Abstract:
A retainer strip assembly for securing screening and screen covering and the like to a framing member comprises a base strip, cover strip and cap strip fastened to the framing member, the cap strip covering the base strip and holding in place the screening and screen covering, and the cover strip contained within the base strip for avoiding the tearing or fraying of screen covers when the cap strip is placed on or removed from the base strip while installing or removing screen covers.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to retainer strips for screens and screen covers, and, more particularly, to low-profile, universal retainer strips for removably fastening screen covers to framed screens and the like, such as are used for porches. 
     Screened porches remain a popular addition to constructions, as they enhance the enjoyment of the out-of-doors regardless of ambient conditions. The screening blocks the entry of insects and admits air to the area of the porch so enclosed. Although meshed screens are ideal to block the entry of undesired objects, while still maintaining a comfortable temperature for the occupants, these screens must frequently be replaced because of damage or degradation. Additionally, the screening can become dirty so as to require cleaning, which cannot be done effectively with the screens in place and it is impractical to clean the screens by removing them completely. 
     Typically, porches are screened by erecting a simple wooden framing to enclose the porch in a series of panels and to which framing the screening material is nailed or tacked. The nails or tacks are covered with furring strips to give the structure a finished appearance. Removal of the screening, therefore, involves prying off the furring strips and pulling the nails or tacks from the framing with the resulting damage to the framing. Furthermore, the screening may run over several panels so that a large area of screening may have to be replaced to effect a repair needed in only one panel. 
     In some areas of the country, such as along the sea coast, where screening is especially susceptible to damage, and where relatively frequent replacement of screening is necessary, elaborate framing with removable screened elements is available. This framing is usually made of aluminum and is relatively expensive to install. It also lacks the flexibility of wood framing and, to some, the aesthetic appeal of painted or stained wood. 
     One device for attaching screens to framing is described in U.S. Pat. No. 4,899,797, issued to the present inventor, which is incorporated herein by reference. In this prior art device, a low-profile, universal retaining strip is provided for removably fastening screens and the like to framing. 
     During colder months, screen covers are temporarily used over screening to keep porches warmer by both blocking cold air from flowing into the porch and helping to keep warmer air within the porch. This approach is sometimes referred to as “winterizing,” which results in “winterized” porches. These screen covers are typically thin clear plastic, such as made from polyethylene or vinyl. The more fitted these covers are to the mesh screens, the more effective they are at maintaining a comfortable porch climate. Although a snug fit between the screens and the screen covers can be achieved through the use retaining strips, such as the Green device, these strips oftentimes tear or fray the screen covers during either the removal or installation of the covers. Furthermore, screen covers can neither be repaired nor reused once they are torn. 
     Accordingly, there remains a need for a retaining strip that can removably fasten both screens and screen covers without also damaging the screen covers. 
     SUMMARY OF THE INVENTION 
     The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key or critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concepts of the invention in a simplified form as a prelude to the more detailed description that is presented later. 
     According to its major aspects and briefly stated, the present invention includes a screen cover retainer strip assembly having a cap strip removably fastened onto a base strip that is fastened to a framing member. The base strip includes at least one narrow groove for receiving and holding temporarily a spline with a screen, and a channel for receiving and holding temporarily a cover strip and a screen cover. The cap strip covers the spline and base strip and assists in securing the spline within the narrow groove. Additionally, the cap strip assists in securing both the cover strip and the screen cover within the channel. 
     The present invention has a low profile, being only slightly thicker than a spline and is preferably an extruded all-weather, resilient plastic in white or other desirable color for low maintenance. Alternatively, the base strip may be made of aluminum or other metal and only the cap strip and cover strip made of plastic. The cap strip serves primarily to hold the cover strip, screen cover and spline in place, and cover the base strip including the heads of nails or screws used to fasten the base strip to the framing member. So embodied, the strip assembly does not detract from the appearance of the structure to which the screening is to be fastened. Cap strip removal is easily accomplished by inserting a screw driver or other narrow lever at any point along the interface between base strip and cap strip and prying the two apart. The cap once loosened will peel off to allow access to the screen and screen cover for replacement. 
     A feature of the present invention includes the use of a cover strip to within the channel of a base strip. So as to maintain the enjoyment of screened porches, screen covers are typically a thin layer of transparent plastic. Accordingly, screen covers are easily damaged, and oftentimes cut, when contacted by an edge. The cover strip of the present invention helps to prevent this type of screen cover from being cut, torn or frayed, especially by the interaction between the cap strip and the base strip, during either the application or replacement of the cover. 
     Another feature of the present invention includes the use of a cap strip dimensioned to removably retain a cover strip within the channel of a base strip. The cap strip is dimensioned to bear against the cover strip so as to hold the screen cover in place without tearing or fraying the screen cover during the application or replacement of the screen cover. 
