Note: Descriptions are shown in the official language in which they were submitted.
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TITLE OF THE INVENTION
DRYWALL TOOL
FIELD OF THE INVENTION
[0001] The present invention relates to a tool for cutting drywall.
BACKGROUND OF THE INVENTION
[0002] Drywall is an essential component in conventional building
construction. The skeleton of an interior room in a building includes vertical
corner posts which bookend upright supports, known as studs. The studs
constitute the structural support for the non-load bearing walls in a
building.
Sheets of drywall are attached to the opposing sides of studs and extend from
floor to ceiling.
[0003] Vertical corner posts are normally metallic and recently metal studs
have gained acceptance amongst builders. As a result, these components of a
building's construction are fire-resistant. The drywall is also fire-
resistant, which
helps to contain a fire within a single room. To ensure that the fire is
contained,
the boundaries between the ceilings and the walls must be well sealed.
[0004] Sealing the boundary between a wall and the ceiling of a room is
particularly challenging when the ceiling is fluted decking. Normally,
concrete is
poured onto fluted decking to form the floor above. The decking itself is
steel
with downwardly facing, concave channels and may be left exposed for cosmetic
reasons. The channels are also known as flutes.
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[0005] The decking extends along the length of a building such that the
walls of individual rooms meet the decking transversely. Where the walls
extend
along the length of a channel, there will be little potential for gaps at the
meeting
points. However, where the plane of the wall is transverse from the planes of
the channels, there will be gaps where the walls meet the decking unless the
drywall is cut or shaped to fit within the channels.
[0006] Recently there has been a trend toward attempting to prevent the
spread of fire beyond interior walls by adding strict provisions to fire code
regulations. Fire-resistant insulation is packed in the flute openings between
rooms to prevent the spread of flames. If the gap between the drywall and the
roof flutes is not properly sealed, expensive fire retardant spray must be
applied
to the insulation. Even after fire-retardant spray is applied, there are
significant
risks. When a fire is burning in a room, the smoke generated by the fire
creates
pressure. This pressure has been known to force the insulation from its
placement between the walls, thus opening a passage for the spread of flames.
[0007] Therefore, to secure the insulation within the cavity between the
walls, fire code regulations now require the precise cutting of drywall so
that its
top edge fits within the deck flutes. Hand cutting the top edge of the drywall
can
be labour intensive and may add significantly to the costs of construction.
Furthermore, hand cutting frequently results in the drywall fitting poorly at
the
border of the deck flutes and the interior walls. Extensive caulking or the
addition of fire tape at the gap between the drywall and the ceiling will then
be
necessary.
SUMMARY OF THE INVENTION
[0008] In view of the deficiencies of the prior art, a tool is provided for
use
in cutting varied lengths of drywall sheets to match the profile of a surface
against which the drywall is to be mounted.
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[0009] Accordingly, in one aspect of the invention, an apparatus is
comprised of a plate with a bottom edge, a top edge, a first side edge and a
second side edge. The plate has at least one indentation on its top edge
between the first side edge and the second side edge. The apparatus can be
placed flush against drywall such that the drywall may be cut with
indentations
matching the at least one indentation in the top edge of the plate.
[0010] In a further aspect of the invention, the apparatus is comprised of a
plurality of plates joined together. Each of the plates has a bottom edge, a
top
edge, a first side edge and a second side edge. Each of the plates also has at
least one indentation on its top edge between the first side edge and the
second
side edge. The apparatus can be placed flush against dryv,rall such that the
drywall may be cut with indentations matching the at least one indentation in
the
top edge of each of the plates.
[0011] A further aspect of the invention is a method for cutting drywall
using a plate with at least one indentation in a top edge of the plate and
comprising the steps of placing the plate against the drywall and cutting the
drywall to match the at least one indentation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The invention is best understood from the following detailed
description when read in connection with the accompanying drawings. It is
emphasized that, according to common practice, the various features of the
drawings are not to scale. On the contrary, the dimensions of the various
features are arbitrarily expanded or reduced for clarity. Included in the
drawings
are the following Figures:
[0013] Figure 1 is a perspective view of a first exemplary embodiment of
the invention with one plate;
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[0014] Figure 2 is a perspective view of a second exemplary embodiment of
the invention with two plates in an open position;
[0015] Figure 3 is a perspective view of the second embodiment of the
invention with two plates in a closed position;
[0016] Figure 4a is a cross-sectional view of the second embodiment of the
invention, taken along line 4a-4a of Figure 2, with a fastener in a tightened
position;
[0017] Figure 4b is a cross-sectional view of the second embodiment of the
invention, taken along line 4a-4a of Figure 2, with the fastener in a loosened
position;
[0018] Figure 5 is a perspective view of the second embodiment of the
invention with two plates apart from one another;
[0019] Figure 6 is a perspective view of a third exemplary embodiment of
the invention;
[0020] Figure 7 is a top view of the third embodiment of the invention with
a fastener in a tightened position; and
[0021] Figure 8 is a perspective view of the second embodiment of the
invention in situ relative to a partially cut sheet of drywall below a roof
with deck
flutes.
