U.S. patent application number 16/166554 was filed with the patent office on 2020-04-23 for vehicle energy absorber.
This patent application is currently assigned to Ford Global Technologies, LLC. The applicant listed for this patent is Ford Global Technologies, LLC. Invention is credited to CHING-HUNG CHUANG, S.M. ISKANDER FAROOQ, MOHAMMAD OMAR FARUQUE, DEAN M. JARADI, NIRMAL MURALIDHARAN, SRINIVASAN SUNDARARAJAN, NINAD TRIFALE.
Application Number | 20200122662 16/166554 |
Document ID | / |
Family ID | 70279083 |
Filed Date | 2020-04-23 |
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United States Patent
Application |
20200122662 |
Kind Code |
A1 |
FAROOQ; S.M. ISKANDER ; et
al. |
April 23, 2020 |
VEHICLE ENERGY ABSORBER
Abstract
A bumper assembly includes a bumper beam and a fin supported by
the bumper beam. The fin extends along an axis from a proximate end
proximate to the bumper beam to a distal end distal to the bumper
beam. The fin has a sinuous cross section and a thickness each
normal to the axis. The thickness at the distal end is less than
the thickness at the proximate end.
Inventors: |
FAROOQ; S.M. ISKANDER;
(Novi, MI) ; FARUQUE; MOHAMMAD OMAR; (Ann Arbor,
MI) ; CHUANG; CHING-HUNG; (Northville, MI) ;
SUNDARARAJAN; SRINIVASAN; (Ann Arbor, MI) ; TRIFALE;
NINAD; (Farmington Hills, MI) ; MURALIDHARAN;
NIRMAL; (Birmingham, MI) ; JARADI; DEAN M.;
(Macomb, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Ford Global Technologies, LLC |
Dearborn |
MI |
US |
|
|
Assignee: |
Ford Global Technologies,
LLC
Dearborn
MI
|
Family ID: |
70279083 |
Appl. No.: |
16/166554 |
Filed: |
October 22, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60R 2019/1806 20130101;
B60R 19/18 20130101; B60R 19/03 20130101; B60R 2019/186 20130101;
B60R 21/34 20130101; B60R 2019/1893 20130101; B60R 19/04
20130101 |
International
Class: |
B60R 19/18 20060101
B60R019/18; B60R 19/04 20060101 B60R019/04; B60R 21/34 20060101
B60R021/34 |
Claims
1. A bumper assembly, comprising: a bumper beam; and a fin and a
secondary fin each supported by the bumper beam and extending along
an axis from a proximate end proximate to the bumper beam to a
distal end distal to the bumper beam; the fin having a sinuous
cross section and a thickness both taken in a plane normal to the
axis, the thickness at the distal end being less than the thickness
at the proximate end; wherein the distal end of the secondary fin
is disposed between the bumper beam and the distal end of the
fin.
2. The bumper assembly of claim 1, wherein the fin includes a
plurality of segments disposed along the axis from the proximate
end to the distal end, the thickness of each segment decreases
relatively along the axis from the proximate end to the distal
end.
3. The bumper assembly of claim 1, further comprising: a plurality
of fins, the plurality of fins including the fin, each of the
plurality of fins being supported by the bumper beam and each
extending along an axis from a proximate end proximate to the
bumper beam to a distal end distal to the bumper beam, wherein each
fin has a sinuous cross section normal to the respective axis and a
thickness, the thickness at the distal end is less than the
thickness at the proximate end; and a plurality of secondary fins,
the plurality of secondary fins including the secondary fin, each
of the plurality of secondary fins having a sinuous cross section,
and each of the secondary fins being stiffer than the fins.
4. The bumper assembly of claim 3, wherein each of the fins
includes a plurality of segments disposed along the axis from the
proximate end to the distal end, the thickness of each segment
decreases relatively along the axis from the proximate end to the
distal end.
5. The bumper assembly of claim 3, wherein the fins are spaced
along the bumper beam in a cross-vehicle direction.
6. The bumper assembly of claim 3, further comprising a plate
supported by the bumper beam, wherein the fins are supported by the
plate.
7. The bumper assembly of claim 6, wherein the plate extends in a
cross-vehicle direction from a first end to a second end and
includes a center between the first and second ends, the fins
include a first fin attached to the plate between the first end and
the center and a second fin attached to the plate between the
center and the second end, the first fin has a different
orientation that the second fin.
8. The bumper assembly of claim 1, further comprising a fascia,
wherein the fin is disposed between the bumper beam and the
fascia.
9. A bumper assembly, comprising: a bumper beam; a fin and a
secondary fin each supported by the bumper beam and extending along
an axis from a proximate end to a distal end; wherein the fin has a
sinuous cross section normal to the respective axis, and the distal
end of the secondary fin is disposed between the bumper beam and
the distal end of the fin.
10. The bumper assembly of claim 9, wherein the secondary fin has a
sinuous cross section.
11. The bumper assembly of claim 9, wherein the secondary fin is
stiffer than the fin.
