Vehicle bed and cross rail attachment

A bed arrangement for a vehicle including a horizontally large floor member defined by a thin metal sheet having a plurality of raised stiffening ribs extending lengthwise thereof. The floor member has a cantilevered edge flange extending along a lengthwise side edge thereof, which edge flange protrudes downwardly below a bottom surface of the floor member. A hat-shaped cross rail is disposed transversely under said floor member, and has a pair of top flanges which supportingly engages the bottom surface of the floor member. The cross rail, where it crosses the edge flange, has a depression formed therein to provide clearance for the edge flange. The top flanges having flange sections which are deformed downwardly to define the profile of the depression while maintaining the continuity of the top flanges as they extend lengthwise of the cross rail.

FIELD OF THE INVENTION

This invention relates to a bed construction for a vehicle, particularly a pickup truck, and more specifically to an improved floor and cross rail constructional arrangement.

BACKGROUND OF THE INVENTION

The bed assembly of pickup trucks typically include a horizontally large floor, the lengthwise extending side edges being joined to upright inner side walls, and the transverse front edge being joined to an upright front wall. The horizontally large floor is normally constructed from multiple pieces or panels, including a main or center floor panel extending the full length of the bed and having a width which is generally slightly less than the width between the wheel well openings. The floor also includes side floor panels which extend sidewardly between the center floor panel and the adjacent inner side walls. The side floor panels typically have wheel well openings formed therein, and wheel well housings close the openings and are secured to the side floor panels and the adjacent upright inner side walls.

In a conventional bed assembly, similar to that summarized above, the floor panels are conventionally stamped or pressed from thin metal sheet so as to provide the floor panels with a plurality of generally parallel ribs which extend lengthwise of the bed to provide appropriate strength and stiffening. In recent years, many of the floor panels, particularly at least the center floor panel, are roll-formed to provide improved performance characteristics both with respect to strength and economy.

In the construction of a bed assembly employing a floor defined by multiple floor panels, as summarized above, it is conventional to provide the lengthwise extending edges of the floor panels, where such edges abut, such as where the outer longitudinal side edges of the center panel abut the respective inner longitudinal side edges of the side floor panel, with downward flanges which preferably extend lengthwise of the floor panel. These flanges are positioned to substantially abut one another during assembly of the floor and are fixedly joined, such as by welding. These edge flanges, due to their being turned downwardly relative to the horizontal orientation of the floor panel, provide significantly increased strength and rigidity to the floor. However, these downward flanges create significant interference problems at locations where they cross the underlying cross rails. For example, in constructions where the flanges protrude downwardly from the base or lower level of the ribbed floor panel, the flanges must be notched throughout the height thereof at locations corresponding to the cross rails so as to eliminate interference. This severe notching of the flanges, however, creates an obvious and undesirable weakness in the floor at this area, and in addition requires additional manufacturing operations and manipulations.

To improve on the undesired weakening created by notching the downward flanges associated with the base level of the floor, another construction has been developed wherein the edge flanges on the floor panels are formed so as to protrude downwardly from the top wall level associated with the floor panel ribs. That is, the floor panels are formed so that the longitudinal edges define partial upwardly-protruding ribs, and the edge flange then protrudes downwardly from the top wall of this edge rib. The edge flange, however, typically has a width (i.e. height) which is greater than the height of the ribs formed in the floor panel, so that the edge flange still requires that a portion of the height thereof be removed or recessed to provide appropriate clearance for the cross rails when the floor is fixedly seated thereon. This construction does provide at least some partial edge flange extending along the entire length of the floor panel and provides improved strength and rigidity. This latter construction, however, results in the seam, namely the line created where the longitudinally adjacent edge flanges abut, being disposed in a raised rib, rather than in a valley between adjacent ribs, and it has been suggested that this causes the seam to be more visible and less aesthetically desirable when incorporated into the finished vehicle bed assembly.

