U.S. patent application number 09/730178 was filed with the patent office on 2002-06-06 for fuel tank.
Invention is credited to McGinnis, Kelly L., Stack, Gary Francis.
Application Number | 20020066737 09/730178 |
Document ID | / |
Family ID | 24934269 |
Filed Date | 2002-06-06 |
United States Patent
Application |
20020066737 |
Kind Code |
A1 |
Stack, Gary Francis ; et
al. |
June 6, 2002 |
Fuel tank
Abstract
A fuel tank for a vehicle includes a plastic tank shell having a
first half shell and a second half shell. The fuel tank also
includes a support structure having a honeycomb configuration
disposed between and connected to the first half shell and the
second half shell to provide support to the tank shell.
Inventors: |
Stack, Gary Francis;
(Fenton, MI) ; McGinnis, Kelly L.; (Fenton,
MI) |
Correspondence
Address: |
VINCENT A. CICHOSZ
DELPHI TECHNOLOGIES, INC.
Legal Staff
P.O. Box 5052, Mail Code: 480-414-420
Troy
MI
48007-5052
US
|
Family ID: |
24934269 |
Appl. No.: |
09/730178 |
Filed: |
December 5, 2000 |
Current U.S.
Class: |
220/564 ;
220/4.14 |
Current CPC
Class: |
B60K 15/077 20130101;
B60K 2015/0344 20130101 |
Class at
Publication: |
220/564 ;
220/4.14 |
International
Class: |
B65D 006/00; B65D
008/00; B65D 006/12 |
Claims
1. A fuel tank for a vehicle comprising: a plastic tank shell
having a first half shell and a second half shell; and a support
structure having a honeycomb configuration disposed between and
connected to said first half shell and said second half shell to
provide support to said tank shell.
2. A fuel tank as set forth in claim 1 wherein said support
structure is made of a plastic material.
3. A fuel tank as set forth in claim 1 wherein said plastic
material is a thermoformable plastic.
4. A fuel tank as set forth in claim 1 wherein said first half
shell has a base wall and a side wall extending generally
perpendicular to said base wall.
5. A fuel tank as set forth in claim 1 wherein said second half
shell has a base wall and a side wall extending generally
perpendicular to said base wall.
6. A fuel tank as set forth in claim 1 wherein said support
structure has a plurality of side walls extending axially and
generally perpendicular to said first half shell and said second
half shell.
7. A fuel tank as set forth in claim 6 wherein said support
structure has a plurality of cavities extending axially and formed
by said side walls.
8. A fuel tank as set forth in claim 7 wherein said cavities have a
closed cell configuration.
9. A fuel tank as set forth in claim 6 wherein said side walls are
welded to said first half shell.
10. A fuel tank as set forth in claim 6 wherein said side walls are
welded to said second half shell.
11. A fuel tank as set forth in claim 1 including a band disposed
over said tank shell.
12. A fuel tank for a vehicle comprising: a plastic tank shell
having a lower half shell and an upper half shell; and a plastic
support structure having a honeycomb configuration disposed between
and connected to said lower half shell and said upper half shell to
provide support to said tank shell.
13. A fuel tank as set forth in claim 12 wherein said support
structure has a plurality of side walls extending axially and
generally perpendicular to said lower half shell and said upper
half shell.
14. A fuel tank as set forth in claim 13 wherein said side walls
form a plurality of cavities extending axially.
15. A fuel tank as set forth in claim 14 wherein said cavities have
a closed cell configuration.
16. A fuel tank as set forth in claim 13 wherein said side walls
are welded to said lower half shell.
17. A fuel tank as set forth in claim 16 wherein said side walls
are welded to said upper half shell.
18. A fuel tank as set forth in claim 12 including a band disposed
over said tank shell.
19. A fuel tank as set forth in claim 18 wherein said band is made
of a metal material.
20. A fuel tank for a vehicle comprising: a plastic tank shell
having a lower half shell and an upper half shell, wherein said
lower half shell has a lower base wall and a lower side wall
extending generally perpendicular to said lower base wall, wherein
said upper half shell has an upper base wall and an upper side wall
extending generally perpendicular to said upper base wall; and a
plastic support structure disposed between and connected to said
lower half shell and said upper half shell to provide support to
said tank shell, wherein said support structure has a plurality of
support side walls extending axially and generally perpendicular to
said lower base wall and said upper base wall, said side walls
being welded to said lower base wall and said upper base wall.
Description
TECHNICAL FIELD
[0001] The present invention relates generally to fuel tanks for
vehicles and, more particularly, to a plastic fuel tank for a
vehicle.
BACKGROUND OF THE INVENTION
[0002] It is known to provide a fuel tank such as a metal or
plastic fuel tank in a vehicle to hold fuel to be used by an engine
of the vehicle. Typically, the fuel tank has a shell with a tank
opening and a unit installed into the tank via the tank opening. An
access cover is placed over the tank opening and is used to
assemble and service the fuel pump and other related components.
The access cover must be sealed to prevent fuel leakage and
evaporative emissions. However, these fuel tanks may not be
acceptable to meet zero evaporative emissions.
[0003] One commercial approach to resolve these concerns is to
provide a non-vented fuel system to meet zero evaporative
emissions. However, this requires a fuel tank to withstand higher
pressures and vacuum levels than in the past.
[0004] Therefore, it is desirable to provide a plastic fuel tank
for a vehicle that has can withstand higher pressure and vacuum
levels than current tanks. It is also desirable to provide an
internal support structure to support upper and lower half shells
of plastic fuel tank.