12. The bumper assembly of claim 9, wherein the fin has a plurality
of segments disposed along the axis from the proximate end to the
distal end, the thickness of each segment decreases relatively
along the axis from the proximate end to the distal end.
13. The bumper assembly of claim 9, further comprising a plurality
of fins, the plurality of fins including the fin, each of the
plurality of fins being supported by the bumper beam and each
extending along an axis from a proximate end to a distal end,
wherein each fin has a sinuous cross section normal to the
respective axis, and wherein each fin has a plurality of segments
disposed along the respective axis from the respective proximate
end to the respective distal end, the thickness of each segment
decreases relatively along the respective axis from the respective
proximate end to the respective distal end.
14. The bumper assembly of claim 13, further comprising a plurality
of secondary fins, the plurality of secondary fins including the
secondary fin, each of the plurality of secondary fins being
supported by the bumper beam and each extending along an axis from
a proximate end to a distal end, wherein the distal ends of the
secondary fins are disposed between the bumper beam and the distal
ends of the fins.
15. The bumper assembly of claim 14, wherein the distal ends of the
fins each present a flat surface, the flat surfaces of the fins
defining a plane, and each fin has a sinuous cross section in the
plane.
16. The bumper assembly of claim 15, wherein the distal ends of the
secondary fins each present a flat surface, the flat surfaces of
the secondary fins defining a second plane parallel to the
plane.
17. The bumper assembly of claim 16, wherein each secondary fin has
a sinuous cross section in the second plane.
18. The bumper assembly of claim 9, further comprising a plate
supported by the bumper beam, wherein the fin and the secondary fin
are supported by the plate.
19. The bumper assembly of claim 18, wherein the plate extends from
a top to a bottom in a direction transverse to a cross-vehicle
direction, and wherein the fin is disposed adjacent to one of the
top and the bottom of the plate and the secondary fin is disposed
adjacent to the other of the top and the bottom of the plate.
20. The bumper assembly of claim 9, further comprising a fascia,
wherein the fascia covers the fin and the secondary fin.
Description
BACKGROUND
[0001] Vehicle bumpers may have a stiffness determined by the
material and structure of the bumper. However, the desired
stiffness of the bumper may be different depending on vehicle
speed. For example, at a low vehicle speed, a higher stiffness may
be desired to prevent damage to the bumper, while at a high vehicle
speed, a lower stiffness may be desired to absorb energy during a
pedestrian or vehicle impact.
[0002] Several organizations release test protocols and standards
for vehicles directed to specific outcomes. For example, the
Research Council for Automobile Repairs (RCAR) releases impact test
protocols and standards for vehicles. One example RCAR impact test
protocol is directed toward low speed damageability (LSD), i.e.,
damage to vehicle components at 15 kilometers per hour (kph). In
another example, the National Highway Traffic Safety Administration
(NHTSA) releases the Federal Motor Vehicle Safety Standards (FMVSS)
Part 521, which describes impact test protocols for LSD of vehicle
bumper systems. However, as described above, the stiffness of the
bumper system for LSD may differ from the stiffness desired for
pedestrian protection. For example, the European New Car Assessment
Programme (EURO NCAP) protocols for lower leg impact at 40 kph may
be benefited by a lower stiffness for the bumper in comparison to
the stiffness desired for FMVSS protocols for LSD. In other words,
requirements for LSD and pedestrian protection may create competing
design principles. There remains an opportunity to design a vehicle
bumper that accounts for low speed damageability and pedestrian
impact.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 is an exploded view of a vehicle with a bumper
assembly.
[0004] FIG. 2 is a front view of a plurality of fins and a
plurality of secondary fins.
[0005] FIG. 3 is a front view of one of the plurality of fins.
[0006] FIGS. 4A-4B illustrate the bumper assembly impacting an
object.
[0007] FIGS. 5A-5C illustrate the bumper assembly impacting another
object.
DETAILED DESCRIPTION
[0008] A bumper assembly includes a bumper beam and a fin supported
by the bumper beam. The fin extends along an axis from a proximate
end proximate to the bumper beam to a distal end distal to the
bumper beam. The fin has a sinuous cross section and a thickness
each normal to the axis. The thickness at the distal end is less
than the thickness at the proximate end.
[0009] The fin may include a plurality of segments disposed along
the axis from the proximate end to the distal end. The thickness of
each segment decreases relatively along the axis from the proximate
end to the distal end.
[0010] The bumper assembly may include a plurality of fins. The
plurality of fins may include the fin. Each of the plurality of
fins may be supported by the bumper beam and each may extend along
an axis from a proximate end proximate to the bumper beam to a
distal end distal to the bumper beam. Each fin may have a sinuous
cross section and a thickness each normal to the respective axis.
The thickness at the distal end may be less than the thickness at
the proximate end.
[0011] Each of the fins may include a plurality of segments
disposed along the axis from the proximate end to the distal end.
The thickness of each segment may decrease relatively along the
axis from the proximate end to the distal end.
[0012] The fins may be spaced along the bumper beam in a
cross-vehicle direction.
