Abstract: A device for harvesting bilberries comprises: a frame including a handgrip portion; a shaking unit, including a hook-shaped portion for grasping a branch of a bilberry plant, wherein the shaking unit is movable relative to the frame with reciprocating motion along an axis of vibration to shake the branch; a motor; a transmission unit, wherein the motor is associated with the transmission unit to vibrate the shaking unit along the axis of vibration at a variable vibrating frequency; a frequency adjustment system drivable by the operator to select the vibration frequency at least between a first frequency and a second frequency, wherein the frequency adjustment system is configured to keep the vibration frequency permanently set at the setting selected by the operator.

Abstract: A screw compressor has an electric motor having a first output shaft; and two intermeshing rotors, one of which has a second output shaft substantially coaxial with the first output shaft; the first and the second output shaft being connected directly by a conical coupling.