Abstract:
A tonneau system for a cargo box of a vehicle including a support frame, a cover spanning the support frame; and a clamp. The support frame includes side rails having an inboard section and an outboard section, such that the outboard section is positioned adjacent to the top surface of the sidewall of the cargo box to aid in the supporting and positioning of the support frame. The clamp is capable of hanging from the support frame during installation to improve the ease thereof. The clamp also includes a pair of members being positionable in any one of a plurality of discrete positions for improved installation. A front rail adjustment mechanism permits the selective tensioning of the cover to maintain a predetermined load therein. While a front rail retaining mechanism is slidably coupled to the front rail member to prevent the front rail member from being inadvertently disengaged from the side rail members. A rear rail retaining mechanism is used to lock the rear rail member or unlock the rear rail member and urge the rear rail member upward.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional application of U.S. patent application Ser. No. 10,331,711, filed Dec. 30, 2002 now U.S. Pat. No. 6,752,449. The disclosure of the above application is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention generally relates to coverings for pickup trucks and, more particularly, relates to a roll up tonneau cover system. 
     BACKGROUND OF THE INVENTION 
     Tonneau covers have been used for a number of years to cover the cargo box of pickup trucks against dirt, debris, and other environmental contaminants and to improve the aesthetic quality thereof. Originally, tonneau covers were designed by upholstery shops and typically made of vinyl covered fabrics or canvas. The material was often doubled over along its edges for added strength and appearance. Male snaps were then attached to the sides of the cargo box of the pickup truck via fasteners, while female snaps were attached along the edges of the cover. Wooden bows were sometimes used to span the cargo box and ensure that the cover remained high enough to drain water. Unfortunately, these covers were sometimes difficult to handle, often led to corrosion around the snaps, and occasionally failed to protect the cargo box. 
     However, in the ‘70&#39;s, in an attempt to overcome the corrosion around the snaps, tonneau rails were removably mounted to the cargo box of the pickup truck using clamps. These tonneau rails carried the aforementioned snaps and, thus, eliminated the need to mount the snaps directly to the walls of the cargo box. 
     With the advent of the VELCRO® hook-and-loop fastening system, tonneau cover systems were developed that included gluing one of the hook or loop strips to the pickup truck and sewing the other strip to the fabric tonneau cover material to effect a simple connection without altering the vehicle body. An example of this system is shown in U.S. Pat. No. 4,272,119, issued to Adams. The disclosure of which is hereby incorporated and made a part of this application by reference. However, the tonneau cover of Adams had a problem remaining attached near the front of the cargo box, most likely due to wind forces. This problem was overcome using a rod of stiff rope or fiberglass sewn into a flap along the front of the tonneau cover. This rod was received within a channel having a “bite” mounted near the front of the cargo box to retain the tonneau cover in an attached position. 
     Rotating rails were later developed to fasten and tighten a tonneau cover. One such system employed two side rails running longitudinally down the sides of the cargo box of the pickup vehicle. A second rail was pivotally attached to each of the two side rails and carried the fabric tonneau cover such that upon downward rotation of the second rails, the fabric tonneau cover was pulled tight. The second rails were then locked in connection with the side rails. This system further included VELCRO® fasteners along the front and rear edges and a zipper for separating left and right halves. An example of this system can be seen in U.S. Pat. No. 4,036,521, issued to Clenet. The disclosure of which is hereby incorporated and made a part of this application by reference. 
     Similar to the above system, a tongue and groove connector system is also known for detachably fastening a stretchable fabric panel to a rigid frame. The tongue and groove connector system included a tongue-forming element attached along a line intermediate the side edges thereof to the stretchable fabric panel. The tongue being insertable into a groove with a projecting portion extending there beyond which defines a handhold. The connection requires the fabric to be stretched to a point where the leading edge of the tongue lies adjacent the entryway into the groove such that the stretched fabric pulls the tongue into seated relation in the bottom of the groove. An example of this system can be seen in U.S. Pat. No. 4,757,854, issued to Rippberger. The disclosure of which is hereby incorporated and made a part of this application by reference. 
