Abstract:
A mounting for a sheet to the side of a truck or the like includes attachment members forming a rectangle frame. Certain of the attachment members include frame members including mutually parallel multiple engagement surfaces defined on ribs. An elongate retainer, which cooperates with the frame members, is RF welded to the sides of the sheet. The retainer includes an elongate flange with an interlocking surface selectively interlocking with any one of the engagement surfaces on the frame. Both the frame member and the elongate retainer include rails. A tool including pinch rollers squeeze the rails toward one another to tension and mount the sheet. The sheet mounting for a roll-up door further includes rollers extending above the top of the door which are spring mounted. The sheet extends from the lower front of the roll-up door up over the rollers and is attached to the back side of an upper elongate panel of the roll-up door.

Description:
BACKGROUND OF THE INVENTION 
     The field of the present invention is apparatus and methods for the mounting of sheet material. 
     Advertising and other information is often temporarily presented on large sheets which are placed on billboards, truck panels and the like. One form of such sheet material is tensioned vinyl sheet. Such sheet may be printed upon and surrounded by a more rigid plastic border which is RF welded to the sheet. The border typically includes a large bead, circular in cross section, which operates as a tenon in association with a C-shaped mortise associated with a mounting frame. 
     Mounting frames may take on a plurality of configurations. Of value is the ability to tension the sheet and to maintain it in a tensioned and wrinkle-free state. Mechanisms have been used which first lock the sheet in place and then apply tension through off-center bolts and the like. 
     A recent system includes a mounting for a sheet that has a bead about its periphery. The system includes frame members forming a rectangle with each frame member having mutually parallel multiple engagement surfaces defined on ribs. As one utility, the frame has been mounted on trucks for advertising. The system further includes elongate retainers having elongate flanges with interlocking surfaces that can selectively interlock with any one of the engagement surfaces on the frame members and retainer mortise elements to receive the tenon beads on the periphery of the sheet. The frame also has frame rails having rail surfaces that face away from corresponding retainer rail surfaces on the rails of the retainers. A tool including pinch rollers squeezes the corresponding rail surfaces toward one another to place the sheet material held by the retainer in tension while the interlocking surface is engaged with the appropriate engagement surface. This system is illustrated in U.S. Pat. No. 6,276,082, the disclosure of which is incorporated herein by reference. To insure that the retainers do not inadvertently separate from the frame during use, a bead of elastic material has been wedged behind the elongate flanges and against the next adjacent ribs. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to an elongate retainer for mounting a sheet to an elongate frame member where the frame member includes an engagement surface and a frame rail surface with both of the surfaces facing away from the sheet. The retainer includes an interlocking surface positionable in interlocking engagement with the engagement surface and a retainer rail surface facing away from the frame rail surface, the rail surfaces being oriented such that they might be pinched toward one another for setting the retainer in engagement with the frame member. 
     In a first separate aspect of the present invention, the elongate retainer further includes a plate extending from the interlocking surface with a portion of the plate having a thin, flexible wall which is attachable to the sheet. 
     In a second separate aspect, the first separate aspect may further contemplate an elongate retainer formed by coextrusion of two materials with one forming at least a portion of the plate being more flexible than the other. The same portion may have a fusible surface for RF welding to the sheet. 
     In a third separate aspect of the present invention, a mounting including an elongate attachment, an elongate frame member parallel to and displaced from the elongate attachment and the elongate retainer are contemplated with the retainer having a fusible surface for attachment to the sheet. Again, the elongate retainer may additionally be formed by a coextrusion of two materials with the first demonstrating dimensional stability and the second being more flexible. The second is preferably associated with the portion having the fusible surface for attachment to the sheet. The engagement frame may also include mutually parallel multiple engagement surfaces to accommodate with variations in the mounted sheets. A tool may additionally be employed for the pinching of the rails toward one another to engage the retainer with the frame. This mounting may further be in combination with the sheet and with any panel such as the panel of a truck. 
     In a fourth separate aspect of the present invention, a mounting process retains one edge of two opposed edges of the sheet at an elongate attachment. The other opposed edge is welded to the elongate retainer. The elongate retainer and the frame rail are then manipulated by pinching the frame rail surface and the retainer rail surface to then move the interlocking surface laterally into engagement with an engagement surface. 
     In a fifth separate aspect of the present invention, the elongate frame member and the elongate retainer are further held together by a lock which includes a channel positionable over the retainer rail once the elongate retainer and the elongate frame member are interlocked. The channel has a first leg which interlocks with the retainer rail surface and a second leg which is compressed between the elongate flange which is in interlocking engagement with the engagement surface and the next adjacent elongate rib. This compressed second leg may be laterally compressible which may in turn be accomplished through flexible flanges extending laterally and being angled away from the end of that leg. 
