Bumper assembly

A bumper assembly includes a bumper beam elongated in a cross-vehicle direction and a bumper that is plastic. The bumper is elongated in the cross-vehicle direction and is affixed to the bumper beam. The bumper beam is rigid relative to the bumper. The bumper defines a cavity enclosed by the bumper. The cavity is elongated in the cross-vehicle direction.

BACKGROUND

The Global Technology Regulation (GTR) and the New Car Assessment Program (NCAP) specify leg-injury criteria for pedestrian protection. The regulations are aimed at reducing the impact force to the legs of a pedestrian by a vehicle bumper during a vehicle-pedestrian impact.

Some vehicles, such as light duty trucks and sport utility vehicles (SUVs), for example, may have a bumper height that could lead to an uneven impact on the femur and/or tibia of the pedestrian by the vehicle bumper during the vehicle-pedestrian impact. For example, light duty trucks may have bumper heights to provide ground clearance to clear speed bumps, curbs, parking blocks, inclined driveway ramps, hills, rough roads, etc. Some vehicles with such bumper heights also have off-road capabilities that preclude having any components below the bumper. As such, there is an opportunity to design a vehicle front-end for pedestrian leg impact energy management while addressing ground clearance requirements.

DETAILED DESCRIPTION

A bumper assembly includes a bumper beam elongated in a cross-vehicle direction and a bumper that is plastic. The bumper is elongated in the cross-vehicle direction and affixed to the bumper beam. The bumper beam is rigid relative to the bumper. The bumper defines a cavity enclosed by the bumper. The cavity is elongated in the cross-vehicle direction.

The bumper may include an air intake elongated in the cross-vehicle direction. The bumper may include an upper beam above the air intake and a lower beam below the air intake. The cavity may be defined by the lower beam and the upper beam. The upper beam and the lower beam may be monolithic. The bumper may include lamp compartments between the upper beam and the lower beam.

The bumper may include lamp compartments above the cavity. The bumper may include an upper beam above the lamp compartments and a lower beam below the lamp compartments.

The bumper may include an upper beam and a lower beam spaced from the upper beam. The lower beam may define the cavity. The bumper beam may abut the upper beam and the lower beam. The bumper beam may abut the upper beam and a skid plate may abut the lower beam. The lower beam has an upper end and a lower end and increases in thickness in a vehicle-rearward direction toward the lower end. The cavity may increase in thickness in the vehicle-rearward direction toward the lower end of the lower beam.

The bumper may have a lower end and the cavity may increase in thickness to the lower end. At least a portion of the cavity at the lower end may be greater than 30 mm in a vehicle-rearward direction.

A skid plate may abut the bumper below the bumper beam and may ex from the bumper in a vehicle-rearward direction.

The bumper may have a class-A surface.

The bumper beam may be metal.

The bumper may have a reference height less than 500 mm.

The cavity may be aligned with a knee of a pedestrian impact test leg form.

The cavity may be aligned with a knee of a flex-PLI leg form.

The bumper may be blow molded.

With reference to the Figures, wherein like numerals indicate like parts throughout the several views, a bumper assembly10of a vehicle12includes a bumper beam14elongated in a cross-vehicle direction CV and a bumper16that is plastic. The bumper16is elongated in the cross-vehicle direction CV and is affixed to the bumper beam14. The bumper beam14is rigid relative to the bumper16. The bumper16defines a cavity18enclosed by the bumper beam14. The cavity18is elongated in the cross-vehicle direction CV.

During an impact with a leg of a pedestrian, the cavity18collapses to absorb energy. For example, with reference toFIG. 8, the bumper16may impact the knee20of a pedestrian impact test leg form22. The leg form22may be a flexible pedestrian leg impactor (Flex-PLI) leg form. Example regulations that can use the leg form22include Global Technical Regulation (GTR), ECE R127, and Korean Motor Vehicle12Safety Standards (KMVSS). Example new car assessment programs that can use the leg form22include EuroNCAP, CNCAP, and ANCAP.

The vehicle12may be any suitable type of automobile, e.g., a passenger or commercial automobile such as a sedan, a coupe, a truck, a sport utility vehicle, a crossover vehicle, a van, a minivan, a taxi, a bus, etc.

