Discharge Control Discharge Device Load Patents (Class 315/237)
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Patent number: 8294390Abstract: In a discharge lamp lighting apparatus, in a starting sequence of a discharge lamp, while a frequency control circuit generates a inverter driving signal corresponding to resonance frequency of a resonant circuit, a power supply circuit outputs non-load open circuit voltage that is sufficient to maintain electric discharge, even when a boosting action accompanying a resonance phenomena disappears, and then a periodic drive circuit generates the inverter driving signal to gradually decrease frequency of the inverter from a frequency corresponding to the resonance frequency of the resonant circuit, until the frequency of the inverter reaches a first threshold frequency, and wherein when the frequency of the inverter reaches the first threshold frequency, while the periodic drive circuit generates the inverter driving signal so that the frequency of the inverter turns into a stable lighting frequency, the power supply circuit outputs current that is sufficient to maintain the electric discharge of the dischargeType: GrantFiled: July 27, 2010Date of Patent: October 23, 2012Assignee: Ushio Denki Kabushiki KaishaInventors: Takanori Samejima, Masashi Okamoto
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Publication number: 20090123143Abstract: An image taking system includes an image taking circuit which photographs the object upon receipt of a photographing instruction and obtains an image representing the object, a light emitting circuit which emits stroboscopic light, a photographing control circuit which controls the image taking circuit to execute a continuous photographing where a plurality of images are continuously taken including a plurality of images with following stroboscopic light, a stroboscopic light control circuit which controls the light emitting circuit to emit the stroboscopic light when photographing the images with following stroboscopic light, and an estimating circuit which estimates, when photographing the images with following stroboscopic light, the remaining energy in the charging unit after the photographing, on the basis of each light emission and the remaining energy in the charging unit upon the light emission.Type: ApplicationFiled: November 7, 2008Publication date: May 14, 2009Applicant: FUJIFILM CorporationInventor: Kazunori TAMURA
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Patent number: 6856101Abstract: Switching of parallel capacitors in an HID bi-level lighting control system is accomplished through use of transient voltage suppression across an electronic relay for discharge of residual charge from a switched capacitor when combined peak voltage exceeds clamping voltage, thereby allowing maximum switch voltage rating to be lower than is possible through the use of conventional switching methods and circuitry. The invention contemplates method and apparatus permitting capacitive switching at voltage levels higher than are possible in conventional capacitive switching arrangements including capacitive switching arrangements used in lighting control systems.Type: GrantFiled: July 24, 2002Date of Patent: February 15, 2005Assignee: Acuity Brands, Inc.Inventor: William Henry Hitchcock
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Patent number: 6593704Abstract: The invention relates to a method and a ballast for feeding a UV light low pressure radiator. The UV light low pressure radiator is ignited and subsequently fed with direct current. The polarity of the direct current is changed at successive intervals which are greater than half the period of the conventional network frequency and smaller than a time until a lower threshold value for the operational temperature of the electrodes is reached, whereby said time is a result of the thermal time constant of the UV light low pressure radiator.Type: GrantFiled: December 4, 2001Date of Patent: July 15, 2003Assignee: Wedeco AG Water TechnologyInventors: Dirk Riepe, Jan Rudkowski
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Patent number: 6274986Abstract: An apparatus and method for applying short pulsed waveforms, on the order of 1 &mgr;s pulses at a frequency of about 5 kHz, to a discharge lamp, such as a low-pressure mercury/argon lamp, in order to shift the ratio of the intensities of two of the mercury lines, in particular the 254 nm and 365 nm lines, of which for a sinusoidal excitation signal the 254 nm line is predominant, towards the higher wavelength. This greatly increases the efficiency of a lamp using phosphors excited by these UV emissions, because of the reduced Stokes shift.Type: GrantFiled: April 3, 2000Date of Patent: August 14, 2001Assignee: University of SheffieldInventors: Robin Devonshire, Timothy James Healey, David Andrew Stone, Richard Charles Tozer
