Servo gear units

The re-engineered PSF series of planetary gear units and new BSF series of helical-bevel gear units are minimal-backlash servo gear units developed by SEW-Eurodrive. They are claimed to offer superior torque handling for a given model size and are precision-engineered to maximise power transmission efficiency.

The servo gear units are available with multiple output shaft configurations, including a 'flange block shaft' arrangement. The flange block shaft gear units (PSBF and BSBF models) feature a rotating flange that enables the load to be bolted directly to the gearbox, obviating the need for a coupling. This development significantly reduces backlash, a primary criterion for precision servo positioning systems. Other gear unit output shaft arrangements within the range include solid shaft with/without key (PSF and BSF models) and a hollow shaft arrangement in the angular helical-bevel gear unit range (BSHF model).

Another feature of the SEW-Eurodrive servo gear unit range is the high overload capacity achieved by exactly matched components, allowing high torque transfer and the absorption of large axial and radial forces. This means the gearboxes can be accelerated faster, for example, in belt drive systems and rack and pinion applications.

The PSF and BSF servo gear units are compact and lightweight. The planetary gear unit with solid shaft (PSF) range is available in nine different models from 25 to 3000 Nm output torque, the planetary gear unit with flange block shaft (PSBF) range has six models from 55 to 1750 Nm, while the helical-bevel gear unit ranges (BSF, BSBF, BSHF) have six models each from 40 to 1500 Nm. All models exhibit high overload capacity of up to 400%.