Self-erecting folding fin

Claim 1

A SELF-ERECTING STRUCTURE, COMPRISING, A SPAR, A FIRST HINGE PIN MEANS RIGIDLY CONNECTED TO SAID PAIR AND EXTENDING WITH ITS LONGITUDINAL AXIS PERPENDICULAR TO THE LONGITUDINAL AXIS OF SAID SPAR, SAID FIRST HINGE PIN MEANS HAVING A COLLAR AT ONE END THEREOF, A BEARING MOUNTED ON SAID HINGE PIN MEANS, AN ERECTABLE MEMBER MOUNTED ON SAID SPAR AND BEING PIVOTABLE ABOUT THE LONGITUDINAL AXIS OF SAID FIRST HINGE PIN MEANS FROM A FOLDED POSITION TO AN ERECTED POSITION ON SAID SPAR, AN AERODYNAMICALLY SMOOTH HOUSING ON SAID MEMBER COVERING SAID BEARING, SAID HINGER PIN MEANS, AND SAID COLLAR, PLUG MEANS COVERING ONE END OF SAID HOUSING, TORSION SPRING MEANS WITHIN SAID HOUSING AND CONNECTED AT ONE END TO SAID PLUG, AND AT ITS OTHER END TO SAID COLLAR, SAID TORSION SPRING MEANS URGING SAID MEMBER INTO SAID ERECTED POSITION, LATCH PIN MEANS SLIDABLY MOUNTED WITHIN SAID SPAR ALONG ITS LONGITUDINAL AXIS, SPRING MEANS MOUNTED IN SAID SPAR FOR URGING SAID LATCH PIN MEANS INTO SAID ERECTABLE MEMBER WHEN SAID MEMBER IS PIVOTED TO SAID ERECTED POSITION, AND A SECOND HINGE PIN MEANS ATTACHED TO SAID ERECTABLE MEMBER AND EXTENDING PERPENDICULAR TO THE LONGITUDINAL AXIS OF SAID SPAR, SAID ERECTABLE MEMBER BEING PIVOTABLE ABOUT THE LONGITUDINAL AXES OF SAID SECOND HINGE PIN MEANS, SAID SECOND HINGE PIN MEANS ENGAGING SAID LATCH PIN MEANS TO RESTRAIN SAID LATCH PIN M EANS AGAINST THE URGING OF SAID SPRING MEANS UNTIL SAID ERECTABLE MEMBER IS PIVOTED TO SAID ERECTED POSITION.