     Other features and advantages of the present invention will be apparent to those skilled in the art from a careful reading of the Detailed Disclosure of the Preferred Embodiment presented below and accompanied by the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings, 
         FIG. 1  is an exploded perspective view of a prior art retainer strip assembly; 
         FIG. 2  is an end view of a prior art retainer strip assembly; 
         FIG. 3  is an exploded perspective view of a retainer strip assembly according to the present invention; 
         FIG. 4  is an end view of a retainer strip assembly according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention is screen cover retainer strip assembly for use in attaching both a screen and a screen cover to framing, such as in porches. The present retainer strip assembly is an improvement over prior art retainer strips in that it removably fastens screen covers to framing without also damaging the screen covers. 
     Referring now to the figures,  FIGS. 1-2  represent a prior art retainer strip assembly shown in a perspective view and generally indicated by reference number  10 . The retainer strip assembly  10  shown is secured to a framing member  12 . Assembly  10  comprises a base strip  14  and a cap strip  16  both running parallel to the long dimension of framing member  12 . 
     Retainer strip assembly  10  may be used to secure any type of flexible sheeting such as cloth, canvas, plastic or mesh screening to framing member  12 .  FIG. 1  shows a mesh screen  18  secured to frame member  12 . 
     As shown in  FIG. 2 , showing an end view of retainer strip assembly of  FIG. 1 , screen  18  is fastened to either side of retainer strip assembly  10  where a marginal portion  20  of screen  18  surrounds a resilient, cylindrical spline  22  having a series of teeth  24  about its exterior surface (as best seen in  FIG. 2 ). Spline  22  is received by a narrow groove  26 . When retainer strip assembly  10  is fastened to an intermediate framing member having screening on either side, such as shown in  FIG. 1 , a second groove  28  receives a second spline. Grooves  26  and  28  are sufficiently narrow so that a spline received therein is held temporarily; that is, grooves  26  and  28  can hold spline  22  with screen  18  and exerting a small amount of tension on spline  22  without spline  22  slipping out of groove  28 . Alternatively, when retainer strip assembly is fastened to an end framing member having screening on one side, only one groove is required. 
     Between groove  26  and  28  is a channel  30  defined by a left wall  32 , a right wall  34  and a floor  36 . Screws or nails can be driven through the floor  36  of channel  30  to hold base strip  14  to frame member  12 . Preferably, holes  58  (shown in  FIG. 1 ) may be drilled into floor  36  at the time of fabrication to assist in the attachment of base  14  to frame member  12 . Alternatively, base strip  14  can be glued to frame member  12 . 
     Left wall  32  and right wall  36  have inwardly protruding lips  40  and  42 , respectively, and outwardly protruding bulges  60  and  62 . Cap strip  16  both serves to cover base strip  14  and to hold spline  22  in place. Cap strip  16  has a top  44 , a left side  46  and a right side  48  substantially covering base strip  14 . Under top  44  are a left catch  50  and a right catch  52  positioned between left and right walls,  32 ,  34 , respectively of base strip  14 . So positioned, catches  50 ,  52  hook onto the protruding lips  40 ,  42  of left and right walls  32 ,  34 , respectively. 
     In addition to holding cap strip  16  to base strip  14 , catches  50 ,  52  bear outwardly against left and right walls  32 ,  34 , respectively, which thereby pinch splines in the grooves and assist in holding screen  18  against substantial tension. 
     The sides of cap strip  16  finish the side appearance of retainer strip assembly  10  and also fold screen  18  down around the outside of groove  28 , adding further resistance against the dislodging of spline  22  and screen  18 . A left outer wall  54  and right outer wall  56  of base strip  14  are slightly recessed to create slits between base strip  14  and the sides of cap strip  16  for insertion of a tool such as a screw driver to pry cap strip  16  from base strip  14  without the screw driver bearing directly against frame member  12 . 
     Cap strip  16  and base strip  14  can both be made of a resilient plastic, each extruded in any appropriate color, or made of metal. When in place, the retainer strip assembly has a low, unobtrusive profile. 
     If desired, retainer strip assembly  10  can be made with only one groove for use as a retainer strip assembly attached to end framing members. 
       FIGS. 3-4  illustrate perspective and end views of a present retainer strip assembly  80  which represents an improvement over retainer strip assembly  10 . Like retainer strip assembly  10 , assembly  80  is secured to a framing member  82 . Assembly  80  comprises a base strip  84 , a cover strip  90  and a cap strip  86 , each running parallel to the long dimension of framing member  82 . 
     Retainer strip assembly  80  may be used to secure any type of flexible sheeting such as cloth, canvas, plastic or mesh screening, as well as screen covering, to framing member  82 .  FIG. 4  shows a mesh screen  88  and a sheer screen cover  89  secured to frame member  82 . In particular, the screen cover  89  can be made of a thin, clear plastic, such as polyethylene or vinyl. The purpose of the screen cover  89  is to winterize a porch so that it can be enjoyed by users during colder months or in colder climates. 
