A generator capable of producing electric current includes at least one stationary permanent magnet or electromagnet aligned with at least one stationary core of non-permanent magnetic material provided with an induction field coil winding. The poles of the aligned magnet and core face one another on opposite sides of a magnetic flux field suppressor in the form of a rotary disc. This disc has alternating equal width sectors of a magnetic material and sectors of a non-magnetic material, the form...

A magnetic interrupter type transducer for providing an ignition signal with alternating peaks and varying progressively between the peaks. The shape of the signal is a function of the configuration of the opposed surfaces between a rotor and an adjacent pole tip of a magnetic circuit which generates the ignition signal by electromagnetic induction. The variation in volume of the air gap produced during rotation of the rotor provides the signal of the desired characteristics.

A magnetic probe for sensing the passage of a moving magnetic element, comprising a radially magnetized cylindrical permanent magnet, formed of a flat sheet of elastomer bonded ferrite material magnetized across its smallest dimension and curled to cylindrical configuration, or formed in cup-shaped configuration. A magnetic collector core is mounted co-axially in one end of the magnet cylinder and has an axial pole piece of reduced diameter projecting to the other end of the magnet cylinder, and...

Magnetic pickup having a matrix-bonded permanent magnet sleeve around one end of an elongated cylindrical pole piece and a coil around the other end. The magnet sleeve has a preferred direction of magnetization radial to the axis of the pole piece.

A multiple coil electromagnetic pickup converts into signals the flux varions produced by the passing of the teeth of a sound wheel. The pickup comprises at least two assemblies each consisting of at least one coil, one pole piece and one straight magnet all axially aligned, the assemblies being arranged in parallel to each other and magnetically insulated from each other by a screen. Measurement of rotational speed produces two output signals.

A device for monitoring the circumferential speed of a toothed disc (1) capable of being rotated, with a sensor (4) arranged at a defined distance (s) from the toothed rim (2) of the toothed disc (1) and with a sensor casing (7) supported at and securable to a stationay guide member. In order to avoid the need of any additional adjustment of the distance (s) in the event of remounting the sensor (4), a bushing (9) is provided as a guide member which is adapted to be fastened to a carrier element...

An electromagnetic transducer which generates signals on the basis of the Barkhausen effect under periodically alternating externally applied magnetic switching fields. Prior to use, the magnetic sensor element, for example a ferromagnetic wire, is pre-magnetized by undergoing a program which subjects the wire to a coercive applied field substantially higher than the alternating interrogation field. The coercive field places different zones of the wire into magnetic saturation with varying relat...

To increase the output amplitude obtained from Wiegand wire transducers, for example of the type used in contactless ignition breaker systems, a flux concentration or flux guide element (3) of highly permeable material, for example high-frequency ferrite core material, is provided surrounding the Wiegand wire (1) and, at least in part, the pick-up coil (2) coupled thereto.

Several embodiments of tachometers generators for use in controlling the speed of electrical motor driven tools. In each embodiment a toothed rotor (28, 52, 72, 92, 122) is fixed for rotation with the motor armature shaft (23, 53, 73, 93, 124) and a sensor (31, 55, 75, 96, 126) is juxtaposed to the rotor. The sensor is comprised of a core (32, 56, 76, 98, 127) having a first end portion (33, 57, 77, 99, 128) juxtaposed at a first location relative to the rotor and a second end portion (36, 58, 7...

A switched reluctance machine (SRM) having a rotor and stator pole numerical relationship of S number of stator poles and R number of rotor poles, where R=2S-2, when S is greater than 4; provides improved power density, torque production, torque ripple, and acoustic noise, and is readily adaptable to existing hardware such as known controllers and the like.