Condenser In Shunt To The Load Device And The Supply Patents (Class 315/241R)
  • Patent number: 6144174
    Abstract: To control low-pressure fluorescent lamps, there is provided a device comprising a first change-over switch circuit and a second change-over switch circuit, respectively including a first power transistor and a second power transistor. The first change-over switch circuit first of all measures the period of time when the second power transistor is on. Then, secondly, it turns the first power transistor on for a period equal to the period measured.
    Type: Grant
    Filed: January 15, 1997
    Date of Patent: November 7, 2000
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventor: Marco Bildgen
  • Patent number: 6118222
    Abstract: A circuit for complementing the AC mains supply voltage, particularly for resistive loads, comprising a rectifier inserted between an AC power source and a resistive load and adapted to prevent the reverse flow of a processed portion of the AC supply voltage towards the AC power source, and one or more capacitors arranged ahead of the resistive load; the circuit has the particularity that the values of the one or more capacitors are chosen, according to table 2, low enough to maintain the AC nature of the AC voltage and to complement, during discharge towards the resistive load, the AC supply voltage until a desired value thereof is reached.
    Type: Grant
    Filed: April 5, 1999
    Date of Patent: September 12, 2000
    Inventors: Lucio Falace, Rosario Tortora
  • Patent number: 6104144
    Abstract: A conventional stroboscope circuit in use for a film camera has encountered with problems that charging of a main capacitor is incapable when other functions of the camera are operated and that a charging operation is delayed. To solve aforesaid problems, the present invention is to charge the capacitor C1 for a flashlight illumination by a use of a stroboscope charging circuit 1. During that, a usual charging operation is performed by feeding a higher current which flows through a transistor Q1, in a manner wherein a control signal CTL is switched to an H (a high) level status. When the other functions of the camera are operated on the contrary, the charging is performed by feeding a lower current which flows through a resistor R1, wherein the control signal CTL is switched to an L (a low) level status.
    Type: Grant
    Filed: March 2, 1998
    Date of Patent: August 15, 2000
    Assignee: Stanley Electric Co., Ltd.
    Inventors: Takayuki Yoneya, Keizo Sekido
  • Patent number: 6078145
    Abstract: An apparatus for simply retrofitting pre-existing vehicular incandescent hazard flashing lamps or strobe assemblies having high voltage wiring with low voltage, low-cost, two wire synchronized strobe lamp assemblies without requiring the altering of the vehicle's existing structure or wiring. The apparatus utilizes a high voltage d.c. to d.c. converter circuit which may be completely contained within the lamp housing so that no high voltage wiring will be routed through the vehicle. The strobe trigger circuit operates by sensing the ground potential at its input to trigger the strobe assembly's flash tube. This feature allows the synchronization of all circuit lamps, both incandescent and strobe, on a two wire flasher circuit without the need for a third wire to provide the trigger signal to the flash circuit. One embodiment of the invention works autosynchronously in conjunction with a standard electromechanical flasher relay as may be utilized in a typical vehicular warning light system.
    Type: Grant
    Filed: December 9, 1997
    Date of Patent: June 20, 2000
    Assignee: Weldon Technologies, Inc.
    Inventors: Sean P. Tillinghast, Robert J. Knauff
  • Patent number: 6066925
    Abstract: The peak voltage of a periodic capacitive discharge, applied across first and second electrodes of the incandescent lamp, is about equal to the nominal DC voltage of the lamp multiplied by 3.2. The repetition rate of discharging, the extent of charging and discharging, and the value of the capacitance producing the periodic discharge result in the values of momentary peak and nominal temperature of the filament of the lamp being equal. Thereby, the value of peak luminous flux emission with respect to the nominal luminous flux emission of the lamp is several times greater. Where the discharge is periodic at a rate equal to about 14. HZ, then luminous flux emission by the lamp appears to the human eye to be continuously bright at an intensity equal to the peak value of luminous flux emission of the lamp, and the emission of the lamp is suitable for providing illumination. Emission of the lamp is suitable for providing emergency flashing where the discharge is periodic at a rate equal to about 1. HZ.
    Type: Grant
    Filed: July 14, 1997
    Date of Patent: May 23, 2000
    Inventor: Peter H. Lehmann
  • Patent number: 6064159
    Abstract: In a power-saving stroboscopic device, a main capacitor is not completely discharged even in full light emission, so that a predetermined amount of charge can be left in a main capacitor, in order to save power in a stroboscopic circuit of the device. A light emission unit of the stroboscopic device can perform full light emission and flat emission based on a period of light emission time set by predetermined conditions. The stroboscopic device comprises a light emission control unit and a control unit for controlling a period of light emission time, so that a residual voltage in a main capacitor in the stroboscopic circuit is higher than a residual voltage after full light emission, in order to improve the charging efficiency after the full light emission.
