CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority benefit of U.S. Provisional Application Serial Number 62/928,217 filed 30 October 2019, the contents of which are hereby incorporated by reference.

FIELD OF THE INVENTION

[0002] The present invention in general relates to vehicle reinforcing components and in particular to vehicle reinforcing components with sections formed of different fiber reinforced composites and different geometries.

BACKGROUND OF THE INVENTION

[0003] Weight savings in the automotive, transportation, aerospace, and logistics based industries has been a major focus in order to make more fuel-efficient vehicles both for ground and air transport. In order to achieve these weight savings, light weight composite materials have been introduced to take the place of metal structural and surface body components and panels. Composite materials are materials made from two or more constituent materials with significantly different physical or chemical properties, that when combined, produce a material with characteristics different from the individual components. The individual components remain separate and distinct within the finished structure. A composite material may be preferred for reasons that include materials which are stronger, lighter, or less expensive when compared to traditional materials. Still another advantage over metals is reduced corrosion, leading to longer operational life and reduced maintenance costs. [0004] There are two categories of constituent materials: matrix and reinforcement. At least one portion of each type is required. The matrix material surrounds and supports the reinforcement materials by maintaining their relative positions. The reinforcements impart their special mechanical and physical properties to enhance the matrix properties. A synergism produces material properties unavailable from the individual constituent materials, while the wide variety of matrix and strengthening materials allows the designer of the product or structure to choose an optimum combination.

[0005] The use of fiber inclusions to strengthen a matrix is well known to the art. Well established mechanisms for the strengthening of a matrix include slowing and elongating the path of crack propagation through the matrix, as well as energy distribution associated with pulling a fiber free from the surrounding matrix material. In the context of sheet molding composition (SMC) formulations, bulk molding composition (BMC) formulations, and resin transfer molding (RTM) fiber strengthening has traditionally involved usage of chopped glass fibers.

[0006] Vehicle reinforcing components are designed to protect vehicle occupants during collisions by absorbing and dissipating kinetic energy. For example, as shown in FIG. 1, front passenger vehicle doors 12 and back passenger vehicle doors 14 commonly include side impact bars 16 and 18, respectively, also known as an anti-intrusion bars or beams, which are designed to protect passengers from side impacts. Side impacts are particularly dangerous since the location of impact is quite close to the passenger, who can be immediately compressed by the impacting vehicle or object. The role of the side impact bar is to absorb the kinetic energy of the colliding vehicles or objects that is partially converted into internal work of the members involved in the crash. Vehicle reinforcing components are also designed to minimize damage to the vehicle in low speed collisions by absorbing the kinetic energy by temporally deforming or deflecting. [0007] Thus, there exists a need for a vehicle reinforcing component construction that utilizes composite materials to lower the weight of the component, while improving the safety performance and manufacturability compared to conventional vehicle components.

SUMMARY OF THE INVENTION

[0008] A shock absorption part is provided that includes a beam having a first end and an oppositely opposed second end and a central region therebetween. The beam is formed of a first layer extending from the first end of the beam to the second end of the beam and a second composite layer overlaying the first layer in the central region of the beam. The second composite layer has a cross section that is tapered towards the first end and the second end of the beam.

[0009] A vehicle component is provided that includes a body having a first fixture region and a second fixture region, and the beam as described above. The first end of the beam is attached to the first fixture region of the body and the second end of the beam is attached to the second fixture region of the body.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention is further detailed with respect to the following drawings that are intended to show certain aspects of the present invention but should not be construed as a limit on the practice of the present invention.