     As further illustrated in  FIG. 4 , showing an end view of retainer strip assembly  80  of  FIG. 3 , screen  88  is fastened to either side of retainer strip assembly  80  where a marginal portion of screen  88  surrounds a major portion of a first resilient, cylindrical spline  92  having a series of teeth  94  about its exterior surface. Spline  92  is received by a narrow groove  96 . A second groove  98  can also receive a second spline  93  when retainer strip assembly  80  is fastened to an intermediate framing member having screening on either side, such as shown in  FIGS. 3-4 . Grooves  96  and  98  are sufficiently narrow so that a spline received therein is held temporarily; that is, grooves  96  and  98  can hold splines  92 ,  93  with screen  88  and exerting a small amount of tension on splines  92 ,  93  without splines  92 ,  93  slipping out of grooves  96 ,  98 . Alternatively, when retainer strip assembly  80  is fastened to an end framing member having screening on only one side, only one groove is required. 
     Between groove  96  and  98  is a channel  100  defined by a left wall  102  and a right wall  104  separated by a floor  106 . Left wall  102  and right wall  104  of channel  100  have inwardly protruding lips  110  and  112 , respectively. As shown, channel  100  is dimensioned to receive screen cover  89  and cover strip  90 . Cover strip  90  is surrounded by screen cover  89  when the assembly is in place. Preferably, cover strip  90  has a flat, rectangular shape with a bottom surface  91  next to the floor  106 , and side walls  95 ,  97  next to the left wall  102  and right wall  104  of channel  100 , respectively. Additionally, left wall  102  and right wall  104  preferably include inwardly protruding flanges  111  and  113 , respectively, that extend longitudinally and that are dimensioned to releasably retain cover strip  90  and screen cover  89  within the channel  100 , such as by a loose snap-fit. The outer surface, including top surface  99 , of cover strip  90  can either be smooth or ridged, such as shown in  FIGS. 3-4 . 
     Similar to previous retainer assembly  10 , screws or nails can be driven through the floor  106  of channel  100  to hold base strip  84  to frame member  82 . Accordingly, holes (not shown) may be drilled into floor  106  at the time of fabrication to assist in the attachment of base  84  to frame member  82 . Alternatively, base strip  84  can be glued to frame member  82 . 
     Cap strip  86  serves to cover base strip  84  and to hold both screen cover  89  and splines  92 ,  93  in place. Cap strip  86  has a top  114 , a left side  116  and a right side  118  substantially covering base strip  84 . Under top  114  are a left catch  120  and a right catch  122  positioned between left and right walls,  102 ,  104 , respectively of base strip  84 . Preferably, catches  120 ,  122  include a left and right end flange  130 ,  131 , respectively. So positioned, one side of left and right end flanges  130 ,  131  hook onto the protruding lips  110 ,  112  of left and right walls  102 ,  104 , respectively, while the other side of left and right end flanges  130 ,  131 , abut or bear on cover strip  90 , respectively. Additionally, inwardly protruding flanges  111  and  113  can also assist in holding catches  120 ,  122  in place. 
     When screen cover  89  is applied, screen cover  89  is preferably wrapped over grooves,  96 ,  98 , around catches  120 ,  122  and beneath cover strip  90 . A feature of the present invention includes the use of cap strip  86  in combination with cover strip  90  within channel  100  of base strip  84 . Catches  120 ,  122  of cap strip  86  are dimensioned to bear outwardly against left and right walls  102 ,  104 , respectively, and thus assist in holding screen cover  89  against substantial tension, as shown in  FIG. 4 . Furthermore, because catches  120 ,  122  also abut cover strip  90 , potential tearing and fraying of the screen cover  89  by catches  120 ,  122  is avoided. Inwardly protruding flanges  111  and  113  further assist in both maintaining the cover strip  90  and screen cover  89  in place, as well as positioning the catches  120 ,  122  for holding the cover strip  90  and screen cover  89  within the channel  100 . 
     In addition to holding cap strip  86  to base strip  84 , and holding cover strip  90  and screen cover  89  in place, catches  120 ,  122  also assist in pinching splines  92 ,  93  in grooves  96 ,  98  and thus in holding screen  88  against substantial tension, as seen in  FIG. 4 . 
     The sides of cap strip  86  finish the side appearance of retainer strip assembly  80  and also fold both screen  88  and screen cover  89  down around the outside of grooves  96 ,  98 , adding further resistance against the dislodging of splines  92 ,  93 , screen  88 , and screen cover  89 . A left outer wall  134  and right outer wall  136  of base strip  84  can be slightly recessed to create slits between base strip  84  and the sides of cap strip  86  for insertion of a tool such as a screw driver to pry cap strip  86  from base strip  84  without the screw driver bearing directly against frame member  82 . 
     Cap strip  86 , base strip  84 , and cover strip  90  can be made of a resilient plastic, each extruded in any appropriate color, or made of metal. When in place, the retainer strip assembly has a low, unobtrusive profile. 
     The foregoing description of preferred embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teachings. The embodiments were chose and described in order to best explain the principles of the invention and its practical application to thereby enable one skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto.