Note: Descriptions are shown in the official language in which they were submitted.
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DOUBLE SKIN DOOR APPARATUS
Field of the Invention:
The present invention is directed to a hollow core door having a perimeter
frame
and a pair of reverse molded wood composite door skins having an exterior
surface and
an interior surface secured to opposing sides of the frame. At least one of
the skins has
an outer planar area, an inner planar area, and an asymmetric profile
surrounding the
inner planar area, and interconnecting and integral with the outer planar area
and the
inner planar area. The asymmetric profile area has a convex portion extending
outwardly
from and relative to the plane of the outer planar area.
Background of the Invention:
Man-made boards, such as fiberboard, e.g., medium density fiberboard;
hardboard; chipboard; oriented strand board-fiberboard composites; particle
board;
oriented strand board-particle board composites; and the like, may be formed
into articles
having contoured portions simulating stiles, rails, panels, or other desired
features. Such
articles may be formed to include one or more interior depressions or raised
contours
simulating panels or other decorative features. Such formed depressions and
contoured
portions may replicate a natural wood paneled door.
With respect to conventional doors, molded door skins may be adhesively
secured
to a wood frame support structure to produce a finished door. Rails and stiles
may also
be used to provide additional structural support for the door. Such doors are
well known
in the art, and provide consumers with an aesthetically appealing, yet cost
efficient
alternative to traditional, solid wood doors.
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For example, U.S. Patent 5,782,055 to Crittenden discloses an asymmetrically
formed door and a method of making the door. The asymmetry allows the door
portion
inwardly from its perimeter frame to warp in response to temperature and
humidity
conditions without warping the perimeter frame. Accordingly, the door
perimeter frame
remains in its original planar configuration. The disclosed door comprises a
pair of
asymmetrically configured skins secured to a perimeter frame, with a foam
disposed
between the skins. Generally, the door is used as an exterior door. U.S.
Patent 5,074,087
to Green discloses a door having a composite construction with a conventional
perimeter
frame and a pair of molded fiberglass skins secured to the perimeter frame.
Within the
skins and the perimeter frame is a plastic foam core. U. S. Patent 5,438,808
to Costello
discloses a door having a perimeter frame, which is sandwiched between formed
metal
stampings or body panels. Wood panels or veneers may then be adhesively
secured to
the metal stampings to provide a wood appearance. Several different exterior
configurations are disclosed.
The present invention provides a door comprising a conventional perimeter
frame
and a pair of reverse molded wood composite skins. The molded skins include
asymmetrical configurations and fill elements between selected portions of the
skins.
The fill portions are disposed adjacent to the asymmetrical elements so as not
to interfere
with any warping of the asymmetrical elements due to temperature or humidity
conditions.
Summary of the Invention:
The present invention relates to a hollow core door comprising a perimeter
frame,
and first and second reverse molded door skins. Each of the skins has an
exterior surface
and an interior surface secured to opposing sides of the frame. At least one
of the skins
has an outer planar area, an inner planar area, and an asymmetric profile
surrounding the
inner planar area and interconnecting and integral with the outer planar area
and the inner
planar area. The asymmetric profile area has a convex portion extending
outwardly from
and relative to the plane of the outer planar area.
The present invention is also directed to a molded door skin comprising an
outer
planar area, an inner planar area, and an asymmetric profile area surrounding
the inner
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planar area and interconnecting and integral with the outer planar area and
the inner
planar area. The asymmetric profile area has a convex portion extending
outwardly from
and relative to the plane of the outer planar area.
A double skin door apparatus is provided, comprising a door frame having
opposing sides. A first door skin is secured to one side of the frame. The
first door skin
has a first asymmetrical profile including a convex portion and a concave
portion. A
second door skin is secured to an opposing side of the frame, and is spaced
from the first
door skin. The second door skin has a second asymmetrical profile including a
convex
portion and a concave portion. The convex portions of the first and second
door skins
define a first distance, and the concave portions of the first and second door
skins define
a second distance, wherein the first distance is greater than the second
distance. A plate
is disposed between the first and second door skins.
