Lighting device having LED elements

Abstract

{Technical Problems} To provide a simple style of lighting device using LED {Means for Solving Problems} A lighting device using LED, comprising an LED group 250 configured with series-connected plural number of LED 252 and a driving circuit 550 for feeding the light-emission current to the LED group, wherein the driving circuits 550 has a parallel circuit comprised of a peak current setting capacitor 222 and a resistor 220 connected in parallel thereto, and a full-wave rectification circuit 230 ; wherein the LED group 250 is connected to the output terminal of the full-wave rectification circuit, and the capacitance of the peak current setting capacitor has a value within a region in which the peak value of the pulsating current behaves to increase its value in accordance with the increase of the capacitance of the peak current setting capacitor; wherein an interruption period that is determined in accordance with the number of the series-connections of the LED in the LED group is specified, and the pulsating current, of which peak value is determined in accordance with the capacitance of the peak current setting capacitor, is fed to the LED group.

The invention claimed is: 
     
       1. A lighting device having LED element, comprising
 an LED group having series-connected plural number of LED elements that emit light with feeding a light-emission current and 
 a driving circuit for feeding the light-emission current that flows through the series-connected plural LED elements of the LED group, wherein 
 the driving circuit includes an alternating current power source terminals for receiving supply of alternating current, a peak current control circuit element that controls the peak current of the light-emission current, a full-wave rectification circuit that full-wave rectifies alternating current inputted into an input terminal thereof and outputs pulsating current from an output terminal thereof, wherein 
 the peak current control circuit element and input terminals of the full-wave rectification circuit are provided between the alternating current power source terminals, 
 the LED group is connected between the output terminals of the full-wave rectification circuit, and 
 the peak value of the light-emission current flowing through the LED group is determined in accordance with the peak current control circuit element, wherein 
 the light-emission current fed to the LED group has feeding periods of a low current period that is determined in accordance with the number of the series-connections of LED elements of the LED group and a lighting light-emission period the peak value in which is determined in accordance with the peak current control circuit element, wherein 
 the light-emission current is a pulsating current that flows repeating feeding periods of the low current period and the lighting light-emission period. 
 
     
     
       2. The lighting device having LED element according to  claim 1 , wherein the peak current control circuit element is a peak current control capacitor and the capacitance of a peak current setting capacitor is in a range from 0.5 μF or more to 20 μF or less. 
     
     
       3. The lighting device having LED element according to  claim 2 , wherein the peak current control capacitor has a resistor connected in parallel thereto and the resistance of the resistor is 3 kΩ or larger. 
     
     
       4. The lighting device having LED element according to  claim 1 , wherein the peak current control circuit element is a peak current control resistor and the resistance of the peak current control resistor is in a range from 200 Ω to 700 Ω. 
     
     
       5. The lighting device having LED element according to  claim 1 , further comprising
 a straight tube LED lamp having a resin board therein and 
 a first fixture and a second fixture respectively installed on both ends of the straight tube LED lamp for supporting the lamp, wherein 
 the LED group and the driving circuit are mounted on the resin board, and each of the first and the second fixtures has a lamp mount that secures the end of the straight tube LED lamp, a fixing base for attaching the straight tube LED lamp thereon, and a supporting column that joins the lamp mount integrally to the fixing base. 
 
     
     
       6. The lighting device having LED element according to  claim 1 , further comprising a case that accommodates therein a resin board, wherein the driving circuit is provided on the resin board and the LED elements of the LED group are arranged outer periphery of the driving circuit. 
     
     
       7. The lighting device having LED element according to  claim 1 , wherein the low current period is a current interruption period where the current flowing through the LED group fed from the driving circuit is zero. 
     
     
       8. The lighting device having LED element according to  claim 7 , further comprising a bias current feeding circuit, wherein the bias current feeding circuit feeds at least during the current interruption period. 
     
     
       9. The lighting device having LED elements according to  claim 1 , further comprising a bias current feeding circuit, which provides current to the LED element at least during the low current period. 
     
     
       10. The lighting device having LED elements according to  claim 9 , the bias current feeding circuit having a capacitor between output terminals of the rectification circuit, where the capacitor stores charge and feeds bias current during the low current period. 
     
     
       11. The lighting device having LED elements according to  claim 9 , the bias current feeding circuit having a capacitor, which receives the charging current from the alternating current power source terminals and feeds bias current during the low current period.