Note: Descriptions are shown in the official language in which they were submitted.
The field of the inventlon yenerally comprises
automotive structural members know~ as "load floors", a
ter~ general]y applied to a core or bracing plate that is
inserted into or connected with the back of a vehicle bench
seat and inkended to be folded d~m ~or carryiny loads.
This core or bracing plate must furnish sufficient strenyth
to the seat back that the latter is sae in the event o
shocks and accidents and will not yield, bend or collapse~
The core must provide the connections to enable the seat
back to be mounted in erect or angled position while the
seat is being used by passengers. ~dditionally, the core
must provide hlnge means needed to enable ~he folding of
the seat back between the two positions in which it is
inkended to be used. Still further, the core must provide
lS anchoring means ~or the various brackets xequired to
connect the seat back in its ~loor position, either alone Or
with other members. The core or bracing plate must be strong,
suicient enough to sUpport any kind o~ load which can be
accommodated in the vehicle without yieldi~g or co~lapsing.
~ Other re~uirements o~ such an article include
durability, lightness in weight and capability to be produced
economically to enable a vehicle builder to incorporat~ the
load floor into a vehicle o~ low selling price.
Prior available load floors have been construcked
o~ steel and/or, more recently, o~ aluMinum (as an attempk to
liyhten the load ~loor).
_ 1 -
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Kno~n load ~loors of the type concerned herein
have been fabricated of many parts and pieces, usin~ welding
and fastening techniques. ~ibs are provided for strength,
either pressed into the metal plate or welded onto the same.
Attachment of hinyes, conne~ctors, brackets and the like
complicate and increase the cost of rnanufacture. Metal
load floors require special tools, dies and fixtures for
fabrication which increase the capital expenditure requiredO
Dif~erences, say in models of vehicles, call for such
design differences as to greatly increase the required
expenditure.
Notwithstanding the modern production methods
available, load floors are heavv, expensive, and have a
tendency to distort through use. When subjected to great
weight over a period of time in use as a floor or as a
seat back, metal cores will bend and retain the distortion.
~ Structural members for vehicles are known to be
formed from mo~ded synthetic resins. Such members have
~ been formed Or fiberglass reenforced epoxy resins, either
molded in forms and cured therein, or applied in multiple
1 amLnas~l In the event such members are intended for uses
wherein they are subject to stress, they must be ~abricated
in situ by k~own techni~lles or constructed in much the same
manner as metal members, usually manuall~. Conve~tiona
~ production methods call Eor the con~truction of large mold~
:
lnt;o which the layers of fiberglass and the resin are
alternately laid after which the article is curcd.
L~95~6
NOtwithstanding such techniques, it is belie~ed that
- there are no members o~ fiherglass-reenforced epoxy
resins, or even of the resins themselves which ar~
completely enclosed and ho.~low. Thi.S type of molding
is even more expensive than metal fabricatiorl and not as
strong and durable.
In addition to ~ e as the core of a fol~
down vehicle seat, the load floor may be emplo~ed
in vehicle doors which must support glass panes and
mechanisms ~or raising a~d loweriny the same and side
paneIs which serve as doors or vents without glass
and which must be operated. Any parts which are
required to be strong and durable and which carry
equipmant and accessories advantageously may employ
lS the load floor and techniq~es of ma~ufacturlng same
as described herein.
Accordingly, there is provided a load
flo~r~such as for example, for use as the core of a
fold down multi-purpose vehicle seat back or the ; -
llke which is ~ormed by blow-molding~ The load floor
i5 a completely enc}osed hollow article o~ inteyral
~-~ construction which has a large planar area and a
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5 ~ ~
relatively small dimension in thickness. Means are
provided for the securement of hinges and the like
to the load floor.
Accordingly, the load ~loor ls formed with
parallel walls connected around their edges by an
integral peripheral wall. Tying links connect between
the parallel walls, being distributed throughout the
area of the load floor generally, these links being formed
by indented parts in one parallel wall extending to
the inner sur~ace o~ the other parallel wall and
engaged and w~lded thereto during the blow-molding
process, or formed on both parallel walls and meeting
in a welded and engaged connection between the
paralLel walls.
