You are an expert at summarizing long articles. Proceed to summarize the following text:

You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This invention relates to extruded moldings and, more particularly, to a set of interlocking extrusions for use in attaching panels of a shower enclosure. 
         [0003]    2. Background 
         [0004]    Certain shower enclosures, such as are used in recreational vehicles and the like, are constructed of prefabricated glass panels and at least one door panel that includes a door and doorframe. During the installation of such a shower enclosure, it is required to join together multiple panels of glass and their respective frames that protect the edges of the glass. One example of such a shower enclosure is designed for a corner installation with three panels, two adjoining the walls and perpendicular thereto, and a third, often comprising the door and doorframe, diagonally between the other two at a 135° angle with respect to each. This is often referred to as a “Neo-Angle” shower design. 
         [0005]    There are numerous connection systems for attaching adjoining panels of framed glass of shower enclosures. Most existing shower enclosures use some form of an interlocking design feature to engage multiple glass panels/doorframes within the installation process, however there remains additional room for improvement. 
         [0006]    During the installation process it is required to quickly and safely bring together and stabilize multiple glass panels/doorframes prior to permanent engagement. During this initial assembly and adjustment process, there is usually one installer who must maneuver numerous panels/doorframes at the same time prior to fastening them together in a “permanent” engagement. Existing shower enclosures lack a feature that is effective in securing the panels prior to the permanent fastening stage. Disengagement of adjoining panels during installation is problematic as a result of delays in the installation process as well as the risk for damaged property and personal injury to the installer. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention provides a set of extruded interlocking moldings that provide a unique and superior method of joining together panels of framed glass and/or framed glass doors. A first molding has a channel along an edge of one face and a groove in the opposite face. A second molding has a tongue extending along an edge of one face and a flange along an edge of the opposite face. The channel of the first molding is configured to receive and hold the tongue of the second molding to secure the moldings together as the panels are aligned. The flange of the first molding snaps into the groove of the second molding when the moldings are rotated to a predetermined angle with respect to each other. 
         [0008]    Some of the benefits of the present invention are:
       An easier, safer and quicker installation. A “leading-outside-engagement feature” of the extrusions engages in a manner so that when the extrusions are rotated toward the permanent engagement position, the connection does not allow separation in the installation process.   A secure connection between the door and fixed panels. Following the leading-outside-engagement feature connection, an “inside-engagement feature” then engages in a “snapping” function that locks and holds the panels permanently in the proper alignment. Upon permanent engagement, the relationship of the leading-outside-engagement feature and the inside-engagement feature reduces lateral or twisting action. The resulting strength of the fully assembled joint (i.e. “permanent” engagement) precludes the need of using fasteners to secure the panels together.   Saving in material cost. The strength and stability of the fully assembled joint inherent in the moldings of the present invention reduces the amount of frame material required. Conventional frame moldings are thicker to accommodate fasteners, typically 3-5 screws per post, and access thereto. Since no fasteners are needed to assemble the moldings of the present invention, they can be substantially thinner. As a result, it is feasible to reduce the width of the frame material by up to 50%.       
 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is a perspective view of a prior art shower enclosure. 
           [0013]      FIG. 2  is a detailed cross-sectional view of a pair of prior art moldings for forming a corner of a shower enclosure. 
           [0014]      FIG. 3  is a detailed cross-sectional view of the moldings shown in  FIG. 2  after being permanently attached. 
           [0015]      FIG. 4  is a detailed cross-sectional view of a pair of moldings in accordance with an embodiment of the present invention. 
           [0016]      FIG. 5  is a detailed cross-sectional view of the moldings shown in  FIG. 4  after being permanently attached. 
           [0017]      FIG. 6  is a magnified view of the inside engagement feature of the present invention. 
           [0018]      FIG. 7  illustrates the reduction in material made possible with the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    In the following description, for purposes of explanation and not limitation, specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known methods and devices are omitted so as to not obscure the description of the present invention with unnecessary detail. 
         [0020]      FIG. 1  is a perspective view of a typical Neo-Angle shower installation utilizing prior art extruded moldings. Enclosure  10  comprises a door and doorframe  12  and two fixed panels  14 , 16  on either side of the door. The fixed panels are attached to the walls and the doorframe is attached between the fixed panels along each side edge. 
         [0021]      FIG. 2  is a cross-sectional view of the prior art extruded moldings  18  and  24  that form the adjoining edges of panel  14  and door/doorframe panel  12 . During installation of a typical Neo-Angle shower joint design, the adjoining panels are initially brought together prior to the permanent fastening stage. To facilitate this initial alignment, panel edge molding  18  has a hook-shaped leading edge  20  that engages a rearward facing protrusion  26  on doorframe molding  24 . These features are referred to collectively as “leading-outside-engagement feature”  32 . This engagement feature, while helpful for initially aligning the panels, fails to positively engage the two moldings and therefore allows the panels to become easily disengaged, particularly when subjected to the tilting and twisting forces that are commonly applied during panel alignment. Notice, in particular, how the shape of the leading-outside-engagement feature  32  of extrusions  18  and  24  allows panel  14  to separate from doorframe  12  in any of the indicated directions during the initial assembly and adjustment process. 
         [0022]    Prior art moldings  18  and  24  also incorporate an “inside-engagement feature”  34  comprising flange  22  on panel edge molding  18  and groove  28  in doorframe molding  24 . After the leading-outside-engagement feature  32  has been engaged, panel  12  is rotated counter-clockwise to engage flange  22  in groove  28  as shown in  FIG. 3 . Note, however, that engagement of both the leading-outside-engagement feature  32  and the inside-engagement feature  34  is insufficient to lock panel  14  and doorframe  12  together into permanent engagement because they fail to hold the panel and doorframe under lateral or twisting forces. Thus, shower enclosures constructed with prior art moldings  18  and  24  require the use of a plurality of fasteners  30  (only one of which is seen in the figure) to “lock” the adjoining panels together. All of the existing connection systems require multiple fasteners, usually three to five screws per connection, to permanently join the frame edges of the door panel and stationary panel. Since these existing connection systems require the use of screws, larger frame sections, which require more raw material, are necessary to allow space both for the screws and for access to the screws during assembly. 