In a continuing effort to improve on the above construction, particularly as it relates to the fixed joining of longitudinal edges between sidewardly adjacent floor panels, it has also been suggested to provide a small notch transversely across the top of the cross rail so as to accommodate therein the edge flanges of the floor panels. While such notch does provide improved characteristics with respect to the construction of the floor panels and hence makes it unnecessary to notch or recess the edge flanges, nevertheless the presence of the notch in the cross rail provides a reduction in the strength and integrity of the cross rail.

In a known construction of the type employing a notch or depression in the cross rail, the cross rail is suitably shaped so that the notch or depression opens downwardly from the upper surface thereof at a location below the edge flanges of the floor panels, with the forming of the notch or depression also causing a downward deformation of the top flanges on the cross rail. With this known construction, however, while this does provide improved clearance for the edge flanges of the floor panels, nevertheless the depression also reduces the available contact between the floor panels and the top flanges of the cross rail with respect to permitting proper spot welding therebetween. This known construction hence typically only permits spot welding in close proximity to the edge flanges along one side thereof between the cross rail and one of the floor panels. On the other floor panel, however, there is insufficient contact between the base of the floor panel and the top flange of the cross rail to permit spot welding in close proximity to the edge flanges, and hence the spot weld is typically provided a substantial transverse distance from the edge flange, namely on the other side of the adjacent upstanding rib which is closest to the edge flange. The spot welds associated with the adjacent floor panels, which spot welds attempt to sidewardly straddle the seam defined by the adjacent edge flanges, are hence widely spaced apart and this impacts the strength and integrity of the joint.

Accordingly, it is an object of this invention to provide an improved bed construction for a vehicle, such as a pickup truck, which construction addresses the problems summarized above and provides an improved constructional relationship between the floor, as defined by a plurality of floor panels, and its fixed association with and support by a plurality of underlying cross rails.

More specifically, the present invention relates to an improved bed assembly for a pickup truck having a horizontally large bed or floor defined by a plurality of separate floor panels, preferably a main center floor panel which extends sidewardly between and joins to right and left side floor panels, the latter defining therein right and left wheel well openings respectively. The floor panels are supported on and fixedly secured to a plurality of cross rails which extend transversely under the floor, which cross rails conventionally have an upwardly-opening hat-shaped cross section. At least the main center floor panel is preferably provided with a plurality of upwardly-protruding reinforcing ribs extending lengthwise of the panel, with the ribs being disposed in generally parallel but sidewardly spaced relationship. The opposite longitudinally-extending side edges of the center floor panel are defined by the base wall of the center panel, that is, the floor elevation which corresponds to the valley between adjacent ribs, and are additionally provided with a downwardly-cantilevered edge flange formed so as to extend substantially continuously lengthwise therealong. The edge flange typically has a width (i.e. height) which is greater than the height of the ribs relative to the base wall. Similar such edge flanges are formed on and extend lengthwise along the inner longitudinal side edges of the right and left floor panels, whereby the opposed edge flanges abut and are secured together, such as by a plurality of spot welds, to rigidly join the floor panels together. When joined together, the seam defined at the abutting side edges of the floor panels is disposed at the base of the floor, rather than in the top of a rib. To accommodate the significant downward protrusion of the adjacent abutting edge flanges, each cross rail at a location corresponding to the edge flanges is provided with a smoothly configured depression formed downwardly from the upper surface thereof. The depressions are formed in the cross rails by deforming the upper portion of the cross rail, while not effecting any significant material removal, whereby the top flanges of the hat-shaped cross rail extend continuously throughout the length of the cross rail and, at the region of the depression, are smoothly and gradually deformed downwardly and then upwardly in a continuous and smooth manner so as to create the depression while at the same time maintaining the continuous lengthwise-extension of the top flanges while maintaining them free of abrupt corners or directional changes. The hat-shaped cross section of the cross rail is hence maintained at all locations throughout the length thereof, even in the region of the depression, whereby the depression readily accommodates the downwardly protruding abutting edge flanges on the floor panels while at the same time the cross rail maintains a high level of strength and structural integrity. The depressions in the cross rails can be formed by reshaping of the cross rail in a suitable stamping or forming die. Alternatively, roll forming of the cross rails is preferred, and use of a variable roll forming process can be adopted to permit forming of the depressions in the cross rails during the roll forming thereof.

