Patent ID: 7980262

Claim:
A windproof umbrella comprising: a center post ( 10 ) comprising an upper grommet ( 11 ), an intermediate fixed ring ( 12 ), and a lower sliding runner ( 13 ); a plurality of ribs ( 20 ) each having one end ( 21 ) pivotably secured to the grommet ( 11 ) and an other, open end ( 22 ); a plurality of main joints ( 51 ) each formed at a portion of the rib ( 20 ) proximate to the other end ( 22 ); a plurality of stretchers ( 30 ) each having one end ( 31 ) pivotably secured to the ring ( 12 ) and the other end ( 32 ) slidably and pivotally secured to the main joint ( 51 ); a plurality of auxiliary joints ( 61 ) each formed at a portion of the stretcher ( 30 ); and a plurality of struts ( 40 ) each having an one end ( 41 ) pivotably secured to the runner ( 13 ) and an other end ( 42 ) moveably secured to the auxiliary joint ( 61 ); a lower canopy ( 70 ) secured in covering relation on the ribs ( 20 ); and an upper canopy ( 80 ) having a center secured to the grommet ( 11 ) and an outer peripheral edge positioned over a portion of the lower canopy ( 70 ) in covering relation to all of the main joints ( 51 ), wherein wind caught beneath the canopies ( 70 , 80 ) applies pressure to the canopies ( 70 , 80 ) to cause a portion of the upper canopy ( 80 ) to lift away from a portion of the lower canopy ( 70 ) to form a plurality pairs of communicating inner and outer vent holes ( 71 , 81 ) with the other ends ( 32 ) of the stretchers ( 30 ) sliding away from the center post ( 10 ), each pair of the inner and outer vent holes ( 71 , 81 ) being defined by the portions of the upper and lower canopies ( 70 , 80 ), the adjacent ribs ( 20 ), and the adjacent main joints ( 51 ).