Molded Screen Frame

Abstract

A one-piece plastic molded window screen frame comprises a bead-carrying locking flap which is connected by an integral hinge to a grooved base portion. The edge of the screen panel is firmly but removably retained between the interlocking bead and groove. The frame also has integral tabs which engage grooves in the window opening to retain the frame therein.

Parent Case Text

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of my earlier application Ser. No. 77,624, filed about Oct. 2, 1970 now abandoned.

Description

BACKGROUND OF INVENTION

In recent years attention has been given to forming frames for window screen panels out of one piece of molded plastic. One such method has been to mold the plastic frame around the edges of the screen panel, so that the screen panel edge is permanently embedded and retained in the frame as a result of the molding operation.

The present invention is directed to an improved one-piece molded plastic screen frame, which permits the screen panel to be quickly and easily assembled to the frame, but which permits removal and replacement of the screen panel when necessary.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a small scale elevation of an assembled screen panel and frame.

FIG. 2 is an enlarged fragmentary view of the lower left corner of the frame of FIG. 1, but showing the parts in their open as-molded position which they occupy prior to assemblying and locking the screen panel thereto.

FIG. 3 is a sectional view in the direction of arrows 3--3 of FIG. 2.

FIG. 4 is an enlarged sectional view (without cross-hatching, for clarity) and partially in phantom, similar to FIG. 3, but showing the locking flap portion of the frame in two sequential positions as it approaches the locking position.

FIG. 5 is a sectional view in the direction of arrows 5--5 of FIG. 1, showing an assembled screen and screen panel and the means for retaining the upper edge of the frame in a window opening.

FIG. 6 is a sectional view similar to FIG. 5, but showing an alternative method for retaining the lower portion of the screen frame in a window sill.

DETAILED DESCRIPTION OF THE INVENTION

The drawings illustrate a molded one-piece plastic rectangular frame 10, generally comprising a base portion 12 and a locking portion 14 connected to base 12 by a thin-walled continuous integral hinge 16. One material which has proven particularly suitable for such a frame is polypropylene, since its properties include adequate flexibility and fatigue resistance for the hinge 16. In a preferred embodiment, the thickness of hinge 16 is approximately 0.015-0.020 inches, and the total width of base 12 is about three-fourths an inch.

FIGS. 2 and 3 show frame 10 in its as-molded and open condition, FIG. 3 being a typical cross-section through any side of the frame. Base 12 has an upper face 18 which is provided with a deep and wide groove 20. Locking flap 14 is provided with a continuous bead 22 which is dimensioned and shaped to compliment groove 20, so that when the edge of screen panel 24 (see FIG. 5) is stuffed into groove 20, the screen panel will be firmly locked between the interlocking bead 22 and the groove 20 of the frame.

The manner in which a firm but releasable clamping of the screen panel is obtained will be best understood by examination of FIG. 4. As locking flap 14 is pivoted towards its closed position, corner 26 of bead 22 makes initial contact with edge 28 of groove 20 in frame base 12. This position is shown in solid lines in FIG. 4. Because of the readily apparent interference between corner 26 and edge 28, it becomes necessary for some portion of the assembly to yield to permit further closing of locking flap 14.

Initially, continued downward pressure on locking flap 14 causes the rounded surface of corner 26 to be cammed to the left by edge 28. To accomplish this, hinge 16 yields toward the left, until shoulder 30 of bead 22 contacts the outer or left side wall of groove 32. Continued downward pressure on locking flap 14 causes continued leftward movement of bead shoulder 30 against groove sidewall 32, causing the upper outer portion of base 12 to yield toward the left. This condition is shown in phantom lines in FIG. 4. Only after the combined yielding of hinge 16 and sidewall 32 can bead 22 complete its entry into groove 20. Once corner 26 is fully past edge 28, the yielded components return to their initial position as the bead snaps into the groove. To release the locking flap, it is necessary for a similar temporary yielding to occur, and it is this temporary deflection which provides the secure locking action. Of course when the frame is closed on a screen panel, additional interference results, requiring additional deflection to complete the closing action. Additional security is provided by the slight degree of softness of the polypropylene material which causes the screen wire to embed itself slightly along the clamping surfaces.