    Type: Grant
    Filed: October 29, 1996
    Date of Patent: May 16, 2000
    Assignee: Olympus Optical Co., Ltd.
    Inventors: Hiroshi Yamada, Akira Inoue
  • Patent number: 6034486
    Abstract: The present invention relates to an electronic flash device which, even if the charged voltage of a main capacitor is low, can securely effect a trigger operation by making a trigger voltage higher than the charged voltage of the main capacitor.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: March 7, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hajime Fukui
  • Patent number: 6011359
    Abstract: The present invention discloses a multiple flash/single lamp circuit for fast sequential strobing. More particularly, the present invention comprises a flashlamp, a pair of capacitors, a voltage multiplier and regulator to charge the capacitors, a pair of trigger circuits to discharge the capacitors and a controller to selectively activate each trigger circuit to activate the flashlamp.
    Type: Grant
    Filed: January 16, 1998
    Date of Patent: January 4, 2000
    Assignee: Acushnet Company
    Inventor: Charles A. Days
  • Patent number: 5949196
    Abstract: An arrangement for switchably operating one or more gas discharge lamps, such a compact or circline fluorescent lamps, with a single ballast commonly used with a linear fluorescent lamp. One or more capacitors is either in parallel or in series with the gas discharge lamp. When engaged by a switch, the capacitor either shunts or reduces the current to the gas discharge lamp in a manner which allows appropriate starting voltage, appropriate operating current and a plurality of illumination levels of the gas discharge lamp.
    Type: Grant
    Filed: March 13, 1997
    Date of Patent: September 7, 1999
    Assignee: Lumatech Corporation
    Inventors: Ronald A. Lesea, Bruce A. Pelton
  • Patent number: 5903109
    Abstract: An electrodeless low-pressure discharge lamp according to the invention has a lamp vessel (1) which is closed in a gastight manner, which contains an ionizable filling, and which has a cavity (10). In the cavity (10) an elongate coil (2) is positioned with a primary and a secondary winding (21, 22, respectively) of an electrical conductor (20) around a coil former (3) which has a tip (30) which points into the cavity (10). The electrical conductor (20) from which the secondary winding (22) is formed extends from a first end (22a) of the secondary winding (22) facing the tip (30) into a recess (32) of the tip (30) of the coil former (3) and is clamped therein. The first end (22a) of the secondary winding (22) can be easily fastened in this manner.
    Type: Grant
    Filed: April 18, 1997
    Date of Patent: May 11, 1999
    Assignee: U.S. Philips Corporation
    Inventors: Nicasius G.T. Van Gennip, Petrus J.M. Fransen, Winand H.A.M. Friederichs, Petrus H. Antonis
  • Patent number: 5894202
    Abstract: An ignition device for gas discharge lamps is proposed, in particular for motor vehicle lights. The ignition device contains a first transformer (17) which is supplied on its primary side with an alternating current produced from a direct current supply voltage. To generate this alternating current, a capacitor (14), which is acted upon by a charging current, constitutes a closed circuit together with the primary winding of the first transformer and a spark gap (16), wherein the spark gap (16) arcs at a predetermined charge state of the capacitor (14). This device makes a simple, inexpensive, and space-saving device possible for generating the required operating voltage for the transformer (17), wherein the spark gap can be reliably used, even at higher temperatures.
    Type: Grant
    Filed: January 3, 1997
    Date of Patent: April 13, 1999
    Assignee: Robert Bosch GmbH
    Inventors: Dieter Betz, Ulrich Drews, Thomas Gross, Bernd Rothfuss, Thomas Kienzler
  • Patent number: 5869936
    Abstract: A strobe device according to the present invention includes: a main capacitor; and step-up means including at least one step-up capacitor, the at least one step-up capacitor being rapidly charged via a flash discharge tube in an ionization state, a charged voltage of the at least one step-up capacitor being superimposed on a charged voltage of the main capacitor and applied across the flash discharge tube at least via an insulated gate bipolar transistor and a restriction resistor coupled in series with the flash discharge tube.
    Type: Grant
    Filed: July 29, 1997
    Date of Patent: February 9, 1999
    Assignee: West Electric Company, Ltd.
    Inventors: Katsumi Horinishi, Takanaru Kobayashi
  • Patent number: 5838115
    Abstract: 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 to
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: November 17, 1998
    Assignee: Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V.
    Inventors: Markus Jung, Eberhard Zeyfang, Guenther Renz
  • Patent number: 5814948
    Abstract: A flash circuit for a low cost camera in which a voltage dependent resistor is employed as a flash capacitor charge voltage sensing device to perform a control effect in the flash circuit, such as turning on a flash ready indicator light or activating a oscillation terminating device to arrest self oscillations in a flash charging circuit.
