Abstract: A control circuit for a DC inverter for an induction motor comprises:circuitry to produce a control waveform characterized by a sequence of pulse groups wherein the durations of the pulse groups increase with time, and wherein the widths of the pulses within each group increase with time, the circuitry supplying the waveform to the inverter.The circuits typically includes:(i) a first oscillator having a sawtooth output,(ii) a ramp generator having a voltage output which changes with time,(iii) a first comparator operatively connected with and responsive to the first oscillator and ramp generator outputs to produce an output characterized by a duty cycle which increases with time, and(iv) a second oscillator responsive to the comparator output to produce an output having a frequency which increases with time.

Abstract: A method and apparatus for regulating the output flux generated by a lamp with the degeneration of the voltage from a power source such as a battery. The regulating circuit maintains a constant luminous flux output from a lamp over a substantial range of voltages by switching the voltage to the lamp on and off at a preselected and controlled duty cycle. The duty cycle varies with the variations in the lamp electrical operating parameter provided to the regulating circuit. The regulating circuit permits the useful life of a power source to be substantially increased before requiring replacement.

Abstract: A warning light system constructed of an array of flashable, warning lights. The warning lights are self-contained, battery powered warning lights that may be arranged in an array and controlled to flash simultaneously. Each light includes an individual transceiving system for transmitting a coded, radio frequency signal to each other light of an array and a receiving radio frequency signal from each other light of the array to cause each lamp of each light to flash on and off in synchronism. Each light has a built-in transceiving antenna arranged within the light lens assembly and completely housed therein.

Abstract: An electro-optical wheel alignment system for vehicles includes a coaxially disposed radiant energy source and detector in which the source and detector are axially spaced apart and the source is physically small and provides a modulated output. The source and detector are adjustably disposed on the component of an automobile to be positioned in a predetermined attitude with respect to a reference device that is, in turn, positioned in a predetermined attitude with respect to the vehicle, such device comprising a radiant energy reflecting planar surface.

Abstract: This invention is directed to an off-the-vehicle type of wheel-tire balancer for vehicular wheels. A wheel and tire assembly which is to be balanced is disposed on a rotating shaft under the control of a signal responsive electronic control apparatus utilizing rotational velocity signals, rotational, directional, and positional signals and velocity of displacement of the mounting apparatus for the shaft to provide a suitably calibrated indicators, the amount of weight to be added at certain angular positions on the inner and outer planes of the wheel rim to provide a dynamic balance of the wheel-tire system. Further indicators are provided for relating the indicated weight to be added to an angular position of the wheel and tire system. The entire apparatus is automatic in operation in that once the system is started, a motor is energized to rapidly rotate the wheel-tire system up to a predetermined rotational velocity.