Abstract:
A flexible face material sign framing system allows the interior portion of the sign casing to be accessed without removing the face material from the framing. The system includes a device for grasping the flexible face material and exerting tension to its edges in order to tighten the front of the sign appropriately. The system and device are weatherproof and therefore prolong the life of the face material.

Description:
FIELD OF THE INVENTION 
     The present invention relates in general to a flexible face sign framing system and device, and more particularly to a framing system and device which allows a sign to be opened without removing the liable material. 
     BACKGROUND OF THE INVENTION 
     Flexible face material is often used to cover the front surface of an illuminated sign. The signs mostly comprise a generally rectangular casing containing the source of illumination, and on which the front face is covered by flexible face material (flexface). The illumination means can falter or wear out before the casing and front face of the sign. Therefore, easy access to the lighting system is necessary once the sign has been installed. Because the fronts of such illuminated signs are covered by the flexface material, the usual practice for maintenance and inspection of an illumination system involves the temporary removal of the flexible face. However, because the front face is the element of the sign to which attention is meant to be drawn, the flexface material needs to be aligned perfectly without any wrinkles or folds. The proper reinstallation of the flexface after repair or maintenance can be difficult when done on site. The cyclical release of tension and reinstallation of the flexface has a detrimental fatigue effect en the face material. By constantly releasing the tension and then reapplying it, the flexface can stretch and lose its tautness, thereby affecting the aesthetics of the front of the sign Therefore, it is preferable if the flexface material is not removed from its position in the casing when access to the interior of the sign is required to repair, maintain or simply inspect the illumination system. 
     In addition, the methods and devices used to hold the flexface material into the sign casing need to be easy to install, remove and maintain. The signs have to be resistant to the difficult climactic conditions to which it they are subjected to once installed. Rainfall and snowfall, combined with freezing temperatures and high winds require the holding devices to withstand high pressures and forces in order to prevent the destruction of the sign. Water infiltration can cause severe damage to the structural elements of the casing of the sign, particularly if the sign is then subjected to sub-zero temperatures. Therefore, the methods and devices used to hold the sign within the casing must not only be resistant to high stress but must be watertight as well. 
     It is also important to maintain the integrity of the flexface material. The face of a sign can be reused and any breach of the material could substantially reduce its usefull life. Therefore, the methods and devices used must hold or grasp the flexface without ripping, cutting or piercing it. 
     While maintaining the resistance to the elements and the structural integrity of the flexface, the aesthetic nature of the face material must remain a key feature in illuminated signs, in particular because an even illumination of the entire flexface from edge to edge is required of an illuminated sign. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a flexible face material sign framing system with illumination means therein, wherein said framing system allows easy access to the illumination mans without removing the flexible face material from the casing. 
     In accordance with an aspect of the present invention there is provided 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described with reference to the accompanying drawings which show a preferred embodiment thereof and wherein: 
     FIG. 1 illustrates in a partial perspective view, a flexible face sign framing system with a front casing pivoting about a rear casings; 
     FIG. 2 illustrates in a cross-sectional view, the sign framing system of FIG. 1 along line  2 — 2 ; 
     FIG. 3 illustrates in a partial cross-sectional view, the sign framing system of FIG. 1 along line  2 — 2 ; 
     FIG. 4 illustrates in a side elevation view, a tension clip used in the framing system. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIG. 1, there is illustrated a flexible face sign framing system  10  comprising a front sign cam  12  pivotally connected to a rear sign casing  14 , said front and rear sign casings forming a generally rectangular sign casing  16  for containing illumination means  18  (shown in FIG.  2 ). Front sign casing  12  has a front face  20  covered by a flexible face material  22  which displays the visual information of the sign, either illuminated at night or without illumination during the day. 