     Similarly, the convertible boot cover for the 1980 FORD® Mustang includes a trim strip around a boot having a slot for inserting a polymer tongue that is sewn to the cover. The tongue is toggled into the slot providing an attachment for the cover. This attachment is similar to that of Rippberger &#39;854. 
     Further development of tonneau systems led to the use of 45° angled frame rails to improve the aesthetic quality of the tonneau cover. The angled frame rails carried a snap connector for retaining the tonneau cover material. Often, these systems included a double layer of tonneau cover material in the region of the snaps for added reinforcement. Such systems also included a clamp system for coupling with the sidewalls of the cargo box. One such clamp system used a clamp that “bottomed out” to prevent over stressing the sidewalls of the cargo box. Examples of these systems can be seen in U.S. Pat. Nos. 4,730,866 and 4,838,602, issued to Nett. The disclosures of which are hereby incorporated and made a part of this application by reference. 
     Many of these previous features were incorporated in later designs with slight modifications. For example, U.S. Pat. No. 5,076,338, similar to U.S. Pat. No. 4,036,521, employed a pivoting rail to tighten the tonneau cover material. In this particular system, an “L” shaped rail, which presumably puts the pivot lower for added mechanical advantage, was used to tighten the tonneau cover material from a fore and aft position, rather than cross-car position. This system further employed the 45° angled frame rails and VELCRO® fasteners. The frame rails are coupled to the sidewalls of the cargo box using a plurality of C-clamps. Furthermore, the system included a double layer of tonneau cover material in the region of the snaps for added reinforcement as seen in previous designs. 
     In a more recent design, a rotating rear rail was provided that included positioning the pivot near the upper surface of the tonneau to minimize torque exerted on the rear rail. The lower torque of this system permitted the use of relatively lightweight plastic levers to lock the rear rail and prevent it from rotating. The combination of the length of these plastic levers and high pivot locations enabled the loads exerted on the levers to be about {fraction (1/12)}th that of the tonneau cover material. Springs were also taught that enabled the automatic tensioning of the tonneau cover material. An example of this system can be seen in commonly owned U.S. Pat. No. 5,251,951, issued to Wheatley. The disclosure of which is hereby incorporated and made a part of this application by reference. 
     Relatively recently, a tonneau cover system having a screw adjustment mechanism was developed for permitting the fore and aft adjustment of the front rail. This screw adjustment mechanism serves to tighten the tonneau cover material in response to wear and/or stretch that is common in tonneau cover systems. The tonneau cover system further employed the “L” shaped lever and lower-positioned pivot, which unfortunately requires the lever to carry an enormous amount of force. That is, by way of example, assuming a 1″ thick rail with a ½″ offset to the latching pivot, a 30-pound tarp load will impart a 60-pound load on the lever. Consequently, a stronger latch is required to overcome these loading forces and minimize wear and breakage. Frame rails are coupled to the sidewalls of the cargo box using a plurality of C-clamps. An example of this system can be seen in U.S. Pat. No. 5,906,407, issued to Schmeichels. The disclosure of which is hereby incorporated and made a part of this application by reference. 
     A TRUXEDO cover, which is not believed to be patented, made by SHURCO includes a rotating, rectangular, rear rail having a rounded front pivot, vertical sides with VELCRO® attachment, and spring pins that push on a front rail mounted inboard of the side rails. These spring pins push against the front rail to tension the system in the fore-aft direction. The spring pins, which are attached to the side rails via brackets, may not firmly engage the front rail due to their inboard location which may cause the brackets to come out of alignment as the side rails rotate. Additionally, the rounded shape of the front rails may cause the push pins to slip off-center. 
     Lastly, U.S. Pat. No. 6,293,608, issued to Dicke, et al., discloses a tailgate rail interconnected to side rails with an interconnecting plate fixedly coupled to the side rails and slideably coupled to the corner piece for accommodating relative movement therebetween. A biasing device, being a coil spring, is further provided. This system provides tensioning to the tonneau fabric. 
