U.S. patent application number 09/903232 was filed with the patent office on 2002-01-17 for automobile bumper core.
Invention is credited to Hattori, Shozo, Tamada, Teruo.
Application Number | 20020005644 09/903232 |
Document ID | / |
Family ID | 27481454 |
Filed Date | 2002-01-17 |
United States Patent
Application |
20020005644 |
Kind Code |
A1 |
Tamada, Teruo ; et
al. |
January 17, 2002 |
Automobile bumper core
Abstract
The automobile bumper core according to the present invention
provides greater impact absorbing qualities from impact forces. The
core (3) comprises a surface wall (8) and an opposing rear wall
(9), with a pair of opposing side walls (7). In one embodiment
there are a plurality of ribs (10) and a plurality of hollow
portions (6) between the surface wall (8) and the rear wall (9).
The bumper core is intended to be disposed inside the bumper fascia
(2) and the resulting bumper is attached to the automobile.
Inventors: |
Tamada, Teruo;
(Yokohama-City, JP) ; Hattori, Shozo;
(Nagoya-city, JP) |
Correspondence
Address: |
MAINE & ASMUS
100 MAIN STREET
P O BOX 3445
NASHUA
NH
03061-3445
US
|
Family ID: |
27481454 |
Appl. No.: |
09/903232 |
Filed: |
July 11, 2001 |
Current U.S.
Class: |
293/120 |
Current CPC
Class: |
B60R 19/18 20130101;
B60R 19/04 20130101; B60R 2019/188 20130101; B60R 2019/184
20130101 |
Class at
Publication: |
293/120 |
International
Class: |
B60R 019/03 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 14, 2000 |
JP |
2000-215083 |
Jul 14, 2000 |
JP |
2000-215084 |
Jul 14, 2000 |
JP |
2000-215085 |
Dec 19, 2000 |
JP |
2000-385930 |
Claims
What is claimed is:
1. An impact absorbing automobile bumper, comprising: a bumper
fascia and one or more bumper core sections, said bumper core
sections having a surface wall and an opposing rear wall, a pair of
opposing sidewalls, and wherein said bumper core sections have one
or more ribs and a plurality of hollow portions between said
surface wall and said rear wall, and wherein said surface wall
attaches to an inner surface of said bumper fascia.
2. The automobile bumper according to claim 1, wherein said bumper
fascia is attached to an automobile in a longitudinal manner,
wherein said bumper core sections are affixed to said inner surface
of the bumper fascia at a driver side and a passenger side.
3. The automobile bumper according to claim 1, wherein said bumper
core sections are composed of thermoplastic resin wherein a modulus
of flexural elasticity is 10000 kg/cm.sup.2 to 40000 kg/.sup.2 and
the overall mean wall thickness is 0.5 mm to 4.0 mm, and the
product of modulus of flexural elasticity and mean wall thickness
is 1000 kg/cm to 10000 kg/cm.
4. The automobile bumper according to claim 1, wherein said ribs
are hollow concave ribs having a midsection fusing portion and
outwardly expanding from said fusing portion to said surface wall
and said rear wall and having a hole opening at both said surface
and said rear wall.
5. The automobile bumper according to claim 4, wherein said bumper
core is an integral structure by forming said concave ribs and
abutting and fusing in said hollow portions.
6. The automobile bumper according to claim 1, wherein said ribs
are hollow conical ribs extending between said surface wall and
said rear wall, having a hole opening on either said surface wall
or said rear wall.
7. The automobile bumper according to claim 6, wherein said concave
ribs are angularly projecting with an angle .alpha. in the range of
5 to 30 degrees, and an end diameter .beta. is in the range of 10
to 40 mm.
8. The automobile bumper according to claim 1, further comprising
one or more sidewall ribs, wherein a portion of said sidewalls is
indented into said hollow portion to form said sidewall ribs.
9. The automobile bumper according to claim 8, wherein said
sidewall ribs are angularly projecting with an angle x in the range
of 5 to 30 degrees, and the radius y in the range of 5 to 20
mm.
10. The automobile bumper according to claim 1, wherein said
sidewall has an inclination angle in the range of 0 to 50
degrees.
11. The automobile bumper according to claim 1, wherein said ribs
are inner ribs projecting substantially perpendicular from said
surface wall to said rear wall.
