| 摘要 |
<p>PURPOSE:To prevent a smoke-emitting accident when a high-voltage generation part is damaged by a method wherein an electric current route is formed in such a way that a copper-foil pattern used to feed a power supply to a high-voltage generation circuit form a low-voltage power-supply feed part goes around the circumference of the high-voltage generation circuit. CONSTITUTION:A low-voltage power-supply apparatus 1 feeds a power supply to low-voltage power-supply feed parts 4 of a high-voltage power supply apparatus 2. The high-voltage power-supply apparatus 2 is provided with a printed circuit 3 at the inside. The printed circuit 3 is provided with copper-foil patterns 6 to a high-voltage generation circuit 5 from the low-voltage power-supply feed parts 4. The copper-foil patterns 6 are formed on the surface of the printed circuit by etching a copper foil or the like. The copper-foil patterns 6 are formed so as to go around the circumference of the high-voltage generation circuit 5. At the high-voltage generation circuit 5, a voltage is boosted up to a value which is sufficient to ignite a cold-cathode tube 7. When the printed circuit 3 is damaged so as to traverse the high-voltage generation circuit 5 by any cause, the copper-foil patterns 6 are surely cut. At this time, the feed of the power supply to the high-voltage generation circuit 5 is cut, and the operation of the high-voltage generation circuit 5 is stopped. As a result, it is possible to exclude a danger that the printed circuit is carbonized or emits smoke by an arc discharge when a high-voltage part is disconnected.</p> |
