Note: Descriptions are shown in the official language in which they were submitted.
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UNILATERAL SCAFFOLD SYSTEM
BACKGROUND OF THE INVENTION
The present invention relates generally to a scaffold system. More
particularly, the present invention relates to a scaffold system that is
attachable to
a wall.
When performing commercial and residential construction, it is
commonly necessary to use scaffolding to provide workers access to areas where
the work is to be preformed. Many types of scaffolding have-been developed to
accommodate these situations. For example, Allenbaugh, U.S. Patent No.
4,891,926, discloses a scaffolding system that permits a person to walk
beneath the
scaffold. Each =scaffold frame includes a pair of triangular-shaped support
members
and a connecting crosspiece. Allenbaugh = indicates that the triangular-shaped
support members are separable from the connecting crosspiece so as to enable
the
scaffold frame to be carried through narrow openings.
Chez, U.S. Patent No. 4,262,774, describes an adjustable
scaffolding system in which a support piatform is slidably mounted to legs.
Sliding
the support platform with respect to the legs allows the height of the
sc:affold to be
adju9ted. Each of the legs includes a wheel, which enables the scaffold to be
moved along the ground. Helsper, U.S. Patent No. 4,947,962, describes an
adjustable scaffolding support that is in the shape of the letter "Ap.
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Gostling, U.S. Patent No. 3,656,580, discloses a scaffolding system
in -.A,hich the legs closest to a building wall are attached to the wall. The
legs
opposite the wall are supported through the ground using an adjustable base.
To avoid the difficulties of preparing the ground to adequately
support a scaffolding system in a stationary position with respect to a
building,
scaffolding systems have been developed that permit the scaffolding system to
be
attached to the building wall. For example, Savitski, U.S. Patent No.
5,535,974,
describes a scaffold bracket having first and second grippers, which extend
around
opposite sides of a stud. A downward force on an end of the scaffold bracket
opposite the first and second grippers causes the first and second grippers to
engage
the stud.
St-Germain, U.S. Patent No. 4,850,453, utilizes a plate imbedded in
the mortar of a brick or concrete wall. The scaffold is attached to the plate
during
construction. After construction is completed, the scaffold is unattached from
the
plate and the portion of the plate extending from wall is removed.
Flathau et al., U.S. Patent No. 5,316,253, discloses a triangular-
shaped scaffold bracket. The scaffold bracket includes a plank support leg and
an
attachment leg. The attachment leg includes a plurality of pear-shaped slots
that are
each adapted to receive a fastening device, such as a bolt, for removably
attaching
the scaffold bracket to a wall.
Yennie, Jr., U.S. Patent No. 5,524,727, describes a construction wall
bracket that hangs over the top of a wall. The bracket includes a vertical
member
and a swing arm that is pivotably attached to the top of the vertical member
so that
the swing arm can extend over the top of the wall. The bracket also includes a
horizontal member that extends perpendicularly outward from the vertical
member.
Yennie, Jr. indicates that the bracket is used during construction of raflers,
ceiling
joists, or a roof.
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SUMMARY OF THE INVENTION
The present invention is a scaffold system for removable attachment to a wall.
The scaffold system includes a vertical support member, a horizontal support
member,
and an attaching bracket.
The vertical support member has a first end and a second end. The horizontal
support member has a first end and a second end. The first end of the vertical
support
member is attached to the horizontal support member so that the vertical
support
member is substantially perpendicular to the horizontal support member.
The attaching bracket extends from the horizontal support member substantially
aligned with and parallel to the horizontal support member. The attaching
bracket
removably attaches the support member and the horizontal support member to the
wall.
According to a first broad aspect of an embodiment of the present invention,
there is disclosed a scaffold system for removable attachment to a support
structure, the
scaffold system comprising: a vertical support member having a first end and a
second
end; a horizontal support member having a first end and a second end, wherein
the first
end of the vertical support member is attached to the horizontal support
member so that
the vertical support member is substantially perpendicular to the horizontal
support
member; an attaching bracket port attached to the horizontal support member;
and
an attaching bracket extending from the horizontal support member, the
attaching
bracket comprising: an extension arm having an outer profile that is
substantially the
same as an inner profile of the attaching bracket port such that the extension
arm is
slidable through the attaching bracket port; and a nail plate attached to the
extension
arm substantially perpendicular to the extension arm, and wherein the nail
plate is
adapted to engage the support structure for removably attaching the vertical
support
member and the horizontal support member to the support structure.
