U.S. patent application number 10/734064 was filed with the patent office on 2005-06-16 for fuel tank assembly and method of assembly.
Invention is credited to Harris, Mark A., Knaggs, Richard A., Schulte, Kale S., Sekela, Ryan F., Vorenkamp, Erich J..
Application Number | 20050127078 10/734064 |
Document ID | / |
Family ID | 33541672 |
Filed Date | 2005-06-16 |
United States Patent
Application |
20050127078 |
Kind Code |
A1 |
Vorenkamp, Erich J. ; et
al. |
June 16, 2005 |
Fuel tank assembly and method of assembly
Abstract
The present invention relates to a fuel tank assembly and method
of securing a component in a fuel tank using induction welding. The
method generally includes the steps of placing a component in
contact with an inner surface of a fuel tank and inductively
welding the component to the inner surface of the fuel tank. The
fuel tank assembly generally includes a fuel tank having a wall
having a cavity, an inner surface, an outer surface, and an access
opening extending through the wall and communicating with the
cavity and a component inductively welded to said inner
surface.
Inventors: |
Vorenkamp, Erich J.;
(Pinckney, MI) ; Schulte, Kale S.; (Canton,
MI) ; Knaggs, Richard A.; (Ottawa Lake, MI) ;
Sekela, Ryan F.; (Ypsilanti Township, MI) ; Harris,
Mark A.; (Dexter, MI) |
Correspondence
Address: |
Douglas A. Mullen
Dickinson Wright PLLC
Suite 800
1901 L Street N.W.
Washington
DC
20036
US
|
Family ID: |
33541672 |
Appl. No.: |
10/734064 |
Filed: |
December 11, 2003 |
Current U.S.
Class: |
220/562 |
Current CPC
Class: |
B29C 66/71 20130101;
B29C 66/53245 20130101; B29C 65/362 20130101; B29C 66/71 20130101;
B60K 15/03177 20130101; B29C 66/863 20130101; B29C 65/3612
20130101; B29L 2031/7172 20130101; B29C 65/7847 20130101; B29C
66/112 20130101; B29C 66/7234 20130101; B29C 66/8161 20130101; B29C
66/131 20130101; B29C 66/61 20130101; B60K 2015/03453 20130101;
B29C 65/3676 20130101; B29C 66/71 20130101; B29C 66/8324 20130101;
B29C 66/71 20130101; B29K 2023/086 20130101; B29K 2023/00 20130101;
B29K 2077/00 20130101 |
Class at
Publication: |
220/562 |
International
Class: |
B60P 003/00 |
Claims
What is claimed is:
1. A method of attaching a component to a fuel tank having a wall
defining a tank cavity, an inner surface, an outer surface, and an
access opening extending through the wall, said method comprising:
placing the component in contact with the inner surface of the fuel
tank; and inductively welding the component to the inner surface of
the fuel tank.
2. The method of claim 1 wherein said step of inductively welding
the component further includes the steps of: energizing an emitter
coil to heat an induction receiver positioned in welding proximity
to a weld surface of the component to weld the component to the
inner surface; and deenergizing the induction coil after the
component is welded to the fuel tank.
3. The method of claim 1 wherein said step of placing the component
in contact with the inner surface of the fuel tank further includes
inserting the component through the access opening and offsetting
the component from the access opening.
4. The method of claim 1 further including: gripping the component
with a holder; inserting the holder into the access opening; and
displacing the holder to a position offset from the access opening
before welding the component to the inner surface.
5. The method of claim 4 wherein one of the holder and component
include an induction receiver in welding proximity to a weld
surface of the component and wherein said step of induction welding
further includes: energizing an emitter coil to heat the induction
receiver coupled to the arm; and deenergizing the emitter coil
after the component is inductively welded to the inner surface of
the fuel tank.
6. The method of claim 1 further including the steps of: coupling
the component with a holder on an arm; inserting the component and
holder into the access opening defined by the fuel tank; and
manipulating the arm to position the component in contact with the
inner surface at a location offset from the access opening.
7. The method of claim 6 further including manipulating the arm to
remove the holder from the fuel tank after inductively welding the
component.
8. A fuel tank assembly comprising: a fuel tank having a wall
having a cavity, an inner surface, an outer surface, and an access
opening extending through said wall and communicating with said
cavity; and a component inductively welded to said inner
surface.
9. The fuel tank assembly of claim 8 wherein said component is
offset from said access opening.
10. The fuel tank assembly of claim 8 wherein said component
includes a weld surface and an induction receiver fixed to said
component in welding proximity to said weld surface.
