High-speed machining technology has progressed rapidly over the last few years and is ready to take on the task of using high-RPM spindles, extremely accurate linear motor servo drive systems, direct drive rotary axes, high-speed machine controllers, and advanced cutting tool coatings. Roku-Roku, a specialty machine tool builder known for making high-quality, extremely accurate machines, has researched and incorporated all of these technologies into the ANDROID II 5AXP-DD model. The ANDROID II 5AXP-DD is a machining center designed from the ground up for extremely precise, hard-steel machining at high spindle speeds and high traverse rates: true “high-velocity” machining.
The Roku-Roku ANDROID II 5AXP-DD is an exceptionally well-built machine tool coupled with the Fanuc 31i-B5 CNC controller. Roku-Roku’s Super PC III optimizes velocity and acceleration/deceleration through the use of a super high-speed processor and AI Contour Control II, high-speed processing, Nano smoothing, and look-ahead block expansion. The combination of high-speed calculation and read-ahead control minimizes geometric errors during high-speed contouring of continuous small motion commands. Super PC III can be set to one of three different modes to meet your machining requirements. The Roku-Roku ANDROID II 5AXP-DD also features Fanuc’s Digital Intelligent Servo System with five-decimal-place input and feedback. This combination results in unsurpassed speed and accuracy, even in the most complex 3D contours consisting of short, consecutive line segments or arcs.
The Roku-Roku ANDROID II 5AXP-DD is designed around a thermally symmetrical frame. The casting/frame maintains its machine posture against environmental change in temperature. A symmetrical frame is required for stable repeatability. The optimum structure is implemented by finite element analysis for casting parts. Minimum displacement is implemented by structural CAD simulation analysis. The rib structure for cross rail with micro-fine machining center design has a three-layer hollow structure that is efficiently achieved with forced ventilation.
The ANDROID II 5AXP-DD uses a 60,000-RPM spindle. Without sufficient spindle RPM, it would be impossible to machine hardened steel efficiently. High RPM enables an operator to maintain chip load and depth of cut while increasing feed rate. The result is a larger volume of stock removal in less time than conventional machining methods. This method of machining also produces superior surface finishes, resulting in less polishing time. It is a proven method of machining that increases productivity in all aspects of machining (i.e., surface milling, side milling, drilling, etc.).
The Roku-Roku ANDROID II 5AXP-DD uses a pair of horizontally opposed linear drive motors mounted in each of the X-, Y-, and Z-axis. This design offsets the magnetic force between the motors and minimizes the uneven load on the guides and moving parts a single linear motor creates. Double cooling channels are incorporated to ensure that any coil-generated heat does not affect machining accuracy. Special precision roller-type linear motion ways are used on all axes, increasing the contact point by 6 times compared to ball-type LM guides. This increased contact area improves machine rigidity, providing smooth motion for high-precision accuracy. Elongation of the carriage and expanding the supporting width of the casting have also improved the straightness of the cut. An active heat isolation system has been implemented on the ANDROID II 5AXP-DD, providing full thermal control of the machine in accordance with room temperature. The system provides coolant thermal control through double-jacketing the spindle housing with a spindle oil cooler and cooling through the Z-axis casting. Other heat sources such as the linear motor coils and control cabinet have been heat isolated and thermally controlled by chiller coolant or forced-air circulation.
The ANDROID II 5AXP-DD has been integrated with a Tsudakoma direct drive 2-axis high-precision table with a 5.9” (150mm) diameter faceplate, turning the ANDROID II into a full 5-axis simultaneous micro-accuracy machining center. The Fanuc control has the NC option package for 5-axis machining for full 5-axis program operation.