    Type: Grant
    Filed: January 14, 1997
    Date of Patent: September 29, 1998
    Assignee: Eastman Kodak Company
    Inventor: Paul Teremy
  • Patent number: 5736819
    Abstract: Power to a self-oscillating inverter ballast is supplied from a DC voltage source through an inductor means having two separate windings on a common magnetic core--with one winding being positioned in each leg of the power supply. The inverter is loaded by way of a parallel-tuned L-C circuit connected across the inverter's output, thereby providing an output voltage thereat. The output voltage consists of sinusoidally-shaped voltage pulses of alternating polarity, with a distinct brief period of discontinuity at or near the cross-over points. A fluorescent lamp is connected by way of a current-limiting capacitor with the inverter's output.
    Type: Grant
    Filed: March 14, 1995
    Date of Patent: April 7, 1998
    Inventor: Ole K. Nilssen
  • Patent number: 5661372
    Abstract: A stroboscopic instrument is constructed of a gate-controlled switching element forming a discharge loop that is connected in series with a discharge lamp and main capacitor for storing charge that causes the discharge lamp to flash. The stroboscopic instrument further comprises: a stroboscopic flashing control circuit for controlling the operation of stroboscopic flashing; a low-voltage power supply that has an output voltage lower than the driving voltages of the stroboscopic flashing control circuit and the gate-controlled switching element; a first constant voltage regulator for stepping up the voltage of the low-voltage power supply up to the driving voltage of the stroboscopic flashing control circuit; and a second constant voltage regulator for stepping up the voltage of the low-voltage power supply or the output voltage of the first constant voltage regulator up to the driving voltage of the gate-controlled switching element.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: August 26, 1997
    Assignee: Olympus Optical Co., Ltd.
    Inventors: Toshiaki Ishimaru, Hiroshi Yamada
  • Patent number: 5606222
    Abstract: A lighting system having a gas discharge lamp and a stabilization ballast further includes a low loss device to reduce the current through the ballast and lamp, thereby reducing system wattage for energy savings. For a lead-type ballast, the current reducing device is a capacitive device in parallel with the discharge lamp. For a lag-type ballast, the device is an inductive device in parallel with the lamp. The device may be in a housing connected between the lamp ballast and the lamp, or may be included within the outer envelope of the discharge lamp. This enables an existing system to be easily retrofit without disturbing the existing ballast.
    Type: Grant
    Filed: December 29, 1994
    Date of Patent: February 25, 1997
    Assignee: Philips Electronics North America Corporation
    Inventors: Eduardus J. Cottaar, Dirk Van Pijkeren
  • Patent number: 5602446
    Abstract: A fast repetition rate (FRR) flasher suitable for high flash photolysis including kinetic chemical and biological analysis. The flasher includes a power supply, a discharge capacitor operably connected to be charged by the power supply, and a flash lamp for producing a series of flashes in response to discharge of the discharge capacitor. A triggering circuit operably connected to the flash lamp initially ionizes the flash lamp. A current switch is operably connected between the flash lamp and the discharge capacitor. The current switch has at least one insulated gate bipolar transistor for switching current that is operable to initiate a controllable discharge of the discharge capacitor through the flash lamp. Control means connected to the current switch for controlling the rate of discharge of the discharge capacitor thereby to effectively keep the flash lamp in an ionized state between Successive discharges of the discharge capacitor.
    Type: Grant
    Filed: March 23, 1995
    Date of Patent: February 11, 1997
    Assignee: Associated Universities, Inc.
    Inventors: Zbigniew Kolber, Paul Falkowski
  • Patent number: 5585700
    Abstract: An electronic ballast for one or more F32T8 or F25T8 or F17T8 fluorescent lamps has a new design tool for efficient transfer of power to the lamp or the lamps. The design tool is constructed from the ballast DC voltage and the commercially available lamp specifications by the manufacturers or from the American National Standards (ANSI). This design tool is shown below: Frequency.times.Capacitance=CONSTANT. ##EQU1## where W=Lamp rating in watts, V.sub.0 =Lamp voltage.V.sub.1 =Electronic Ballast DC voltage,R.sub.0 =Lamp Impedance in ohms,(ANSI C78.1-1991).k=Empirical constant=2.5 to 3.5.
    Type: Grant
    Filed: February 13, 1995
    Date of Patent: December 17, 1996
    Assignee: Power Electronics & Systems, Inc.