Socket inserts for fastener connection are
provided which are integrally molded in place during
the blow-molding process. There are tying links in
the vicinity of these i~serts to provide added
strength at the resulting stress areas.
' The load ~l~or has incorporated therein a
channel shaped steel bar, the same beiny introduced
into the mold at the time that khe cor~ is being blow-
molde-, the bar being locked in pl~c- dur~ny this
.
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5'~6
process. q~he b~r is arranged in the direction of the
maximum shrinkage of the core and is disposed in
a groove so that it can slide slightly duriny
curing of the resin and will not result in the
core being bowed as it comes out o~ the mold.
Figure 1 is a relatively simple
diagrammatic view shGwing the layout o~ seats in a
station wagon vehicle in order to illustrate the
location of a seat back core intended to serve as
a load floor additionally.
Figure 2 is a front elevational view o
a fragment o~ a seat back core constructed in
accordance with the invention.
Figure 3 is a rear elevational view of
the same.
~ Figure 4 is a fraymentary sectional view
taken generally along the line 4-4 of Figure 2 and
in the indicated direction on a much larger scale.
~ Figure 5 is a vert1cal sectional view taken
general~ly along the line 5-5 o Figure 2 and in the
~indicated direckion on a somewhat laryer sc~le.
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3~
Figure 6 is a Eragmentary sectional view
taken generally along the line 6-6 of Figure 3 and
in the indicated direction.
Figure 7 is a fragmentary se~tional view
taken generally through a modified form of the
invention to show a tying link o~ a type different
from that shown in Figure 6.
Figure 8 is a fragmentary elevational view
oE a modified form of the invention to show a
variation in the kind of indentation used.
Figure 9 is a fragmentary top plan view
of a modified embodiment of the load floor constructed
in accordance with the invention.
Figure 10 is a sectional view through the
load floor of Figure 1 along the line 10-10 and in
the indicated direction.
Figure 11 is an enlarged fragmentary
sectional view taken generally in the same manner as
Figure 10 but showing a modified form of the invention.
Figur0 12 is similar to Figure 11 but of
still another modi~ied form of the invention.
.
~ 6 --
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Figure 13 is a diagrammatic top plan view
of a load f]oor of modifiecl form and sho~Jing the
manner of mounting ~wo steel reenforcement members
in the core.
Figure 14 is a diagrammatic top plan view
similar to that of Figure 13 but showing another
arranyement for mounting the steel reenforcement
members.
Figure 15 is a fragmentary sectional view
through one part o~ a mold for blow-molding a load
floor showing the construction of molding surface of
the part for carrying a reenforcing member and showing
the member in exploded disposition as it is being
installed into the mold part; and
Figure 16 is a fragmentary perspective view
of the mold projection at one end thereof showing the
construction to enable the reenforcing member to slide
during the curing of the load floor.
The load floor contemplated herein is
intended to deflect under pressure which gives it
great strength, the flexure being effected by resilience
and being followed by recovery. In contrast, metal
members assume a permanert set if deflected.
.
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~ . . . .
Deflection incre~ses with the length of
the load floor~ In the load floors which are intended
for vehicles larger than so-called compact cars, this
de-flection may be undesirable. Even in smaller vehicles
it may be desired to limit the deflection or prevent
it entirely.
~s stated previously, the invention herein
is considered with the load floor particularly for
automotive vehicles formed by blow-molding techniques and
having unusual strength and other advantages.
The skrenyth is achieved by the use of tying
links which are automatically formed in ~he member during
its molding process and by distributing khese links
yenerally about the member. This use of such tying
links combined with the box sections resulting which are
achieved by the blow-molding technique produce the
unusual advantages~ The product is rigid enough to
support all of the weight that can be supported by metal
load floors and more; it flexes and absorbs shock without
setting; it cannot rattle or lose its integrity as in the
case o~metal load floors because there i5 nothing to get
loose, the me~b r being an integral article; it cannot
injure passengers because it can be made without sharp
edges; it can be exposed because it can be molded with
a surface texture and finish nok requiring further
processing; lt is light in weiyht; it i5 economical.
