Abstract: Starting and operating circuit for gaseous discharge lamps has device for quickly re-starting extinguished lamps while still hot. Circuit comprises a source of alternating current, an inductive regulator ballast having its input connected to the alternating current source, and a gaseous discharge lamp connected to the output of the ballast, a sine wave oscillator circuit having its input connected to the current supply and having its output connected to a transformer connected in series between the ballast and the lamp for stepping up and applying voltage to a lamp, the oscillator circuit comprising a transistor switch and an oscillator transformer connected to the step-up transformer for producing a high voltage, high frequency sine wave for starting and re-starting the discharge lamp. The operation of the oscillator circuit is improved by a turn-off circuit comprising series-connected diode and inductor connected to the transistor and the oscillator transformer.

Abstract: A precision regulated power supply for charging an energy storage capacitor wherein regulation is achieved using a triac to interrupt a connection between a primary winding of a transformer and a DC power source. The circuit is useful in a power supply for a photocopier flash lamp where precision regulation of light intensity is required. A control winding is wound on the transformer closely coupled to the power secondary winding. A triac is connected across the control winding such that the winding can be short circuited when it is desired to cease charging of the storage capacitor. Short-circuiting of the control winding collapses the voltage on the transformer secondary winding thereby inhibiting the flow of current in the secondary winding. Regulating circuitry senses the voltage on the capacitor and gates the control winding triac into conduction when that voltage reaches a desired magnitude.

Abstract: This invention discloses an electric flash device which comprises a direct current power source circuit, a flash tube circuit including a flash tube, a voltage convertor including an oscillator circuit, an oscillating transformer and an oscillation starting circuit, a rectifier circuit for rectifying an altanating current voltage from the voltage convertor and a charging circuit including a main storage capacitor for storing an electric energy to be supplied to the flash tube, a triggering circuit for firing the flash tube, said oscillator circuit includes an oscillating switching element which has a high leak resistance, and said oscillation starting circuit includes a switch element for starting the actuation of said voltage convertor.

Abstract: A dimmer suitable for use to control the intensity of illumination of a lamp or lamps for illuminating an instrument panel provided in a compartment of a vehicle such as a motor car, comprises: a dimming transistor connected to a lamp or lamps to be dimmed for controlling an electric current supplied to said lamp or lamps, a switching circuit connected to said dimming transistor for generating pulses having a controllable duty ratio to cause said dimming transistor to turn `ON` on `OFF`, surge voltage sensing means for sensing a surge voltage applied to an electric source line, and transistor shutoff means for shutting off said dimming transistor in response to a signal from said surge voltage sensing means.

Abstract: A power source circuit for a flash discharge lamp which includes a booster-rectifier, a thyristor connected to the booster-rectifier on the side of a power source, a discharge capacitor connected to the booster-rectifier on the side of a load, a detecting element for detecting a voltage across the discharge capacitor, a trigger circuit and a control circuit. The control circuit is adapted to supply, to the gate of the thyristor, an AC signal of substantially the same phase as the power source and to stop the AC signal supply when the voltage of the discharge capacitor reaches a predetermined value, thereby preventing the thyristor from noise generation which would otherwise cause a malfunction in a computer which processes facsimile or like picture signals.

Abstract: A gas discharge lamp is connected in parallel with an inductor and in series with a solid state switching device and a resistor, and this combination is connected across a DC voltage. This switching device is controlled by a monostable multivibrator, the input of which is connected to the output of a comparator amplifier sensing the difference between the voltage drop across the above mentioned resistor and the voltage of a variable reference voltage source.When the current through the inductor has increased to a point where the voltage drop across the resistor exceeds the voltage of the reference source, the comparator amplifier triggers the monostable multivibrator causing the solid state switching device to be turned off. This acts to collapse the magnetic field in the inductor thereby causing a large voltage to appear across the gas discharge lamp sufficient to light the lamp.

Abstract: The disclosed invention includes apparatus and method for full wave rectification of commerical alternating current of conventional or standard low frequency (e.g., 50-60 hz.) and for generating substantially square wave pulses of high frequency for transformation to voltage suitable for illumination of gas discharge lamps. The apparatus includes electronic means for rectification and silicone control rectifiers and stearing diodes, plus RC devices, for setting up a primary wave or pulse oscillation to produce a desired form of wave pulses at a suitable high frequency. Apparatus also includes variable potentiometer means for varying the lighting intensity by changing width or duty cycle of power pulses as applied to the primary of the light-operating transformer without substantially changing their frequency. Means which can be on or off also are included to periodically turn off the transformer power for "flashing" or periodic lighting and extinguishing of the lamps when such operation is needed.

Abstract: A simplified voltage regulating circuit is provided for controlling the operation of a d-c to d-c converter oscillator as is commonly used in an electronic flash. The voltage regulating circuit controls the operation of the d-c to d-c converter so that the output voltage from the oscillator is maintained within a prescribed range. The voltage regulating control circuitry includes an ordinary transistor controlled by way of an output voltage sensing zener diode which operates to turn on the transistor and thereby terminate operation of the oscillator when the output voltage therefrom reaches its maximum value within the prescribed range. A capacitor is also charged by way of the transistor when it turns on and the residual charge of the capacitor thereafter operates regardless of the non-conductive state thereafter assumed by the zener diode and transistor to maintain the oscillator off until the output voltage from the oscillator decays to its minimum value within the prescribed range.

Abstract: An improved energy conversion apparatus for use in charging energy storage capacitors for energizing flash lamp devices. A transformer has a primary winding coupled to a low voltage DC source and transistor switches and a secondary winding coupled to a chargeable capacitor. The transistor switches are turned on or off in response to current signals in the primary and secondary windings. A detection circuit senses the energy stored in the capacitor and supplies signals to the transistor switches to maintain energy stored in the capacitor at a predetermined level.

Abstract: In a strobe lamp system, a circuit for monitoring the amount of energy supplied to a capacitor storage bank from a power supply senses the magnitude of the current flowing to the capacitor storage bank and produces an integral function indicating the charge stored on the capacitor bank. This integral function and the voltage across the capacitor bank are monitored by a comparator. When a selected amount of energy has been stored, a switching circuit is activated by the comparator to disconnect the capacitor storage bank from the power supply.

Abstract: A flasher circuit is disclosed for use with a conventional automotive turn signal system. The flasher circuit comprises a flasher relay under the control of a free-running multivibrator. The multivibrator takes the form of a pair of intercoupled logic gates and an inhibiting means, in the form of a logic gate, disables the multivibrator when the turn signal switch is open and enables it so long as the turn signal switch is closed. The inhibiting logic gate is supplied with logic signals from the output of the multivibrator and a voltage sensing circuit connected with the turn signal switch. The flasher circuit is a two-terminal device and may be substituted for the well known hot-wire flasher without the circuit changes in the turn signal system. The logic gates preferably take the form of an integrated circuit on a single chip.

Abstract: A system for controlling machining pulse on-off time to limit gap power in response to a short or an open circuit machining gap condition in electrical machining systems wherein a multivibrator applies a preset on-off time at an electronic switch between the power supply and the gap. The condition detected at the gap in the form of an electrical signal is delivered via a delay network to a control circuit adapted to shunt one of the impedances of the resistance-capacitance network of the multivibrator.