Abstract:
A roll formed step rail for a vehicle comprises an elongated rail body having two opposing edges which define a longitudinal channel. The channel receives a pinch clamp which is wider than the channel and has a fastening hole and an alignment means. The rail body is lowered onto the mounting surface of a mounting bracket adapted for rigid connection to a vehicle. The mounting surface defines another fastening hole and another portion of the alignment means. A fastener draws the pinch clamp and the mounting surface toward opposite sides of the opposing edges of the rail body. Because the pinch clamp spans the width of the channel and is aligned properly relative to the mounting surface, the rail body is secured between the clamp and the mounting surface by the tightened fastener.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 12/107,472, filed Apr. 22, 2008 now U.S. Pat. No. 7,946,604, entitled ROLL FORMED STEP RAIL FOR A VEHICLE, which was a Continuation of U.S. patent application Ser. No. 11/304,493, filed on Dec. 14, 2005 (now U.S. Pat. No. 7,360,779, issued Apr. 22, 2008) entitled ROLL FORMED STEP RAIL FOR A VEHICLE, which claimed the benefit of priority from U.S. Provisional Application No. 60/741,522 filed Dec. 1, 2005. 
    
    
     TECHNICAL FIELD OF THE INVENTION 
     This invention is related to automotive vehicle body/chassis accessories such as running boards, side bars and tube steps, and more particularly, to step rails manufactured using a roll forming process for mounting on the sides of vehicles such as pickup trucks and sport utility vehicles. 
     BACKGROUND OF THE INVENTION 
     It is well known to mount body/chassis accessories such as running boards, side bars or tube steps (referred to collectively herein as “step rails”) below the side doors of automotive vehicles such as pickup trucks and sport utility vehicles (SUVs) to provide a convenient step for use when entering/exiting the vehicle and for protection of the vehicle against side body damage. In addition, these step rails frequently serve as styling members intended to personalize or enhance the appearance of the vehicle. As such, both the mechanical strength properties and the external appearance properties of step rails are important. Further, since step rails are exposed to the rain, ice, mud, road chemicals (e.g., salt) and other harsh environmental materials, it is desirable that they be resistant to corrosion and/or surface finish degradation. 
     Conventional step rails are typically formed by bending tubular metal stock (e.g., where a tubular cross section is desired), by stamping flat metal blanks (e.g., where irregular, concave and/or convex surface features are desired), or by metal extrusion (e.g., where a constant cross section is desired). Commonly used materials for bending and stamping include steels, stainless steels and aluminum alloys, whereas extrusion in typically restricted to aluminum alloys. Ordinary steel step rails are typically painted, chrome plated, or powder coated to provide corrosion resistance and an attractive appearance. Stainless steel and aluminum alloy step rails may be left bare since those materials are inherently corrosion resistant, however, they are often polished to produce a reflective (i.e., “mirror”) finish or brushed to produce a matte (i.e., “brushed”) finish. Less frequently, they may also be painted or powder coated. 
     It will be appreciated that it is typically much easier (an hence, less expensive) to produce a high quality, uniform surface finish on basic metal stock (e.g., straight tubes, flat sheets, etc.) than it is on complex shapes such as a formed step rail. This is especially true in the case of bare metal finishes such as mirror and brushed finishes. Thus, it is desirable that the surface finish be applied to the basic metal stock before forming. However, the bending, stamping and extrusion processes conventionally used in forming step rails tend to mar, distort or otherwise damage the surface finish during forming. For low quality parts, such damage may be acceptable, given the savings in manufacturing costs. But for top-quality parts, even minor surface finish imperfections may cause the part to be rejected. Thus, the cost savings achieved by pre-finishing the stock may be lost due to a high defect rate in he finished product. A need therefore exists for a high quality formed step rail made from pre-finished stock using a process that will preserve the original high quality surface of the stock in the finished product. 
     It will also be appreciated that step rails must be strong enough to support the loads imposed upon them (e.g., the weight of passengers on the step) without failing, and be stiff enough to avoid undue deflection (“flexing”) and/or vibration during use. At the same time, it is desirable to minimize the overall weight and amount of material used in the step rail for performance and cost reasons. A need therefore exists for a formed step rail having a structural configuration that is relatively efficient, i.e., producing high strength and stiffness for the amount of material used. 
     After fabrication, the step rails must be mounted on the vehicle. This is typically accomplished through the use of bracket systems designed for the particular step rail/vehicle combination. However, ordinary variation in the location of the mounting holes provided on the vehicle by its manufacturer can sometimes make it difficult to install and adjust the step rails without requiring “field modification” of the bracket system and/or step rail itself. Such modifications are undesirable as they introduce additional complexity (and hence, additional cost) to the step rail mounting. Further, if done improperly, such modifications may also affect the structural integrity of the step rail. A need therefore exists for a bracket system which provides for uncomplicated installation and adjustment of the step rails even in the face of normal variation in vehicles. 
