Abstract: An improved electromagnetic scanner has a substantially E-shaped core having an outer surface that is positioned, at a predetermined air-gap spacing, from a regularly grooved ferromagnetic surface of a textile machine. A pair of coils extend around the crosspiece of the core between the outer arms of the core and the middle arm thereof, such coils being connected in series and connected to a bridge circuit to generate an electrical indication that varies at the rate of movement of the grooved ferromagnetic surface past the core in a direction crossing the grooves in the surface. The plane of said core is oblique to the grooves. A pair of abrasion-resistant, non-magnetic contact elements supported in the spaces between the arms of the core, projecting outwardly into the air gap, and are urged into contact with the moving ferromagnetic surface by a spring carried in a housing in which the core and coils are mounted.

Abstract: Electrode for a rechargeable electrochemical current source and a method of making the same, said current source employing an electrolyte, the electrode having an electrically conductive collector and a mixture of an active mass in a plastic material distributed over the collector and sintered thereon to form an integral element. The electrode has a porous layer of material covering at least a substantial portion of its active surface, the porous layer being made of an electrically non-conductive material which is chemically inert with respect to the electrolyte, the plastic material being bonded to the porous layer by being sintered thereto.

Abstract: An improved active electrode composition for a zinc electrode of an electrochemical accumulator is provided with an ingredient that inhibits the passage of zinc into the alkaline electrolyte of the accumulator during the discharge process. The ingredient is preferably an alkaline fluoride, which during discharge forms with the zinc a compound which is only slightly soluble, if at all, in the electrolyte. The resulting prevention of the reversible movement of zinc into and out of the solution is effective to prevent an undesired shifting of active material on the collector of the electrode, and generally to increase its life.

Abstract: An improved active electrode composition for a plastic-bonded electrode of an electrochemical accumulator is described. A powder of the principal electrode active material is mixed with 1.5 - 60% by weight of oxalic and/or a salt thereof. The admixture of such ingredients with a suitable binding agent may then be applied to an expanded metallic collector and then heat and pressure treated in a conventional manner to obtain the required electrode.

Abstract: The movement of each of a plurality jacks or rocking pressers of a ferromagnetic material a circular knitting machine between a knitting and a non-knitting position is accomplished by the cooperation of the fields of a permanent magnet and a selectively actuable electromagnet which are magnetically isolated from each other. The portion of the jack where such fields intersect may be recessed to accomplish jack positioning with minimum expenditure of magnetomotive force. The airgap in the pole structure of the permanent magnet and in the separate core of the electromagnet are coaxially disposed, with the electromagnet being suitably located either inside or outside the core of the electromagnet. Where outside mounting is used, the permanent magnet may be disposed on the periphery of the circular bed of the machine along with the jacks, while the electromagnet is radially spaced therefrom.