| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the leakage of noise by making the case body of conductive material, and covering the section excluding a cut or hole section where a high-pressure cord is positioned with a noise shielding member consisting of conductive material. SOLUTION: A discharge lamp lighting circuit 1 accommodates a circuit board mounted with electronic parts within a case 2 made of material having conductivity. A connection cord is led out of the case body 2. A cover 4 is made in plate form which has the same plane form and size as a bottom plate 5 of a box 3. A roughly U-shaped cut is made in the position a little to the front at the right flank of the cover 4. The case body 2 is charged with urethane resin 22 until it reaches the position a little under the top of a peripheral wall 6 of the box 3, covering a starter circuit board 20 and a ballast circuit board 21 from the bottom 5 of the box 3. Hereby, high frequency noise can be prevented from leaking to the outside.</p> |
