Abstract: Disclosed is a power and start system for use with an aircraft engine having a shaft, systems requiring AC power and systems requiring DC power. The system includes an AC/DC starter/generator mechanically coupled to rotate in response to rotation of the engine shaft while the engine is operating in generate mode. Rotation of the starter/generator produces AC and DC power and operates to rotate the shaft of the engine when the engine is in start mode. The system includes a generator control unit which is electrically coupled to the AC/DC starter generator. The generator control unit is also electrically coupled to the systems requiring DC power. A start inverter is configured to be coupled to a DC power source. The start inverter is coupled to the AC/DC starter/generator to provide power for start mode operation. The disclosed system provides multiple levels of redundancy when in the event of a failure to any one or combination f components.

Abstract: A method and an apparatus for preventing freezing at the outlet of a fire extinguisher are disclosed. Moisture in the fire extinguisher fluid is removed by contacting the fluid in the fire extinguisher bottle with a desiccant such as molecular sieve 3A. After the fluid in the extinguisher has been in contact with the desiccant for a week, the moisture level is about 5 ppm, well below the 40 ppm which causes freezeup at the outlet. The desiccant is preferably placed inside a metal screen tube having metal wire loops extending from the sides of the mesh tube. The wire loops keep the mesh tube away from the outlet so that flow restriction will not occur. The wire loops also protect the desiccant from being damaged when the fire extinguisher is discharged and provide a handle which can be used to pull the metal screen tube out of the bottle during refurbishment.

Abstract: A dimmable electronic ballast for a gas discharge lamp utilizing a modified self-resonant split inductor configuration. The voltage supplied to the lamp load is controlled by varying the duty cycle of the output stage which, in turn, feeds back a driving signal to the boost converter to synchronize the DC voltage with the needs of the load. The circuit also performs power factor and THD control. The ballast circuit controls the start-up of the lamp by proving a warming current to the filaments and then boosts the voltage to strike the lamps. If the lamps are at end-of-life wherein the filaments are intact but vapor and coatings are diminished, the ballast will apply bursts of higher voltage until the lamp strikes. Additionally, if the filaments are open, the circuit stops operation.

Abstract: A ring-shaped bearing failure sensor constructed of insulation and electrically conductive material utilizing printed circuit board technology. Because of its construction, high dimensional tolerances can be achieved and the ring can be easily assembled as a component of a generator. Further, the bearing sensor is equipped with a resistor so that the operational readiness of the sensor can be monitored.

Abstract: An improved ballast circuit for use with a compact fluorescent lamp includes an EMI filter, a rectifier and a voltage amplification stage, an active resonant circuit, a dimming circuit, and a power factor correction stage which is connected in parallel to a lamp load. In one embodiment, the ballast circuit operates in cooperation with a three way switch to adjust the light output of the lamp to three discrete levels corresponding to each setting of the three way switch. In another embodiment the ballast circuit includes a feedback capacitor which provides a feedback path for a portion of the high frequency current to the rectifier and voltage amplification stage. In still another embodiment, the ballast circuit is configured to accept input from a triac or a SCR device. In all of the embodiments, the dimming circuit works with the active resonant circuit to vary the amount of power that is supplied to the lamp load.

Abstract: An interrupter in a pyrotechnic system for selectively arming or disarming a detonation propagation transfer line comprises a mechanism for driving a barrier to and from safe and arm positions using safe and arm actuators. The motion of each of the actuators is damped to prevent cycling from external transient forces. A safety mechanism comprises a mediate member slaved to the drive mechanism and a lock member. A safing key is inserted into the interrupter to drive the lock member into a position which limits the motion of the mediate member whereupon an attempt to drive the barrier from a safe position will be blocked by the lock member. The safing key will be captured in the interrupter such that it cannot be removed until the barrier is returned to the safe position. In the preferred embodiment, the barrier comprises a rod having a non-circular transverse slot disposed between the line segments.