Precision Machining for Adapter Manufacture

Precision requirements are particularly high in the printed circuit board industry. Multi-layer boards, for instance, must be drilled down to exactly the right depth to ensure vertical interconnect access (via). The drill hole diameter must be as small as 0.1 mm and the drilling depth in the order of micrometres. This calls for low-vibration machine concepts, high-precision drive elements, accurate tool measurements, including a correction option, and continuous monitoring of the parameters. Especially in depth drilling, one unknown factor plays an important role: the varying height of workpieces. The clamped workpiece may show height tolerances which even the most precise machines cannot compensate or, if so, only using complex and time-consuming measuring methods.

Anderson has developed a reliable and fast system especially designed for depth drilling which is integrated into the fully automatic manufacturing processes. Variable-pressure downholders with an integrated differential measurement system ensure that the actual workpiece height is measured prior to every drilling operation. The actual height is redetermined every time as a reference value, which is taken into consideration by the machining programme. In our opinion this is as precise and practicable as one can get.