[0011] FIG. 1 shows prior art driver and rear vehicle door assemblies showing side impact bars within the door structures;

[0012] FIG. 2A shows a cross sectional view of a shock absorption part according to embodiments of the present invention; [0013] FIGS. 2B and 2C show different forms of a second layer of a shock absorption part according to embodiments of the present invention;

[0014] FIG. 3A shows a side view of a vehicle body component according to embodiments of the present invention;

[0015] FIG. 3B shows a cross-sectional view of the vehicle body component construct according to embodiments of the present invention;

[0016] FIG. 3C shows a side view of a vehicle body component according to embodiments of the present invention;

[0017] FIG. 4 shows an expanded perspective view of a vehicle body component assembly according to embodiments of the present invention;

[0018] FIG. 5 shows an expanded perspective view of a vehicle body component assembly according to embodiments of the present invention;

[0019] FIG. 6 shows a perspective view of a vehicle body component assembly attached to a vehicle frame according to embodiments of the present invention;

[0020] FIG. 7 is a graph showing a pattern of beam thickness for a shock absorption part according to embodiments of the present invention; and

[0021] FIG. 8 is a graph showing pole intrusion for a given force for a shock absorption part according to embodiments of the present invention compared to a prior art component.

DESCRIPTION OF THE INVENTION

[0022] The present invention has utility as a lightweight vehicle reinforcing component providing improved automotive crash resistance by strengthening vehicle structural and/or body components while reducing weight. Accordingly, vehicle reinforcing components according to embodiments of the present disclosure have improved safety performance and manufacturability and reduced weight compared to existing vehicle reinforcement components. While the present invention is discussed in the context of vehicle door due the rigorous safety standards associated with vehicle doors, it is appreciated that the present invention is suited for the reinforcement of a variety of vehicle components that also illustratively include hoods, decklids, roofs, tailgates, liftgates, bumpers, fenders, quarter panels, engine compartments, and the like.

[0023] The present invention will now be described with reference to the following embodiments. As is apparent by these descriptions, this invention can be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. For example, features illustrated with respect to one embodiment can be incorporated into other embodiments, and features illustrated with respect to a particular embodiment may be deleted from the embodiment. In addition, numerous variations and additions to the embodiments suggested herein will be apparent to those skilled in the art in light of the instant disclosure, which do not depart from the instant invention. Hence, the following specification is intended to illustrate some particular embodiments of the invention, and not to exhaustively specify all permutations, combinations, and variations thereof.

[0024] It is to be understood that in instances where a range of values are provided that the range is intended to encompass not only the end point values of the range but also intermediate values of the range as explicitly being included within the range and varying by the last significant figure of the range. By way of example, a recited range of from 1 to 4 is intended to include 1-2, 1-3, 2-4, 3-4, and 1-4.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0026] Unless indicated otherwise, explicitly or by context, the following terms are used herein as set forth below.

[0027] As used in the description of the invention and the appended claims, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0028] Also as used herein, “and/or” refers to and encompasses any and all possible combinations of one or more of the associated listed items, as well as the lack of combinations when interpreted in the alternative (“or”).

[0029] As used herein, the term “side impact pole test” refers to NCAP Side Impact Rigid Pole Test as defined by U.S. Department of Transportation Rev. 9/19/12.

[0030] As used herein, the term “continuous fiber” refers to fibers that extend from edge to edge of a vehicle component, or fibers that are placed in a pattern within the vehicle component without having been cut.

[0031] FIGS. 2A-2C show embodiments of vehicle reinforcements according to embodiments of the present invention. According to embodiments, the vehicle reinforcement is a beam 20 that has a first end 21 and a second end 22. The beam 20 has a central region 23 positioned between the first end 21 and the second end 22. The beam 20 is formed of a first layer 24 and a second composite layer 25. According to embodiments, the beam 20 is configured to be an engine bolster, a bumper, or an anti-intrusion bar. The first layer 24 extends from the first end 21 of the beam 20 to the second end 22 of the beam 20. The second composite layer 25 overlays the first layer 24 in the central region 23 of the beam 20. As best shown in FIG. 2A, the second composite layer 25 is positioned on a single side of the first layer 24, and the second composite layer 25 has a cross section that is tapered towards the first end 21 and the second end 22 of the beam 20.

[0032] FIG. 7 shows a graph of the pattern of thickness of a beam 20 having a first layer 24 and a second layer 25 according to embodiments of the present disclosure. As shown in FIG. 7, the second composite layer 25 has an increased thickness at the center of the beam and according to embodiments has a decreased thickness at the first end 21 and second end 22 of the beam.

