Note: Descriptions are shown in the official language in which they were submitted.
CA 02233001 2006-02-08
-1-
"AUTOMOBILE"
Technical Field
The present invention relates to automobiles, and more
particularly, to a lightweight, passenger, self propelled vehicle, with
s improved structural and body characteristics.
Background Art
The conventional automobile often carrying a single driver-
passenger, weighs on the average between 1000 and 1200 kg. and transports
an average person of 70 kg. It is well settled that the conventional
to automobile is highly inefficient, particularly in a city environment in
view
of the amount of energy in the form of fuel required to move such a vehicle
and the resultant pollution. No matter how much research is done on engine
efficiency, inefficiencies will remain as long as the automobile has the mass
referred to above.
is In addition, conventional automobiles have a drag coefficient of
Cd = 0.38 or more. For highway driving, the drag coefficient increases the
power requirements of the vehicle. Thus relatively powerful engines are
required to overcome the mass and drag coefficient. Such engines add to the
overall mass of the vehicle. Fuel consumption is rarely below 7 liters per
20 100 kilometers.
One of the problems with lightweight vehicles is the lack of
stability at higher speed. In order to attain a mass of less than 500 kg. the
resulting vehicle would be fragile and somewhat unstable at speed of
100 km. or more, due to aerodynamic lift associated with most conventional
2s body shapes.
U.S. Patent No. 3,951,222, Fletcher, issued Apr. 20, 1976, shows
a lightweight car in the form of a reverse airfoil. Although the aerodynamic
lift associated with the automobile shown in this patent is
~, CA 02233001 1998-03-24
L;~
reversed, the automobile in this patent would be
subject to lateral instability.
Disclosure of the Invention
It is an aim of the present invention to
S provide a lightweight vehicle with low aerodynamic drag
coefficient to thereby reduce the power requirements.
AMENDED SHEET
CA 02233001 1998-03-24
WO 97/11874 - 2 - PCT/CA96/00637
It is a further aim of the present invention
to provide an inexpensive automobile construction pro-
viding reduced maintenance.
It is a further aim of the present invention
to provide an automobile with reduced drag coefficient
of Cd = 0.20 or lower and a mass of less than 450 kg. '
It is an aim of the present invention to
provide an automobile of low mass but having aero
dynamic features which render the automobile stable at
higher speeds.
It is a further aim of the present invention
to provide an automobile with relatively low fuel con-
sumption.
It is a further aim of the present invention
to provide a vehicle where the engine and transmission
is concentrated in the center of the vehicle providing
a low polar moment and improve vehicle handling.
It is a further aim of the present invention
to provide an automobile with improved safety for the
driver and passengers.
A construction in accordance with the pre-
sent invention comprises an automobile having a chassis
and an outer cladding in the form of an airfoil with a
top wall forming the pressure surface, the bottom wall
forming the suction surface, the front of the auto-
mobile forms the leading edge and the rear forms the
trailing edge. At least a spoiler is provided at one of
the front and rear portions of the automobile, the
spoiler being located at the bottom wall near one of
the leading edge and the trailing edge respectively.
The spoiler extends transversely of the automobile and
is spaced from the bottom wall to provide an air flow
passage therebetween and form a downward force on the
automobile.
In a more specific embodiment there is a
front spoiler and a rear spoiler such that the spoilers
provide a downward force on the automobile sufficient
to provide stability thereto at high speeds. The spoil-
CA 02233001 1998-03-24
WO 97/11874 - 3 - PCT/CA96/00637
ers also form the front and rear bumpers of the auto-
mobile.
In another aspect of the present invention
the automobile is provided with an engine located
centrally of the chassis and at the proximity of the
center of gravity.
In a more specific embodiment of the present
invention a pair of vertical stabilizer fins are pro-
vided at the trailing edge of the automobile and pro-
ject rearwardly in order to provide lateral stability
to the automobile and with an additional purpose of
locating the pressure center of the automobile aft of
the center of gravity of the automobile.
More specifically the present invention pro-
vides an automobile body with a drag coefficient of Cd
- 0.20 or lower. The total vehicle curb mass would be
less than 450 kg.
Still more specifically the automobile is
provided with a pair of bulkheads front and rear of the
engine and defining an inverted V, the bulkheads form-
ing backrests for oppositely disposed front and rear
seats of the automobile.
Thus the structure of the automobile in-
cludes back-to-back four passenger seats with the back
rests of the seats being integrated to the triangular
configuration of structural bulkheads. The drive train
is suspended from the apex of the structural bulkheads,
including the engine which is located at the level of
the floor. The floor is double clad including the bot-
tom wall and includes storage for the gas tank, and in
the event of conversion to an electrical motor, storage
of the batteries.