11. The fuel tank assembly of claim 8 wherein said induction
receiver includes an induction element integrally molded into said
component.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a fuel tank assembly and
method of securing a component in a fuel tank using induction
welding.
[0002] To save time and money and improve reliability,
manufacturers have been switching from metal fuel tanks to
thermoplastic fuel tanks. Thermoplastic fuel tanks generally have
lower material cost, lower manufacturing costs, increased
longevity, and are not subject to corrosion. One problem with
thermoplastic fuel tanks is that vapors may permeate through the
fuel tanks walls. To address this permeation problem and in view of
stricter emissions requirements, manufacturers have added
permeation resistant layers to fuel tanks and have attempted to
form fuel tanks out of as few pieces as possible.
[0003] While permeation resistant layers and blow molded fuel tanks
reduce permeation, problems still arise when components, such as
fill tubes, vent tubes, roll over valves, and vent valves, are
attached to the fuel tank. During attachment many manufacturers
drill holes through the wall of the fuel tank and weld the
component to the outside of the fuel tank. However, each opening
breaches the permeation resistant layer creating permeation
pathways.
[0004] As an alternative to creating separate holes for each
component, some manufacturers have attempted to move the attached
components inside the container using a single access hole. In this
approach, the component is secured to an interior surface readily
accessible from the access hole by directly welding the component
to the fuel tank using hot plate welding. In hot plate welding, a
plate disposed between the component and fuel tank is heated,
typically through resistive heating, until the component is capable
of being bonded to the fuel tank and the plate is displaced so that
the component may be placed into contact with the fuel tank to form
a bond area as the component and fuel tank cool. While this
approach reduces the number of potential permeation pathways, the
components generally are located approximately opposite the opening
within the fuel tank wall in a limited bonding area. The limited
bonding area typically includes a pump and fuel level sensor
assembly held by spring loaded rods against the bottom of the fuel
tank. Attempts to offset the component from the limited bonding
area have resulted in prolonged manufacturing cycle times due to
the delay in cooling the heating elements used to weld the
component to the tank wall before removal from the fuel tank.
Further, commonly used heating elements (such as hot plates) have
significant mass requiring excessive time to heat and cool the
heating element. In view of the above, a need exists for an
apparatus and method having faster cycle times for welding
components to an inner surface of a fuel tank and, preferably, for
an apparatus and method that permits the component to be secured to
a tank surface offset from the access opening.
SUMMARY OF THE INVENTION
[0005] The present invention relates to a fuel tank assembly and
method of securing a component in a fuel tank and to the fuel tank
wall using induction welding. The method generally includes the
steps of placing the component in contact with the inner surface of
the fuel tank and inductively welding the component to the inner
surface of the fuel tank. The step of inductively welding the
component may further include the steps of energizing an emitter
coil to heat an induction receiver positioned in welding proximity
to a weld surface of the component and deenergizing the induction
coil after the component is welded to the fuel tank. A holder may
grip the component and insert the component through the access
opening of the fuel tank. The component is generally displaced to a
position offset from the access opening, and placed in contact with
the inner surface before welding the component to the inner
surface. The arm generally manipulates the component to a position
in contact with the inner surface at a location offset from the
access opening.
[0006] The induction welding apparatus may include an emitter coil
and an induction receiver in welding proximity to the component to
induction weld a surface of the component to the fuel tank. The
method includes the steps of energizing the emitter coil to heat
the induction receiver coupled to the arm and deenergizing the
emitter coil after the component is inductively welded to the inner
surface of the fuel tank.
[0007] The fuel tank assembly may include a fuel tank having a wall
defining a cavity, an inner surface, an outer surface, and an
access opening extending through the wall and communicating with
the cavity and a component inductively welded to the inner surface.
The component is generally offset from the access opening and
includes a weld surface and an induction receiver fixed to said
component in welding proximity to the weld surface. The induction
receiver may be an element integrally molded into the
component.
[0008] Further scope of applicability of the present invention will
become apparent from the following detailed description, claims,
and drawings. However, it should be understood that the detailed
description and specific examples, while indicating preferred
embodiments of the invention, are given by way of illustration
only, since various changes and modifications within the spirit and
scope of the invention will become apparent to those skilled in the
art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The present invention will become more fully understood from
the detailed description given here below, the appended claims, and
the accompanying drawings in which:
[0010] FIG. 1 is a perspective view of a fuel tank;
[0011] FIG. 2 is a partial sectional view of the fuel tank in FIG.
