Abstract: This specification discloses a leakage reactance transformer for supplying electric arc welding current and comprising a core formed from a stack of laminations having a central `key-hole` shaped opening punched therein and defining an arcuate core portion and two spaced legs. The core has primary and secondary windings mounted thereon and a keeper secured to the legs to close the flux path of the core. One of the windings is mounted on a frame which is pivoted relative to the core so that the winding is movable along the arcuate core section towards and away from the other winding. A magnetic shunt member is also mounted on the frame approximately 180.degree. from the movable winding and in one position bridges the gap between the legs of the core and in another position is remote from this gap. In the bridging position the shunt contributes to the leakage reactance of the transformer and in the remote position contributes substantially no leakage reactance.

Abstract: A transformer for coupling between relatively moving elements having a limited degree of motion without inducing torques or forces between the elements as the result of fluxes coupling transformer windings. The transformer includes a primary and secondary coil respectively secured to the relatively moving elements and housed within a core structure of high permeability material which provides a low reluctance flux path for the mutual or coupling flux between the transformer primary and secondary windings and a relatively high reluctance path for leakage flux.

Abstract: A two-speed resolver system wherein the rotor of a fine brushless resolver which is directly connected to the shaft to be instrumented is connected to the rotor of a coarse resolver so that the rotor ofthe coarse brushless resolver rotates at a proportional but different rate than the fine resolver and the electrical output of the fine resolver which represents the position of the input shaft is fed to the electrical input on the coarse resolver and combined with the mechanical input to the coarse resolver to provide a signal out of the coarse resolver which indicates a predetermined fraction of angular rotation for each revolution of the rotor of the fine resolver. The disclosed two-speed resolver system utilizes brushless resolvers wherein the electrical connections to the rotors are through brushless rotary transformers. Two gears having a different number of teeth can be used to couple the rotor of the fine resolver to the rotor of the coarse resolver.

Abstract: A rotary transformer includes rotor and stator cores arranged apart from each other. The rotor core is made of a plurality of U-shaped core plates which are laminated around a rotary shaft and supported by a pair of plates engaged with the opposite side ends of the rotor core and by an insulative band winding the bottom of the annular recess for receiving a rotor coil.

Abstract: A digital displacement sensor includes a plurality of zigzag coils provided with projecting or convex portions having different pitches and arranged on the surface of a flat plate. A magnetic head consisting of a magnetic body and a coil is wound around part of the magnetic body, the magnetic head being supported so as to be moved, while maintaining a given gap from the surface of the flat plate, whereby a digital signal corresponding to the displacement of the magnetic head is sensed by means of a plurality of zigzag coils.

Abstract: A synchro having a rotor with windings supported by a shaft for rotation through an angle of approximately 360.degree. relative to a stator in which the rotor windings are connected to external circuitry by leads each of which is formed into a coil with a straight portion extending therefrom. The leads are disposed oppositely in a hollow portion of the shaft with the coil of each of one lead encircling the straight portion of the other lead and with the straight portions of the leads extending axially of the shaft.

Abstract: A pulse producing device has an E-shaped core with an input winding and an output winding, so that flow of flux between the limbs of the core produces an output in the windings. The flow of flux is controlled by parts rotating close to the limbs, and these parts are formed on a rotatable plate the periphery of which is split and deformed to provide two rows of tags, one row passing close to the central limb and one of the outer limbs and the other row passing close to the central limb and the other outer limb.