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Blow-moldlng as referred to herein is a technique
whic~ has been developecl in relativeLy recent tlmes wherein
a charge of plastic such as a polymer which is readily
converted into a plastic taffy-like consistency, is extruded
Prom a so-called head in a tubular form depending vertically
from the head. This ~orm is called a parison and the
extruded amount oP plastic is ad~usted to equal that used
in the finished article with allowance for flash and similar
slight waste. The bottom end of the parison is open but
may be closed by pinching before molding if needed because
oP the shape to result to enable some in~lation before
the dies close.
After the parison has bee~ discharged completely,
but while still d~pending from the head the opposite sec~tions
of a vertically split two-part mold are tightly brought
together with the parison captured ~etween them. The mold
completely encloses the parison but for a passageway for air~
This passageway may be provided by a nozzle depending from
the head~ it may be provided in a nozzle that is mounted
to be surrounded by the closing mold at the bottom oP the
blow-molding machine, it may be provided by a side nozzle
carried by the mold or it may be a small opening in the
mold through which a Pine needle or the like has been
inserted a~ter the mold par~s are brought together. Air
may be admitted while the parison is formed or slightly
a~ter its Pormakion and beEore the rnold parts are brought
together in order to shape the parison more geometrically
to meet the yeneral shape into which it T~ill eventually be
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formed precisely. This woul~ be the case where the final
shape is a radical change frorrl the cylindrical form
of the parison and requires the bottom en~ of the parison
to be pinched together to enable pre-expansion.
After the mold closes, admission of air into the
tubular length expands the plastic resin into the mold,
the extruding process having been dlscontinued when the
mold closed~ After the plastic has set, the mold is opened,
the air pxessure being discontinued at any convenient
time, and the finished product is removed. There is
usually flash of a small amount around the parting line
of the mold and this is readily trimmed off, either by
means of a band saw or manually, depending upon the
nature of the article. The plastic is still hot enough
to enable this to be done easily and quickly.
Thereafter the process is repeated.
Obviously there is no need for layering any
materials in the mold, no curing, no handling o~
dangerous and volatile materials, no fabricating and
no requirement for metal working tools and dies~ One
mold does everything.
Referring now to the drawings, in Figure 1
there is illustrated a layout in the compaxtment 9 of
a so-called station wagon 10 which is relatively large
25~ in this instance, but could have two seats instead of the
three shown. The ~ront or driver's seat 12 has a seat
back 14 which is usually hinged for some movemenk but
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J~5~c~i
not intended to be ]aid flat. It could ha-~e a COre but
this is not necessary. The passenger seats 14 and 16 are
provided with seat backs 18 and 20 respectively which are
intended to be laid flat when it is desired to use the
station wagon lO ~or carrying goods. Various constructions
provide for one or both of the seat backs 18 and 20 to be
laid ~lat and include various types of connectors, brackets,
hinges and the like connected to the bottom of the
compartment 9, the side walls, etc. Mone ~ these is
shown since there are so many variations. The mechanisms
may provide for sliding o~ the seats 14 and/or 16 to
achieve the desired load-carrying capacity and compartment
configuration.
The rear faces of the seat backs 18 and 20 will
normally be uppermost in the compartment 9 whe~ the seats
are arranged to be laid ~lat and it is required that the
interior of the seat backs be provlded with a rugged core
that can serve as a floor. The cores are sh~.~ at 22 in
phantom lines in Figure 1, these being concealed within
the seat back and covered with some klnd oE material 5uc'n
as carpeting or rnetal or could be exposed in which case
they woulcl be finished in a color and texture to match
the decor of the vehicle.
The inventi.on is concerned with the construction
of these cores 22 as an example which shall be re~erred
to hereinafter as load floors 22. For example, the doors 24
and 26 might advantageously be made OL- load ~loors formed
in acc~rdance with the invention.
11 -
Looking now at Figure 2 there is illustrated the
left half of a load floor 22 constructed in acco~dance with
the invention, the right half being identical. The view
is called an elevational view in the drawings ~ecause while
the thickness of the load floor 22 is about an inch (2 l/2
centimeters) for the example to be detailed, the vertica3
dimension is about 21 inches (54 centimeters) and the
horizontal dimension is about 49 inches (1 1/4 meters) the
normal orientation of the load floor 22 is generally
vertical baing usually canted. when in use as a floor it will
be laid flat and the surface seen in Figure 2 will be the
bottom while the surface seen in Figure 3 will ~e the
uppex one.