According to a second broad aspect of an embodiment of the present invention,
there is disclosed a scaffold system for removable attachment to a vertically-
oriented
wall, the scaffold system comprising: a vertical support member having a first
end and a
second end; a horizontal support member having a first end and a second end,
wherein
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the first end of the vertical support member is attached to the horizontal
support
member so that the vertical support member is substantially perpendicular to
the
horizontal support member; an attaching bracket port attached to the
horizontal support
member; and an attaching bracket comprising: an upper portion comprising: an
extension arm having an outer profile that is substantially the same as an
inner profile of
the attaching bracket port such that the extension arm is slidable through the
attaching
bracket port; and a bracket attached to the extension arm, wherein the bracket
is adapted
to engage the vertically-oriented wall; and a lower portion that engages the
scaffold
system proximate a lower end of the vertical support member, and wherein the
lower
portion is adapted to engage the vertically-oriented wall.
According to a third broad aspect of an embodiment of the present invention,
there is disclosed a scaffold system for removable attachment to a ladder, the
scaffold
system comprising: a vertical support member having a first end and a second
end;
a horizontal support member having a first end and a second end, wherein the
first end
of the vertical support member is attached to the horizontal support member so
that the
vertical support member is substantially perpendicular to the horizontal
support
member; an attaching bracket port attached to the horizontal support member;
and
an attaching bracket comprising: an upper portion comprising: an extension arm
having
an outer profile that is substantially the same as an inner profile of the
attaching bracket
port such that the extension arm is slidable through the attaching bracket
port; and a
bracket attached to the extension arm, wherein the bracket is adapted to
engage an
upper rung on the ladder; and a lower portion that engages the scaffold system
proximate a lower end of the vertical support member, wherein the lower
portion is
adapted to engage a lower rung on the ladder, and wherein the lower portion is
longer
than the upper portion so that the lower end of the vertical support member is
maintained further away from the ladder than an upper end of the vertical
support
member when the scaffold system is attached to the ladder.
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BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a perspective view of a scaffold system according to the present
invention.
Figure 2 is a sectional view illustrating the attachment of the scaffold
system to
the wall.
Figure 3 is a perspective view of an attaching bracket of the scaffold system.
Figure 4 is a sectional view of an outrigger used with the scaffold system.
Figure 5 is a perspective view of the outrigger.
Figure 6 is a perspective view of a vertical extension frame for use with the
scaffold system.
20
30
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Figure 7 is a sectional view of a height extension used with the
scaffold system.
Figure 8 is a perspective view of a support rail for use with the
scaffold system.
Figure 9 is a perspective view of an attachment adapter for use with
the scaffold system.
Figure 10 is a perspective view of an alternative attaching bracket
used with the scaffold system.
Figure 11 is a top view of a top portion of the attaching bracket
illustrated in Figure 10.
Figure 12 is a top view of a bottom portion of the attaching bracket
illustrated in Figure 10.
Figure 13 is a side view of the bottom portion of the attaching
bracket illustrated in Figure 10.
Figure 14 is a side view of yet another altemative attaching bracket
used with the scaffold system.
Figure 15 is a top view of a bonom portion of the attaching bracket
illustrated in Figure 14.
Figure 16 is a top view of a lower attaching bracket for the scaffold
system illustrated in Figure 14.
Figure 17 is a sectional view of a plank mounting bracket for use
with the scaffold system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is a scaffold system, as most clearly
illustrated at 10 in Figures 1 and 2. The scaffold system 10 may be readily
attached
to a support structure. One preferred support structure is a wall 12. The
scaffold
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system 10 may be attached from either the inside of the wall 12 or the outside
of the
wall 12. The scaffold system 10 does not require a stable ground surface to be
prepared for erecting the scaffolding. Additionally,the scaffold system 10
does not
interfere with mounting of wall board sheathing or siding on the wall 12.