1;
[0012] FIG. 3 is an enlarged sectional view of the fuel tank
wall;
[0013] FIG. 4 is a perspective view of the arm holding a component
within the fuel tank;
[0014] FIG. 5 is an enlarged sectional view of the bond area
between the component and fuel tank wall; and
[0015] FIG. 6 is an alternative enlarged sectional view of the bond
area between the component and fuel tank wall.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0016] A fuel tank assembly 10 constructed in accordance with the
illustrated embodiment is shown in FIGS. 1 and 2. The fuel tank
assembly 10 generally includes a fuel tank 20 defining an access
opening 24 and having an inner surface 26 to which a component 30
is induction welded. Induction welding the component 30 to the fuel
tank 20 allows the component to be displaced from the opening 24
without encountering many of the problems typically associated with
using a heating element to directly weld the component. Of
particular note is that the ability to place the component 30 where
desired in the fuel tank, including in areas offset from the access
opening 24 provides additional mounting locations, eliminates many
packaging concerns and may improve performance of certain
components. Induction welding also decreases cycle times by
reducing the wait time associated with heating and cooling of
conventional heating elements.
[0017] A variety of induction welding assemblies may be used to
secure components 30 to the fuel tank inner surface 26. A
representative assembly 49 is illustrated and described herein and
generally includes an articulating arm 50 having a holder 52
configured to releasably hold the component. The arm 50 is
controllable from the exterior of the tank through conventional
techniques to selectively position and induction weld components to
sections of the inner surface 26 that are offset from the limited
bonding area typically used with conventional welding techniques.
The method of the present invention generally includes the steps of
securing the component 30 to the holder 52 (FIG. 4), operating the
arm 50 to position the component in the fuel tank, induction
welding the component to the fuel tank 20, releasing the component
from the holder, and removing the arm and holder from the fuel
tank.
[0018] The fuel tank 20 includes a wall 22 defining a cavity 21. In
the illustrated embodiment, the fuel tank 20 is blow molded. The
wall 22 includes the inner surface 26, an outer surface 28, and a
permeation resistant layer 27 therebetween. The access opening 24
extends through the wall 22 and permits insertion and removal of
components 30 such as rollover valves, vapor vent valves, fuel
pumps, floats, and tubes held by clips. The layers forming the
inner and outer surfaces 26, 28 are typically formed from a polymer
material such as a polyolefin or other suitable thermoplastic
material. The permeation resistant layer 27 is generally formed
from a material having a suitable permeation rate such as nylon,
-ethylene vinyl alcohol copolymer (EVOH), liquid crystal polymers
(LCPs), or other permeation resistant materials. The fuel tank 20
may be formed in a variety of sizes, shapes, and configurations
depending on vehicle packaging, safety requirements and other
design objectives.
[0019] The component 30 includes a weld surface 32 (FIGS. 4 and 5)
formed out of a material that is suitable for welding to the inner
surface 26 of the fuel tank 20. The shape or configuration of the
weld surface 32 may be modified as needed to improve cycle times or
provide a more secure weld between the fuel tank 20 and component.
As with conventional induction welding assemblies, the assembly 49
of the present invention includes an emitter coil 40 and a receiver
41. The emitter coil 40 is located outside the fuel tank 20 and is
positionable within the proximity needed to the area of the tank
surface where the component 30 is to be secured. The receiver 41
may be separate from the holder and component, coupled to the
holder 52 or arm 30 (FIG. 5), or included in the component itself
(FIG. 6). By way of illustration, FIG. 6 shows an induction insert
34, such as a metal coil, fixed to or molded within the component
near the weld surface 32, to facilitate melting a portion of the
weld surface for bonding to the fuel tank 20. Alternatively,
induction particles (not shown) may be added to the component 30,
proximate the weld surface in place of the induction insert 34.
Integrally molding the induction insert 34 into the component 30 or
otherwise fixing the receiver to the component itself eliminates
the need to remove any heating element from the tank after welding,
thereby improving cycle times. As shown in FIG. 5 and noted above,
the component 30 may be made without induction insert 34 or
integrally molded induction particles such as by placing the
induction receiver 41, such as the illustrated induction element 56
on the holder 52 or arm 50 in close proximity to the weld surface
32.
[0020] In the illustrated embodiment, the arm 50 is a robotic arm
that articulates to position the component 30. A robotic arm allows
position feedback and can follow appropriate instructions in
placing the component. Any other device capable of placing the
component 30 in a position offset or displaced from the access
opening 24 may be used, such as a pick-n-place, fixed jig, or a
semi-flexible linkage. The type of arm 50 used may depend on the
position of the component. 30.
[0021] After the component 30 is attached to the inner surface 26
of the fuel tank 20 additional elements for operation of the
component may be assembled as well known in the art for fuel tanks.
