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...During the Civil War, the Confederacy established its own Patent Office which issued 266 patents, a third of which concerned implements of war.
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| Number | Title | Issue Date |
| 7936137 | Inverter A soft start circuit generates a soft start voltage Vss which changes with time at a starting time of lighting an EEFL. A pulse width modulator generates a PWM signal Vpwm whose duty ratio is feedback-controlled so that a feedback voltage Vfb corresponding to an out... | 05/03/2011 |
| 7332874 | Discharge lamp ignition device To provide a discharge lamp ignition device to light high-intensity discharge lamps in which, during alternating current ignition, the fluctuation of luminous flux on the reversal of polarity of the voltage impressed on the lamp is minimized and in which steady ligh... | 02/19/2008 |
| 6972521 | Low-pressure gas discharge lamp having a mercury-free gas filling with an indium compound A low-pressure gas discharge lamp provided with a gas discharge vessel containing a mercury-free gas filling with an indium compound in an amount of about 1 to 10 microgram per cubic centimeter and a partial pressure in the range from 1.0 to 30 micro bar, and a buff... | 12/06/2005 |
| 6958583 | AC voltage control circuit The inventive control circuit 40 serves to render the output voltage to be the output value of any one of the outputs OUT1 to OUT5 when both the main power source A of the power saving device 100 and the control circuit's switch B are in ... | 10/25/2005 |
| 5461345 | Frequency synchronous circuit for reducing transition period from power on state to stable state A frequency synchronous circuit has a first selection unit, a first counter unit, a second counter unit, a storage/average unit, and a comparison unit. The first selection unit is used to select one sampling signal from a first sampling signal having a fi... | 10/24/1995 |
| 5420481 | Fluorescent lamp with wide range of luminous intensities An apparatus is provided for controlling the luminous output of a fluorescent lamp over a wide dimming range. The luminous output is controlled by controlling the lamp current, while the lamp is immersed in a lateral electrostatic field. The lamp and exte... | 05/30/1995 |
| 4859914 | High frequency energy saving ballast A circuit is disclosed for energizing electrical devices such as fluorescent lamps and other gas discharge luminescent devices. The circuit provides energizing signals for gaseous discharge tubes at a voltage sufficient to initiate ionization of the gases... | 08/22/1989 |
| 4651059 | High-frequency power-limited lighting system A lighting system for a suspended ceiling comprises a central high-frequency power source feeding a plurality of power conditioning units permanently wired-in and mounted in various locations on the permanent ceiling above the suspended ceiling. Each such... | 03/17/1987 |
| 4081719 | Double ended thyratron with trigger impulse means The invention provides a double ended thyratron arrangement in which at each end of the thyratron there is a cathode, at least one intermediate grid and a final grid which borders a high voltage withstanding gap. At each end of the thyratron the final gri... | 03/28/1978 |
| 4075537 | Ignition electrode arrangement for gas discharge lamps, particularly for flash tubes The invention concerns an electrode arrangement for improving the ignition readiness of gas discharge lamps, particularly for flash tubes. The ignition electrodes consist of a plurality of wire loops which surround the surface of a gas discharge tube. The... | 02/21/1978 |
