Strutless umbrella frame for supporting a canopy

A strutless umbrella frame arranged for supporting a canopy, the strutless umbrella frame being operable between a closed and an open position, the umbrella frame comprising:

• a central post;
• a plurality of ribs each pivotally mounted to the central post about a pivot axis, the plurality of ribs arranged for being retracted when the umbrella frame is in the closed position and for being extended when the umbrella frame is in the open position;
• an actuator disposed within the central post arranged for operating the umbrella frame between the closed and open position;
• and
• a connection arranged for hingendly connecting each of the plurality of ribs to the actuator such that a force generated by the pivoting movement of the at least one of the ribs is transferred to the actuator;
• the actuator comprises:
• at least one air spring comprising a piston rod connected at one end to the connection and to the other end on the outer surface of a piston, which piston is reciprocably movable within a fluid tight cylinder barrel in response to an opening and a closing force applied by pivoting movement of the at least one of the ribs, the piston being arranged for dividing the interior of the cylinder barrel into a first and a second fluid chambers, wherein the cylinder barrel defines a first and a second pressure zone;
• a first fluid regulator arranged for allowing fluid to flow between the first and second fluid chambers when the piston is positioned along the first pressure zone;
• and
• a second fluid regulator arranged for allowing fluid to flow between the first and second fluid chambers when the piston is positioned in the second pressure zone, which second fluid regulator is arranged for being activated in response to the pressure in the first or second chamber reaching a predetermined threshold due to an external force applied on the piston by the pivoting movement of at least one of the ribs;
• wherein the actuator is arranged for:
• opening the umbrella, when the plurality of ribs are retracted, in response to a predetermined opening force applied initially by the pivoting movement of at least one of ribs, and
• for closing the umbrella, when the plurality of ribs are extended, in response to a predetermined closing force applied initially by the pivoting movement of the at least one of the ribs.