Updated 30-taper mill-turn centre encourages high accuracy cutting

Improvements include an integrated, high output, direct drive motor in the C-axis to replace the previous roller drive powering the 2,000rpm turning table. The A-axis trunnion rotates through a 50% larger angle, from 120 to -30°, allowing machining of features at the rear of components and facilitating loading and unloading of parts at the front of the machine.

Furthermore, the A-axis is now tilted by a backlash-free roller drive, promoting high accuracy metal cutting. A holding force of 400Nm without the need for a mechanical clamping mechanism delivers high speed indexing combined with rigidity when milling parts at an angle or turning them in the horizontal plane.

A new option is a 16,000rpm BIG Plus face-and-taper contact spindle, which can be specified in place of the standard 10,000rpm spindle. X/Y/Z travels of 200, 440, 305mm remain the same, but the distance between the table surface and the spindle nose has been increased to 455mm, providing more space for the fixture, workpiece and cutting tool and hence extending versatility of production.

Brother has removed every conceivable element of non-productive time. For example, not only are speeds fast during non-cutting motions, but they also take place simultaneously in X, Y, Z, A and C, together with tool change. The spindle motor's rapid acc/dec and a highly responsive servo control enable a 0.2s start/stop time. Start-up time of the turning table from 0-2,000rpm is less than 0.3s.

The specification of the Speedio M140X2 includes 0.9s tool change from the 22-position magazine, giving 1.4s chip-to-chip time. Rapids of 50m/min in the linear axes help to minimise non-cutting times further, while 30m/min cutting feed rate maximises metal removal rate. Synchronised tapping is world-leading at 377m/min peripheral tap speed.

Accessibility for workpiece transfer is ergonomic and the door opening can be automated for high production environments or to automate load/unload. Swarf management measures are comprehensive, as befits a machine that is likely to handle large volumes of aluminium chips. A new, high speed C-00 control system completes the package.