     In a sixth separate aspect of the present invention, a mounting system is contemplated for a roll-up door which has elongate panels hinged together about axes which are parallel to the panels. The mounting includes a roller mount which is spring biased to extend beyond the upper end of the door, a roller rotatably mounted in the roller mount, an elongate attachment and an elongate frame member. The elongate retainer cooperates with the elongate frame member to retain one edge of the sheet. One of the elongate attachment and the elongate frame member is affixed at the inside surface of one of the panels of the roll-up door while the other is affixed at the outside surface of a lower panel. On the top panel, the attachment is outwardly of the roller. As a roll-up door is lifted, the outer vertical surface extends. The placement of the roller provides for an accommodation of that extension by retaining the path length of the sheet between the attachment and the frame member constant. 
     In a seventh separate aspect of the present invention, any of the foregoing aspects are contemplated to be employed in combination to additional advantage. 
     Accordingly, it is an object of the present invention to provide an improved mounting system for sheet material. Other and further objects and advantages will appear hereinafter. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is the side view of a truck having a mounting and a vinyl sheet mounted thereto. 
     FIG. 2 is an end view of an elongate frame member assembled with an elongate retainer of a mounting, with a sheet. 
     FIG. 3 is an end view of the elongate retainer. 
     FIG. 4 is an end view of a lock. 
     FIG. 5 is an end view of pinch rollers for association with the rails for mounting 
     FIG. 6 is an end view of a mortise bracket with a tenon associated with a sheet held therein. 
     FIG. 7 is a side view of a roller on a roll-up door over which a mounted sheet is to be tensioned. 
     FIG. 8 is the side view of FIG. 6 with the roller retracted. 
     FIG. 9 is a cross-sectional view taken along the center line of the springs of FIG.  6 . 
     FIG. 10 is a perspective view of a roller assembly on a roll-up door. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Turing in detail to the drawings, FIG. 1 illustrates a truck as one possible substrate upon which a mount can be fastened. The mounting system is affixed to the side panel  10  of the truck  12 . A sheet  14  is mounted on the panel  10 . The sheet  14  is contemplated to be vinyl, which may be printed upon and tensioned when mounted. As employed with the apparatus of FIGS. 6 through 10, the sheet may be mounted toga roll-up door as well. The sheet  14  is finished with a peripheral boundary defined by an elongate retainer as can best be seen in FIG.  2 . 
     In FIG. 1, two sets of members are illustrated to define a rectangular mounting. Both sets include an elongate attachment  20 . These attachments  20  may be identical elongate frame members  22  on each side of the sheet  14  or may include a simple clamp or mortise on one side with the elongate frame member  22  and associated hardware disclosed below on the other. The first set is shown to be horizontally disposed with the attachments  20  being mutually parallel and mutually displaced from one another. The second set is vertically disposed and also mutually parallel and displaced from one another. For convenience, the members  20  may all be identical extrusions of elongate frame members  22  but for orientation and length. The frame members  22  are easily mounted to the side panel  10  of the truck  12  by common fasteners, which may be self-tapping screws, bolts and nuts, rivets or the like. As the components are extrusions, the shape of the end views of each of the components reflects the full length of the structure. 
     As best seen in FIG. 2, the elongate frame members  22  include a base plate  30  with parallel elongate ribs  31  extending from one side thereof. The ribs  31  are at a 90° angle to the plane of the base plate  30  but could be equally rigid with other suitable shapes. An engagement surface  32  is located on the side of each rib  31  which is curved but shown to be overall at an acute angle to the base plate  30 . The curve of these engagement surfaces  32  is shown to provide an undercut portion to further enhance interlocking. The elongate frame members  22  also include a frame rail  33  having a frame rail surface  34 . The frame rail surface  34  faces roughly in the same general direction as the engagement surfaces  32 , i.e., away from the sheet  14 . 
     FIG. 6 illustrates a mortise bracket  23  which is employed as the upper attachment  20 . The mortise bracket  23  includes an attachment plate  24  for mounting the bracket  23  to the side of a truck  12  and a mortise  25  with an opening. The sheet  14  may be finished along the edge cooperating with the mortise  25  defined by a strip  26  formed with an attachment plate  27  and a bead  28 . The bead  28  is roughly circular in cross section with relieved areas  29  to either side of the plate  27  to reduce the concentration of stress during application and use. The bead  28  is preferably offset relative to the attachment plate  27 . This offset places the attachment plate  27  on a tangent to the bead  20 . The offset draws the sheet closer to the substrate. The bead  28  acts as a tenon in mounting the sheet  14  to the mortise  25 . The attachment plate  27  is RF welded or hot air welded to the sheet material. Other bonding techniques may be equally applicable. 
