BUILDING OF A ROTARY HEAD FOR ULTRASONICALLY AIDED ELECTRICAL DISCHARGE MACHINING
The paper deals with a rotary head for ultrasonically aided electrical discharge machining (EDM+US) that can be used at finishing and semifinishing modes and EDM with complex kinematics - “milling EDM”. The rotary movement of the electrode-tool has the advantage that during the discharge duration, the energy is dissipated over the machined surface, and thus it and be levelled, i.e. the roughness is decreased, but the disadvantage of the instability of EDM process that is increased - often short-circuits between the tool and the workpiece. The ultrasonic vibration of the tool has the capacity to increase the stability of the removal process and hence the output EDM technological parameters. The paper presents the construction of the rotary head in two variants. The first one is more compact and more compatible to be used on CNC machining. The second one has an airier construction, which allows a better cooling of the ultrasonic transducer zone, susceptible to be overheated during EDM process.
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