[0013] The bumper assembly may include a plate supported by the
bumper beam. The fins may be supported by the plate.
[0014] The plate may extend in a cross-vehicle direction from a
first end to a second end and includes a center between the first
and second ends. The fins may include a first fin attached to the
plate between the first end and the center and a second fin
attached to the plate between the center and the second end. The
first fin may have a different orientation that the second fin.
[0015] The bumper assembly may include a fascia. The fin is
disposed between the bumper beam and the fascia.
[0016] A bumper assembly includes a bumper beam, a fin, and a
secondary fin each supported by the bumper beam and extending along
an axis from a proximate end to a distal end. The fin has a sinuous
cross section normal to the respective axis. The distal end of the
secondary fin is disposed between the bumper beam and the distal
end of the fin.
[0017] The secondary fin may have a sinuous cross section.
[0018] The secondary fin may be stiffer than the fin.
[0019] The fin may include a plurality of segments disposed along
the axis from the proximate end to the distal end. The thickness of
each segment decreases relatively along the axis from the proximate
end to the distal end.
[0020] The bumper assembly may include a plurality of fins. The
plurality of fins may include the fin. Each of the plurality of
fins may be supported by the bumper beam and each may extend along
an axis from a proximate end proximate to the bumper beam to a
distal end distal to the bumper beam. Each fin may have a sinuous
cross section and a thickness each normal to the respective axis.
Each fin may have a plurality of segments disposed along the
respective axis from the respective proximate end to the respective
distal end, the thickness of each segment decreases relatively
along the respective axis from the respective proximate end to the
respective distal end.
[0021] The bumper assembly may include a plurality of secondary
fins. The plurality of secondary fins may include the secondary
fin. Each of the plurality of secondary fins may be supported by
the bumper beam and each may extend along an axis from a proximate
end to a distal end. The distal ends of the secondary fins may be
disposed between the bumper beam and the distal ends of the
fins.
[0022] The distal ends of the fins each may present a flat surface.
The flat surfaces of the fins may define a plane, and each fin may
have a sinuous cross section in the plane.
[0023] The distal ends of the secondary fins each may present a
flat surface. The flat surfaces of the secondary fins may define a
second plane parallel to the plane.
[0024] Each secondary fin may have a sinuous cross section in the
second plane.
[0025] The bumper assembly may include a plate supported by the
bumper beam. The fin and the secondary fin may be supported by the
plate.
[0026] The plate may extend from a top to a bottom in a direction
transverse to a cross-vehicle direction. The fin may be disposed
adjacent to one of the top and the bottom of the plate, and the
secondary fin may be disposed adjacent to the other of the top and
the bottom of the plate.
[0027] The bumper assembly may include a fascia. The fascia may
cover the fin and the secondary fin.
[0028] With reference to the Figures, wherein like numerals
indicate like parts throughout the several views, a vehicle 10 is
generally shown. The vehicle 10 includes a bumper assembly 12
having a bumper beam 14 and a fin 16 supported by the bumper beam
14. The fin 16 extends along an axis A1 from a proximate end 18
proximate to the bumper beam 14 to a distal end 20 distal to the
bumper beam 14. The fin 16 has a sinuous cross section and a
thickness both taken in a plane normal to the axis A1. The
thickness at the distal end 20 is less than the thickness at the
proximate end 18.
[0029] Additionally, the bumper assembly 12 includes a secondary
fin 22 supported by the bumper beam 14. The secondary fin 22
extends along an axis A2 from a proximate end 24 proximate the
bumper beam 14 to a distal end 26 distal to the bumper beam 14. The
distal end 26 of the secondary fin 22 is disposed between the
bumper beam 14 and the distal end 20 of the fin 16.
[0030] The fin 16 may absorb energy from an object during an
impact, deforming toward the bumper beam 14. By absorbing energy
from the object, the fin 16 may satisfy low speed damageability
(LSD) test protocols and pedestrian protection test protocols. For
example, the fin 16 may have a lower stiffness at the distal end 20
relative to the proximate end 18, i.e., the distal end 20 may be
softer than the proximate end 18. In other words, the stiffness of
the fin 16 may decrease along the axis A1 from the proximate end 18
to the distal end 20. The decreasing stiffness of the fin 16 along
the axis A1 from the proximate end 18 to the distal end 20 provides
specific deformation characteristics for the fin 16 to absorb
energy from the object. For example, the decreasing relative
stiffness along the axis A1 may allow axial deformation, e.g.,
bending, crushing, etc., when absorbing energy from the object,
which may allow deformation at the distal end 20 and resist
deformation at the proximate end 18. Furthermore, the sinuous shape
provides specific deformation characteristics for the fin 16 to
absorb energy from the object. For example, the sinuous shape may
provide axial deformation characteristics when absorbing energy
from the object, which may resist deformation at low speeds and may
allow deformation at high speeds. Thus, the fin 16 with the sinuous
shape may have a high stiffness during a low speed impact and a low
stiffness during a high-speed impact.
