Abstract: A frequency, voltage and waveshape converter is placed between the terminals of an ordinary single-phase power line and the power input terminals of a three-phase induction motor. The converter is operable to provide to the power input terminals of the induction motor a three-phase AC voltage of frequency, magnitude and/or waveshape controllably different from those of the power line voltage, thereby to permit effective control of motor speed and power factor. The frequency of the AC voltage is adjustable over the range of 12-120 Hz, with the effective magnitude of the AC voltage being automatically adjusted in proportion therewith, thereby providing for a very wide range of motor speed control without incurring reduced motor operating efficiency.

Abstract: In a fluorescent lamp ballast, a source of high-frequency voltage is applied directly across a series-resonant L-C circuit. The fluorescent lamp is connected in parallel with the capacitor of the L-C circuit and a voltage-limiting means is operative to prevent the series-resonant L-C circuit from overloading the voltage source during any period when the lamp is not effective in providing circuit loading. When power is initially applied to the series-resonant L-C circuit, a control means provides a short circuit across the capacitor; and, by way of a first current transformer, the resulting short circuit current is used for pre-heating the fluorescent lamp cathodes. After about 1.5 second, the control means provides for removal of the short circuit for a period of about 25 milli-seconds, thereby permitting the voltage across the capacitor to grow to a magnitude sufficient to ignite and operate the lamp.

Abstract: A power supply is plugged into an ordinary household electrical outlet and conditionally provides a high frequency current at a power receptacle operative to receive the power plug of an ordinary table lamp; which table lamp has a special fluorescent lamp screwed into its lamp socket. Provided the special fluorescent lamp is indeed screwed into the lamp socket, and provided the lamp's switch is in its ON position, the power supply does in fact supply high frequency current from its power receptacle; which high frequency current powers the special fluorescent lamp at a nominal power level, thereby to provide for high-efficacy luminous output. A storage battery contained within the power supply is kept fully charged by current derived from the power line voltage normally present at the electrical outlet and functions such as to cause high frequency current to be supplied from the output receptacle even if the power line voltage were to be disrupted.

Abstract: In a fluorescent lamp ballast, a source of high-frequency voltage is applied directly across a series-resonant L-C circuit. The fluorescent lamp is connected in parallel with the capacitor of the L-C circuit and a voltage-limiting means is operative to prevent the series-resonant L-C circuit from overloading the voltage source during any period when the lamp is not effective in providing circuit loading. When power is initially applied to the series-resonant L-C circuit, a control means provides a short circuit across the capacitor; and, by way of a first current transformer, the resulting short circuit current is used for pre-heating the fluorescent lamp cathodes. After about 1.5 second, the control means provides for removal of the short circuit for a period of about 25 milli-seconds, thereby permitting the voltage across the capacitor to grow to a magnitude sufficient to ignite and operate the lamp.

Abstract: In an electronic ballast, a half-bridge inverter is powered from a DC voltage and provides a nominal 30 kHz square-wave-like inverter output voltage. The inverter output voltage is applied to a series-resonant LC circuit. Parallel-connected across the tank capacitor of this LC circuit are plural series-combinations, each consisting of an instant-start fluorescent lamp series-connected with a current-limiting capacitor. The magnitude of the high-frequency voltage present across the tank capacitor is controlled by controlling the frequency of the inverter output voltage. Prior to lamp ignition, the magnitude of the high-frequency voltage is controlled to a relatively high level, such as to provide for sufficiently forceful lamp ignition. After the lamps have fully ignited, to enhance overall efficiency, the magnitude of the high-frequency voltage is reduced to a relatively low level. This low level is too low to provide for lamp ignition but sufficiently high to permit proper lamp operation.

Abstract: A half-bridge inverter is powered from a constant-magnitude DC supply voltage and provides at the inverter's output a first AC output voltage that is describable as a modified squarewave voltage. This first AC voltage is applied across a series-combination of an inductor and a capacitor, the junction between which is clamped to the DC supply voltage. As a result, a second AC voltage gets established across the capacitor; which second AC voltage is also describable as being a modified squarewave voltage. However, the phasing of the second AC voltage is delayed by approximately 90 degrees with respect to the first AC voltage; which results in the voltage across the inductor being of approximately sinusoidal waveform. A fluorescent lamp is connected in series with a ballast capacitor; and the lamp-capacitor series combination is connected across the inductor, thereby resulting in a nearly sinusoidal current being provided to the fluorescent lamp.

Abstract: An inverter-type electronic ballast for a gas discharge lamp is powered by a DC supply voltage provided from a rectifier-filter combination connected with an ordinary electric utility power line. The absolute magnitude of the DC supply voltage is higher than the peak absolute magnitude of the power line voltage. The ballast includes an inverter circuit operative to provide an inverter output voltage of special trapezoidal-like waveshape; which output voltage is applied to a series-resonant combination of an inductor and a capacitor. The gas discharge lamp is connected in parallel with the capacitor. The inverter is driven by a voltage of special waveshape and controllable frequency. By controlling the frequency, the magnitude of the current supplied to the gas discharge lamp can be adjusted, thereby correspondingly adjusting the amount of light produced by the lamp.

