This invention relates, in general, to chassis, and more particularly to vehicular chassis and methods for their manufacture.
The automotive industry has grown to become one of the largest manufacturing industries in the world. Over the years, the basic structure of the automobile has changed little. Much like other heavy machinery, automobiles still generally employ some sort of standardized chassis that supports some sort of body structure and other components and subassemblies. Such conventional chassis generally comprise numerous metal pieces connected—usually by extensive welding—into a rigidly formed frame.
Modern day automobile chassis include a structure for supporting a body or are in some way integrated with a body. Exemplars of prior art automobile chassis are U.S. Patent Publication No. 2006/0237996 to Eipper et al. (“Eipper”) and U.S. Pat. No. 4,869,539 to Cassese (“Cassese”), both of which show a motor vehicle body and supporting structure. Eipper illustrates a body and modular supporting structure formed with roof columns to support a roof module. Cassese illustrates a vehicle with front, central, and rear frames joined together by connection devices.
The modern day automobile manufacturing process has evolved around the basic chassis/body architecture. Modern assembly plants include complex manufacturing equipment to position and weld pre-formed chassis parts together. The process for manufacturing automobile chassis is generally complex, time consuming, and capital intensive. By example, the typical chassis manufacturing system requires a large number of fixtures and welding stations. The fixtures hold individual pieces or assemblies in initial geometrical locations until they are welded into position. The chassis manufacturing system, therefore, involves many complex welding and adhesive processes which require expensive equipment, highly skilled workers, and valuable assembly floor space.
The manufacturing process increases in complexity exponentially as the chassis design increases in complexity. In contrast to a simple welded box frame, a typical space frame involves joining larger, modular components. Space frames generally include castings, extrusions, and sheet materials from pressings and roll forms interconnected to form a three-dimensional frame. Space frames and body-integral designs provide certain benefits over box frames; however, such designs can only be applied at a higher cost. Because of the capital-intensive nature of the manufacturing process, many designs become unfeasible at low volumes. The nature of the structure and joining process also limits its use to substantially-uniform materials. For example, aluminum can not be worked like steel, and welding steel to aluminum is difficult at best. The large manufacturing investment necessary with conventional chassis also limits manufacturing and design flexibility.
In addition to the above problems, there is a continual need to increase the efficiency of processes for manufacturing chassis structures. It is desirable to increase the strength-to-weight ratio of chassis at the same or reduced cost. Because the chassis serves as one of the primary supporting structures, the chassis has a significant impact on the overall performance of the vehicle. As an example, a “loose” chassis that lacks rigidity may sacrifice ride comfort by transmitting vibrations from the engine, wheels, and other working parts throughout the vehicle.
There is also a need to increase space efficiency. In a typical vehicle, especially in the automotive industry, “real estate” is at a premium and there are significant benefits when any space in the chassis can be made available for other uses. In other words, chassis structures may require high strength at minimal cost in light of dimensional limitations.
Other industries with machinery employing chassis encounter similar problems as the automotive industry. By way of example, a piece of heavy construction equipment, such as a backhoe, may not be as limited in terms of space as an automobile, but the chassis will be subjected to static and dynamic loads. The chassis structure will likewise require expensive manufacturing systems and processes to produce.
What is needed is a chassis and method of manufacture which overcomes the above and other disadvantages of known chassis.
The vehicle chassis and methods of manufacture of the present inventions have various features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated in and form a part of this specification, and the following Detailed Description of the Invention, which together serve to explain the principles of the present inventions.
a, 31b, 31c, and 31d are respective perspective, plan, front and side views of the vehicle chassis of
Reference will now be made in detail to various exemplary embodiments of the present inventions(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that the present description is not intended to limit the invention(s) to those
Turning now to the drawings, wherein like components are generally designated by like reference numerals throughout the various figures, attention is directed to
In some respects sub-assemblies and various components may be considered part of the chassis. In an exemplary embodiment, a suspension assembly 37 is mounted to the chassis (see e.g.,
The chassis of the present inventions may include other structures, components, and assemblies. In some embodiments, the body, or portions thereof, may be integrally formed with the chassis. As such, chassis may refer to a chassis frame with suspension, drivetrain, and other components as in “rolling chassis.” Chassis in accordance with the present inventions refers to a variety of chassis architecture including, but not limited to, a unibody construction, body-on-frame, space frame, monocoque, and combinations thereof. Hereinafter, ladder frame and chassis frame will be used interchangeably to refer to the network of beams and component members in the body-on-frame architecture that forms the structure upon which the body is loaded.
Chassis also refers to other design architectures and hybrid designs which bear resemblance to elements of the preceding architecture. As will be described below, the chassis of the present inventions may be configured to carry a load or configured to form or integrate with the overall vehicle or machinery product. For example, the chassis may include an integrated seat component, suspension system components, and the like.
Additionally, chassis may refer to structures, components, and assemblies beyond the normal usage of the term. As one example, chassis may refer to body panels and the like where the body panels play a structural role in supporting the load. Thus, in the case of a unibody construction for a vehicle, certain body panels may be play a significant role in providing torsional stiffness to the vehicle. Chassis thus may refer more broadly to components providing structural rigidity to the machinery and/or in communication with structural backbone of the machinery.
In one embodiment, chassis 32 is an automobile space frame with beams 42 (see, e.g.,
The following description will start by describing an architecture and approach for designing the architecture of a chassis in accordance with the present inventions. Next, exemplary chassis 32 will be described in further detail. Thereafter, the methods and various features of the present inventions will be described in more detail.
Turning to
Exemplary tub 44 is preferably formed by joining several sub-components, however, one will appreciate that the tub may be formed from one or more sheet materials. A firewall 46 extends upward and laterally at the front end of the tub, and a pair of front beams 42 extend from the front of the firewall. The firewall acts, in part, similar to a tubular space frame with each side of the firewall modeled similar to tube structures. An A-pillar further extends upward from a point, generally referred to below as a node, at the upper portion of the firewall. The A-pillar may be formed as part of the chassis, body, or both. Likewise, rear bulkhead 47 acts similar to a bar linkage at the rear portion of the tub. Further, C-pillars extend upward from the bulkhead. One will appreciate that the chassis may be configured such that B-pillars extend upward from the bulkhead or other portions of the chassis. In an exemplary embodiment, firewall 46 includes pillar slots 49 at each side to receive and position A-pillars.