12. The automobile bumper according to claim 11, further comprising
a buried plate disposed substantially parallel to said inner
ribs.
13. The automobile bumper according claim 1, further comprising a
plurality of coupling ribs for integrally linking said concave
ribs, wherein said coupling ribs are longitudinal sections
interconnecting said concave ribs and disposed on either said
surface wall or said rear wall.
14. The automobile bumper according to claim 13, wherein said
coupling ribs are formed in a longitudinal groove.
15. The automobile bumper according to claim 13, wherein said
coupling ribs are formed in a V-shaped groove
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U. S. C. Section
119 from Japanese Patent Application No. 2000-215083, No.
2000-215084, and No. 2000-215085 filed on Jul. 14, 2000 and a
Japanese Patent Application No. 2000-385930 filed on Dec. 19, 2000,
which is incorporated herein for all purpose.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a bumper for an automobile,
and more particularly to a bumper core that is excellent in impact
absorption and integrally disposed in the bumper.
[0003] Automobile bumpers ideally provide protection in the event
of serious collisions. It is also desired that the bumper have
energy absorbing properties to lessen the severity of the
accident.
[0004] Bumpers should have the ability to deform during smaller
accidents and to return to the original shape without incurring
expensive repairs. In addition to these concerns, there are also
automotive requirements that ensure the bumpers can withstand
certain safety requirements.
[0005] While most vehicles have both front and rear bumpers, the
automobile industry recognizes that the requirements differ between
the front and rear bumpers. Front bumpers are usually configured to
have greater rigidity in order to accommodate a more severe crash.
Rear bumpers generally are made to absorb less severe crashes and
to return to the original shape in minor collisions.
[0006] The more common bumper has an outer shell and a rigid bumper
beam. The bumper beam is a longitudinal reinforcing member,
generally tubular, that is affixed to the car body. This metal
reinforcing member provides the structural strength in the event of
a collision. These are well known in the art and provide
satisfactory protection for severe crashes. In minor collisions
these bumpers tend to be easily dented and damaged. Thus, repair
costs are higher on these vehicles, which affects insurance
characteristics, such as the one disclosed in Japanese Patent
Application Laid-open No. 3-125649.
[0007] Also in the prior art is the use of foam cores that are used
primarily in rear bumpers, but also in some front bumpers depending
upon the type of vehicle and the cost. It is well known in the
industry that to enable a more satisfactory bumper design, it is
necessary to combine an outer skin or fascia, some compressible
impact absorbing member and a rigid longitudinal member. The foam
cores provide some protection in minor crashes by returning the
bumper to the original shape. The prior art describes automobile
bumpers with an impact absorbing member and front and rear tubular
beam reinforcing members disposed inside of a bumper fascia.
[0008] In the automobile bumper disclosed in JP-A No. 3-125649, the
impact absorbing member and beam reinforcing member are both
arranged inside the bumper fascia. However, since the spacing
between the bumper fascia and the car body is narrow, it is hard to
obtain a sufficient thickness of the impact absorbing member and
beam reinforcing member combined in the longitudinal direction for
absorbing impact from the outside. This is particularly evident in
the rear bumper having a thin and curved shape. These prior art
bumper foam members also are expensive to manufacture and integrate
into the bumper assemblies. Thus, the prior art foam core is
expensive to integrate into a bumper and also has poor impact
absorbing properties.
[0009] Thus, the prior art design provides insufficient impact
absorbing properties and the bumper is likely to suffer denting and
damage from even low level impacts. What is needed is a bumper core
that is cost-effective to manufacture and install within the
bumpers. This bumper core should be designed to withstand
significant impact forces and still return to the original shape of
the bumper. Such a bumper should increase safety margins as well as
lower insurance costs for minor collisions.
SUMMARY OF THE INVENTION
[0010] The present invention has been achieved in view of the
above-described problems of conventional technologies.
[0011] Accordingly, the invention provides for an automobile
bumper, comprising a bumper fascia having at least one impact
absorbing bumper core attached to an inner surface thereof, the
bumper core comprising a hollow body defined by a surface wall
attached to the bumper fascia, a rear wall opposed thereto, and a
pair of opposed side walls, wherein at least one rib extends within
the body from the surface wall to the rear wall. The bumper core is
disposed between the inside of the bumper fascia and the car body
in a hollow double wall structure in order to provide a bumper
which has excellent impact absorption from the outside and is also
superb in safety. This bumper provides impact absorbing qualities
even in a structure with a thin bumper core in the longitudinal
direction between the inside of the bumper fascia and car body,
such as the rear bumper.