Abstract: A special storage battery has a pair of output terminals and a separate pair of input terminals. Comprised within the special battery is a sealed maintenance-free automotive-type storage battery with a pair of battery electrodes. A compact inverter-type battery charger is connected between the input terminals and the battery electrodes, and a control arrangement is connected between the battery electrodes and the output terminals.The input terminals are provided in the form of a recessed male receptacle adapted to connect with: i) a 120 Volt/60 Hz power line by way of a power cord having a female plug means at its one end and an ordinary power plug at its other end, or ii) a 12 Volt/DC source by way of a power cord having a female plug means at its one end and exposed conductors at its other end.The battery charger is operative to provide battery charging in an automatic manner from either 120 Volt/60 Hz or 12 Volt/DC.

Abstract: A lighting system comprises a number of central power supplies, with each central power supply being powered from a 277 Volt/60 Hz power line and operative to provide a voltage output of 277 Volt RMS magnitude and 30 kHz frequency to each of a plurality of special incandescent lighting fixtures.Each special lighting fixture comprises: i) an incandescent lamp designed to be properly powered by a voltage of 24 Volt RMS magnitude, and ii) a transformer operative to convert the 277 VoltRMS/30 kHz voltage to a 24 VoltRMS/30 kHz voltage.The reason for using 24 Volt incandescent lamps is that, at the lumen output levels normally required of light bulbs used in general lighting applications, an incandescent light bulb designed for and operated on 24 Volt RMS exhibits substantially higher efficacy and/or durability for a given lumen output level as compared with a light bulb designed for and operated on 277 Volt RMS (or 120 Volt RMS).

Abstract: Connected in circuit between the battery and the light bulb in a flashlight is a slide switch and an electronic forward converter. The slide switch has an OFF-position, an ON-position, and a spring-loaded variable BOOST-position. In full BOOST, the electronic forward converter operates such as to increase the magnitude of the voltage applied to the light bulb by a factor of about 1.5; thereby increasing the light output from the flashlight by a factor of about 4.0. However, at that degree of BOOST, if indeed maintained on a continuous basis, the life of the light bulb will be shortened to about 15 minutes versus about 50 hours when used in the normal ON-position.

Abstract: A compact folded fluorescent lamp and a small incandescent lamp are both mounted on an ordinary Edison-type screw-base capable of being screwed into an ordinary lamp socket at which ordinary AC power line voltage is controllably provided. An inverter-type ballast is integrally combined with the base and is operable to power the fluorescent lamp whenever the base is indeed screwed into the lamp socket. The incandescent lamp is powered from the AC power line voltage by way of an SCR whose conduction angle is controlled such as to cause the total light provided from the combination fluorescent-incandescent lamp to remain substantially constant from the very first moment that AC power line voltage is provided at the lamp socket. Thus, when the AC power line voltage is initially provided, the light provided from the incandescent lamp will be at its maximum while the light provided from the fluorescent lamp will be at its minimum.

Abstract: A first half-bridge inverter is powered from an unfiltered full-wave-rectified ordinary 60 Hz electric utility power line voltage. This first inverter provides at a first inverter output, across which is series-connected a first tuned L-C circuit, a first squarewave voltage of fundamental frequency between about 30 and 33 kHz; which first squarewave voltage is magnitude-modulated at 120 Hz. The first tuned L-C circuit, which is series-resonant at about 30 kHz, is parallel-loaded by a full-wave high-frequency rectifier whose DC output is applied to substantially constant-magnitude DC voltage existing across a pair of energy-storing capacitors. At a constant 30 kHz inverter frequency, the waveshape of the current drawn from the power line is substantially that of a squarewave in phase with the power line voltage, thereby giving rise to a power factor of about 90%.

Abstract: Controlled DC supply voltage is provided to a self-oscillating FET bridge inverter ballast from a pre-converter and by way of an inductor having two separate windings on a common magnetic core--with one winding being positioned in each leg of the DC supply. The inverter is loaded by way of a parallel-tuned L-C circuit connected across the bridge inverter's output, thereby providing a special AC output voltage thereat. This special AC output voltage is characterized in that it exhibits an unusually high rate of voltage change at its cross-over points but otherwise has a substantially sinusoidal waveshape. An instant-start fluorescent lamp is connected via a current-limiting capacitor across the bridge inverter's output. The magnitude of the DC supply voltage is so chosen as to cause the magnitude of the AC output voltage to be such as to effectuate proper instant-starting of the fluorescent lamp. Because the AC output voltage is balanced with respect to ground, U.L.