In an exemplary embodiment, both bulkhead 47 and firewall 46 of tub 44 are formed from sheets of material prepared for bending along a plurality of bend lines and subsequently folded into three-dimensional structures. In contrast, tub floor 58 is generally a planar pan sheet. However, each of these components may be formed from a sheet, frame members, or other suitable methods and manufacturing processes. The floor and firewall form a common line of engagement 51 where they meet and intersect (see, e.g.,
For the purposes of the present invention, the term “node” refers to geometrical points in the chassis and/or along the load path. The node may be formed in the sheet of material, for example, the sheet forming the floor or the firewall. Alternatively, the node may be bonded to another structure or left free depending on the application. Bonding may be done by welding, adhesive bonding, mechanical fasteners and the like.
Exemplary chassis 32 makes use of cold and hot curing adhesives and rivet bonding to join component members. A separate component may also serve to connect the members such as a die cast component interconnecting edges of the firewall and floor. Further detail regarding the joining processes of the present inventions are provided below.
The front and rear portions of exemplary chassis of
Similar to firewall 46, other component members of chassis 32 may be formed from a sheet of material or by techniques such as roll forming, die casting, extrusion, pressing, hybrid techniques, laminating, and more. Each of the components members may also be joined thereafter using various joining techniques.
With particular reference to
The sheet folding approach of the present inventions allow for consolidation of parts. A conventional chassis design may call for a chassis tub having a frame with box beams, which chassis would often be formed by welding panel sides together into the box beams. Alternatively, the box beams may be formed by extrusion or by another process. The beams of the box frame are then welded together into the frame. In contrast, chassis frame 54 is formed from a reduced number of sheets, and preferably from one or more sheets of material. In this manner the process of manufacturing the chassis frame is simplified and improved. In contrast to conventional welding or extrusion, the described process allows for faster and simplified manufacturing. The method of the present inventions allows for precision folding such that box frames and the like may be accurately manufactured with reduced specification tolerances. The method of the present inventions may also provide other benefits such as greater design flexibility and increased rigidity as will be described.
Another approach to chassis design in accordance with the present inventions calls for increasing utilization of the processes and methods described to vastly increase the diversity of chassis designs available. The chassis architecture may be derived with little regard for the limitations of conventional techniques. The processes and methods that will be described below allow for greater manufacturing flexibility among other benefits which allows for designs not capable with conventional techniques. Thus, one may design a chassis based on any number of design guidelines in accordance with the present inventions. In contrast to conventional chassis architecture informed by long-held beliefs that a chassis must include specific design elements and must derive from a minimum number of materials and processes, chassis of the present inventions freely combine processes and materials. For example, chassis 32 combines beams with boxes and sheets. The structures and methods of the present inventions also allow for use of carbon fiber, foam, aluminum, steel, and other materials all dispersed within a chassis.
In various embodiments, the chassis design is based on hard or defined geometrical points or features dictated by the body design or performance parameters desired rather than structural or manufacturing limitations. “Geometrical points” and “geometrical features” refers to the design of the chassis as a structural element. In accordance with the description herein, “geometrical points” refers to loading points or load paths in the context of designing the chassis for loading. As described herein, the chassis may be designed in a manner similar to a truss whereby “geometric points” and “nodes” of the chassis corresponds to pins in a truss. The bend lines and edges of the chassis correspond to truss chords. In the context of designing the chassis for supporting a particular body design, and in particular a chassis integrated with a body, “geometric features” refers to aesthetic geometric features. For example, a bend line of the chassis along a side beam may correspond to a lower door sill in the exterior body, an edge of the chassis may correspond to a fender flare, and so forth. By a bend line “defining geometrical features,” it is meant that the bend line, an intersection of the bend line with another feature line, or an end of the bend line defines a geometrical feature.
In various embodiments, the chassis has features reflective of the desired aesthetic geometrical features (i.e. “A” surfaces) or the load points of the body on the chassis rather than manufacturing-dictated features. As an example, the chassis may include a bend line corresponding to an inflection point in the body rather than providing a specific component to create such an inflection. The design of chassis 32 may also be informed by the design and dimensions of the overall vehicle or the body. The described technology reduces or eliminates many conventional chassis design limitations. Thus, the body and other characteristics of the vehicle are not as limited by the standard chassis structure.
The design of exemplary chassis 32 begins by laying out the architecture in an initial sketch form (best illustrated in
With reference to
In one embodiment, tub 44 includes sub-components with varying structural configurations. For example, roof rails 56 are generally tubular or box-beam shaped but bulkhead 47 is generally a polygonal, three-dimensional structure.
In one embodiment, tub 44 is formed from several two-dimensional sheets of material 70. The sheets include a plurality of bend lines 72. The bend lines are defined by positioning structures 74. In an exemplary chassis 32, several components can or may be fabricated using folding technology.
The folding technology of the present inventions generally involves preparing a sheet of material with positioning structures that define a bend line. The positioning structures may be strap-defining structures, slits, displacements, grooves, or other structures that promote and facilitate bending. In many aspects, the sheets of material and methods of preparing such sheets are similar to those disclosed by U.S. Pat. No. 6,481,259, U.S. Pat. No. 6,877,349, U.S. Pat. No. 7,152,449, U.S. Pat. No. 7,152,450, U.S. patent application Ser. No. 10/821,818 (Pub. No. 2005/0005670), U.S. Pat. No. 7,032,426, U.S. Pat. No. 7,263,869, U.S. Pat. No. 7,222,511, U.S. patent application Ser. No. 11/357,934 (Pub. No. 2006/0261139), U.S. patent application Ser. No. 10/952,357 (Pub. No. 2005/0064138), U.S. patent application Ser. No. 11/384,216 (Pub. No. 2006/0207212), U.S. patent application Ser. No. 11/080,288 (Pub. No. 2005/0257589), U.S. patent application Ser. No. 11/374,828 (Pub. No. 2006/0213245), U.S. patent application Ser. No. 11/180,398 (Pub. No. 2006/0021413), U.S. patent application Ser. No. 11/290,968 (Pub. No. 2006/0075798), U.S. patent application Ser. No. 11/411,440 (Pub. No. 2007/0113614), U.S. Provisional Patent Application No. 60/665,577, U.S. patent application Ser. No. 11/386,463 (Pub. No. 2006/0277965), and U.S. Provisional Patent Application No. 60/854,846, which are each incorporated herein by reference in their entireties (“related applications”). In these applications several techniques and manufacturing processes for forming positioning structures that will precisely control bending of sheet material are disclosed. The emphasis in these related applications is in connection with the use of slits, grooves, and displacements which provide control bending.