     Referring to FIGS. 1 and 2, rear sign casing  14  has an interior portion for containing illumination means  18 . The rear casing is formed by a top panel  24 , a bottom panel  26 , a first and second end panels  28 ,  30  and a back panel  32 , all connecting perpendicularly at the edges of the rear sign casing  14 . Top, bottom and end panels  24 ,  26 ,  28  and  30  are formed in a preferred embodiment, by an aluminum extrusion  34 . Extension  34  has a web portion  36 , a rear flange  38  extending at right angle from the rear edge  40  of web portion  36 , and a front flange  42  extending at right angle from the front edge  44  of web portion  36 . The front edge  44  has an open channel  46  for receiving part of the front sign casing  12 . Flat back panel  32  is secured to the rear flange  38  of the extrusion  34  of each of the panels  24 ,  26 ,  28  and  30  of the rear sign casing  14 . Thus, panels  24 ,  26 ,  28  and  30  and back panel  32  form the exterior of the rear sign casing  14 . A plurality of U-shaped bracing members  50  are secured to the interior of the elongated extrusion  34  of top panel  24  and bottom panel  26 , and the back panel  32 . U-shaped bracing members  50  are positioned in a spaced relationship longitudinally along the width of the rear sign casing  14  to improve the rigidity of the rear sign casing. Illumination means  18  are mounted on the back panel  32  and the bracing members  50 , and extend longitudinally along the width of the rear sign casing  14 . Reflectors  51  are diagonally mounted at the corners of the rear sign casing  14  to reflect light from the illumination means onto the front face  20 . 
     Referring to FIG. 3, front sign casing  12  is positioned immediately in front of the rear sign casing  14  and is for supporting the flexible face material  22  onto the front face  20  of the sign casing. Front casing  12  includes a front edge member  52  which forms top member  54 , bottom member  56 , and first and second end members  58 ,  60  of the front casing. Each of the members  54 ,  56 ,  58  and  60  of the front sign casing  12  are aligned with the corresponding panels  24 ,  26 ,  28  and  30  of the rear sign casing  14 . Front edge member  52  has a main recess  62  into which the flexible face material  22  is received. In a preferred embodiment, front edge member  52  is an aluminum extrusion. Front edge member  52  includes a rearwardly extending member  64  which is received in the shallow channel  46  of rear sign casing  14 , and a primary member  66  extending at right angles from rearwardly extending member  64  and towards the interior portion of the front casing  12 . Front edge member  52  also includes first and second slot arms  68  and  70  extending from primary member  66  substantially parallel to the rearwardly extending member  64 , said first slot arm having an indentation  72  thereon. First and second slot arms  68  and  70  form a first slot  74  extending longitudinally along the length of the front edge member  52 , said first slot  74  for receiving a connection tongue  76 . Below first slot  74  and extending from primary member  66 , there is a pair of parallel webs  78  extending longitudinally along the length of front edge member  52  and angled towards the front face  20  of the front casing  12 , into recess  62 . Webs  78  have ridges  79  extending longitudinally along the length of the front edge member  52 . A second slot  80 , extending longitudinally along the length of front edge member  52 , is located under the parallel webs. An angulated arm  82  extending from the members  81  forming second slot  80  is substantially parallel to the flanges  78 , said angulated arm  82  having an elbow  84  at its midpoint, and having a lip  86  at its end  88 . Lip  86  of front edge member  52  on each of the members  54 ,  56 ,  58  and  60  forms a surrounding edge  90  of the front face  20  of the front sign casing  12 , which front face  20  is covered by flexible face material  22 . 
     Front sign casing  12  also includes a series of regularly spaced C-shaped bracing members  92  each secured between the top and bottom front casing members  54 ,  56 . Each C-shaped brace  92  is made up of a spanning member  94  and a pair of arms  96  which are angled and extending away from spanning member  94  and towards the second slot  80  of the front edge member  52 . Ends  97  of arms  96  are shaped to fit in second slot  80  and are secured therein with screw fasteners. Because the bracing members  92  are positioned between the illumination means  18  and the flexible face material  22 , the closer they are positioned to the illumination means, the less shadow will appear on the front face  20  of the sign. Members  92  are thus C-shaped with the spanning member  94  being adjacent illumination means  18 . The bracing members  92  give lateral support to the front sign casing  12  allowing it to be pivoted about the rear sign casing  14 . 
     Referring to FIG. 4, a pluralty of tension clips  98  are removably secured within the main recess  62  and are for holding onto an edge  100  of the flexible face material  22 . Clips  98  comprise an L-shaped member  102  having a screw hole  104  through it. From the inside corner  103  of the L-shaped member  102  extends a clamping leg  106  having a heel  108  thereon. When the edge of the flexible material is inserted between the member  102  and the clamping leg  106 , the leg is pivoted about a hinge  110  which is merely a narrowed neck  112 . The heel  108  is snap-fit into a lip  114  and thereby clamps onto the flexible material. 
