Charmilles (www.charmillesus.com) says its new Roboform 350 MicroTEC die sinking EDM offers innovations in precision, speed and productivity for small die and mold applications. The EDM integrates new discharge circuitry with the company's double thermostabilization system, DPControl and Expert Systems.
The discharge circuitry enables EDM power to be modulated with the flexibility necessary to maximize material removal while allowing a reduced electrode undersize of 0.002 in. Charmilles says this allows for higher machining outputs while maintaining the geometry of the electrodes due to an extremely low wear rate.
The double thermostabilization system is a world first in preventing the impact of temperature variations for maximum accuracy, according to Charmilles. Pulsed air circulating in the cabin is cooled in real time according to the temperature of the dielectric by a double-differential temperature probe. The whole of the main frame and the X, Y and Z axes are thermostabilized. Circulation of the dielectric is integrated into the work table to prevent thermal shocks while the tank is being filled.
The DPControl will suggest to the operator the ideal electrode undersize and will rationalize the number of electrodes necessary for effective machining. The control allows direct access to measurements performed on a preset station and allows for organization of jobs according to the users' priorities.
It allows for monitoring with the automated production features of Expert Systems, and all information related to machining status can be transmitted directly to the operator via SMS (cell phone text messaging). The control also evaluates a completed job by automatically creating a full report on job execution readily accessible to the operator via the network or directly on the machine
The EDM features Accura-C, a high-precision C-axis that provides an increase in positioning accuracy down to 3.6 arc seconds. To counteract the effects of pulsation movements in the dielectric fluid and increase stability, the C-axis is built to withstand inertia of up to 1,708 lbs/in 2 . This allows machining with electrodes weighing to 110 lbs. Accura-C features a liquid cooling system to eliminate inaccuracy from thermal instability.
The optional rotary tool changer can store as many as 160 electrodes that vary from one cavity to another. A double gripper is used that allows change from electrode to electrode in less than 60 seconds.