[0012] The automobile bumper cores may be interposed between the
bumper fascia and the car body at the inside right and left
positions as separate units. The bumper cores are formed in a
hollow double wall structure by blow molding of thermoplastic resin
as a molded body having a hollow part and having sidewalls upright
in the longitudinal direction of the bumper fascia. These units are
produced as separate units for the right and left sides of the
bumper and easily installed by adhesive or other means known in the
art.
[0013] The automobile bumper cores of the present invention are
preferably composed of thermoplastic resin, and even more
preferable if having a modulus of flexural elasticity is 10000
kg/cm.sup.2 to 40000 kg/cm.sup.2, and the overall mean wall
thickness is 0.5 mm to 4.0 mm, and the product of modulus of
flexural elasticity and mean wall thickness is 1000 kg/cm to 10000
kg/cm.
[0014] The present invention provides an impact absorbing
automobile bumper core, comprising a surface wall and an opposing
rear wall, and with a pair of opposing sidewalls. The bumper core
has one or more ribs and a plurality of hollow portions between
said surface wall and said rear wall, and wherein said surface wall
attaches to an inner surface of a bumper fascia and said rear wall
is attached to an automobile.
[0015] The automobile bumper has one or more bumper cores formed in
a structure having a buffer section composed of a rib for linking
between the surface wall corresponding to the inside of the bumper
fascia and the rear wall corresponding to the car body.
[0016] The impact absorbing automobile bumper core may comprise a
surface wall and an opposing rear wall, and a pair of opposing
sidewalls. The bumper core has one or more ribs and a plurality of
hollow portions between the surface wall and said rear wall, and
wherein the surface wall attaches to an inner surface of a bumper
fascia. The bumper fascia can attach directly to the car body or
connect to a longitudinal structure that is attached on some
automobiles.
[0017] The bumper fascia may be attached in a longitudinal manner
to an automobile in a longitudinal manner having a driver side
section and a passenger side section, wherein said bumper core
sections are affixed to said inner surface of the bumper fascia at
a driver side and a passenger side.
[0018] The rib for linking between the surface wall corresponding
to the inside of the bumper fascia and the rear wall corresponding
to the car body may be composed of plural concave ribs. The concave
ribs are preferably formed in a circular or elliptical sectional
shape.
[0019] The bumper core are preferably characterized by an integral
structure in which the concave ribs composing the buffer section
are formed from the surface wall and rear wall, and abutting and
fusing in the hollow space.
[0020] The circular concave ribs preferably contract in diameter in
the hollow space direction from the opening end of the surface wall
or rear wall, the diameter of the contracting angle .alpha. being 5
to 30 degrees, and the diameter .beta. of the opening end being 10
to 40 mm.
[0021] In one embodiment, part of the sidewall of the bumper core
is indented to the hollow space side to form ribs of the molded
body. The rib portion may be formed by indenting part of the
sidewall of the bumper core to the hollow space side is
semicircular, the rib portion being contracted in diameter in the
hollow space direction from the opening end of the surface wall or
rear wall of the impact absorbing member, the diameter contracting
angle .alpha. is suitably 5 to 30 degrees, and the radius .beta. of
the opening end is suitably 5 to 20 mm.
[0022] The bumper cores may have a plurality of coupling ribs for
integrally linking the plurality of concave ribs. Each coupling rib
of the bumper cores is preferably a longitudinal rib extending from
the surface wall in the rear wall direction, or from the rear wall
in the surface wall direction.
[0023] The bumper of the invention provides impact absorbing
qualities even in a structure with a thin bumper core in the
longitudinal direction between the inside of the bumper fascia and
car body, such as the rear bumper.
[0024] Still other objects and advantages of the present invention
will become readily apparent to those skilled in this art from the
following detailed description. As will be realized, the invention
is capable of other and different embodiments, and its several
details are capable of modifications in various obvious respects,
all without departing from the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The present invention will be readily understood by the
following detailed description in conjunction with the accompanying
drawings, wherein like reference numerals designated like
structural elements, and in which:
[0026] The drawings illustrate the rear bumper as an example of the
bumper for automobile according to an embodiment of the
invention.