[0033] The second composite layer in some inventive embodiments is preferably formed by press-molding a material that has been laminated in a stepwise shape in advance. Compared to the invention described in US 11/905785, which is manufactured by peeling system after the molding, press-molding process can reduce waste generation.

[0034] According to embodiments, the first layer 24 is formed from steel, aluminum, resin, or a combination thereof. The first layer 24 is reinforced with one of carbon fiber or glass fiber [0035] According to embodiments, the reinforcing carbon fibers or glass fibers of the first layer 24 are preferably unidirectional. The first layer 24 has a generally constant thickness over the length of the beam 20, which according to some inventive embodiments is between 1 and 10 mm.

[0036] According to other inventive embodiments, the second composite layer 25 is made up of a plurality of layers of reinforcing fibers 27, which according to embodiments includes between 2 and 30 layers of reinforcing fibers. According to embodiments, the layers of reinforcing fibers 27 are made of preferably carbon fibers. The layers of reinforcing fibers 27 are built up from the first layer 24 with the longest layer of reinforcing fibers 27 being positioned on the first layer 24 followed by shorter and shorter layers of reinforcing fiber 27. The layers of reinforcing fibers 27 are stacked onto one another in a stepwise fashion, thereby providing the cross section of the second composite layers 25 that tapers towards the first end 21 and second end 22 of the beam 20. According to embodiments, given the position of the second composite layer over the central region 23 of the beam 20, according to embodiments, the second composite layer 25 has a thickness that is greatest near the center of the beam 20. According to other embodiments, the second composite layer 25 has a thickness that is greatest at a location other than at the center of the beam 20. According to embodiments, the fibers that make up the layers of reinforcing fibers 27 are unidirectional. Unidirectional fibers exhibit high tensile strength and relatively low compressive strength. Therefore, the second composite layer is tapered toward the opposite side of the impacted side. More specifically, the second composite layer is tapered toward the inside of the door. In other words, the impact is received from the first composite layer side. In this case, a tensile force is applied to the top of the tapered second composite, and a compression force is applied to the base side. According to embodiments, the second composite layer 25 is tapered along the direction of the unidirectional fibers that make up the layers of reinforcing fibers 27. Alternatively, each of the plurality of layers of reinforcing fibers 27 is angularly offset from the preceding layer of layers of reinforcing layers 27. Offsetting the orientation of the various layers enables strength in multiple directions. The orientation of each subsequent layers of reinforcing fibers 27 may be offset from that of the preceding layer of reinforcing fibers 27 by an angular displacement a relative to the principal orientation of the first layer, for example the X axis. The layers can be overlaid with a variety of angular displacements relative to a first layer. If zero degrees is defined as the long axis X of the first layer of reinforcing fibers, the subsequent layers are overlaid at angles of 0-90°. For example, the angular displacement a may be 45° resulting in a 0-45-90-45-0 pattern of reinforcing fiber layers 27. Further specific patterns illustratively include 0-45-90-45-0, 0-45-60-60-45-0, 0-0-45-60-45-0-0, 0-15-30-45-60-45-30-15-0, and 0- 90-45-45-60-60-45-45-90-0. According to embodiments, the angular displacement of the layers of reinforcing fibers 27 is 0, making the fibers of layers 27 unidirectional along the long axis of the beam 20. While these exemplary patterns are for from 5 to 10 layers of unidirectional fibers, it is appreciated that the layers of reinforcing material may include from 2 to 100 layers, more preferably 10 to 40 layers, and even more preferably, 20 to 30 layers. According to embodiments, the thickness of each layer 27 of the second composite layer 25 is preferably 0.1 mm to 1.0mm, and more preferably 0.2mm to 0.5mm.

[0037] According to embodiments the beam 20 includes a third layer 26 that overlays the first layer 24 on a side opposite to the second composite layer 25. The third layer 26 is formed of a composite material, steel, aluminum, or a combination thereof. Embodiments in which the third layer 26 is formed of a composite material are formed of SMC, epoxy, acrylonitrile butadiene styrene (ABS), polycarbonate, or thermoplastic resin reinforced with one of carbon fibers or glass fibers, which according to embodiments are unidirectional fibers. According to embodiments, the unidirectional fibers of the third layer 26 are arranged in a direction that is the same as a direction of unidirectional fibers in the second composite layer 25, which for example is along the longitudinal axis of the beam 20. According to embodiments, the third layer 26 is laminated to the first layer 24 on the side opposite to the second composite layer 25. According to embodiments, the third layer 26 extends from the first end 21 of the beam 20 to the second end 22 of the beam 20.