     While necessary for mounting the step rail to the vehicle, the bracket system is typically not considered a styling member. A need therefore exists for a step rail/bracket system combination which conceals as much of the bracket system as possible when viewed from normal viewing angles. 
     SUMMARY OF THE INVENTION 
     The present invention disclosed and claimed herein comprises, in one aspect thereof, a roll formed step rail for a vehicle including an elongated rail body having a continuous rail wall of substantially uniform thickness. The rail wall describes a continuous cross-sectional profile between two elongated free edges, the cross-sectional profile of the rail being substantially uniform along the length of the rail body. The cross-sectional profile of the rail body includes a relatively flat top portion disposed between a substantially semi-circular front curved portion and a substantially quarter-circular rear curved portion. A rear mounting lip extends forward from the rear curved portion to one of the elongated free edges. A front mounting lip extends upward and then rearwards from the front curved portion to another of the elongated free edges. The elongated free edges are generally in line with one another, but spaced apart to define a longitudinal channel therebetween having a predetermined width. The rail body is formed from a sheet of material by a process of roll forming. 
     The present invention disclosed and claimed herein comprises, in another aspect thereof, a step rail assembly for a vehicle. The assembly includes an elongated rail body having two opposing edges defining a longitudinal channel. At least one mounting bracket is provided having a first and a second end connected by a bracket arm. The first end is adapted for a rigid connection to a mounting point of the vehicle. The second end has a generally upwardly-facing, generally flat mounting surface defining a first fastening hole and a first portion of an alignment device. A pinch clamp is provided having a major dimension and a minor dimension disposed on generally perpendicular axes. The pinch clamp defines a second fastening hole and a second portion of the alignment mechanism. The major dimension is greater than a width of the longitudinal channel, and the minor dimension is less than the width of the longitudinal channel. The second portion of the alignment device is adapted to selectively engage the first portion and thereby prevent relative rotation between the mounting bracket and the pinch clamp when the minor dimension of the pinch clamp is substantially aligned with the longitudinal channel. The rail body can be rigidly connected to the mounting bracket by first loosely inserting a fastener through the respective fastening holes in the mounting surface and the pinch clamp to rotatably attach the pinch clamp to the mounting bracket, then turning the pinch clamp to align the major axis with the longitudinal channel, then lowering the rail body toward the mounting bracket such that the pinch clamp passes between the opposing edges of the rail body and the opposing edges come into contact with the mounting surface, then rotating the pinch clamp to align the major axis perpendicular to the longitudinal channel such that the clamp overlies the opposing edges of the rail body and the first portion of the alignment device engages the second portion, and then tightening the fastener to pull the pinch clamp and flat face portion of the bracket arm tightly against opposite sides of the opposing edges of the rail body. 
     The present invention disclosed and claimed herein comprises, in a further aspect thereof, a method of forming a step rail of predetermined length for a vehicle. A quantity of flat-rolled metal is provided having an overall length and a substantially finished surface on at least one side. The substantially finished surface has a layer of protective plastic film adhering thereto. The flat-rolled metal is prepared for roll forming while retaining the layer of protective plastic in place on the substantially finished surface. The flat-rolled metal is roll formed into a rail body of essentially constant cross section by feeding the metal between successive pairs of rolls that increasingly shape it until the desired cross section is completed. The cross section of the rail body has a non-linear, open contour in which the two ends of the shape are not brought together and the rail body has the substantially finished surface facing outward. The roll formed rail body is then trimmed to the predetermined length and the layer of protective plastic film is removed from the substantially finished surface. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying Drawings in which: 
         FIG. 1  is a perspective view of a step rail in accordance with one embodiment of the invention, mounted on a SUV (shown in phantom); 
         FIG. 2  is an enlarged perspective view of the step rail of  FIG. 1  and portions of the bracket system; 
         FIG. 3  is a cross-sectional view of the step rail taken along line  3 - 3  of  FIG. 2 ; 
         FIG. 4A  is an exploded perspective view of the unassembled step rail and bracket system in accordance with another embodiment; 
         FIG. 4B  is a perspective view of the assembled step rail and bracket system of  FIG. 4   a;    
