Abstract: Rotor for a magnetomotive device in the form of an annular casting having a cavity or slot formed in the periphery thereof. The cavity includes locating surfaces. A permanent magnet is held in clamping relation within said cavity between a pair of pole pieces which include arcuate pole faces coaxial with the rotor. Retaining pins disposed in registered recesses of the cavity and pole pieces hold said pole pieces in said slot and urge surface portions thereof radially against said locating surfaces which are oriented to cause the pole pieces to exert clamping forces against the magnet disposed therebetween with the pole faces disposed in coaxial relation in the rotor.

Abstract: A breakerless condenser discharge ignition system for an internal combustion engine and excited by a rotating permanent magnet, consists of a single module, containing a number of windings and electrical components, mounted on one pole of a ferromagnetic core for producing high voltage output pulses for firing an associated spark plug.

Abstract: An ignition system of an internal combustion engine is provided with a hazardous-start inhibiting interlock that prevents the engine from being started unless an associated engine clutch, transmission, brake or similar device is placed in a safe condition for starting. The ignition system has a spark plug, a secondary winding of an ignition transformer connected to the plug to provide a sparking potential and a source of low-tension current pulses supplied to the primary winding of the ignition transformer in timed relationship with the engine cycle. The hazaradous-start inhibiting interlock is connected between the pulse source and the primary winding of the ignition transformer, and at the time of engine starting the interlock blocks the flow of current pulses to the primary winding unless the clutch, transmission or other device is safely positioned so that the vehicle or other mechanisms powered by the engine cannot be set in motion.

Abstract: A permanent magnet field means for use in a dynamoelectric machine comprises a magnet ring received in a supporting ring of ferromagnetic material. The magnet ring includes a circular array of arcuate magnets and a carrier of non-magnetic material in which the magnets are fixedly embedded. The magnet ring has a single axially extending gap located between the adjacent ends of two neighboring magnets. A spreading element placed in the gap spreads the magnet ring into tight engagement with the supporting ring. In some cases, this expansion of the magnet ring is used by itself to hold the magnet ring to the supporting ring in the finished device. In other cases, an adhesive is used between the supporting ring and the magnet ring and the expansion of the magnet ring is used to hold the magnet ring tightly to the supporting ring until the adhesive sets, the adhesive thereafter being the principal agent fixing the magnet ring to the supporting ring.

Abstract: A program selector in an electronic calculator has a number of formulas which are printed in human readable form. When a formula is selected by the operator a machine readable representation of the formula is positioned adjacent a transducer. The transducer generates an electrical signal which represents an identification of the particular mathematical formula or other type of program to be executed by the electronic calculator. The electrical signal is decoded by a decoder which generates a storage address for the starting point of the formula or program to be executed.

Abstract: A capacitor-discharge ignition system for a two-stroke internal combustion engine has a trigger coil which during forward rotation of the crankshaft discharges a capacitor through the primary coil of an ignition transformer to produce an appropriately timed ignition spark. The discharge and spark occur when a magnet mounted on the flywheel of the engine intercepts the trigger coil at a crankshaft or piston position in the vicinity of top dead center. The trigger coil discharges the capacitor by supplying a trigger signal to the control gate of a silicon controlled rectifier (SCR) located in the discharging path between the capacitor and the primary coil of the ignition transformer. The primary coil, which is connected to the cathode of the SCR, is mounted on a stator core intercepted by the magnet on the flywheel no less than 60.degree. after top dead center.

Abstract: An ignition coil for use in the ignition system of a spark-ignited internal combustion engine consists of a small number of parts capable of being assembled into a complete unit by a simple assembly method. The method is such that some of its basic steps may be carried out on a batch of units at one time to reduce the per unit assembly time and expense. The coil may be either double ended or single ended with regard to its secondary winding.