    Inventor: Zahir M. Ahmed
  • Patent number: 5574337
    Abstract: An electronic flash device including a self-oscillating charging circuit, a momentary trigger for initiating oscillations of the circuit to charge a flash capacitor, and a voltage sensing device coupled directly between the circuit and the flash capacitor for arresting the oscillations when the capacitor is fully charged. The voltage sensor includes a zener diode in series with a neon ready-light, and switches on a transistor to ground the charging circuit and arrest the oscillations when the capacitor is fully charged. Actuation of the flash device automatically restarts the oscillations and recharges the flash capacitor. A process for recycling a single use camera having such an electronic flash device also is disclosed.
    Type: Grant
    Filed: October 28, 1994
    Date of Patent: November 12, 1996
    Assignee: Eastman Kodak Company
    Inventor: Clay A. Dunsmore
  • Patent number: 5570077
    Abstract: A drive circuit for use with an ambient condition detector limits heat dissipation and associated temperature rises in the presence of varying RMS values of an applied AC signal. The drive circuit includes a voltage doubler with a current regulator located between first and second storage elements. In the presence of a sensed ambient condition, which exceeds a predetermined threshold the regulator is enabled permitting one of the storage elements to be charged to a voltage on the order of twice the peak value of the applied AC voltage. A digital timer is used to trigger a flashable visual indicator from the stored DC voltage. The regulator provides a substantially constant DC voltage to the visual indicator in the presence of a varying AC line voltage.
    Type: Grant
    Filed: April 21, 1995
    Date of Patent: October 29, 1996
    Assignee: BRK Brands, Inc.
    Inventor: Michael A. Swieboda
  • Patent number: 5543690
    Abstract: The invention relates to a circuit arrangement for operating a discharge lamp. According to the invention the series connection of a PTC thermistor V1 with a bi-directionally acting breakdown voltage component V2 is disposed parallel to the inductance L1 and/or the capacitor C1 in a load circuit which has a discharge lamp H1, an inductance L1 connected in series with the discharge lamp and a capacitor C1 disposed parallel to the discharge lamp H1, wherein the PTC thermistor V1 and the bi-directionally acting breakdown voltage component V2 are thermally coupled. The object of the invention is to provide a simple circuit arrangement for operating a discharge lamp which allows a substantially constant ignition of a discharge lamp.
    Type: Grant
    Filed: February 18, 1994
    Date of Patent: August 6, 1996
    Assignee: Prolux Maschinenbau GmbH
    Inventors: Erhard Bernicke, Klaus Rohr, Karl Eibisch
  • Patent number: 5532555
    Abstract: An electronic flash apparatus having a main capacitor for storing charges, a discharge light emitting tube for emitting light in accordance with the charges stored in the main capacitor, a CPU for performing camera sequence control, and an IGBT coupled to each of the discharge light emitting tube and the CPU. The CPU includes a light emission control terminal for controlling a light emission timing of the discharge light emitting tube and the CPU is supplied with a CPU operation voltage. The IGBT includes a gate terminal connected to the light emission control terminal of the CPU, a collector terminal, and an emitter terminal, wherein, responsive to the light emission control terminal inputting to the gate terminal a control voltage substantially equivalent to the CPU operation voltage, a channel is formed between the collector terminal and the emitter terminal and the charges of the main capacitor are discharged through the discharge light emitting tube.
    Type: Grant
    Filed: February 21, 1995
    Date of Patent: July 2, 1996
    Assignee: Olympus Optical Co., Ltd.
    Inventor: Hiroshi Yamada
  • Patent number: 5532553
    Abstract: The light output of an electroluminescent panel is increased by using resonant transformation to increase the operating voltage across the panel to a level greater than the source or input voltage. This is accomplished by connecting the electroluminescent panel into a series resonant circuit whose capacitance value is made up at least in part of the intrinsic capacitance of the electroluminescent panel itself, and by choosing the inductance and capacitance values of the series resonant circuit to produce the desired output voltage across the electroluminescent panel. The resulting circuit is simple and low in cost, does not significantly add to the operating losses of the system, and takes advantage of the intrinsic capacitance of the panel in providing the desired resonant transformation.
    Type: Grant
    Filed: October 19, 1994
    Date of Patent: July 2, 1996
    Assignee: Hubbell Incorporated
    Inventor: Isaac L. Flory, IV
  • Patent number: 5523654
    Abstract: This circuit facilitates the triggerability of a remote three wire flashtube and trigger coil assembly at a much lower than normal anode power supply voltage. The discharge of the trigger capacitor produces the usual trigger-event in the trigger coil. Simultaneously, a trigger boost capacitor boosts the flashtube anode voltage to approximate the supply voltage plus the voltage across the trigger coil primary winding. As a result, the flashtube anode voltage is essentially doubled at the outset of each trigger event.