         FIG. 5  is a perspective view of the pinch clamp of the step rail and bracket system; 
         FIG. 6  is a side elevation view of the bracket arm of the step rail and bracket system; 
         FIG. 7  is a is a perspective view of a side step rail for a vehicle showing another embodiment of the invention; 
         FIG. 8  is cross-sectional view thereof taken along line  8 - 8  of  FIG. 7 ; 
         FIG. 9  is cross-sectional view thereof taken along line  9 - 9  of  FIG. 7 ; 
         FIG. 10  is a front elevation view thereof; 
         FIG. 11  is a right end view thereof; 
         FIG. 12  is a left end view thereof; 
         FIG. 13  is a rear elevation view thereof; 
         FIG. 14  is a top plan view thereof; 
         FIG. 15  is a bottom plan view thereof; 
         FIG. 16  is a is a perspective view of a side step rail for a vehicle showing another embodiment of the invention, the cross-sectional, elevation and plan views thereof being substantially similar to those of  FIG. 7 ; 
         FIG. 17  is a is a perspective view of a side step rail for a vehicle showing yet another embodiment, the cross-sectional, elevation and plan views thereof being substantially similar to those of  FIG. 7 ; 
         FIG. 18  is a is a perspective view of a step rail for a vehicle showing as still further embodiment; 
         FIG. 19  is a front elevation view thereof; 
         FIG. 20  is a right end view thereof; 
         FIG. 21  is a left end view thereof; 
         FIG. 22  is a rear elevation view thereof; 
         FIG. 23  is a top plan view thereof; 
         FIG. 24  is a bottom plan view thereof; 
         FIG. 25  is an enlarged cross-sectional view thereof taken along line  25 - 25  of  FIG. 18 , and further is an enlarged cross-sectional view of the embodiment of  FIG. 26  taken along line  25 - 25  of  FIG. 26 ; 
         FIG. 26  is a is a perspective view of a step rail for a vehicle showing another embodiment; 
         FIG. 27  is a front elevation view thereof; 
         FIG. 28  is a right end view thereof; 
         FIG. 29  is a left end view thereof; 
         FIG. 30  is a rear elevation view thereof; 
         FIG. 31  is a top plan view thereof; 
         FIG. 32  is a bottom plan view thereof; 
         FIG. 33  is a series of sequential end views during the roll forming operation showing successive profiles of the rail body from view A (first profile) to view Q (final profile); 
         FIG. 34  is an overlaid series of sequential end views of the roll forming operation of  FIG. 33  showing the successive profiles of the rail body from view A (first profile) to view Q (final profile) as viewed from a fixed perspective; 
         FIG. 35  is a cross-sectional side view of the rail body showing minimum surface finish requirement regions in accordance with another embodiment; and 
         FIG. 36  is a block diagram showing a method of assembling a step rail to a mounting bracket system in accordance with yet another embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, wherein like reference numbers are used herein to designate like elements throughout the various views, embodiments of the present invention are illustrated and described, and other possible embodiments of the present invention are described. The figures are not necessarily drawn to scale, and in some instances the drawings have been exaggerated and/or simplified in places for illustrative purposes only. One of ordinary skill in the art will appreciate the many possible applications and variations of the present invention based on the following examples of possible embodiments of the present invention. 
     Referring now to  FIG. 1 , there is illustrated one embodiment of a roll formed step rail for a vehicle in accordance with the current invention. The step rail  100  includes a rail body  102  and end caps  104 . A bracket system  106  is used to attach the step rail  100  to the side of the vehicle  110  (shown in phantom). The bracket system  106  is normally not visible from a perspective view such as shown in  FIG. 1  but has been shown here for purposes of illustration. The specific location and appearance of the bracket system  106  relative to the rail body  102  is shown in greater detail herein. Additionally, while not shown in the embodiment of  FIG. 1 , step pads may also be attached to an upper surface of the step rail  100  as further described herein. 
     Referring now to  FIG. 2 , there is illustrated an enlarged view of the step rail  100 . The mounting brackets  106  include a bracket arm  112  having an upper bracket plate  114  adapted for attachment to a vehicle body. As stated with respect to  FIG. 1 , the bracket system  106  is not normally visible from a perspective view, but has been shown as visible in  FIG. 2  for purposes of illustration. In this embodiment, the upper bracket plate  114  includes an upper portion  116 , having a plurality of mounting holes  118  and a lower portion  120  that is angled with respect to the upper portion  116 . The lower portion  120  may be angled to provide a proper fit to a vehicle frame or sub-frame, to provide additional clearance for the rail body  102  or a user of the system, or for aesthetic reasons. 
