Hatch cover

Claim 1

A FLUSH DECK HATCH OR MANHOLE CONSTRUCTION HAVING A COVER WITH LOCKING AND CLAMPING MEANS WHICH IS OPERABLE FROM BOTH INSIDE AND OUTSIDE, SAID CONSTRUCTIN COMPRISING A SUPPORTING RING HAVING A CONTINUOUS INWARDLY DIRECTED HORIZONTAL FLANGE AND A VERTICAL WALL EXTENDING UPWARD FROM THE OUTER EDGE OF SAID FLANGE, A COVER PLATE HAVING A PERIPHERAL GASKET GROOVE IN ITS UNDER SIDE, A RESILIENT GASKET RING MOUNTED IN SAID GROOVE AND PROJECTING BELOW SAID UNDER SIDE OF THE COVER PLATE TO SUPPORT THE COVER PLATE ON SAID FLANGE, A CENTRAL BOLT PROJECTING THROUGH A SMOOTH BORE HOLE IN SAID COVER, A HEAD ON SAID BOLT RECESSED IN THE UPPER SIDE OF SAID COVER, WRENCH ENGAGING MEANS IN SAID HEAD FOR TURNING THE BOLT FROM THE UPPER SIDE OF THE COVER, A WASHR AND A GASKET ON SAID BOLT UNDER SAID HEAD, A LOCKING BAR HAVING THREADED ENGAGEMENT WITH SAID BOLT ON THE UNDER SIDE OF SAID COVER, A TRANSVERSE HANDLE BAR ON THE LOWER END OF SAID BOLT FOR TURNING THE BOLT BETWEEN SAID LOCKING BAR AND SAID SPRING ON SAID BOLT BETWEEN SAID LOCKING BAR AND SAID HANDLE BAR TO INCREASE THE FRICTIONAL ROTATIVE DRAG BETWEEN SAID LOCKING BAR AND BOLT, SAID LOCKING BAR BEING ROTATABLE WITH SAID BOLT BETWEEN LOCKED AND UNLOCKED POSITIONS, STOPS ON SAID COVER ON OPPOSITE SIDES OF SAID LOCKING BAR LIMITING ROTATION OF SAID LOCKING BAR RELATIVE TO SAID COVER, SAID LOCKING BAR IN LOCKED POSITION HAVING ITS OPPOSITE ENDS UNDERLYING PORTIONS OF SAID FLANGE AND IN UNLOCKED POSITION HAVING SAID ENDS CLEARING SAID FLANGE SO THAT THE LOCKING BAR WILL PASS THROUGH THE SUPPORTING RING WITH THE COVER WHEN THE COVER IS LIFTED, SAID BOLT BEING ROTATABLE IN SAID LOCKING BAR TO CLAMP SAID COVER AND COMPRESS SAID GASKET.