Abstract:
A control unit of a light source device after activation time is configured to turn on switches respectively connected in series with light sources, in prescribed order. The light source device and a lighting device are configured to transmit characteristics of the light sources, based on a voltage change depending on a pattern of on and off of the switches.
Abstract:
A lighting apparatus includes a light source module and a power supply module. The light source module includes an electrical light source and a transmitter circuit configured to transmit a wireless signal containing information about the light source. The power supply module is connected to the light source module and includes a power supply circuit configured to generate electric power for the light source, a receiver circuit configured to receive the wireless signal transmitted from the transmitter circuit, and a control circuit configured to control the power supply circuit in accordance with the wireless signal received through the receiver circuit.
Abstract:
A motor unit for use in an electric bicycle includes a motor, a switching element, a board, and a case. The switching element has the motor driven. The board has a principal surface and a reverse surface. The principal surface includes a mounting surface to mount the switching element thereon. The reverse surface faces opposite from the principal surface. The case houses the board therein. The board further has a through hole provided to penetrate through the board from the mounting surface through the reverse surface and a sheet of metal foil covering an inner peripheral surface of the through hole at least partially. The switching element is thermally connected to the sheet of metal foil. A part, located opposite from the switching element with respect to the board, of the case is thermally connected to the sheet of metal foil.
Abstract:
A lighting device which causes a first light source to emit illumination light and a second light source to emit illumination light having a color temperature higher than a color temperature of the illumination light emitted by the first light source includes: an illuminator which includes a first switching element connected in series to the first light source, and a second switching element connected in series to the second light source; an illumination controller which controls the illuminator to place at least one of the first switching element and the second switching element into an off state; and a constant-current controller which detects a sum of values of currents flowing through the first light source and the second light source, and controls the first switching element and the second switching element based on the sum.
Abstract:
A light-emitting device includes a light emission controller which causes first and second light-emitting element groups to emit light, by supplying undulating voltage to the first and second light-emitting element groups. The light emission controller supplies the undulating voltage to the first light-emitting element group during a first period in which a magnitude of the undulating voltage is greater than a first predetermined value and at most a second predetermined value. The second predetermined value is less than a maximum value of the undulating voltage. The light emission controller supplies the undulating voltage to the first and second light-emitting element groups during a second period in which the magnitude of the undulating voltage is greater than the second predetermined value. The second light-emitting element group surrounds the first light-emitting element group.
Abstract:
A light output control device includes a switching device, multiple signal input ports, a signal selection circuit, and a control circuit. The switching device is to be electrically connected between a direct-current power supply and a light source circuit. The light source circuit includes a semiconductor light emitting element. The multiple signal input ports respectively correspond to multiple kinds of light output control signals. The signal selection circuit selects, when receiving two or more light output control signals indicating different light output levels through the multiple signal input ports, a light output control signal indicating a lowest (or highest) light output level, from the two or more light output control signals. The control circuit performs switching control of the switching device with a duty cycle corresponding to the lowest (or highest) light output level indicated by the light output control signal selected by the signal selecting circuit.
Abstract:
In a lighting device, each of n circuit blocks includes a current controller, a storage element, a charging current controller, a charging rectifier element, and a discharging rectifier element. A first circuit block of the n circuit blocks is configured such that a pulsating voltage generated by rectifying a sine wave AC voltage is applied to the series circuit of the current controller and one light source electrically connected to the first circuit block. An i-th circuit block of the n circuit blocks is electrically connected in parallel to the current controller of an i-1-th circuit block via an i-1-th connection rectifier element.
Abstract:
A lighting device includes a power conversion unit, an impedance adjustment unit, a first control unit, and a second control unit. The power conversion unit is configured to convert input power to direct-current power used for a light source. The impedance adjustment unit is formed of a series circuit of a resistor element and a switch element and is coupled to the light source in parallel, relative to the power conversion unit. The second control unit is configured to cause the power conversion unit to operate, for each burst cycle, for an operation period which is not longer than the burst cycle, and increase and reduce the ratio of the operation period to the burst cycle. The first control unit is configured to make the switch element conductive for a predetermined adjustment period which is not longer than the operation period, during the operation period.
Abstract:
A lighting device includes: a DC power source circuit; an output control circuit including a chopping switch to adjust an output current by chopping of the chopping switch; light source switches respectively connected to the light sources; and a control unit for controlling a time period for which a current flows in the light sources. The control unit controls the output control circuit such that an operation period for which the chopping is conducted and a stop period for which the chopping is stopped are repeated alternately and performs switchover of the light source switches to be sequentially and selectively turned on, and the switchover is conducted during the stop period with a time interval from a beginning of the stop period.