Note: Descriptions are shown in the official language in which they were submitted.
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INSULATED EDGE GUARD
EACKGROUND AND S ~ ~Y OF THE INVENTION
This invention relates to ornamental and protective
edge guards which are applied to the edges of body panels com-
monly used in automotive vehicle bodies, such as the vehicle
door edges.
In a typical automotive vehicle door edge guards are
applied to trailing edges of the vehicle's doors to protect
the door edges from damage which might be caused by striking
an object which may be present in a door's path when the door
is opened. It is very desirable for such door edge guards to
be made of bright metal, such as stainless steel, aluminum, or
bi-metal, due to the superior protective and ornamental charac-
teristics of such materials. Furthermore, the inherent
strength and resiliency of such metallic edge guards enable
them to be self-retaining on the doors. Correspondingly, it is
generally undesirable to use separate fasteners or adhesive in
securing edge guards to doors since they involve extra cost in
labor and materials. It is also generally undesirable to use
non-metallic edge guards, such as vinyl edge guards, since they
do not possess the superior protective, ornamental, and self-
retention characteristics of the bright metallic edge guards. In
connection with the use of self-retaining edge guards, it has
heretofore been recognized that the potential for paint scratching
and marring exists when the metallic edge guards are applied to
vehicle doors. Such paint scratching can lead to premature corro-
sion of the door edge metal. Some of applicant's own inventions
have addressed the paint scratching problem and provided
solutions. For example reference is made to U.S. patents
4,259,81~; 4,334,700; 4,316,3'48;4,338,148; 4,365,450; 4,377,056;
4,379,377; 4,379,376; and 4,387,860. Certain of these
patents disclose the use of plastic liners to insulate the
metallic edge guard from the door edge. From the standpoint
of ease of installation on a door edge, the most desirable
construction is to provide the liner as an integral laminate
to the metallic edge guard channel. In accordance
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wi~h procedures invented by applicant one way of providing this
construction is by laminating plastic film to sheet metal
material and then roll forming the laminate to the desired cross
sectional shape.
Several of the above mentioned patents disclose edge
guard constructions in which a portion of the insulating material
is visible on the exterior of the edge guard installed on the
vehicle door. For example the visible insulating material
comprises a thin band running lengthwise of the metal strip at
the distal end of the bead of the outer leg of the U-shaped
cross section of the channel which applies the self-retention
force against the outside of the door edge. The present invention
in certain respects represents an improvement upon an edge guard
of this type in which a ?ortion of the liner is exposed to view.
~rom the standpoint of economy and manufacturing, plastic films
of polyvinylchloride are deemed particularly advantageous. The
polyvinylchloride film can be readily bonded to the metal which
forms the edge guard channeI section and it provides suitable
insulating characteristics. One problem which has been noted
by applicant in connection with polyvinylchloride film is that
lighter colored versions of such film are susceptible to color
change due to environmental factors. This means that the color
range which is commercially acceptable must comprise darker
colors such as black, dark brown, or navy. This limited color
range may not be accepted for all styling requirements for auto-
motive vehicles with which the edge guards are to be used. Lighter
colored polyvinylchIoride films tend to discolor with age, being
attacked by ozone, moisture, ultra-violet radiation, salt air,
exposure to extreme heat and cold, detergents, oil, etc.
The present invention is directed to a new and improved
insulated edge guard which possesses the advantages of poly-
vinylchloride film, yet which also provides for color appearances
which are not limited to the darker shades referred to above
and which are highly resistant to discoloration due to the
factors mentioned above. With the invention, a versatility is
imparted to commercially acceptable performance requirements
for an insulated edge guard. The color appearance of
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the insulation may be chosen to match the color o-f the bright
metal of the edge guard. Alternatively the color may be chosen
to match that of the painted body panel on an edge portion of
which the edge guard is disposed. Still another possibility is
that the color may be different from both the painted body panel
and the exterior of the metal channel. With the first two pos-
sibilities the appearance of the insulated edge guard channel is
rendered virtually like that of uninsulated edge guards in which
the appearance is that of a bright metal strip running along the
edge on which it is disposed.
The preferred embodiment of the invention comprises
for the insulating liner superimposed layers of film. The inner
film is a polyvinylchloride film which is readily a &ered to the
metal of the edge guard channel by procedures described in other
of applicant's patents and patent applications. The other is an
outer film of polyvinylflouride which is bonded to the polyvinyl-
chIoride film by conventional procedures. Polyvinylflouride is
itself not directly readily bondable to the metal of the edge
guard channel, yet it does bond to the polyvinylchloride. Un-
like the polyvinylchloride, the lighter colors of polyvinylflou-
ride do not experience the discoloration problem. Hence the in-
vention achieves a significant improvement in an edge guard of
the type described.