The load floor 22 is formed of a fully enclosed
(but for a small blow hole) holl~w plastic article which is
integrally formed ~y blow-moldiny techni~ues. There is a
front wall 28 which will normally be hidden by the upholstery
of a seat cushion of the seat back such as 18 or 20, a
parallel rear wall 30 which wilL have the load engaged
thereon. The front surface is designated 32 and the rear
surface is designated 34. In the particular model shown
there are winys 36 at th~ upper corners of the load floor 22.
A peripheral wall 31 connects the parallel wall~ 28 and 30
completely arou~d their edges.
The load ~loor 22 has a series of indentatlons 38
which are formed in the front wall 28 and hence are
discontinuances in the plane of the front surface 32. As
~een in Figure 2 these indentations 38 are relatively
evenly spaced frusto-pyramidal indentations that are
distributed over the entire surface 32. There are twent~
complete indentations 38 on the left side, an irregular
shaped indentation 38-1 at the curve 40 be].ow the wing 36,
two complete indentations 38-3 in the center and thexe
will also be a repeat of the twenty complete indentations
and the irregular shaped 38-1 on the right side.
The indentations 38 axe formed by providing
suitable protrusions of frusto-pyramidal shape in one of
the mold parts which close around the extruded parison
tube described above. The dimensions of the protrusions
are chosen so that the height is sufficient to bring the
bottom end 40 (Figure 4) thereof into engagement with the
inner sur:~ace 42 of the wall 30 while the resin is hot
and plastic. As a result there .is a welding of the said
bottom 40 to the wall 30 and a thickened connection is
formed.
When cooling kakes place, the resulting formation
44 comprises a rigid tying link or beam extending between
the parallel walls 28 and 30. This means that there will
- be forty-two such tying ~.inks of frusto--pyramidal
configuration and two irregular shaped links formed by
the indentations 38-1 between the parallel walls 28 and 30
This resuLts in a light weight~ hollo~7, extremely strong
structure that can caxry considerable weight. Furthermore,
the structure wil.l flex to some extent which means that it
-- 13 ~
can readily resist shocks; nevertheless the flexure will
not result in any permanent set being effected in the load
floor 22.
Samples of load floors constructed as described
and of the dimensions indicated have passed all safety
standards tests and weight tests of the automobile
manu~acturers to which the same have been subjecked with
results as favorable as and in some instances more
favorable than those of metal load floors of the same
general dimensions intended for the same models of
vehicles.
~ The thickness of the sections 40 are about 5
millimeters comprising an approximately doubling of the
normal wall thickness. This is achieved in a blow-molding
process wbere the normal technique calls for the wall
thicknesses to be substantially uniform all over the
article being formed.
The securement of hinges, brackets, connectors
and the like is a relatively simple matter with the load
fl~oor construction of the invention. The plates to be
secured can be set into depressed or decreased thickness
areas by the ready expedient of building the depression into
the mold. This is done without sacrificing the strength of
the member.
Thus, a ~astenirlg member in the form of a plate,
comprisiny half of a hinge or the li.ke, may be expected
.7~S~;
to be ~ecured on opposite lateral ends of the l~ad floor
22. ~ securing area is formed at 46 which is spaced below
and parallel to the surfa~e 32, beiny joined to -the surface
by the angled joint 48 surrounding the securing area 46
and blending by relatively smooth curves, if desired.
The joint 48 ls nothing more than a continuation of the
wall 28 and of the same thickness as is the upper wall 50
of the securing area 46.
The plate or other mer~er to be attached can be
suitabl~ perforated for screws of threaded bolts (none of
which is shown) and these screwed into nuts 52 that are
molded in place as inserts in the wall 50. ~he mold
forming the load floor 22 will have suitable structures
for orminy the anchors 54 for the nut inserts 520 A
simple technique of effecting this can comprise providing
pins in th.e mold with the nuts engaged on the pins. After
the mold is opened, the load floor 22 is pulled off the
pins with the nuts permanently secured.
