Automatic Cut-out Or Voltage Regulator In The Cathode Or Heater Circuit Patents (Class 315/107)
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Patent number: 10916399Abstract: An electron gun and an apparatus incorporating the electron gun. The electron gun includes an electron emission element, an electrode, a control element, and a control circuit. The electron emission element is arranged to be activated to emit electron beam. The electrode is arranged to be electrically connected with a power supply to accelerate the emitted electron beam. The control element may be arranged between the electron emission element and the electrode. The control element is arranged to be electrically connected with the power supply to provide an electric field to control emission of electron beams from the electron emission element. The control circuit is electrically connected with the control element for changing the electric field provided by the control element.Type: GrantFiled: September 9, 2019Date of Patent: February 9, 2021Assignee: City University of Hong KongInventors: Fu-Rong Chen, Pei-En Li, Ying-Shuo Tseng, Yu-Chun Hsueh
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Patent number: 10257903Abstract: A signal detecting device and a light-emitting apparatus using the same are provided. The signal detecting device includes an electromagnetic generator and a first switch. The electromagnetic generator includes a first receiving terminal and a second receiving terminal to receive an input signal from the first receiving terminal and the second receiving terminal and generate electromagnetic induction according to the input signal. A first terminal of the first switch is coupled to a first signal source. A second terminal of the first switch is coupled to an output terminal of the signal detecting device. The first switch determines whether the two terminals of the first switch are conducted according to the electromagnetic induction caused by the input signal.Type: GrantFiled: March 14, 2018Date of Patent: April 9, 2019Assignee: Wistron CorporationInventors: Meng-Ru Tsai, Chih-Hsiang Chien
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Patent number: 8896209Abstract: A programmed start ballast circuit is presented having a mode control circuit to selectively switch an inverter output load to control operation for cathode preheating, step dimming and/or anti-arcing operation.Type: GrantFiled: May 9, 2011Date of Patent: November 25, 2014Assignee: General Electric CompanyInventors: Gang Yao, Bo Zhang, Ting Zhang
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Patent number: 8729831Abstract: A constant-current power source unit has a variable power source which can adjust an output voltage. To detect a voltage applied to the gas discharge tube, a voltage detection unit is provided. A power source controlling unit configured to control the voltage by adding a predetermined voltage to the voltage taken in from the voltage detection unit after the electric discharge is started in the gas discharge tube.Type: GrantFiled: August 13, 2012Date of Patent: May 20, 2014Assignee: Shimadzu CorporationInventor: Hajime Bungo
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Publication number: 20140055033Abstract: A programmed start ballast circuit is presented having a mode control circuit to selectively switch an inverter output load to control operation for cathode preheating, step dimming and/or anti-arcing operation.Type: ApplicationFiled: May 9, 2011Publication date: February 27, 2014Inventors: Gang Yao, Bo Zhang, Ting Zhang
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Patent number: 8558459Abstract: An electronic ballast for an electrical lamp (2) provided with a first (21) and a second filament (22), includes a heating device which is used to heat the filaments (21, 22) and includes a resonance circuit (5), and an evaluation unit (11) designed for the evaluation of at least one measuring value of an electrical parameter during pre-determinable adjustments of operating conditions of the resonance circuit (5). The number of filaments (21, 22) of the electrical lamp (2) in electrical contact with the electronic ballast (1) can be identified according to the measuring value, and the electrical lamp (2) can be switched on by the electronic ballast (1) according to the identified number. A method for operating an electrical lamp by an electronic ballast is also described.Type: GrantFiled: March 5, 2007Date of Patent: October 15, 2013Assignee: Osram Gesellschaft mit Beschraenkter HaftungInventors: Olaf Busse, Bernhard Schemmel
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Patent number: 8358072Abstract: A circuit arrangement is provided for operating a fluorescent lamp with a first and a second filament, the circuit arrangement including a heater for the first and the second filament, wherein the circuit arrangement furthermore includes: an apparatus for storing at least one threshold value for at least one operational parameter of the fluorescent lamp; an apparatus for determining the value of the at least one operational parameter; and a control apparatus, which is configured to activate the heater for the first and the second filament for a predeterminable period of time in the event of the at least one threshold value for the at least one operational parameter being exceeded by the determined value of the at least one operational parameter.Type: GrantFiled: May 4, 2007Date of Patent: January 22, 2013Assignee: Osram Gesellschaft mit beschraenkter HaftungInventor: Thomas Mudra