[0027] FIG. 1 is an overall perspective view of a rear bumper as
seem from inside.
[0028] FIG. 2 is a section view in X-X direction in FIG. 1.
[0029] FIG. 3 is a sectional view showing a detailed structure of a
bumper core in a first embodiment.
[0030] FIG. 4 is a sectional view showing a sectional structure of
a bumper core in a second embodiment.
[0031] FIG. 5 is a sectional view showing a sectional structure of
a bumper core in a third embodiment.
[0032] FIG. 6 is a sectional view showing a sectional structure of
a bumper core in a fourth embodiment.
[0033] FIG. 7 is a sectional view showing a sectional structure of
a bumper core in a fifth embodiment.
[0034] FIG. 8 is a front view of a bumper core in a sixth
embodiment.
[0035] FIG. 9 is a sectional view in Y-Y direction in FIG. 8.
[0036] FIG. 10 is a sectional view in Z-Z direction in FIG. 8.
[0037] FIG. 11 is a perspective view showing an essential section
of FIG. 8.
[0038] FIG. 12 is a perspective view showing other example of FIG.
11.
[0039] FIG. 13 is a perspective view showing another example of
FIG. 11.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0040] It is understood that the preferred description is a
presentation of one or more embodiments of the invention and is not
specifically limited or narrowed by this particular description. In
FIG. 1, numeral 1 is a rear bumper. The rear bumper I comprises a
bumper fascia 2 and a pair of bumper cores 3 for absorbing impact
from the outside. The bumper cores 3 are interposed at the right
and left positions between the bumper fascia 2 and the car body.
The bumper fascia and bumper core making up the bumper assembly,
which is affixed directly to the automobile. The bumper assembly of
the present invention can also be attached to a longitudinal
support that is part of the vehicle and provides greater collision
safety.
[0041] The right and left sides of the bumper fascia 2 are formed
in a curvature along the side surface of the car body, and at the
inside of the curved portions 4 there is an affixing portion 5 for
affixing to the car body by screwing or fastening. In one
embodiment the bumper fascia 2 is made of thermoplastic resin.
Although the rear bumper is described, it is within the scope of
the invention to incorporate the bumper cores in either front or
rear bumpers.
[0042] As shown in FIG. 2, the right bumper core 3 as seem from the
inside of the bumper fascia 2 has a hollow part 6 in a hollow
double wall structure by blow molding of thermoplastic resin, and
it is a closed hollow molded body having upright sidewalls 7 in the
longitudinal direction of the bumper fascia 2. This bumper core 3
has a rib 10 for linking between a surface wall 8 corresponding to
the inside of the bumper fascia 2 and a rear wall 9 corresponding
to the car body (not shown). The rib 10 is composed of concave ribs
10a, 10b formed respectively from the surface wall 8 and rear wall
9, being mutually fused inside the hollow portion 6 to be formed
into an integral shape, and 10c is a fused plate portion. The
concave ribs 10a, 10b are circular in sectional shape, but may be
also formed in an elliptical sectional shape. The left bumper core
3 as seen from the inside of the bumper fascia 2 is symmetrical to
the right bumper core 3 and is identical in structure. The bumper
cores 3 are secured to the bumper fascia 2 by conventional means
such as adhering or gluing. As the bumper cores are sectional, they
can be asymmetrically designed for specific applications.
[0043] As shown in FIG. 3, the inclination angle .theta. of the
sidewall 7 to the perpendicular line of the surface wall 8 is
preferred to be 0 to 50 degrees in order to obtain a sufficient
impact absorbing effect. The concave ribs 10a, 10b are conical
shaped being wider in diameter at the surface wall 8 or rear wall
9, as opposed to the center at the fusing portion 10c. Such conical
or cone shape may have the appearance of a cup and have a flattened
portion instead of a point at the smaller diameter.
[0044] In the preferred embodiment, the angular dimension of the
diameter contracting angle .alpha. is 5 to 30 degrees, and the
diameter .beta. of the opening end is 10 to 40 mm. The cone shape
can encompass a sharp cone nose or have a flush nose end. By
forming the concave ribs 10a, 10b in this range to compose the
buffer portion, it is known by experimentation that the highest
shock absorbing effect of the bumper cores 3 is obtained against
the impact acting on the bumper 1. It is within the scope of the
invention that the concave ribs 10a, 10b may be also formed in
other shapes.
