FIELD OF INVENTION
This invention relates to an improved pedestrian protection absorber integrated
with air dam for vehicle. The absorber is disposed at the bottom part of the
vehicle to absorb the impact during pedestrian impact. The present invention
comprising of a three walled structure integrally molded to base surface of the
vehicle, which acts as an air dam by reducing air drag resistance. Further,
outlet of the three-walled air dam structure facilitates radiator cooling. Thus,
the instant invention constitutes single piece resin based lower leg pedestrian
absorber with integrated functionality of air-dam, air circulation and protection
of engine cooling system.
BACKGROUNDIPRIOR ART OF THE INVENTION
As it is known, the front under body cover is provided to protect the engine
room from foreign objects like stones, dust, water, etc. that ingress into the
engine room from bottom. In some vehicles it serves the purpose of an
Absorber from the viewpoint of pedestrian safety.
In vehicles, the front air dam (spoiler) is provided beneath the front bumper to
guide the airflow underneath the vehicle thereby reducing the aerodynamic
drag. Conventionally in the passenger cars the air dam is either a separate part
(plastic/ rubber/ composite) fitted to the bumper provided under lower cross
member connected to under cover which is Type-1 or integrated with the
bumper which is Type-2.
The disadvantage of separate Air Dam is the additional cost due to separate
child part and additional assembly time. Further due to complete coverage of
engine underbody, efficient air circulation is difficult.
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Reference may be made to the following prior arts:-
JP 2000177654A:- It comprises of downwardly projected air dam parts 10a,
12a run in the car width direction are formed on an undercover 10 disposed at
the central part of the bottom part of a car engine in the car width direction
and fender protectors 12 disposed at both the sides of the undercover 10 in the
car- width direction, respectively. At the vicinity of the air dam parts 10a, 12a,
the side end edge parts lob, 12b of the undercover 10 and the fender protector
12 are installed on a car body. The side end edge part 10d of the air dam part
10a of the undercover 10 is provided with an installing arm part 14 extended to
the fender protector 12.; A downwardly projected air dam part 14a run in the
car width direction is formed on the installing arm part 14. The tip of the
installing arm part 14 is installed on the side end edge part 12d of the air dam
part 12a of the fender protector 12.
Thus, it discloses an undercover integrated with the air dam.
US 6997490B2:- An integrated one-piece polymeric molded componeni'
includes an energy-absorbing section, a fascia-supporting beam section, and a
plurality of connecting section connecting the energy-absorbing and fasciasupporting
beam sections. The energy-absorbing section engages a front of a
bumper beam and includes crush boxes configured to absorb impact energy
during a vehicle crash. The connecting sections are strong enough to hold the,
energy-absorbing section and the fascia-supporting beam section together
during assembly of the one-piece component onto a vehicle, but are flexible to
allow collapse of the energy-absorbing section during a vehicle crash without
damaging the fascia-supporting beam section. The beam section is channelshaped
and extends cross-car generally between headlamps of the vehicle, for
providing added support structure to a front-end of the vehicle.; The beam
section includes air-redirecting ridges for optimal air flow and integral clips for
wire management.
Thus, it relates to an integrated one-piece polymeric molded component , which
includes an energy-absorbing section, a fascia-supporting beam section, and a
plurality of connecting section connecting the energy-absorbing and fasciai
supporting beam sections where air dams are into close engagement with a
rear surface of the fascia. However, the air dam, in this case is used to direct
the inlet air.
Hence, the present invention is introduced to add aerodynamic functionality to
the pedestrian absorber by the integration of Air Dam. It is superior in
versatility as it reduces the cost & additional mountings. Further, it enhances
the. cooling efficiency, air circulation and control of leg kinematics.
SUMMARY OF THE INVENTION I
The present invention comprising of air dam integrated to pedestrian protection
absorber. The pedestrian protection absorber provides stiffness to the lower
part of the front bumper during a pedestrian impact and cover the aft part of
the vehicle from bottom. A three walled open structure (air dam) is integrated
to the pedestrian absorber which serves the purpose of guiding the incoming 4
air flow to underneath the vehicle thereby reducing the air drag. The position of
air dam is directly below or rearward that of the radiator assembly allowing the
drain holes given in the air dam to serve as an outlet to cooling air coming to
the radiator. These exits as well serve the purpose of draining out water, mud;
pebbles, etc. that may get accumulated during normal running of the vehicle.
The pedestrian absorber has the provision to mount the shroud system which
helps in sealing the air flow and redirecting it to the condenser for efficient
radiator system cooling.
