Panasonic Intellectual Property Management Co., Ltd.

Panasonic Corporation

Matsushita Electric Works, Ltd.

Panasonic Electric Works Co., Ltd.

Akira Nakajo

Hiroshi Kido

Shinji Makimura

Shigeru Ido

Kenichi Fukuda

Masahiro Naruo

Kohji Hiramatsu

Hidenori Kakehashi

Yuji Kumagai

Shohei Yamamoto

Ryusuke Ura

Kazuhiko Harada

Shingo Masumoto

Nadda Chawalarat

Katsuyoshi Goto

The lighting device includes a power conversion circuit and a control circuit. The power conversion circuit includes a high voltage side output terminal and a low voltage side output terminal to be connected to a light source, and a step-down chopper circuit. The control circuit performs a lighting operation of controlling the power conversion circuit to develop a DC output voltage between the high voltage side output terminal and the low voltage side output terminal. The control circuit starts a protective operation of limiting a current to be supplied to the light source when the output voltage is equal to or higher than a threshold value. The threshold value is in a range of 1.2 to 1.3 times a rated voltage of the light source.

Lighting device and illuminating fixture

A lighting device that supplies current to light-emitting units includes: a DC-to-DC converter; a switch unit connected to the light-emitting units; and a control circuit which controls the DC-to-DC converter and the switch unit. The DC-to-DC converter includes: an inductor through which current from the DC-to-DC converter is provided to the light-emitting units; and a first switch element connected in series with the inductor and which switches ON/OFF. The control circuit includes: a zero-crossing detector that detects that current flowing in the inductor is substantially zero due to the first switch element switching OFF, and outputs a zero-current detection signal; and a switch controller that selects one of the light-emitting units and controls the switch unit to cause the current from the DC-to-DC converter to be supplied to the selected light-emitting unit when the first switch element subsequently switches ON, each time the switch controller receives the zero-current detection signal.

Lighting device and luminaire

Provided is a lighting device including two switching elements, a control circuit, a resonance circuit, a rectification circuit, and a feedback circuit. The control circuit controls two switching elements such that the two switching elements operate separately from each other. The control circuit changes the switching frequencies of the two switching elements from high frequencies to low frequencies, relative to one another, when the operation (switching operation) of the switching elements is started. The control circuit controls the feedback circuit such that the difference output from an error amplifier approaches zero within a period of time from a point of time at which the switching operation is stopped to a point of time at which the switching operation is next started.

Lighting device and lighting fixture using same

A lighting device includes: a DC/DC converter including two switching elements connected in series and a resonant circuit connected to a connection point between the two switching elements; and a control unit configured to control driving of the two switching elements. The control unit is configured to: perform intermittent driving in which a switching period and a non-switching period are alternately repeated, the switching period being a period in which the control unit switches ON and OFF the two switching elements respectively and inversely; and the non-switching period being a period in which the control unit stops switching ON and OFF the two switching elements; and provide, in an initial part of the switching period, a frequency gradual decrease period in which a driving frequency for driving the two switching elements is gradually decreased.

The light emitting element lighting device in accordance with the present invention, includes: a light emitting unit including a light emitting element; and a power supply circuit configured to supply a supply voltage to the light emitting unit. The power supply circuit is configured to increase the supply voltage from a first voltage lower than a lighting start voltage of the light emitting element to a second voltage higher than the lighting start voltage to light up the light emitting unit. The power supply circuit is configured to, in a process of increasing the supply voltage from the first voltage to the second voltage, decrease a rate of increase in the supply voltage as the supply voltage gets closer to the second voltage.

Light emitting element lighting device and lighting fixture using same

A light emitting element lighting device includes: a rectifying unit which rectifies an AC voltage; a smoothing unit which smoothes a ripple voltage from the rectifying unit; a power supply unit having a switching element; and a control unit which controls on/off of the switching element. Further, the smoothing unit servers as a partial smoothing circuit for partially smoothing a low voltage period of the ripple voltage outputted from the rectifying unit. The power supply unit supplies a lighting power to a light source unit including one or more light emitting elements. The control unit controls a switching frequency of the switching element to decrease as the output voltage of the smoothing unit decreases.

Lighting device and illumination apparatus using same

A wireless power supply system for lighting includes: a power transmission unit including a power transmission coil; and a power reception unit including a power reception coil. The power transmission coil generates an AC magnetic field in response to a supplied AC power. The power reception coil receives an electric power from the power transmission unit through an electromagnetic induction due to the AC magnetic field generated by the power transmission coil. The power reception unit further includes a power circuit and a receive-side control section. The power circuit receives an output power from the power reception coil and to perform Buck-Boost operation so as to output a predetermined electric power to a lighting load. The receive-side control section controls the Buck-Boost operation of the power circuit. The power circuit is configured to be capable of boosting and stepping-down of the output power from said power reception coil.