The foregoing features, advantages and benefits of
the invention, along with additional ones, will be seen in the
ensuing description and claims which should be considered in
conjunction with the accompanying drawing. The drawing discloses
a preferred embodiment of the invention according to the best
mode contemplated at the present time in carrying out the inven-
tion.
BRIEF DESCRIPTION OF THE DRAWINGS
_, .
Fig. 1 is a fragmentary side elevational view of an
automobile body showing edge guards on the doors in accordance
with principles of the present invention.
Fig. 2 is a sectional view, on an enlarged scale, tak-
en in the direction of arrows 2-2 in Fig. 1.
Fig. 3 is an bnlarged fragmentary view of a portion
of the edge guard of Fig. 2 taken in circle 3.
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DESCRIPTION OF Th REFERRED EMBODIMENT
Fig. 1 illustrates an ornamental and protective edge
guard 10 embodying principles of the invention applied to each
of the doors 12 of an automobile. The shape of each edge guard
corresponds to the shape of the trailing edge of the correspond-
ing door to which it is applied. The illustrated edge guards
are shown to be generally co-extensive in length with the trail-
ing edges of the sheet metal doors; however they may be shorter
depending upon the specific requirements for a given model of
automobile. As can be seen in Fig. 2 the typical door edge to
which a door edge guard is applied includes an inner sheet metal
door panel 14 around the free edge of which is wrapped the peri-
pheral margin of an outer sheet metal door panel 16. For var-
ious reasons involved in the prevailing manufacture of vehicle
doors, the thickness of the door edge is subject to substantial
variation in dimension, and a satisfactory door edge guard must
be capable of accommodating the substantial variations. Typi-
cally the dimension across the throat of the edge guard is di-
mensioned to accommodate a minimum thickness door edge and the
legs of the edge guard may flex outwardly to accommodate edges
of larger thickness.
Fig. 2 shows the edge guard 10 to comprise a metallic
edge guard channel 18 and an insulating liner 20. The insulat-
ing liner 20 is applied in surface-to-surface contact with the
full surface of one side of the metal strip from which the edge
guard channel 18 is formed and then the laminate is roll-formed
to the illustrated cross section. Details of this fabrication
procedure are disclosed in certain of the above mentioned pat-
ents and patent applica~ions of applicant. The resultant con-
struction has insulated metal beads 22, 24 respectively at thedistal ends o the outer and inner legs of the edge guard chan-
nel. The illustrated cross sectional shape may be considered
as comprising a generally semi-circular segment 26 constituting
the base o the U. The legs of the cross section which e~tend
from the base of the U are formed in accordance with the dis- `
closure of U.S. Patent No. 4,379,377. The cross sectional
coniguration of the edge guard yields the advantage of better
dimensional control in roll forming with the result being a
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strong yet resiliently expansible edge guard construction. The
beads 22, 24 are formed by outwardly reversing the extreme dis-
tal margins of the legs approximately 180. In the illustrated
cross section the reversals are slightly more than 180 each
with there being provided small openings respectively in the
respective beads. However, the beads could be fully closed
with the distal edges being bent back flat against the imme-
diately adjacent portions of the legs. Because the insulating
liner lines one entire surface of the metal strip from which
the edge guard is formed, the resultant beaded construction
has the insulating liner exposed on the exterior of the instal-
led edge guard as thin bands running lengthwise of the edge
guard at the distal end of each leg. Thus the reference numer-
al 30 identifies the band for the outer leg, and the reference
numeral 32 the band for ~he inner leg. It should be appreciated
that with the edge guards installed on the vehicle as in Fig. 1
and with the vehicle door closed it is only the band 30 which
is visible.
As explained above, the prior construction for the
insulating liner was a single layer of polyvinylchloride film.
Because of the discoloration problem the color of the polyvinyl-
chloride film had to be dark in order to be commercially suit-
able. However this limited the acceptability of the edge guard
because of certain styling considerations for certain vehicles.
It has now been discovered that a commercially accep-
table product, both from the standpoint of styling considera-
tion and from the standpoint of color stability, can be achieved.