In the improved construction, as aforesaid, the down-turned abutting edge flanges, where they transversely intersect the cross rails, can be provided with a shallow recess opening upwardly from the lower free edge of the respective edge flange to provide sufficient clearance between the edge flange and cross rail, thereby minimizing the required depth of the depression, which in turn minimizes the extent of the depression in the lengthwise direction of the cross rail. The recess preferably has a depth which is less than one-half the height of the edge flange to maintain the lengthwise continuity of the edge flange along the floor panel, and hence maintain desired strength and rigidity lengthwise along this edge.

In the improved bed construction of the present invention, as aforesaid, the center floor panel is preferably provided with depressions formed at select locations in the raised ribs so as to facilitate securement of the center floor panel to the cross rails, such as by spot welding. More specifically, the outermost rib located adjacent each longitudinal side edge of the center floor panel, at locations corresponding to the cross rails, is preferably deformed downwardly to create a deformed region which opens inwardly from the base floor adjacent the longitudinal side edge and which is substantially coplanar therewith. This depression enables the depressed wall to engage upper surfaces of the cross rail top flanges directly adjacent one end of the depression so as to permit spot welding to the top flanges. This provides desired strength and rigidity with respect to connection of the center floor panel to the cross rails, while at the same time enabling the depressions to extend lengthwise of the cross rail through a sufficient extent to permit a gradual change in curvature of the cross rail top flanges throughout the length of the depression, thereby minimizing the effect of the depression on the structural characteristics of the cross rail.

Other objects and purposes of the present invention will be apparent to persons familiar with constructions of this type upon reading the following specification and inspecting the accompanying drawings.

Certain terminology will be used in the following description for convenience in reference only, and will not be limiting. For example, the words “upwardly”, “downwardly”, “rightwardly” and “leftwardly” will refer to directions in the drawings to which reference is made. The word “front” as used in association with the floor or bed assembly will be used to designate that end which is closest to the front of the vehicle. The words “inwardly” and “outwardly” will refer to directions toward and away from, respectively, the geometric center of the bed assembly and designated parts thereof. Said terminology will include the words specifically mentioned, derivatives thereof, and words of similar import.

DETAILED DESCRIPTION

FIG. 1is a fragmentary illustration of parts of a vehicle bed assembly10, such as for a pickup truck. The bed assembly10includes a large and substantially horizontally extending floor or bed11intended for supporting loads thereon. This floor or bed11is, in a conventional manner, supported on a plurality of generally parallel and sidewardly spaced cross or frame rails12which extend transversely beneath the floor, only two such rails being diagrammatically illustrated inFIG. 1. The bed assembly includes right and left inner side walls13and14, respectively, which are fixedly interconnected to and protrude substantially perpendicularly upwardly from the floor11adjacent opposite longitudinally extending side edges thereof. The inner side walls13–14in turn, at front edges thereof, are rigidly joined to a front wall or panel15which is fixed to and protrudes substantially perpendicularly upwardly from the front edge of the floor11. The rear edge16of the floor11is conventionally supported on a rear cross rail (not shown), and the rear cross rail in conjunction with upright rear posts (not shown) define a rear access opening for the bed assembly, which access opening is conventionally closed by a swingable tailgate (not shown).

The bed assembly10also typically includes right and left wheel well housings, only the left housing17being illustrated inFIG. 1. Such housings are fixedly secured around the edges of wheel clearance openings formed in the floor and the side walls as is conventional.