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Patent number: 6150761Abstract: A ballast for a compact fluorescent lamp includes a down-converter for operating the lamp with a DC current during stable operation and a charge pump for igniting the lamp. The converter includes an inductor and a first series circuit of a first diodie and a first switching element. An output capacitor shunts the lap terminals. The charge pump includes a second series circuit of second diodie and a second switching element coupled to the lamp terminals with the second diode polarized to prevent the discharge of the output capacitor when the second switching element is conductive. The inductor cooperates with the first and second diodes and the second switching element to build up the voltage across the outpout capacitor to the ignition voltage level of the lamp.Type: GrantFiled: September 21, 1999Date of Patent: November 21, 2000Assignee: U.S. Philips CorporationInventors: Etienne N. K. P. M. Eberson, Antonius A. M. Marinus
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Patent number: 5838115Abstract: In a gas discharge device having a gas discharge channel, which comprises two gas discharge electrodes and a gas discharge volume lying between said electrodes, having an energy storage circuit connected by a switching device to the gas discharge electrodes for producing a current surge flowing between a first output terminal and a second output terminal for operating a gas discharge, and having an ignition device for separate ignition of the gas discharge, in order to improve said device in such a way that it operates better and more reliably, it is proposed that the switching device comprises a voltage divider lying between the output terminals and comprising a first and a second impedance, that the gas discharge electrodes are connected in parallel to the first impedance and a spark gap is connected in parallel to the second impedance, that the first impedance is so dimensioned that, in the absence of a gas discharge, a voltage lying below the breakdown voltage of the gas discharge electrodes is applied toType: GrantFiled: March 25, 1997Date of Patent: November 17, 1998Assignee: Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V.Inventors: Markus Jung, Eberhard Zeyfang, Guenther Renz
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Patent number: 5592052Abstract: A fluorescent lamp (2) having at least two phosphor coatings (12) on the surface of the sealed lamp bulb, typically an inner surface. There is variable driving means which preferentially activates one phosphor and not the other phosphors, at one arrangement or setting or configuration of the driving means, while at another setting the driving means activates in addition a different or several different phosphors. Each phosphors may be a blend of phosphors and the phosphors and/or blends may be overcoated upon one another forming multiple layers or all mixed together and applied as a one layer coating on the lamp surface.Type: GrantFiled: June 13, 1995Date of Patent: January 7, 1997Assignee: Matsushita Electric Works R&D LaboratoryInventors: Jakob Maya, Jagannathan Ravi
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Patent number: 4613797Abstract: A flash strobe power supply adapted for controlling alternately the energization of a pair of flash lamps includes a trigger timing device for generating a series of positive pulses and a series of negative pulses spaced in time from the positive pulses by a predetermined interval. First and second energy storage devices are provided for repeatedly charging incrementally during successive charging cycles and for storing a charge to be applied to respective first and second flash lamps. An inverter oscillator circuit includes a pulse width modulator and a transformer for generating a quasi-squarewave signal whose frequency is greater than the frequency of the positive and negative pulses to control the incremental charging of the energy storage devices. First and second switching devices deliver when conductive the charge stored in the first and second energy storage devices to their respective first and second flash lamps.Type: GrantFiled: July 27, 1984Date of Patent: September 23, 1986Assignee: Federal Signal CorporationInventors: Frederick W. Eggers, Paul D. Graham, Bruce E. Heeb
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Patent number: 4398129Abstract: A flashlamp drive circuit 10 using an unsaturated transistor Q1 as a current mode switch to periodically subject a partially ionized gaseous laser excitation flashlamp 20 to a stable, rectangular pulse of current from an incomplete discharge of an energy storage capacitor C1. A monostable multivibrator MV1 sets the pulse interval, initiating the pulse in response to a flash command by providing a reference voltage to a non-inverting terminal of a base drive amplifier AV1; a tap on an emitter resistor R2 provides a feedback signal sensitive to the current amplitude to an inverting terminal of amplifier AV1, thereby controlling the pulse amplitude. The circuit drives flashlamp 20 to provide a square-wave current flashlamp discharge.Type: GrantFiled: June 24, 1981Date of Patent: August 9, 1983Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventor: Kenyon E. Logan
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Patent number: 4335297Abstract: An electron beam processor with an energy storage line and matched field emission diode that define a high energy electron beam generator. A transport system positions a specimen to be thermally processed in a processing station. Energy stored on the line is discharged through the diode and the resulting high energy beam impacts upon the specimen for thermally processing selected regions thereof.Type: GrantFiled: December 19, 1980Date of Patent: June 15, 1982Assignee: Spire CorporationInventor: Roger G. Little