In one embodiment, positioning structures 74 are strap-defining structures that define a bending strap 75 having a longitudinal strap axis 77 oriented and positioned to extend across the bend line. Additionally, the positioning structures may be configured in accordance with particular manufacturing or performance specifications. In one embodiment, the positioning structures are slits and a plurality of the structures include a central portion extending along the bend line and stress-reducing structures at end portions thereof. In one embodiment, the positioning structures have end portions that curve away from the bend line such that adjacent pairs of bend-facilitating structures define bending straps therebetween. The bending straps may further extend obliquely across the bend line.
Positioning structures 74 may be adjusted or modified in accordance with the present inventions. In an exemplary embodiment, the positioning structures on beam 42 are slits with central portions extending along the bend lines and end portions diverging away from the bend line. At least one of the positioning structures further includes ends that curl and return back towards each other thereby advantageously directing stress concentrations to neutral zones in the material during bending. As described in the '398 application above, which is incorporated by reference, such a structure yields increased fatigue resistance. The position and dimensions of the positioning structures on an exemplary beam are further selected to suit the particular application. In an exemplary embodiment, the positioning structures are strap-defining structures similar to those disclosed in the related applications. The positioning structures along the length of beam 42, therefore, define straps of varying widths and dimensions. Along the middle, the straps are narrower for decreased bending resistance. Closer to firewall 46, the straps are wider for increased bend line rigidity.
In one embodiment, the strap-defining structures may be configured to create a crumple zone. In an exemplary embodiment the strap width is thin in the front and generally increases moving in a direction towards the rear along front beams 42. Alternatively, the frequency of the straps along the length of the structure may increase towards the rear. Thus, in an impact, the front of the front beams will collapse and absorb impact energy. The front beams and other chassis components may be configured in similar manner for impact and other conditions outside of normal operating conditions. Many other modifications and adjustments may be made to the chassis depending on such factors as loading arrangements, bending and manufacturing concerns, and performance specifications. Similarly, such modifications may be made to any other component in the chassis as will be understood from the description herein.
In an exemplary embodiment, positioning structures 74 form at least one bend line within a sheet material and extend along an edge of chassis 32 once the sheet material has been bent. In an exemplary embodiment, rocker beam 61 is formed in part from a two-dimensional sheet folded along the bend lines. Thereafter, the three-dimensional structure is connected to other components to form tub 44 and chassis 32.
With reference to
Turning to
Geometrical feature may correspond to features other than body aesthetics including loading features and chassis design features. Referring to the figures, the exemplary chassis in
Chassis 32 may also be considered a network of nodes and connecting lines. For example, points where lines or edges of the chassis change directions distinctly may be considered nodes. The faces or sides of beam 42 and other structures form the connecting lines or chords. These points may also define physical features of the chassis or vehicle such as inflection points in the vehicle body. These points may define geometrical features such as mounting points or physical limitations of the chassis.
Such points at which connecting lines change direction also by their nature define features of the load paths. For example, an offset, longitudinal load along an edge of the chassis will impart related linear loads in the x-y-z directions and a moment. The points at which the load path is transformed or changes direction may also be referred to as a node. These points are generally defined by changes in the architecture of the chassis. For example, a flat structure may intersect a perpendicular structure and the load will be said to travel around the corner.
In various embodiments, the chassis architecture of the present inventions takes advantage of the above principles by maintaining substantially linear paths between loading points. In one embodiment, any transition point between linear paths is gradual and abrupt transitions or sharp corners are minimized. The transitions promote desirable distribution and control of loads in the structure. In an exemplary embodiment, transmission tub 44 includes a tunnel intermediate panel 79 between tunnel 81 and firewall 46. Among other things, the tunnel panel provides a smooth longitudinal transition between the path along the tunnel walls and the panels or faces of the firewall.
With reference to
In one embodiment, the load path emanating from each wheel 35 is substantially linear such that the loads from the front and rear wheels are directed towards each other. This means that the load applied to the chassis from wheel loading creates a sagging load. The compressive forces from the sagging load are thus directed in-line towards each other. The top plane of the chassis would thus be substantially in compression with minimal moment forces created.
In a conventional chassis, the load path veers and turns at each point where tubes or planes meet. Such points may be weld points, die cast junction components, bosses, or any other junction configuration. In contrast, the chassis configuration of the present inventions makes advantageous use of the characteristics of standard materials by subjecting the materials to compressive forces and minimizing torsional or bending forces on the material. This configuration makes efficient use of the properties of the materials employed.
As described above, chassis 32 may be formed in part from sheets of material similar to sheet 70. Such sheets may be folded into various component products including, but not limited to, tube-like structures similar to tubes found in traditional body-on-frame chassis, larger three-dimensional structures similar to a firewall in a space frame, or body structures and panels in the case of unibody or body integral chassis.
In one embodiment, at least one chassis member is formed from a sheet of material having a plurality of bend lines and at least two of the bend lines are configured and positioned such that upon bending the at least two bend lines define a hard geometrical point in the chassis architecture. The bend line may define a hard line or soft inflection in the chassis architecture. A hard line refers to a something like a rigid edge (e.g.
Chassis 32 may also have a hybrid design incorporating features of a truss and space frame or unibody. In one embodiment, the chassis is modeled similar to a truss and the design of the chassis is informed by the functional features of the truss model. Chassis 32 of
The loading of such components may be modeled with simplified modeling guidelines. Although not intended to be an accurate illustration of actual loading, such guidelines may facilitate the design of chassis architecture. By simplifying the load paths through the chassis, the chassis may be modeled similar to a plane truss or space truss where the edges of the panel of the chassis space frame are treated like truss chords.
The relevant components are first identified. Anything that can take a load will take a load. For example, soft elastic material may be used for sound-deadening or other purposes throughout the chassis. Such materials will not absorb or support a significant load. On the contrary, components likes bulkhead 47 will take a load and thus may be configured specifically to support and receive loads on chassis 32.
It has been found that loads applied to such load-bearing components, in general, travel primarily along edges of the components to corners. In a three-dimensional structure, the load will tend to move to the edges rather than traveling through the panels. The load path may further be modeled by treating the load as moving along the longest load path.
Chassis 32 involves a plurality of angular structures that form corners in the structure. Such structures meet at as junctions. Further, individual components and assemblies may include junctions, which may also be referred to as apexes. In the context of the chassis geometry and load analysis, such junctions also define nodes as described above. A sharp angle formed between members meeting at a junction point may lead to failure. Sharp angles may also lead to a high moment at the junction. Therefore, chassis 32 may be configured to reduce the occurrence of junctions and apexes with sharp angles to advantageously manipulate the load path through the chassis.