The vehicle12includes a vehicle frame24and a vehicle body26. The vehicle body26and the vehicle frame24may have a body-on-frame construction (also referred to as a cab-on-frame construction) in which the body26and frame24are separate components, i.e., are modular, and the body26is supported on and affixed to the frame24. The example shown in the Figures (for exampleFIG. 5) is a body-on-frame construction. As another example, the vehicle body26and the vehicle frame24may be of a unibody construction in which the vehicle frame24is unitary with a vehicle body26(including frame rails, pillars, roof rails, etc.). Alternatively, the frame24and body26may have any suitable construction. The frame24and body26may be of any suitable material, for example, steel, aluminum, and/or fiber-reinforced plastic, etc.

The vehicle12has a front-end structure28. The front-end structure28includes a grille assembly30, the bumper assembly10, and a skid plate32. One or more components of the front-end structure28may include components of the vehicle body26and/or the vehicle frame24, as described further below. The grille assembly30is above the bumper assembly10. The bumper assembly10is above the skid plate32and vehicle-forward of the skid plate32

The grille assembly30may be a component of the body26and may be supported on other components of the body26. For example, the vehicle body26may include two rails34. The rails34may support fenders (not numbered) of the vehicle body26. The rails34may be referred to as fender support rails and/or shotgun rails. The rails34are spaced from each other along the cross-vehicle direction CV. The rails34may each extend from the vehicle frame24to an A-pillar of the vehicle body26. The rails34may be supported on the vehicle frame24, in which case the rails34support the grille assembly30on the vehicle frame24. As one example, each rail34may be fixed directly to the vehicle frame24with no intermediate component, e.g., by fasteners, welding, etc.

The grille assembly30may include a grille reinforcement36and a grille38. The grille reinforcement36supports the grille38on the vehicle body26, e.g., on the rails34. The grille reinforcement36may be attached to the rails34in any suitable way, e.g., fasteners, welding, etc. The grille38may be supported by the grille reinforcement36. The grille38may be fixed relative to the grille reinforcement36. In other words, the grille38and the grille reinforcement36move together as a unit.

The grille reinforcement36may be elongated along the cross-vehicle direction CV. The grille38may extend over, i.e., may cover, the grille reinforcement36. The grille reinforcement36reinforces the grille38to distribute the load across a leg form22during a pedestrian impact test, as shown inFIG. 8, and as described further below. Specifically, the grille reinforcement36and bumper16are positioned relative to each other to distribute loading of force across the leg form22, i.e., so both the grille reinforcement36and the bumper16impact the leg form22and reduce relative movement between the femur and the tibia.

The grille reinforcement36includes the two brackets40. Each bracket40is disposed between the rails34and the grille38. The grille38is in a vehicle-forward direction F of the brackets40. The two brackets40are spaced from each other along the cross-vehicle direction CV.

Each bracket40has two legs42. Both legs42extend from the respective rail34toward the grille38. In other words, each leg42is attached to the respective rail34and extends in the vehicle-forward direction F toward the grille38. As one example, as shown in the Figures, each bracket40may be spaced from the grille38, e.g., by bars44. As another example, each leg may extend to the grille38, i.e., be in contact with the grille38. The legs42are attached to the respective rail in any suitable way, e.g., fasteners, welding, etc.

As set forth above, the grille reinforcement36includes at least one bar44. In the example shown in the Figures, the grille reinforcement36includes the two bars44. The grille reinforcement36may include additional bars44(not shown) in addition to the two bars44and which have the same structure and perform the same function as the bars44shown in the Figures. In examples including more than one bar44, the bars44are spaced from each other, i.e., vertically spaced from each other. The spacing between the two bars44and the vertical position of the bars44may be designed based on the vehicle12ride-height to align with the desired part of the leg form22. In examples including more than one bar, the bars44may be parallel to each other.

The bars44may be aligned with each other along the vehicle12longitudinal axis L. In other words, the bars44may be in the same vertical plane. As another example, the bars44may be offset from each other along the vehicle12longitudinal axis L.

The bars44are elongated along the cross-vehicle direction CV from one of the brackets40to the other of the brackets40. The bars44may extend outboard beyond the brackets40. In another example, the bars44may terminate at the brackets40.

The two bars44may be attached to both of the brackets40. The bars44may be fixed to the brackets40in any suitable way including fasteners, welding, etc.