[0031] The secondary fin 22 may absorb energy from the object
during the impact, deforming toward the bumper beam 14. By
absorbing energy from the object, the secondary fin 22 may satisfy
low speed damageability (LSD) test protocols. The secondary fin 22
may have a uniform stiffness along the axis A2 from the proximate
end 24 to the distal end 26. The uniform thickness provides
specific deformation characteristics for the secondary fin 22 to
absorb energy from the object. For example, the uniform thickness
may resist axial deformation, e.g., bending, crushing, etc., as
compared to the fin 16. In other words, the secondary fin 22 may
have a higher relative stiffness than the fin 16 to prevent the
object from impacting, i.e., bottoming out against, the bumper beam
14 during the impact.
[0032] As shown in FIG. 1, the vehicle 10 includes the bumper
assembly 12. The bumper assembly 12 may absorb energy during the
impact. The bumper assembly 12 includes the bumper beam 14, a
plurality of fins 16, and a plurality of secondary fins 22. The
fins 16 and the secondary fins 22 are supported by the bumper beam
14, as shown in FIGS. 1-2 and 4A-5C. The fins 16 and the secondary
fins 22 may absorb energy from the impact. The impact may be a dual
stage impact, i.e., the impact may include a first stage and a
second stage. For example, during the first stage of the impact, an
object may contact the fins 16, as shown in FIGS. 4B and 5B,
deforming the fins 16. The object may, for example, be spaced from
the secondary fins 22 during the first stage impact. In other
words, the fins 16 may prevent the object from intruding to the
secondary fins 22. During the second stage of the impact, the
object may contact the secondary fins 22, as shown in FIG. 5C,
deforming the secondary fins 22. In other words, the object may
deform the fins 16 and continue to intrude along the axis A1 to
impact the secondary fins 22.
[0033] With continued reference to FIG. 1, the bumper beam 14 may
extend from a first end 28 to a second end 30 spaced from the first
end 28. The bumper beam 14 may define a longitudinal axis L between
the first end 28 and the second end 30 of the bumper beam 14. The
longitudinal axis L may extend in a cross-vehicle direction, i.e.,
in a direction perpendicular to forward motion of the vehicle 10.
In other words, the bumper beam 14 may be elongated in the
cross-vehicle direction.
[0034] The bumper assembly 12 may include a plate 32, as shown in
FIGS. 1-2 and 4A-5C. The plate 32 may be supported by the bumper
beam 14. The plate 32 may be attached to the bumper beam 14 with a
fastener, e.g., a bolt, a screw, a press-fit dowel, a weld, etc.
The plate 32 may extend along the longitudinal axis L of the bumper
beam 14 from a first end 34 to a second end 36. The first end 34 of
the plate 32 may, for example, be adjacent to the first end 28 of
the bumper beam 14, and the second end 36 of the plate 32 may, for
example, be adjacent to the second end 30 of the bumper beam 14. In
other words, the plate 32 may extend along the bumper beam 14 from
the first end 28 of the bumper beam 14 to the second end 30 of the
bumper beam 14. The plate 32 may be constructed of, e.g., a
plastic, a metal, a composite, etc. The plate 32 may be constructed
of the same material as one of the fin 16 and the secondary fin
22.
[0035] The plate 32 has a center 38, as shown in FIG. 2. The center
38 of the plate 32 may divide the plate 32 into a first side 40 and
a second side 42. The center 38 may be disposed between the first
end 34 of the plate 32 and the second end 36 of the plate 32. The
center 38 may be disposed substantially halfway between the first
end 34 of the plate 32 and the second end 36 of the plate 32. The
first side 40 of the plate 32 may, for example, extend from the
first end 34 of the plate 32 to the center 38 of the plate 32, and
the second side 42 of the plate 32 may, for example, extend from
the second end 36 of the plate 32 to the center 38 of the plate
32.
[0036] The plate 32 may include a top 44 and a bottom 46 spaced
from the top 44 in a direction transverse to the longitudinal axis
L, i.e., the cross-vehicle direction, as shown in FIG. 2. The top
44 and the bottom 46 may each extend from the first end 34 of the
plate 32 to the second end 36 of the plate 32. In other words, the
top 44 and the bottom 46 may each be elongated along the
longitudinal axis L.
[0037] The bumper assembly 12 may include a fascia 48, as shown in
FIG. 1. The fascia 48 may be supported by the bumper beam 14. For
example, the fascia 48 may be attached to a body (not numbered)
and/or to the bumper beam 14. The fascia 48 may be a portion of an
exterior of the vehicle 10. In other words, the fascia 48 may cover
the bumper beam 14. For example, the fascia 48 may extend along the
bumper beam 14 from the first end 28 to the second end 30, i.e.,
along the longitudinal axis L. The fascia 48 may be spaced from the
bumper beam 14, e.g., in a vehicle fore-and-aft direction. In other
words, the fascia 48 and the bumper beam 14 may define a cavity 50
therebetween.
