A high-frequency heating method for a progressive die using a high-frequency heating apparatus for the progressive die, the high-frequency heating apparatus comprising:
- an open-top shield housing (200) made of a ferrite material which shields electromagnetic waves;
- a plurality of main high-frequency oscillation members (300) radially arranged around a center of the shield housing (200);
- main extension/reduction transfer members (400) configured to transfer the main high-frequency oscillation members (300) in directions in which an arrangement radius is selectively extended and reduced;
- and
- a high-frequency oscillation controller (500) configured to activate the main high-frequency oscillation members (300) by applying high-frequency signals to the main high-frequency oscillation members (300), thereby causing the main high-frequency oscillation members (300) to generate high-frequency waves;
- wherein each of the main high-frequency oscillation members (300) comprises:
- a main oscillator housing (310) configured to have a high-frequency wave emission hole (311) in a top thereof;
- a main high-frequency oscillator (320) configured to generate high-frequency waves via the high-frequency wave emission hole (311) in a state of being installed inside the main oscillator housing (310);
- and a main high-frequency wave disperser (330) coupled to the top of the main oscillator housing (310), and configured to have a high-frequency wave dispersion hole (331) adapted to disperse the high-frequency waves, emitted via the high-frequency wave emission hole (311), to an outside;
- and
- wherein the main extension/reduction transfer members (400) comprise respective main solenoid plungers (410) configured to selectively move the main oscillator housings (310), containing the respective main high-frequency oscillators (320), forward and backward in a direction of a center of the shield housing (200) in a state of being radially installed along an outer circumferential surface of the shield housing (200);
- the method comprising:
- when an object (1) to be heated reaches a predetermined location, detecting a heating target point (1a) of the object (1) to be heated by means of a location detection sensor (600) while a main solenoid plunger is selectively moving forward and backward;
- when the heating target point (1a) is detected, arranging the specific main high-frequency oscillation member at a location, at which the main high-frequency oscillation member can heat the heating target point (1a) of the object (1) to be heated, by stopping the main solenoid plunger at a detection point;
- arranging all main high-frequency oscillation members (300), connected to remaining main solenoid plungers, at locations, at which the main high-frequency oscillation members (300) can heat the heating target point (1a) of the object (1) to be heated, by operating the remaining main solenoid plungers to the location, at which the main solenoid plunger has been stopped, by means of a control unit (700);
- detecting a thickness of the object (1) to be heated, and setting high-frequency oscillation time in the main high-frequency oscillators (320) in proportion to the thickness;
- and
- heating the heating target point (1a) of the object (1) to be heated by generating high-frequency waves by means of the main high-frequency oscillators (320) in accordance with the set time.