     The elongate attachments  20  are arranged in sets as noted above. The frame members  22  are each oriented such that the engagement surfaces  32  and the frame rail surface  34  of the elongate frame member  22  face away from the opposed attachment  20  of the same set. The same frame rails surfaces  34  are placed to face outwardly on the vertical elongate frame members  22 . 
     An elongate retainer  36  is illustrated separately in FIG.  3  and in combination with the elongate frame member  22  in FIG.  2 . This retainer  36  includes a base plate  38 . An elongate flange  40  is located along one edge of the base plate  38  and extends at an angle of approximately 60° from the plane of the base plate  38 . The elongate flange  40  includes an interlocking surface  42  on one side of the elongate flange  40 . The interlocking surface  42  is within the included angle between the elongate flange  40  and the plane of the base plate  38  and is curved to mate with the engagement surface  32 . 
     The elongate retainer  36  includes a retainer rail  44 , which has a retainer rail surface  46  on one side thereof. The retainer rail surface  46  faces away from the frame rail surface  34  when the elongate retainer  36  is assembled with the elongate frame member  22 . The base plate  38  is shown to extend in one direction from the elongate flange  40  and the retainer rail  44  with the elongate flange  40  and the retainer rail  44  extending in opposite directions from the plate  38 . 
     In addition to the elongate flange  40  and the retainer rail  44 , the elongate retainer  36  includes a portion  48  of the base plate  38  that has a thin, flexible wall that is attachable to the sheet  14 . The attachment may be by bonding or mechanical means but is most conveniently to be by RF welding or hot air welding between the sheet  14  and the portion  48  of the plate  38 . The portion  48  has at least a surface, and more conveniently the entire body, which is fusible to accommodate the RF welding. The thin, flexible nature of the portion  48  accommodates transition between the overall rigidity of the elongate retainer  36  and the flexible sheet. To further accommodate this transition, the elongate retainer  36  is coextruded of two materials, one more flexible and the other more rigid. The portion  48  of the plate  38  is formed from the flexible material. The elongate flange  40  and the retainer rail  44  are formed of the more rigid and dimensionally stable material. The material of the preferred embodiment is polyvinyl chloride (PVC), with the more flexible material having a density of 1.39 and the more rigid material having a density of 1.46. 
     FIG. 2 illustrates an association of one of the elongate frame members  22  and one of the elongate retainers  36 . The elongate flange  40  is shown extending between the ribs  31  such that the engagement surface  32  and the interlocking surface  42  are positioned in interlocking engagement. This engagement is with the sheet  14  in tension and extending away from the elongate retainer  36  from the portion  48  of the plate  38 . Naturally, the elongate flange  40  may be placed in any one of the slots defined between the ribs  31  to assure appropriate tension in the sheet  14 . 
     From FIG. 2 it can be observed that the elongate frame rail surface  34  on the frame  22  is facing away from the retainer rail surface  46  on the retainer  36 . These most adjacent rail surfaces  34  and  46  accommodate a tool. One such tool  50  is illustrated in FIG.  5 . The tool  50  includes a frame  52  rotatably supporting two sets of rollers. Each set includes two rollers  54  and  56 . The rollers  54  and  56  in each set define a pinch therebetween. The frame  52  mounts the rollers  54  on a first holder  58  and mounts the rollers  56  on a second holder  60 . The holders  58  and  60  include parallel guide dowels  62  and  64  and a parallel adjustment screw  66  used to move the rollers  54  and  56  to adjust the pinch. The rollers  54  and  56  are shown to be at an angle to one another. This allows the flanges on the rollers to ride on the rail surfaces  34  and  46 . 
     The two pinch rollers  54  and  56  are mutually displaced at the pinch to accommodate the size of the sheet  14 . The frame  52  is adjustable to place the sheet  14  in tension when the tool  50  has the rail surfaces  34  and  46  within the pinch of the rollers  54  and  56 . A slight over tension is appropriate to that which will be the final state of the sheet  14  in order that the tool  50  may place the elongate flange  40  in the slots between the ribs  31 . As the tool  50  moves forward with the flange  40  progressively located in one of the slots between the ribs  31 , the tension from the tool  50  is released and the engagement surface  32  and interlocking surface  42  come into interlocking engagement. 
     FIG. 4 illustrates a lock  68 . The lock  68  is illustrated in use in FIG.  2 . The lock  68  is defined as a channel which is extruded to have a uniform cross section along its length. The lock  68  is contemplated to be relatively short compared to the full length of the frame with several such locks  68  being put in place about any given frame. The channel includes a first leg  70  which interlocks with the retainer rail surface  46  when in position on the retainer. To accomplish this, the leg  70  is curved to create the engagement as illustrated in FIG. 2. A second leg  72  defining the channel extends to between the elongate flange  40  on the elongate retainer  36  and the next adjacent elongate rib  31 . The fit of the second leg  72  in this position is in interference to prevent extraction of the lock  68 . The lock  68  is preferably of a dimensionally stable PVC but may exhibit some compression at the end of the second leg  72 . The end of the second leg  72  includes flexible flanges  74  which extend laterally and are angled away from the end of the second leg. In this way, the end of the second leg  72  can be laterally compressible. 