The portion of the load floor 22 where the
plates or hinges are to be fastened at the areas 46 can
be located such that it is impractical to provide the
strengthening efect o.~ the depressions which are
designated 38. It will be noted that the reason or the
depressions 38 being pyramidal is that the cross-section
of the tying li.nks 44 formed thereby in a plane parallel
to the wall.s 28 and 30 at the thickened bottom end 40
i.s square. This provides the maximum area of connection
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for any given geometric configur~tion whose m~imum
dimension is one side of the square. The result is a strong
box section beam.
In the case of the area 46 in the immediate
vicinity o~ the three nut inserts 52 shown, the frusto-conical
depression 54 in the wall produces a tying link 56 and a
thickened bottom 58 which substantially strengthens the
load floor 22 at this critical location~ The configuration
o-f the tying link 56 is such that it can be brought very
close to all three of the circularly disposed inserts 52.
The dimensions of a practical device can be proportionally
determined ~rorn those given a~ove and applied to Figure 4
to note that the diameter of the upper entrance 60 of the
depression or indentation 54 is slightly more than 4
centimeters.
In Figure 2, there are two plaques seen at 62
and 64 these being the thickened rectangular plates
integr~lly formed during the blow-molding process normally
to strengthen the load 100r 22 at ~ocations where latches
- 20 or brackets are to ~e secured on the opposite face of the
member 22. Thus, the plaque 62 is congruent with the ~ottom
of the rectangular depression 64 and actually comprises the
bottom floor o~ that depression~ A bracket or latch plate Or
other hardware is intended to ~it in the depression 64,
~1ell below the suxface 34~ The depression ~orms ~ide walls
66 and 68 which are tape,red and connect with the wall 30
as best seén in Figure 5.
_ ~,~, _
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l~he same arrangement is provided at the bottom
of the load ~loor 22 where the plaque 64 i~ located. It
comprises the thickened bottom wall produced by the
depression 70 that is formed in the front wall 30. Note
that the particular design provides for the bottom of the
entire load floor 22 to be tapered as at 72 which is no
problem at all in the blow-molding process since it merely
means a modification o~ the mold from ~hat it would be if
the bottom edge were relatively squared off as the top
edge 74.
In the case of the depression 64, the hardware
article that is to be accommodated is intended to be
secured to the load floor 22 by means of screws or bolts
that are to be threaded into the nut inserts 76 and 78
that are molded into anchor formations such as 80 (Figure 6)
which are cimilar to the formations 54. The inserts 76 and
78 are disposed on opposite sides of the depression 64
alongside o~ the side walls thereof, somewhat spaced from
the nearest frusto-pyramidal formation 38-5 and its tying
link. While it is true that the side wall~s such as 66,68
and thos~e not seen in section in the views but provided at
82 and 84 (seen in elevation) are connected between the
parallel walls 2S3 and 30 in the same manner as the tying
links ,such as 44. For additlonal strength, smaller tying
link~ ~nay be provided imm~diately adjacent to the inserts 76
and 78~ ~hus, relatively small diameter cylindrical
indentations 86 are provided as sh~m in Figures 3 and 6
_ 17 --
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producing small tying links 88 haviny thickened floors 90
where they are welded to the wall 28 during the blow-molding
process. ~he depressions 86 are sh~n as slightly
frusto-conical since preferably they are tapered to provide
the necessary draft for easy mold separation.
Th~re are no inserts illustrated adjacent the
depression 70 since it can be presumed that this formation
is to clear some hardware that is othe~ise secured
~ external o~ the load floor 22. Certain forms of the
invention could have the required inserts and strengthening
tying links.
The invention can be embodied in load floors of a
great variety of configurations and having many different
types of hardware secured. Likewise tail gates, doors,
panels carrying accessories and equipment and the li}ce can
be constructed in accordance with the invention. The
blow~molding process applied in the manner disc1osed provides
unexpected strangth to such members.
It is clear also that the tying links need not be
ZO formed fully in one of the walls and nok in the other. In the
case of'a load floor such as described it is convenient to
have as few indentations and impressions as feasi~le in that
surface which faces up for obvious reasons. In a member where
there is not of great consequence, or even in areas of a load
25 ~ floor where it is not important, the tying links can be
formed partially in each of the walls of the hollow mernber
duriny the blow-rnolding process.