STATEMENT OF INVENTION
According to this invention, there is provided an improved pedestrian
protection absorber integrated with air dam for vehicle comprising of air dam
integrated to pedestrian absorber, wherein said air dam comprising of a walled
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structure having a base wall provided between front wall and back wall open
towards top face of the absorber comprising of sequential bending zones for
controlling leg kinematics.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
*
Further objects and advantages of this invention will be more apparent from
the ensuing description when read in conjunction with the accompanying
drawings and wherein:
Fig. 1: shows pedestrian protection absorber.
Fig. 2 shows: bottom view showing front bumper, air dam & pedestrian"
absorber.
Fig. 3 shows: exploded view of conventional bumper system having pedestrian
absorber (Type - 1).
Fig. 4 shows: conventional bumper system 5pe- 1.
Fig: 5 shows: section A-A conventional bumper with air dam (separate part)
(SP1) ~
Fig. 6 shows conventional bumper air-dam integrated (Type -2).
Fig. 7 shows: conventional bumper system (Type-2).
Fig. 8 shows: Section B-B air dam integrated bumper (Type-2).
Fig. 9 shows: exploded view of bumper system having air dam integrated
pedestrian absorber.
Fig. 10 shows: view showing drain holes of air dam integrated pedestrian.
Fig. 11 shows: rear view showing the drain holes of air dam integrated.
Fig. 12 shows Section C-C air dam integrated absorber & front bumper.
Fig. 13 shows C1 showing the cross section of pedestrian absorber with the
integrated air dam.
Fig. 14 shows: detail C 1- 1: 'showing the detail structure of air dam.
Fig. 15 shows: basic section of pedestrian absorber showing the bending
Fig; 16 shows: shroud system.
DETAIL DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE
ACCOMPANYING DRAWINGS:
As it is known, the front under body cover is provided to protect the engine
room from foreign objects like stones, dust, water, etc. that ingress into the
engine room from bottom. In some vehicles it serves the purpose of an
Absorber (A) (Fig. 1) from the viewpoint of pedestrian safety.
In vehicles, the front air dam (1) (spoiler) is provided beneath the front bumper
(2) to guide the airflow underneath the vehicle thereby reducing the
Aerodynamic drag. Conventionally in the passenger cars the air dam is either a
separate part (plastic/ rubber/ composite) fitted to the bumper provided under:
lower cross member connected to under cover (U) which is Type-1 as shown in
Fig.2, Fig.3, Fig.4 and Fig.5 or integrated with the bumper which is Type-:!
(Fig.6, Fig.7 and Fig.8).
The disadvantage of separate Air Dam is the additional cost due to separate
child part and additional assembly time. F'urther due to complete coverage of
engine underbody, efficient air circulation is difficult.
Hence, the present invention is directed to an improved pedestrian protection
absorber integrated with air dam for automobile or motor vehicle which is
capable of serving the combined purpose of pedestrian protection absorber,
undercover, air-dam & controlled air circulation. It is resin based single piece
part covering the front bottom portion of the vehicle as shown in fig. 9
indicating pedestrian absorber with integrated air dam (1) and bumper front
(2) w
It basically serves the purpose of energy absorber during an impact with the
pedestrian and thus helps in improving the leg kinematics required for the
pedestrian protection performance, as shown in Fig.15. The structure of the
pedestrian absorber has sequential bending zones as described in Fig.15,
wherein leg kinematics is controlled by the progressive bending of the
structure.
Also the absorber serves the purpose of undercover which protects the engine
compartment from ingress of foreign matter like water, mud, dirt, pebbles, etc.
into the engine room.
Now, reference may be made to fig. 12 - 14.
Air dam structure (A3 is integrally molded with the absorber (B') is disposed
under lower cross member (CL) for aerodynamic performance and for gradual
ene.rgy absorption of the absorber by providing bending zones 6. Air dam is a
three walled Vshaped structure (3, 4, 5) comprising of front wall (7), back wall
(4) and bas wall (5) opened towards the top face 2 of the absorber which runs
throughout the width of the vehicle. The depth of the structure is limited by the
ground clearance, ease of manufacturing and the drag coefficient values. The
notch (N) in the base wall (5), as shown in Fig.14, helps in better energy
absorption on impact with a pedestrian and adds novelty to the present
invention. The air dam structure of the present invention is provided with a
plurality of drain holes 10 which play an important role in circulating the
cooling air across the radiator assembly. The drain outlets (d) are also
indicated in fig. 10 and 11. The location of the air dam along the vehicle length
direction is therefore of prime importance. If air-dam is placed before the
radiator system, it results in loss of cooling air required by the radiator system
as major part of the air drains out of the engine compartment before reaching
the radiator. This results in decreased cooling performance of the radiator
system & hence the cabin cooling. However, in case the air dam is placed below
or rearwards of the radiator system location, the cooling air after passing
through the radiator system exits through the drain holes. This air circulation
ensures proper and efficient cooling performance of the radiator system. The
present invention ensures this phenomenon & hence adds value to the
ordinary pedestrian absorber. Apart from the above mentioned advantages, the
invention serves its intended purpose of lowering the air drag coming on to the
vehicle directly. This leads to the increase in fuel economy of the vehicle. The
structure of air dam improves the rigidity of the absorber & prevents warpage
which otherwise is a part quality problem owing to its low thickness.
