Energyharvesting device The present invention relates to a very simple and robust wireless batteryless device (100) for harvesting energy. The actuation upon button pressure/release results in a rotation of a first member (1) around its central axis (11) leading to a move of an element (3), which is loosely fixed at the first member (1) from a pivot point (14), and a rotation around the central axis (11) of the second member (2) to which a generator axis of an energy harvester is coupled, the rotation axis of the generator being coincident with the central axis (11). Upon full pressure/release, the element (3) is forced to rotate around the pivot point (14), allowing a vertically raised pin (22) of the second member (2) to disengage a recessed area (31, 32) at each end of a slot (30) of the element (3) and the second member (2) to rotate to its rest position.