[0038] The fins 16 and secondary fins 22 may be disposed in the
cavity 50, i.e., between the bumper beam 14 and the fascia 48, as
shown in FIG. 1. The fins 16 and the secondary fins 22 may be
supported by the plate 32 in the cavity 50. The fins 16 and the
secondary fins 22 may each extend across the cavity 50, e.g., in
the vehicle fore-and-aft direction, from the bumper beam 14 toward
the fascia 48. The fins 16 extend farther across the cavity 50,
e.g., in the vehicle fore-and-aft direction, then the secondary
fins 22, as set forth further below.
[0039] The fins 16 each have a proximate end 18 and a distal end
20, as shown in FIGS. 1 and 4A-5C. Each fin 16 defines the axis A1
from the proximate end 18 to the distal end 20. In FIGS. 1 and
4A-5C, the axis A1 is shown for one of the fins 16, and the other
fins 16 may extend along respective axes parallel to the axis A1.
Alternatively, the fins 16 may not be parallel to each other, i.e.,
the respective axes may not be parallel to the axis A1. Each
respective axis A1 extends from the respective proximate end 18 to
the respective distal end 20. The proximate end 18 is proximate to
the bumper beam 14, and the distal end 20 is distal to the bumper
beam 14. The proximate end 18 may be attached to the plate 32.
Alternatively, the proximate end 18 may be integral with the plate
32, i.e., formed as a unitary construction. The distal end 20 may
receive the object during the first stage impact, as shown in FIGS.
4B and 5B. Thus, the distal end 20 may deform relative to the
proximate end 18 during the impact.
[0040] Each fin 16 has a respective proximate end 18 and a
respective distal end 20. Each fin 16 may extend from the proximate
end 18 to the distal end 20 along the axis A1. Each proximate end
18 of each fin 16 may present a proximal flat surface 52. The
proximal flat surfaces 52 may contact the plate 32. For example,
the proximal flat surface 52 may be attached to the plate 32, e.g.,
with an adhesive, a braze, a weld, etc. Each distal end 20 of each
fin 16 may present a distal flat surface 54. The distal flat
surfaces 54 may receive the object during the first stage impact.
The distal flat surfaces 54 may define a plane C, as shown in FIGS.
1 and 3.
[0041] Each fin 16 may have a plurality of segments 56, 58, 60
disposed along the axis A1 from the proximate end 18 to the distal
end 20. For example, as shown in FIGS. 1, 3, and 4A-5C, each fin 16
may have a first segment 56, a second segment 58, and a third
segment 60. The first segment 56 may be disposed adjacent to the
proximate end 18, the third segment 60 may be disposed adjacent to
the distal end 20, and the second segment 58 may be disposed
between the first segment 56 and the third segment 60. The second
segment 58 may be sandwiched between the first segment 56 and the
third segment 60. In other words, the first segment 56 may extend
from the proximate end 18 to the second segment 58, and the third
segment 60 may extend from the distal end 20 to the second segment
58. The fin 16 may have any suitable number of segments 56, 58,
60.
[0042] Each segment 56, 58, 60 may extend any suitable amount along
the axis A1. The segments 56, 58, 60 may, for example, extend
different amounts along the axis A1. As one example, the first
segment 56 and the second segment 58 may extend farther along the
axis A1 than the third segment 60, as shown in FIGS. 1, 4A-5C.
Also, the first segment 56 may extend farther along the axis A1
than the second segment 58, as shown in FIGS. 1, 4A-5C. As another
example, the second segment 58 may extend farther along the axis A1
than the first segment 56. Alternatively, each of the segments 56,
58, 60 may extend the same amount along the axis A1.
[0043] With reference to FIG. 3, the thickness, i.e., material
thickness, is taken in a plane normal to the axis A1. The thickness
of each segment 56, 58, 60 decreases relatively along the axis A1
from the proximate end 18 to the distal end 20. In other words, the
thickness of the fin 16 is greater in the first segment 56, i.e.,
adjacent to the proximate end 18, than in the third segment 60,
i.e., adjacent to the distal end 20. For example, the first segment
56 may have a first thickness T1, the second segment 58 may have a
second thickness T2, and the third segment 60 may have a third
thickness T3. The first thickness T1 is greater than each of the
second thickness T2 and the third thickness T3. Additionally, the
second thickness T2 is greater than the third thickness T3. The
fins 16 may include a transition between each of the segments 56,
58, 60. The transition may be rounded or angular.
[0044] The thickness of the fins 16 may be uniform along each
segment 56, 58, 60. In other words, the thickness of each segment
56, 58, 60 may be constant along the axis A1. The thickness at each
segment 56, 58, 60, i.e., the first thickness T1, the second
thickness T2, and the third thickness T3, may be directly
proportional to the stiffness of each segment 56, 58, 60. For
example, the first segment 56 is stiffer than each of the second
segment 58 and the third segment 60. Additionally, the second
segment 58 is stiffer than the third segment 60. In other words,
the stiffness of the fin 16 decreases along the axis A1 from the
proximate end 18 to the distal end 20, i.e., from the first segment
56 to the third segment 60.