Abstract: A grid is suspended some distance below a permanent ceiling. The grid has plural grid openings. Each grid opening is covered by a regular ceiling panel or by a special light-weight lighting panel. Both the ceiling panels and the lighting panels are readily installable and movable, without requiring the making or breaking of hard-wire electrical connections. Each one of the lighting panels is powered by way of an individual flexible cord-and-plug means. This cord-and-plug means is plugged into a male receptacle on the lighting panel and into a female receptacle on a special power supply mounted on the permanent ceiling above this one ceiling panel. This special power supply has several such female receptacle means and can accommodate several ceiling panels. To power all the lighting panels of a complete ceiling, several of the special power supplies are used.

Abstract: In an electronic ballast, a series-resonance-loaded half-bridge inverter is powered from a DC voltage and provides an AC voltage at an AC rail across which are connected plural lamp-ballast series-combinations, with each lamp-ballast series-combination consisting of a current-limiting capacitor series-connected with an instant-start fluorescent lamp. The DC voltage, which is obtained via a pre-converter, is controlled so as to maintain a predetermined magnitude even during the lamp ignition process. The 35 kHz AC voltage is generated by the half-bridge inverter powering a series-tuned L-C circuit near its natural resonance frequency. The AC rail is connected across the tank-capacitor of the L-C circuit. Except for being reduced so as to maintain total lamp current below a predetermined level on a sustained basis, the magnitude of the AC voltage is controlled to a given level in response to an AC control action applied to an AC control input.

Abstract: In a power-line-operated current-fed parallel-tuned electronic ballast, power-factor-correction and harmonics-reduction are attained by placing a high-frequency inductor as well as a high-frequeny voltage source in series with the DC output of a bridge rectifier connected with the power line voltage. The DC output is then supplied to a filter capacitor through a high-speed diode, thereby to provide a DC voltage of substantially constant magnitude to the ballast's inverter while at the same time drawing power from the power line with a power factor well over 90% and with a total harmonics content well under 20%. The AC voltage provided from the high-frequency voltage source, which has a peak-to-peak magnitude essentially equal to that of the power line voltage, is represented by a simple auxiliary winding on the ballast's main output transformer.

Abstract: In an electronic ballast, a half-bridge inverter drives a series-connected LC circuit near the LC circuit's natural resonance frequency. A relatively high-magnitude substantially sinusoidal 30 kHz output voltage develops across the tank-capacitor of the LC circuit. Each of several instant-start fluorescent lamps is series-connected with a current-limiting capacitor, thereby resulting in several lamp-capacitor series-combinations, each of which is connected across the tank-capacitor. The ballast is powered from ordinary 120 Volt/60 Hz power line voltage by way of a full-wave rectifier. At the DC output terminals of this rectifier exists a DC voltage having an instantaneous absolute magnitude equal to that of the power line voltage. Within the ballast, the inverter is powered from a DC supply voltage of constant magnitude about equal to the peak magnitude of the power line voltage.

Abstract: A self-contained programmable actuator can easily be mounted directly onto the outside of the face plate of a standard wall switch having a built-in light dimmer. This actuator can be programmed to adjust the position of the dimmer's mechanical control input in accordance with a program that automatically repeats on a diurnal, weekly or other cyclical basis. The actuator includes a small battery, a miniature electric motor with a gear/linkage mechanism operable to engage with and to move the dimmer's mechanical control input over its complete range, and a quartz-clock-based programming means having programming intput keys and time display means.Once programmed by way of the programming input keys, the programming means is operative to actuate the electric motor in such manner as to move the dimmer's mechanical control input in accordance with the keyed-in program.

Abstract: In a power-line-operated current-fed parallel-tuned electronic ballast, power-factor-correction and line current harmonics-reduction are attained by placing a high-frequency inductor as well as a high-frequency voltage source in series with the unfiltered DC output of a bridge rectifier connected with the power line voltage. The unfiltered DC output is then supplied to a filter capacitor through a phase-controlled field-effect transistor, thereby to provide a DC voltage of controllably constant magnitude to the ballast's inverter while at the same time drawing power from the power line with a power factor well over 90% and with a total harmonics content well under 20%.

Abstract: In an electronic ballast, a half-bridge inverter is powered from a DC voltage and provides an AC output voltage having a waveform with trapezoidally shaped half-cycles. The DC voltage is obtained by way of a pre-converter with a control input operative to permit control of the magnitude of the DC voltage. The AC voltage is applied across the primary winding of a leakage transformer, whose loosely coupled secondary winding is connected across a gas discharge lamp. The internal inductive reactance of the secondary winding constitutes a lamp ballasting means by way of limiting the magnitude of the resulting lamp current to a desired level. Prior to the flow of lamp current, the magnitude of the DC voltage is controlled by negative feedback to the control input so as to remain at a maximum level. After lamp current has started to flow, by negative feedback derived from the lamp current itself, the magnitude of the DC voltage is reduced so as to bring the magnitude of the lamp current down to the desired level.