| 摘要 |
1,183,692. Magnetic storage devices. SOC. INDUSTRIELLE BULL-GENERAL ELECTRIC. 20 Feb., 1968 [8 March, 1967], No. 8292/68. Heading H3B. [Also in Division H1] Bridges of isotropic magnetic material provide closed, or nearly closed, external paths for magnetic flux in both the hard and easy directions of magnetization of a planar anisotropic thin magnetic film. Several embodiments are described, each using an anisotropic magnetic film which is deposited on a flat substrate comprising a non-magnetic sheet, e.g. copper, covered with a thin gold layer. Associated with the magnetic film are orthogonal word and digit conductors which, together with the isotropic magnetic bridges and interposed insulating layers, are formed by deposition and selective etching processes in well known manner. Fig.1 shows one arrangement in which a cruciform anisotropic film 11 has its external flux path in the easy direction provided by an isotropic bridge 18 which spans the word conductor 13. The external flux path in the hard direction is through an isotropic bridge 22 which spans the digit conductor 14, the air gap between the end portions of bridge 22 and the magnetic film being minimized by polepieces 20. The magnetic flux path through the latter bridge is completely closed in the arrangement shown in Fig. 3 by providing a bridge 30 displaced in the direction of the digit conductor 14 from conductor 13. An alternative and symmetrical arrangement is shown in Fig. 2A in which the bridge spanning the digit conductor 14 is divided into two parts 25, the parts being oppositely displaced from the word conductor 13 so as to engage the pole - pieces 23, 24. A symmetrical arrangement is also obtained in the Fig. 4A arrangement in which the word conductor 35 is divided into two parallel branches 35a, 35b so as to permit bridge 34 to have its end portions in direct contact with the anisotropic film, no polepieces being used in this case. A further embodiment, Fig. 5A, uses a single cruciform bridge 37, the four end portions of which contact the limbs of a cruciform magnetic film 36, the word and digit conductors 35, 38 both being divided into two parallel branches 35A, 35B, 38A, 38B, with a single branch located under each limb of the bridge 37. Storage elements as described may be used in a storage matrix and a single anisotropic magnetic film may be common to all the elements. The matrix may be made up of two integrated sub-assemblies in contact, one subassembly comprising anisotropic films, an insulated word conductor network, and bridges providing a closed flux path for one magnetization direction, while the other subassembly comprises the digit conductor network and the bridges for the other magnetization direction. Optionally, the latter bridges may be a continuous magnetic sheet. |