[0038] According to embodiments, as best shown in FIG. 3A, the vehicle reinforcement beam 20 is configured for use as an anti-intrusion bar in a vehicle component 30. According to embodiments, a vehicle component 30 of the present invention includes a body 32 having a first fixture region 34 and a second fixture region 36, and a beam 20 as described above. According to embodiments, the vehicle construct 30 may also include a second beam 38, which according to embodiments is formed as described with regard to the first beam 20 or formed of a carbon fiber reinforced sheet molding compound material. The body 32 and beams 38, 20 each have a predetermined geometry based on a given application and intended location within a vehicle so as to be complementary to other components of the vehicle. It is appreciated that the first fixture region 34 and a second fixture region 36 are formed integral from the same material as the body 32, or alternatively are each independently inserts to the body having a different composition from the remainder of the body 32.

[0039] The body 32 is limited in construction and materials only by compatibility with the beam 20 or beams 20, 38, and is illustratively formed of steel, aluminum, magnesium alloys, titanium, titanium alloys, fiberglass set up sheets embedded in thermoset resin, SMC, BMC, or a combination thereof. In certain inventive embodiments, the body 32, the first fixture region 34, and the second fixture region 36 are formed of SMC and other materials. The body 32 has an inner side and an outer side relative to vehicle passenger compartment. In still other embodiments, the first fixture region 34, and the second fixture region 36 are integral with the body 32. It is noted that joints are conventionally formed based on the nature of the material with adhesives, mechanical fasteners, or a combination thereof genetically, while welding and brazing are most often used to form a body 32 from metals. The beam 20, and according to embodiments the second beam 38, is joined to the body between the second fixture region 34 and the first fixture region 36 using a combination of mechanical fasteners and adhesive. It is further appreciated that the body 32 includes hardened points for mounting hinges 42, in FIG. 6 on a front stile and a rear stile lock (not shown for visual clarity) to selectively allow the component 30 to secure to the remainder of the vehicle. While it is conventional that a component 30 that forms a vehicle door has two front hinges and a lock-vehicle chassis post engagement to form a three point closure, it should be appreciated that this is only exemplary and other types of components 30 and indeed, other types of doors have different hardware for selectively moving the component relative to the vehicle.

[0040] The first beam 20 is attached to the body 32, generally at the first fixture region 34 and second fixture region 36, such that first beam 20 spans between the first fixture region 34 and second fixture region 36 of the body 32. As noted above, the first beam 20 is formed of a plurality of fiber reinforced layers, with the majority of fiber direction chosen to be orthogonal to an expected direction of impact. It is appreciated that lesser amounts of the total fiber content in the first beam 20 can have a different orientation relative the majority of the fiber direction. According to embodiments and as shown in FIG. 3B, the second composite layer 25 of the beam 20 is positioned between the first layer 24 of the beam 20 and an interior side 66 of the body 32 of the vehicle component 30. Accordingly, in FIGS. 3A and 3B, the second composite layer 25 of the beam 20 is visible on the interior side 66 of the body 32.

[0041] In some inventive embodiments, the first beam 20 is formed with a “top hat” or corrugated plate shape characterized by edges parallel to a central section with orthogonal sides intermediate between the edges and the central section. In still other embodiments, the beam 20 is formed with a rectilinear box cross section. It is appreciated that the first beam 20 is formed with still other cross-sectional shapes, as measured in the middle of the beam 20; these other cross-sectional shapes including triangular, pentagonal, and hexagonal. According to some inventive embodiments, the first beam 20 has surface treatments 43 illustratively including grooves, ridges, dimples, or a combination thereof that are known to contribute additional strength thereto.