The floor11as associated with the present invention, and as is conventional, is formed from a plurality of separate preformed floor panels which fixedly cooperate to define the overall floor11. In the floor associated with the bed construction of this invention, the floor11includes a main or center floor panel21which extends longitudinally throughout substantially the full length of the bed assembly. This center floor panel21preferably has a width which is normally slightly less than the transverse spacing between the opposed wheel well housings17, whereby the center bed panel22in plan view hence has a substantially rectangular configuration.

The floor11also includes right and left side floor panels22and23, respectively, which effectively extend sidewardly between the respective adjacent side edge of the center floor panel21and the respective adjacent inner side wall13or14. The right and left side floor panels22and23have wheel well openings formed therein, the latter being enclosed by the respective wheel well housing17.

The center floor panel21is preferably an integral and monolithic one-piece construction formed from thin metal (i.e. steel) sheet. The center floor panel21is provided with a plurality of reinforcing ribs25which are deformed upwardly from a planar base wall24, with the ribs25preferably extending substantially throughout the lengthwise extent of the center floor panel. The reinforcing ribs25preferably have a shallow channel-shaped cross section which opens downwardly, with the individual rib being defined by a top wall26which is spaced upwardly a small distance above the base wall24and which is interconnected to the base wall by downwardly sloped side walls27. A plurality of such ribs25are formed in generally parallel but sidewardly spaced relationship so that the ribs extend generally parallel to the longitudinally extending centerline28of the center floor panel. The ribs are preferably substantially uniformly sidewardly spaced apart and define valleys or depressions29between each sidewardly adjacent pair of ribs, the bottom wall of each valley being defined by the planar base wall24.

The center floor panel21has opposite sides thereof defined by longitudinally-extending and parallel side edges31. Each side edge31defines a downwardly turned edge flange33which is cantilevered downwardly and extends substantially continuously along the full lengthwise extent of the side edge, and which terminates in a lower free edge37. The flange33protrudes downwardly in generally perpendicular relationship to the plane of the base wall24, and this flange33at its upper end is joined to the base wall24through a rather sharp corner or bend. The base wall24, adjacent the longitudinally extending side edge31, defines a base wall section32which is coplanar with the base wall24and, throughout the longitudinal extent of the center floor panel, extends transversely between the downturned flange33and the adjacent reinforcing rib (that is, the reinforcing rib25positioned most closely adjacent the side edge of the center floor panel). The transverse width of this base wall section32is, as shown byFIG. 2, significantly less than the width of the base wall24associated with the valleys29defined between adjacent ribs25.

As illustrated byFIGS. 2,3and3A, each of the side floor panels, such as the right side panel22illustrated inFIGS. 2 and 3, has a down-turned edge flange34associated with and extending lengthwise along the inner longitudinally-extending side edge thereof. The edge flange34is monolithically and integrally joined to the respective side floor panel22,23and is cantilevered downwardly in generally perpendicular relationship. The edge flange34has generally the same vertical depth and extends generally parallel to the opposed edge flange33associated with the center floor panel21. When the side floor panels22,23are positioned so as to effectively abut opposite sides of the center floor panel, the opposed edge flanges33and34effectively abut as illustrated inFIG. 3A, and are suitably fixedly joined, such as by a plurality of spot welds positioned at selected intervals longitudinally along the flanges. This joined flange arrangement hence provides effective rigid joining of the floor panels, and more significantly provides the assembled floor with significantly increased rigidity and structural integrity.

