This is where the new spindle speed increasers can be applied; they are much smaller and weigh substantially less than a typical machine spindle. The largest turbine assembly in the new BIG KAISER RBX line has an effective diameter of just 75 mm. The entire speeder weighs just 5 kg. The light weight RBX allows operators to focus on the dynamic run-out and balance issue that makes high-speed micro machining difficult.
The BIG KAISER air-powered spindles at to be shown MACH 2016 use compressed air to drive a turbine and develop much higher spindle speeds than a conventional machine spindle. An instant benefit is that the machine spindle doesn’t rotate when running a speeder, so it incurs no wear and tear. Furthermore, the use of air pressure as an energy source eliminates problems associated with the heat generated when a machine tool spindle runs near its maximum speed for prolonged periods.
One essential factor users should keep in mind when considering an RBX spindle is that when output speed increases, available torque decreases. The RBX5 covers spindle speeds from 40,000 to 50,000 rpm for drills and endmills up to 1.5 mm diameter; the RBX7 handles the 60,000 to 80,000 rpm range and the RBX12 delivers spindle speeds from 100,000 to 120,000 rpm for end mills of 0.6 mm diameter or less and drills of 0.4 mm or less.
The maximum required air pressure to achieve the top speed in any range is 90 psi.
BIG KAISER has integrated its air-turbine drive mechanisms directly into a proven high-speed tool-holding solution, a micro-collet that clamps tool shanks with diameters as small as 0.5 mm. The run-out achieved by this is 3 micron at four times tool diameter and is said to increase tool life and improve finish compared to a conventional collet system.
