Abstract:
A vehicle tonneau system having a flexible fabric cover and a rail system having flanges attached to a vehicle for mounting the flexible fabric cover in which elongated fasteners for attaching the flexible cover to the rail flanges are provided with a hinging portion. A portion of the fastener is pivoted about the hinging portion which eases the initial removal of the fastener. Once a distal end of the fastener is moved past a terminal edge of the rail flange, the remainder of the fastener easily peels from the frame, by lifting the flexible fabric cover.

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     The present invention relates generally to flexible tonneau covers for vehicles and in particular to an improved release for removing a tonneau cover that uses an extruded j-strip or hook fastener along the edge of the flexible tonneau cover to attach the cover fabric to the vehicle. 
     Tonneau covers are generally defined as any device which can be used to cover a portion of a vehicle. While tonneau covers are generally used to cover convertible cars, boats and trailers, tonneau covers are most commonly associated with pick-up trucks. Both rigid and flexible tonneau covers are available for covering the cargo box of pick-up trucks. The present invention relates to flexible tonneau covers. 
     Flexible tonneau covers for pick-up trucks typically include a rectangular frame made of extruded aluminum rails which are attached to the pick-up truck at the top of the cargo box. A flexible fabric cover is then attached to the rails to cover the cargo box. The fabric is generally a woven material with a vinyl coating. The term “fabric” is used throughout this specification in the broad sense to mean a flexible sheet material and is not limited to a woven material. 
     One mechanism used to attach the flexible fabric to the frame is a j-strip or elongated hook shaped fastener attached along the edge of the flexible fabric. The j-strip or fastener is wrapped around a flange formed in the frame for the purpose of mounting the fabric. The cover is removed from the frame by lifting the fabric off of the frame, beginning at one corner and peeling the fastener from the flange formed in the frame along each edge of the fabric. In some situations, particularly in cold weather, it can be difficult to begin the initial removal of the fastener from the frame at the corner of the cover. This difficulty in removing the fastener in cold temperatures is caused by fabric shrinkage and increasing stiffness in the j-strip or hook shaped fastener. Once an initial portion of the j-strip or hook shaped fastener is removed from the frame, the fastener will easily peel along the entire length of the cover. 
     It is an object of the present invention to provide a mechanism for easing the removal of the fastener and fabric from the frame, while at the same time maintaining a tight fit of the fabric on the frame. 
     Another object of this invention is to provide a mechanism for easing the mounting of the fastener and fabric to the frame. 
     The present invention eases the mounting and removal of the j-strip or fastener from the frame by providing a j-strip or hook shaped fastener with a hinge, notch, score, groove or crease formed therein. The hinge, notch, score, groove or crease formed in the j-strip or fastener allows the base of the fastener to be bent, pivoting the hook of the fastener away from the base of the fastener and thus away from the flange of the rail to aid in the release of the fastener. This bending of the hook relative to the base operates to widen or open the throat of the hook. In addition to widening or opening the throat of the hook, the enhanced bending action of the hook reduces the distance from the bottom or curve of the hook to the tip of the hook. This reduces the distance by which the fastener must be moved, relative to the flange formed in the frame, to achieve the initial fastener removal. Once an initial edge of the fastener is moved past the terminal edge of the flange formed in the frame, the remainder of the fastener will easily peel from the frame by lifting the fabric from the rail. By providing a hinge, notch, score, groove or crease in the fastener, less force is required to achieve removal of the fastener. 
     The hinge is positioned in the base of the fastener on the opposing side from which the hook extends. Preferably, the hinge is located either substantially opposite a merger point of the hook and the base or above the merger point in the direction of the hook&#39;s distal end. The latter positioning being the more preferred positioning. 