The side floor panel22,23can, as illustrated inFIGS. 2,3and3A, be provided with one or more raised reinforcing ribs35extending longitudinally therealong, which ribs will typically terminate at or short of the wheel well housing. If provided, the rib35is preferably spaced transversely from the edge flange34so as to define a flat base wall region38which is substantially coplanar with the adjacent base wall section32, which base wall sections32and38cooperate to define a valley36which is sized so as to be substantially the same or closely similar to the size of the valleys29defined between ribs25associated with the center floor panel21. As illustrated byFIGS. 3 and 3A, the width of the base wall section32as defined between the outermost raised rib25and the respectively adjacent edge flange33is substantially smaller (i.e. narrower) than the width of the flat base wall section38as associated with the adjacent side floor panel22, which flat base wall section38also extends transversely between the respective edge flange34and the adjacent raised reinforcing rib35. By making the base wall section38of substantially greater width than the base wall section32, while maintaining the width of the valley36as defined by the combined widths of these wall sections consistent with the width of the other valleys29, the wall section38hence extends sufficiently transversely so as to create contact with the top flanges43of the cross rail adjacent one end of the depression46, thereby permitting spot welding (as indicated at55inFIG. 3) between the base wall section38and the top flanges43, as described in greater detail hereinafter. The longitudinally-extending seam defined by the opposed abutting edge flanges33and34is associated with the bottom or base wall of this valley36, whereby the seam can be suitably caulked or otherwise filled, while at the same time being disposed in a position which is perceived to be less visually noticeable.

The cross rails12which project transversely under and structurally support the floor11typically and preferably have an inverted hat-shaped cross section which, as illustrated byFIG. 4, is defined by a generally upwardly-opening channel-shaped profile or body defined by spaced side walls41which project upwardly from a bottom wall42. The side walls41, which may and frequently do slightly diverge as they project upwardly, terminate in top flanges43which are bent relative to the side flanges41so as to project in a generally horizontal plane. In the illustrated and preferred construction, the pair of flanges43project sidewardly in opposite directions, and specifically individually project outwardly away from the respective side wall41. These top flanges43define thereon substantially horizontal and coplanar upper support surfaces44which provide direct supportive engagement with the underside of the floor11, and more specifically provide direct supportive engagement with the underside of the base plates associated with the different floor panels, such as the base wall24of the center floor panel21. The various floor panels21,22,23are fixedly secured to the cross frames12preferably by a plurality of spot welds which are created between the base walls of the floor panels, such as the base wall24of the center panel21, and the top flanges43of the respective cross rail12.

Each of the cross rails12, at a location where the cross rail intersects the opposed connected edge flanges33and34, is provided with a downwardly-formed recess or depression46(FIG. 2) formed in the upper portion of the cross rail12. This depression46is positioned so as to project downwardly from the horizontal plane defined by the upper surfaces44of the top flanges43, with the depression46projecting downwardly a significant extent into the upper portion of the side walls41so that the lowermost point of the recess is hence disposed at an elevation significantly below the normal horizontal elevation of the top flanges43. The depression46extends transversely across the entire width of the cross rail12and hence, in actuality, constitutes a pair of identical depressions which are transversely aligned, one such depression being formed downwardly in each of the side walls41and its associated top flange43.

While the depression46opens downwardly into the side walls43from the upper edge thereof and hence reduces the height of the side walls41in the region of the depression, this depression nevertheless does not result in any severing or removal of the top flanges43. Rather, the formation of the depression is such that the top flanges43, in the region of the depression, are deformed downwardly to define deformed flange sections47(FIG. 2) which correspond to the shape of the depression and which extend continuously along the periphery of the depression, with opposite ends of the deformed flange sections47being monolithically and integrally joined and smoothly merged into the horizontal top flanges43at opposite lengthwise-ends of the depression.

The depression46preferably has a configuration, as defined by its edge or outer profile, which is smoothly curved throughout the extent thereof so as to eliminate or at least greatly minimize any sharp bends or severe curvature changes. In this regard, the depression46and the deformed flange sections47which extend along the edge thereof are defined generally by a smoothly curved, upwardly-opening, concave curvature which, at opposite ends, namely where it joins to the horizontal top flanges43, is reversely smoothly bent or curved so as to effect a smooth and continuous transition into the horizontal top flanges43.

The curvature or shape of the depression46and deformed flange sections47will typically and preferably resemble an upwardly-opening arc which, at opposite ends, is reversely curved or bent so as to transition into the horizontal top flanges43. The depression46, as it extends in the lengthwise direction of the cross rail12, will have a length which is substantially greater than its depth, which depth will be maintained at a minimum so as to provide solely the clearance necessary to accommodate the edge flanges33,34, whereby the bottom or lowest elevation of the depression will typically be at an elevation which is substantially above the elevational midpoint of the side walls41.