    Type: Grant
    Filed: June 16, 1994
    Date of Patent: June 4, 1996
    Assignee: Tomar Electronics, Inc.
    Inventors: Thomas R. Sikora, Richard J. Garling
  • Patent number: 5519287
    Abstract: A two terminal pulse width modulated incandescent lamp dimmer using low frequency pulse repetition rate provides increased illuminating efficiency by compensating both for light producing inefficiency of a tungsten filament at dimmed level settings, and for internal resistance of a direct current power source. A preferred embodiment of the dimmer is designed for 3.5 to 9.0 volt operation.
    Type: Grant
    Filed: March 21, 1994
    Date of Patent: May 21, 1996
    Inventors: Garold J. Goodale, Jr., Herbert W. Behlow, Jr., David E. Wilson
  • Patent number: 5512801
    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.
    Type: Grant
    Filed: August 18, 1994
    Date of Patent: April 30, 1996
    Inventor: Ole K. Nilssen
  • Patent number: 5493181
    Abstract: An electronic ballast includes a boost circuit, a low voltage control circuit, and a driven inverter in a half-bridge, push-pull, series resonant, parallel loaded configuration. The boost circuit includes a low voltage output for powering the control circuit. In the event of a fault, the control circuit shuts off the boost circuit and the inverter. A sense capacitor is in series with the lamps and the voltage across the capacitor prevents a timer in the control circuit from shutting off the ballast. The timer circuit waits a period longer than the time it takes for the lamps to start normally. The sense capacitor is either in series with the lamp across the resonant capacitor or is in series with the resonant capacitor.
    Type: Grant
    Filed: May 8, 1995
    Date of Patent: February 20, 1996
    Assignee: Energy Savings, Inc.
    Inventors: Peter W. Shackle, Randy G. Russell, Kent E. Crouse
  • Patent number: 5396152
    Abstract: The Lamp (La) is connected in series with first reactive impedances (C1, . To generate pulses, one or more second reactive impedances (C3, L3; C3-L2) are located as energy storage elements in series with one or more switch elements (S3, VTh1, VD1) to at least one of the first reactive impedances (C1, L1) and also in series with the high-pressure gas discharge lamp.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: March 7, 1995
    Assignee: Patent-Treuhand-Gesellschaft fur Elektrische Gluhlampen m.b.H.
    Inventor: Michael Bonigk
  • Patent number: 5387845
    Abstract: A power-line-operated frequency-converting power supply provides a 30 kHz current-limited AC voltage at an output receptacle. A neon lamp is connected across the secondary winding of a gapped ferrite-type leakage transformer, the primary winding of which is connected with the output receptacle by way of a light-weight cord, thereby permitting the lamp-transformer combination to be located remotely from the power supply. The secondary winding is arranged to have a well defined inductance; which inductance is tuned to resonate at 30 Khz by way of a parallel-connected tuning capacitor. Tightly coupled with the secondary winding is a control winding with which is connected a protection circuit operative to place an auxiliary capacitor across the control winding in case the neon lamp fails to ignite within a few milli-seconds, thereby detuning the secondary winding enough to protect the power supply and the leakage transformer from sustained overload.
    Type: Grant
    Filed: May 26, 1992
    Date of Patent: February 7, 1995
    Inventor: Ole K. Nilssen
  • Patent number: 5384518
    Abstract: A power source device includes a voltage converting means to input side of which a DC voltage source is connected and to output side of which a capacitance element and a load circuit are connected, while a control circuit is connected to the voltage converting means and the load circuit, the latter circuit having a load impedance made lower upon starting of a load in the load circuit than that in stable lighting of the load, wherein such control constant as oscillation frequency and duty are made to be substantially constant at the time of the starting and stable lighting of the load, and a switching means in the voltage converting means is turned OFF when the capacitance element has a voltage below a predetermined value.
    Type: Grant
    Filed: June 9, 1994
    Date of Patent: January 24, 1995
    Assignee: Matsushita Electric Works, Ltd.
    Inventors: Shojiro Kido, Toshiaki Nakamura, Takashi Kambara, Yoshitaka Taga, Haruo Nagase
  • Patent number: 5382882
    Abstract: A power supply circuit for a gas discharge lamp is disclosed. The power supply circuit includes a circuit for providing a d.c. bus voltage on a bus conductor, and a resonant lamp circuit. The resonant lamp circuit includes a gas discharge lamp, a first resonant impedance in series with the gas discharge lamp, and a second resonant impedance substantially in parallel with the gas discharge lamp. The resonant load circuit operates at a resonant frequency determined by the values of the first and second resonant impedances. Further included is a series half-bridge converter for impressing across the resonant load circuit a bidirectional voltage, and thereby inducing a bidirectional current in the resonant load circuit.