Multiple components may be bonded to the fuel tank with induction
welding. In general, each attached component 30 is attached to the
fuel tank 20 at a bond area 14, when the weld surface 32 of the
component 30 melts to the inner surface 26 of the fuel tank.
[0022] The method of fuel tank assembly will now be described in
greater detail. In the illustrated embodiment, the component 30 is
secured within the holder 52 on the end of the arm 50. The holder
52 and the arm 50 may be of any configuration capable of holding
the component 30 and offsetting the component to the desired
position. As shown in FIG. 4, the arm 50 is an articulated arm with
the holder 52 at one end. The holder 52 includes an open-ended
cavity 60 configured to receive the component 30. As is shown in
FIGS. 5 and 6, the assembly 49 may include a vacuum passage 68
communicating with the cavity 60 as well as biasing elements, such
as the illustrated spring assembly 58. A vacuum source or other
means of actuation control, schematically illustrated by reference
numeral 62, communicates with the passage 68 and is selectively
energized to hold the component in the holder 52 while the
component 30 is displaced from the opening 24 to the desired
position within the fuel tank 20.
[0023] The arm 50 and holder 52 typically are inserted through the
access opening 24 and displaced to the proper position. As used in
this application, the phrases displaced or offset from the access
opening is intended to encompass movement of the component within
the tank anywhere outside the limited bonding area 12 illustrated
in FIG. 2. The limited bonding area 12 is the area on the inner
surface 26 opposite the access opening 24 and within view from the
access opening where conventional welding mechanisms could possibly
operate. By permitting efficient welding of components to areas
outside the limited bonding area 12 used in the prior art, the
present invention provides numerous mounting options not previously
available in the art and corresponding improvements in packaging
and performance. Further, displacement of or offsetting the
component from the opening allows the component 30 to be welded to
the same side of the fuel tank as the access opening 24, as
illustrated in FIG. 2.
[0024] After the arm 50, holder 52, and component 30 are inserted
through the opening and displaced to the proper position, the weld
surface 32 of the component 30 is placed in contact with the inner
surface 26 of the fuel tank 20. For example, the vacuum or other
actuation source may be de-energized to release the vacuum in the
chamber 51 whereupon the spring assembly 58 urges the component 30
toward the inner surface 26. With the component 30, specifically
the weld surface 32, in contact with the inner surface 26, the
component is ready to be welded to the fuel tank.
[0025] With the component 30 in place, the induction emitter coil
40 is placed in an opposing relationship to the receiver 41 with
the fuel tank wall 22 therebetween (FIGS. 5 and 6). The induction
emitter coil 40 may be any system or induction coil well known in
the art for use in induction welding. The induction emitter coil 40
may also be disposed in place before the component 30 is displaced
to the proper position. The actual position of the emitter coil 40
as well as the size, shape, and configuration may be varied as
needed to maximize efficiency of the induction welding. With the
emitter coil 40 in place, power is supplied to the induction
emitter coil to cause the induction receiver 41, such as the
induction insert 34, to increase in temperature. Power is supplied
to the emitter coil 40 until the induction insert 34 becomes heated
sufficiently for enough time to weld the component 30 to the fuel
tank. More specifically, the induction emitter coil 40 causes the
induction receiver 56 to increase in temperature so that the
thermoplastic material of the component 30 melts to create a bond
between the component 30 and inner surface 26 of the fuel tank 20.
Induction receivers 56 generally have less mass than, and therefore
heat and cool faster than, conventional heating elements, thereby
improving cycle times.
[0026] With the component 30 welded to the tank, power to the
induction emitter coil 40 is interrupted thereby allowing the
induction receiver 56, e.g., induction insert 34, to cool. If the
component 30 contains the induction insert, the holder 52 and arm
50 may be removed from the fuel tank once the bond area 14 hardens
enough to secure the component 30 on the fuel tank 20. If the
induction receiver 56 is located in the holder 52, the induction
receiver is allowed to cool sufficiently to prevent damage during
disengagement of the holder. Further, by using an induction
receiver instead of a heating element, power supply cords may be
eliminated resulting in a lightweight and controllable arm.
Furthermore, induction heating permits a significant heat flux to
be applied without the need for the relatively large, preheated
masses required for conventional resistive heating elements, thus
reducing the likelihood of damaging the fuel tank assembly during
insertion and removal of the apparatus.
[0027] The foregoing discussion discloses and describes an
exemplary embodiment of the present invention. One skilled in the
art will readily recognize from such discussion, and from the
accompanying drawings and claims that various changes,
modifications and variations can be made therein without departing
from the true spirit and fair scope of the invention as defined by
the following claims.
* * * * *