A door comprises a perimeter frame having a first face and a second face. The
frame has a first width. A first skin having a perimeter planar portion is
secured to the
first face of the frame. The first skin has an upper convex portion and an
upper inner
planar portion, a lower convex portion and a lower inner planar portion spaced
from the
upper convex portion and the upper inner planar portion. A second skin has a
perimeter
planar portion secured to the second face of the frame. The second skin has an
upper
convex portion and an upper inner planar portion, a lower convex portion and a
lower
inner planar portion spaced from the upper convex portion and the upper inner
planar
portion on the second skin. The upper convex portions of the first and second
skins and
the inner planar portions of the first and second skins are aligned with each
other.
Preferably the door skins are molded from a wood composite, such as medium
density
fiberboard, chip board, flake board, oriented strand board, and the like.
Objects of the present invention include the following: to provide a new and
useful door apparatus; to provide a new and useful interior door apparatus; to
provide a
new and useful door apparatus having a pair of exterior skins secured to a
perimeter
frame; to provide a new and useful door having a pair of asymmetrically
configured outer
skins secured to a frame; to provide a new and useful door apparatus including
a pair of
asymmetrically configured outer skins secured to a perimeter frame in a mirror
image
orientation; and to provide a new and useful door apparatus having a pair of
outer skins
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having asymmetrical elements secured to a perimeter frame and plates secured
to the
skins and disposed inwardly adjacent to the asymmetrical elements.
Detailed Description of the Figures:
Figure 1 is an elevational view of a door according to the present invention;
Figure 2 is a fragmentary cross-sectional view taken along line 2 - 2 of
Figure 1
and viewed in the direction of the arrows;
Figure 3 is an elevational view of a door according to a second embodiment;
and
Figure 4 is a fragmentary exploded view of a door according to a third
embodiment.
Detailed Description of the Invention:
As best shown in Figure 1, a door 10 comprises a perimeter frame 12, frame 12
having a pair of stiles 14, 16 and a pair of rails 18, 20. Rail 20 is disposed
near the top of
door 10, and rail 18 is disposed near the bottom of door 10. Stiles 14, 16 and
rails 18, 20
are appropriately secured together to define frame 12 of door 10. Frame 12 may
also
include an intermediate rail 22 disposed intermediate rails 18, 20 and
extending fully
between stiles 14, 16. Preferably, intermediate rail 22 extends parallel to
top and bottom
rails 18, 20. As well known in the art, a handle set (not shown) may be
secured to door
10 at intermediate rail 22. Rail 22 allows door 10 to be hung as either a
right hand or a
left hand door. Since rail 22 extends fully between stiles 14, 16, a handle
set maybe
secured to door 10 adjacent either stile 14 or stile 16.
Preferably, stiles 14, 16, rails 18, 20, and intermediate rail 22 are made of
wood or
wood product. Door 10 is particularly well suited as an interior door, and may
be
referred to as a hollow core door. Door 10 further comprises two skins 30, 50.
Each of
skins 30, 50 has an exterior visible surface 31, 51 and an interior surface
33, 53 for
securing to opposite sides of frame 12, as best shown in Figure 2. Skins 30,
50 may be
secured to frame 12 so that they are mirror images of each other.
Skin 30 includes an outer planar area 32. Inwardly from outer planar area 32
is an
asymmetrical profile P formed in skin 30. Asymmetrical profile P includes a
convex
portion 34 and a concave portion 36. The particular configuration of convex
portion 34
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and concave portion 36 may vary depending on consumer preference. Inwardly
from
concave portion 36 is an inner planar area 38. It can be seen from Fig. 2 that
the planar
areas 32 and 38 have a thickness exceeding the thickness of concave portion 34
and
convex portion 38. Therefore, inner planar area 38 is disposed within the
perimeter of
asymmetrical profile P and is inwardly spaced relative to planar portion 32.
That is,
asymmetrical profile P comprises a closed area relative to exterior surface
31. This
closed area may be either regular or irregular, depending on consumer
preference. For
example, asymmetrical profile P may define a rectangular closed area, or
asymmetrical
profile P may define a closed area having a curved side, as shown in Figure 1.
In either
case, asymmetrical profile P defines a continuous or closed loop, with inner
planar area
38 disposed within the closed loop.