    Type: Grant
    Filed: April 20, 1993
    Date of Patent: January 17, 1995
    Assignee: General Electric Company
    Inventor: Louis R. Nerone
  • Patent number: 5343125
    Abstract: To ensure ignition of a high-pressure discharge lamp, for example a metal vapor halogen high-pressure dicharge lamp which has an ignition circuit, and is operated by direct current from an inverter circuit controlled for pulse width modulation, current flow to the lamp is extended in time upon initial energization thereof so that an initial hot spot which forms on an electrode can remain hot to establish a stabilized arc. This extension of current flow can be obtained by an R/C circuit in parallel to the output or storage capacitor (C.sub.A) of the inverter circuit (FIG. 1) or by an NTC resistor (H) in series with the lamp, or by a resistor which is short-circuited by a relay contact as the lamp operates, or the like.
    Type: Grant
    Filed: November 1, 1991
    Date of Patent: August 30, 1994
    Assignee: Patent-Treuhand-Gesellschaft feur elektrische Gluehlampen mbH
    Inventors: Franz Bernitz, Andreas Huber, Frank Hansmann
  • Patent number: 5338110
    Abstract: A circuit for lighting a fluorescent lamp. The present invention takes into account the fastidious characteristics of the fluorescent lamp, and during the momentary lighting of the fluorescent lamp. In order to reduce the temperature fluctuations, a separate pre-heating power is supplied. The circuit includes: a first resonance circuit consisting of a first capacitor connected to the opposite ends of the fluorescent lamp, a resonance inductor, a second capacitor, a first switch and a DC power source, serially connected; a second resonance circuit consisting of a second switch, a first capacitor, a resonance inductor, a third capacitor and a DC power source, serially connected; a switch control circuit for activating the first and second switches in an alternate manner. Before the lighting of the fluorescent lamp, the first and second resonance circuits are put to a resonance state, while, after the lighting of the fluorescent lamp, the resonance is eliminated.
    Type: Grant
    Filed: April 21, 1993
    Date of Patent: August 16, 1994
    Assignee: Seon Woong Koh
    Inventor: Jae H. Byun
  • Patent number: 5334915
    Abstract: An operating circuit arrangement for a discharge lamp has a chopper circuit and an inverter circuit. The inverter circuit generates a high frequency voltage to start and operate the discharge lamp. The chopper circuit supplies a d.c. voltage to the inverter circuit. The circuit arrangement has a chopper control circuit and an inverter control circuit which are coupled to the chopper circuit so that the operation of each control circuit responds to the chopper circuit. In order to perform a soft starting operation in which the inverter circuit generates a given high frequency voltage to start and operate the discharge lamp prior to the generation of a given level of d.c. voltage generated by said chopper circuit, an inverter control circuit coupled to the inverter circuit is provided.
    Type: Grant
    Filed: September 30, 1992
    Date of Patent: August 2, 1994
    Assignee: Toshiba Lighting & Technology Corporation
    Inventors: Hajime Ohsaki, Keiichi Shimizu
  • Patent number: 5331254
    Abstract: A starting circuit for an electrodeless HID lamp includes a visible light radiator for illuminating a gas probe starter during lamp starting. In one embodiment, a light emitting diode (LED) illuminates the gas probe starter via a quartz tube. Excitation is provided to the LED by the same source used to excite the gas probe starter.
    Type: Grant
    Filed: January 19, 1993
    Date of Patent: July 19, 1994
    Assignee: General Electric Company
    Inventors: John P. Cocoma, George A. Farrall
  • Patent number: 5317237
    Abstract: A low voltage DC input ballast circuit for a discharge lamp particularly suitable for a central lighting system includes an input filter stage which feeds into a first boost converter circuit controlled by way of a pulse width modulator device. The first boost converter provides warm-up and steady state run signals to the lamp in a voltage fed manner over a coupling circuit using components which are reduced in size relative to conventional discharge ballast circuits. Control circuitry provides various monitoring functions, an example of which is that, in the event of a low input voltage, the lamp will operate in a dimmed or faded manner rather than maintain lumen output by drawing additional current. A second boost converter circuit is associated with a starter circuit arrangement and operates such that starting pulses can be generated and repeated if necessary in a very rapid manner.
    Type: Grant
    Filed: November 24, 1992
    Date of Patent: May 31, 1994
    Assignee: General Electric Company
    Inventors: Joseph M. Allison, Raymond A. Buchina, James D. Mieskowski, Edward J. Thomas, John M. Davenport
  • Patent number: 5309065
    Abstract: A ballast circuit system provides for efficient starting and operation of high voltage discharge lamps using a common 120 volt AC power source. As a result of this improved ballast circuit system, the necessary high voltage is generated from a normal 120 volt AC in such a way that there is low power loss. The system efficiency allows for use of plastic fixtures and small size packaging of the discharge lamp.