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Patent number: 8314557Abstract: At an initial stage of a discharge start, a shield electrode is connected to a ground potential via a bidirectional voltage trigger switch. Thereafter, when an electrical charge within the shield electrode flows to the ground potential, by being triggered with this potential, both terminals of the bidirectional voltage trigger switch are disconnected therebetween. Thus, at an initial stage of discharge, charging of the shield electrode is suppressed to suppress a decline in discharge, and in a sustained discharge, destabilization due to an unwanted discharge from the shield electrode to the anode can be suppressed, and using such an electrode automatically allows improving the lighting performance of a discharge lamp.Type: GrantFiled: May 2, 2008Date of Patent: November 20, 2012Assignee: Hamamatsu Photonics K.K.Inventors: Yoshinobu Ito, Koji Matsushita, Masaki Ito
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Publication number: 20120262063Abstract: A circuit configuration for powering high-frequency fluorescent lamps with rapid start capability has input terminals connected to a ballast and output terminals connected to a fluorescent lamp. A transformer module has at least one primary winding that receives a power signal from the ballast and two or more secondary windings that are magnetically coupled to the primary winding. The secondary windings power the cathodes of the fluorescent lamp. The energizing signals are at a high frequency for powering high-frequency fluorescent lamps with rapid start capability. Tuning capacitors are used for tuning the high-frequency power signals. A control device, for instance for occupancy sensing and/or daylight harvesting may be connected into the circuit so as to further raise the efficiency of the luminaire by only energizing the lamp when it is useful.Type: ApplicationFiled: April 16, 2012Publication date: October 18, 2012Applicant: ECO LIGHTING, LLC.Inventor: ANTHONY MANGIARACINA
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Patent number: 8228000Abstract: A circuit arrangement is provided, which may include an input; an output; an inverter, configured to provide an AC supply voltage from a DC supply voltage; a control device configured to drive the inverter, the control device being configured to initiate a preheating phase once a preheating criterion has been met; a resonant circuit having a resonant inductor and having a resonant capacitor; and a transformer configured to preheat electrodes of a gas discharge lamp; wherein the primary winding of the transformer is connected in series with the resonant capacitor and is connected directly to the reference potential of the control device, and an electrical switch is coupled in parallel with the primary winding of the transformer, which switch has a control connection, which is coupled to the control device being configured to transfer the electrical switch into its electrically conducting switching state once the starting criterion has been met.Type: GrantFiled: May 11, 2010Date of Patent: July 24, 2012Assignee: OSRAM AGInventor: Bernd Rudolph
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Patent number: 8203273Abstract: A ballast circuit includes a filament cutback circuit to reduce a pre-heat voltage after the lamp filaments have been pre-heated. The filament cutback circuit includes a filament cut-back inductive component magnetically coupled to the resonant inductive component in the inverter to receive a filament cutback control voltage associated with an AC voltage for powering the lamps. During the pre-heating period, the filament cutback control voltage is not high enough to charge a chargeable component to a switch threshold level. However, during lamp ignition, the filament cutback control voltage is increased and charges the chargeable component to the switch threshold level. This causes a switch device to operate in a conductive switch state and the filament cutback circuit suppresses the pre-heat voltage.Type: GrantFiled: May 12, 2009Date of Patent: June 19, 2012Assignee: Universal Lighting Technologies, Inc.Inventors: Wei Xiong, Christopher Radzinski
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Patent number: 8138676Abstract: A system for operating a fluorescent light is provided. The system comprises: a fluorescent lamp with at least one electrode having at least one corresponding heating filament; a filament signal power supply for providing a filament current signal having a filament current frequency, the filament signal power supply connected to create a filament current through the at least one filament; and a plasma signal power supply for providing a plasma power signal having a plasma power frequency, the plasma signal power supply connected to create a plasma current between the at least one electrode and a gas contained in the fluorescent lamp. The plasma power frequency is greater than the filament current frequency.Type: GrantFiled: December 1, 2008Date of Patent: March 20, 2012Inventor: Robert L. Mills