     Referring now to  FIG. 3 , there is illustrated a cross sectional view of the rail body  102  taken through line  3 - 3  of  FIG. 2 . The rail body  102  has a relatively thin rail wall  302  that has been formed, preferably by roll forming, into a specialized curve profile as shown. The profile includes relatively flat top portion  304  disposed between a semi-circular front curved portion  306  and a quarter-circular rear curved portion  308 . A rear mounting lip  310  extends forward from the rear curved portion  308 . A front mounting lip  312  extends upward and then rearwards from the front curved portion  306 . The respective free ends  314  and  316  of the rear and front mounting lips  310  and  312  are generally in line with one another, but spaced apart to define a longitudinal mounting passage  318  having a predetermined width, denoted W c . 
     The rail body  102  is preferably formed of stainless steel material but may be formed of other steel alloys and/or aluminum alloys. The outer surfaces of the rail body  102  are preferably polished or finished to have a specific surface finish as further described herein. The rail body  104  profile is a preferably formed by the process of roll forming. It will be appreciated that roll forming involves passing flat rolled metal sheet stock through successive pairs of rolls that increasingly shape the originally flat stock into a desired cross section as shown. In a preferred embodiment of the invention, the flat rolled stock has a surface that is pre-finished and is rolled in such a manner that the original surface finish is not damaged by the rolling operation. Thus, after roll forming, the rail body  102  will require little, if any, additional surface finishing to achieve the final desired finish. In a more preferred embodiment, the original flat rolled metal stock has a layer of protective plastic film in place on the substantially finished surface. This protective plastic film remains in place during the roll forming operation. After the rail body  102  profile has been fully formed, the protective plastic may be removed. This protective plastic film helps maintain the substantially finished surface of the original stock in good condition during roll forming. 
     It will be appreciated that the flat rolled metal stock used for the roll forming operation may start out as coiled metal rolls or as flat sheets. Whether coiled rolls or flat sheets, the flat stock will be fed through the roll forming operation in a continuous manner and the rail bodies  102  may be trimmed to their final shape after the rolled form contour has been produced. After trimming to final shape, the end caps  104  and step pads (if used) may be added to the rail body. The end caps  104  and/or step pads will typically be formed of molded plastic, rubber, or resin, however they may be made of die-cast metal or other materials in some embodiments. 
     Referring now to  FIGS. 4A and 4B , there is illustrated enlarged views of the rail mounting bracket system in accordance with further embodiments of the invention. As seen in  FIG. 4A , the mounting bracket system includes the rail body  102 , bracket  106 , and a pinch clamp  402 . The bracket  106  includes an arm  112  having an upper plate  114  at the upper end and a lower plate  404  at the lower end as previously described. The lower plate  404  has a body  405  defining a fastener hole  406  and a first part  408  of an alignment device. In this case, the first part  408  of the alignment device comprises a pair of holes  410  formed in the body  405 . The pinch clamp  402  has a body  412  having a major dimension with a relatively large width, denoted W L , and a minor dimension with a relatively short width, denoted W s , that is shorter than W L . In the embodiment shown, the pinch clamp body  412  has a generally rectangular shape, but this is not required. Rather, it is only required that the pinch clamp body have a major and minor dimension which are different from one another. The pinch clamp  402  further includes a fastener hole  414  and a second part  416  of the alignment device previously mentioned (i.e., the one having a first part  408  on the lower bracket plate body  405 ). In the embodiment shown, the second part  416  of the alignment device comprises a pair of tabs  418  extending downward from the lower face of the pinch clamp body  412 . 
     The mounting bracket system of the current invention allows for a method of convenient installation of the rail body  102  to the vehicle. The mounting bracket  106  is first mounted to the vehicle using the top mounting bracket  114 . The top mounting bracket  114  may be configured to cooperate with pre-existing hold in the frame or sub-frame of a vehicle. In some instances it may be necessary that hole be drilled into the frame or sub-frame in the desired location to accommodate the mounting bracket  114 . When the bracket  114  is mounted, a fastener, such as a nut and bolt combination  420  and  422  may be inserted through the fastening holes  414  and  406  and loosely attached to one another to rotatably attach the pinch clamp  402  to the mounting bracket  106 . The pinch clamp  402  may then be turned relative to the mounting bracket top plate  404  until the major dimension with length W L  is aligned with the longitudinal channel  318  between the ends  314  and  316  of the rail body  102 . Because the fastener  420 ,  422  is only loosely fastened, the pinch clamp  402  can be lifted slightly from the surface of plate  404  to keep the first and second portions of the alignment device (in this case, tabs  418  and holes  410 ) from engaging. 