The scaffold system 10 generally includes a vertical support
member 20 and a horizontal support member 22, which is attached to and extends
from the vertical support member 20. As used herein, the terms "vertical" and
"horizontal" refer to a pref~rred orientation of the identified components
when the
scaffold system 10 is removably attached to the wall 12. Use of the terms
"vertical"
and "horizontal" is not intended to limit the scope of the present invention
but
rather to assist in visualizing the configuration and use of the scaffold
system 10.
The vertical support member 20 is mounted to the horizontal
support member 22 so that the vertical support member 20 is substantially
perpendicular to the horizontal support member 22. Accordingly, the
combination
of the vertical support member 20 and the horizontal support member 22 is
substantially in the shape of the letter "L".
The vertical support member 20 is preferably in the shape of the
letter "L" where each of the legs of the "L" shape have a length of between
about
1'/2 and 2 inches and a thickness of approximately 1/8 of an inch. The
vertical
support member 20preferably has a length of between about 24 and 36 inches.
Unless specified otherwise, all components of the scaffold system
are fabricated from a metallic material, such as steel or aluminum. A person
of
ordinary skill in the art will appreciate that when all of the components are
formed
from metallic materials that the components may be welded together or fastened
together with bolts and nuts.
The horizontal support member 22 preferably has a substantially
square profile with a width of between about 2 and 3 inches and a thickness of
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approximately Ma of an inch. The horizontal support member 22 is selected with
a length that corresponds with a distance that is desired to be away from the
wall 12
to which the scaffold system 10 is attached. Preferably, the horizontal
support
member 22 has a length of between about 24 and 36 inches.
The scaffold system 10 also preferably includes an angle brace 24
that is oriented at an angle with respect to the vertical support member 20
and the
horizontal support member 22. The angle brace 24 is preferably attached
proximate
to an end 30 of the vertical support member 20 that is opposite the horizontal
support member 22. Similarly, the angle brace 24 is preferably attached
proximate 10 to an end 32 of the horizontal support member 22 that is opposite
the vertical
support member 20.
The scaffold system 10 also includes a cross brace 36 attached to
the vertical support member 20 proximate to the end 30. The cross brace 36
increases the surface area over which an inward force is applied to the wall
12 when
weight is placed upon the scaffold system 10. The cross brace 36 is preferably
oriented substantially perpendicular to the vertical support member 20. While
the
cross brace 36 is not attached to the horizontal support member 22, the cross
brace
36 is preferably oriented substantially perpendicular to the horizontal
support
member 22.
The length of the cross brace 36 is selected based on the spacing
between vertically oriented studs 16 in the wall 12 so that the cross brace 36
extends between adjacent studs 16. When studs 16 are spaced so that the center
of
each stud 16 is approximately 16 inches apart, the cross brace 36 is
preferably
selected with a length of at least 2 feet. '
The scaffold system 10 further includes an attaching bracket 40 that
slidably engages the horizontal support member 22 by sliding into attaching
bracket
port 47. The attaching bracket 40 preferably includes an extension arm 42. The
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extension arm 42 is preferably selected with an outer profile which is
approximately the
same as an inner profile of the attaching bracket port 47. The extension arm
42 is
thereby slidable inside of the attaching bracket port 47 in a direction that
is
substantially aligned with and parallel to the horizontal support member 22.
The extension arm 42 includes a plurality of spaced-apart apertures
41; extending therPrl,rrõvgt,, as =nost clearly iiltistrated in Figt-rP Z e
nP*crn mf
ordinary skill in the art will appreciate that the extension arm 42 may be
formed
with a large number of apertures 46 to permit the scaffold system 10 to be
used
with walls 12 having a variety of thicknesses by orienting the apertures 46 in
other Telationships, such as placing the apertures 46 at intervals of
approximately
2 inches. The placement of the extension arm apertures 46 preferably permits
the
scaffold system ] 0 to be used with walls 12 having thicknesses of between
approximately 4 inches and 8 inches for use with masonry walls.