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Patent number: 8106598Abstract: Method and apparatus for assuring use of a fluorescent or similar high efficiency lamp in a screw base socket, the invention provides a circuit containing a screw base socket and an associated thermal sensing unit capable of interrupting power to the circuit on sensing of heat such as is generated by an incandescent or similar low efficiency lamp when mounted in the screw base socket. Practice of the method permits use of only fluorescent or similar lamping such as is incapable of sufficient heat generation to interrupt power to the circuit, the methodology of the invention preventing use of incandescent or similar energy inefficient lamping. The method and apparatus are particularly useful in the lamping of recessed downlighting fixtures.Type: GrantFiled: March 24, 2009Date of Patent: January 31, 2012Inventor: James P. Yates
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Patent number: 8026674Abstract: An electron source has an electron emitter with an electron emission cathode, a high voltage unit provided for power supply of the electron emission cathode, and a low voltage unit provided to control the high voltage unit. Data are transmitted non-electrically (in particular optically) between the high voltage unit and the low voltage unit.Type: GrantFiled: September 5, 2008Date of Patent: September 27, 2011Assignee: Siemens AktiengesellschaftInventors: Jan Berk, Josef Deuringer
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Patent number: 8004212Abstract: A VFD drive apparatus in which the filament of a VFD is coupled at a first terminal to an input voltage derived from a voltage source, and at a second terminal to a shunt voltage regulator that establishes a regulated filament current and a regulated cutoff voltage with respect to ground potential. Other electrical loads such as drive circuitry for the anodes and grid of the display are coupled between the second terminal of the filament and ground potential so that at least a portion of the filament current is supplied to such other electrical loads. Power dissipated by the shunt voltage regulator is thereby reduced, and the cost associated with providing additional voltage regulators for the other electrical loads is avoided.Type: GrantFiled: October 24, 2008Date of Patent: August 23, 2011Assignee: Delphi Technologies, Inc.Inventors: Wayne A. Madsen, Andrew R. Betts
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Patent number: 8004199Abstract: The method according to the present invention relates to controlling a gas discharge lamp during a pre-heating period of said lamp, wherein a first terminal of a control circuit is connected with a first electrode of the lamp and a second terminal of a control circuit is connected with a second electrode of the lamp, and wherein means are provided, suitable for connecting the first terminal and the second terminal with each other, thus providing a conducting path, and suitable for disconnecting the first terminal and the second terminal. Furthermore the method comprises the use of a chargeable and dischargeable power buffer, for powering control circuitry for operating the switching means.Type: GrantFiled: July 13, 2007Date of Patent: August 23, 2011Assignee: Koninklijke Philips Electronics N.V.Inventors: Marcel Beij, Theodoor Hubert Stommen, Bertrand Johan Edward Hontele
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Patent number: 7977894Abstract: An electronic ballast has control circuitry to provide a pre-heating signal to the filaments of a gas discharge lamp for a predetermined length of time before the lamp is ignited and, further, cease providing the pre-heating signal after the lamp has been ignited.Type: GrantFiled: January 6, 2009Date of Patent: July 12, 2011Assignee: Universal Lighting Technologies, Inc.Inventors: Wei Xiong, Christopher Radzinski
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Patent number: 7800311Abstract: At the time of restoration of the power supply after a power failure, a voltage higher than that in the normal operation mode is supplied to a heater. After a lapse of a predetermined time, the voltage to be supplied to the heater is switched into the voltage in the normal operation mode while a control signal for stating the operation of an electron tube is output. Alternatively, at the time of power activation, the rate of change of current flowing through a heater is determined for every period of time. When the rate of change becomes equal to or lower than a predetermined threshold, a voltage higher than that in the normal operation mode is supplied to the heater, and after a lapse of a predetermined time, the voltage to be supplied to the heater is switched into the voltage in the normal operation mode while a control signal for stating the operation of the electron tube is output.Type: GrantFiled: March 18, 2008Date of Patent: September 21, 2010Assignee: Netcomsec Co. Ltd.Inventors: Akira Chiba, Yukihira Nakazato
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Patent number: 7629750Abstract: A lamp driving device includes a switch circuit for supplying a signal; a transformer which boosts a voltage of the signal from the switch circuit and supplies the boosted voltage to at least one lamp; a safety circuit which compares a threshold value with at least one of the boosted voltage and a current through the lamp, and intercepts at least one of the boosted voltage and the current through the lamp in accordance with the comparison result; and a warming part for warming the lamp in an early stage with a voltage less than or equal to the threshold value.Type: GrantFiled: June 13, 2006Date of Patent: December 8, 2009Assignee: LG Display Co., Ltd.Inventors: Sin Kyun Park, Kang Ju Lee