To minimize the depth and lengthwise extent of the depression46as formed in the cross rail, the depression46may and preferably is formed with a depth which is less than the depth (i.e. height) of the edge flanges33and34. To provide clearance between the cross rail and edge flanges, the edge flanges are preferably provided with a shallow recess39(FIGS. 5,8and9) opening upwardly from the lower free edge37thereof. This recess39opens upwardly from the lower edge37through a height which is preferably significantly less than the overall height of the flange33,34, with the height of the recess39preferably being less than one-half of the overall height of the flange33,34. Recess39also extends lengthwise along the respective flange33,34through only a lengthwise extent sufficient to provide clearance at the location where the flanges and cross rail transversely intersect, with the flanges otherwise being of full height. The recess39, at opposite lengthwise ends thereof, is joined to the lower free edge37through appropriate rounded end walls so as to avoid any abrupt or sharp corners.

With the construction described above, the edge flanges hence maintain their continuity lengthwise along the edges of the floor panels, and provide added strength and rigidity along the floor panel edges, even at locations where the floor panels cross the cross rails. At the same time, however, the edge flanges can be associated with and project downwardly from the base wall of the floor panel, and the depressions as formed in the cross rails are shaped and formed so as to minimize any reduction in strength and/or minimize any significant stress-raising configurations. By combining a shallower depression with an associated shallow recess in the edge flange, this tends to optimize the cooperation between the depression and edge flange by maintaining the continuity of the edge flange along the floor panel, while at the same time minimizing not only the depth of the depression but also the length of the depression in the lengthwise direction of the cross rail. This latter feature hence minimizes the length of disruption in the horizontal top flanges on the cross rail, and in cooperation with the depressions or flattened regions formed in at least one of the adjacent raised reinforcing ribs, enables the floor panels to be spot welded to these horizontal top flanges at locations positioned more closely adjacent the lengthwise free edges of the floor panels, thereby providing improved manufacturing capability and resulting strength and rigidity.

As exemplary of the preferred construction as described above, the edge flange33,34may typically have a height in the neighborhood of 16 to 17 mm, which edge flange height is typically greater than the height of the channel-shaped ribs25formed in the floor panel. The depression46, on the other hand, will preferably have a depth, as measured downwardly from the horizontal plane defined by the top surfaces44, in the range of from about 10 mm to about 15 mm. Creation of the recess39opening upwardly from the lower free edge37of the edge flanges, hence enables the edge flanges to retain at least half of their height, and preferably more than half of the height, while at the same time maintaining a minimum of about 3 mm clearance between the recessed edge flange and the deformed flange sections47defining the depression46.

To provide for proper and fixed securement, such as spot welding, of the floor panel members21–23to the top flanges43of the cross rails12in close proximity to the seams defined by the abutting edge flanges33–34, one of the adjacent raised ribs as provided on either the center floor panel21or the respective side floor panel22–23is preferably provided with flats or depressions therein so as to facilitate spot welding of the floor panels to the top flanges43directly adjacent opposite longitudinal ends of the depressions46.

In the illustrated and preferred embodiment, as shown inFIGS. 3,3A,6,8and9, the outermost rib25associated with the center panel21, namely the rib25′ positioned most closely adjacent the seam defined by the flanges33,34, is provided with a depression or recess51therein at a location corresponding to each cross rail. In the center panel illustrated inFIG. 6there is provision for four cross rails as evidenced by the four spaced depressions51formed in the lengthwise extent of each sidemost rib25′. These depressions51are not shown inFIG. 1for simplicity of illustration.

