| 摘要 |
PURPOSE: To control substantially proportional power for a probe by automatically tuning the mechanical resonance frequency of the probe, and extracting a reactive component of load impedance to be automatically tuned. CONSTITUTION: A microprocessor 808 controls all functions executed by this system. A probe 24 is a metallic rod having a projecting nose piece and a conical mechanical amplifier section, and is buried in a metallic part. A pair of piezo crystal elements 28 and 30 are provided, and these excite the metal of the probe 24, so that when the crystals are vibrated in response to an electric driving signal on lines 836 and 838, they are vibrated at the mechanical resonance frequency. This is performed by a voltage control oscillator 56. An output signal of the voltage control oscillator on a line 72 is applied to an input end of a linear driving amplifier 74. Thus, a signal on the bus 72 is amplified and applied to the primary winding of a voltage setup transformer. |