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Patent number: 7595490Abstract: A method for operating a charged particle beam emitting device and, in particular, an electron beam emitting device including a cold field emitter is provided. The method includes the steps of placing the cold field emitter in a vacuum of a given pressure, the emitter exhibiting a high initial emission current I0 and a lower stable mean emission current IS under a given electric extraction field; applying the given electric extraction field to the emitter for emitting electrons from the emitter surface; performing a cleaning process by applying at least one heating pulse to the cold field emitter for heating the emitter surface, whereby the cleaning process is performed before the emission current of the cold field emitter has declined to the lower stable mean emission value IS; and repeating the cleaning process to keep the emission current of the emitter continuously above the substantially stable emission value IS.Type: GrantFiled: September 1, 2006Date of Patent: September 29, 2009Assignee: ICT, Integrated Circuit Testing Gesellschaft fur Halbleiterpruftechnik mbHInventors: Fang Zhou, Pavel Adamec, Jürgen Frosien, Jimmy Vishnipolsky
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Patent number: 7586098Abstract: A system and method for developing a solid state stripper device is described that more effectively strips off negative carbon ions to produce positively charged carbon ions. In one embodiment the solid state stripping device is a self-supporting aggregate of nanotubes or Buckminster-Fullerenes. Such devices provide, among other things, carbon stripper foil for use in a tandem generator.Type: GrantFiled: July 26, 2005Date of Patent: September 8, 2009Assignee: Woods Hole Oceanographic InstitutionInventors: Karl von Reden, Enid Sichel
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Patent number: 7586730Abstract: An electron bombardment heating apparatus, in which thermions emitted from filaments are accelerated and impinge upon a heating plate, so as to heat the heating plate, wherein a peripheral wall of a heated material supporting member having a heating plate as a ceiling thereof is made of multi-staged peripheral wall portions, positioned vertically and having a different radius, and those peripheral wall portions are connected with each other by means of a ring-like horizontal wall. With this, thermal stress can be mitigated, which is caused due to a difference in temperature between the lower end portion of the heated material supporting member and the heating plate when heating up the heating plate, thereby causing no breakage in the heated material supporting member when conducting heating and cooling upon the heating plate, repetitively.Type: GrantFiled: June 1, 2006Date of Patent: September 8, 2009Assignee: Sukegawa Electric Co., Ltd.Inventor: Shigetaka Haga
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Patent number: 7576494Abstract: The present invention applies to provide a lighting method of a high pressure discharge lamp dedicated particularly for image equipments in which re-lighting when turning ON the switch again immediately after the switch OFF is instantaneously performed even in the high pressure discharge lamp. In the transition state of transitioning from the lighted state to light off, the lamp power to be supplied to the electrodes (3), (4) is reduced to an extent an arc discharge does not disappear and maintained for a while, and thereafter, transitioned to the glow discharge after lowering the lamp temperature to a temperature capable of maintaining the glow discharge and maintaining the glow discharge for a while, and the current supply to the electrodes (3), (4) is cut at the point the lamp temperature becomes lower than or equal to the temperature at which re-lighting is possible.Type: GrantFiled: September 28, 2004Date of Patent: August 18, 2009Assignee: Phoenix Electric Co., Ltd.Inventors: Atuji Nakagawa, Toshitaka Fujii, Hisao Furukawa, Kouichi Odani
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Patent number: 7560868Abstract: A ballast (10) for powering at least one gas discharge lamp (70) having heatable filaments (72,74) includes an inverter (200), a resonant output circuit (400) coupled between inverter (200) and lamp (70), and a filament heating and ignition control circuit (600) coupled to inverter (200) and resonant output circuit (400) having a first resonant frequency and a second resonant frequency, wherein the first resonant frequency is substantially greater than the second resonant frequency. Filament heating and ignition control circuit (600) controls inverter (200) and resonant output circuit (400) during a preheat phase and during a normal operating phase. During the preheat phase, resonant output circuit (400) has an effective resonant capacitance corresponding to the first resonant frequency, and provides a first level of heating to the lamp filaments (72,74).Type: GrantFiled: May 11, 2007Date of Patent: July 14, 2009Assignee: Osram Sylvania, Inc.Inventors: Qinghong Yu, Joseph L. Parisella
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Patent number: 7544951Abstract: A device which employs an electron beam, for performing a desired function, includes an electron gun for generating the electron beam. The electron gun includes a barrel shaped rotatable structure having a plurality of annularly disposed electron sources. A curvature of a surface portion of the rotatable structure is shaped to optimize electric field concentrations. The rotatable structure further includes end portion protrusions.Type: GrantFiled: July 31, 2006Date of Patent: June 9, 2009Assignee: NuFlare Technology, Inc.Inventors: Rodney Kendall, Tomohiko Abe
