| 摘要 |
PURPOSE:To compact the titled device in size and weight and to reduce power consumption by connecting a primary winding of a heater transformer to supply a large current with low voltage in parallel with the primary winding of a power source insulation transformer and selecting a large winding ratio of the heater transformer. CONSTITUTION:A primary exciting radio wave for heater transformer 27 is a smooth sine wave whose current is of a small value. In the transformer 27, a ferrite core made of materials U-14 and FE-2 is used, and its winding is made of a bundle of thirty-eight thin core wires of a diameter of 0.1mm, and the secondary winding NH2 and NH2 are made by three turns of said wires. The number of turns of primary winding NH1 is two hundred and fifty. Accordingly, the winding ratio of the transformer 27 is improved remarkably from 2.33 to 83.3. Therefore, the primary exciting current of th4e transformer 27 decreases in proportion to the winding ratio. As a result, the AC-DC conversion efficiency improves up to approximately 87% and the power consumption decreases by about 3.4W. |