SUMMARY OF THE INVENTION
[0005] It is, therefore, one object of the present invention to
provide a new plastic fuel tank for a vehicle.
[0006] It is another object of the present invention to provide a
plastic fuel tank that has a support structure disposed inside the
fuel tank.
[0007] To achieve the foregoing objects, the present invention is a
fuel tank for a vehicle including a plastic tank shell having a
first half shell and a second half shell. The fuel tank also
include a support structure having a honeycomb configuration
disposed between and connected to the first half shell and the
second half shell to provide support to the tank shell.
[0008] One advantage of the present invention is that a new plastic
fuel tank is provided for a vehicle. Another advantage of the
present invention is that the plastic fuel tank is able to
withstand much higher pressure and vacuum levels than conventional
plastic fuel tanks. Yet another advantage of the present invention
is that the plastic fuel tank incorporates an internal support
structure to improve tank durability under pressure and vacuum.
Still another advantage of the present invention is that the
plastic fuel tank meets zero evaporative emissions requirements
with a vacuum system. A further advantage of the present invention
is that the plastic fuel tank allows thinner walls to be used than
in conventional plastic fuel tanks and all components can be easily
mounted inside the fuel tank. Yet a further advantage of the
present invention is that the plastic fuel tank uses conventional
manufacturing processes. Still a further advantage of the present
invention is that the plastic fuel tank incorporates an internal
support structure to provide a strong plastic fuel tank at a lower
cost than a metal fuel tank.
[0009] Other objects, features, and advantages of the present
invention will be readily appreciated, as the same becomes better
understood, after reading the subsequent description taken in
conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is an exploded perspective view of a fuel tank,
according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0011] Referring to the drawings and in particular FIG. 1, one
embodiment of a fuel tank 10, according to the present invention,
is shown for a vehicle (not shown). The fuel tank 10 includes a
tank shell, generally indicated at 12. In the embodiment
illustrated, the tank shell 12 is of a generally rectangular type.
The tank shell 12 includes a first or lower half shell 14 and a
second or upper half shell 16. The lower half shell 14 has a base
wall 18 and a side wall 20 around a periphery of the base wall 18
and extending generally perpendicular thereto. The side wall 20 may
have a flange (not shown) extending outwardly and generally
perpendicular thereto. The upper half shell 16 has a base wall 24
and a side wall 26 around a periphery of the base wall 24 and
extending generally perpendicular thereto. The side wall 26 may
have a flange (not shown) extending outwardly and generally
perpendicular thereto. The flanges 22 of the lower half shell 14
and upper half shell 16, respectively, are joined together by
suitable means such as by thermoforming, compression molding, or
friction welding. The lower half shell 14 and upper half shell 16
are made of a plastic material such as a thermoformable
plastic.
[0012] Referring again to FIG. 1, the fuel tank 10 includes an
internal support structure, generally indicated at 30, disposed
between and attached to the lower half shell 14 and upper half
shell 16. In one embodiment, the support structure 30 is honeycomb
shaped with a plurality of cavities 32 that are of a generally
cylindrical and pentagonal cross-sectional shaped. The support
structure 30 has a plurality of side walls 32 extending axially
between the base walls 18 and 24 and extending generally
perpendicular thereto. The side walls 32 form the cavities 32 in a
closed cell configuration. The side walls 32 are joined to the
lower half shell 14 and upper half shell 16, respectively, by
suitable means such as welding. The support structure 30 is made of
a plastic material such as a thermoformable plastic. It should be
appreciated that the support structure 30 may have a suitable
honeycomb shape other than pentagonal such as triangular,
elliptical, rectangular, or circular shaped. It should also be
appreciated that the support structure 30 is integral, unitary, and
one-piece.
[0013] In manufacturing the fuel tank 10, several conventional
processes may be used. Preferably, the lower half shell 14 and
upper half shell 16 are formed by a conventional vacuum forming
process. Vacuum formed plastic fuel tank 10 is made of multi-layer
extruded sheets and vacuum formed into two shells, one to make the
upper half shell 16 of the fuel tank 10 and the other for the lower
half shell 14 of the fuel tank 10. The support structure 30 is
formed by extrusion or injection molding. The support structure 30
is placed between the lower half shell 14 and upper half shell 16
of the fuel tank 10. The support structure 30 is welded to the
lower half shell 14 and the upper half shell 16 to support pressure
loads. The upper half shell 16 is also welded to the lower half
shell 14 in a mold, right after vacuum forming, creating a bond
line where the two shell halves are fused. A circumferential steel
band 40 may be added to the outside of the tank shell 12 to support
the hoop stresses obtained from pressure. It should be appreciated
that the support provided by the support structure 30 in the tank
shell 12 with 6.0 millimeters (mm) walls will support up to eight
pounds per square inch (8 psi) in vacuum at 80.degree. C. and up to
four pounds per square inch (4 psi) pressure at 80.degree. C. as
along as the plastic fuel tank 10 has no more than 100 mm of span
in any direction unsupported. It should also be appreciated that if
the tank wall is a different thickness, the span to thickness ratio
should be approximately 17 to 1. It should further be appreciated
that, for manufacturing purposes, there must be a 2 mm to 10 mm gap
between the side walls 20, 26 of the fuel tank 10 and the support
structure 30.
[0014] The present invention has been described in an illustrative
manner. 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.
[0015] Many modifications and variations of the present invention
are possible in light of the above teachings. Therefore, within the
scope of the appended claims, the present invention may be
practiced other than as specifically described.
* * * * *