     SUMMARY OF THE INVENTION 
     According to the principles of the present invention, a tonneau system for a cargo box of a vehicle having an advantageous construction is provided. The tonneau cover system includes a support frame, a cover spanning the support frame, and a clamp. The support frame includes side rails having an inboard section and an outboard section, such that the outboard section is positioned adjacent to the top surface of the sidewall of the cargo box so as to aid in the supporting and positioning of the support frame. The clamp is capable of hanging from the support frame during installation to improve the ease thereof. The clamp also includes a pair of members being positionable in any one of a plurality of discrete positions for improved installation. A front rail adjustment mechanism permits the selective tensioning of the cover to maintain a predetermined load therein. While a front rail retaining mechanism is slidably coupled to the front rail member to prevent the front rail member from being inadvertently disengaged from the side rail members. A rear rail retaining mechanism is used to lock the rear rail member or unlock the rear rail member and urge the rear rail member upward. 
     Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
     FIG. 1 is a perspective view illustrating a pickup truck having a tonneau cover system according to the principles of the present invention; 
     FIG. 2 is a cross sectional view illustrating the frame rail assembly taken along line  2 — 2  of FIG. 1; 
     FIG. 3 is a plan view illustrating the front rail member and frame rail assembly; 
     FIG. 4 is a partial cross sectional view illustrating the front rail member and frame rail assembly taken along line  4 — 4  of FIG. 3; 
     FIG. 5 is a partial cross sectional view illustrating the front rail member and frame rail assembly taken along line  5 — 5  of FIG. 3; 
     FIG. 6 is a perspective view illustrating the retaining mechanism; 
     FIG. 7 is a partial cross sectional view illustrating the rear rail member and frame rail assembly shown in a locked position; 
     FIG. 8 is a partial cross sectional view illustrating the rear rail member and frame rail assembly shown in an intermediate position; and 
     FIG. 9 is a partial cross sectional view illustrating the rear rail member and frame rail assembly shown in an unlocked and upwardly urged position. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     With reference to FIG. 1, a pickup truck  10  is shown having a roll up roll up tonneau system  12  which is attached to a cargo box  13  according to the present invention. Cargo box  13  has a front wall  14 , a left sidewall  16 , a right sidewall  18 , and a rear wall or tailgate  20 . Roll up roll up tonneau system  12  includes a flexible, stretchable fabric cover  22  that is drawn tightly over a substantially rigid rail support system  24  and removably attached to rail support system  24 . Rail support system  24  is comprised of a number of frame rails that are attached to one another to form a rectangular frame. The frame rails included are a front frame rail or head rail assembly  26 , a left side frame rail assembly  28 , a right side frame rail assembly  30 , and a rear frame rail assembly  32 . Rail support system  24  is aligned with the top of sidewalls  16  and  18  of cargo box  13  as well as the top of front wall  14  and tailgate  20 . 
     It should be understood that right sidewall  18  and left sidewall  16  of pickup truck  10  and the corresponding right side frame rail assembly  30  and left side frame rail assembly  28  are identical in construction, yet arranged in mirrored symmetry. Accordingly, in the interest of brevity, only one side will be discussed in detail below unless noted otherwise. 
     As best seen in FIG. 2, right side frame rail assembly  30  is coupled to right sidewall  18  of cargo box  13  of pickup truck  10 . As can be seen, sidewall  18  of cargo box  13  includes a generally horizontal top surface  34  and a downwardly extending inside wall  36 . However, it should be appreciated that generally horizontal top surface  34  and downwardly extending inside wall  36  may have any one of a number of configurations, which are dependent upon styling and functionality determined by the vehicle manufacturer. Hence, it should be understood that the particular shape of these surfaces/walls may vary, along with the specific shape of those corresponding components of frame rail assembly  30 . 
