Abstract: A trigger circuit comprises first, second and third triggerable switches each being rendered conductive when a signal at its control terminal reaches the threshold level. The first switch is connected to accept a timing pulse signal. The first and second switches are connected in series with each other and a control terminal of the third switch to activate the third switch when both the first and second switches have become conductive.A delay circuit is in series with the first switch and in parallel with the gate and one other terminal of the second switch. A time delay is introduced after the first switch is activated by the timing pulse signal and before the second switch is activated to thus trigger the third switch.

Abstract: A shut-down and first-out annunciator device comprising sensor switches that change condition when a fault occurs. Logic and display circuits provide a digital readout indicative of a fault condition. Shut-down means are responsive to a shut-down signal produced by the logic circuit and produce a latching signal for the display. A first power supply powers all sections during normal operation and a second power supply powers the display and shut-down circuits after shut-down.

Abstract: An integral spark plug coil comprising a step-up coil within a canister which canister is mounted to a unique double-walled container. The container fits over the neck of the spark plug and is secured to the shell of the spark plug. An inner ceramic bushing is arranged within a metal sleeve defining the outer wall of the container. The space adjacent the neck of the spark plug is in communication with the exterior of the metal sleeve through the small quenched space defined by the inner diameter of the sleeve and the outer diameter of the ceramic bushing and through ports in the sleeve located generally outward of the terminal end of the neck of the spark plug.

Abstract: An integral spark plug coil comprising a step-up coil within a canister which canister is mounted to an aircraft-type spark plug. The canister is secured to the barrel of the spark plug. A ceramic bushing having a hub-like shape is arranged within a metal sleeve defining part of the outer wall of the canister. The space adjacent the recessed terminal of the spark plug is in communication with ports in the metal sleeve through the small quenched space defined in part by an axial face of the ceramic bushing.

Abstract: A shut-down and first-out annunciator device comprising sensor switches that change condition when a fault occurs. Logic and display circuits provide a digital readout indicative of a fault condition. Shut-down means are responsive to a shut-down signal produced by the logic circuit and produce a latching signal for the display. A first power supply powers all sections during normal operation and a second power supply powers the display and shut-down circuits after shut-down.

Abstract: A digital hourmeter-tachometer for use with internal combustion engines or the like comprises a programmable timer for outputting system timing pulses when a d.c. power source is applied thereto. A pick-up pulse circuit generates pulses indicative of the angular speed of the device being monitored and outputs d.c. power to the remainder of the hourmeter-tachometer. A first multiple decade counter counts hour pulses outputted by the timer. A second multiple decade counter counts pulses indicative of angular speed. Display means sequentially display the output of the stored count in the first and second multiple decade counters in response to system timing pulses. A long-life battery applies a direct current to the first counter when the pulses are not received by the pick-up circuit for providing a d.c. source thereby holding the hour count. Preferably, an overspeed shut-down circuit is integrated with the above described circuit.

Abstract: A breakerless pulse generating and distributing system in which sensor-switches (such as Hall effect switches and LED triggered switches) in a distributor transmit a timing pulse to one of a plurality of series connected power switches. The sensor-switches are powered by the timing pulses being transmitted and a constant current drain is avoided.

Abstract: An electronic breakerless ignition system for an internal combustion engine. The ignition system comprises an alternating current generator synchronized with the engine. A rectifier circuit charges a storage capacitor. The storage capacitor is in series with a thyristor and the output of the ignition system, for example, a high tension ignition coil. The thyristor is triggered to discharge the storage capacitor by a voltage sensitive trigger circuit. One end of the trigger circuit is connected to the trigger terminal of the thyristor and the other end to one terminal of the generator.