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Patent number: 7355348Abstract: The invention relates to a novel ballast for a discharge lamp, in which a continuous-operation control circuit is brought out of operation when a physical operation, which defines a preheating time, of a preheating timer has as yet not been sufficiently returned if the lamp is intended to be restarted.Type: GrantFiled: May 24, 2005Date of Patent: April 8, 2008Assignee: Patent-Treuhand-Gesellschaft für Elektrische Glühlampen mbHInventor: Bernd Rudolph
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Patent number: 7339322Abstract: Apparatus and methods are disclosed for measuring cathode fall within a fluorescent lamp that contains an electrode and a gas. A level of cathode fall associated with the electrode may be identified based on an intensity and wavelength of radiation emitted by the gas.Type: GrantFiled: August 21, 2006Date of Patent: March 4, 2008Assignee: Lutron Electronics Co., Inc.Inventors: John Francis Waymouth, Robert Thomas Nachtrieb, Farheen Khan, Mark Alan Hartfield, Mark Stephen Taipale, Renzo Corrado DeMeo, Russell Lawrence MacAdam
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Patent number: 7268496Abstract: When a discharge lamp is preheated, impedance of a filament electrode of the discharge lamp is computed. In accordance with the computed impedance, preheating and lighting of the discharge lamp are controlled.Type: GrantFiled: December 20, 2005Date of Patent: September 11, 2007Assignee: Toshiba Lighting & Technology CorporationInventors: Yuuji Takahashi, Kazutoshi Mita, Masahiko Kamata
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Patent number: 7256549Abstract: A method of operating an arc discharge lamp that has first and second electrodes is described. First, the first electrode is heated with a third electrode with a first arc until the first electrode temperature is sufficiently elevated to allow for thermionic emission. Then, a first voltage is applied between the first and second electrode at a voltage less than 1000 volts to create a second arc.Type: GrantFiled: March 9, 2006Date of Patent: August 14, 2007Assignee: Hewlett-Packard Development Company, L.P.Inventors: Donald L. Michael, Matthew Beasley
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Patent number: 7199526Abstract: An electronic ballast capable of extending life of the fluorescent lamp is disclosed. The electronic ballast according to the present invention comprises a DC/AC converter, a fluorescent lamp, a transformer, a preheating transformer and an AC switch. Wherein, the AC switch is turned off during a preheating period of time for the fluorescent lamp. Due to adoption of a preheating transformer in the secondary side and an AC switch for the electronic ballast according to the present invention, the voltage drop across the fluorescent lamp can be reduced during the preheating period of time, and accordingly no glow current would appear. Therefore, life of the electronic ballast can be effectively extended.Type: GrantFiled: May 6, 2005Date of Patent: April 3, 2007Assignee: Delta Electronics, Inc.Inventors: Chenyang Liu, Xiaoju Hu, Yuanyuan Zhong, Jianping Ying
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Patent number: 7193367Abstract: An indirectly heated cathode C1 comprises a heater 1, a double coil 2, a mesh member 3, and a metal oxide 10. An electrical insulating layer 4 is formed on the surface of heater 1. Heater 1 is inserted into and positioned at the inner side of double coil 2. Mesh member 3 is disposed along the length direction of double coil 2 at the outer side of double coil 2. Double coil 2 is grounded by being connected to the ground terminal of heater 1 via a lead rod 7. Metal oxide 10 is held by double coil 2 and disposed to be in contact with mesh member 3. Metal oxide 10 and mesh member 3 are exposed to the outer side of indirectly heated electrode C1 so that the surface of metal oxide 10 and the surface of mesh member 3 make up a discharge surface and mesh member 3 is in contact with the surface part of metal oxide 10.Type: GrantFiled: December 13, 2001Date of Patent: March 20, 2007Assignee: Hamamatsu Photonics K.K.Inventor: Koji Kawai
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Patent number: 7106008Abstract: A flashlight control circuit is provided to control the flash according to an exposure voltage and a predetermined voltage. Either a first comparator, second comparator and logic gate or a comparator, a first inverter, a first transistor, a first logic gate and a second logic gate may be included in the control circuit. The provided circuit enables the capacitor to discharge promptly when the trigger signal stops. Therefore, an additional control signal for discharge is not necessary. Furthermore, the circuit has a clamping circuit to clamp the exposure voltage at a lower level than the predetermined voltage according to a full flash signal.Type: GrantFiled: August 31, 2004Date of Patent: September 12, 2006Assignee: Leadtread Technology Corp.Inventors: Yu-Shan Chu, Ming-Nan Chuang