Door 10 may include more than one asymmetrical profile portion P. For example,
door 10 shown in Figure 1 includes asymmetrical profile P defined by convex
portion 34
and concave portion 36, as described above. Asymmetrical profile P is disposed
in an
upper portion of door 10, preferably above intermediate rail 22 and below rail
20. In
addition, door 10 includes a second asymmetrical profile portion P2 disposed
below
intermediate rail 22 and above rail 18. Asymmetrical profile portion P2 may
have a
different closed loop configuration and shape compared to asymmetrical profile
portion
P. Asymmetrical profile P2 is defined by a lower convex portion 40 and a lower
concave
portion 42. Inwardly from lower concave portion 42 is a lower planar portion
44. Thus,
lower asymmetric profile P2 also comprises a closed loop, with convex portion
40 and
concave portion 42 comprising continuous elements.
The particular configuration of asymmetric profiles P, P2, or their connecting
elements, may vary from that illustrated in Figure 1 depending on consumer
preference.
While lower asymmetric profile P2 is shown as a square or a rectangle, upper
asymmetric
profile P is shown as an irregular shape with three straight sides and a
curved side. It
should be understood that any configuration or shape of an asymmetric profile
may be
formed in door skin 30. Furthermore, skin 30 may include any number of
asymmetric
profiles, thereby simulating multi-panel doors. In addition, skin 30 may
include a wood
grain pattern, as shown in Figure 1. As well known in the art, a wood grain
pattern may
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be embossed or formed in skin 30, or a veneer or paper overlay may be secured
to
exterior surface 31.
Skin 50 is substantially identical to skin 30, as best shown in Figure 2.
Thus, skin
50 includes an outer planar portion 52, an upper convex portion 54, an upper
concave
portion 56, and an upper inner planar portion 58 within an asymmetric profile
defined by
the convex portion 54 and the concave portion 56 and their connecting
elements. The
other portions of skin 50 may be understood from Figure 1 in that skin 50 is
essentially a
mirror image of skin 30. Thus, skin 50 may also include any configuration or
shape of
asymmetric profiles, but preferably corresponds to the configurations formed
in skin 30
so that convex and concave portions of skin 30 are aligned with convex and
concave
portions of skin 50, as shown in Figure 2. The use of double skins, with the
skins being
mirror images of each other, and both including asymmetric elements, provides
a door
that is stable under virtually all conditions of temperature and humidity, and
is also
aesthetically pleasing for consumers. Specifically, the asymmetry allows the
portion of
door 10 that is disposed inwardly from frame 12 to warp in response to
temperature and
humidity conditions without warping frame 12. In this way, frame 12 remains in
its
original planar configuration.
Skins 30, 50 are secured to opposing sides of frame 12 at the interior surface
33,
53 of outer planar areas 32, 52, respectively, and to the interior surface 33,
53
corresponding to an intermediate rail (or lock rail) 22. Skins 30 and 50 are
preferably
molded from a wood composite, such as medium density fiberboard. The skins 30
and
50 preferably are identical. In one embodiment of the present invention, a
plate element
70 is disposed between and secured to interior surface 33 of inner planar
portions 38, 58
of skins 30, 50, respectively, as best shown in Figure 2. Plate element 70
provides
stability to skins 30, 50 without hindering the warping of asymmetric profile
P adjacent
to the plate element 70. A second plate element 70 may also be disposed
between and
secured to interior surface 33 of lower inner planar portion 44 and the
corresponding
lower imier planar portion on skin 50. The asymmetric profiles P, P2 may warp
in
response to temperature and humidity conditions without affecting either
perimeter frame
12 or inner planar portions 38, 58 with their plate elements. And likewise,
inner planar
portions 38, 58 with plates 70 secured to them, do not affect the warping of
the
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asymmetric elements. Plates 70 provide additional strength and stability to
door 10,
regardless of the temperature and humidity conditions of the structure in
which the door
is installed. Plates 70 are formed from wood, wood composite, foam and like
materials
used to form a door core. The plate 70 is preferably adhesively secured to the
adjacent
door skins.
As best shown in Fig. 2, perimeter frame 12 has a predetermined width or
thickness, and the distance between convex portion 34 and convex portion 54,
shown by
arrow dl, is greater than the width of perimeter frame 12, shown by arrow d2.