     The major dimension of the pinch clamp  402  with length W L  is selected to be larger than the width W c  of the rail body channel  318 , and the minor dimension with length W s  is selected to be smaller than the width W c . The major dimension and minor dimension are generally perpendicular to one another. Thus, when the major dimension having length W L  is aligned with the longitudinal channel  318 , the minor dimension having length W s  will be able to pass through the longitudinal channel  318  which has a width W c . In a preferred embodiment, the tabs  418  on the pinch clamp  402  are spaced a part by a width, denoted W t , only slightly larger than the width, denoted W b , of the lower plate body  405 . This will cause the pinch clamp  402  to remain aligned with the major dimension having length W L  aligned with the channel  318  without being held in this position. The rail  102  may then be lowered over the pinch clamp until the front and rear lips  310  and  312  of the rail rest upon the top of the body  405 . The pinch clamp  402  can then be raised slightly to disengage the tabs  418  from the sides of the body  405  and rotated 90 degrees until the major dimension W L  is generally perpendicular to the channel  318 . The two portions of the alignment device may then engage (i.e., tabs  418  will fall into holes  410 , maintaining the pinch clamp in position). Since the major dimension has a length W L  that is larger than the width of channel W c , the ends of the pinch clamp will overlie the front and rear lips  310  and  312  of the rail body  102 . Tightening the fastener  420 ,  422  at this point will draw the pinch clamp  402  against the lower plate  404  of the bracket  106 , securely capturing the rail body  102  and affixing it to the vehicle. It will be appreciated that since the rail body  102  has a generally uniform cross section along it&#39;s length, the rail body may be moved longitudinally back and forth for alignment purposes simply by loosening the fastener  420 ,  422 . It will not be necessary to completely remove the pinch clamp, rather just loosen it slightly so that the pressure between the pinch clamp  402  and the mounting bracket  106  is reduced somewhat. 
     Referring now also to  FIG. 36 , there is illustrated a block diagram showing a method for mounting a step rail and bracket system to a vehicle in accordance with another embodiment. Beginning at step  3610 , the mounting bracket  106  is mounted to a vehicle. At step  3620 , a fastener, such as a nut and bolt combination  420  and  422  may be inserted through the fastening holes  414  and  406  and loosely attached to one another to rotatably attach the pinch clamp  402  to the mounting bracket  106 . At step  3630 , the pinch clamp  402  may then be turned relative to the mounting bracket top plate  404  until the major dimension with length W L  is aligned along the length of the vehicle (i.e., along the length of the channel in the rail body when installed). At step  3640  the rail body  102  may be placed on the lower plate  404  of the bracket  106  such that the major dimension of the pinch clamp  402  with length W L  is within the longitudinal channel  318  between the ends  314  and  316  of the rail body  102 . Because the fastener  420 ,  422  is only loosely fastened, the pinch clamp  402  can be lifted slightly at step  3650  from the surface of plate  404  to keep the first and second portions of the alignment device (in this case, tabs  418  and holes  410 ) from engaging. At step  3660  the pinch clamp may be rotated approximately 90 degrees and lowered such that the first and second parts of the alignment device are engaged. At step  3670  the fore and aft position of the body rail  102  may be adjusted relative to the vehicle, and at step  3680  the fastener may be tightened. 
     Referring now again to  FIG. 4B , there is shown the mounting bracket system after the pinch clamp  402  has been fully tightened, capturing the rail body  102  between the pinch clamp and the lower plate  404  of the bracket  106 . It will be understood that while  FIG. 4B  illustrates the pinch clamp  402  positioned near the end of the rail body  102 , in fact the bracket  106  and clamp  402  may be attached at any point along the rail body  102  since the width of the channel W c  is substantially uniform along the length of the rail body. It will further be appreciated that since the pinch clamp  402  rotates to pass through the channel in the rail body, it is not required that the ends of the rail body  102  be opened during installation. Therefore, the end caps  104  may be installed on the rail body without interfering in any way with the installation of the rail body  102  on the vehicle. 
     Referring now to  FIG. 5 , there is illustrated an additional view of the pinch clamp  402 . It will be appreciated that the pinch clamp  402  is shown in an inverted position with respect to that shown in  FIG. 4A . In this embodiment, the pinch clamp  402  is rectangular having major dimension W L  and minor dimension W. It will further be appreciated that in this embodiment the pinch clamp  402  has a U-shaped cross section comprising a relatively flat center portion  422  and side rails  424  and  426 . This is a simple and strong configuration, however it is not the only configuration that will work. As previously indicated, other configurations having a major and minor dimensions as previously described may be used. The pinch clamp  402  may be pressed, cast, machined, or molded, and may be formed from steel, aluminum, alloys, or another material. In the embodiment of  FIG. 5 , the first portion  416  of the alignment device comprises tabs  418  separated by the distance W t . As stated, in a preferred embodiment, the width W t  is slightly larger than the width, denoted W b  of the lower plate body  405 . The tabs  418  may be pressed, punched, machined, or molded into the relatively flat center portion  422 . The tabs  418  represent only an exemplary second part  416  of the alignment device as other devices or methods may be employed. The fastener hole  414  may also be pressed, punched, machined, or molded into the flat center portion  422 . In the embodiment shown, the fastener hole  414  is square and designed to cooperate with the bolt  420  (of  FIG. 4A ), which may have a square neck so as to be self anchoring with respect to the pinch clamp  402 . 