     FIGS. 7 through 10 illustrate a system associated with a roll-up door  76 . The roll-up door is conventional in employing elongate panels  78  hinged together about axes parallel to those elongate panels. The panels run in tracks to either side of the door, usually with rollers. A sheet  14  is applied to the outer surface of such a roll-up door  76 . The difficulty is that the vertical length of the outer surface of such a door  76  increases while the door is rolled up. This increase is relatively small but results from the panels rotating to a horizontal position. Once one panel has done so, the extended length remains substantially constant. However, the vinyl sheet  14  is unable to accommodate this extension. 
     The sheet  14  is retained by an elongate attachment to a lower elongate panel  78  of the roll-up door  76 . Such an attachment may employ elongate frame members  22 . However, at the lower end of the sheet  14 , a tenon and mortise attachment as illustrated in FIG. 6 may be employed. The device illustrated in FIGS. 7 through 10 would then be employed at the upper end of the roll-up door  76 . 
     A roller mount  80  is attached to the elongate panel  78  on the back side of the roll-up door  76 . The mount  80  is shown to be bolted to the door by fasteners  82 . The mount  80  extends in this embodiment most of the way across the span of the elongate panel  78  that will be covered by the sheet  14 . An elongate frame member  22  is shown to be affixed to a mounting plate  84 . A sheet  14  with an elongate retainer  36  is draped over the top edge of the elongate panel  78  and down to be attached to the elongate frame member  22 . 
     To accommodate variation in the outer surface height of the door, roller assemblies adjust the path length of the mounted sheet  14 . The roller assemblies include roller mounts  86  slidably mounted relative to the inside surface of the upper panel  78  and rotatably mounting rollers  88  which then are biased to extend beyond the upper end of the door as illustrated in FIG.  7 . The roller mounts  86  include cylindrical retainers  90  which extend through holes  92  and  94  in plates  96  and  98 , respectively, formed as part of the roller mount  80 . These cylindrical retainers  90  are attached in pairs to a bottom plate  99  by fasteners  100 . The bottom plate  99  prevents the cylindrical retainers  90  from fully passing through the holes  94 . A top plate  102  is similarly arranged on the other end of pairs of cylindrical retainers  90  by fasteners  104 . The top plates  102  cooperate with the plates  96  on the roller mount  80  to retain compression springs  106 . These springs operate to bias the roller mounts into the extended position as shown in FIG. 7 while FIG. 8 illustrates the springs in compression when the sheet  14  is increased in tension because of the extension of the door while being rolled up or down. A support plate  108  is mounted to each top plate  102  to receive a rod  110 . The rod in turn mounts bearings  112  which rotatably support the rollers  88 . 
     In operation, a mortise bracket  23  is preferably mounted to the top of the side  10  of a truck  12  along the attachment plate  24 . If a roll-up door  76  is being used, the mortise bracket  23  may more conveniently be mounted to the lower portion of the door. As indicated above, the attachments  20  might be all provided by the elongate frames  22  rather than some by the mortise brackets  23 . The bottom of the panel  10  or the top inside surface of a roll-up door  76  is fitted with an elongate frame  22 . In the case of the roll-up door, the roller bracket and assembly and are also mounted in place by the fasteners  82 . When all four edges of a sheet  14  are to be anchored, an additional set of attachments  20  are mounted vertically. 
     A sheet  14  is prepared by RF welding strips  26  along the edges of the sheet  14  to be attached. The strips  26  may include beads  28  for receipt by a mortise bracket  23  or for receipt of a retainer as disclosed in U.S. Pat. No. 6,276,082 or may be elongate retainers  36 . The first edge of the sheet  14  is placed in a first attachment. This normally would include positioning a bead  28  in a mortise  25  by threading one into the other. The tool  50  is then used to zip the retainer or the elongate retainer  36  in place under tension on an appropriately spaced rib by pinching the rails  33  and  44  and moving the interlocking surface  42  laterally into engagement with the engagement surface  32 . Locks  68  are then installed over the retainer rails  44  to complete the installation. 
     Thus, an improved mounting system is disclosed for large sheet material. While embodiments and applications of this invention have been shown and described, it would be apparent to those skilled in the art that many more modifications are possible without departing from the inventive concepts herein. The invention, therefore is not to be restricted except in the spirit of the appended claims.