[0045] Each fin 16 has a cross section, as shown in FIG. 3. The
cross section has a sinuous shape, i.e., serpentine, wavy, etc. The
sinuous shape may be a repeating pattern of curves in opposite
directions, i.e., in the shape of a sine wave. The cross section
has a sinuous shape taken in a plane normal to the axis A1. The
cross section may be sinuous from the proximate end 18 to the
distal end 20, i.e., in any plane therebetween. For example, the
cross section is sinuous in the plane C defined by the distal flat
surfaces 54. That is, the axis A1 may be normal to the plane C. The
sinuous shape may be substantially S-shaped. The sinuous cross
section may provide deformation characteristics for the fin 16 that
are similar to a closed cylindrical tube. Furthermore, the sinuous
cross section may provide the tube-like deformation characteristics
to a shape that is not a closed circle, e.g., the sinuous shape
extending along the rectangular bumper beam 14. Thus, the fin 16
can provide specific deformation characteristics for various shapes
of bumper assemblies.
[0046] With reference to FIG. 3, the sinuous shape includes a
plurality of curves. For example, the sinuous shape may include a
first curve 62, a second curve 64, a third curve 66, and a fourth
curve 68. The first curve 62 defines a first opening 70, the second
curve 64 defines a second opening 72, the third curve 66 defines a
third opening 74, and the fourth curve 68 defines a fourth opening
76. Each of the curves may be substantially C-shaped.
[0047] With continued reference to FIG. 3, the sinuous shape may
define a first center line D and a second center line E in the
plane C. The sinuous shape may be symmetric about the second center
line E. The first and third openings 70, 74 may oppose the second
and fourth openings 72, 76 about the first center line D. The first
and second openings 70, 72 may oppose the third and fourth openings
74, 76 about the second center line E. The sinuous shape may define
a mirror image about the second center line E.
[0048] As shown in FIGS. 1-2 and 4A-5B, the fins 16 may be disposed
adjacent to the bottom 46 of the plate 32. The fins 16 may be
spaced from each other along the bumper beam 14. For example, the
fins 16 may be spaced from each other along the longitudinal axis L
of the bumper beam 14, i.e., in the cross-vehicle direction, from
the first end 34 of the plate 32 to the second end 36 of the plate
32. The fins 16 may be spaced evenly along the bumper beam 14.
Alternatively, the spacing between the fins 16 may vary.
[0049] The fins 16 may be spaced to provide specific deformation
characteristics during the vehicle impact. A first fin 16a may be
attached to the first side 40 of the plate 32, and a second fin 16b
may be attached to a second side 42 of the plate 32, as shown in
FIG. 2. Each fin 16 may have a fin orientation, i.e., a position of
the fin 16 on the plate 32 about one or more of the axis A1, the
first center line D, and the second center line E. The first fin
16a may have a different orientation than the second fin 16b, as
shown in FIG. 2, e.g., the fin orientation of the first fin 16a may
mirror the fin orientation of the second fin 16b. Alternatively,
the first fin 16a may have a fin orientation transverse to a fin
orientation of the second fin 16b.
[0050] The secondary fins 22 each have a proximate end 24 and a
distal end 26, as shown in FIGS. 1 and 5A-5C. Each secondary fin 22
defines the axis A2 from the proximate end 24 to the distal end 26.
In FIGS. 1 and 5A-5C, the axis A2 is shown for one of the secondary
fins 22, and the other secondary fins 22 may extend along
respective axes parallel to the axis A2. Alternatively, the
secondary fins 22 may not be parallel to each other, i.e., the
respective axes may not be parallel to the axis A2. The secondary
fins 22 may extend parallel to the fins 16, i.e., the respective
axes of the secondary fins 22 may be parallel to the respective
axes of the fins 16. Alternatively, the secondary fins 22 may not
be parallel with the fins 16. Each respective axis A2 extends from
the respective proximate end 24 to the respective distal end
26.
[0051] The proximate end 24 is proximate to the bumper beam 14, and
the distal end 26 is distal to the bumper beam 14. The proximate
end 24 may be attached to the plate 32. Alternatively, the
proximate end 24 may be integral with the plate 32, i.e., formed as
a unitary construction. The distal end 26 may receive the object
during the second stage impact, as shown in FIG. 5C. Thus, the
distal end 26 may deform relative to the proximate end 24 during
the second stage impact.
[0052] Each secondary fin 22 has a respective proximate end 24 and
a respective distal end 26. Each secondary fin 22 may extend from
the proximate end 24 to the distal end 26 along the axis A2. Each
proximate end 24 of each secondary fin 22 may present a proximal
flat surface 78. The proximal flat surfaces 78 may contact the
plate 32. For example, the proximal flat surface 78 may be attached
to the plate 32, e.g., with an adhesive, a braze, a weld, etc. Each
distal end 26 of each secondary fin 22 may present a distal flat
surface 80. The distal flat surfaces 80 may receive the object
during the second stage impact. The distal flat surfaces 80 may
define a second plane P, as shown in FIG. 1.