     Referring now to  FIG. 6 , there is illustrated a side view of the mounting bracket  106  to further illustrate various aspects of the invention. The bracket  106  attaches vertically on the upper plate  114  to a vehicle frame, sub-frame, or other suitable mounting point. Holes  118  may be provided at such locations in the upper plate  114  as to match existing holes on the vehicle frame or sub-frame to which the bracket  106  will be mounted to allow the passage of bolts or other fasteners. A lower portion  120  of the upper plate  114  may also be angled to match the vehicle frame or sub-frame and may also be provided with holes for mounting the bracket  106 . In some embodiments the lower portion  120  may be angled to provide additional clearance or for aesthetic reasons. Other embodiments may not provide the lower portion  120 . 
     The bracket  106  also provides a lower plate  404  with a relatively flat body  405  which may be oriented in a generally horizontal position by the bracket arm  112 . The lower plate body  405  provides the first portion of the alignment device, which, in this embodiment, comprises holes  410 . The holes  410  may be the width W t  apart and positioned to match the tabs  422  of  FIG. 5 . Thus, the pinch clamp  402  may be held in position relative to the lower plate  404  by the use of a single fastener (such as the t 422  and bolt  420  of  FIGS. 4A-4B ) tightly fitted into holes  414  and  406 . Additionally, as previously described, the pinch clamp may be only loosely fastened to the lower plate body  405  and may thus remain rotatable when lifted from the lower plate  404 . The bracket  106  may be formed from steel, aluminum, alloys thereof, or other materials. The bracket  106  and its associated components and dimensions and may formed by machining, casting, molding, pressing, drilling, punching, and/or combinations of these and other methods. 
     Referring now to  FIGS. 7 through 15 , there is illustrated a roll formed step rail in accordance with another embodiment of the invention. The roll formed step rail  800  is substantially identical in most respects to that previously described, including a rail body  802  and end caps  804 . In this embodiment, however, step pads  807  and  808  have been added on the upper flat surface of the rail body  802 . In the preferred embodiment, the step pads  807  and  808  are mounted after the rail body  802  has been roll formed. The step pads  807  and  808  may be attached with adhesives, fastening studs, or other fastening means to the step rail  802 . The step pads  807  and  808  may be made from rubber, plastic, polymers, steel, alloys or other materials. The step pads  807  and  808  may be formed by molding, casting, or other methods. In a preferred embodiment, the step pads  807  and  808  may be formed of a slip resistant material and may be textured so as to increase the slippage resistance. 
     The end caps  804  may be made from rubber, plastic, polymers, steel, alloys or other materials. The end caps may be formed by molding, casting, or other methods. In the preferred embodiment, the end caps  804  are mounted after the rail body  802  has been formed. The end caps  804  may be attached securely with adhesives, fastening studs or other means. As previously described, the end caps may be installed on the rail body  802  prior to the rail body being attached to the vehicle due to the design of the mounting bracket system  106  and associated components. 
       FIGS. 10-15  provide various views of the completed step rail.  FIG. 10  is a side view illustrating the completed step rail  802  with step pads  807  and  808  and end caps  804 .  FIGS. 11 and 12  illustrate additional embodiments of the end caps  804  featuring non-slip texturing.  FIG. 13  illustrates another side view of the step rail  802  from the back side of the step rail  802  (i.e., the side that faces the vehicle following installation).  FIGS. 14 and 15  represent top and bottom view of the finished rail body  802 , respectively. 
     Referring now to  FIGS. 16 and 17 , additional embodiments of the step rail in accordance with the invention are shown.  FIG. 16  shows that the step rail  1600  may have a rail body  1602  of any length, and that two step pads  1607  and  1608  of any size may be used.  FIG. 17  shows that step rail  1700  in accordance with other embodiments may have a rail body  1702  of any length and a single step pad  1707  of any length. Each of the step rails  1600  and  1700  may be equipped with end caps  1604  and  1704  similar to those previously described. 
