LAMP-LIGHTING EQUIPMENT FOR LIGHTING EQUIPMENT AND LIGHTING EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To make a dimmer of a lighting equipment of an inverter system possible, without preparing a special oscillation circuit. SOLUTION: The lamp-lighting equipment is equipped with an active converter 4 which generates a direct-current voltage from commercial alternate voltage, and the inverter 5 which supplies high frequency current to a discharge tube 1 by switching the generated direct-current voltage through a resonance circuit where resonance frequency becomes settled according the equivalent impedance of the discharge tube 1 including a capacitor CR connected in parallel with the discharge tube. The active converter 4 has a triac 7 which adjusts the value of the direct-current voltage, and switching elements Q1 and Q2 of the inverter 5 are controlled by a phase of resonance current flowing in the resonance circuit, and oscillate by self-excitation.