United States Patent 1191 MacDonald 1451 Apr. 24, 1973 I MOLDED SCREEN FRAME [56] References Cited IDVCDtOi'I R0119" D. MacDonald, Adrian, UNITED STATES PATENTS Mich. 1 2,623,250 12 1952 Chilton ..52/403 x ASSIgHeB-I Cardinal of Adrian. Adrlan. 3,360,893 1/1968 Wattelez ..52/476 x Mich. 3,379,237 4/1968 Warthington ..l60/37l [22] Filed: 197] Primary ExuminerKenneth Downey I [2] 1 App]. No.: 106,009 Att0rney-Cullen, Settle, Sloman & Cantor Related US; Application Data 57 ABSTRACT [63] Continuation-impart of Ser. No. 77,624, Oct. 2, A one piece plastic molded window Screen frame 1970 abandmed I comprises a bead-carrying locking flap which is con- I nccted by an integral hinge to a grooved base portion. [52] US. Cl. "160/371, loo/380, 22/476, The edge of the Screen panel is firmly but removably Y I 60/395 retained between the interlocking bead and groove. [5 i 1 Int. Cl. The frame also has integral tabs which g g grooves [58] Field ofSearch ..160/37l, 380;
in the window opening to retain the frame therein.
1 Claim, 6 Drawing Figures Patented April 24, 1973 3,729,045
INVENTOR.
ROBERT D. MAC DONALD.
CULLEN, SETTLE, SLOMAN 8 CANTOR.
ATT'YS.
MOLDED SCREEN FRAME CROSS-REFERENCE TO RELATED APPLICATION This application is a continuationdn-part of my earlier application Ser. No. 77,624, filed about Oct. 2, I970 now abandoned.
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 crosshatching, 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 ofarrows S5 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 show-- ing 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 plasticrectangular frame 10, generally comprising abase portion 12 and alocking portion 14 connected tobase 12 by a thin-walled continuousintegral 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 thehinge 16. In a preferred embodiment, the thickness of binge I6 is approximately OBIS-0.020 inches, and the total width ofbase 12 is about three-fourths an inch.
FIGS. 2 and 3 show frame in its as-molded and open condition, FIG. 3 being a typical cross-section through any side of the frame.Base 12 has anupper face 18 which is provided with a deep andwide groove 20.Locking flap 14 is provided with acontinuous bead 22 which is dimensioned and shaped tocompliment groove 20, so that when the edge of screen panel 24 (see FIG. 5) is stuffed intogroove 20, the screen panel will be firmly locked between the interlockingbead 22 and the groove 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. Aslocking flap 14 is pivoted towards its closed position,corner 26 ofbead 22 makes initial contact withedge 28 ofgroove 20 inframe base 12. This position is shown in solid lines in FIG. 4.
Because of the readily apparent interference betweencorner 26 andedge 28, it becomes necessary for some portion of the assembly to yield to permit further closing oflocking flap l4.
Initially, continued downward pressure on lockingflap 14 causes the rounded surface ofcorner 26 to be cammed to the left byedge 28. To accomplish this, hinge 16 yields toward the left, until shoulder 30 ofbead 22 contacts the outer or left side wall ofgroove 32. Continued downward pressure on lockingflap 14 causes continued leftward movement of bead shoulder 30 againstgroove sidewall 32, causing the upper outer portion ofbase 12 to yield toward the left. This condition is shown in phantom lines in FIG. 4. Only after the combined yielding of hinge l6 andsidewall 32 can bead 22 complete its entry intogroove 20. Oncecorner 26 is fullypast 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 yieldingouter sidewall 32 ofgroove 20 functions to reduce the amount of load and strain placed onhinge 16 during opening or closing of the frame, thus reducing the danger of premature failure of the hinge.
One method of retainingframe 10 in a window opening is by the provision of a series of molded integralre tention tabs 34 shown in FIGS. 1 and 5. Such tabs are received bygrooves 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 alocking tab 42 which engages agroove 44 in window sill 46. Retention member 40 is molded in such a way that it has a natural position of approximately 45 to clockwise from the position shown in FIG. 6, so that it has a continuous downward or clockwise bias to retaintab 42 ingroove 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 inface 18 of sufficient depth to receive the framed panel. The retained panel would not extend as far outwardly asgroove 20, but would be simply retained by the interlock betweenface 18 and the opposed face offlap 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.
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 Ushaped 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 portion; hinge portions;
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.