The
distance between concave portions 36 and 56, shown by arrow d3, is less than
the width
of perimeter frame 12. The distance between inner planar portion 38 and inner
planar
portion 58 (with plate 70 disposed between them), shown by arrow d4, is less
than the
distance between convex portions 34 and 54 (dl), but is greater than the
distance between
concave portions 36 and 56 (d3). Also, it can be seen from Fig. 2 that the
plate 70
secured to skins 30 and 50 is longitudinally spaced from rail 14, thus
providing a hollow
space encompassing planar portions 32, convex portions 34, and concave
portions 36.
In addition, the caliper of skin 30 at convex portion 34 is less than the
caliper of
skin 30 at outer planar area 32 or inner planar area 38. Convex portion 34
extends
outwardly beyond the plane of outer planar area 32 relative to exterior
surface 31.
Concave portion 36 extends inwardly from the plane of outer planar area 32
relative to
exterior surface 31. Inner planar area 38 lies on a plane spaced from the
plane of outer
planar area 32, and is preferably recessed from outer planar area 32, as shown
in Figure
2. Concave portion 36 may also extend inwardly from the plane of inner planar
area 38,
creating a relatively small distance d3 between concave portions 36, 56, as
noted above.
Similarly, the caliper of skin 50 at convex portion 54 is less than the
caliper of
skin 50 at outer planar area 52 or inner planar area 58. Convex portion 54
extends
outwardly beyond the plane of outer planar area 52 relative to exterior
surface 51.
Concave portion 56 extends inwardly from the plane of outer planar area 52
relative to
exterior surface 51. Inner planar area 58 lies on a plane spaced from the
plane of outer
planar area 52, and is/ preferably recessed from outer planar area 52. Concave
portion 56
may also extend inwardly from the plane of inner planar area 58, as with
concave portion
36 and thereby defining distance d3.
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The configuration and alignment of the lower asymmetric profile P2, with
respect
to the convex and concave portions, is substantially the same as that
discussed above for
the upper asymmetric profile P with respective convex and concave portions,
and the
inner planar portion with its plate, aligned accordingly. It should be
understood that the
configuration of lower asymmetric profile P2 may vary depending on consumer
preference.
As best shown in Figure 3, a second embodiment of the present invention
provides for a door 110 having a perimeter frame 112, and a plurality of upper
asymmetric elements 134, 144 and inner planar elements 140, 150, a plurality
of
intermediate asymmetric elements 154, 164 and inner planar elements 160, 170,
and a
plurality of lower asymmetric elements 174, 184 and inner planar elements 180,
190.
Perimeter frame 112 includes a pair of vertical stiles 114, 116 and a pair of
horizontal
rails 118, 120. Door 110 may also include an intermediate rail 122 extending
between
stiles 114, 116 and appropriately secured thereto. A pair of skins 130 are
appropriately
secured to opposing sides of perimeter frame 112 and to intermediate rail 122,
as
described above for door 10. Although only one skin 130 is shown in Figure 3,
it should
be understood that a second skin is secured to the opposite side of frame 112,
and is
preferably a mirror image of skin 130 just as skin 50 is preferably a mirror
image of skin
30 on door 10. Each of skins 130 is manufactured from a molded wood composite,
such
as medium density fiberboard.
Each of skins 130 includes a perimeter planar area 132, which may be secured
to
perimeter frame 112. Skin 130 includes a pair of upper asymmetric profiles
134, 144, a
pair of intermediate asymmetric profiles 154, 164, and a pair of lower
asymmetric
profiles 174, 184. Note that asymmetric profiles 134, 144, 154, 164, 174 and
184 may
differ in size and shape. For example, as shown in Figure 3, upper asymmetric
profiles
134, 144 are smaller than intermediate and lower asymmetric profiles 154, 164,
and
174,184, respectively. The differences in size and shape are for illustrative
and
explanatory purposes only, and are immaterial to the functionality of door
110.
As described above for door 10, each asymmetric profile on door 110 includes a
closed loop convex portion integral with and connected to a closed loop
concave portion.
Each concave portion is disposed about an inner planar portion. For example,
profile 134
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includes a closed loop convex portion 136 connected to a closed loop concave
portion
138, and an enclosed inner planar portion 140. Profile 144 includes a closed
loop convex
portion 146 connected to a closed loop concave portion 148, and an enclosed
inner planar
portion 150.