[0045] The bumper cores 3 are composed of thermoplastic resin of
which modulus of flexural elasticity is 10000 kg/cm.sup.2 to 40000
kg/cm.sup.2, and the overall mean wall thickness is 0.5 mm to 4.0
mm, and the product of modulus of flexural elasticity and mean wall
thickness is 1000 kg/cm to 10000 kg/cm. The modulus of flexural
elasticity is the value established by testing according to the
Japan Industrial Standard (JIS) K 7113. This testing methodology
uses specimen type No. 2 and is measured at a pulling rate of 2
mm/min.
[0046] Examples of thermoplastic resin for composing the bumper
cores 3 include high density polyethylene resin, polypropylene
resin, polyamide resin, polyethylene terephthalate resin,
polybutylene terephthalate resin, polycarbonate resin,
acrylonitrile butadiene styrene resin (ABS resin), acrylonitrile
styrene resin (AS resin), acrylonitrile acrylic rubber styrene
copolymer (AAS resin), polyphenylene ether resin (PPO resin), and
their blends.
[0047] FIG. 4 shows a second embodiment of the right bumper core 3.
The left bumper core 3 is symmetrical in shape, but is identical in
structure. In the bumper core 3, a rib 10 is formed from a surface
wall 8, and is fused to a rear wall 9, and a buffer portion is
composed by the rib 10 which links the surface wall 8 and rear wall
9. There is no fused portion 10c as described in the first
embodiment.
[0048] FIG. 5, FIG. 6, and FIG. 7 show other examples (third to
fifth embodiments) of the bumper cores 3. In FIG. 5 to FIG. 7, the
right bumper core 3 is shown, but the left bumper core 3 is
symmetrical in shape, and is identical in structure.
[0049] In the bumper core 3 shown in FIG. 5 (third embodiment), the
rib 10 for linking a surface wall 8 and a rear wall 9 is formed as
a plate in the hollow part 6. In this manner the rib 10 is termed
an "inner rib" extending from the rear wall 9 to the surface wall
8. In the bumper core 3 shown in FIG. 6 (fourth embodiment), a
plate 11 for reinforcing the inner rib is buried and the rib 10 is
formed to provide a stronger reinforcing member between the surface
wall 8 and a rear wall 9. The buried plate 11 is a thicker
structure and provides greater reinforcing strength for the inner
rib 10. In this embodiment the inner rib is not a concave structure
but is as illustrated in the figures.
[0050] The bumper core 3 shown in FIG. 7 (fifth embodiment) is a
hollow double wall structure without the rib for linking between
surface wall 8 and rear wall 9. The inclination angle .theta.' of
the sidewall 7 to the perpendicular line of the surface wall 8 is
preferred to be 0 to 50 degrees in order to obtain a sufficient
impact absorbing effect.
[0051] FIG. 8 to FIG. 11 relates to a sixth embodiment. FIG. 8 is a
front view of the bumper core as seen from the rear wall side. FIG.
9 is a sectional view along line Y-Y in FIG. 8. FIG. 10 is a
sectional view along line Z-Z in FIG. 8, and FIG. 11 is a
perspective view of portions of FIG. 8.
[0052] The bumper core 3 of the sixth embodiment, the shape of the
rib 10 is the same as the concave ribs 10a, 10b shown in FIG. 3. In
part of the sidewall of the bumper core 3, one or more rib portions
12 also called sidewall ribs are recessed in the hollow portion 6
and are formed at specified intervals. The sidewall ribs 12 are
semicircular, and are contracted in diameter in the hollow part
direction from the opening end of the surface wall 8 or rear wall 9
of the bumper core 3, and the diameter contracting angle x is 5 to
30 degrees, and the radius y of the opening end is 5 to 20 mm.
[0053] As shown by rib portion 12, a plate or fusing portion 13 is
formed nearly in the middle between the surface wall 8 and rear
wall 9 in order to enhance the reinforcing effect. By forming the
rib portion 12 with the diameter contracting angle x is 5 to 30
degrees, and the radius y of the opening end is 5 to 20 mm, it is
known by experimentation that the highest shock absorbing effect of
the bumper core 3 is obtained against impact acting on the bumper
1.