DETAILED DESCRIPTION
[0022] A drywall tool 10 for cutting drywall is shown in Figure 1. The
drywall tool 10 is generally comprised of a plate 12. The plate 12 is
desirably
substantially flat. Furthermore, the plate 12 may be comprised of any solid
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material. In one exemplary embodiment of the apparatus, the plate is metallic.
A light yet durable metal such as aluminum is desirable. The plate 12 may be
constructed in a variety of dimensions to suit the application. One
configuration
found suitable for cutting drywall for abutting ceiling deck flutes is for the
plate
12 to be one quarter inch thick, three inches high and fifty inches long.
[0023] The plate 12 has a bottom edge 14, a top edge 16, a first side edge
18 and a second side edge 20. The bottom edge 14 is parallel to the top edge
16
of the plate 12. The first side edge 18 and the second side edge 20 are
parallel
to one another and perpendicular to bottom edge 14 and top edge 16 of the
plate 12. The plate 12 has indentations 22 in the top edge 14. In one
exemplary embodiment of the drywall tool 10, each of the indentations 22 has
opposing sloped edges 24. The sloped edges 24 meet at an indentation floor 26.
Each indentation floor 26 is parallel to the bottom edge 14 and the top edge
16
of the plate 12. Furthermore, each indentation floor 26 is equidistant from
the
bottom edge 14 of the plate 12.
[0024] In the configuration of the drywall tool 10 shown and discussed
herein, the indentations 22 are spaced three inches apart and the indentation
floor 26 is one and one half inches long. However, as the skilled person in
the
art will appreciate, the spacing of the indentations 22 and the length of the
indentation floor 26 may vary. The plate 12 may be manufactured such that the
indentations 22 may match any profile against which the drywall tool 10 is
placed. Furthermore, the plate 12 may be manufactured such that the drywall
tool 10 fits snugly against roof flutes of any dimension.
[0025] In a further embodiment of the invention, shown in an open position
in Figure 2, the plate 12 is joined to a second plate 28. The second plate 28
has
dimensions identical to the dimensions of the plate 12 and has a first side
edge
34, a bottom edge 36 and a top edge 38.
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[0026] In this embodiment of the invention, the plate 12 has a first
aperture 30 and the second plate 28 has a second aperture 32 (as best seen in
Figure 5). Desirably, the first aperture 30 extends through the entire
thickness
of plate 12 and the second aperture 32 extends through the entire thickness of
the second plate 28. However, one of the first aperture 30 and the second
aperture 32 may not extend through the entire thickness of the corresponding
plate. In this circumstance, the aperture that does not extend through the
entire
plate is threaded to accept a threaded fastener.
[0027] It will be appreciated by those skilled in the art that more than two
of plates 12, 28 can be joined together to form a length of tool 10 suitable
for
cutting drywall. The embodiment of the two plates 12, 28 will be illustrated
and
discussed for convenience.
[0028] As illustrated, the first aperture 30 is proximate to the second side
edge 20 of the plate 12 and the second aperture 32 is proximate to the first
side
edge 34 of the second plate 28. Furthermore, the distance between the first
aperture 30 and the second side edge 20 and the distance between the second
aperture 32 and the first side edge 34 are such that when the first aperture
30 is
lined up with the second aperture 32, the edges 20, 34 overlap such that the
resulting distance between an indentation 40 closest to the second side edge
20
and an indentation 42 closest to the first side edge 34 is equal to the
distance
"d" between indentations 22 in each of the plates 12, 28.
(0029] As shown in Figure 4a, when the first aperture 30 is lined up with
second aperture 32, a fastener 44 may be placed through the first aperture 30
and the second aperture 32 to releasably join the plate 12 and the second
plate
28. The fastener 44 may be a peg, a bolt, a screw or any other elongated
device
sized to extend through the first aperture 30 and the second aperture 32. The
fastener 44 is threaded and releasably secured in place by a nut 46.