     Still referring to FIG. 2, frame rail assembly  30  generally includes a support bracket  38 , a hanging side member  40 , and a back member  42 . Support bracket  38  includes a first horizontal portion  44  having a channel  46  formed therein. Channel  46  is generally defined by a pair of upturned and inwardly projecting flanges  48 . Channel  46  is sized to receive one of a cooperating pair of strips of a hook-and-loop fastener system  49 —that is, a first strip  50  of the pair is disposed in channel  46  and the corresponding second strip  51  of the pair is mounted on fabric cover  22 . Preferably, the hook-and-loop fastener system is made of VELCRO®. However, it should be understood that alternate suitable fasteners may be used, such hook and hook material, other self-adhesive material, magnetic tape on steel, tongue and groove, and the like. Frame rail assembly  30  further includes a downwardly extending portion  52  that terminates into a second horizontal portion  54 . Second horizontal portion  54  is adapted to support an adjustment mechanism that will be discussed in detail below. 
     With continued reference to FIG. 2, frame rail assembly  30  still further includes a second downwardly extending portion  56  extending from an intermediate section of first horizontal portion  44  generally adjacent inside wall  36  of sidewall  18 . Second downwardly extending portion  56  receives a flat seal  58  preferably adhesively coupled thereto. Flat seal  58  is adapted to engage inside wall  36  of sidewall  18  to define a fluid sealing connection therebetween. Flat seal  58  may be made of any suitable material that would at least inhibit inflow of water, dirt, debris, or other environmental contaminants. 
     To further prevent the influx of water, dirt, debris, or other environmental contaminants from entering cargo box  13  through the interface between support bracket  38  and sidewall  18 , a second seal  60  is provided. Specifically, as can be seen in FIG. 2, first horizontal portion  44  extends outboard such that an overlapping outboard section  62  overlaps a portion of top surface  34  of sidewall  18  while an inboard section  63  cantilevers inward into cargo box  13 . Second seal  60  is preferably D-shaped and extends downwardly from overlapping outboard section  62  such that second seal  60  compressibly engages top surface  34  of sidewall  18 . 
     The overlap of overlapping outboard section  62  relative to top surface  34  provides a number of useful advantages over the prior art. Specifically, such overlapping relationship between support bracket  38  and sidewall  18  defines a positive positioning reference during installation of roll up tonneau system  12 . Additionally, the weight exerted on support bracket  38  causes second seal  60  to be further compressed against top surface  34  of sidewall  18 , thereby further ensuring a reliable sealing connection. Still further, the use of flat seal  58  and second seal  60  provide a double sealing connection along both horizontal and vertical surfaces. Unlike the prior art that seals only along a vertical surface, the present invention does not readily permit water to lie upon the vertical sealing surface, which considerably improves the sealing characteristics. 
     Turning now to the clamping system of the present invention, hanging side member  40  and back member  42  cooperate to retain support bracket  38  to sidewall  18 . In particular, hanging side member  40  is shown being generally planar in construction with a hooked flange  64  formed on an upper end  66  and a series of alignment depressions  68  formed on an opposing end  70 . Hooked flange  64  is sized to cooperate with a corresponding flange  72  extending upwardly from second downwardly extending portion  56  so that hanging side member  40  can hang from second downwardly extending portion  56  during installation. Hanging side member  40  further includes an aperture  73  formed therein to receive at least one fastener  74 . 
     Back member  42  is shown being generally U-shaped in construction having an alignment head  76  formed on a lower end  78  and an engaging head  80  formed on an upper end  82 . Alignment head  76  is preferably curved in shape and sized to be received within one of the series of alignment depressions  68 . Engaging head  80  preferably includes a pair of outwardly extending flanges  84  adapted to retain a contact member  86 . Contact member  86  is preferably made of a soft rubber material to prevent damage to inside wall  36  of sidewall  18 . However, contact member  86  is optional and, thus, may be eliminated or replace with other material. Still further, back member  42  includes a retaining nut  88  that cooperates with fastener  74  to apply a clamping force upon inside wall  36  of sidewall  18  to retain support bracket  38  in position. Retaining nut  88  is preferably held by retaining flanges  90 , which serve to hold retaining nut  88  in position and fixed against rotation. However, it should be understood that other fastener systems may be used, such as a quick release clamping mechanism or other known means. 