Proximate to an end of the horizontal support member 22 that is
] 5 attached to the vertical support member 20, the attaching bracket port 47,
which is
welded to the underside of the horizontal support member 22 includes an
aperture
48 extending therethrough, as most clearly illustrated in Figures I and 2. The
attaching bracket port 47 is oriented so that sliding of the extension arnz 42
with
respect to the attaching bracket port 47 allows one of the extension arm
apertures
46 to be aligned with the horizontal support aperture 48. Alignment of one of
the
extension arm apertures 46 with the horizontal support aperture 48 allows a
pin 49
to be extended therethrough to thereby retain the extension ann 42 in a fixed
relation with respect to the horizonta) support member 22.
The att.aching bracket 40 also preferably includes a nail plate 52
attached to the extension arm 42 so that the nail plate 52 is oriented
substantially
perpendicular to the extension arm 42. The nail plate 52 is preferably in the
shape
of the letter "L" and has a length of approximately 8 inches.
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The nail plate 52 preferably includes at least one aperture 54 that
extends through a leg 53 of the nail plate 52 that is attached to extension
arm 42.
The aperture 54 is selected with a diameter that permits a nail or screw to
pass
therethrough. Using a nail or screw with the nail plate 52 allows the nail
plate 52
to be retained in a desired location on the sill plate 14.
Jn an alternative embodiment, the attaching bracket 40 includes a
threaded portion 44 that extends from an end of the extension arm 42 opposite
the
end of the extension arm 42 having the apertures 46, as most clearly
illustrated in
Figure 3. With this configuration, the nail plate 52 includes an aperture 58
that
extends through the leg 53. The aperture 58 is formed with a sufficient
diameter
to permit the threaded portion 44 to extend therethrough. The attaching
bracket 40
in this configuration also includes a threaded nut 62 that threadably engages
the
threaded portion 44 and thereby retains the extension arm 42 in a fixed
retationship
ith respect to the nail plate 52.
When using this configuration of the anaching bracket 40, the
scaffold system 10 is suitable for attachment at an intermediate location
between
a top and bottom of the wall 12, as most clearly illustrated in Figure 4.
Using the
scaffold system 10 in this configuration also permits work to be done on the
portions of the building that do not offer a conventional plate for access to
certain
portions of the building from the scaffold system 10. In this configuration,
the nail
plate 52 has a length of at least 26 inches and preferably greater than 30
inches.
The scaffold system 10 preferably includes a mounting bracket 60
attached to the horizontal support member 22 proximate to the end 32 that is
opposite the vertical support member 20, as most ciearly illustrated in
Figures 1 and
2. The mounting bracket 60 is adapted to receive a coupling pin 65, which
allows
a railing 70 to be removably attached to the scaffold system 10, as most
clearly
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illustrated in Figures 2 and 8. The railing 70 protects persons working on the
scaffold from falling off the scaffold.
The coupling pin 65 has a substantially square profile and includes
end portions 67 that extend from opposite ends of a middle portion 69, as most
clearly illustrated in Figure 9. The outer surface of the end portions 67 is
approximately the same size as an inner surface of the mounting bracket 60 so
that
it is possible for the end portion 67 to slide inside of the mounting bracket
60. The
wider middle portion 69 limits the distance to which the coupling pin 65 is
insertable into the mounting bracket 60.
The scaffold system 10 includes the ability to use an outrigger 72,
as most clearly illustrated in Figures 4 and 5. Using the outrigger 72 with
the
scaffold system 10 allows a person to perform work located at a greater
distance
from the wall 12, such as a buildingoverhang 83. The outrigger 72 preferably
has
a square profile where an outer profile of the outrigger 72 is approximately
the
same size as an inner profile of the horizontal support member 22. The
outrigger
72 is thereby slidable inside of the horizontal support member 22 in a
direction that
is substantially aligned with and parallel to the horizontal support member
22.
The outrigger 72 includes an aperture 74 that extends therethrough,
as most clearly illustrated in Figure 5. A person of ordinary skill in the art
will
appreciate that the outrigger 72 may be formed with several apertures 74 that
permit
the outrigger 72 to be extended several discrete distances from the horizontal
support member 22.