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Patent number: 6965237Abstract: A detecting device for detecting electromagnetic waves generated by electric facilities includes a support having a peripheral surface for attaching a number of wave detectors which detect the electromagnetic waves generated by the electric facilities. The support may include a housing having a chamber for receiving the electric facilities, or having a curved outer peripheral surface for supporting the wave detectors. The wave detectors each has a number of light devices for indicating the strength of the received electromagnetic waves.Type: GrantFiled: September 27, 2002Date of Patent: November 15, 2005Inventors: Shu Shoung Kuo, Shu Ling Kuo
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Patent number: 6936970Abstract: In accordance with one aspect of the present application, a lamp inverter circuit includes a switching portion that converts a bus voltage signal into an alternating current signal. An input portion receives the bus voltage signal, and a resonant load portion drives a lamp. A preheating portion heats the lamp prior to ignition, and thereafter renders itself inactive following ignition of the lamp. In accordance with another aspect of the present application, a method of starting a lamp includes receiving a bus voltage signal, converting the bus voltage signal into an alternating current signal, preheating the lamp to an ignition temperature, igniting the lamp and inactivating the preheating after the lamp has been ignited. In accordance with another aspect of the application, provided is a method of igniting an auxiliary lamp, including detecting a conductive state of a main lamp in a lamp ballast circuit, the detecting being by a switch that controls preheating of the main lamp.Type: GrantFiled: September 30, 2003Date of Patent: August 30, 2005Assignee: General Electric CompanyInventors: Timothy Chen, James D. Mieskoski, Didier G. Rouaud, Scott Brandonisio
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Patent number: 6838834Abstract: An electronic ballast of a lighting system includes an output power supplier and a heater power supplier. The output power supplier is configured to supply electric power to a lamp of the lighting system. The heater power supplier is configured to provide substantially a rated voltage of a heater of an insulation detector to the heater even though a voltage of an electric power source for the lighting system is different from the rated voltage of the heater.Type: GrantFiled: December 27, 2002Date of Patent: January 4, 2005Assignee: Matsushita Electric Works, Ltd.Inventor: Masanao Okawa
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Patent number: 6812920Abstract: A display device which is suitable for connection to a computer etc. allows an operator to freely set a power saving mode to suppress the wasteful consumption of power. Power reduction means reduces, in a plurality of modes, the power supplied to device components included in the display device. Power management output selecting means sets any of the plurality of modes on the basis of a selection made by an operator. Signal detecting means monitors horizontal and vertical synchronizing signals sent from a computer and detects as a trigger signal a state in which at least one of them is not being received. In response to the trigger signal being detected, power management signal output means gives an instruction to the power reduction means to perform the set mode.Type: GrantFiled: April 18, 2001Date of Patent: November 2, 2004Assignee: NEC-Mitsubishi Electric Visual Systems CorporationInventor: Hiroshi Otsuka
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Patent number: 6750619Abstract: 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 to a plurality of lamp filaments. Each secondary winding is connected to a lamp filament through a diode/capacitor combination with a current transformer primary located in a high frequency loop. A sensing circuit is connected to a current transformer secondary. A controller is connected to the sensing circuit and controls the filament power supply. Advantages include the ability to predict lamp end of life, detect disconnected filaments and other problems that appear as an open circuit such as loose or misinstalled lamps and prevent arcing, detect smoldering of a heavily carbonized lamp holder, or detect short circuits.Type: GrantFiled: October 4, 2002Date of Patent: June 15, 2004Assignee: Bruce Industries, Inc.Inventors: Arthur T. Nemirow, Storm S. Sears
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Patent number: 6603275Abstract: An electronic starter for fluorescent lamp has a preheating circuit for controlling the preheating of the fluorescent tube and a power switch and locking circuit for cutting off the current to the preheating circuit. The power switch and locking circuit makes use of the voltage level on the power input to determine the status of the fluorescent tube. A high voltage on the power input represents that the fluorescent tube has failed to turn on in the ignition operation, whereby the power switch and locking circuit thereupon cuts off the current to the preheat circuit, thereby eliminating flickering of the fluorescent tube and so preventing irritation to the eyes, and extending the service life of the lamp.Type: GrantFiled: June 5, 2001Date of Patent: August 5, 2003Inventor: Chen-Kuo Ku
