Did You Know...
...that the inventor of the electric motor was a blacksmith named Thomas Davenport? Described as "a brilliantly unsuccessful inventor", Davenport invented the first rotary electric motor. In 1836 he headed out -- on foot -- from his Vermont home to file a patent application at the Patent Office in Washington, D.C. By the time he got there, he had squandered away his money and couldn't afford the $30 filing fee so he turned around and went home. When he later mailed in his application with money he'd raised, the Patent office was destroyed in a fire. He did finally get credit for his invention on Feb. 5, 1837.
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| Number | Title | Issue Date |
| 8022638 | LCD backlight inverter Disclosed is a liquid crystal display (LCD) backlight inverter. The LCD backlight inverter includes a lamp open detection unit outputting a first open detection voltage for a preset time period when it is determined that a predetermined lamp is open, based on a curr... | 09/20/2011 |
| 7772784 | Transformer, illuminating apparatus using the same, and display apparatus using the same A transformer arranged to be used for an illuminating apparatus includes a closed-magnetic-circuit core, a primary coil wounded around the closed-magnetic-circuit core, and multiple secondary coils wounded around the closed-magnetic-circuit core. The secondary coils... | 08/10/2010 |
| 7273296 | Back-to-back lampholder A lampholder assembly in which lampholders are supported on a bracket in a back-to-back configuration with no gap therebetween is formed of a pair of insulative lampholders, each having a generally planar back surface and an opposite front face including a lamp rece... | 09/25/2007 |
| 7271546 | Lighting device for dielectric barrier discharge lamp This invention aims to decrease the leakage current of a dielectric barrier discharge lamp, and to prevent generation of the luminance slope between both electrodes. Electrodes 3 and 4 are formed in the outer surface of the dielectric barrier discharge... | 09/18/2007 |
| 6860256 | Ignition apparatus for internal combustion engine There is provided an ignition coil alleviating an insulating load between output terminals and at inside of the ignition coil and stabilizing insulating performance by constituting two outputs from the ignition coil by the same output electrode. Specifically, the in... | 03/01/2005 |
| 6750619 | Electronic ballast with filament detection A fluorescent lamp electronic ballast for use with fluorescent lamps of the preheat or heated filament type is provided. The electronic ballast includes a multiple output DC to DC converter with a primary winding and a plurality of secondary windings for connecting ... | 06/15/2004 |
| 6534929 | Electromagnetic ballast for sequentially starting a plurality of a gaseous discharge lamps An electromagnetic ballast for sequentially starting and simultaneously operating first and second gaseous discharge lamps includes a transformer having a magnetic core, a primary winding for connection to an AC voltage source and first and second seconda... | 03/18/2003 |
| 6094015 | Illumination unit and liquid crystal display device An illumination unit comprises a high-frequency supply (1) and a low-pressure discharge lamp (2). The high-frequency supply (1) is provided with a first and a second output (13a, 13b). The outputs each deliver a HF-varying voltage with respect to ground. ... | 07/25/2000 |
| 5834903 | Double resonant driver ballast for gas lamps A power supply device for a gas filled arc-type lamp having a transformer with a core with a primary coil and a secondary coil, a power source coupled to the primary coil of the transformer core and providing a generally sinusoidal signal, a connector for... | 11/10/1998 |
| 5818181 | Neon lamp isolation transformer for mid-point commoned neon lamps A low cost power supply with enhanced safety protection for neon lamps connected in a midpoint commoned lamp configuration. The power supply has a return path which is isolated from the earth ground so that a fault current does not flow from the output te... | 10/06/1998 |
| 5517087 | Fluorescent lamp ignition circuit A fluorescent lamp ignition circuit of the type including a DC voltage stabilizer to process input voltage into a constant voltage by dropping or boosting, an inductance filter to receive output power supply from the DC voltage stabilizer and to remove su... | 05/14/1996 |
| 5173643 | Circuit for dimming compact fluorescent lamps A dimming control circuit provides power from an ac source to a compact fluorescent lamp. The circuit generally includes a resonant half-bridge inverter driven by a pulse-duration-modulated voltage, for providing a high-frequency ac voltage between the la... | 12/22/1992 |