With the above principles, exemplary chassis 32 may be understood as being configured as a cantilever beam with a truss-like structure. Viewed from the side of the vehicle (best seen in
In one embodiment, the firewall and/or bulkhead are configured to support a moment load along the top or bottom load path of chassis 32. In particular, the firewall or bulkhead includes a panel connected to the load path to counter the “sagging” load by translating moment into a tensile or compressive load in the direction of the panel.
In one embodiment, the panel edges are treated as chords of a truss. Thus, the panels are angled with respect to each other such that the sum, in the aggregate, of all horizontal, vertical, lateral, and moment forces are minimized, and more preferably substantially equal zero. Further, substantially vertical members may be selected to withstand shear forces in the truss web. The analysis of the chassis in this instance may proceed by analysis of the chassis load paths along nodes defined by the junction or intersection of planes, beams, or other members of the chassis. In this case, the nodes may be treated as hinged members. Alternatively, the corners of the structures or connection between separate members may be configured to support a load or moment.
One will appreciate that the panels may be provided with apertures or openings 85 to reduce weight of the panels while still maintaining the truss-like structural integrity of the structure (see, e.g.,
With reference to
Similar to transitions employed by quilted apexes 86, flare 82, and the like, the larger chassis members may also include transition zones. With particular reference to
The respective components of exemplary chassis 32 may now be described in greater detail. An exemplary chassis is formed by joining three-dimensional structures primarily formed by bending sheets of material. At the outer limits, front and rear bumpers 53 extend laterally at ends of front and rear beams 42. The bumpers are formed from a single sheet of material 70a (shown in
Front beams 42 lie aft of the front bumper. The front beams join to the bumper by front beam-bumper flanges 88. In an exemplary embodiment, the members are joined together through a rivet-bond and adhesive. Other fastening methods may be employed depending on the application requirements.
In an exemplary embodiment, the joint between the front beams and front bumper includes optional T-shaped patch plates 89. The patch plates fasten to the front beams and bumper to further secure the joint. Although the patch plates serve to hold the two members together, patch plates 89 primarily maintain alignment between the bumper and beams. In the event of an impact, the patch plate maintains the bumper in alignment so that the compressive force is transmitted from the bumper straight into the beams. This is especially the case for impact forces at an angle. The top and bottom surfaces of beams 42 resist shear forces, but the beams may be subjected to extreme lateral forces if the bumper were to come out of alignment.
The front beams are formed from a single sheet of material 70b. The sheet of material includes four panel portions 84b corresponding to the four panels or sides of the folded beam. The panels are defined by bend lines 72b. The sheets of material further include bend lines at each end defining flanges 88b. Along the perimeter, two bend lines further define front beam connection flanges 88b′.
The front beams are formed by folding sheet of material 70b along the bend lines. The method of folding and sheet of material are similar to those disclosed in the above-mentioned applications, incorporated in its entirety herein. With particular reference to
Front beams 42 fasten to tub 44 at one end. With conventional chassis, members are welded or bonded together. In the most typical case, each piece is individually bonded to another piece. Therefore, precision welding is critical to the joining process with conventional chassis. Additionally, the pieces to be joined must be of material types amenable to the bonding process. For example, a plastic piece generally cannot be welded to a steel tube. With the chassis and joining structure of the present inventions, however, joining may be accomplished by and among many different types of materials and manufactured parts. The precision folding technology of the present inventions eliminates the need for many joints and joining processes. Many sections of the chassis may thus be formed as discrete modular components and thereafter joined with conventional methods such as rivets.
In general, the components forming chassis 32 may be joined together in a variety of configurations. Referring to each side of the components as panels, the components may be joined panel-to-panel or with an open configuration. In the panel-to-panel configuration, a panel of a first component member lies substantially flat against a panel of a second component member. When joined together, the adjoining panels form a rigid backbone to the joined structure. In an open configuration, at least one of the component members has an open side that aligns with the other component member. Adjoining component members may be joined in various other configurations either directly or indirectly. The joined member may also share less than a full panel surface in common such as common edge or corner. The members may also be joined through an intermediate member. Depending on the application, other joining configurations may apply.
In an exemplary embodiment, front beam-tub flanges 88b″ provide a fastening surface to the tub in an open configuration. The flanges fasten to a front surface of firewall 46. The beams may be provided with a closed end, for example by an end flap along another bend line, to increase the fastening surface area. In an exemplary embodiment, the firewall surface is configured to align with the end of the beams. In particular, the angle of the firewall substantially matches the angle of the end of the beams when joined thereto. Other configurations are also envisioned included a slot for receiving the beams.
In an exemplary embodiment, firewall shroud 60 wraps around the connection between firewall 46 and front beams 42. The shroud is formed from a single sheet of material folded along bend lines much like other members of the chassis. A top surface 91 of the shroud extends from a top of the firewall to the front beams (best seen in
With specific reference to
In the folded configuration, firewall 46 includes a skeletal structure similar to front beams 42. In an exemplary embodiment, the firewall includes material overlap along the joint between side beams 95 and instrument panel 96. As shown in
The firewall is configured to join with several other members of the chassis and vehicle body. Side beams 95 include apertures 49 configured to receive an A-pillar or other structural member to support a windshield and roof rails. An exemplary firewall is configured to receive and route electrical components such as wiring harnesses. Because the firewall structure is essentially hollow, the wiring harnesses may be routed through apertures 49 and up to the instrument panel. Similarly, the firewall and other chassis members may be configured for any number of other applications.
Firewall 46 and shroud 60 of an exemplary chassis are configured to increase rigidity in addition to their functions as mounting members and the like. With reference to
Tub 44 includes a nosecone 98 that provides a transition between the firewall and tunnel 81 in the floor. The nosecone is formed from a single sheet of material and joins to the other chassis members with flanges much like the members described above. The nosecone serves several purposes. The nosecone may provide a cosmetic covering at the front of the passenger cab over the transmission or other systems. The nosecone also increases the strength of the chassis, in particular, the transfer of loading from the tunnel and floor to the firewall.
In an exemplary embodiment, the firewall is configured to receive and position the nosecone. The firewall includes a flange bend line just below the instrument panel that forms a crook into which a top surface 100 of the nosecone fits.
Turning to
In an exemplary embodiment, rocker beams 61 are not separate members of the chassis but instead are monolithically formed with at least a portion of floor 58. In an exemplary embodiment, tub 44 includes a floor section 105 comprising tunnel 81, floor pan 107, and the rocker beams. The floor section is formed from several sheets of material 70e folded and joined together. In the alternative, the floor section may be formed from a single sheet of material. In one embodiment, the floor section is single body having a cellular structure defined by a core 110 sandwiched between two substrates 112 (best seen in
Sheets of material 70e of material are joined similar to the chassis members described above. The sheets further include floor joining flanges 88e that create an overlap configuration in the joining region to further secure the bent sheets together.