     Further objects, features and advantages of the invention will become apparent from a consideration of the following description and the appended claims when taken in connection with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a pick-up truck cargo box with the tonneau cover of the present invention installed thereon; 
     FIG. 2 is a sectional view of the tonneau cover frame and attachment for mounting the tonneau cover to the pick-up truck cargo box; 
     FIG. 3 is an enlarged sectional view of the fastener and frame showing the fastener being removed from the frame; 
     FIG. 4 is an enlarged side elevational view of a first embodiment of the fastener of the present invention; 
     FIG. 4A is an enlarged side elevational view of a second embodiment of the fastener of the present invention; 
     FIG. 5 is a partial perspective view of the fastener as seen in FIG. 4; 
     FIG. 6 is a partial perspective view of the fastener as seen in FIG. 5, with the tab being deflected for removing the fastener from the rail; and 
     FIGS. 7,  8  and  9  are perspective views illustrating the process of removing the cover, having a fastener as seen above attached thereto from the frame, the process of mounting the cover to the frame being generally the reverse thereof. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following description of the present invention is merely exemplary in nature and is in no way intended to limit the invention or its uses. Moreover, the following description, while depicting a fastener designed to operate with a particular rail system, is intended to adequately teach one skilled in the art to make and use a fastener for any similar rail system including those which clamp through a stake box. 
     A tonneau cover system  10  of the present invention is shown in FIGS. 1 and 2 mounted upon a cargo box  12  of a pick-up truck  14 . The tonneau cover system  10  includes a frame  16 , only a portion of which is visible in FIG. 1, which is clamped to an upper end of a side wall  22  of the cargo box  12  by a plurality of clamps  18 . A flexible fabric cover  20  is attached to the frame  16  so as to cover the opening of the cargo box  12 . 
     The side wall  22  of the cargo box  12  has an upper surface  24  upon which the frame  16  is disposed. The frame  16  is constructed of a plurality of elongated rails  26  which are joined together at their ends to form a rectangular frame sized to fit on the cargo box  12 . The rails  26  are typically made of extruded aluminum and are substantially uniform in cross section along their entire lengths. The rails  26  have a slot  28  on the inboard side into which an upper portion  30  of a first clamp member  32  is positioned and is slidable along the length of the rails  26 . A second clamp member  34  is attached to the first clamp member  32  by a nut and bolt assembly  36  and traps a down turned flange  38  of the side wall  22  of the cargo box  12  between the clamp members  32 ,  34 . This secures the clamp  18  to the side wall  22  of the cargo box  12  and in turn secures the frame  16  to the cargo box  12 . A foam rubber tape  40  is attached to the bottom of the rail  26  to provide a protective seal between the rail  26  and the upper surface  24  of the cargo box  12  which aids in preventing scratching or marring of the cargo box finish by the aluminum rail  26 . It is also contemplated that the rails be mounted to the inside of the cargo box and that a pair of rails be utilized as opposed to a rectangular frame. 
     The rail  26  includes an outboard slot  42  formed by a flange  44  which extends generally away from the interior of the cargo box  12 . The flange  44  has a terminal or distal edge  46 . The fabric cover  20  is attached to the flange  44  of the rail  26  by a j-strip or hook shaped fastener  50  described below. 
     The j-strip or hook shaped fastener  50 , best seen in FIGS. 3-6, is an elongated extrusion which is attached to the fabric cover  20  along the edge thereof. The fastener  50  has a base portion  52  which is generally planar and rests against an inner surface  21  of the fabric cover  20 . The base portion  52  terminates at one end in a tab  70 . The base portion  52  is sewn to the fabric cover  20  with a pair of seams. A hook portion  56  of the fastener  50  includes a return bend which extends from the base portion  52  in a direction away from and on a side opposite of the fabric cover  20 . The hook portion  56  turns generally toward the central region of the fabric cover  20  forming a bight  58  with a concave inner surface  60 , and terminating in a distal end  62 . The hook portion  56  has a nominal length L measured from the base portion  52  to the distal end  62 . The concave inner surface  60  may be cylindrical or acylindrical. In the first embodiment of the fastener  50  shown in FIG. 4, the bight  58  has a generally cylindrical shape. In the second embodiment of the fastener  50  shown in FIG. 4A, the bight  58 ′ has a “raked” shape defined by three separate radii of curvature. Proceeding along the concave inner surface  60  to the distal end  62 , the first radius of curvature is greater than both the second and third, while the third radius of curvature is greater than the second. This raked shape of the bight  58 ′ as shown in FIG. 4A allows the hook portion  56  to more quickly open and release from the flange  44  of the rail  26 . The hook portion  56  intersects the base portion  52  at a merger point  63 . 