    Type: Grant
    Filed: February 26, 1992
    Date of Patent: May 3, 1994
    Assignee: Hubbell Incorporated
    Inventors: Joe A. Nuckolls, Yan Wang
  • Patent number: 5282120
    Abstract: The present invention has an object to develop a converter allowing dielectric strength of a booster transformer to be reduced by half for miniaturization and security thereof. To achieve this object, the booster transformer is provided with first and second secondary coils so that, every time a switching element is turned ON, the first secondary coil generates positive voltage in reference with the negative terminal potential of a DC source while the second secondary coil generates negative voltage also in reference with the negative terminal potential of the DC source and a sum of these positive and negative voltages is output from the converter as a composite voltage.
    Type: Grant
    Filed: March 10, 1992
    Date of Patent: January 25, 1994
    Assignee: Kijima Co., Ltd.
    Inventor: Seiichi Kijima
  • Patent number: 5266869
    Abstract: A discharge lamp lighting apparatus comprises a transformer for stepping up an AC power source voltage from an AC power source to produce a high voltage as an output voltage required for lighting a discharge lamp. Particularly, the lighting apparatus further comprises a diode for rectifying the output voltage of the transformer to be supplied to the discharge lamp. The amount of current supply from the AC power source is determined to obtain an output impedance capable of limiting the current which is to flow through the discharge lamp after the start of discharging to maintain the voltage across the discharge lamp at a level required for continuing the discharge.
    Type: Grant
    Filed: September 24, 1991
    Date of Patent: November 30, 1993
    Assignee: Tokyo Electric Co., Ltd.
    Inventor: Yutaka Usami
  • Patent number: 5258692
    Abstract: An electronic ballast for correcting the power factor within a fluorescent lamp system. Use of an inductor in one of the AC power source leads and selected values of capacitance in a voltage divider and starting circuit combine to provide a power factor greater than 94%.
    Type: Grant
    Filed: June 2, 1992
    Date of Patent: November 2, 1993
    Assignee: Appliance Control Technology, Inc.
    Inventor: William H. Jones
  • Patent number: 5235253
    Abstract: A thin film electroluminescent EL device drive circuit which is capable of applying an AC pulse signal to EL elements contained in the EL device to thereby perform high luminance drive of the EL devices and realize AC pulse drive. With such a drive circuit, it is possible to reduce supply current capacity and power consumption.
    Type: Grant
    Filed: December 14, 1992
    Date of Patent: August 10, 1993
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Yoshihide Sato
  • Patent number: 5229690
    Abstract: An apparatus for operating discharge lamps includes first closed circuit for connecting a discharge lamp through first switching means to a pulsating power source, second closed circuit for connecting the lamp to the power source through a series circuit of second switching means which operates during OFF period of the first switching means and an energy-storing means, and an arrangement for controlling the both switching means. A pulsating source voltage is thereby applied to the discharge lamp. The apparatus is made thus capable at least of minimizing current-limiting impedance and realizing a continuously stabilized discharge of the lamp.
    Type: Grant
    Filed: September 20, 1991
    Date of Patent: July 20, 1993
    Assignee: Matsushita Electric Works, Ltd.
    Inventors: Masahito Ohnishi, Takashi Kanda
  • Patent number: 5196766
    Abstract: A discharge circuit for and method of operating a flashlamp are disclosed in which the flashlamp is reliably operated repetitively while reducing current surges from the electrical power source. A switch means is provided for shunting recharge energy through a non-reactive means around an energy storage means for the flashlamp. The rate of recharging the energy storage means is reduced at the beginning of recharging below the rate which would allow the flashlamp to conduct before intentional triggering of a flash.
    Type: Grant
    Filed: September 4, 1991
    Date of Patent: March 23, 1993
    Inventor: William C. Beggs
  • Patent number: 5191261
    Abstract: A flash lamp power supply system, comprising (a) a simmer power supply circuit, comprising (i) a DC simmer power supply, (ii) means for connecting a flash lamp in series with the DC power supply, and (iii) a capacitor connected in parallel to the power supply and to the flash lamp connecting means, wherein the impedance and capacitance of the simmer power supply are selected so as to provide dV/dT for the simmer power supply circuit equal to or greater than the rate at which the lamp impedance changes during a flash cycle; and (b) a pulse power supply circuit, comprising (i) a DC pulse source voltage supply, (ii) a thyristor, and (iii) means for connecting the lamp in series with the DC pulse source voltage supply and the thyristor, wherein the pulse power supply circuit further comprises a capacitor connected in parallel with the pulse source voltage supply.