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Patent number: 6552494Abstract: Herein described is a driver circuit of a fluorescent lamp having a first and a second electrode and igniting when the voltage between the first and second Electrode exceeds a given threshold voltage. The driver circuit comprises an inductance coupled to a supply voltage and to a terminal of the first electrode a first condenser coupled to the other terminal of the first electrode and to a terminal of the second electrode, a control device comprising a first and a second system of switches capable of guaranteeing oscillations of a voltage signal on the inductance and on the first condenser up to the ignition of the lamp. The driver circuit comprises a device associated to the control device and capable of acting on the first system of switches so as to regulate the frequency of the oscillations from a frequency greater than the resonance frequency of the inductance and of the first condenser to the same resonance frequency so as to guarantee a preheating of the first and second electrodes.Type: GrantFiled: January 31, 2002Date of Patent: April 22, 2003Assignee: STMicroelectronics s.r.l.Inventors: Vincenzo Randazzo, Atanasio La Barbera
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Patent number: 6504534Abstract: When a “screen saver” operates to display a homogeneous black picture image after the same image is continuously displayed on a CRT for a predetermined period of time, a power supply for a CRT display unit is controlled to be turned off, thereby preventing the CRT display unit from being left for a long time in a power-on state. Namely, a waiting time of 3 minutes, for example, is provided when the “screen saver” operates so that the CRT displays a homogeneous black picture image to turn off a power circuit for the CRT, and then a heater for the CRT is turned off after a lapse of a predetermined period of time of 5 to 60 minutes, for example. An extension graphics board, which is inserted in an open slot provided in a computer of an open architecture type may be provided to perform this function.Type: GrantFiled: May 2, 1996Date of Patent: January 7, 2003Assignee: Nanao CorporationInventors: Katsuhisa Takase, Yuichi Komatsu, Hajime Torii, Toshihisa Tanabe, Kazuhiro Konishi, Hideo Katada
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Patent number: 6495979Abstract: A power-saving apparatus comprises: a heater; a control unit for detecting at least two power-saving commands, and for outputting a first power-saving control signal and a second power-saving control signal; a power supply unit for supplying rated voltages required for peripheral devices; a power switching circuit for cutting off all rated voltages supplied to the peripheral devices, including the heater but excluding the control unit, when the first power-saving control signal is generated, and for starting the supply of all rated voltages cut off when the second power-saving control signal is generated; and a quick start circuit for supplying, to the heater, a quick start voltage for a certain time period when the start control signal is generated.Type: GrantFiled: January 2, 2001Date of Patent: December 17, 2002Assignee: SamSung Electronics Co., Ltd.Inventors: Kil-Soo Park, Jin-Sang Hwang, Kyung-Choon Youn
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Patent number: 6456009Abstract: An adaptive heater voltage algorithm and control system for setting and maintaining a vacuum electron device (VED) heater voltage, such as that of a klystron. An algorithm and control system are disclosed that sets and maintains the VED's cathode at the lowest temperature required for 98% of the beam current that corresponds to a fully space charge limited (FSCL) operation. VED lifetime is dependent upon cathode temperature, and in general, a cooler cathode will last longer. The optimum heater voltage corresponds to the beam current that is 98% of the beam current during FSCL operation. As the VED ages and the cathode becomes depleted, the heater voltage will need to be gradually increased to maintain the 98% FSCL value. There are, therefore, two stages to the adaptive heater voltage algorithm—(1) initial determination of the heater voltage and (2) the determination of the heater voltage during amplifier operation.Type: GrantFiled: July 31, 2000Date of Patent: September 24, 2002Assignee: Communication and Power IndustriesInventors: Edward L. Wright, Eric Oiesen
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Patent number: 6417630Abstract: A ballast circuit for operating a lamp having preheatable electrodes. The frequency of a high frequency bridge inverter is controlled by a control circuit which has input connections to one of the lamp electrodes for monitoring the electrode temperature. The voltage across the lamp electrode controls oscillation frequency during preheating and ignition.Type: GrantFiled: May 11, 2000Date of Patent: July 9, 2002Assignee: Koninklijke Philips Electronics N.V.Inventor: Bennie I. P. Simpelaar
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Patent number: 6404421Abstract: A heater circuit (H) according to the invention comprises a stabilizing power supply (SPS) with a control input (CT) which receives a control signal (Cs) to control the value at which the heater voltage (Vh) has to be stabilized. A timing circuit (TC) generates the control signal (Cs) such that the heater voltage (Vh) has a nominal value (Vhn) in a normal operation phase, and such that the heater voltage (Vh) has a boost value (Vhb) higher than the nominal value (Vhn) during a boost period (Tb) of a start-up phase (Ts). The normal operation phase is defined as the phase during which the heater (HE) is sufficiently hot to enable display of a picture with good quality. The start-up phase (Ts) is the phase during which the display apparatus starts up and the heater (HE) warms up.Type: GrantFiled: April 6, 1999Date of Patent: June 11, 2002Assignee: U.S. Philips CororationInventors: Robert R. Meijler, Edwin Van Eggelen, Patrick Louwyck
