| 摘要 |
<p>PURPOSE: To provide a fly-back transformer having a small-sized low-cost focus pack having a reduced dielectric strength. CONSTITUTION: A fly-back transformer 1 has a primary coil 3 wound with a power coil 24 to produce a d-c voltage covering the voltage adjustable range of a variable resistor 8 and this voltage is applied to the resistor 8 which is housed in a focus pack 11. A medium-voltage coil 27 is wound round the secondary side of a core 2 of the transformer 1 and the low-voltage end of the coil 27 is connected to a slide terminal 18 of the resistor 8. A voltage adjusted by and taken out from the resistor 8 is stepped up by the coil 27 and outputted through a diode 28 as a d-c focus voltage. Since the voltage applied to the resistor 8 is low, the miniaturizing of the focus pack 11 and reduction of the cost can be attained.</p> |