     During clamping, back member  42  is first loosely fastened to hanging side member  40  via fastener  74  and retaining nut  88 . Hanging side member  40  is then conveniently inserted such that hooked flange  64  engages corresponding flange  72  to permit hanging side member  40  and back member  42  to hanging from such position. By maintaining hanging side member  40  and back member  42  in a loosely fitting arrangement, back member  42  may be positioned along a backside of inside wall  36 . Back member  42  may also be positioned vertically relative to hanging side member  40  by moving alignment head  76  into one of the series of alignment depressions  68 , thereby adjusting the position of contact member  86  upon inside wall  36 . In order to facilitate such adjustment, it can be seen that aperture  73  formed in hanging side member  40  is preferably a slot to permit the vertical translation of fastener  74  relative to hanging side member  40 . Fastener  74  is then tightened to apply a clamping force upon inside wall  36  to retain support bracket  38  in position and further compress flat seal  58 . It should be appreciated that the present arrangement simplifies installation of roll up tonneau system  12  in that the clamping mechanism need not be held in place by a user with one hand while simultaneously tightening fastener  74  with the other hand, as required in the prior art. Additionally, due to the hanging feature of hanging side member  40  and overlapping outboard section  62  of first horizontal portion  44 , frame rail assembly  30  can not be easily removed from pickup truck  10  nor will the clamping mechanism fall out of position or tonneau cover  22  drop down should fastener  74  become loosened. 
     Turning now to FIGS. 3-9, head rail assembly  26  will now be discussed in detail. As best seen in FIG. 3, head rail assembly  26  generally includes a forward rail member  92  that extends in the cross-car direction generally in plane with front wall  14  of cargo box  13 . Forward rail member  92  receives an attachment member  94  coupled to fabric cover  22  within a receiving channel  96  formed in an upper surface of forward rail member  92  to define the forward edge of coverage of roll up tonneau system  12 . Receiving channel  97  formed in forward rail member  92  receives a bulbous seal  99  that has a first portion  105  disposed in receiving channel  97 , a second D-shaped portion  103  coupled to first portion  105 , and a downwardly biased, curved wiper seal  101  that engages the top of front wall  14  to provide a sealing engagement therebetween. Forward rail member  92  is preferably hollow to minimize weight and generally rectangular in cross section. At an end opposing receiving channel  96 , forward rail member  92  includes a generally curved portion  98 . Generally curved portion  98  is adapted to engage a corresponding curved channel  100  disposed at a forward end of an adjustment support bracket  102 . A recess  104  is formed above generally curved portion  98  on forward rail member  92  to prevent interference with a protruding flange  106  extending from adjustment support bracket  102 . Accordingly, when fabric cover  22  is installed above rail support system  24 , generally curved portion  98  of forward rail member  92  may be inserted into curved channel  100  in an inclined position and then rotated forward relative to the vehicle into the illustrated lowered position. During this movements generally Curved portion  98  smoothly rotates with curved channel  100 . 
     As best seen in FIGS. 5 and 6, in order to retain forward rail member  92  in this lowered position, a retaining mechanism  108  is provided. Retaining mechanism  108  includes a latch member  110  slidably coupled to forward rail member  92  via a fastener  112 , such as a thumb screw, and nut  114 , such as an elongated nut or T-nut. Nut  114  is slidably retained with a lower C-shaped channel  116  (FIG. 4) extending along an underside of forward rail member  92 . Latch member  110  includes a cantilevered portion  118  adapted to be positioned adjacent an underside of second horizontal portion  54  of support bracket  38  to prevent the removal of forward rail member  92  relative to support bracket  38 . Retaining mechanism  108  further includes a guide locator  120  having a screw  122  retaining a fixed locator  125 . It should be understood that guide locator  120  may be made integral with latch member  110 . Lastly, a plurality of steps  123  are disposed along the upper side of latch member  110  to provide the necessary spacing of cantilevered portion  118  from second horizontal portion  54 . 
     Referring again to FIGS. 3 and 4, an adjustment mechanism  124  is provided for engagement with forward rail member  92  to selectively position forward rail member  92  in a further fore or aft position to adjust the tightness of fabric cover  22 . This preferred position of forward rail member  92  may vary depending upon installation, age of fabric cover  22 , environment temperatures and moisture levels, and the like. To effect such adjustment, adjustment mechanism  124  includes adjustment support bracket  102  that is fixedly coupled via conventional methods to second horizontal portion  54  of support bracket  38 . Adjustment support bracket  102  is generally box-shaped having protruding flanges  106  extending from a forward end thereof. 
