Note: Descriptions are shown in the official language in which they were submitted.
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sackground of the Invention
Field of the Invention
.
This invention relates to apparatus for pre~orming
a wall covering for a tub-recess from a single sheet of
plastic laminate material.
Related Application
This is a division of Serial No. 270,174 filed
~anuary 21, 1977, and entitled Wall Covering For a Bathtub
~ecess and Method of Forming Same.
Description of the Prior Art
There are several multi-piece wall covering kits for tub
recesses on the market today. A common kit comprises three flat
panels of a sheet material (e.g. a plastic laminate~ having a
lS decorative face. One panel is installed on the side wall of the
tub-recess. The other two panels are separately installed on the
two end walls of the tub~recess. It is also known to preform
from fiberglass all three walls of the tub-recess integrally with
a fiber~las~ bathtub. However, prior to my invention, I am not
aware of anyone having produced a preformed wall covering for the
side and end walls of the tub-recess from a single sheet of plastic
laminate material.
The art of bending sheet plastic materials into various
shapes is also well known. The following are examples of known
methods and/or apparatus on which United States patents~have been
granted: No. 2,420,119, granted May 6, 19~7, to Robert M. Boehm
and Aaron A. Ladon; No. 2,744,850, granted May 8, 1956, to
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Christian A. Scofield; No. 2,897,547, granted August 4, 1959,
to Robert J. Clapp, Morton E. Latham and John G. Stan~bury;
No. 3,020,596, granted February 13, 1962, to Robert J. Clapp
and John E. Jamison; and No. 3,574,807, granted August 13,
1971 to Edward A. Heavener. These patents should be consulted
for the purpose of properly evaluating my invention and putting
it into proper perspective with respect to the prior art.
I am also aware that the Formica Corporation o~ Cin-
cinatti, Ohio has proposed bending its one-sixteenth inch
Formica brand laminated plastic about a one and one-half inch
diameter tube which is heated to a surface temperature of
three hundred seventy-five degrees fahrenheit by a thermo-
statically controlled internal heater. The company's
instructions include an instruction to overfrom the material
by bending the material through a one hundred degree arc, and
an instruction to wipe the sanded side of the formed area
with water. These steps are outlined by the Formica Corp~ra-
tion in specifications for a post forming procedure.
Summary of the Inventlon
Apparatus for preforming a covering for side and end
walls of a tub-recess from a single sheet of plastic laminate
material in accordance with one aspect of the invention
includes a support structure; a parallel pair of elongated
forming tubes secured to said support structure a distance
apart substantially equal to the width of a tub-recess side
wall, said tubes including outer forming surfaces of a pre-
determined radius; said support structure including a support
bed between said tubes, the upper portion of which is sub-
stantially tangent to the uppermost portions of said forming
tubes, a press assembly movable relatively towards and away
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from ~aid support bed, said press assembly including an inter-
mediate portion cooperable with said support bed and the
uppermost portions of the forming tubes to hold therebetween
an intermediate portion of a sheet of plastic laminate material
to be formed, and pivotally movable wing portions hinge con-
nected to said intermediate portion along hinge lines which
extend parallel to said forming tubes; said hinge lines being
offset laterally from the forming tubes a sufficient distance
to allow the forming wings, and hence the end portions of the
plastic sheet, to be folded downwardly an amount greater than
ninety de~rees from the plane of the support bed. The appara-
tus preferably includes means for heating the sheet of plastic
laminate in the regions thereof that contact the forming tubes.
As will be described more fully hereafter I locate a
one-sixteenth inch sheet of a standard brand of plastic laminate
material between the support bed and the press assembly of the
forming apparatus. The bed includes a pair of parallel form-
ing tubes having exterior forming surfaces. This apparatus
includes means for heating the plastic laminate material in
the regions where bending is to take place. Preferably such
means is in the form of thermostatically controlled heating
elements within the forming tubes, adapted for controlling
the temperature of the forming surfaces. The press assembly
includes a pair of wing members which are movable to bend the
end portions of the plastic laminate material about the two
forming tubes. Following forming I temper the former corner
portions by applying water to them.