In Figure 7 there is shown in section a fragment
of a structural member 90 which has a front wall 92 and a
rear wall 94 each of which is provided with an indentation
such as 96 and 98, respectively, of substantially the same
geometric configuration and alignment. Each indentation 96
and 98 extends hal~way into khe memher 90 and the dimensions
are chosen so that during the blow-molding process the bottom
touch and weld together to form the double thickened web 100.
The re~ulting tying link 102 is of different formation than
a li~k such as 44 or 88 or 56 but serves the identical
function ~ to provide a beam or transverse struc-tural rnember
strengthening the resulting article. The sectional
configuration could be square, circular, etc.
In Fiyure 8 there is illustrated a plan view of a
fragmerlt of a structural member 104 in whi~h the depression
106 is rectangular instead of square in section thus
demonstrating a modified form of the invention. The
- depression could be of any geometric configuration which is
convenient or economical to make so long as there is a
touching of the bottom such as 108 with the interior surfàce
o~ the opposite wall to weld together.
A typical blow-hole as re~uired in blow-molding i~
~h~7n at ]lO in ~igure 3.
q~he specific resins preferred in blow-moldin~
~5 structllral rnembers intended to take rathex heavy punishment
are hiyh density polyethylene and poLypropylene but these
are not to be considered as limiting the scope o~ the invention.
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Referring to F:LgUreS 9 throuyh 16 inc~lusive, a
rnodified embodiment of the inventio~ is illustrated, the
same differi.ny Erom load floor 22 primarily in having a
reenforcing steel structure molded into the load floor
permanently during the mo.~ding process.
In Figure 1 and its sectional view in Figure 2
are shown load floor lO' and has a front wall 112 provided
with indentations of several types and a planar rear wall
114. The ront and rear walls a~e connected by a peripharal
wall 113 all around.
The rear surface 116 is plain in this example.
The indentations include frusto-pyramidal indentations at
118 along the upper edge, transverse elongate rectangular
indentations at 120, and an elongate recta~gular lndentation
122 which extends throughouk the majori~y of the length of
the load floor lO'. All indentations are tapered towards
their bottoms and each results in a doubled thickness of
the plastic walls 112 and 114 where they come together and
are welded in place during the molding process as heretofore
described.
I These indentations all provide the connecting
links which tie the walls 112 and 114 together, a typical
tying link being indicated at 124 and being formed by the
surrounding waLls of the indentation li8. The tying links
of different shaped indentations will generall.~ lollow the
shape of the i.ndentation. Thus, the tying links of the
rectangular indentations 120 comprise rectangular
- 20 _
formations 126. There ma~ be smaller indentation~ such as
at 12% providing smaller tying links at locations 130
where hardware is intended to be secured.
rrhe lndentation 122 extends substantially along
the entire length of the load floor 10' and is a steel
reenforcin.g member 132 locked into lts side walls, having
been molded into l~ad floor 10' at the time of its formation.
The member 132 is of channel construction and may be
stamped or bent from cold rolled sheet steel of 14 gauge
steel (.0747" thick)o The channel side arms 133 are bent
outward as best seen in Figure 10 to conform closely to
the tapered configuration of the indentation 122~ The
dimensions are chosen so that the depth of the channel
me~nber 132 is substantially less than the depth of the
indentation 122 so that when molded there will be plastic
material engaging along the free edges o~ the channel ~ :
arms 133. This results in the locking engagement which
prevents removal of the reenforcing member 132.
In a practi~al example, the depth of the
indentation 122 measured along the angled side walls was
about seven eighths inch wh.ile the equivalent dimension .
of the side arms 133 of the reenforcirlg member 132 was
about one half inch, re~ulting in a block.ing bead or
fGrmation L34 about thrse eighths of an inch wide along
the entire lqngth of the reenforcing member 132~
. In the blow~moLding of re:Latively larye elongate
members such as the loa~ floor of the invention,
shrinkage occurs to a high degree in the direction in
which parison has been fo~med. ~oyically, the parison
is blown in the long dimension of the load floor. The
shrinkage resulting during the curing of the molded object
can be as much as .018 inch fox each inch of length.