     Adjustment support bracket  102  further includes an adjustment bolt  126  having a head portion  128  and an engaging portion  130 . Head portion  128  extends beyond an aft end of adjustment support bracket  102 , while engaging portion  130  engages forward rail member  92 . Specifically, engaging portion  130  engages a generally flat portion  132  formed in curved portion  98  to mate with engaging portion  130  of adjustment bolt  126 . It should be noted that generally flat portion  132  might include a lower edge  134  that is held by engaging portion  130  of adjustment bolt  126 , which aids in retaining forward rail member  92  in a lowered position. 
     Adjustment mechanism  124  further includes a nut  136 , which is preferably a wing nut having wings that engage interior side surfaces  138  of adjustment support bracket  102  to prevent nut  136  from rotating relative to adjustment support bracket  102 . A spring  140  extends between nut  136  and an interior end surface  142  of adjustment support bracket  102  to providing a biasing force against nut  136 . The length of spring  140  is chosen such that the shrinkage or expansion with temperature of fabric cover  22  will not cause the spring force to vary greatly, thus maintain the tension in fabric cover  22  nearly constant. Accordingly, as adjustment bolt  126  is driven inward (forward), engaging portion  130  is driven in contact with generally flat portion  132  of forward rail member  92 , thereby driving forward rail member  92  forward. Further forward displacement of forward rail member  92 , and corresponding fabric cover  22 , continue until the tension in fabric cover  22  generally equals the biasing force of spring  140 . Therefore, according to the present arrangement, fabric cover  22  is ensured to remain taut, even during environment temperature and moisture changes and age. However, should further adjustment of fabric cover  22  be necessary, adjustment bolt  126  may simply be further driven forward. 
     Although, as seen in FIGS. 3 and 4, an adjustment limit  144  may be used to prevent excessive adjustment of forward rail member  92  in either the fore or aft direction. To this end, adjustment limit  144  includes a bolt  146  coupled to a nut  148  disposed in lower channel  116  of forward rail member  92 . Bolt  146  downwardly extends and is received with an aperture  150  formed in second horizontal portion  54  of support bracket  38 . By way of non-limiting example, it is anticipated that adjustment limit  144  would limit the adjustment of forward rail member  92  to within about 1″ of fore and aft movement. Furthermore, aft movement is limited by the interface between curved portion  98  and corresponding curved channel  100 . Adjustment limit  144  prevents forward rail member  92  from sliding forward when fabric cover  22  is rolled up into a forward open position at the front of cargo box  13 . When fabric cover  22  is in the closed position, the combination of biasing force from spring  140  and inherent tension within fabric cover  22  maintains adjustment limit  144  and forward rail member  92  in proper position. 
     As best seen in FIG. 3, each support bracket  38  preferably receives a pair of bumper members  141  disposed on opposing ends of support bracket  38  in a space defined by first downwardly extending portion  52 , a portion of first horizontal portion  44 , and second downwardly extending portion  56 . Bumper member  141  preferably has a plurality of retaining ridges  143  to engage first downwardly extending portion  52 , a portion of first horizontal portion  44 , and second downwardly extending portion  56  to maintain bumper member  141  within the aforementioned space. Each of the pair of bumper members  141  includes a head portion  143  and a base portion  145 . Head portion  143  engages front wall  14  or tailgate  20 , while base portion  145  is received in the defined space. Once installed, bumper members  141  engage front wall  14  or tailgate  20  of pickup truck  10  and act to align, maintain, and hold support bracket  38  and, thus frame rail assembly  30  in a generally centered fore-aft position. Furthermore, bumper members  141  further serve to properly position seals  103  and  161  relative to front wall  14  and tailgate  20 , respectively. 