With reference to
In an exemplary embodiment, firewall 46 and bulkhead 47 are configured to receive and join with the tunnel. A bottom portion of the firewall includes a cavity 109 that is dimensioned and configured to match with the tunnel geometry. Thus, a front end of the tunnel fits with and is fastened to the firewall. The tunnel is further joined to the firewall by nosecone 98 and tunnel flanges 88f The bulkhead includes a similar configuration. In this manner the tunnel in conjunction with the rocker beams rigidly joins the bulkhead and firewall into a rigid lattice structure in the middle portion of the vehicle.
In an exemplary embodiment, tunnel 81 includes additional strengthening mechanisms (best seen in
Additionally, tub 44 in accordance with the present inventions may optionally include supplemental members for increasing rigidity. In one embodiment, cross-members 114 extend laterally across the tub from door-to-door (shown in
In the case of convertibles that do not have a roof section, the tunnel and rocker beams are often the only members that extends longitudinally along the middle of the vehicle. Furthermore, in some cases it may be desirable to have rocker beams with a shorter height or thinner width to make it easier to step over the door sill and gain entry to the vehicle. In these cases conventional chassis requires substantial modifications to the chassis. Such modifications include increased material in the A-pillar and C-pillar regions and strengthening of the floor with cross-bracing, additional thickness in the floor, and other methods. These methods increase manufacturing complexity, material cost, quality control issues, and weight. The tub section in accordance with the present inventions achieves sufficient rigidity without the use of such complex methods.
The rear end of chassis 32 is configured similar to the front end. Bulkhead 47 may be formed from one or more sheets of material similar to the firewall. Also, the bulkhead may be similarly configured to rigidly join with rocker beams 61 and tunnel 81. In an exemplary embodiment, the bulkhead may have a cellular structure similar to that of the tunnel.
A pair of rear beams 42′ join with the bulkhead in the rear of the vehicle. The rear beams are formed similar to the front beams. In contrast to the front beams, however, the exemplary rear beams have a mid-plane closing configuration. A sheet of material 70g includes rear beam flange ends 88g. The sheet is configured to fold such that the flange ends meet in the middle of one side of the resulting structure as opposed to along an edge. This configuration takes advantage of the fact that in many applications failure occurs along the edges of the structure. Failure is less likely to be caused by buckling of the plane. The same configuration may be used to form the front beams and vice versa.
The rear beams are joined with the bulkhead similar to the front beams. The joint lines on the top and bottom surfaces of the rear beams and bulkhead further include optional patch plates 89 to stiffen the joint. With reference to
Many of the above-described features blur the line between structural and aesthetic members. For example, shroud 60 may be configured to support an instrument panel 96 while at the same timing serving as a significant structural member of chassis 32.
Each section of chassis 32 may include a three-dimensional structural member formed from a sheet of material have a plurality of bend lines. Each bend line is defined by a plurality of positioning structures as described above. In one embodiment, the chassis section further includes a plurality of nodes with each node positioned along one of the plurality of bend lines. Each node in turn defines a geometrical feature of the structure. In one embodiment, a junction between at least two of the plurality of bend lines is configured and positioned to define one of the plurality of nodes. The junction may be defined by an intersection of at least two bend lines or an intersection of adjacent panels, tube-like members, or the like.
As discussed above, an exemplary chassis is composed of several separate component members joined together. The general method of joining these chassis members may now be described more broadly.
In one embodiment, at least one of the chassis members is formed from a sheet folded along bend lines. A second member is joined to the folded first member. The two members may configured to join together to form a node of the chassis. In one embodiment, the bend lines of the first member, and optionally the second member if it includes bend lines, defines a plurality of geometrical features of the resulting section of the chassis formed by the joining of the two members. The chassis members may be also be joined in other configurations. In one embodiment, the chassis members join together to form a unibody chassis construction.
The chassis members do not need to be joined end-to-end or with a common line or edge of engagement either. In one embodiment, a first chassis member is wrapped by a sheet of material having bend lines. The bend lines may correspond to desired geometrical features of the resulting vehicle or chassis, such as curves and inflections in the body architecture. Alternatively, the bend lines may correspond to physical edges of the first chassis member to be wrapped. Such a configuration allows for nesting or wrapping and can be used to increase rigidity, create complex shapes, and other applications. Other configurations may also be employed depending on the application.
In addition to chassis 32, a typical motor vehicle includes many other stationary and working assemblies. Vehicle 30 includes several component members and subassemblies in connection with the chassis (best seen in
The component members may be secured together by several methods. Such methods include, but are not limited to, adhesives, welding, mechanical fasteners such as rivets, and/or other suitable fasteners. In an exemplary embodiment, chassis 32 employs several joining configurations. For example, in the front of the chassis, shroud 60 includes at least one aperture configured to receive ends of beams 42. The apertures serve to align and hold the beams in position at least temporarily until permanently joined together. Several component members include joining flanges 88 configured to fasten the two components together.
In one embodiment, at least one structure serves secondarily as a fastener for two distinct components. In an exemplary embodiment, front tower rails 39 are connected at one end to the front of beams 42 and at an opposite end to at least one of shroud 60 and firewall 46. Therefore, although the primary function of the front rails may be to support suspension towers 40, the front rails serves the secondary function of supporting and joining together front beams 42 to the rest of the chassis.
In an exemplary embodiment, beams 42 are joined together cross-wise by bumper 53. The bumper is joined to the end of the beams through the use of several joining techniques. The bumper and beam are joined together through the use of flanges and/or adhesives similar to the joining of the beam to the shroud. Further, joining flanges 88 on the beam include rivet holes for rivet-bonding to the bumper.
It should be noted that the size, shape, and configuration of joining flanges 88 will vary depending on the application. Accordingly, the flanges to attach beams 42 to bumper 53 vary from those configured to attach the beams to tub structure 44. In one embodiment, the flanges are further configured to provide a smooth transition between panels of adjoining components. In an exemplary embodiment, the junction between transmission tunnel 81 and firewall 46 includes flanges with an angle of incidence intermediate that of the tunnel and firewall. Additionally, the flanges may be configured to reduce stress at the junction between components. The flanges may have a larger shape or outer dimension to direct stress away from the zone of engagement of the two components. The method of securing the flanges and the like should also be taken into consideration. By way of example, the flanges may be configured to advantageously move rivet holes away from the connection between the components.