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Patent number: 6320319Abstract: A charged particle generating apparatus including a first electrode, a second electrode, a current source supplying a current to the first electrode for heating the first electrode and a voltage source for generating an attraction voltage for generation of an electric field between the first electrode and the second electrode. The first electrode discharges charged particles as a result of the generation of the electric field between the first electrode and the second electrode.Type: GrantFiled: December 16, 1999Date of Patent: November 20, 2001Assignee: Advantest CorporationInventors: Toshimichi Iwai, Takayuki Nakamura, Akira Kintaka
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Patent number: 6211620Abstract: A ballast for a fluorescent lamp includes a high frequency power source circuit for supplying a preheat start type fluorescent lamp with preheating and lighting current via an inductor. The high frequency power source circuit includes at least two switching elements for controlling application of voltages of different polarity to the fluorescent lamp, a self-exciting type switching element driving circuit for driving the switching elements so as to alternate on and off repeatedly; and a timer circuit for detecting lapse of a predetermined time from start of the ballast for the fluorescent lamp. The switching element driving circuit shortens an ON-period of at least one of the switching elements to restrict an increase of an amplitude of current flowing in the inductor during a period until the timer circuit detects lapse of a predetermined time.Type: GrantFiled: September 10, 1999Date of Patent: April 3, 2001Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Masayoshi Gyoten, Masataka Ozawa, Masanobu Murakami, Koji Miyazaki
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Patent number: 6114810Abstract: An electronic ballast circuit for fluorescent lamps, said circuit comprises an anti-interfering circuit, a rectifying circuit, a filtering circuit, a frequency-converting circuit and a resonant circuit connected sequentially; a main resonant capacitor C4 is connected between the end of the the fluorescent lamp connected with the resonant inductor L1 in the resonant circuit and the negative end of the filtering circuit, so that resonant inductor L1 and main resonant capacitor C4 constitute a main resonant circuit; the Q factor of the main resonant circuit is not affected by the resistance of the filaments at both ends of the fluorescent lamp, so that the voltage applied across both ends of the lamp can be raised; and a preheating circuit is provided between both two ends of the main resonant capacitor, so that the filaments of the lamp can be preheated before the lamp is started.Type: GrantFiled: April 22, 1998Date of Patent: September 5, 2000Assignee: Mass Technology (H.K.) Ltd.Inventor: Onn Fah Foo
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Patent number: 6091187Abstract: Direct and indirect electron bombardment provide a sufficiently high degree of temperature uniformity across the emitting surface of a large-area electron source for an electron beam projection system such that a broad beam having illumination uniformity within 1% can be achieved. A diode gun is used to obtain extraction field uniformity and maintain uniformity of illumination. Power requirements and power dissipation in beam periphery truncating apertures is reduced by roughening the surface of a monocrystalline cathode or depositing materials having a higher work function thereon.Type: GrantFiled: April 8, 1998Date of Patent: July 18, 2000Assignee: International Business Machines CorporationInventors: Steven D. Golladay, Rodney A. Kendall, Carl E. Bohnenkamp
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Patent number: 6084355Abstract: A cathode heater of a cathode ray tube is rapidly energized either when turning on electric power or when returning to a power-on state mode of the Display Power Management System (DPMS) in an electronic appliance using the cathode ray tube as a video display device. A high voltage generation unit is provided for generating a voltage higher than a rated voltage of the cathode heater of the cathode ray tube. The cathode ray tube enables a stable video display to be presented in a shorter time period due to a rapid heating of the cathode caused when an initial heating unit applies a voltage to the cathode heater which is higher than the rated voltage of the cathode heater, according to a pulse signal which exists for a predetermined time period when turning on electric power or when returning to a power-on state mode of the DPMS.Type: GrantFiled: December 15, 1997Date of Patent: July 4, 2000Assignee: SamSung Electronics Co., Ltd.Inventor: Tae Jin Park
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Patent number: 6008587Abstract: An electronic ballast control apparatus and method for fluorescent lamps includes applying a heating current through the filaments of the lamp, and delaying the application of arc current through the filaments and the gas for a predetermined time. This allows the filaments to heat up to a level capable of sustaining thermionic emission, thereby eliminating sputtering damage upon the application of the arc current.Type: GrantFiled: February 29, 1996Date of Patent: December 28, 1999Inventor: Robert Mills