     Turning now to FIGS. 7-9, a rear latching mechanism  152  will be described in detail. As can be seen in the figures, rear latching mechanism  152  shares a number of parts with head rail assembly  26 . In particular, rear-latching mechanism  152  includes the aforementioned forward rail member  92 , referenced as rear rail member  92 ′ hereinafter, and adjustment support bracket  102 , referenced as support bracket  102 ′ hereinafter. It should be appreciated that such use of members in multiple locations within roll up tonneau system  12  provides a number of manufacturing and assembly efficiencies. In the interest of brevity, specific reference and explanation of components shared between head rail assembly  26  and rear frame rail assembly  32  will not be discussed. 
     With particular reference to FIG. 7, rear-latching mechanism  152  includes support bracket  102 ′ being coupled to support bracket  38  via conventional means, such as fasteners. Rear rail member  92 ′ receives attachment member  94  coupled to fabric cover  22  within receiving channel  96  formed in rear rail member  92 ′ to define the rear edge of coverage of roll up tonneau system  12 . Rear latching mechanism  152  still further includes a latching pawl  154 . Latching pawl  154  is generally L-shaped having a latching hook  156 , a trigger/ejector head  158 , and a centrally located pivot  160 . Latching hook  156  is shaped to selectively engage a flange  162  extending within C-shaped lower channel  116 . Latching hook  156  extends through an aperture  164  formed in second horizontal portion  54  of support bracket  38 . Aperture  164  is equidistant from an end of support bracket  38  compared to aperture  150  to permit support bracket  38  to be used on either a left or right side of cargo box  13 . Trigger/ejector head  158  is positioned near a rear end of rear rail member  92 ′ to permit easy actuation by a user. Trigger/ejector head  158  includes a protrusion  166 , which may extend through an aperture  168  to engage and translate rear rail member  92 ′ upward to signal to a user that rear rail member  92 ′ has been sufficiently unlatched. It should be understood that the length of trigger/ejector head  158  from pivot  160  may be increased relative to the length of latching hook  156  from pivot  160  for increase mechanical advantage. Rear latching mechanism  152  further includes a spring  170  biasing latching hook  156  in an engaged and locked position. 
     As seen in FIGS. 7-9, as trigger/ejector head  158  is depressed in a counter-clockwise direction, trigger/ejector head  158  pivots upward about pivot  160 . Such rotation disengages latching hook  156  from flange  162 . Continued depression of trigger/ejector head  158  causes trigger/ejector head  158  to engage an underside of rear rail member  92 ′, thereby pivoting rear rail member  92 ′ about curved portion  98 . Rear rail member  92 ′ may then be removed from support bracket  102 ′. 
     Receiving channel  97  formed in rearward rail member  92 ′ receives a bulbous seal  161  that has a first portion  163  slidable disposed in receiving channel  97 , a second D-shaped portion  165  coupled to first portion  163 , and an upwardly inclined wiper seal  167  that engages the side of tail gate  20  to provide a sealing engagement therebetween. Upwardly inclined wiper seal  167  and second portion  165  cooperate to form a channel  169  to collect and direct water outwardly. 
     Following disengagement of rear latching mechanism  152 , rear rail member  92 ′ may be rolled forward to gather fabric cover  22  at a forward location. To this end, it should be appreciated that the generally horizontally disposed hook-and-loop fastener system  49 , unlike prior art configurations, provides a simple “peel-off/on” arrangement in a direction perpendicular to the attachment plane of hook-and-loop fastener system  49 . Prior art systems often require additional layers of vinyl to separate the VELCRO® strips prior to attachment. Additionally, other prior art systems require a shearing action in order to disengage the VELCRO® strips. These systems require additional complexity to attach and additional force to separate and further limit the life of the VELCRO® strips. The “peel-off/on” arrangement of the present invention in a direction of perpendicular to the attachment plane provides improved simplicity in engagement and disengagement of hook-and-loop fastener system  49  and further improves the useful life thereof. This gentle action further permits the present invention to use aggressive hook-and-loop fastener systems that do not require them to be pushed into place; however, they are loaded in shear by fabric cover  22  yet may be released with a gentle peeling action. It should be appreciated that hook-and-loop fastener system  49  of the present invention is disengaged by a simple rolling of fabric cover  22  to its forward position. 
     The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.