Brief Description of the Drawings
Having thus generally described the nature
of the invention, reference will now be made to the
accompanying drawings, showing by way of illustration,
a preferred embodiment thereof, and in which:
CA 02233001 1998-03-24
WO 97/11874 - 4 - PCT/CA96/00637
Fig. 1 is a vertical side elevation, partly
in cross section, showing the air flow around the body
of the vehicle;
Fig. 2 is a side elevation, partly schematic
and partly in cross-section, of the vehicle in accor
dance with the embodiment shown in Fig. 1 showing some
elements in dotted lines;
Fig. 2a is a perspective view of a detail of
the embodiment shown in Fig. 2;
Fig. 3 is a schematic top plan view, of the
vehicle shown in Figs. 1 and 2;
Fig. 4 is a fragmentary rear end elevation
of the embodiment shown in Figs. 1 and 2;
Fig. 5 is a fragmentary perspective view of
a detail of the present invention;
Fig. 6 is a fragmentary enlarged perspective
view of a further detail of the present invention;
Fig. 7 is a fragmentary enlarged vertical
cross-section of a further detail of the present inven
tion taken along lines 7-7 of Fig. 3;
Fig. 8 is a schematic diagram in perspective
showing a further characteristic of the present inven-
tion;
Fig. 9 is a fragmentary enlarged perspective
view of a further detail of the present invention; and
Fig. 10 is a fragmentary vertical cross sec-
tion taken along lines 10-10 of Fig. 3.
Modes For Carrying Out The Invention
Referring to Figs. 1, 2 and 3, an automobile
A is illustrated having a chassis C, a bottom clad wall
10 and a roof 12. The over all shape of the automobile
A is that of an inverted airfoil having a leading edge
14 and a trailing edge 16.
As shown in Fig. 1, the configuration of the
suction surface or clad bottom wall 10 and the pressure
surface or roof 12 provides a negative aerodynamic lift
at high. speeds pressing the automobile towards the
CA 02233001 2006-02-08
-5-
ground. This is enhanced by the spoilers 18 and 20 fore and aft of the
automobile body A.
Spoiler 18 is illustrated in FIG. 9. Spoiler 20, shown in FIG. 1, is
of similar construction. The spoiler 18 also serves as a bumper and extends
5 transversely of the chassis and is connected at its ends to fender 22 and to
fender 24 respectively. The spoiler 18 is spaced from bottom clad wall 10
and helps provide additional negative lift at the front of the vehicle. The
spoiler 20 provides a similar negative lift at the aft portion of the
automobile A. A central connecting member 26 mounted to the chassis C
t o provides support for the spoiler 18, and, along with the laterally spaced
fenders 22 and 24, guide the airflow underneath the automobile A.
The spoilers 18 and 20 each have a horizontal component Ph at
the front and rear of the automobile acting in opposite direction. When the
airflow passes by the spoilers the Ph component of each spoiler 18 and 20
15 cancels the other. In fact the forces are acting on the automobile
structure to
stretch it out. Vertical components P,, press the car downwardly towards the
ground, increasing the stability. The downward forces on the automobile
increase the rolling resistance but this is by far compensated by the gains in
stability.
2o As shown in FIG. 2, the engine 28 is placed centrally of the
automobile A, in the lower part thereof. The engine 28 may be of the type
described in U.S. Pat. No. 4,727,794, issued March 1, 1988 to Marek
Kmicikiewicz. Torque reaction pads 29 are provided to resist the torque
developed by the engine 28. The drive train also includes a clutch housing
2s 30 which can be a standard single disc dry clutch. An inter-axle
differential
32 is superimposed with a split power CVT transmission 34 of the type
described in U.S. Pat. No. 5,121,936 issued June 16, 1992 to Ben Cowan.
The drive train unit, including the above mentioned engine 28,
clutch housing 30, differential 32
CA 02233001 1998-03-24
WO 97/11874 - 6 - PCT/CA96/00637
and transmission 34 is suspended from the apex of two
bulkhead 36 and 38 which foam a structural triangle as
shown in Figs. 2 and 5.
The bulkheads 36 and 38 also form the back
rests of the seat sets 60 and 62. Panels 37 are
removable, for access to the space between the
bulkheads 36 and 38 where the engine transmission and
other equipment are situated. It is noted that the
engine and transmission could be removed in less than
30 minutes. Head rests 25 are illustrated at the top of
the seats 60a, 60b, 62a, and 62b, as shown in Figs. 2
and 3. A suspension system 40 suspends the drive train
from the apex of the bulkheads 36 and 38. The
suspension of the drive train allows for better
distribution of the loading forces on the chassis C.
Referring to Figs. 2, 3, 5, 6, and 7, there
is shown the chassis C which includes a double clad
floor with spaced-apart panels 10 and 11. There are two
longitudinal beams 42 and 44 which extend from the
front cross beam 46 to the rear cross beam 48. The
beams 46 and 48 are U-shaped stampings of aluminum and
have outwardly extending flanges 55 for the purposes of
bonding, and spot welding or riveting. The cross-
section of a typical longitudinal beam 42 is shown in
Fig. 6, cross or lateral beams 46, 48, 50 and 52 extend
between beams 42 and 44. Beam extensions 46L, 46R, 48L,
48R, 50L and 50R, 52L and 52R, are provided outboard of
beams 42 and 44 corresponding to the beams 46, 48, 50
and 52. All of the flanges 55 of the beams are bonded,
riveted or spot-welded to the cladding as represented,
for instance, by panels 10 and 11.
