Sliding sash window assembly

A sliding sash window assembly comprising, in combination, a rectangular window frame having respective upper and lower frame header and sill members interjoined at their ends with opposed, parallel side frame members, a plurality of rectangular window sashes, means slidingly interconnecting said sashes in said window frame for relative sliding up and down movement therein, said interconnecting means comprising frictional contact means between said sashes and said frame for frictionally retaining said sashes in adjusted vertical positions in said frame, said frictional contact means comprising T-shaped grooves formed along the insides of said side frame members, a plurality of synthetic plastic slide members, said slide members being formed along their lengths with a substantially rectangular portion of uniform cross-sectional shape receivable within said T-shaped grooves for up and down sliding movement therealong, opposed outer side portions of said slide members being formed therealong with end-to-end recesses, said T-shaped grooves being defined by opposed inwardly-projecting portions receivable in said recesses, said slide members being hollow from end-to-end along their length, and compression spring means within said slide members for yieldingly constraining opposed outer surface portions of said substantially rectangular portion of said slide members against opposed inner wall portions of said frame members defining said T-shaped grooves, said substantially rectangular portions of said slide members being slotted along their outsides to open into the hollow interior thereof, said spring means comprising a U-shaped compression spring fitted within each end of said slide members so as to resiliently urge said opposed outer surface portions of said slide members in relatively outward directions.