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| 20100084988 | DISCHARGE LAMP LIGHTING DEVICE, LIGHTING FIXTURE, AND LIGHTING SYSTEM - A discharge lamp lighting device includes: a direct current power supply circuit that outputs direct current power; an inverter circuit that converts the direct current power, which is outputted by the direct current power supply circuit, into alternating current power, and supplies the alternating current power to a discharge lamp; a control circuit that controls a frequency of an output of the inverter circuit (operation frequency); and a starting detection circuit that detects beginning (starting) of a discharge in the discharge lamp. The control circuit operates in a starting improvement mode, in which the operation frequency is lowered than an operation frequency in a lighting mode, during a predetermined time from when the starting of the discharge lamp is detected by the starting detection circuit | 04-08-2010 |
| 20100109543 | HIGH-PRESSURE DISCHARGE LAMP BALLAST WITH MULTI-MODE LAMP STARTING CIRCUIT - An electronic ballast is provided for powering a high-pressure discharge lamp. A power supply circuit receives an AC input and provides a DC output in response to the AC input. An inverter circuit having a plurality of switching elements converts the DC output into an AC signal for the lamp. An LC resonant circuit is coupled between the inverter circuit and the lamp. A control circuit controls the switching operation of the switching elements, with the switching control associated with various operating modes. In an electrical breakdown mode the switching elements are controlled at a first switching frequency effective to provide a first resonant voltage and produce electrical breakdown of the lamp from an unlit state. In a high frequency preheat mode the switching elements after startup of the lamp are controlled at a second switching frequency lower than the first switching frequency to provide a current for preheating lamp electrodes. In a rectangular wave lighting mode the switching elements after preheating of the lamp electrodes is controlled to supply a rectangular wave AC signal to the lamp and maintain steady state lighting. | 05-06-2010 |
| 20100109546 | ELECTRONIC BALLAST WITH LAMP FLICKER SUPPRESSION DURING START-TO-STEADY STATE TRANSITION - An electronic ballast is provided for powering a discharge lamp and suppressing lamp flicker during startup transition. A power converter receives DC input power and converts it into an AC power output. A resonant circuit is coupled with the lamp and also between output terminals of the power converter. A controller controls the power converter with respect to particular modes of operation. The controller in a starting operation sets the output frequency of the power converter to a predetermined start frequency upon lamp startup to make the lamp begin discharging. The controller shifts from the starting operation to steady-state operation by setting the output frequency of the power converter at a predetermined steady-state frequency lower than the start frequency. The predetermined start frequency is set to a frequency identical or close to 1/(an odd whole number) of the resonant frequency of the resonant circuit with the lamp unlit, and also to a frequency identical or close to the resonant frequency of the resonant circuit with the discharge lamp lit. The start frequency is sufficient to make the discharge lamp start discharging, and to raise a temperature of each electrode of the discharge lamp after lamp startup and by an end of the starting operation. | 05-06-2010 |
| 20100237794 | DISCHARGE LAMP BALLAST WITH FEEDBACK CURRENT CONTROL DURING AN ELECTRODE HEATING OPERATION - A discharge lamp ballast is provided with a feedback control operation to provide optimal lamp current flow during an electrode heating operation. A startup circuit coupled together with a discharge lamp between output terminals of a DC-AC power converter having a plurality of switches. The startup circuit generates a high voltage to ignite the lamp. A lamp current sensor detects an amplitude of an output current to the lamp. A control circuit controls the switches in accordance with each of a plurality of control operations including a startup operation to ignite the lamp using the high voltage generated by the startup circuit, an electrode heating operation wherein an operating frequency of the switches is controlled to set the amplitude of the detected output current to a predetermined target current amplitude, and a normal operation wherein the operating frequency is reduced to maintain stable lighting of the lamp. | 09-23-2010 |
| 20110074307 | ELECTRONIC BALLAST AND METHOD FOR PROVIDING A DC VOLTAGE COMPONENT DURING LAMP STARTUP - A discharge lamp ballast and method of operation are provided for generating a DC component in an output voltage during a lamp starting operation having a predetermined duration. The ballast includes an inverter having four switches arranged in a full-bridge configuration, a resonant circuit having a resonant frequency, and a control circuit. The method includes a step of sweeping an inverter operating frequency within a predetermined frequency range including the resonant frequency, wherein a high voltage is generated for igniting the lamp. The method further includes periodically and alternately repeating a first state of turning on a first set of diagonally positioned switching elements and turning off a second set of diagonally positioned switching elements, and a second state of turning on only one of the second set of switching elements and turning off the remaining three switching elements, respectively. | 03-31-2011 |