Intermediate asymmetric profiles 154, 164 include, respectively, closed loop
convex portions 156, 166, integral with and connected to closed loop concave
portions
158, 168, and enclosed inner planar portions 160, 170. Lower asymmetric
profiles 174,
184 include closed loop convex portions 176, 186, integral with and connected
to closed
loop concave portions 178, 188, and disposed about or enclosing inner planar
portions
180, 190, respectively.
As shown in Figure 3, the closed loop asymmetric profiles are of a generally
elongated rectangular configuration. However, the profile configurations of
door 110
may have any desired size and shape, depending on consumer preference. For
example,
the asymmetric profiles may be round, square, rectangular, irregular, or a
combination of
such shapes (as in asymmetric profile P in Figure 1). In order to allow for
appropriate
warping of door 110, without distorting or warping perimeter frame 112, the
profiles
need only be closed loop. Each profile includes a convex portion, a concave
portion
connected to the convex portion, and an enclosed inner planar portion.
Preferably, the opposing skins 130 are secured to frame 112 so that skins 130
have a mirror image when viewed in cross-section (as shown in Figure 2 for
door 10).
Skins 130 are therefore secured to frame 112 in a similar manner as described
above for
door 10. Furthermore, door 110 may also include plates secured between the
pair of
skins 130 between the enclosed inner planar portions 140, 150, 160, 170, 180,
190 and
corresponding inner planar portions of the other skin 130 securing to the
opposing side of
frame 112, as discussed above. Furthermore, door 110 may also include a wood
grain
pattern, as shown in Figure 3.
As best shown in Figure 4, a third embodiment of the present invention
provides
for a door 210 having a lock block 222 secured to a stile 214, as opposed to
an
intermediate rail or lock rail extending fully between the vertical stiles (as
in doors 10
and 110). A second lock block (not shown) may be secured to the opposing stile
on the
opposite side of door 210. Except for the omission of an intermediate rail
extending fully
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between opposing stiles, and the inclusion of at least one lock block 222, the
configuration of door 210 is identical to that described for doors 10 and 110.
With two
lock blocks, door 210 may have a lock set secured on either side of door 210.
Therefore, door 210 includes a full perimeter frame 212, which includes stile
214
to which block 222 is secured. A pair of outer skins 230, 250 are secured to
opposing
sides of frame 212. For purposes of discussion, skin 230 is a "front" skin,
and skin 250 is
a "rear" skin. Skins 230, 250 are mirror images of each other, as discussed
for doors 10
and 110. Skin 230 includes an outer perimeter planar area or portion 232, and
skin 250
includes an outer perimeter planar area or portion 252. Outer perimeter
portions 232, 252
are appropriately secured to frame 212 and to the lock block 222, as well as a
lock block
opposite lock block 222 on the opposing stile (not shown).
The asymmetrical design or portion for skin 230 includes a convex portion 234
and a concave portion 236, as described above. The asymmetrical design or
profile for
skin 250 includes a convex portion 254 and a concave portion 256. The
respective
convex and concave portions of the skins are aligned with each other, as
discussed above
and as illustrated for the door 10 in Figure 2.
The convex and concave portions extend continuously, without a break, for the
full length of skins 230, 250, and are disposed inwardly from outer perimeter
portions
232, 252, respectively. The convex and concave elements therefore provide
relatively
long closed loops compared to the shorter closed loops of doors 10 and 110.
Without a
transversely extending intermediate or lock rail, door 210 may have such full-
length
asymmetric portions in skins 230, 250.
Each skin 230, 250 includes an inner planar area adjacent to concave portions
of
the skins, as described above. For example, skin 230 includes an inner planar
portion 238
and skin 250 includes an inner planar portion 258. A plate 270 may be secured
between
inner planar portions 238, 258. Plate 270 provides stability for door 210, as
explained
above. Plate 270 may extend fully within the asymmetrical profile of door 210,
adjacent
concave portions 236, 256, without restricting warping of the aligned
asymmetrical
portions in response to temperature and humidity conditions.
Certain aspects of the present invention have been explained with respect to
specific embodiments. However, it will be apparent to one of ordinary skill in
the art that
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various modifications and variations can be made in construction or
configuration of the
present invention without departing from the scope or spirit of the invention.
Therefore,
it is intended that the present invention cover all such modifications and
variations,
provided they come within the scope of the following claims and their
equivalents.
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