In an exemplary embodiment, the joining of the two components is further reinforced by the attachment of at least one patch plate 89. Multiple plates may be provided in a stacking structure. The two plates may be configured to reinforce the joint between the components with differing shapes, thicknesses, and the like. Each plate is optionally fastened to the two components independently of the other plate.
It should be noted that the above joining methods generally relate to permanent joining of members. However, depending on the application, it may be desirable to releasably join members or only temporarily join members. Furthermore, folding and manufacturing technologies described may be employed for self-fixturing processes upstream of a final forming station as will be described in greater detail below. A conventional method employs fixtures to hold parts in position. In one embodiment, the first and second component members are joined together without the use of fixtures and similar mechanisms.
Several strengthening features have been described above in relation to particular chassis members. Such features will now be described in more detail below in regards to the entire chassis 32.
As described above, floor 58 includes a cellular core 110 sandwiched between film structures 112. In an exemplary embodiment, the cellular core is a sheet of material bent along bend lines into a corrugated sheet and sandwiched between two sheets of material. The core may also be configured with alternative structures. In an exemplary chassis 32 at least one of the components includes a sandwich structure with a honeycomb-shaped core.
The bulkhead may be filled with a filler material 117 (see, e.g.,
As with most any dynamic structure, chassis 32 may experience forces from harmonics. The presence of many planar sheets in the structure may lead to increased stress on the structure. In one embodiment, filler material is placed inside of at least one member of the chassis such that the natural harmonic is dampened. Other dampening configurations may be used depending on the application.
In an exemplary embodiment, tunnel 81 includes laminate panels. Each laminate panel includes a substrate with a structural material 116 deposited on the substrate surface. In an exemplary embodiment, the substrate is a non-compressible sheet of material having bend lines and the structural material covers at least the bend lines. The substrate is bent along a desired bend line into a three-dimensional structure. Either before or after bending, the structural material is deposited to the substrate. Thereafter, the structural material is allowed to cure thus forming a rigid structure with laminated panels and stiffened bent edges. The laminate structure thus has at least two layers: a first layer with a bend line and a second layer of the structural material. The layers do not need to be substantially flat. Depending on the application the shape and configuration of the layers may be modified.
The laminate may be manufactured “in situ.” In one embodiment, the sheet of material 70e is folded along the bend lines and positioned in a mold or similar device. Thereafter, the structural material is deposited on the sheet. In such case, the structure may be formed with a fastener 115 integrally connected to the sheet of material by the structural material, the fastener being positioned relative to the sheet prior to application of the structural material as is shown in
The presence of the rigid structural material over the bend line provides the additional benefit of preventing flutter. Flutter refers to lateral movement of one of the bent sides relative to the other bent side and results generally from stretching and compressing of the bending webs or straps along the bend line.
Structural material 116 for the laminate may be a variety of different materials. Suitable materials include, but are not limited to, adhesives, polymers, resins, wood, and composites. In an exemplary embodiment, at least one panel of the bulkhead carbon fiber is used as the structural material.
In one embodiment, the structural material is further configured to seal the bend line. Sealing refers to water resistance, electromagnetic shielding, prevention of other tangible or intangible matter from passing through the bend line after bending, and the like. In one embodiment, structural material 116 is configured to fill gaps in the bend line formed by the bend-facilitating structures.
Structural material 116 may also be a rigid material placed over a bent substrate sheet. In this case, the structural material is formed from a sheet of material bent about a bend line. The sheet may positioned along the substrate before or after bending such that the substrate bend line and structural sheet bend line are substantially aligned.
The structural material and substrate form a rigid, layered, bent structure referred to herein as a laminate panel. The resulting structural having a laminate bend line and/or a partially laminated panel side is referred to herein as a laminate structure. The resulting laminate structure is joined to the rest of chassis 32 similar to other components as described above.
In one embodiment, the structural sheet of material includes at least two bend lines configured to create a gap between the structural sheet and the substrate bend line. The gap is then filled with a filler material. In one embodiment, a quilted corner is filled with filler material. Suitable filler materials include, but are not limited to, foam, compressed air foam, resin, adhesive, wood, polymers, and epoxy. The resulting laminate may also be filled with a filler material as described above. As will be appreciated from one skilled in the art from the foregoing, various components of chassis 32 besides tunnel 81 and floor 58 may be prepared with laminate structures, filler materials, and the like. Further details regarding such materials and structures in accordance with the present invention will be described below with reference to
Additionally, the components and sections of chassis 32 may optionally include treatments depending on the application. Such treatments include, but are not limited to, adhesives, coatings, and physical structures. For example, in some applications it may be desirable to apply a water sealant or paint to the bend line or an entire panel after folding. Further, a filler material may be optionally applied between the substrate bend line and structural material bend line.
Structures and configurations similar to the floor and bulkhead described above may be employed throughout chassis 32. A combination of these structures may also be employed. For example, firewall 46 may be formed with laminate sides and a cellular core. The structure may be further modified with optional structural fillings and treated with coatings and the like.
Generally, the chassis of the present inventions results from use of any number of the above described structures in various portions. Different considerations will drive the design of individual components, subassemblies, and larger sections of the chassis. Therefore, the particular configuration used in any area will often vary from another area of the chassis.
As will be understood by one skilled in the art, the configuration of the floor, tunnel, cross-members and many other components of the chassis requires consideration of many factors such space requirements, loads and performance characteristics, and cost. For example, some vehicles may limit the space for seating and/or have lower stiffness requirements such that cross-members 114 and the like are not employed. It will be understood by the above that the chassis and component members may be modified and adjusted in accordance with the present inventions in view of many such considerations.
Similarly, the chassis configuration may be modified in accordance with loading requirements. In one embodiment, a suspension loading point is located inside of beams 42. Likewise, the volume inside of all of the three-dimensional folded structures may be utilized for a varying of applications.
As describe above, chassis 32 may be formed of a variety of materials and structures utilized and joined in myriad fashion. Referring to
Layer 225 may be affixed or adhered to sheet 220 in various ways. In various embodiments, only part of layer 225 is affixed to sheet 220. For example, only a portion of layer 225 adjacent to the bend line may be affixed to sheet 220 and the rest of laminate sheet 221′, including the bend line area, is left free. In such a case, a pocket may form between the bend-controlling structures and layer 225, such as a space between a displaced portion of the sheet and an adjacent portion of the layer. Laminate sheet 221′ may be configured to account for spring-back in sheet 220, for example, layer 225 may be an elastic material to accommodate variations in the bend angle.