As shown in greater detail inFIGS. 3,3A,8and9, the depression51as formed in the sidemost rib25′ is located directly over the cross rail12, with the depression51extending lengthwise of the rib by a distance slightly greater than the transverse width of the cross rail12. The depression51opens inwardly into the rib from the outermost side thereof (i.e., the side which joins to the base wall section32associated with the edge flange33). This depression51in the illustrated and preferred embodiment does not project transversely through the entire width of the rib25′, but rather is defined by a concavity which is depressed downwardly from the rib top wall26and inwardly from the outer side wall27so that the depression is bounded by a side wall53which is of a generally arcuate or channel shaped configuration and which merges with the outer rib side wall27. The depression51is formed by a suitable deforming operation, such as in a stamping press, which deforms the rib25′ downwardly so that the bottom wall52of the depression functions substantially as an inward coplanar extension of the base wall section32. This base wall52, when viewed from above as illustrated inFIG. 3, is sized so that it projects transversely inwardly to an extent beyond the inner lengthwise extent of the depressions46formed in the underlying cross rail12. This enables the rearward or innermost portion of the base wall52to directly overlie the horizontal top surface44on the top flanges43just inwardly of the depression46, thereby facilitating creation of spot welds, as indicated at54, between the base wall52and the horizontal top flanges43of the cross rail.

Other spot welds55are also preferably provided between the base wall38associated with the adjacent side floor panel22and the flat top flanges43of the cross rail at a location closely adjacent the other longitudinal end of the depression46. These spot welds54and55are hence positioned closely adjacent opposite longitudinal ends of the depression46, and permit fixed and hence rigid securement of the adjacent floor panels to the cross rails in close proximity to and on opposite sides of the longitudinally extending seam defined by the abutting edge flanges33–34. At the same time, however, since the depressions51formed in the edgemost rib25′ do not transversely penetrate across the entire width of the rib, this edgemost rib still maintains a continuous channel-shaped reinforcing configuration throughout the entire length of the center floor panel21so as to prevent any significant decrease with respect to the rigidity and structural integrity thereof. The above construction hence provides significantly improved joint integrity by minimizing the size and disruption created by forming of the depression in the cross rail, by minimizing any relief or recess which is formed in the abutting edge flanges where they transversely extend across the edge rail, by permitting direct spot welding of the base wall of the sidewardly adjacent floor panel members directly to the underlying top flanges of the cross rail in very close proximity to and on directly opposite sides of the abutting edge flanges, while maintaining the seam defined by the abutting edge flanges in the bottom of a valley which has the same general size or width as the other valleys associated with the floor so as to provide uniformity of appearance.

In the improved bed arrangement of the present invention, as illustrated and described herein, the cross rails12can be formed in any conventional manner, either by stamping or roll forming, and the depressions46thereafter formed therein, such as by a deforming die or a suitable stamping press. Such process preferably effects reshaping of the cross rail so as to effect forming of the depression46therein, without effecting any significant removal of material, while maintaining the continuous and monolithic top flanges lengthwise along the cross rail including the reshaping of these flanges so that they extend around the periphery of the depression as formed in the upstanding side walls41. Further, if the cross rails are roll-formed, which is a preferred construction inasmuch as such is believed to permit the cross rails to be of more uniform and accurate cross section while permitting roll forming from higher strength steel, then the roll forming of the cross rails is believed to permit more economical and improved forming of the depressions46therein since, by using a variable roll forming device, the depressions can be formed in the cross rail as the cross rail is being formed during its movement through a multiple-stage roll forming mill.

While the above description and related drawings relate primarily to the seam connection between the adjacent side flanges on the panels21and22, it will be understood that the same seam connection also exists between the adjacent side flanges on the panels21and23.

While the side floor panels may be defined by separate panel members formed by roll forming or stamping, it will be appreciated that other constructions can be used. For example, the side floor panel may be part of a one-piece stamping which also includes the adjacent inner side wall and the wheel well housing. In a preferred construction, the side floor panel and the adjacent inner side wall are defined by a monolithic one-piece roll-formed member as disclosed in copending Ser. No. 11/105 330.