Considering that a typical load floor will extend across
the interior of a vehicle cab and have a length of 50 inches
and more, the shrinkage can amount to nine tenths cif an inch.
Steel expands heat and contracts with cold, but the
contraction during the molding process is insufficient
to match the shrinkage of the resin.
Since it is essential that the steel reenforcing
member be locked into the load floor, the problem o~
preventing the core from bowing seems insurmountable.
According to the invention, the construction of the
reenforcing member and the manner in which it is placed in
the mold during the molding process obviates this problem
by permitting the member to slide relative to the load
floor during curing.
It will be noted that the indentation 122 is
substan~iall,v greater than the lenyth of the member 132 so
that there is a free portion at 136 formed at opposite ends
of the indentation 122. l~his space i5 provided primarily
to enable the sliding movement of the member 132 during the
curiny of the load floor 10' which occurs primariLy aEter
it has been removed from the mold and is cooliny. This
freedom to slide prevents the reenforciny mernber 132 ~rom
- 22 -
v 6
being :~orc~d against any part of the load floor 10 ' which
coul.d result in bowiny of the core or separating th~ walls.
I~ Figures 11 an~ 12 two dif~erent constructions
are sho~n. The core 10" of Figure 3 uses a reenforcing
member 132' which is similar in construction to the member
132 in that it has the outwardly bent channel arms 133'
to conform to the walls o~ the indentation 122' but in
addition, has small lips or flanges 138 along the free edges
of the channel arms. With this form of reenforcing member,
when molded there will be a more positive locking action
because of the formation o~ the pockets 140'by plastic
that tries to follow the contours of the member 13Z'. It
should be realized that in blow-molding the parison is a
tube o~ plastic having a su~stantially uniform wall
throughout and when that wall is blown into a mold it
tries to follow every contour of the mold. As will be :~
explained, during the molding process the reenforcing
member 132' is acting as an integral part o~ the mold
and the parison wall will envelope the same and produce the ~:
locking pockets 140'on opposite edges o~ the member 132'.
I The load floor 10"' of Figure 12 uses a reenforcing
channel member 132" that has substantially ring angle arms
133"each provided with a small lip 138" that is locked
into a pocket 140" during the moldiny of the load floor
10"' in the same manner as khe load floor 10".
Figures 11 and 12 are on a larger scale than
: Figure 10 sO ~hat it is more readi]y seen that the tyin~3
links produced b~ the indentatlons are formed at locations
~3
where the bottom ends of the tying links will wel~ to
the opposite wall and forrn a double thickness thereat.
Thus, the indentation 122' produced an elongate tyiny
link 142' that extends the majority of the lenyth of
the load floor 10" and has the thickened portion 144'
at its base.
In molding the load floor 10', 10" and 10"'
where, for example, all of the indentations are formed
in one wall of the core and the other is substantially
unindented, the mold will be made out of two parts, one
of which is flat-faced and the other of which has
projections. In Figures 15 and 16 there are illustrated
fragments of a mold which has ths projections. In the
views, the projection 150 is intended for one o~ the
indentations 118, for example, and the projection 152 is
intended for the indentation 122 or 122'. These are formed
solid with the body o-f the mold I54 and will be of suitable
configura'cion and dimensions to provide the desired
indentations.
The projection 152 has the same contour and
dimensions at its ends as the projection 150 thereby
providing for the indentation ends to produce the ~ree
space at 136 mentioned above and indicated in Figure 9.
This forms a ~light protuberance 156 at each end of the
Z5 projection 152. The depth of the protuherance 156 is
approximately the same as the thickness of the channel
shaped reenforcing member which is to be mounted to the
projection 152.
- 2~ -
s~
In f~bric~tiny the mold part 154, the projection
152 can be cast or machine~ from the block or can be formed
separately and attached hy machine screws. If removable,
different forms of projections can be used with the same
mo'ld base 154.
