Fluorescent LED lighting device and lighting on/off mode switching method therefor
In order to add an emergency light function to a fluorescent LED lighting device, thereby increasing safety during a power outage, this LED lighting device, which can be mounted between a pair of sockets for fluorescent lighting, is equipped with a first power supply circuit, which lights the LED using direct current power obtained by converting/rectifying alternating current power supplied from the sockets, and a second power supply circuit, which lights the LED using an embedded battery. An embedded SW controller detects that a sudden drop in the current value or the voltage value in the lighting device, from a prescribed value Von when the lighting switch is turned on to a value that is essentially zero, occurs within a prescribed time T. When the sudden drop occurs two or more times in the prescribed time (FIG. 5 ), it is determined that a normal operation of turning off the light has been performed, and the light is turned off, and when the sudden drop occurs only once during the prescribed time (FIG. 6 ), it is determined that a power outage has occurred, and the LED is lighted as an emergency light using the second power supply circuit.
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.
2. The fluorescent LED illumination device of claim 1 , wherein said controller discriminates such that the normal light-out operation has been carried out when detecting that sequential OFF→ON→OFF operation of the light switch that was formally ON has been carried out within the predetermined time interval, and thus controls such that the normal lighting mode should be switched to the normal light-out mode.
3. The fluorescent LED illumination device of claim 1 , wherein said controller discriminates such that the normal light-out operation has been carried out when detecting that sequential OFF→ON operation of the light switch that was formerly ON has been carried out within the predetermined time interval, and thus controls such that the normal lighting mode should be switched to the normal light-out mode, said controller constantly monitoring an electricity condition to control such that, as far as that is confirmed, that the LED's are lightened in the normal lighting mode, but once confirming interruption of electricity, said controller controlling such that the normal lighting mode is soon switched to the emergency lighting mode so that the LED's are lightened as an emergency light.
4. A method for switching lighting modes in a fluorescent LED illumination device fittable between a pair of sockets already provided for a fluorescent lamp, including 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, and a second power supply circuit that illuminates the LED's by using an internal buttery, said fluorescent LED illumination device being driven and controlled in either 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 an emergency lamp via said second power supply circuit when an AC power supply is interrupted, said method comprising the steps of detecting a change, within a predetermined time period, of a voltage or current value of electricity flowing into the illumination device, switching the normal lighting mode to the emergency lighting mode, 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, resulting in discrimination that a power failure interrupts the AC power supply, and switching the normal lighting mode to the normal light-out mode, 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, resulting in discrimination that the normal light-out operation has been carried out.