[0054] The multiple concave ribs 10a of the bumper core 3 of the
sixth embodiment are integrally linked by coupling ribs 14 that
join adjacent ribs together. The coupling rib 14 also called tie-up
rib is a longitudinal rib formed to extend in the direction of the
rear wall 9 from the surface wall 8. The coupling rib 14 is formed
like an inner rib with the longitudinal rib concealed in the hollow
part 6 as shown in FIG. 11. This inner coupling rib 14 is made by
integrating two walls of the parison into a plate by air pressure
after forming the concave portion from the surface wall 8 toward
the hollow portion 6 in the blow molding process. By using this
coupling or tie-up rib 14, the position and direction of the
concave ribs 10a can be held in a constant profile. As the shape
and profile of concave rib 10a is maintained by this coupling rib
14, the properties and characteristics of the bumper core are
consistent. In particular, from the viewpoint of buffering effect,
the coupling rib 14 is preferred to be formed integrally with the
concave ribs 10a at the surface wall 8 side as shown in FIG.
11.
[0055] Other forms of the coupling rib 14 for mutually linking
multiple concave ribs 10a, 10b, in other embodiments are shown in
FIG. 12 and FIG. 13.
[0056] In the embodiment shown in FIG. 12, the coupling rib 14 is
formed in a groove or notch from the surface wall 8 side, and a
plate 17 is formed from the bottom of the groove 16 disposed in the
direction to the rear wall 9 side. The plate 17 is comprised of two
walls pressed together by air and molded into a single plate,
wherein the dotted line represents the melt line. By forming the
coupling rib 14 in such shape, the strength and rigidity of the
bumper cores 3 are enhanced.
[0057] In the embodiment shown in FIG. 13, the coupling rib 14 is
formed in a V-shaped groove, and by forming in this shape, the
strength and rigidity of the bumper cores 3 are also enhanced.
[0058] The automobile bumper according to the invention is intended
to provide greater impact absorbing qualities from outside impact
forces. The invention has bumper cores interposed between the
bumper fascia and the car body at the inside right and left
positions, and the bumper cores are closed molded bodies formed in
a hollow double wall structure by blow molding of thermoplastic
resin as a molded body having a hollow part and having sidewalls
upright in the longitudinal direction of the bumper fascia, and are
therefore excellent in rigidity against impact and restoration
after deformation in spite of small space in the longitudinal
direction. Hence, even in a structure admitting only a bumper core
of small space in the longitudinal direction between the inside of
the bumper fascia and car body, such as the rear bumper, absorption
of impact from outside and safety can be enhanced.
[0059] The bumper cores of the bumper of the invention are composed
of thermoplastic resin of which modulus of flexural elasticity is
10000 kg/cm.sup.2 to 40000 kg/cm.sup.2, and the overall mean wall
thickness is 0.5 mm to 4.0 mm, and the product of modulus of
flexural elasticity and mean wall thickness is 1000 kg/cm to 10000
kg/cm, and therefore they are excellent in rigidity against impact
and restoration after deformation, and further by the structure
forming the ribs for linking between the surface wall and rear wall
of the bumper core, the rigidity against impact and restoration
after deformation are further enhanced.
[0060] The bumper cores of the bumper of the invention are closed
molded bodies having a buffer section composed of concave ribs for
linking between the surface wall corresponding to the inside of the
bumper fascia and the rear wall corresponding to the car body, or
part of the sidewall of the bumper cores is recessed to the hollow
part side to be formed into rib-like molded bodies, so that a
higher impact absorption and safety may be obtained.
[0061] In the bumper cores of the present invention, since the
coupling rib is formed to join plural adjacent concave ribs
mutually, the position and direction of the concave ribs can be
held in a constant profile in the event of collision. This enables
the bumper core to be positioned within the bumper fascia with the
optimal impact absorption in a specific direction. Selective
directional impact absorption can be accommodated by positioning
the bumper core in the regions likely to receive impact.
[0062] Furthermore, since plural rib portions are recessed to the
hollow portions and formed at specified intervals in the sidewall,
a high shock absorbing effect results.
[0063] Since other modifications and changes varied to fit
particular operating requirement, and environments will be apparent
to those skilled in the art, the invention is not considered
limited to the example chosen for purposes of disclosure, and
covers all changes and modifications which do not constitute
departures from the true spirit and scope at this invention.
[0064] Having thus described the invention, what is desired to be
protected by Letters Patent is presented in the subsequently
appended claims.
* * * * *