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Claim 1

A WINDOW ASSEMBLY COMPRISING A WINDOW FRAME HAVING A SPACED LOWER AND UPPER PAIR OF MEMBERS INTERCONNECTED BY A PAIR OF SPACED SIDE MEMBERS TO DEFINE A WINDOW OPENING, A WINDOW UNIT AND MEANS FOR MOUNTING SAID WINDOW UNIT TO SAID FRAME SELECTIVELY TO OPEN AND CLOSE THE OPENING, SAID WINDOW UNIT, IN AN OPEN POSITION, BEING REMOVED FROM THE PLANE OF THE WINDOW OPENING, SAID MOUNTING MEANS COMPRISING AN ELONGATED TORSION SPRING HAVING AN ARM SECURED THERETO AND PROJECTING THEREFROM TO BE DISPOSED AT AN ANGLE CORRESPONDING TO THE ANGLE BETWEEN THE LOWER MEMBER OF THE FRAME AND AN ASSOCIATED ADJACENT SIDE MEMBER, MEANS SECURING SAID TORSION SPRING TO THE LOWER MEMBER INCLUDING RESTRAINING MEANS AND JOURNAL MEANS DISPOSED IN SPACED RELATION ALONG THE LENGTH OF SAID TORSION SPRING, SAID JOURNAL MEANS PREVENTING RELATIVE MOVEMENT OF SAID LOWER MEMBER AND TORSION SPRING EXCEPT ABOUT THE LONGITUDINAL AXIS OF THE TORSION SPRING AND MEANS PIVOTALLY SECURING THE FREE END OF THE ARM TO THE WINDOW UNIT ADJACENT A MARGINAL EDGE THEREOF TO PIVOT ONLY ABOUT AN AXIS PARALLEL TO THE LONGITUDINAL AXIS OF THE TORSION SPRING.