| 20110149543 | PRINTED WIRING BOARD CONNECTION STRUCTURE - A printed wiring board connection assembly includes a first printed wiring board and a plurality of connecting pieces having a first connecting pattern made of an electrically conductive material formed on first and second opposing surfaces. A second printed wiring board has a plurality of connecting holes shaped to receive respective connecting pieces and having second connecting patterns arranged to correspond with the first connecting patterns of the respective connecting pieces. Each of the connecting pieces has one or more through-holes extending between the opposing surfaces of the respective connecting pieces and positioned such that upon receiving of the connecting pieces by the respective connecting holes a portion of at least one through-hole is exposed proximate the first surface of the second printed wiring board and a portion of at least one through-hole is exposed proximate the second surface of the second printed wiring board. | 06-23-2011 |
| Patent application number | Description | Published |
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| 20100327775 | HIGH PRESSURE DISCHARGE LAMP LIGHTING DEVICE AND LIGHTING FIXTURE USING THE SAME - A high pressure discharge lamp lighting device comprising an inverter, an igniter, a controller, a pulse voltage detection circuit, and the starting pulse voltage regulation circuit. The inverter applies a lighting voltage to a high pressure discharge lamp. The controller applies the starting pulse voltage generated by the igniter to the high pressure discharge lamp. The pulse voltage detection circuit is configured to detect a voltage indicative of the starting pulse voltage to output a detection signal. The starting pulse voltage regulation circuit is configured to regulate the starting pulse voltage to a desired value of the starting pulse voltage on the basis of the detection signal. The pulse voltage detection circuit is configured to detect either one of the voltage developed in the specified circuit component of the igniter and the starting pulse voltage as the voltage indicative of the voltage indicative of the starting pulse voltage. | 12-30-2010 |
| 20100327776 | HIGH PRESSURE DISCHARGE LAMP LIGHTING DEVICE AND LIGHTING FIXTURE USING THE SAME - A high pressure discharge lamp lighting device in this invention comprises a converter, an inverter, an igniter, a controller, and a pulse voltage detection circuit. The converter outputs the direct current voltage. The inverter converts the direct current voltage into the lighting voltage which is alternating current voltage, and applies the lighting voltage to the high pressure discharge lamp through an output terminal. The igniter is configured to output the pulse voltage superimposed on the lighting voltage, whereby the starting voltage is applied to the high pressure discharge lamp. The controller is configured to control the igniter to allow the igniter to superimpose the pulse voltage on the lighting voltage. The pulse voltage detection circuit detects the starting voltage to output the detection signal. The starting voltage regulation circuit regulates the starting voltage to the desired voltage value of the voltage on the basis of the detection signal. | 12-30-2010 |
| 20110068714 | HIGH PRESSURE DISCHARGE LAMP LIGHTING DEVICE AND ILLUMINATION INSTRUMENT - In an event of switching a DC output voltage of a boost chopper circuit from a first DC output voltage to a second DC output voltage, a boost chopper control circuit operates a boost chopper circuit intermittently. Therefore, a stop period of the boost chopper circuit is shortened as compared with a case where the boost chopper control circuit does not operate the boost chopper circuit intermittently. As a result, it becomes possible to supply a control power also when the DC output voltage of the boost chopper circuit is switched at a starting time of a high pressure discharge lamp while avoiding size and cost increases of a power supply circuit that supplies the control power. | 03-24-2011 |
| 20110074311 | HIGH-VOLTAGE DISCHARGE LAMP LIGHTING DEVICE AND LIGHTING FIXTURE - A device includes a direct current power circuit configured to convert an alternating current voltage from an alternating current power source into a direct current voltage, an output unit configured to convert a direct current from the direct current power circuit into a square wave alternating current whose polarity is inverted at a prescribed frequency and to supply the square wave alternating current to a high-pressure discharge lamp, a controller, and an anomaly detector configured to detect an instantaneous voltage drop of the alternating current power source. When the anomaly detector detects the instantaneous voltage drop, the controller switches from a normal lighting mode of controlling the output unit to supply the high-pressure discharge lamp with a square wave alternating current to a lighting maintained mode of controlling the output unit to supply the high-pressure discharge lamp with a square wave alternating current having a lower frequency than the square wave alternating current in the normal lighting mode. In this way, it is possible to maintain lighting of the high-pressure discharge lamp even upon occurrence of an instantaneous power failure, an instantaneous voltage drop, and the like. | 03-31-2011 |
