Machine Design

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MACHINE DESIGN
Even in the early development stage, the dynamic machine response has been constantly evaluated. A direct coupling between the 3-D CAD model and an analysing program using the finite elements method was established. This ensured that the dynamic rigidity and machine response are optimally designed. The static and dynamic dimensional stability of the NANO FOCUS machine is essential for a perfect and precise process result. The base frame of the NANO FOCUS consist of a stiff granite portal. It weighs more than 12 tons and serves as reference for the turning- and swiveling table and the slide groups. The advantages of a granite base:

• Good damping properties
• High thermal stability
• High static and dynamic stiffness
• Free of stress
• Corrosion free

Thermal stability is ensured by using a temperature stabilization system. This system keeps the essential machine components, such as base frame, milling spindle, linear motors, torque motors and the oil at a constantly controlled temperature. Thus ensuring low thermal deviations, resulting in a high predictable process quality.  A system of special dampers is assembled between the base frame and the setup location. These dampers insulate the machine against environmental vibrations of more than 7 Hz significantly decrease or completely damp out. An additional traverse in X-direction (400 mm) towards the operator gives excellent accessibility for inspection and for loading and unloading of components. The NANO FOCUS ultra precision machine is also shielded by a full room enclosure with fume extraction. The entire work area is secured electronically and the operator is completely protected from chips and coolants. This fulfills several logical requirements: accessibility, safety and the view of the component and tools during the milling process. The horizontal NANO FOCUS ultra precision machine weighs more then 15 tons overall and can be set up on a standard floor plate due to special dampers! 
 
ROTARY / SWIVEL TABLE
The large dimensioned rotary / swivel table has an outstanding "compact" design. The static, dynamic and thermal stability of the design and the use of an unconventionally light, stiff and strong material makes this rotary / swivel table a unique machine element. The absolute quality of complicated and precise components can only be achieved through the extremely high positioning and repeatable accuracy, which is very important for the 5-axes simultaneous processing.  The accuracy of the two rotation axes in combination with the additional linear axes is of the highest quality through which the best surface qualities can be achieved.The precision achieved by the two rotation axes, combined with the remaining linear axes, is of very high quality with which the dimensional and shape accuracy (< 5  µm) and surface finish quality (Ra 0,2 µm) can be achieved on a hardened component.


HYDROSTATIC SLIDES AND GUIDEWAYS
All linear axes (X, Y and Z axes) and rotation axes (A and B axes) run in “frictionless” constructed hydrostatic “wear-resistant” guides and therefore achieve the extremely high positioning and repeatability accuracy of ± 0.1 µm. All axes are powered by the most modern linear and torque motors. It is apparent that the spindle bearings and spindle guides are one of the most important elements of the machine in regards to the lifetime of the machine and the ultra precision of the components to be produced. The hydrostatic guide system of the NANO FOCUS ultra precision machine exceeds by far, the features of the conventional systems.
The NANO FOCUS ultra precision machine offers the future users the benefits of excellent stability and reliability combined with the highest precision and the additional frictional resistance and therefore an unlimited lifetime with the use of the hydrostatic concept for such important machine elements.




LINEAR AND TORQUE MOTORS
This technology guarantees the highest dynamics, speed and precision in conjunction with the rapid control and regulating system. All linear axes (X, Y, and Z axes) are equipped with linear motors. The two rotation axes (B and C axes) are equipped with torque motors. Since all axes have direct drive, it goes without saying that the drive system of the NANO FOCUS ultra precision machine has zero backlash. Because there is no metal-to-metal contact in the hydrostatic system, it is free of friction and wear, as well as precise and easy to maintain.

TOOL CHANGER
The NANO FOCUS ultra precision machines are equipped with a reliable fully automatic tool changer. Tool taper HSK 40 E, according to DIN 69863 is used in the spindle nose. The tool changer offers 28 pockets and a maximum number of 90 pockets (option).

SIEMENS CONTROL UNIT
The Siemens 840 D is a PC based control unit equipped with the most modern technology and a Windows user interface. The SIEMENS 840 D control unit also guarantees precise and quick data processing.  The Siemens 840 D is equipped with a resolution of 0.01 µm.