Highway guard fence

Claim 1

A GUARD FENCE FOR USE ON A HIGHWAY, COMPRISING: A PLURALITY OF FOUNDATIONS SPACED ALONG A CURB OF THE HIGHWAY; A PLURALITY OF TWO-DIMENSIONAL FRAMES; ATTACHMENT MEANS TO MOUNT ONE OF SAID FRAMES ON EACH OF SAID FOUNDATIONS TIGHTLY SECURED THERETO IN UPRIGHT POSITION TO EXECUTE A RIGID-BODY ROTATIONAL MOVEMENT ABOUT AXES EXTENDING APPROXIMATELY PERPENDICULAR TO THE RUN OF THE HIGHWAY AT THE POINTS OF MOUNTING, WHEN THE TORQUE EXERTED BY AN IMPACTING VEHICLE ABOUT THESE AXES REACHES A MINIMUM VALUE; EACH OF SAID FRAMES ATTACHED TO ITS FOUNDATION AT TWO POINTS LYING ON A LINE EXTENDING APPROXIMATELY PERPENDICULAR TO THE RUN OF THE HIGHWAY; SAID POINTS SEPARATED A DISTANCE SUFFICIENT TO ENABLE THE FRAMES TO WITHSTAND LARGE TORQUES ABOUT AXES APPROXIMATELY PARALLEL TO THE RUN OF THE HIGHWAY, SAID TORQUES CALCULATED UPON THE MAXIMUM EXPECTED WEIGHTS AND IMPACT SPEEDS OF THE VEHICLES USING THE HIGHWAY; A PLURALITY OF CABLE HOLDING MEANS SPACED ON EACH OF SAID FRAMES FOR RELEASABLY HOLDING CABLES TO SAID FRAMES; AND A PLURALITY OF CABLES TAUTLY STRETCHED APPROXIMATELY PARALLEL TO THE HIGHWAY FROM FRAME TO FRAME AND EACH HELD AT EACH OF SAID FRAMES BY ONE OF SAID HOLDING MEANS, SAID ATTACHMENT MEANS COMPRISING: PAIRS OF JOURNAL BEARINGS, ONE FOR EACH FRAME; ONE PAIR RIGIDLY MOUNTED ON EACH OF SAID FOUNDATIONS; SAID FRAMES BEING PIVOTABLE IN SAID PAIRS OF BEARINGS; AND ROD MEANS FOR EACH FRAME TO HOLD EACH FRAME IN THE UPRIGHT POSITION AND TO RELEASE EACH FRAME FOR PIVOTING WHEN STRUCK BY A VEHICLE.