Expandable Shaft

An expandable shaft comprising:

• a substantially cylindrical central body having at least one groove formed on its outer surface in a direction substantially parallel to its longitudinal extension axis (X);
• at least one substantially rod-shaped slat arranged within said groove and configured to translate in a direction substantially radial to said axis (X) from a retracted position to an expanded position and vice versa, said slat being configured to have in said expanded position its upper surface projecting with respect to the cylindrical surface of said central body;
• at least one inner tube interposed between the bottom of said groove and said slat, said inner tube being configured to translate said slat from said retracted position to said expanded position;
• wherein said central body has at least one first recess and at least one opposite second recess formed at the side edges of said groove, said slat having at least one trough formed on said upper surface over the entire width of said slat and configured to be aligned with said first recess and said second recess, said expandable shaft comprising holding means arranged within said trough and with their ends inserted within said first recess and said second recess so as to block the translation of said slat from said retracted position to said expanded position.