Removable sash window construction

Claim 1

AN AUTOMATICALLY-LOCKING RESILIENTLY-BALANCED TILTABLE WINDOW SASH CONSTRUCTION ADAPTED TO BE INSTALLED IN A WINDOW FRAME, SAID CONSTRUCTION COMPRISING A PAIR OF ELONGATED VERTICAL SASH GUIDES ADAPTED TO BE MOUNTED ON OPPOSITE SIDES OF THE WINDOW FRAME, AT LEAST ONE OF SAID SASH GUIDES BEING ADAPTED TO BE RESILIENTLY MOUNTED ON ONE SIDE OF THE WINDOW FRAME, A SASH UNIT MOVABLY MOUNTED ON SAID SASH GUIDES FOR VERTICAL SLIDING MOTION RELATIVELY THERETO, SAID SASH UNIT HAVING COUPLING-ENGAGING PORTIONS THEREON DISPOSED ADJACENT SAID SASH GUIDES, EACH OF SAID SASH GUIDES INCLUDING A HOLLOW SASH BALANCE CASING PORTION WITH VERTICAL WALLS, ONE OF SAID WALLS HAVING AN ELONGATED SLOT THEREIN WITH FLANGE-LIKE ELONGATED VERTICAL WALL PORTIONS DISPOSED ON OPPOSITE SIDES OF SAID SLOT, A RESILIENT SASH-BALANCING MEMBER MOUNTED WITHIN EACH SAID CASING PORTION AND HAVING ONE END PORTION ANCHORED THERETO, A LOCK CARRIER SLIDABLY MOUNTED IN EACH SAID CASING PORTION AND CONNECTED TO THE OPPOSITE END PORTION OF EACH SAID SASH BALANCING MEMBER, A LOCKING MEMBER ROTATABLY MOUNTED ON EACH SAID LOCK CARRIER WITH ITS AXIS OF ROTATION DISPOSED SUBSTANTIALLY PERPENDICULAR TO THE SLOTTED CASING WALL AND MOVABLE INTO AND OUT OF LOCKING ENGAGEMENT WITH ONE OF SAID WALLS OF SAID CASING PORTION, EACH LOCKING MEMBER HAVING A COUPLING PORTION PROJECTING THEREFROM THROUGH ITS RESPECTIVE SLOT INTO ONE OF SAID COUPLING-ENGAGING PORTIONS OF SAID SASH UNIT, AND MEANS RESPONSIVE TO THE ROTATION OF SAID LOCKING MEMBERS BY TILTING OF THE SASH UNIT RELATIVELY TO THE SASH GUIDES FOR TOTATING SAID LOCKING MEMBERS AND CONSEQUENTLY THRUSTING SAID LOCK CARRIERS INTO LOCKING ENGAGEMENT WITH THEIR RESPECTIVE CASING PORTION WALLS.