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Akira Yufuku

Akira Yufuku, Himeji-Shi JP

Patent application numberDescriptionPublished
20100117547LAMP BALLAST AND AN ILLUMINATION APPARATUS - A lamp ballast capable of lighting a discharge lamp and an incandescent lamp each at an optimum condition. The lamp ballast has a DC-DC converter, an inverter that converts an output of DC-DC converter into an AC power for applying the same to a lamp load, a starting circuit generating a high voltage pulse from the AC power to provide the same to the lamp load, and a controller that controls the DC-DC converter and the inverter to provide a variable DC voltage and the AC power of variable frequency. The controller has a starting mode of operating the inverter at a starting frequency to generate the high voltage, and a lighting mode of operating the inverter at a lighting frequency lower than the starting frequency. The controller has a detection mode of causing the DC-DC converter to output a detection voltage of a predetermined level prior to the starting mode, a discharge lamp lighting program of operating, after the detection mode, the inverter in the starting mode and subsequently in the lighting mode, and an incandescent lamp lighting program of operating, after the detection mode, the inverter in the lighting mode without through the starting mode. When the detection voltage exceeds a predetermined threshold, the controller selects the discharge lamp lighting program, and otherwise selects the incandescent lamp lighting program. When the incandescent lamp is connected, the ballast turns on the incandescent lamp without applying a high voltage pulse so as to avoid lowering of the lamp life.05-13-2010
20100327775HIGH 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
20100327776HIGH 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

Akira Yufuku, Himeji JP

Patent application numberDescriptionPublished
20100013398High Voltage Discharge Lamp Lighting Device - A high-voltage discharge lamp lighting device provides a starting pulse voltage sufficient to turn on a high-voltage discharge lamp having terminal wire connections of variable length. A power conversion circuit is coupled to a commercial AC power source input and rectifies the AC input into a predetermined DC voltage output. A charging capacitor is coupled to the power conversion circuit. A full bridge circuit is coupled to the power conversion circuit and the charging capacitor and provides a rectangular wave AC output signal to a transformer primary winding circuit of at least a capacitor, a single switching element and a primary winding of a transformer. A low pulse voltage is induced in the primary winding and a transformer secondary winding is connected on one end to the high-voltage discharge lamp, wherein the low pulse voltage is stepped up to a high pulse voltage and applied to the high-voltage discharge lamp. A reference voltage is generated in a reference transformer winding representative of the high pulse voltage. A starting pulse equivalent value detection circuit is connected to the reference winding and detects a value associated with the reference voltage. A control circuit receives said value from said detection circuit, and variably controls at least one of a frequency of the single switching element or an ON impedance of the single switching element in association with said value, wherein said frequency or ON impedance is further associated with a starting pulse voltage sufficient to start the high-voltage discharge lamp.01-21-2010
20100109572HIGH-PRESSURE DISCHARGE LAMP BALLAST WITH RAPID LAMP RESTART CIRCUIT - An electronic ballast is provided for quickly restarting a high-pressure discharge lamp after shutdown. The ballast includes a power supply circuit for supplying power to the lamp from a commercial power source, a start voltage generation circuit for supplying a starting high voltage to the lamp and a control circuit for controlling the power supply circuit and the start voltage generation circuit. A lighting transition module detects a startup or shutdown of the lamp. A lighting time count module measures a lighting time of the lamp when startup is detected. A comparison module compares the lighting time and a first reference time when shutdown is detected. A delay time setting module sets a predetermined delay time of the start voltage generation circuit based on the comparison result. Operation of the ballast is halted from a startup trigger until lapse of the delay time, and then the high starting voltage is supplied to the lamp.05-06-2010
20100156312ELECTRONIC BALLAST FOR RESTARTING HIGH-PRESSURE DISCHARGE LAMPS IN VARIOUS STATES OF OPERATION - A high-pressure discharge lamp ballast is provided for igniting and re-igniting a high-pressure discharge lamp in various states of operation. A power supply circuit is coupled to a power source and supplies AC power to the lamp. An ignition voltage generating circuit supplies a high-voltage ignition pulse for igniting the lamp. A pulse control circuit alternatively controls the ignition voltage generating circuit in a first control mode to provide the high-voltage ignition pulses for a first time period and in a second control mode to delay the high-voltage ignition pulses for a second time period. An abnormality detection circuit detects an abnormal lighting state of the lamp wherein a measured condition of the lamp corresponds to a predetermined condition. The pulse control circuit increases a ratio of the second time period relative to the first time period upon detection of an abnormal lighting state of the lamp by the abnormality detection circuit.06-24-2010
20100195297ELECTRONIC BALLAST WITH GROUNDING SPACER AND INSULATING FILLER - An electronic ballast provides a ballast housing including a circuit board electrically and mechanically connected to the ballast housing by an electrically conductive spacer. The circuit board includes a ground electrode surrounding a clearance hole through which an electrically conductive fastener is inserted into a fastener hole located in the spacer. An insulating filler is disposed in the ballast housing between the housing interior surface and the circuit board. A lighting fixture including an electronic ballast is also provided.08-05-2010

Akira Yufuku, Hirakata JP

Patent application numberDescriptionPublished
20090146579DISCHARGE-LAMP LIGHTING DEVICE AND LUMINAIRE - There is provided a discharge-lamp lighting device that, upon start-up of a high-intensity discharge lamp, alternately outputs a period A during which a starting circuit applies a high voltage to the high-intensity discharge lamp by resonance operation when a DC/AC inverter outputs a high-frequency voltage, and a period B during which the DC/AC inverter applies a low-frequency-square-wave voltage or a DC voltage to the high-intensity discharge lamp via the starting circuit. The period A for applying the high voltage by the resonance operation is set to about a time enough for a high-intensity discharge lamp in an initial aging stage to cause a dielectric breakdown, and a period C for alternately outputting the high-voltage generating period A and the period B for outputting the low-frequency-square-wave voltage or the DC voltage is set to about a time enough for a high-intensity discharge lamp in a life's last stage to cause a dielectric breakdown.06-11-2009
20090236999DISCHARGE LAMP LIGHTING DEVICE AND LIGHT FIXTURE - In a discharge lamp lighting device that, at a time of starting a discharge lamp La, alternately repeats periods HF09-24-2009