Additionally a provision for shroud system (fig. 16) mounting is provided in the
absorber. The shroud system thus mounted seals the air past the radiator
system from the sides & redirects the air into the radiator system. This
ultimately leads to enhanced cooling of the radiator system.
Ribs 1 are provided throughout the part to impart stiffness. With the proper rib
pattern the part can be made with low thickness which ultimately leads to the
weight reduction & material saving and hence the cost. Also usage of integrated
air dam eliminates the need of air dam as a separate part. This
eliminates the need of a separate tool and hence the cost & inventory
associated with it.
Advantageous features of the present invention:
1) Elimination of a child part.
2) Tool saving: the tool for separate Air Dam is not required.
3) Material saving: the material required for separate Air Dam is eliminated &
hence can be commonised with the existing material of undercover/ pedestrian
absorber.
4) Cost saving: above mentioned factors lead to cost saving.
5) Inventory reduction: no need to maintain an extra inventory for a separate
Air Dam.
6) Saving of Assembly cost and assembly time.
Structure Nomenclature: (Fig. 13).
1 - Rib for stiffening (pedestrian protection)
2 - Base surface of pedestrian absorber
3 - Front wall of air dam
4 - Back wall of air dam
5 - Base wall of air dam
6 - Bending point during pedestrian impact
7 - Front bumper
8 - Radiator/ Condensor system
9 -'Crossmember
10 - Drain Hole on the back wall of air dam
11 - Mounting surface of pedestrian absorber to crossmember
12- Shroud
It is to be noted that the present invention is susceptible to modifications,
adaptations and changes by those skilled in the art. Such variant embodiments
employing the concepts and features of this invention are intended to be within
the scope of the present invention, which is further set forth under the
following claims:

WE CLAIM;
1. An improved pedestrian protection absorber integrated with air dam for
vehicle comprising of air dam integrated to pedestrian absorber, wherein
said air dam comprising of a walled structure having a base wall
provided between front wall and back wall open towards top face of the
absorber comprising of sequential bending zones for controlling leg
kinematics.
2. An improved pedestrian protection absorber integrated with air dam as
claimed in claim 1, wherein the base wall of air dam is provided with a
notch for better energy absorption on impact with pedestrian.
3. An improved pedestrian protection absorber integrated with air dam as
claimed in claim 1 or 2, wherein said air dam is provided with a plurality
of drain holes for circulation of cooling air across the radiator assembly.
4. An improved pedestrian protection absorber integrated with air dam as
claimed in any of the preceding claims, wherein the air dam is positioned
below or rear wards of the radiator system allowing the drain holes in the
air dam to serve as an outlet to cooling air for the radiator.
5. An improved pedestrian protection absorber integrated with air dam as
claimed in any of the preceding claims, wherein the absorber is provided
with a shroud system for sealing the air past the radiator system from
the sides and redirecting the air into the radiator system.
6. An improved pedestrian protection absorber integrated with air dam as
claimed in any of the preceding claims, wherein the absorber comprising
of a plurality of ribs to impart stiffness with a sequential bending zones
as shown in fig. 15.
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7. An improved pedestrian protection absorber integrated with air dam as
claimed in any of the preceding claims, wherein the resin based single
piece covering the front bottom portion of vehicle serves the combined
purpose of pedestrian protection absorber, under cover, air-dam and
controlled air circulation.
8. An improved pedestrian protection absorber integrated with air dam as
claimed in any of the preceding claims, wherein the absorber provides
stiffness to the lower part of the front bumper during pedestrian impact,
which covers the aft part of the vehicle from bottom and the air dam
serves the purpose of guiding the incoming air flow to underneath the
vehicle thereby reducing the air drag.
9. An improved pedestrian protection absorber integrated with air dam for
vehicle substantially as herein described with reference to the
accompanying drawings.