Sheet 220 is shown with bend-controlling displacements 222a′ and 222b′. In various embodiments, the bend-controlling structures are grooves which have been chemically etched into a metal or plastic sheet. When the etching process reaches the top surface 219 of sheet 225, etching can be stopped, for example, by neutralizing the etching chemicals or by the adhesive layer which bonds layers 220 and 225 together, or by the chemical inertness of the material of layer 225, as compared to the chemical reactivity of layer 220. Grooves 222a′ and 222b′ correspond to grooves 222a and 222b in
The grooved laminate sheet 221′ may have bending webs 226′ that are ductile and facilitate bending in the same manner as shown in
Laminate sheet 221′ of
Referring generally to FIGS. 33B and 35-41, sheet 220 may be configured as a control surface whereby sheet 220 primarily controls the bending process. For example, layer 225 may be a flexible material or of a configuration that bends easily and sheet 220 of a rigid material. Thus, during bending, the rigid sheet and bend line precisely define where bending occurs. Layer 220 may be a material providing resistance to bending, for example, to provide tactile feedback or to further control and facilitate bending.
In various embodiments, layer 225 is selected and/or configured to provide aesthetic characteristics or to protect sheet 220. By example, larger bend-facilitating structures such as displacements lead to discontinuities in the outer surface after bending. Such discontinuities may be more readily apparent with sharper bends than smooth curves. Layer 225 may be selected to provide a smooth, protective outer surface over the bend line in sheet 220. As shown, for example, in
Suitable materials for layer 225 include, but are not limited to, silicone, neoprene, flexible metals, and rubber. In various embodiments, the material of sheet 220 has a higher strength and/or lower ductility than the material of layer 225. The layer may have different characteristics depending on the application. For example, layer 225 may be a transparent material to provide visual cues of sheet 220 underneath. Similar materials may be used for sheet 220 as sheet of material 221, but the laminate structure described herein provides greater flexibility in choice of materials and configurations. Layer 225 and sheet 220 may also be the same material depending on the configuration. For example, sheet 221′ may be formed from a layer of thin metal laid over a thick piece of the same material. In various embodiments, sheet 220 is at least twice the thickness of layer 225.
Layer 225 and/or sheet 220 may be treated and prepared to suit particular applications. In various embodiments, layer 225 and/or sheet 220 have integrated color (e.g. color dye) prior to forming of laminate sheet 221′. In various embodiments, the laminate sheet is finished before or after bending. Finishing may include spot welding, sealing, polishing, sanding, and the like of the bend line or outer surface after folding.
While laminating is described as a step prior to forming the bend-controlling displacements, it will also be understood that layer or sheet 220 can be cut through to form slits and layer 225 laminated or adhered to layer 220 after the slitting occurs. This converts the slits to grooves in which there is a continuous membrane or web 226 across the bottom of what was slits. Laminate sheet 221′ also could have more than two layers, and grooves 222a′ and 222b′ could penetrate less than all the way through upper layer 220 or into lower layer 225, depending on the bending effects desired.
Sheet 220 may be provided with various bend-controlling structures as noted above. Bend-controlling structures 222a′ and 222b′ may be slits, displacements, grooves, and similar structures. The bend-controlling structures may also be mere gaps in the material or similar areas of weakness that promote bending. In such a case, the layer may be configured to hold and pull the sheet together across the area of weakness.
The bend-controlling structures may be formed by laser cutting, water jet cutting, punching, stamping, etching and other processes as would be understood by one skilled in the art from the foregoing description. Such processes for forming bend-controlling structures are described in depth in U.S. Pat. Nos. 6,481,259, 6,877,349, and 7,152,449, all of which are incorporated herein for all purposes by reference thereto.
The bend-controlling structures may be formed prior to forming the laminate sheet or after preparing the laminate sheet in the flat. For example, laser cutting techniques or other techniques may be used to create a bend-controlling structure in sheet 220 through layer 225.
In the case of a laminate sheet with a flexible, elastic outer layer 225 and hard sheet 220, the bend-controlling structure may be punch or cut through the layer 225 without piercing the layer. The sheet 220 may also be provided on top of layer 225, which provides easier preparation of sheet 220, or laminate sheet 221′ may be formed and prepared “upside down” and flipped over during assembly.
The process of forming bend-controlling structures and the type of structure may depend on the application. It has been found, for example, that laser cutting provides a smoother surface than punching and thus may be more desirable in applications where a smooth outer surface is desired and the bend-controlling structure is not adequately masked by layer 225.
Laminate sheet 221′ may also be formed with multiple layers (shown, e.g., in
Referring to
Referring to
Referring to
As shown in
The selection of materials for the layer or use of additional layers may be based in part on a desire to mask bumps, colors, and other imperfections in underlying surfaces. For example, an opaque or more rigid material may be used for such cosmetic purposes.
Layer 225h is a flexible material such as neoprene that covers the bend-controlling structures after bending (best seen in
The method of manufacturing the chassis in accordance with the present inventions in comparison to conventional chassis will now be described. With conventional chassis manufacturing systems, each individual piece of the chassis to be formed is positioned and then held in an initial position by a fixture. Thereafter the piece is welded by a machine or by a skilled worker. In order to keep parts within specified tolerances, the system takes constant measurements and adjusts the manufacturing process to maintain the nominal geometry. This process of defining the geometry, setting the tolerances, and making adjustments are commonly referred to as geometric dimensioning and tolerancing (GD&T). Conventional chassis also require assembling in a particular order and post-assembly machining including milling, grinding, bending, and welding. The present invention allows for tighter tolerances and more accurate positioning to alleviate the need for constant adjustments, use of fixtures, and post-assembly machining. The sheet preparation techniques described in the related applications referenced above allow for precision bending of sheets of material.
In one embodiment, the above-described processes are employed to optimize self-fixturing processes. Conventional chassis fabrication systems include at least one station for fabricating parts and sections of the chassis. The precision bending techniques of the present invention allow for self-fixturing of structures, subassemblies, and the like. Conventional systems make use of part geometries for fixturing at the part-level, but such systems do not make use of such fixtures at the larger subassembly and global vehicle level. For example, fixtures make be built to position an individual part such as a tube based on known geometry. When this part is then welded to another part, however, errors in the process begin to accumulate. The methods of the present invention allow for precision bending whereby part positions can be accurately determined. Moreover, the methods of the present invention include joining methods for forming larger sub-assemblies.