[0042] According to embodiments, the vehicle component includes a second beam 38. The second beam 38 is attached to the body 32, generally at the first fixture region 34 and second fixture region 36, such that the second beam 38 spans between the first fixture region 34 and the second fixture region 36 of the body 32. According to embodiments, the second beam 38 is formed from chopped fiber reinforced resin and is characterized by a complex shape positioned such that to the extent there is concavity, the opening is directed away from the expected direction of impact. The second beam 38 is formed from a variety of resins. These illustratively include SMC, epoxy, acrylonitrile butadiene styrene (ABS), polycarbonate, or random-oriented fiber reinforced thermoplastic resin (FRTP). When an inventive component 30 is a door, the expected direction of impact is from the door exterior. Fiber fillers operative herein illustratively include carbon fibers, glass fibers, aramid fibers, cellulosic fibers, or a combination thereof. In some inventive embodiments, the chopped fiber is glass fiber, alone or in combination with other types of fiber. It is appreciated that in some inventive embodiments, a minority by fiber weight in the second beam 38 is continuous fiber. A typical thickness of the second beam 38 at a given point ranges from 0.5 to 6 mm when the second beam is carbon fiber-SMC(CF-SMC). In still other embodiments, the thickness of the second beam 38 is from 1.5 to 5 mm when the first beam is CF-SMC.

[0043] In some inventive embodiments, the second beam 38 is located inwardly relative to an outer surface of the first beam, which is relative to the first layer 24 and/or the third layer 26. Accordingly, in an impact event, the beam 20 contacts an impacting object before second beam 38. Therefore, impact absorption is mainly performed by the beam 20. It is appreciated that the second beam 38 is readily formed from uniform thickness resin molding or can vary in thickness across the extent thereof. According to some inventive embodiments, the second beam 38 has surface treatments 41 illustratively includes grooves, ridges, dimples, or a combination thereof that are known to contribute additional strength thereto.

[0044] While the first beam 20 is shown mounted to the body 32 near a lower edge of the body 32 and the optional second beam 38 is shown mounted above and spaced apart from the first beam 20 in the drawings, it is appreciated that the relative position of the beams 20, 38 is varied depending on the nature of the vehicle component 30. For example, the beam 20 is positioned near the center of the vehicle component 30. In still other embodiments, additional beams formed of the materials of the first beam 20 or the second beam 38 are present to impart desired properties to a given vehicle component 30. It is also appreciated that while the first beam 20 and second beam 38 are shown generally parallel to one another to provide excellent response to a side pole crash test, beams according to the present invention are readily deployed at a variety of relative angles.

[0045] As best shown in FIG. 6, according to certain inventive embodiments, the first fixture region 34 defining a front stile of the door is configured to receive at least one hinge 42 to secure the vehicle component 30 to a frame of a vehicle 50, while the second fixture region 36 defining the rear stile of the door is configured to receive a latch 44 to releasably secure the vehicle component 30 to the vehicle frame 50. According to some inventive embodiments, such as those shown in FIGS. 3A and 3C, the vehicle component 30 includes a reinforcing component 46, 48, 301. As shown in FIG. 3 A, the vehicle component includes one or both of a first reinforcing component 46 attached to the body 32 at the first fixture region 34 and a second reinforcing component 48 attached to the body 32 at the second fixture region 36. As shown in FIG. 3C, the vehicle component 30 includes a reinforcing component 301. According to embodiments, the first reinforcing component 46 and second reinforcing component 48 are joined such that they are two ends of a single reinforcing component. According to embodiments the reinforcing components 46, 48, 301 are formed for carbon fiber reinforced sheet molding compound. As shown in FIG. 3C, the reinforcing component 301 and the beam 20 are attached to the body 32 with a plurality of fasteners 302. In an impact, the place connected to the fastener has the strongest strength and becomes weaker as it moves away from the fastener. Since the central part is farthest from the fastener, the strength is weakest. For this reason, the central part of the beam 20 is reinforced with the second layer 25. To further enhance the strength of the beam near the fasteners when the first layer 24 is a composite material, embodiments of the first layer 24 include metal mounting reinforcements embedded in the composite material forming the first layer 24. According to embodiments, the metal reinforcements are steel [0046] As shown in FIGS. 4 and 5, the vehicle component 30 may be an inner structure for reinforcing a vehicle door or other vehicle body component. According to embodiments, the vehicle component 30 is connected to an outer skin 60 on an outer side 62 of the body 32. In further embodiments, the vehicle component 30 is placed between an outer skin 60 on an outer side 62 of the body 32 and an inner skin 64 on an inner side 66 of the body 32.

