Extrusion and building structures

Claim 1

A window-like structure comprising: a plurality of rigid side and end members secured together in perpendicular and parallel relationship to form a frame and arranged to be secured to a building structure, the ends of said members being mitered and united together, each of said members of said frame being formed with a first channel which combine to form a continuous channel positioned around the periphery of said frame, said channel including teeth projecting inwardly from its sides; a sheet of flexible plastic material spreading over all of said side and end members; a plurality of locking members being inserted in said continuous channel, thereby forcing a portion of said flexible plastic sheet into said channel and stretching, sealing, holding, and locking said sheet to said frame in said channel; each said locking member being formed as a one piece extrusion having a generally T-shape in cross section with a stem and a head both of which are formed of substantially rigid plastic material and which has both sides of the stem of the T provided with integral spaced angularly and outwardly extending projections of plastic material substantially more flexible than the substantially rigid material of the main section of the T and integrally united with the substantially rigid material of the main section of the T, said projections having a thickness less than the stem and being inclined from the stem toward the head; the width of the channel between the crests of the teeth being less than the width between the outer ends of the projections, the teeth and projections combining to lock the sheet in place, the improvement comprising: means forming a second channel in the side and end members, said second channel being spaced inwardly from the first channel and designed to receive a resilient spline, a sheet of screen material extending over the frame and the second channel and being locked in said second channel by the spline.