     Referring now to  FIGS. 18-24 , a roll formed step rail  1800  in accordance with additional embodiments of the invention is shown.  FIG. 18  illustrates a step rail  1800  that is provided without end caps or step pads. The step rail  1800  may be installed and used without end caps or step rails or may serve as an installation base to which items such as end caps and step rails may be added.  FIG. 19  illustrates a side view shown from the viewpoint of one facing the installed rail  1800 .  FIGS. 20 and 21  illustrate the respective end views of the rail  1800 .  FIG. 22  illustrates the back side of the step rail  1800  (i.e., the side that faces the vehicle following installation).  FIGS. 23 and 24  illustrate top and bottom views, respectively. 
     Referring now to  FIGS. 25-32 , further embodiments of the invention are shown. The step rail  2600  of  FIGS. 25-32  is substantially similar to the step rail  18  of  FIGS. 18-24 . From  FIGS. 25-32  it can be seen that the length of the step rail  2600  may be chosen according to the application and needs of the user or vehicle.  FIG. 26  illustrates the installed step rail  2600  while  FIG. 25  shows a cross section taken along the line  25  of  FIG. 26 .  FIG. 25  illustrates the cross section of step rails  1800  and  2600 .  FIG. 27  is a frontal view of the step rail  2600 , which may be of any length and  FIGS. 28 and 29  provide the respective end views of the step rail  2600 .  FIG. 30  illustrates the back side of the step rail  2600  (i.e., the side that faces the vehicle following installation).  FIGS. 31 and 32  illustrate top and bottom views, respectively. 
     Referring now to  FIGS. 33 and 34 , a roll forming operation for producing the step rail body is described in accordance with yet another embodiment of the invention.  FIG. 33  is a sequence of end views of rail profiles produced during the roll forming operation, showing the successive profiles of the rail body, from step A (original profile) to step Q (completed profile).  FIG. 34  is an alternative view of the profiles, showing the successive profiles of the rail body from step A to step Q from a fixed perspective. 
     Referring specifically now to  FIG. 33 , there is illustrated a sequence of end views (denoted A-Q) of the step rail body showing the sequential deformation of the original sheet during the roll forming process. In view A, the step rail body has the shape of a flat rolled sheet  3300  with a top surface  3303 , bottom surface  3305  and free ends  3314  and  3316 . Preferably, the flat rolled sheet  3300  is formed of an austenitic stainless steel, more preferably a  304  stainless steel having a nominal composition of 18% chromium and 8% nickel. The flat rolled sheet  3300  has a thickness (denoted T s ) which is preferably within the range from 15 gauge to 17 gauge (standard steel thickness) and more preferably 16 gauge. Stated another way, T s  is preferably within the range from about 0.0673 inches to about 0.0538 inches, and more preferably in the range from 0.058 inches to about 0.065 inches. 
     The top surface  3303  of the sheet  3300  is preferably pre-finished to its final appearance before roll forming. In preferred embodiments the original (i.e., pre-roll formed) top surface  3303  has a brushed finish with a typical surface roughness of Ra 40 micro-inches or less, and more preferably has a No. 4 Finish (ASTM) having a typical surface roughness of Ra 25 micro-inches or less. 
     Further, in preferred embodiments, the original top surface  3303  of the sheet  3300  is covered by a protective film  3307 , which protects the surface finish during roll forming. In more preferred embodiments, the protective film  3307  is a PVC (polyvinyl chloride) film secured to the top surface  3303  with a medium tack adhesive that allows the film to remain attached during roll forming, but can be removed manually thereafter. The protective film  3307  is preferably transparent so that the film and top surface  3303  can be visually inspected for the presence of undesirable debris or contamination before roll forming. 
     Referring still to  FIG. 33 , the originally flat sheet  3300  as previously described in View A is passed through a series of roll-forming stages as illustrated in Views B-Q. As is known in the roll-forming industry, each stage of the roll forming line has bending rolls that make a step-wise change to some portion of the cross sectional profile of the sheet  3300 , such that the sheet is gradually transformed from the original flat profile shown in View A to the fully formed profile shown in View Q. The changes between adjacent stages are small enough such that the sheet  3300  may be passed continually along the roll forming line without stopping between the original profile (View A) and the completed profile (View Q). 
     In a preferred embodiment, the initial bending stages (shown by Views B-E) sequentially deform the sheet  3300  beginning at the free ends  3314  and  3316  and forming substantially complete front and rear mounting lips  3312  and  3310  while the center section  3311  remains substantially unchanged (i.e., flat). Next, the intermediate bending stages (shown by Views F-M) sequentially deform the outer ends of the center section  3311  to substantially form the quarter circular rear curved portion  3308  and simultaneously partially form the semi-circular front curved portion  3306 . It will be appreciated that during the intermediate bending stages (Views F-M), the mounting lips  3310  and  3312  are not further deformed; rather their orientation simply changes as they “ride” on the respective curved portions  3308  and  3306 , which are being deformed. Next, the final bending stages (shown by Views N-Q) sequentially deform the front curved portion  3306  to its completed step rail configuration as shown in View Q. This final configuration is substantially similar to that previously described herein, e.g., in connection with  FIG. 3 , and includes all features of the step rail body including the channel  3318  of width W c . 