This is done by makingthe liner a composite construction com-
prising two superimposed layers of film. The insulating liner
20 is shown to comprise an inner film 34 and an outer film 36.
The inner film secures the insulating liner to the metal of the
edge guard channel while the outer film provides the color
appearance for the liner. The outer material is polyvinyl-
flouride,` a material which has good color stability for all
colors, even for lighter shades. The problem however with the
application of polyvinylflouride film to a door edge guard is
that the polyvinylflouride film can not be readily directly
bonded to the underlying base material of the edge guard chan-
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nel (i.e. the metal). However it is possible to adhere thetwo films together to form the insulating liner such that the
polyvinylflouride film is on the exterior while the inner film
of polyvinylchloride bonds the liner to the metal of the edge
guard channel. Thus the invention has the advantage of poly-
vinylchloride film in that the insulating liner can ~e readily
bonded to the underlying metal through the use of bonding pro-
cedures such as heat and~or adhesive, yet the polyvinylchloride
is not exposed to view. Rather it is the polyvinylflouride
which is the visible surface of the liner and which possesses
color stability.
One of the advantages of the invention is that ver-
satility is imparted to the styling of the channel in conjunc-
tion with the styling of the vehicle on which the edge guard
channel is installed. For example, by imparting a silver met-
allic color to the polyvinylflouride film the film color can
be matched to the exposed metal of the edge guard channel which
appears with the edge guard installed on the door edge. Thus,
although a thin band 30 of insulating material therefore ap-
pears along the distal edge of the outer leg of the edge guard,its color matches with the edge guard channel and makes it
appear as if there were no liner material at all at the dis-
tal end of the leg. Another possibility is that the amount of
exposed metal of the insulated edge guard can be reduced to
make the edge guard look thinner by imparting to the polyvinyl-
flouride film a color which matches that of the door. The
automobile door is typically primed and painted to present a
desired exterior color. The polyvinylflouride film may be
colored to match the color of the painted door so that to an
observer the distal end of the outer leg of the edge guard
appears to match the door and hence a reduced a unt of bright
metal of the edge guard is available for view thereby giving
the edge guard a thinner appearance. A still further possi-
bility is that the polyvinylflouride film may be colored to
other than that of either the metal of the edge guard ox the
painted door.
Indeed as a further extension of principles of the
invention it would be possible to apply liner to both sides of
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the metal strip before roll forming. The U-shaped channel will
then comprise not only to the interior of the edge guard being
lined but the exterior as well. By making the color match
that of the painted door a metallic edge guard can be madP so
that its entire exterior matches the color of the painted door.
In other words the advantages of a metal self-retaining are
retained while the color of the edge guard is made to match
that of the vehicle. With the illustrated cross section the
longitudinal edges of the metal strip, even though uncovered,
are substantially concealed from view. The end edges are also
uncovered but are generally not prominent. If deemed appro-
priate, the ends could be covered or protected by spraying or
dipping. Because substantially all of the metal is covered, a
lower grade material (i.e. not bright and shiny) can be used
for the metal channel.
The insulating liner itself may be fabricated by any
of various possible procedures. It may be fabricated as a
laminate of two extruded films and the laminate applied to the
metal strip which is to form the edge guard channel. Alter-
natively other fabrication procedures are contemplated, suchas by spraying the material to form the film, rather than ex-
truding the film. Either one or the other or both of the films
could possibly be -sprayed on. Application by dipping is also
possible. The preferred construction also comprise~ the poly-
vinylchloride film as being substantially thicker than thepolyvinylf~ouride film, this being a more economical construc-
tion.
It is also contemplated that principles of the inven-
tion may be extended to other applications. For example, the
insulating liner can be applied to metal, wood, plastic or
other base materials. In these`applications a desired color
appearance with suitable color stability is provided on the
exterior while the interior may be bonded to the base material
by conventional procedures. Thus it is possible to apply the
insulating liner to a surface of a building panel such a styro-
foam, wood, drywall, plastic, etc. For such applications, the
thicknesses of the liner and of its constituent layers may be
made thicker than those which are used in the door edge guard
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application described above. Such building panels can be on
the exterior of a building where they retain color stability
in spite of being exposed ~o sunlight, ozone, moisture, etc.
It is possible for the base material to be an eavestrough,
downspout, or siding for a building. The laminate could also
be used on automobile body panels instead of paint and primer.
While a preferred embodiment of the invention has
been disclosed it will be appreciated that principles of the
invention are applicable to other embodiments.