| 4912372 | Power circuit for series connected loads A power circuit for N series connected loads according to the present invention includes N transformers having primary windings connected in series across a constant current AC source and secondary windings connected in series with the N loads. N-1 conduc... | 03/27/1990 |
| 4574222 | Ballast circuit for multiple parallel negative impedance loads A current-balancing transformer is provided to supply plural parallel-connected electrical loads, especially loads such as gas discharge lamps which exhibit negative impedance and/or non-linear impedance over at least a part of their normal operating rang... | 03/04/1986 |
| 4513226 | Electronic ballast-inverter circuit An electronic ballast-inverter circuit for powering one or more fluorescent lamps or the like includes two identical circuits operating at different DC offsets, each circuit including a tank circuit composed of a primary winding of the power transformer a... | 04/23/1985 |
| 4462380 | Enhanced spark energy distributorless ignition system A distributorless ignition system of an internal combustion engine has a supplementary spark energy module to increase spark energy. Two ignition coils each have secondary coils with split secondary center taps. Each of the primary windings is coupled to ... | 07/31/1984 |
| 4441055 | Lighting system A lighting system comprises gaseous discharge lamps (8) connected to a source (1) of regulated alternating current through current transformers (5). The primary windings (6) of the current transformers (5) are connected in series to the source (1). The ga... | 04/03/1984 |
| 4435670 | Energy conserving instant-start series-sequence fluorescent lamp system with overcurrent protection An energy-saving instant-start series-sequence fluorescent lamp system includes power-reducing capacitor means connected in series circuit arrangement with one or both lamps in a two-lamp system. A protective device is connected in circuit with a first la... | 03/06/1984 |
| 4259616 | Multiple gaseous lamp electronic ballast circuit An electronic ballast circuit for a multiple gaseous lamp load includes a feedback rectifier circuit coupled to a high frequency inverter circuit and to a DC source. The high frequency inverter circuit is also coupled to the multiple gaseous load and a va... | 03/31/1981 |
| 4185233 | High efficiency ballast system for gaseous discharge lamps Electrical lamp ballast system for starting and operating fluorescent lamps with improved efficiency. System includes high leakage reactance autotransformer having primary and secondary windings, and a ballast capacitor connected in series with the second... | 01/22/1980 |
| 4184128 | High efficiency push-pull inverters High efficiency push-pull inverters minimize undesirable energy losses usually resulting from simultaneous conduction and imperfect switching of the transistor switching means. In each of the disclosed circuits, a saturable inductor and a diode are connec... | 01/15/1980 |
| 4127798 | Lamp circuit A system for operating gas discharge lamps at high frequency from a high voltage supply, typically 115 V AC with a 160 watt, 25,000 Hz output. The system provides efficient conversion, having the capability of driving any number of lamps up to maximum wat... | 11/28/1978 |
| 4100476 | Single secondary dimming inverter/ballast for gas discharge lamps A highly efficient, energy saving ballasting and transfer circuit, utilizing a single high frequency inverter ballast unit, capable of powering multiple lamp loads from any direct or alternating electric power source, comprises a current feedback inverter... | 07/11/1978 |
| 4016477 | Novel multi-path leakage transformer and inverter ballast A highly efficient, energy saving ballasting and transfer circuit, utilizing a single high frequency inverter ballast unit, capable of powering multiple lamp loads from any direct or alternating electric power source, comprises a current feedback inverter... | 04/05/1977 |
| 3969649 | Circuit arrangement for bicycle lighting systems A circuit arrangement for bicycle lighting systems including a dynamo having an output winding. Front and rear lamps connected in series across the winding. A tap divides the winding into two parts, the lamps each connecting to a corresponding winding par... | 07/13/1976 |
| 3949268 | Ballast unit for gas discharge lamps such as fluorescent tubes or the like The disclosure relates to a ballast unit for gas discharge lamps, particularly fluorescent lamps, by which a substantially constant burning current is supplied to the lamp. The ballast unit includes a transformer mounted on a core having a defined air gap... | 04/06/1976 |