[0047] According to embodiments, the outer skin 60 is an outer body panel formed of at least one of steel, aluminum, and a composite material. The first layer 24 is reinforced with one of carbon fiber or glass fiber. According to embodiments, the outer skin 60 is suitable as Class A surface with a high gloss surface finish. As used herein, the term “high gloss surface” refers to a surface having minimal perceptible surface defects when visually inspected with an unaided normal human eye for about three seconds from about 24-28 inches from the viewer and normal to the part surface +/- 90 degrees in a well-lit area. That is, the term “high gloss surface” refers to a surface capable of being painted and accepted as a “Class A” autobody part. This is commonly measured by ASTM D523. In the automotive industry, a Class A surface is a surface a consumer can see without opening the vehicle (e.g., opening the hood or decklid), while a Class A surface finish generally refers to painted outer panels and specifically to the distinctness of image (DOI) and gloss level on the part. It is appreciated that a surface layer may be subjected to sanding, trimming, and priming prior to receiving a paint coating that imparts high gloss, yet must retain dimensionality and adhesion uniformity to primer and paint so as to achieve a high gloss finish.

[0048] The inner skin 64 is an aesthetic panel facing the vehicle interior. According to embodiments, the vehicle component 30 further comprising at least one of sound deadening material, vehicle electronics, an aramid panel, and HVAC components positioned in a cavity defined between the body 32 and at least one of the outer skin 60 and the inner skin 64. [0049] The present invention is further detailed with respect to the following non-limiting examples.

Example 1

[0050] A vehicle door is constructed according to FIGS. 3A-5 with a glass fiber reinforced sheet molding compound (SMC) body 32, a beam 20 as described above, a carbon fiber reinforced SMC second bean 38, and a carbon fiber reinforced SMC reinforcing component 46, 48. The second composite layer 24 of the beam 20 has a thickness per layers 27 of 0.3 mm and includes 12 layers 27. The first layer 24 is formed of six layers of unidirectional glass fiber material having a width of 180 mm and a thickness of 0.3 mm per layer. The third layer 26 is formed of two layers of unidirectional carbon fiber material having a width of 180 mm and a thickness of 0.3 mm per layer. The layers are laminated together. The beam 20 has a length of 1160 mm in the fiber direction, which is the direction of the longitudinal axis. The beam 20 is formed into a double “top hat” shape. The reinforcing part 301 and second bean 38 are formed of carbon fiber reinforced SMC. The resulting door represents a 25% weight savings relative to a similar door with steel beams and reinforcing components. The inventive door passes the pole intrusion test and provides reduced pole intrusion compared to a similar door with steel beams and reinforcing components, as demonstrated in the graph of FIG. 8 and Table 1.

Table 1 Example 2

[0051] The test is performed in the same manner as in Example 1 except for the following conditions. The second layer 25 is formed of 16 layers of unidirectional carbon fibers. The first layer 24 is formed of 12 layers of glass fiber material and the third layer 26 is formed of 2 layers of carbon fiber material. The beam 20 is shaped into a single “top hat” shape. Reinforcement 301 and a second beam 38 are formed of steel. The results of Example 2 are shown in Table 2.

Example 3

A comparative example test is performed in the same manner as in Example 1 except that the first beam 20, the second beam 38, and the Reinforcement 301 are formed of steel. The results of Example 3 are listed in Table 2 in comparison with the results of Example 1 and Example

2.

Table 2

[0052] The foregoing description is illustrative of particular embodiments of the invention but is not meant to be a limitation upon the practice thereof. The following claims, including all equivalents thereof, are intended to define the scope of the invention.