         [0023]    Many prior art shower enclosure joint designs use both outside and inside engagement features similar to those described above; however, such engagement features nevertheless allow separation of the adjoining panels. Even with the use of screws  30  to fasten moldings  18  and  24  together, the assembly is still prone to gaps along the joints  32  and  34  due to the flexibility of the aluminum moldings. Note, in particular, that the leading-outside-engagement feature  32  does not positively lock together and therefore allows the moldings to separate as indicated by the arrows in  FIG. 3 . The resulting gap is not only aesthetically displeasing, but the separation of the moldings also reduces the structural integrity of the shower enclosure. Typically, only 3-5 screws are used along the length of the moldings. The use of additional screws would reduce the severity of the gaps, but would increase the material and assembly costs. The present invention also uses outside and inside engagement features; however, the design of the engagement features differs from the prior art in form, fit and function to achieve a variety of benefits. 
         [0024]    Referring now to  FIG. 4 , a pair of extruded moldings in accordance with an embodiment of the present invention are shown in cross section. Doorframe molding  110  is attached to the edge of door/doorframe panel  101 . Molding  110  includes a channel  116  along the edge of front face  112  and a groove  118  in the rear face  114 . Panel edge molding  120  is attached to the edge of fixed panel  102 . Molding  120  includes tongue  126  extending along the edge of front face  122  and a flange  128  along the edge of rear face  124 . A leading-outside-engagement feature, designated generally as  105 , comprises channel  116  of doorframe molding  110  and tongue  126  of panel edge molding  120 . This is the first feature to be engaged during installation. 
         [0025]    The leading-outside-engagement feature  105  becomes engaged as tongue  126  is captured within channel  116 . This first occurs when the door/doorframe panel  101  is at an angle of approximately 165° with respect to the fixed panel  102 . Once feature  105  is initially engaged, the door/doorframe panel&#39;s angle of orientation can be rotated slightly counter-clockwise (as viewed in  FIG. 4 ) toward a permanent engagement position in which feature  105  is in contact along the entire vertical length. At this point, the two moldings are held securely together by the full-length capture of tongue  126  within channel  116 . Note how the shape of the leading-outside-engagement feature  105  of the extrusions engage in a manner so that once engaged, the connection does not allow separation in any direction. This greatly facilitates the initial assembly and adjustment process, when usually one installer must maneuver numerous panels and a doorframe at the same time prior to their “permanent” attachment. The stability of the multiple glass panels afforded by the present invention results in an easier, safer and quicker installation process. 
         [0026]    With reference also to  FIG. 5 , an inside-engagement feature, designated generally as  106 , comprises groove  118  of doorframe molding  110  and flange  128  of panel edge molding  120 . From the position shown in  FIG. 4 , the door/doorframe panel  101  may be further rotated in a counter-clockwise direction to its permanent engagement position where flange  128  “snaps” into groove  118  to lock and hold the panels permanently in the proper alignment, providing a secure connection between the door/doorframe panel  101  and the fixed panel  102  without the use of fasteners. In the example shown, the flange snaps into the groove when the panels are at an angle of about 135°. 
         [0027]    Referring also to  FIG. 6 , the moldings  110  and  120  are configured so that molding  120  is “sprung” slightly when fully engaged with molding  110 , thereby urging the rear face  124  against rear face  114  and urging flange  128  into groove  118 . This self-locking feature of the joint obviates the need for additional fasteners to secure the panels together. Upon permanent engagement, the relationship of the leading-outside-engagement feature  105  and the inside-engagement feature  106  locks the panels together under any type of lateral or twisting force and thereby greatly reduces vibration and squeaking. The finished joint also allows for an aesthetically desirable flush mating of both the inside and outside surfaces of the shower enclosure, which is a major advantage of the present invention over the prior art. 
         [0028]    As explained above, the strength and stability of the fully assembled joint inherent in the moldings of the present invention obviates the need for mechanical fasteners such as screws. This allows for substantially thinner moldings and reduces the amount of frame material required.  FIG. 7  presents a comparison of the moldings of the present invention to those of the prior art to illustrate the reduction in material that can be achieved with the present invention. 
         [0029]    The present invention has been described with reference to a particular example of a shower enclosure; however, the invention may be applied in any application requiring the connection of adjoining panels. For example, while the invention has been described in the context of panels joined at an angle of 135°, suitably modified moldings substantially similar to those described above may be provided for joining panels at any desired angle. Furthermore, the invention has been described with reference to a tongue and channel engagement feature on the front faces of the interlocking extrusions and a flange and groove engagement feature on the rear faces. However, these engagement features could be reversed, yet still provide similar functionality and benefits. 
         [0030]    It will be recognized that the above-described invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the disclosure. Thus, it is understood that the invention is not to be limited by the foregoing illustrative details, but rather is to be defined by the appended claims.

Summary:
A set of extruded interlocking moldings joins together panels of framed glass and/or framed glass doors. A first molding has a channel along an edge of one face and a groove in the opposite face. A second molding has a tongue extending along an edge of one face and a flange along an edge of the opposite face. The channel of the first molding is configured to receive and hold the tongue of the second molding to secure the moldings together as the panels are aligned. The flange of the first molding snaps into the groove of the second molding when the moldings are rotated to a predetermined angle with respect to each other.