Panasonic Intellectual Property Management Co., Ltd.

Tomohiro Miyake

Kiyosi Gotou

Kengo Miyamoto

Eiichirou Niikura

Takeo Suzuki

Kiyoshi Goto

Masayuki Nakamura

A bidirectional switch switched to conduct and interrupt a bidirectional current between a pair of input terminals. An input device receives a dimming level representing a value of light output of the load. A controller controls the bidirectional switch according to the dimming level. The controller controls the bidirectional switch to keep the bidirectional switch in an off-state from a start point of a half cycle of the AC voltage of the AC power supply to a first time point when a first time period therefrom elapses, and to turn the bidirectional switch to an on-state at the first time point. The controller turns the bidirectional switch to the off-state at a second time point when a second time period elapses from the first time point. The controller keeps the bidirectional switch in the off-state from the second time point to an end point of the half cycle.

Dimmer

A power supply is electrically connected between a pair of input terminals and is configured to be supplied with electric power from an AC power supply to generate control electric power. A voltage detector is configured to detect a voltage of the control electric power. A controller is configured to be supplied with the control electric power from the power supply to operate. The controller is configured to control a bidirectional switch based on a detection signal from a phase detector so as to switch the bidirectional switch from an ON state to an OFF state at a switching time point when a variable time corresponding to a dimming level elapses from a starting point of a half period of an AC voltage. A stopper is configured to halt generation of the control electric power by the power supply when the voltage detected by the voltage detector is higher than or equal to a prescribed threshold during an OFF time period from the switching time point to an end time point of the half period.

Lighting control device

A control unit controls a bidirectional switch so as to turn the switch from ON to OFF when an amount of time, varying according to a lighting level, passes since a starting point of a half cycle of an AC voltage. When a voltage between both terminals of a capacitive element, connected to a control terminal of the bidirectional switch, becomes equal to or greater than a threshold voltage, the bidirectional switch turns from OFF to ON A first charging/discharging regulator circuit and a second charging/discharging regulator circuit each make a rate of fall of the voltage between both of the terminals of the capacitive element when the bidirectional switch turns from ON to OFF lower than a rate of rise of the voltage between both of the terminals of the capacitive element when the bidirectional switch turns from OFF to ON.

Protection circuit for dimmer, and dimmer

A bidirectional switch is switched so as to conduct and interrupt a bidirectional current between a pair of input terminals. A power supply is electrically connected between the pair of input terminals and produces control power by electric power from an AC power supply. A controller receives the control power from the power supply to be activated. The controller causes the bidirectional switch to be in an off-state from a start point of a half cycle of AC voltage to a first time point when a first time period elapses. The controller causes the bidirectional switch to be in an on-state from the first time point to a second time point when a second time period according to the dimming level elapses. The controller causes the bidirectional switch to be in an off-state from the second time point to an end point of the half cycle.

A lighting control device includes a bidirectional switch, an inputter, a controller, and a corrector. The bidirectional switch is configured to switch between conduction and non-conduction of a bidirectional current between a pair of input terminals. The inputter is configured to receive a dimming level specifying the magnitude of a light output of a load. The controller is configured to control the bidirectional switch so as to retain the bidirectional switch in an ON state for an on time having a length determined in accordance with the dimming level within a prescribed range in each of half periods of an AC voltage of an AC power supply. The corrector is configured to (i) determine whether or not a target waveform has an anomaly with reference to a prescribed determination condition, and (ii) correct the prescribed range so as to narrow the prescribed range when the target waveform has the anomaly; wherein the target waveform is a waveform of at least one of a voltage and a current input to the pair of input terminals.

Lighting control device having a corrector integrally with a controller thereof for correcting a dimming prescribed range stored therein

In a light-dimming device according to an example of the present invention, a controller is configured to be supplied with control electric power from an electricity accumulator to operate and to retain a bidirectional switch in an on state for an on time having a length according to a dimming level in every half period of an AC voltage of an AC power supply in a lighting mode. A charger including a first charger and a second charger causes a current to flow from a pair of input terminals and to the electricity accumulator. An impedance of the second charger which is a charger in a case of causing a current to flow to the electricity accumulator in the lighting mode is lower than an impedance of the first charger which is a charger in a case of causing a current to flow to the electricity accumulator in a non-lighting mode.

Light-dimming device

A bidirectional switch is switched so as to conduct and interrupt a bidirectional current between a pair of input terminals. A power supply is electrically connected between the pair of input terminals and produces control power by electric power from an AC power supply. A controller receives the control power from the power supply to be activated. The controller causes the bidirectional switch to be in an off-state from a start point of a half cycle of AC voltage to a first time point when first time elapses. The controller causes the bidirectional switch to be in an on-state from the first time point to a second time point when second time according to the dimming level elapses. The controller causes the bidirectional switch to be in an off-state from the second time point to an end point of the half cycle.

A signal source generates a drive signal according to a dimming level. A discharge part includes a series circuit having a Zener diode and a rectifier element connected in series. The series circuit enables passage of a reverse current of the Zener diode. In the discharge part, the series circuit is electrically connected between a control terminal and the signal source to enable the reverse current of the Zener diode to flow from the control terminal to the signal source.

Dimming device

The dimming device includes a pair of input terminals, a bidirectional switch, an inputter, a power supply, a controller, and a current limiter. The power supply is electrically connected between the pair of input terminals and is supplied with electric power from an AC power supply to generate control electric power. The controller is supplied with the control electric power from the power supply to operate. The controller is configured to control the bidirectional switch in accordance with a dimming level. The current limiter stops generation of the control electric power by the power supply when a current larger than or equal to a specified value flows from the AC power supply through the power supply.

Growing community of inventors

Mie, Japan

Tomohiro Miyake