Patent ID: 9729005
Date: 2017-08-08
CPC Classifications: H02J,H05B,Y02B

Claim:
1. A fluorescent LED illumination device fittable between a pair of sockets already provided for a fluorescent lamp, comprising a first power supply circuit that illuminates LED's by using a DC power obtained by converting and rectifying an AC power supplied from the sockets, a second power supply circuit that illuminates the LED's by using an internal buttery, and a controller that discriminates one of a normal lighting mode wherein the LED's are lightened via said first power supply circuit or said second power supply circuit when a light switch is ON, a normal light-out mode wherein the LED's are not lightened when said light switch is OFF and an emergency lighting mode wherein the LED's are lightened as emergent lights via said second power supply circuit when an AC power supply is not alive, said controller further operating, in response to a result of said discrimination, to select an applicable one among said normal lighting mode, said normal light-out mode and said emergency lighting mode, said contoller detecting a change, within a predetermined time interval, of a voltage or current value of electricity flowing into the illumination device to discriminate such that, when detecting that, within the predetermined time interval, said value is lowered only one time from a predetermined value of electricity that will normally flow when the light switch is ON to substantially zero, which remains standstill, a power failure interrupts the AC power supply, to control such that the normal lighting mode should be switched to the emergency lighting mode, whereas, when detecting that, within the predetermined time interval, there occurs a change of the current or voltage value including a decrease from the predetermined value of electricity that will normally flow when the light switch is ON to substantially zero, followed by an increase to said predetermined value, the normal light-out operation has been carried out to control such that the normal lighting mode should be switched to the normal light-out mode.