     Each tension clip  98  is attached to the front edge member  52  with a screw fastener  116  which goes through screw hole  104 , between parallel webs  78 . The distance between the webs  78  is slighty less than the diameter of the screw fastener  116  and the pitch of ridges  79  allows the threads in the screw to grip into the ridges, thereby solidly securing itself between the webs. The screws are preferably made of steel and do eventually shear portions of the aluminum ridges of the webs to solidly attach to the extrusion. However, they may be repositioned along the extrusion as necessary. Tension clip  98  fits into main recess  62 , and the clamping leg and lip assembly fits into secondary recess  118 , when the fastener  116  is tightened. Because the tension clips merely grasp the flexible face, it does not damage the material and therefore extends its useful life. 
     The front sign casing also comprises a cap  120  which fits to cover the main recess  62  of the front edge member. The cap  120  extends between the first slot arm  68 , and lip  86  of angulated arm  82 . A first weather gasket  122  is positioned between indentation  72  on first slot arm  68  and cap  120  and acts to prevent water infiltration form the top of the casing into the front edge member. Flexible face material  22  passes between cap  120  and lip  86  of angulated arm  82 , and then into tension clip  98 . The face material is held in tension between the tension clip and the angulated arm  82 . Because off the angle in the arm, when the screw fastener  116  is turned, the clip is driven partially towards the angulated arm which increases the tension in the flexible face. 
     A second weather gasket  124  is positioned between the front flange  42  of the extrusion  34  of the rear sign casing and the primary member  66  of the front edge member. The second gasket is for preventing water infiltration from between the front and back sign casings and into the interior portion of the sign. 
     Front sign casing  12  is pivotally connected to rear sign casing  14  via a hinge  126  mounted to the extrusion  34  of the top member  24 , the hinge allowing front sign casing to pivot about the hinge and expose the interior portion of the rear sign casing. 
     The flexible face material  22  covers the front face  20  of the front sign casing  12  and extends between tension clips  98  in the front edge member of the top member  54  and those in the bottom member  56 , and between tension clips  98  in the front edge member of the first end member  58  to those in the second end member  60 . Screw fasteners  128  are for securing the bottom  56  front edge member  52  to the bottom panel  26  of the extrusion  34 . 
     To install the system, the rear casing  14  is fitted with illumination means  18 . Flexible face material  22  is fitted around its edge  100  with a plurality of tension clips  98  which are inserted within main recess  62  of the front edge member  52 . The clips are secured to the front member with the screw fasteners  116 . Once the flexible face material  22  is completely inserted within the casing, caps  120  are mounted over the main recess in members  54 ,  56 ,  58  and  58 . 
     Once the sign casing is installed in its desired site, its interior can be accessed by releasing screw fasteners  128  from the bottom member, and the front sign casing  12  can be pivoted about the hinge  126  to allow the illumination means  18  to be inspected, repaired or changed. If the flexible face material loses some of its tautness after a period of time, the tension in the face can be increased simply by tightening the screw fasteners  116 , whereby the tension clips would be inserted deeper into main recess  62 , and slightly towards angulated arm  82 , and pull the face material tighter. 
     In addition, the shape of angulated arm  82  allows the light rays from the illumination means to reach the entire outside surface of the front face  20 . The sign casings can be connected to one another in order to make them longer by insert the connection tongue  76  into first slot  74 . The connection feature also allows for easier transportation of the longer sign casings. Because of the two part casing, the rear casing which contains the illumination means and which must be maintained in one piece, can be transported separately from the front casing  12 . The front casing sections can be folded onto one another, even with the face material installed, with the flexible face material acting as a hinge between the lengths of front casing  12 . With one piece sign casing, the flexible face must be installed on site since transportation of long specimens with the flexible material installed is liable to cause damage to the front face and therefore render the sign useless. This site installation is very difficult and even dangerous. With the two part casing, the flexible material can be installed at the plant and then transported to the site with the flexible face safety protected between the respective lengths of the front casing. On site, all that has to be done is insert the connection tongues inside the first slots and install the front casing onto the rear casing and install the sign onto the site. 
     The above-described embodiments of the present invention are meant to be illustrative of preferred embodiments and are not intended to limit the scope of the present invention. Various modifications, which would be readily apparent to one skilled in the art, are intended to be within the scope of the present invention. The only limitations to the scope of the present invention are set forth in the following claims appended hereto.