A tunnel having a front segment 56 and a
rear section 58 extends longitudinally and centrally of
the chassis C and within the passenger cabin dividing
the two sets of seats 60 and 62, into seats 60a, 60b,
62a and 62b respectively, as shown in Figs. 3 and 5.
These tunnel sections 56 and 58, in addition to
providing space for the power transmission elements,
CA 02233001 2006-02-08
i
-7_
provide structural strength to the automobile for support of the front and
rear bulkheads during crashes. The housings of tunnel sections 56 and 58
also provide additional stiffness to the overall structure of the chassis C.
The power transmission is provided to rear and front axles by
s cogged belts 64 and 66 extending in tunnel sections 56 and 58 respectively.
These cogged belts 64 and 66 may be of the type referred to as Uniroyal
HTD-II synchronous belt drive system, as described in a Uniroyal
publication entitled "PowerTrain", October 1985, or the PowerGrip TM HTD
belt system produced by The Gates Rubber Company and described in
Io Gates Industrial Belt Products/List Prices, January 2, 1990, No. 19996-000.
The inter-axle differential 32 provides a torque split at the drive belts 64
and 66. The rate of torque split depends on the load distribution between
front and rear axles, the height of the center of gravity of the automobile
and the mode of driving, that is mainly city or highway. The cogged belt 66,
15 as shown schematically in FIG. 2a, is in a mobius curve mode and twisted
to transmit torque from the vertical axis sprockets 33 of the inter-axle
differential 32 to the horizontal axis of the final drive differential. Belt
64
has a similar configuration. This arrangement is an efficient cost-effective
noise and vibration reducing drive system for lightweight vehicles.
2o The gas tank 68 is located under the right rear passenger seat 62b
and inboard of the right longitudinal beam member 44. The tank 68 is of 15
to 21 liter capacity and is thus protected from both side and rear impacts
and provides the automobile with 500 to 700 kilometer range.
It is noted that the clad floor 10 may be provided with an opening
25 below the drive train for access thereto.
CA 02233001 1998-03-24
WO 97/11874 - 8 - PCT/CA96/00637
The upper floor panel 11 may be provided
with stiffening beads and openings to give access to
some systems located in the double floor space. As
indicated previously, the double floor concept allows
for storage of batteries in the event of conversion to
an electric drive.
The steering column and instrument cluster
70 is adjustable in height and distance since the seats
60 are fixed. Similarly, the pedal cluster (not shown)
is adjustable horizontally to compensate for different
leg lengths. Since these two clusters, that is, the
steering column and instrument cluster 70 and the pedal
cluster, are independently adjustable relative to the
fixed seat 60a, it is possible to obtain a better driv-
ing position for different persons, including those
having shorter arms and longer legs, and vice versa.
An air intake 72 is provided at the front of
the automobile C, as shown in Figs. 2 and 3. The air
follows a ventilation duct to the engine 28 in order to
provide cooling air for the engine. The air intake 72
is located at the stagnation point at the leading edge
14, aerodynamically, on the automobile A where there is
the highest possible static pressure developed. The air
outlet 74 is in the form of tangentially oriented slots
at the aft portion of the automobile A where the veloc
ity of air is high and thus the negative pressure draw
ing the air from the exit is high. It is noted that a
fan will be provided in the air outlet 74 to increase
the negative pressure within the ventilation system for
the engine.
As shown in Figs. 7 and 10, an air passage
76 associated with the air duct 74 provides a passage
for the air through the transverse beam 50 to the
engine 28.
Vertical fender stabilizers 78, which serve
to provide lateral stability, are located on either
side of the automobile A, and also help to offset the
pressure center toward the rear (Fig. 4). This provides
CA 02233001 1998-03-24
WO 97/11874 - 9 - PCT/CA96/00637
correctional moment at high speeds during the loss of
traction at all four wheels. A roll-over bar 82, as
shown in Figs. 3 and 4, is provided centrally of the
automobile A and is supported by posts 84 to link~the
roll-over bar 82 with the longitudinal members 42 and
44 respectively. It is noted that the roll-over bar 82,
as shown in Fig. 4, has a greater dimension at the belt
height of the automobile than in the roof portion in
order to protect against sideways impact.
Fig. 8 represents the roof structure support
construction which includes pillars 86 and 88 which
cross each other and are supported at the belt line.
Braces 90a and 90b represent the windshield and door
braces.
There are bulkheads 92 at the front and rear
of the automobile A over the lateral beams 46 and 48 as
shown in Figs. 3 and 5. These bulkheads represent the
construction split lines of the automobile and are
designed to contain the crash energy without serious
deformation of the passenger cabin.
The portions fore of bulkhead 92 and aft of
bulkhead 94 are crumble zones. Transversal leaf
spring 96 is provided in bulkhead 92 to supplement the
suspension system. As shown in Fig. 10 suspension link
rods 98 and 100 are connected to the leaf spring 96
within the housing of bulkhead 92.