    Type: Grant
    Filed: June 11, 1991
    Date of Patent: March 2, 1993
    Assignee: Purus, Inc.
    Inventor: Barton Mass
  • Patent number: 5175474
    Abstract: An apparatus for operating discharge lamp. The apparatus includes a source of electrical power, switching devices for switching the electrical power, a control circuit for controlling the switching devices, a transformer having a primary winding for receiving the electrical power switched by the switching devices and a secondary winding for supplying power to the lighting apparatus, a resonant circuit including an inductor and a capacitor for regulating the frequency of the electrical power and a circuit for powering the control circuit, the powering circuit including a secondary winding on the inductor and an additional winding on the transformer connected in a differential manner.
    Type: Grant
    Filed: September 26, 1991
    Date of Patent: December 29, 1992
    Assignee: Toshiba Lighting & Technology Group
    Inventors: Tsutomu Kakitani, Kenichi Inui
  • Patent number: 5173642
    Abstract: The present invention provides a rare gas discharge fluorescent lamp device which is long in life and high in brightness and efficiency. The lamp device basically comprises a rare gas discharge fluroescent lamp wherein rare gas is enclosed in the inside of a glass bulb which has a fluorescent layer formed on an inner face thereof and has a pair of electrodes at the opposite ends thereof. In one embodiment, it further comprises a dc power source and a resonance circuit for generating pulse-like voltage across the pair of electrodes having the time rate of energization time to a period higher than 5% but lower than 70% and the energization time within a period shorter than 150 .mu.
    Type: Grant
    Filed: June 5, 1991
    Date of Patent: December 22, 1992
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Sadayuki Matsumoto, Takeo Saikatsu, Takehiko Sakurai, Masao Karino, Hiroyoshi Yamazaki
  • Patent number: 5162702
    Abstract: In flashing light warning apparatus of a type having a voltage source (U), a main blocking transformer (HW), a flash tube (R), an ignition device (Z), a first and a third storage condenser (K1, K3), and an electrical switching device (S1), a switching path of the first electrical switching apparatus is arranged parallel to the first storage condenser, the third storage condenser and the ignition device are coupled to an auxiliary blocking transformer (ZW), and the first switching device can be switched by a control device (B). Such a flashing light warning apparatus can be produced in an uncomplicated, cost effective manner, to provide light energy which can be changed during operation to provide a day flash and at least one type of night flash. The night flash is at such a level that its output can be recognized from afar only by night vision apparatus.
    Type: Grant
    Filed: May 8, 1991
    Date of Patent: November 10, 1992
    Assignee: Hella KG Hueck & Company
    Inventors: Siegfried Schmees, Werner Lepper, Wolfgang Grimm, Heiko Janssen
  • Patent number: 5162703
    Abstract: A flashing light warning apparatus, which includes a voltage source (U), a main gate transformer (HW), a flash tube (R), an ignition device (Z), at least one storage condenser (K), and an electrical switching device (S), can be switched to provide light energy for daytime flashes and nighttime flashes in an uncomplicated, cost effective system which produces dependable light flashes. The night flashes have a light energy such that they can be seen from afar only with night vision apparatus. When the switching device turns off voltage production of the main gate transformer or further transmission of voltage from the at least one storage condenser, the ignition device is coupled to an auxiliary gate transformer (ZW) for carrying out light flash production by means of high frequency ignition voltage produced by the ignition device.
    Type: Grant
    Filed: May 8, 1991
    Date of Patent: November 10, 1992
    Assignee: Hella KG Hueck & Company
    Inventors: Siegfried Schmees, Werner Kohl, Wolfgang Grimm, Heiko Janssen
  • Patent number: 5159244
    Abstract: A starter circuit is supplied with 120 volt 60 Hz power, and is coupled to a gas discharge lamp having in an interior thereof a gas and two spaced electrodes. When the starter circuit applies to the electrodes a voltage in excess of a threshold voltage, the lamp transitions from a non-conductive state in which no visible light is emitted to a conductive state in which visible light is emitted. The starter circuit includes several voltage doubler circuits coupled in series with each other between the electrodes of the lamp to form a voltage multiplier circuit. When the lamp is in its non-conductive state, the voltage doubler circuits each output a substantially DC voltage which is twice the maximum potential of the 120 volt input signal so that the voltage multiplier as a whole applies to the electrodes a significant DC voltage in excess of the threshold voltage so that the lamp transitions from its non-conductive state to its conductive state.
    Type: Grant
    Filed: July 17, 1991
    Date of Patent: October 27, 1992
    Inventor: Daniel A. Poulson