My preformed wall covering comprises a side wall and
two ends walls bent forwardly therefrom. The end portions of
the preformed product normally make an angle with respect to
the side portion which is greater than ninety degrees. As a
result, the end portions must be bent inwardly towards each
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other during installation of the wall covering. This bend-
ing stores energy in the corner portions of the wall product
which serves to bias the end walls of the wall covering towards
the end walls of the tub-recess.
I then loosely fold one end wall of the wall covering
partiall~ over the opposite end wall. Then, I slide the
partially folded wall covering endwise into a rectangular card-
board box having a normal thickness which is substantially less
than the partially folded depth of the wall covering. Movement
of the partially folded wall covering into the cardboard box
causes the side walls of the box to bow outwardly. I then move
the product containing box relatively through a rectangular
opening provided in a rigid forming mandril. As the box moves
relatively through the mandril its side wall, and the side and
partially overlapping end walls of the wall covering therein,
are pushed inwardly. The end walls of the wall covering slid~
over each other and the wall covering assumes a new configura-
tion in which the side wall and partially overlapping end walls
bow inwardly towards each other and the wall covering is with-
in the normal rectangular dimensions of the cardboard box~Then, the end of the box is closed and sealed. Frictional
contact between the wall covering and internal wall portions
of the cardboard box maintain the wall covering in its new
configuration, and the box rectangular in form. The cardboard
box is used for transporting the product between the place of
manufacture and the customer's premises whereat it is installed
within a bathtub recess.
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These and other features, objects and advantages cf the
present invention will be apparent from the detailed description
of the preferred embodiment.
Brief Description of the Drawin~
FIG. 1 is a pictorial view, taken from above and looking
towards the top, the front and the outside of one end of a one-
piece preformed plastic laminate covering for a tub-recess wall
constructed in accordance with the present invention, such view
showing the end walls of said tub-recess covering in their formed
posit.ions in which they extend outwardly from the side wall of the
tub-recess covering an amount greater than ninety degrees, and
said view also showing the molding pieces which are installed on
the upper and front edge portions of the tub-recess wall covering
spaced in position relative to the edge on which they axe installed;
FIG. 2 is a fragmentary portion of one corner and end
wall portion of the tub-recess wall covering with the edge molding
attached, with the portion of the end wall being broken away
between the corner and its front edge;
FIG. 3 is a somewhat diagrammatic view, partially in
elevation and partially in section, of the forming apparatus of
the present invention, said view showing a sheet of plastic
laminate to be formed located between a relatively fixed support
bed and a relatively movable press assembly, with said press
assembly being shown in spaced relationship from the support bed,
and said view showing forming pressure applying wing portions o~
the press assembly in a retracted position;
FIG. 4 is a view similar to FIG. 3, but showing the press
assembly moved downwardly against the intermediate portion of the
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sheet of plastic laminate material, and showing the forming
pressure applying wing portions of the press assembly, and the
end portions of the plastic laminate material in contact there-
with, swung downwardly into a position at the end o their
orming paths, and said view showing excess tempering water
being collected by troughs provided for that purpose;
FIG. 5 is an end view of a tub-recess wall covering
formed in accordance with the present invention, with one end
wall thereof slightly overlapping the other, said view showing
the outwardly bowed configuration which the tub-recess wall
covering assumes when the two end walls are positioned in this
manner;
FIG. 6 is a pictorial view taken from above and towards
one major side, one minor side and one end of a cardboard box
for said tub-recess wall covering, said view showing the semi-
olded tub-recess wall covering being moved relatively into the
box, and showing the opposite end of the box situated in a Eorming
mandril;
FIG. 7 is a view like FIG. 6, but showing the forming
mandril moved into a position near the open end of the box, and
showing the change in form of both the box and the tub-recess wall
covering therein caused by such movement of the mandril; and
FIG. 8 is a view taken substantially along line 8-8 of
FIG. 7, showing the stored configuration of the tub-recess wall
covering within the box after use of the mandril~
Description o the Preferred Embodiment
My tub-recess wall covering kit comprises a one-piece
wall covering 10 which in preferred from is formed from a single
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sheet of general purpose grade (about 1/16 inch thick) plastic
laminate material, such as Formica (trademark) or Wilson-Art
(trademark). The kit may further include a plurality of pieces
of edge molding. Specifically, the kit may include two prebent
inside corner sections 12, 14; one straight upper rear edge
section 16; two straight upper side edge sections 18, 20; and two
straight forward edge sections 22, 24. Sections 18 and 22 are
level cut at corner 28. The opposite ends of such section 18, 20, 22,
24, both ends of section 16, and the two ends of each of sections
12, 14 are straight cut.