With reference to the Figures, the bars44may vary in size and in material. The bars44may be of any suitable material including steel, aluminum, etc. The bars44may, for example, be hollow. As another example, the bars44may have a reinforcement inside the bars44. As another example, the bars44may be solid (not shown). The bars44may be different from each other in shape.

The grille38may be elongated along a cross-vehicle direction CV. The grille38may elongated from one of the rails34to the other of the rails34. The grille38is in the vehicle-forward direction F of the rails34.

The grille38includes a vehicle-forward face46. The vehicle-forward face46faces the vehicle-forward direction F. The vehicle-forward face46may be a class-A surface, i.e., a surface specifically manufactured to have a high-quality, finished aesthetic appearance free of blemishes. The grille38may be of any suitable material, including plastic, such as injection-molded plastic; metal, such as aluminum or steel; or any other suitable material.

The vehicle-forward face46of the grille38may cover the bars44in the vehicle-forward direction F, as shown in the Figures. In other words, in such an example, the bars44are not visible from an exterior of the vehicle12. As another example, the bars44may extend through the grille38such that the vehicle-forward faces46of the bars44are visible from an exterior of the vehicle12. In such an example, both the vehicle-forward face46of the grille38and the vehicle-forward faces46may each be a class-A surface, i.e., a surface specifically manufactured to have a high-quality, finished aesthetic appearance free of blemishes. In the example where the bars44extend through the grille38, the vehicle-forward faces46of the bars44may be flush with the vehicle-forward face46of the grille38, or the vehicle-forward faces46of the bars44may be in the vehicle-forward direction of the vehicle-forward face46of the grille38.

The grille38may include cavities for receiving the bars44. In other words, the cavities are sized to receive the bars44. In one embodiment, the grille38is over-molded to the grille reinforcement36. “Over-molded” is a structural description of the grille38, not the process by which the grille38is made. In other words, the over-molded grille38has the structure of an over-molded component. When over-molded, the grille38may be a single, uniform piece of material with no seams, joints, and may be fixed to the bars44without fasteners or adhesives holding the grille38and the bars44together. In such an example, the grille38has a shape that conforms to a mold, e.g., an injection mold, used to form the grille38as an over-molded component to the bars44. In other examples, the grille reinforcement36is fixed to the grille38with fasteners, adhesive, etc.

The grille reinforcement36, i.e., both bars44and both brackets40, is rigid relative to the leg form22of a pedestrian impact test. In other words, during the pedestrian protection impact test, the bars44and the brackets40experience minimal deformation upon impact with the leg form22.

As set forth above, the front-end structure28includes the bumper assembly10. The bumper assembly10includes the bumper beam14and the bumper16supported on the bumper beam14. The bumper16may be attached to the vehicle frame24. As an example, the bumper16may be fixed directly to the vehicle frame24and by any suitable way including fasteners, welding, etc. The bumper beam14is rigid relative to the bumper16, e.g., the bumper16deforms more than the bumper beam14during impact with the leg form22. The bumper beam14may be of any suitable material such as metal (steel, aluminum, etc.), fiber-reinforced plastic, etc. The bumper16is affixed to the bumper beam14in any suitable manner, e.g., fasteners.

The bumper16is elongated along the cross-vehicle direction CV. The bumper16has a vehicle-forward face48. The vehicle-forward face48may be a class-A surface, i.e., a surface specifically manufactured to have a high-quality, finished aesthetic appearance free of blemishes.

The bumper16is plastic. The bumper16may be blow molded. “Blow-molded” is a structural description of the bumper16, not the process by which the bumper16is made. In other words, the blow-molded bumper16has the structure of a blow-molded component. When blow-molded, the bumper16may be monolithic (i.e., a single, uniform piece of material with no seams, joints, etc.) with the cavity18enclosed by the plastic of the bumper16. The blow-molded bumper16has a shape that conforms to a mold and the shape includes the class-A surface, as described above.