[0053] The second plane P is disposed between the plane C and the
bumper beam 14, as shown in FIG. 1. In other words, the distal ends
26 of the secondary fins 22 are disposed between the bumper beam 14
and the distal ends 20 of the fins 16. The secondary fins 22, for
example, are spaced from the fascia 48, and the fins 16, for
example, may abut the fascia 48. Specifically, the distal ends 26
of the secondary fins 22 are spaced from the fascia 48, and the
distal ends 20 of the fins 16 may abut the fascia 48. In other
words, the secondary fins 22 extend partially across the cavity 50
from the bumper beam 14 toward the fascia 48, and the fins 16 may
extend entirely across the cavity 50, e.g., from the bumper beam 14
to the fascia 48. Alternatively, the fins 16 may be spaced from the
fascia 48. In other words, the distal ends 20 of the fins 16 may be
spaced from the fascia 48. In this situation, the fins 16 extend
partially across the cavity 50 toward the fascia 48 farther than
the secondary fins 22.
[0054] Each secondary fin 22 may have a cross section in the second
plane P, i.e., normal to the respective axis A2. The cross section
of each secondary fin 22 may be any suitable shape, e.g., circular,
rectangular, etc. The cross section of the secondary fin 22 may,
for example, have a sinuous shape in a plane normal to the
respective axis A2. The cross section may be sinuous from the
proximate end 24 to the distal end 26, i.e., in any plane
therebetween. In this situation, the cross section of the secondary
fin 22 may be sinuous in the second plane P defined by the distal
flat surfaces 80 of the secondary fins 22.
[0055] As shown in FIGS. 1 and 2, the secondary fins 22 may be
disposed adjacent to the top 44 of the plate 32, i.e., the
secondary fins 22 may be disposed above the fins 16. Alternatively,
the fins 16 may be disposed adjacent to the top 44 of the plate 32,
and the secondary fins 22 may be disposed adjacent to the bottom 46
of the plate 32. The secondary fins 22 may be spaced from each
other along the longitudinal axis L of the bumper beam 14. The
secondary fins 22 may, for example, extend from each end 34, 36 of
the plate 32 toward the center 38 of the plate 32. As shown in FIG.
2, the secondary fins 22 extend along the longitudinal axis L from
each end 34, 36 of the plate 32 to a position spaced from the
center 38 of the plate 32, i.e., the secondary fins 22 may be
spaced from the center 38 of the plate 32 along the longitudinal
axis L. Alternatively, the secondary fins 22 may extend from each
end 34, 36 of the plate 32 to the center 38 of the plate 32.
[0056] The secondary fins 22 may be spaced to provide specific
deformation characteristics during the vehicle impact. The
secondary fins 22 may have a same or different spacing as the fins
16 along the longitudinal axis L. For example, the secondary fins
22 may be closer together than the fins 16, as shown in FIG. 2.
Each of the secondary fins 22 may have a fin orientation, i.e., a
position of the secondary fin 22 on the plate 32. The secondary
fins 22 disposed on the first side 40 of the plate 32 may have a
different orientation than the secondary fins 22 disposed on the
second side 42 of the plate 32. For example, the secondary fins 22
disposed on the first side 40 of the plate may have the same
orientation as the first fin 16a, and the secondary fins 22
disposed on the second side 42 of the plate 32 may have the same
orientation as the second fin 16b, as shown in FIG. 2, e.g., the
fin orientation of the secondary fins 22 disposed on the first side
40 of the plate 32 may mirror the fin orientation of the secondary
fins 22 disposed on the second side 42 of the plate 32.
Alternatively, the secondary fins 22 disposed on the first side 40
of the plate 32 may have a fin orientation transverse to a fin
orientation of the secondary fins 22 disposed on the second side 42
of the plate 32.
[0057] The secondary fins 22 are more resistive to deformation,
i.e., stiffer, than the fins 16. The fins 16 and the secondary fins
22 may, for example, be constructed of a different material. As one
example, the material of the fins 16 may have a higher ductility,
i.e., a percentage of elongation, than the material of the
secondary fins 22. In other words, the fins 16 may be formed of a
softer material than the secondary fins 22. Alternatively, the
secondary fins 22 may have a thickness, i.e., a width along the
longitudinal axis L the same or greater than the thickness of the
first segment 56 of the fins 16. In other words, the secondary fins
22 may be at least as stiff as the first segment 56 of the fins 16,
i.e., stiffer than the second segment 58 and the third segment 60.
The fins 16 and the secondary fins 22 may be constructed of any
suitable material, e.g., a polymer, a plastic, a thermoplastic, a
metal, a composite, etc.
[0058] The bumper assembly 12 may absorb energy during a high-speed
impact test. The high-speed impact test may be a high-speed
pedestrian impact test, e.g., a European New Car Assessment Program
(EURO NCAP) Pedestrian Testing Protocol Version 8.4 (November
2017), that simulates an impact between a pedestrian's leg and the
vehicle 10. The test uses a legform 82, which is a test device
including a plurality of sensors (not shown) designed to simulate a
human leg. In the high-speed pedestrian impact test, the legform 82
is attached to a launcher (not shown), e.g., an air, spring, or
hydraulic gun, in front of the vehicle 10. The launcher propels the
legform 82 toward the vehicle 10 and into the bumper assembly 12.