     Referring now to  FIG. 34 , there is illustrated an alternative sequence of end views (similarly denoted Views A-Q) of the rolled sheet  3300  as it is transformed from its original flat rolled configuration (View A) into the completed step rail profile (View Q). The views shown in  FIG. 34  are substantially identical to those shown in  FIG. 33 , with the views denoted using the same letter in the two figures corresponding to one another. In  FIG. 34 , however, the various views are depicted as if the center portion  3311  of the sheet  3300  was fixed in place. This provides a different perspective to allow further appreciation of the successive bending stages in the roll forming process. 
     After the sheet  3300  has passed through all stages (Views A-Q) of the roll forming operation, the formed sheet will have a substantially constant cross section of the desired step rail profile as previously described herein, e.g., in connection with  FIG. 3 . The formed sheet may then be cut to any desired length to form a step rail body. Any protective plastic film may then be removed from the outer surface of the body. Also, step pads and/or end caps may be added to the step rail body as previously described herein, e.g., in connection with  FIGS. 7-17 . The step rail may be mounted to a vehicle using a bracketing system as previously described herein, e.g., in connection with  FIGS. 4A ,  4 B,  5 ,  6  and  36 . 
     After roll forming, it is preferred, although not required, that the outer surface of the completed step rail exhibit a minimum surface finish that varies according to a position along the periphery of the rail body profile. This surface finish is preferably obtained without additional post-roll forming operations.  FIG. 35  illustrates such a minimum surface finish requirement diagram. 
     Referring now to  FIG. 35 , there is shown a cross-sectional view of a step rail body after roll forming to form a profile substantially similar to that previously described. The step rail body  3500  has a relatively thin rail wall  3502 , a relatively flat top portion  3504  disposed between a semi-circular front curved portion  3506  and a quarter-circular rear curved portion  3508 . A rear mounting lip  3510  extends forward from the rear curved portion  3508  and a front mounting lip  3512  extends upwards and then rearwards from the curved front portion  3506 . The respective free ends  3514  and  3516  of the front and rear mounting lips are generally in line with one another, but spaced apart as in previously described herein to define a longitudinal mounting passage  3518  having a predetermined width. It is understood, when mounted on the vehicle, the step rail will have the large curved (front) side  3506  facing the street and the small curved (rear) side  3508  facing the vehicle. In this embodiment, the roll forming process provides that, following the removal of any protective plastic film from the outer surface of the rail, the rail&#39;s outer surface will have particular minimum surface finish characteristics as follows. A first peripheral segment (denoted A in  FIG. 35 ) subtends approximately 160° angle from the upper rear of curve  3508  to the lower front of curve  3506  as shown. Segment A is the most critical to the appearance of the step rail. Segment A must be substantially blemish-free after roll forming. A second peripheral segment (denoted B) subtends approximately 45° angle from the lower front of curve  3506  to the edge of the front mounting lip  3512  as shown. Segment B is considered to have secondary importance to the appearance of the step rail. Segment B may have only minor to insignificant blemishes after roll forming. A third peripheral segment (denoted C) subtends approximately 45° angle from the upper rear to the lower rear as shown. It has tertiary importance to the appearance of the rail. In segment C, visual blemishes are allowed within a reasonable degree. Finally, a fourth peripheral segment (denoted D) subtends approximately 110° angle from the front mounting lip  3512  to the rear mounting lip  3510  (including the inner surfaces visible through the channel). Segment D is not considered important to the appearance of the rail. In segment D, visual blemishes which do not alter the product dimensions are allowable. Using the roll forming process of the current invention allows such minimum surface finish requirements to be achieved without requiring post roll-forming polishing operations. This has significant advantages in reducing production costs. 
     It will be appreciated by those skilled in the art having the benefit of this disclosure that this invention provides a roll formed step rail for a vehicle, a mounting bracket system, and process and methods relating to the fabrication and/or use of same. It should be understood that the drawings and detailed description herein are to be regarded in an illustrative rather than a restrictive manner, and are not intended to limit the invention to the particular forms and examples disclosed. On the contrary, the invention includes any further modifications, changes, rearrangements, substitutions, alternatives, design choices, and embodiments apparent to those of ordinary skill in the art, without departing from the spirit and scope of this invention, as defined by the following claims. Thus, it is intended that the following claims be interpreted to embrace all such further modifications, changes, rearrangements, substitutions, alternatives, design choices, and embodiments.