LEAKAGE ALARM DEVICE OF EARTH LEAKAGE BREAKER

摘要

PROBLEM TO BE SOLVED: To provide stable alarm signals and to simplify installation and constitution by detecting using a light projecting element and a light interrupting element that a leakage indicating button is projecting, and transmitting a leakage signal from a photoelectric switch. ;SOLUTION: A light projecting element 10 and a light interrupting element 11 have their respective optical axes made to pass through the center of a leakage indicating button 2, and light-transmitting holes 13 are bored in two parts of a light-blocking wall 7a along the optical axes. Round holes are bored in a printed substrate and in the upper wall of a case 6 in such a way as to face the button 2, and a lid plate 14 is mounted in the round hole in the case 6. The button 2 is always held in a predetermined position, and the light from the light projection ion element 10 is received by the light interrupting element 11 through the light transmitting walls 13, with not leakage signal produced. During leakage breaking, the button 2 is projecting, and the light from the light projector 10 is blocked and does not impinge on the light interrupting element 11, so a leakage signal is transmitted from an output wire. Since the inside of a housing is matte black and the periphery of the button 2 is covered with the light-blocking wall 7a, the light does not go around them as the result of irregular reflections.;COPYRIGHT: (C)1997,JPO