The provision of the yielding outer sidewall 32 of groove 20 functions to reduce the amount of load and strain placed on hinge 16 during opening or closing of the frame, thus reducing the danger of premature failure of the hinge.

One method of retaining frame 10 in a window opening is by the provision of a series of molded integral retention tabs 34 shown in FIGS. 1 and 5. Such tabs are received by grooves 36 formed in the upper portion of window opening 38, while similar grooves can be provided in the lower portion of the window opening. To insert the frame in the window opening, the upper and lower portions of the frame can be momentarily bowed inwardly to permit the tabs to enter the grooves.

FIG. 6 shows an alternative form of retention tab 40, which is also integrally molded with the frame and comprises a hinged member having a locking tab 42 which engages a groove 44 in window sill 46. Retention member 40 is molded in such a way that it has a natural position of approximately 45.degree. to 90.degree. clockwise from the position shown in FIG. 6, so that it has a continuous downward or clockwise bias to retain tab 42 in groove 44. Tab 42 is released by lifting upwardly on the extended portion 48.

While the frame of this invention has been disclosed for use as a window screen frame, it could also be used for storm windows, mirrors, pictures, and so forth. As a storm window, the wire screen mesh would simply be replaced by a polyethylene sheet. In fact, the wire screen could be left in place to serve as additional support for the added polyethylene storm window.

To use the frame for conventional glass storm windows or as a mirror or picture frame, a slight recess would be formed in face 18 of sufficient depth to receive the framed panel. The retained panel would not extend as far outwardly as groove 20, but would be simply retained by the interlock between face 18 and the opposed face of flap 14. All of these alternative applications of the novel frame would employ the concept of the one-piece construction with the integral bead engaging the groove to retain the frame in its closed position, wherein the retained panel is securely held within the frame.

This invention may be further developed within the scope of the following claims. Accordingly, the above specification is to be interpreted as illustrative of only a few operative embodiments of this invention, rather than in a strictly limited sense.

Claims

I now claim:

1. In a hard, substantially non-compressible plastic molded one-piece rectangular peripheral frame for supporting and retaining a panel, wherein each of the sides of the frame comprises a base portion having an upper face provided with a longitudinal groove extending the full length of the respective frame side and parallel thereto, a transverse section through said base being generally U-shaped with a bight defining the bottom of said groove and inner and outer legs defining the sides of said groove;

a locking flap portion integral with said base portion and connected thereto by a continuous hinge portion projecting from the upper outer edge of said base outer leg, said flap porting being pivotally movable about said hinge between a first position wherein it exposes said grooved face of said base and a second locking position wherein it overlies said face and the peripheral edges of the panel to clamp the panel therebetween;

said flap portion having on its groove-facing surface a longitudinal bead so dimensioned and contoured to compliment and snugly but removably lock in said groove to firmly clamp said base and flap portions in their locked position;

the improvement comprising said hinge portion being a thin walled flexible web of sufficient length between the points where it joins said flap and base portions to permit the flap portion to move laterally relative to the base portion a substantial distance when caused so to move, independent of its pivotal movement about said hinge portion;

with the parts being so constructed that movement of said flap portion toward its locking position causes said bead to make initial contact with said base inner leg, the interference therebetween causing said flap portion to be cammed by the base inner leg and shifted laterally outwardly toward said base outer leg, to the extent permitted by the yieldable hinge portion, until said bead engages said base outer leg;

continued pivoting of said flap portion causing said bead to cam said base outer leg outwardly slightly to temporarily widen the groove for reception of said bead;

and continued pivoting of said flap portion causing said bead to snap into its locked position within said groove.