Desirably,
the nut 46 has head 48 that may be easily gripped by the user of the drywall
tool
10. Conventional nuts, including wingnuts, may also be used.
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[0030] Alternatively, if one of the first aperture 30 or the second aperture
32 does not extend through the plate 12 or the second plate 28, respectively,
that aperture is threaded. The fastener 44 is sized to extend through the non-
threaded aperture and engage the threaded aperture in order to releasably
secure the fastener.
[0031] A recess 50 in the plate 12 surrounds the first aperture 30, as
shown in Figure 5. In one exemplary embodiment, the recess 50 has a bottom
52, a top 54, a first side 56 and a second side 58. The bottom 52 is parallel
to
the top 54 and the bottom 52 and the top 54 are perpendicular to the first
side
56 and the second side 58 such that the recess 50 is square shaped or
rectangular. Furthermore, the bottom 52 and the top 54 of the recess 50 are
both parallel to the bottom edge 14 and the top edge 16 of the plate 12. The
depth x of recess 50 is equal to half of the thickness y of the plate 12.
[0032] A flange 60 surrounds the second aperture 32. In one exemplary
embodiment, the flange 60 has a bottom 62, a top 64, a first side 66 and a
second side 68. The bottom 62 is parallel to the top 64 and the bottom 62 and
the top 64 are perpendicular to the first side 66 and the second side 68 such
that
the flange 60 is square shaped or rectangular. Furthermore, the bottom 62 and
the top 64 of the flange 60 are both parallel to the bottom edge 36 and the
top
edge 38 of the second plate 28. The thickness z of the flange 60 is equal to
half
of the thickness y of the second plate 28.
[0033] The recess 50 and the flange 60 are oriented and sized such that
when the first aperture 30 is lined up with the second aperture 32 the recess
50
receives the flange 60. Furthermore, the height and width of the flange 60 are
each only slightly less than the height and width of the recess 50,
respectively,
such that the flange 60 fits tightly within the recess 50.
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[0034] In a further embodiment (not shown) the recess 50 and the flange
60 are both circular.
[0035] In a further alternative embodiment of the invention shown in
Figures 6 and 7, the plate 12 has a cutout 78 and the second plate 28 has a
second cutout 80. The depth m of the cutout 78 is equal to half the thickness
n
of the plate 12. The depth o of the second cutout 80 is equal to half of the
thickness n of the second plate 28. The cutout 78 surrounds the first aperture
30 and extends between the bottom edge 14 and the top edge 16 of the plate
12. Similarly, second cutout 80 surrounds the second aperture 32 and extends
between the bottom edge 36 and the top edge 38 of the second plate 28. The
cutout 78 and the second cutout 80 are mirror images of one another.
[0036] The drywall tool 10 comprised of plate 12 and second plate 28 has
an open position, shown in Figure 2 and a closed position, shown in Figure 3.
To
manipulate the drywall tool 10 between these two positions, the nut 46 is
loosened by rotating the nut 46 about the fastener 44. The plate 12 is
separated
from the second plate 28 such that the flange 60 is no longer nested within
the
recess 50, as shown in Figure 4b. The plate 12 or the second plate 28 may then
be rotated one hundred and eighty degrees about the fastener 44 to the open
position or the closed position, the plates may be pressed together such that
the
flange 60 nests within the recess 50 as shown in Figure 4a and the nut 46 may
be tightened.
[0037] Alternatively, if the recess 50 and the flange 60 are circular, the
user does not have to separate the plate 12 from the second plate 28 before
rotating the plate 12 or the second plate 28 about the other.
[0038] When using the drywall tool 10 for cutting, the drywall tool 10 is
placed against a piece of drywall 70. The length of the drywall 70 to be cut
will
determine whether the tool 10 will comprise a single plate 12, a plate 12 and
a
second plate 28, or three or more properly oriented plates. The drywall tool
10
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may be releasably attached to a piece of drywall by at least one securing
means
72, as shown in Figure 8. The securing means 72 may be a clamp or a clip or
anything suitable to hold the tool 10 flush against the drywall 70. When the
flange 60 is tightly nested in the recess 50 and the drywall tool 10 is in the
open
position, each of the indentation floors 26 of the plate 12 and the second
plate
28 will be equidistant from the top edge of the drywall 70. The drywall 70 is
then cut to the shape of the drywall tool 10 such that a resulting profile of
a top
edge 74 of the drywall 70 fits within fluted roof decking 76. Alternatively,
an
outline of the drywalling tool 10 may be traced upon the drywall 70 and the
drywall tool 10 may be detached from the drywall 70 before cutting the drywall
70 along the tracings.
[0039] Numerous modifications may be made to the embodiments as
described above without departing from the scope of the invention, which is
described by the claims.