The forming of the wall covering 10 will now be described.
A sheet of plastic laminate, preferably general purpose
grade 1/16 inch thick, having a decorative layer on one side and
a backing layer on its opposite side is placed between a support
bed 30 and a press assembly 32. The plastic laminate material 10
may measure approximately five feet two inches in width and appro-
ximately ten feetin length. The material 10 is placed decorative
layer down onto the support bed 30, as shown by FIG. 3. Support
bed 30 carries a pair o~ elongated heating pipes 34, each of which
includes a thermostatically controlled internal heating element.
Tubes 34 include an outer forming surface of a predetermined
radius, e.g. three-quarters of an inch radius. The tubes 34 are
parallel to each other and are spaced apart a distance equal to
the desired width of the side wall portion 36 of the wall covering
10. Plastic laminate 10 is centered with respect to the forming
tubes 34, so that end wall portions 38, 40 thereof will be sub-
stantially egual in width.
Following proper location of plastic laminate 10 on the
support bed 30, the press assembly 32 is lowered down onto the
side wall portion of material 10. The forming tubes 34 are heated
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to the forming temperature o~ the plastic laminate ma-terial lO.
By way of example, for ~orming 1/16 inch standard grade Formica
brand laminate plastic or the like I preheat the internal heating
elements to about three hundred seventy-~ive degrees Fahrenheit.
Then, I increase the temperature by resetting the thermostat to
about four hundred degrees and perform the forming steps as the
temperature is rising. By following this procedure I am able to
orm a standard grade laminate without scorching it.
Press assembly 32 includes a pair o~ wing portions 44,
46 which are hinge connected to an intermediate portion 48 along
hinge lines which extend parallel to the forming tubes 34. In op-
eration, the wing portions 44, 46 are moved downwardly, either one
at a time or together, for bending the end wall portions 38, 40 of
the material 10 about the heated forming tubes 34. The bending
occurs at a relatively slow but steady rate. Pressure is applied
evenly by the wing members 44, 46 until the end wall portions 38,
40 have been moved through an arc greater than ninety degrees, e.g.
one hundred degrees.
Heating of the foxming tubes 34 is discontinued and water
is applied to the backing layer side of the material 10 at the
corners, in order to temper the material. The equipment shown by
FIGS. 3 and 4 is equipped with a pair of spray bars 50, each having
a plurality of outlet openings 52 spaced along its length, and each
being positioned to discharge water onto the formed corners of the
2~ material 10. This type of arrangement is preferred because it
results in a substantially simultaneous distribution of water to
all regions of the corners, so that all regions of the corners will
be substantially evenly tempered. Suitable trough structure 54,
shown in section in FIG. 4, may be provided below support bed 30
to extend the full length of each spray bar 50 and function to
collect any excess water which may be present.
Both the support bed 30 and the intermediate portion 48
of the press assembly 32 may be adjustable forthe purpose of
varying the spacing of the forming tubes 34 and the hinge lines
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for the wing portions 44, 46. By way of typical and therefore
nonlimitative example, this adjustment may be easily done by
constructing each means 30, 48 to include two side portions and
a common base to which the side portions are connected by means
of a plurality of fasteners which provide ~or adjustment of the
positions of the side members relative to the common base. For
example, the Easteners may comprise bolts carried by the side
members which extend through slots formed in the common base
which are elongated in the direction of desired adjustment, with
wing type clamp nuts or the like being provided on the bolts.
A very important aspect of the invention involves the
steps of packaging the wall covering 10 within a relatively small
dimension cardboard box 52, following the forming operation.
Placement of the preformed wall covering 10 within a box will
15 now be described.
Firstly, the wall covering 10 is partially folded into
the configuration shown by FIG. 5. This is done by lapping one
end wall (e.g. 40) over the other end wall (e.g. 38), to produce
a configuration of said wall covering 10 in which the side wall 36
thereof bows outwardly in one direction and the partially over-
lapped end walls 38, 40 thereof bow outwardly in the opposite
diection (see FIG. 5). Care is taken to not overstress the corner
regions of the partially folded wall covering 10.
