| 摘要 |
PURPOSE:To achieve fine input of the electric power by enlarging the delay in the turnoff of No.2 switching element further after the on time of No.1 switching element minimizes, and lessening the high frequency current impressed on a heating coil. CONSTITUTION:Increase/decrease of the input power is made by varying the ratio of turning-on of No.1 and No.2 switching element 2, 3. The delay times of these No.1 and No.2 switching elements 2, 3 are fixed. When the input power is to be further made smaller than 'weak', the delay time td2 of the No.2 switching element 3 is enlarged by a variable delay time generator part 10. Thereby the input power is sunk, and fine input power is accomplished. |
