores, and straightening the helical wire to position the cores at the intersections of the wires 4 and the straightened wire, each of the cores being indexed in a desired direction. A ferrite cube, Fig. 10, is assembled from flat matrices overlying one another without soldering the wires 42 intermediate of the matrices and each matrix may feature a particular pattern. A ferrite memory may also be made in the form of a plait (36), Fig. 9 (not shown), which is cylindrical in shape. The cores in a matrix may be indexed perpendicular to each other in each row, Fig. 12, in which case the cores from respective stacks are arranged in two rows 18 according to the pitch and diameter of the helix 9. When the helix is straightened the cores 5 in each row are positioned at the intersections of the orthogonal wires. Readout-inhibition wires 41, 45, (51), (54) may be threaded alternatingly using two mechanisms 10. A core-feeding member 7 is used for receiving the cores and includes a guiding slot 8 for such a purpose. An annularlygrooved roller 12 determines the pitch of the helix. Adjacent the member 7, which may take the form of an annularly-grooved slotted roller (15), Fig. 3 (not shown), is a mechanism 10 for coiling and threading the helix wire powered by a drive 11. The mechanism 10 incorporates a spindle 23 with a cleft 24 for retaining the wire, i.e. thin insulated copper wire. An end of the spindle is received in a sleeve 26 having a thread and pitch corresponding to the helix 9 to be formed. The helix 9 is formed using resilientlybiased, internally helically grooved die-taps 28, 29. A handle 14 on feeding member 7 allows rotation of the latter with respect to the frame 1 to align slot 8 with the bottom-most cores of the stacks 6 whereupon the member is reversely rotated to release the cores. To produce matrices wherein the cores are rotated relative to one another, two feeding members 7, (7<SP>1</SP>), Fig. 4 (not shown), may be used. Also, grippers (19), Fig. 5 (not shown), may be used to allow production of matrices with any desired angular position of each core, e.g. for permanent memory devices. The electrical properties and any elimination of faults can be carried out using a pulse generator (60), Fig. 13 (not shown), and a readout amplifier (61), and any faulty core can be broken and removed from its wire 4 and the next core 5 forwarded from the respective stack. The matrices may be used for decoders, logic circuits as well as electronic computer memories.