Drilling and milling machine F205-V with ball screws and a German motor

The F205-V drilling and milling machine offers a wide range of applications. The machine is driven by a frequency-controlled three-phase asynchronous motor. Thanks to its two-stage gearbox, it has two speed ranges (slow and fast), which can be adjusted via a rotary knob. The reduction gear ensures high torque at the work spindle even in the low-speed range. The spindle speed is infinitely variable from 150 to 2,250 rpm. The machine features both clockwise and anti-clockwise rotation. The milling head (Z-axis) is moved using a handwheel. Furthermore, the machine features a fine feed mechanism, which can be used to move only the quill in the Z-direction. For drilling operations, the quill is fed using the star handle on the side. The quill travel is indicated on the digital drilling depth display. The work spindle is fitted with an MK2 tool holder. The dovetail guides on the X, Y and Z axes can be adjusted without play using wedge strips. For clamping workpieces or clamping devices, the 500 x 180 mm work table is fitted with three T-slots (12 mm / M10). The work table is adjusted along the X and Y axes using handwheels with vernier scales. To ensure backlash-free and precise movement, the F205-V’s cross slide is fitted with ball screws.

In a ball screw, also known as a ball-screw drive, balls embedded in the nut transmit the force between the spindle and the nut. As the spindle rotates, these balls move axially in the raceways between the nut and the spindle. The balls are returned via channels in the spindle nut, creating a circuit in which the balls circulate around the spindle.

• The advantages of a ball screw:
• Significantly lower friction (rolling friction) compared to conventional trapezoidal screws (sliding friction)
• Less wear, resulting in a longer service life
• Significantly higher accuracy and zero backlash compared to standard threaded drives such as trapezoidal lead screws
• Higher travel speeds possible