The mold base 154 is intended to accomrnodate the
reenforcing member 132 or 132' which is laid onto the
cutaway portion shown on the projection 152 and held in
place as the mold is used. Obviously a new channel shaped
reenforcing member will be used each time that a load floor
is formed since the act of molding locks the reenforcing , ~ , -'
member 132 ox 132' to the load floor. In Figure 15, a
reenforcing member oE the construction shown in Figure 11 is
poised to be mounted on the projection 152~ It is dimensioned
so that it will not reach the upper surface 158 of the base 1540
Its length is such that it will ~it between the end
protuberances 156 so that when the seat core is molded,
there will be nothing to prevent the channel shaped '
reenforcing member 132' from freely sliding endwise. The
protuberance 156 will form the end of the indentation 122 or
122' as d~eep as the normal indentations and hence leave the
sp~ce 136 for movement of the reen~orcing member 132 or 132'.
The maximum shrinking of the lead floor will occur
along it~ length and hence it is best that the reenforcing
member be disposed to be able to slide along this dimen.~ion.
Actually, the utility of t,he reenforciny member is rnaximum
when disposed lenythwise of the load f'loor.
5~
The ~ecurement or mountiny of the reenforcing
member 132, 132' or 132" to the mold part before bringing
the p~rts together is capable of boing achiev~d by different
means. SelE-~adhering tape can be usecl under the members;
vacuum openings can be utilized to hold them in place; and
a simple magnetic arrangement could be used. In Figuxe 15,
permanent magnets 62 can be mounted along the length of the
projection 152 flush with the upper surface to hold the
reen~orcing member 132 or 132' in place furing the molding
process.
The reenforcing rnembers 132, 132' and I32" are
intended to prevent flexure of the load floor and to strengthen
the sa~e. Different arrangements can be used for different
purposes.
In Figure 13 there is illustrated a load floor
which has two reenforcing members 164 and 166 molded therein
to provide great strength and stif~ness.
In Fi~ure 14 there is illustrated a load floor
in which there are two reenforcing members 168 and 170
'arranged end to end but separated in the center. In this
case, the only place where flexure can take place is in the
center~ hence the floor will be permitted to f e~ ~ut only
to a limiked extent.
' It is pointed out t,hat the addition of metal members
to the blow-molded load floor does not add substantially to
the cost thereof because once the mold has been constructed,
it requires only a few seconds to mount the reenforcing member
- 26 -
into the mol~ before brinyiny the parts together in the
molding machine~ This is no-t the same effect as fabricating
the conventional sheet metal load floor because, when
the seat core of the inventiOn is withdrawn from the rnold,
it is completed but ~or the attachment of hard~are. The
reenforcing members can be drilled, tapped or provided with
studs and the like (entering suitable sockets formed to
clear in the mold base) so that hardware can be attached
directly thereto if desired when assembling the same to
the vehicle.
In the specification and claims the walls 28 and
30 have been described as parallel. These walls need not
be geometrically parallel bu'c could be at a slight angle
relative to one another to provide a tapered load floor
or the like. Likewise the walls could have different or
the same curvatures. Reference to "parallel" is ~or
- convenience and not intended as limiting.
Summarizing, the load floor has been described as
formed as a bIow-molded member out of polyethylene or other
20 o ~he synthetic polymers conventionally used in blow-molding
techniques. It emerges from the mold as a completely finished
article but for khe need ko attach the hinges, brackets and
connectors. Inserts may be placed in the mold be~ore each
charge carrying nuts or other socke-ts which are pecmanently
mold~d into 'che ~ini~hcd article and will thus receive
~asteninc3 means when lnstallation occurs.
Fabricated metal load ~oors are rnade as a unit
from multiple pieces and such unit is not very pleasant in
_ 27 -
' ' ''' '', ' ' ~ ' ', ' ' ' ' ' '.' ' '" ~ '' '.' . , ,'.. ' ' '' '' ;' " '
appearance. Such load floor construc-tion normally is buried
in the upholstery of the seat back, those par-ts which of
necessity must protrude being carpetecl, painted or otherwise
finished.
As one would conclude from the preceding, a load
floor constructed in accordance with the invention enables
the surface of the article to be molded with any desired
texture built into the mold, such as, for example, graining.
Further, the plastic used can be of any desired color
without difficulty. ThUs, it is feaslble to construct the
seat back so that the floor load is exposed. This provides
a hard surface for the floor when used to support goods.
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