The launcher is positioned to propel the legform 82 at a specific
angle relative to the axis A1, e.g., 0 degrees to simulate a front
impact. The launcher propels the legform 82 to the bumper assembly
12 such that the legform 82 moves at 11.11 meters per second (40
kilometers per hour) upon contacting the bumper assembly 12. A
computer (not shown) collects data from the sensors in the legform
82 on the forces and moments applied to different parts of the
legform 82, e.g., parts representing an upper femur, a lower tibia,
a knee, a position above the knee (e.g. 40 mm), and a position
below the knee (e.g., 40 mm).
[0059] FIGS. 4A-4B show the legform 82 impacting the vehicle 10 in
a high-speed pedestrian impact test. FIG. 4A shows the legform 82
prior to impacting the bumper assembly 12, and FIG. 4B shows the
legform 82 upon impacting the bumper assembly 12 in the first stage
impact. Upon impact, the legform 82 engages one or more fins 16,
deforming the distal ends 20 of the fins 16 toward the plate 32.
Because the thickness at the distal end 20 is less than the
thickness at the proximate end 18, i.e., the fin 16 is stiffer at
the proximate end 18 than the distal end 20, the fin 16 may axially
deform, e.g., bend, crush, etc., absorbing energy from the legform
82 and reducing acceleration of the legform 82 during impact.
Furthermore, in the impact shown in FIGS. 4A-4B, only a few of the
plurality of fins 16 receive the legform 82, providing a controlled
deceleration and controlled movement of the legform 82 as the fins
16 deform and absorb energy from the legform 82. Thus, the impulse
from the impact is spread over a longer time during the impact,
reducing impact energy transmitted to the legform 82. In this
situation, the fins 16 may prevent intrusion of the legform 82 to
the secondary fins 22. In other words, the fins 16 may absorb the
energy of the legform 82 such that the legform 82 remains spaced
from the secondary fins 22.
[0060] The bumper assembly 12 may absorb energy during a low speed
vehicle impact test. The low speed vehicle impact test may be an
RCAR low speed damageability test or an Insurance Institute for
Highway Safety (IIHS) bumper test. The test uses an impact barrier
84 that simulates an end of another vehicle. The impact barrier 84
may be a rigid object with an energy absorber designed to simulate
a bumper on another vehicle. The vehicle 10 moves toward the impact
barrier 84 at a specified speed, e.g., 15-16 kilometers per hour,
such that the bumper assembly 12 impacts the impact barrier 84.
Upon impacting the impact barrier 84, the vehicle 10 decelerates.
Images of the bumper assembly 12 are collected to measure the
deformation of the bumper assembly 12, e.g., the deformation of the
fins 16.
[0061] FIGS. 5A-5C show the impact barrier 84 impacting the vehicle
10 in a low speed damageability test. FIG. 5A shows the impact
barrier 84 prior to impacting the bumper assembly 12, FIG. 5B shows
the impact barrier 84 upon impacting the fins 16 in the first stage
impact, and FIG. 5C shows the impact barrier 84 upon impacting the
secondary fins 22 in the second stage impact. During the first
stage, the impact barrier 84 may engage the distal ends 20 of the
fins 16. In this situation, most or all of the plurality of fins 16
may engage the impact barrier 84, distributing the impact load and
reducing the force on each individual fin 16. The fins 16 absorb
energy from the impact barrier 84 while reducing the deformation in
each individual fin 16. Thus, the fins 16 reduce intrusion of any
specific part of the impact barrier 84 to the vehicle 10, improving
low speed damageability. The impulse from the first stage impact is
spread over a longer time during the impact, reducing impact energy
transmitted to the impact barrier 84.
[0062] During the second stage, the impact barrier 84 may impact
the distal ends 26 of the secondary fins 22. In other words, the
impact barrier 84 may have deformed the fins 16, i.e., one or more
segments 56, 58, 60, in the first stage impact and continued to
intrude toward the bumper beam 14. In this situation, most or all
of the plurality of secondary fins 22 may engage the impact barrier
84, distributing the impact load and reducing the force on each
individual secondary fin 22. The secondary fins 22 absorb energy
from the impact barrier 84 while reducing the deformation of each
individual secondary fin 22. Thus, the secondary fins 22 reduce
intrusion of any specific part of the impact barrier 84 to the
vehicle 10. Furthermore, the secondary fins 22 prevent the impact
barrier 84 from impacting the bumper beam 14, i.e., bottoming out
against the bumper beam 14, improving low speed damageability. The
impulse from the second stage impact is spread over a longer time
during the impact, reducing impact energy transmitted to the impact
barrier 84.
[0063] The disclosure has been described in an illustrative manner,
and it is to be understood that the terminology which has been used
is intended to be in the nature of words of description rather than
of limitation. Many modifications and variations of the present
disclosure are possible in light of the above teachings, and the
disclosure may be practiced otherwise than as specifically
described.
* * * * *