With reference toFIGS. 5 and 8, the bumper assembly10is below the bars44Specifically, the bumper16is below the bars44. The bumper16may be substantially aligned with the bars44along the vehicle12-longitudinal axis L. Specifically, and as shown inFIG. 8, the bars44have a vehicle-forward face46, and the vehicle-forward face46of the bars44and the vehicle-forward face46of the bumper16may be aligned along the vehicle12-longitudinal axis L. As an example, the vehicle-forward face46of the bumper16and the vehicle-forward faces46of the bars44may be aligned along the vehicle12-longitudinal axis L within +/−15 millimeters. Accordingly, the vehicle-forward face46of the bumper16and the vehicle-forward faces46of the bars44may simultaneously engage a leg form22, as shown inFIG. 8, to distribute loading of force across the leg form22and reduce relative movement between the femur and the tibia.

The bumper16includes a lower beam50, an upper beam52, and sides54connecting the lower beam50and the upper beam52. The sides54are spaced from each other on opposite sides54of the vehicle12. The lower beam50and the upper beam52may extend from one side54to the other side54. The lower beam50may include a spine56extending continuously from one side54to the other side54and one or more lobes58extending downwardly from the spine. In the example shown in the Figures, the lower beam50includes three lobes58. The cavity18extends through the spine56and all three lobes58in the example shown in the Figures. The bumper beam14abuts the upper beam52and the lower beam50, as shown inFIGS. 3 and 4.

The bumper16defines a cavity18enclosed by the bumper16. In other words, the plastic of the bumper16prevents substantially all fluid communication between the cavity18and the external atmosphere. Specifically, minimal communication may exist between the cavity18and the external atmosphere as small water drain holes, manufacturing artifacts such as locating holes, pin retraction holes, etc.

The cavity18is elongated in the cross-vehicle direction CV. Specifically, the cavity18may extend from one side54to the other side54through the lower beam50. The cavity18may also extend from one side54to the other side54through the upper beam52. The cavity18may extend continuously through the lower beam50, both sides54, and the upper beam52in a loop, i.e., a continuous circuit. In such an example, the cavity18may be formed by blow-molding.

The lower beam50has an upper end60at the spine56and a lower end62spaced from the spine56. The lower beam50terminates at the lower end62, i.e., the lower end62is a terminal end. The cavity18may increase in thickness in a vehicle-rearward direction R from the upper end60toward the lower end62. The thickest region of the lower beam50may be at the lower end62. The thickest portion of the cavity18may be at the lower end. At least a portion of the cavity18is greater than 30 mm in a vehicle-rearward direction R. For example, the cavity18may be greater than 30 mm at the lower end62. In such an example, the cavity18may be the thickest at the lower end62.

The cavity18is aligned with a knee20of a pedestrian impact test leg form22. Specifically, the cavity18may be aligned with a knee20of a flex-PLI leg form22. As described above, the bumper16collapses at the cavity18during impact with the knee20. The region of the cavity18vertically aligned with the knee20may be greater than 30 mm in a vehicle-rearward direction R. The thickest region of the cavity18may be aligned with the knee20.

The bumper16has a reference height less than 500 mm. As is known, the reference height is determined by moving a panel positioned 25 degrees from horizontal toward the bumper16. The first point of the bumper16to touch the panel is the bumper16reference height.

In operation during a pedestrian protection test, the bumper16and the grille38contact the leg form22substantially simultaneously. The grille reinforcement36reinforces the grille38. The bumper16impacts the leg form22at the knee20and the bars44impact the leg form22above the knee20, as shown inFIG. 8, to distribute the loading on the leg form22and reduce relative movement between the femur and the tibia.

With reference toFIGS. 2-4, the bumper16includes an air intake64elongated in the cross-vehicle direction CV. The upper beam52is above the air intake64and the lower beam50is below the air intake64.

With continued reference toFIGS. 2-4, the bumper16includes lamp compartments66between the upper beam52and the lower beam50. The bumper16includes lamp compartments66may be above a portion of the cavity18. The upper beam52is above the lamp compartments66and a lower beam50is below the lamp compartments66. The lamp compartments66receive lamps, e.g., fog lamps, as shown inFIG. 1.

A skid plate32abuts the bumper16. For example, the skid plate32abuts the lower beam50below the bumper beam14. The skid plate32extends from the bumper16in the vehicle-rearward direction R. The skid plate32may extend from the bumper16to the frame24. The skid plate32may back the lower beam50to resist rearward twisting of the lower beam50. This may encourage collapse of the lower beam50at the cavity18. The skid plate32follows the contours of the lower beam50. The skid plate32sheds airflow, water, mud, etc. The skid plate32may be plastic or metal.