Wireless power supply system for lighting and lighting apparatus

An object of the present invention is to provide an organic EL element lighting device whereby surge current can be reduced at start-up while controlling start-up variation, along with a lighting fixture using the same. Provided are a current supply part for supplying lighting current to a light source formed of one or more organic EL elements and connected between output terminals of the current supply part, a current detection part for detecting the lighting current, a target setting part for setting a target value of the lighting current, and a control part for performing feedback control of the lighting current by controlling the current supply part so that the detected value of the current detection part matches the target value of the lighting current. The target setting part has a sweep period during which the target value is gradually increased at start-up of the light source.

Organic EL element lighting device and lighting fixture using the same

A lighting apparatus includes a lighting circuit unit, a timer unit, a life judgment unit, a timing adjustment unit, and an indication unit. The lighting circuit unit is configured to activate a light source. The timer unit is configured to measure accumulated operation time of the lighting circuit unit. The life judgment unit is configured to store a first judgment time and a second judgment time longer than the first judgment time. The life judgment unit is configured to compare the accumulated operation time with the first judgment time and output a first judgment signal when the accumulated operation time becomes equal to the first judgment time. The life judgment unit is configured to compare the accumulated operation time with the second judgment time and output a second judgment signal when the accumulated operation time becomes equal to the second judgment time. The timing adjustment unit is configured to vary timing at which the life judgment unit outputs the first judgment signal. The timing adjustment unit is configured to vary timing at which the life judgment unit outputs the second judgment signal. The indication unit is configured to indicate, upon receiving the first judgment signal from the life judgment unit, a first level of the end of life with the light source kept turned on. The indication unit is configured to indicate, upon receiving the second judgment signal from the life judgment unit, a second level of the end of life. The second level of the end of life is later than the first level of the end of life.

Lighting apparatus and lighting fixture

An induction lamp lighting device includes an induction coil arranged adjacent to an induction lamp; a direct current power supply circuit for outputting a direct current voltage; a high-frequency power supply circuit for converting the direct current voltage to an alternating current voltage and supplying the alternating current voltage to the induction coil; and a control circuit for controlling the direct current power supply circuit and the high-frequency power supply circuit. The control circuit performs a startup preparation operation by which to control the high-frequency power supply circuit so that, immediately after the alternating current voltage begins to be outputted from the high-frequency power supply circuit to the induction coil, the alternating current voltage is gradually increased to such a voltage value as not to generate arc discharge in the induction lamp and then kept at the voltage value for a specified time.

Induction lamp lighting device and illumination apparatus

There is provided an electrodeless discharge lamp lighting device with small size and low cost by simplifying a noise suppression part and a lighting apparatus having the electrodeless discharge lamp lighting device. A counter circuit of a frequency signal generating circuit repeatedly generates a frequency signal of which the amplitude is varied in a multi-step shape on the basis of an oscillation period of an oscillation circuit. An oscillation circuit outputs an oscillation signal of a frequency corresponding to the amplitude of the frequency signal. A drive circuit drives a switching element of an inverter circuit at the frequency of the oscillation signal and the inverter circuit applies a high-frequency voltage generated by the switching operation of the switching element to an induction coil to start up and light the electrodeless discharge lamp. That is, a high-frequency voltage which is varied at three discrete frequencies f, f, and fis repeatedly and periodically applied to the induction coil and thus a magnetic-component noise generated from a discharge lamp lighting device is distributed into three frequency components.

Electrodeless discharge lamp lighting device and lighting apparatus

A ballast for an electrodeless discharge lamp includes a high frequency power supply that supplies a high frequency electric power to an induction coil for operating the lamp. A dimmer controller generates a control signal in response to a dimmer command designating a varying dimming ratio. The control signal defines a first period Ton in which the power supply is controlled to apply a coil voltage of a first level Vto the induction coil for operating the lamp. The first period is followed by a second period Toff in which the power supply is controlled to apply the coil voltage of a second level Vthat is lower than the first level and fails to sustain the lamp. The control signal defines, between the second period and the first period, a starting period Tst in which the coil voltage increases continuously for smooth transition from an off-condition to an on-condition of the lamp.

Growing community of inventors

Kyoto, Japan

Akira Nakajo