     A hinge  53 , formed in the base portion  52  of the fastener  50  as a notch, score, groove or crease, allows the hook portion  56  and the tab  70  to be manually pivoted which operates to widen or open the bight  58  of the hook portion  56 , thereby aiding in the release of the hook portion  56  from the flange  44  of the rail  26 . 
     In FIG. 4, the hinge  53  is illustrated as a radiused groove and is located opposite the hook portion  56  and the merger point  63 . In an alternate embodiment, FIG. 4A illustrates the hinge  53 ′ in a position opposite the hook portion  56 , and forward of the bight  58 ′ and the merger point  63 . The location of the hinge  53 ′ as shown in FIG. 4A is such that it begins at the center of the distal end  62  and terminates at a point farther away from the bight  58 ′. The shape of the hinge  53 ′ shown in FIG. 4A differs from that shown in FIG.  4  and may be described as a slot with 90° corners. Obviously, other cross-sectional shapes for the hinge  53  may be used as well. Two such shapes, in addition to those previously mentioned, include partially round and V-shaped. Other shapes can readily be envisioned. 
     Preferably, the hinge  53  extends the entire length/width of the fastener  50 . It is possible, however, that the hinge  53  could be formed over less than the entire length/width of the fastener  50 . 
     The fastener  50  is mounted to the rail  26  by pulling on the fabric cover  20  and placing the bight  58  of the hook portion  56  around the terminal edge  46  of the flange  44  of the rail  26 . This seats the terminal edge  46  of the flange  44  into the bight  58 , contacting the concave inner surface  60  along a line of contact  84  (shown in FIGS. 5-9) which extends the length of the fastener  50  and the rail  26 . This line of contact  84  is generally at the deepest point of the concave inner surface  60  of the bight  58  and is spaced from the distal end  62  of the hook portion  56 . 
     The base portion  52  of the fastener  50  extends rearward, beyond the hook portion  56 , forming the tab  70 . The fastener  50  is removed from the rail  26  by applying a force on the tab  70  in the direction of the arrow  72  as shown in FIGS. 3,  6 ,  8  and  9 . With reference to FIGS. 7,  8  and  9 , the progressive removal of the fastener  50  from the flange  44  of the rail  26  is shown in sequence. 
     The force applied in the direction of the arrow  72  is generally normal to the plane of the base portion  52  and the rail flange  44 . The force applied in the direction of the arrow  72  causes the hook portion  56  and the tab  70  to pivot about the hinge  53  as shown in FIG.  6 . This in turn widens or opens the bight  58  of the hook portion  56  slightly, allowing the line of contact  84  between the terminal edge  46  of the flange  44  and the bight  58  of the hook portion  56  to move gradually toward the distal end  62  of the hook portion  56 . Further movement of the tab  70  of the fastener  50  in the direction of the arrow  72  causes the distal end  62  of the fastener  50  to clear the terminal edge  46  of the flange  44 , thereby freeing the fastener  50  and the fabric cover  20  from the rail  26 . The remainder of the fastener  50  and the fabric cover  20  will peel from the rail  26  as shown in FIG. 9 by continued lifting of the fastener  50  from the rail  26  along the entire length of the rail  26 . 
     Generally, as stated above, removal of the fabric cover  20  is accomplished by starting at one corner of the tonneau cover system  10  and first removing the fastener  50  from the rail  26  at the end of the fastener  50 . After an initial end portion of the fastener  50  is released from the rail  26 , the remainder of the fastener  50  will easily peel away from the rail  26  by lifting the fabric cover  20 . The greatest force is needed to initially move the hook portion  56  of the fastener  50  off the flange  44  of the rail  26 . 
     In cold temperatures, the fabric cover  20  shrinks and the fastener  50  stiffens. This increases the force required to initially remove the fastener  50  from the rail  26 . The above-described hinge  53  aids in facilitating removal of the fastener  50  from the rail  26  under such conditions. 
     The present invention provides a tonneau cover system  10  which eases the removal of the fabric cover  20  from the flange  44  of the rail  26  by providing a fastener  50  having a hinge  53 . The fastener  50  including the hinge  53  reduces the force required for initiating the removal of the fastener  50 . 
     It is to be understood that the invention is not limited to the exact construction illustrated and described above, but that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.