Simple fasteners such as those described above and in the related applications may optionally be used to temporarily or semi-temporarily affix the sub-assemblies together until they are permanently fixed at a conventional forming station. In this manner the methods of the present invention allow for optimized self-fixturing integrated into a conventional chassis manufacturing line. For example, self-latching tabs 119 may be provided on one subassembly to secure a flange or other portion to an adjacent panel of another subassembly, as is shown in
In the alternative, the sub-assemblies may be permanently fastened and fixed in accordance with other principles and methods described such as by adhesives. Further still, the subassemblies may be initially secured by suitable means, for example, by one or several rivets. Such initial assembly allows one to leverage the tolerances and precise alignment information applied to the sheet material which would force alignment of the subassemblies with respect to one another and thus align the remaining rivet holes, and thus facilitate subsequent permanent assembly by applying the full accoutrement of rivets.
Because, the chassis architecture may be expressed in terms of panels or sides, lines, corners, and the like, information regarding the chassis may be input into the two-dimensional sheet in the flat. “In-the-flat” refers to designing the three-dimensional structure to be formed, whether the entire chassis 32 or subcomponents, and then laying out the resulting structure in a flat two-dimensional sheet. By designing in-the-flat, the features of the three-dimensional can be positioned and configured in the sheet. Because positioning structures 74 facilitate simplified, accurate bending, the information in the sheet is accurately translated into three-dimensions upon folding. In one embodiment, at least one of the geometrical features of the chassis to be formed is laid out in two-dimensional sheet.
The high precision of the above described folding and assembling technologies also allows for greater flexibility in chassis manufacture. Components, assemblies, and modules may be assembled separately and in any order because the constant measurements and adjustments are not necessary.
Although described in terms of the chassis, other members of the vehicle may be formed in accordance with the present inventions. Such members may further be integrated and joined with the chassis. For example, the chassis may be optionally provided with a seat structure.
Attention is directed to
In another exemplary embodiment of the present invention, tub module 44h is similar to the various tub modules described but includes integrated rollover protection 117 as shown in
With continued reference to
In some embodiments, the tub module may be configured to form a roll protector 117 monolithically formed with bulkhead 47h. In the illustrated embodiment, the protector is in the general shape of a headrest extending upward from bulkhead 47h. One will appreciate, however, that various shapes and geometries may be utilized. Such configuration advantageously simplifies chassis design, contributes to part reduction, and reduces the number of fabrication, joining, and other manufacturing or assembly processes. One will further appreciate that other structural components may be monolithically formed with the tub module such as steering wheel supports, A-pillars, B-pillars, C-pillars and/or other components.
The chassis of the present inventions has many advantages over conventional chassis other than those already discussed. The chassis of the present inventions also allows for easier application of multi-material and multi-architecture designs. The chassis of the present inventions allows for easy integration of several disparate processes and materials into a single, rigid structure. Thus, the chassis architecture of the present inventions may obtain the benefits of multiple chassis types. An exemplary chassis has the rigidity of a monocoque with the flexibility and weight savings of space frame.
The increased flexibility also makes low-volume production possible with complex shapes. The chassis of the present inventions makes efficient use of materials and space. The implementation of hybrid and multi-material applications enabled by the above described features can also lead to weight savings previously not obtainable with single material manufacturing techniques.
The method of manufacturing the chassis of the present inventions has several advantages. The method is less labor intensive, cheaper, makes efficient use of materials, and is faster than conventional techniques. Whereas a conventional chassis manufacturing system may require over thirty welding machines, the chassis of the present inventions may be manufactured by a few workers without complex tools. The assembly process requires little skill relative to conventional chassis manufacturing techniques. In fact, because of the use of precision bending technology, many of the processes can be automated. For example, an exemplary embodiment uses rivets extensively to fasten the chassis. The folding and joining technologies described above may be precise enough to line up the rivet holes with little or no human intervention. The use of bending techniques and simple fasteners like rivets greatly reduces manufacturing time over conventional welding of the entire chassis.
The chassis and methods of the present inventions also allow for natural three-dimensional shape generation through precision curves and geometry enabled by precision folding. Additionally, the chassis can easily be designed and manufactured with a modular architecture. The method of manufacture is enabled, in part, by the inventive design of the chassis in accordance with the present invention.
The chassis of the present inventions achieves significant savings in terms of weight and cost. The methods described above allow for significant parts consolidation and reduction of joints and components. The decreased bill of materials may also lead to higher quality than conventional designs. The chassis of the present inventions allows for consolidation of parts into a single, high-precision, rigid structure.
The chassis of the present inventions also has been found to have significant strength even without the use of large amounts of material. The uniform, joined structure provides optimized load path distribution. This translates into enhanced safety from increased energy absorption.
As will be understood from the preceding, the chassis and method of manufacture in accordance with the present inventions cover many features and processes. Chassis 32 may be formed of a variety of materials utilized and joined in myriad fashion. The method of forming individual components, parts, and assemblies may also vary in accordance with the present inventions as will the method of joining and integration into the overall chassis and vehicle. The exemplary chassis is configured for use in a conventional vehicle system, but chassis in accordance with the present invention may be configured for use in many other systems. Further, the exemplary chassis is configured for a two-door automobile, but may be modified for any vehicle family such as four-door cars, minivans, trucks, rear-wheel-drive, front-wheel-drive, and the like.
Moreover, the chassis of the present inventions may be applied in accordance with the present inventions to many other products and machines including, but not limited to, recreation vehicles, watercraft, land vehicles, motorcycles, farming equipment, construction vehicles, heavy equipment and/or machinery, military vehicles, and other structures for static and dynamic machinery and applications.
For convenience in explanation and accurate definition in the appended claims, the terms “up” or “upper”, “down” or “lower”, “inside” and “outside” and similar terms are used to describe features of the present inventions with reference to the positions of such features as displayed in the figures.
The foregoing descriptions of specific exemplary embodiments of the present inventions have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. An exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present inventions, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.
This application claims priority to U.S. Provisional Patent Application No. 61/087,147 filed Aug. 7, 2008, entitled CHASSIS AND METHODS OF FORMING THE SAME, the entire contents of which is incorporated herein for all purposes by this reference. This application claims priority to U.S. Provisional Patent Application No. 61/016,398 filed Dec. 21, 2007, entitled CHASSIS AND METHODS OF FORMING THE SAME, the entire contents of which is incorporated herein for all purposes by this reference. This application claims priority to U.S. Provisional Patent Application No. 61/087,156 filed Aug. 7, 2008, entitled METHOD FOR FORMING LAMINATE SHEET MATERIAL WITH BEND CONTROLLING STRUCTURES DEFINING A BEND LINE AND METHOD FOR FORMING THE SAME, the entire contents of which is incorporated herein for all purposes by this reference.
Number | Date | Country | |
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61016398 | Dec 2007 | US | |
61087147 | Aug 2008 | US | |
61087156 | Aug 2008 | US |