Next, this configuration is substantially maintained
while one end of the partially folded wall covering 10 is intro-
duced into an open end of the rectangular box 52. Box 52 is
normally rectangular in form and is normally wider than the width
of the partially folded wall covering 10 and has a normal depth
that is substantially smaller than the depth dimension of the
partially folded wall covering 10. This can be appreciated by
comparing FIGS. 6-8 of the drawing.
Next, the partially folded wall covering the moved endwise
into the box (FIG. 6) so that the outwardly bowing side and end
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walls thereof will in turn bow the side walls of the box outwardly
(also FIG. 6).
Then, the bo~ 52, with the outwardly bowed wall covering
10 therein, is moved relatively through a rectangular forming
opening 54 of a rigid mandril 56. The opening 54 is sized to be
substantially equal to the normal outside dimension of the box 52.
As it moves the mandril 56 forces the two sides of the box 52
inwardly and reshapes both the side walls of the box and the side
end walls of the wall covering 10 therein. As this is done, the
end walls 38, 40 of the wall covering 10 are shited in position an
amount suficient to cause the side and partially overlapped end
walls of the wall covering 10 to bow inwardly until the wall cov-
eriny 10 has assume~ a new configuration which is substantially
within the normal rectangular shape of the box (FIGS. 7 and 8).
Finally, the end of the box is closed and sealed.
It was found that the wall covering 10 retained its new
configuration rather than returning to the outwardly bowed con-
figuration. It is believed that this is because the frictional
contact between the backing layer of the wall covering 10, which
layer is relatively rough, and the inner surfaces of the cardboard
box 52 in contact therewith, serve to hold the wall covering 10
in the new con~iguration.
When the wall covering 10 is inside the box its corner
portions are not overly stressed and are protected by the rigid
rectangular corner shape of the hox.
As mentioned above, while being formed the end wall
portions 38, 40 lf the wall covering 10 are bent inwardly past a
perpendicular position (FIG. 4). However, after the formed product
10 has cooled, incluaing after it is removed from the box to be
installed, the two end walls 38 40 make an angle with respect to
the side wall 36 which is greater than ninety degrees~ This is
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shown by FIG. 1 in which the true position of the end walls 38, 40
is shown by full llne and an exactly perpendicular position is
shown by phantom line. Owing to this feature, when the wall
covering 10 is set into place the two end walls 38, 40 must be
swung inwardly towards the perpendicular position. This stresses
the corner portions somewhat, storing energy in the material which
~ends to bias the end walls 38, 40 into contact with the end walls
of the tub recess.
Also, it has been found that the wall covering 10 will
easily adapt to a tub~recess that is not exactly regular, viz.
the walls are not plumb and/or square with each other. If general
grade material (1/16 inch thick) is used, the wall covering 10 may
be installed without it being necessary for all portions of it to
be flat against a wall portion of the tub-recess. The material is
stiff enough to provide a solid installation even with some place
existing behind say one or both of the corner portions of the tub-
recess.
During installation it may be necessary to trim one or
more of the edges of the wall covering 10, particularly if the
tub-recess is not true. This can easily be done. If some cutting
ofthe metal trim is necessary, it will involve only cutting off
a portion of a squared end of one or more of the straight sections.
According to an aspect of the invention, I form the
corner sections of trim 12, 14 by inserting a piece of the plastic
laminate materia]in the slot provided therefore and the bending
both such material and the trim piece together. Except for the
selection and cut of the pieces, the edge materialis the standard
edge material which has been used for years in connection with
plastic laminate material. It includes a relatively deep back
flange portion which is hidden behind the plastic laminate material,
a web which extends across an edge of the material, and a front
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flange which extends over a small edge portion of the front face
of the plastic laminate material.
The invention may be embodied in other specific forms
without departing from the spirit or central characteristics
thereof. The present embodiment is therefore to be considered
in all respects as illustrative and not restrictive, the scope oE
the invention being indicated by the appended claims rather than
by the foregoing description, and all changes which come within
the meaning and range of equivalency of the claims are therefore
to be embraced therein.