Proximate to the end 32 of the horizontal support member 22
opposite the vertical support member 20, the horizontal support member 22
includes an aperture 76 extending therethrough, as most clearly illustrated in
Figure 1. The horizontal support member aperture 76 is oriented so that
sliding of
the outrigger 72 with respect to the horizontal support niember 22 allows one
of the
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outrigger apertures 74 to be aligned with the horizontal support aperture 76.
Alignment of one of the outrigger apertures 74 with the horizontal support
aperture
76 enables a pin 75 to be extended therethrough to thereby retain the
outrigger 72
in a fixed relation with respect to the horizontal support member 22.
Similar to the horizontal support member 22, the outrigger 72
preferably includes a mounting bracket 80 attached to the outrigger 72
proximate
to an end 82 of the outrigger that is opposite the horizontal support member
22.
The mounting bracket 80 is adapted to receive coupling pin 65 which in tum
receives a railing 70.
The railing 70 used in conjunction with the scaffold system 10 of
the present invention preferably includes three rail pockets 89, as most
clearly
illustrated in Figures 2 and 8. Depending on the spacing between individual
scaffold system units 10, it may be desirable to form the railing with arms
made of
standard wood 2 x 4 into.rail pockets 89. Similarly, depending on the height
of the
cross member 86, it may be desirable to include additional cross members (not
shown) at intermediate locations on the side arms 84.
The scaffold system 10 of the present invention also includes a
height extension adapter 100, as most clearly illustrated in Figures 6 and 7.
The
height extension adapter 100 includes a front side arm 102, a back side arm
104,
and a cross member ] 06 that extends between the front and back side arms 102,
104. The front and back side arms 102,104 are selected with a profile that
permits
the front and back side arms 102, 104 to engage coupling pins 65 resting in
mounting brackets 60. The front and back side arms 102, 104 preferably extend
above the cross member 106 to a height that is approximately level with a top
surface of wood planks 110 placed on the cross member 106. The back side arm
104 includes an aperture 112 that is adapted to receive coupling pin 65 on the
railing 70.
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Figure 7 also illustrates that the height extension adapter 100 may
be used in conjunction with the outrigger 72 by using mounting brackets 60 and
80
in combination with coupling pins 65.
An advantage of the present invention is that the scaffold system
can be erected from inside of the building. In particular, when using the
embodiment illustrated in Figure 2, the scaffold system 10 may be rotated and
then
passed between adjacent studs 16 to assemble the scaffold system 10. Once the
cross brace 36 is past the outer surface of the studs 16, the scaffold system
10 is
rotated until the vertical support member 20 is in a substantially vertical
orienta.tion.
The attaching bracket 40 is then placed so that the nail plate 52 is adjacent
to the
sill plate 14 of the wall 12. The scaffold system 10 is then pivoted until the
cross brace
36 rests against an outer surface of the wall 12. The scaffold system 10 is
then
anchored in place by driving nails through the nail plate 52 and into the sill
plate
14.
The process is repeated to place other scaffold system units 10 along
the wall 12. For most applications, the scaffold system units 10 are spaced
approximately 10 to 12 feet apart from each other. Once all of the scaffold
system
units 10 are in place, planks 110 (see Fig. 4) are placed on top of the
horizontal support member
22 or cross bar 106 to thereby provide a surface that may be walked on when
performing work on the wall or above the wall. A person of ordinary skill in
the
art will appreciate that the type and number of planks I 10 used with the
scaffold
system depends on the spacing between ttie scaffold system units as well as
the
intended loads that are to be placed upon the scaffold system 10.
Another embodiment of the present invention is designed for use
with an alterrrnative support structure. In particular, the scaffold system l
11 is
adapted to be mounted to a pole (not shown) that preferably has a
substantially
square profile, as most clearly illustrated in Figure 10. One type of pole
that is
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particularly suitable for use with this embodiment has sides that are each
approximately 4 inches long.
In this embodiment, the vertical support member 120, the horizontal
support member 122, the angle brace 124, and the cross brace 136 are
preferably
substantially the same as in the embodiment illustrated in Figure 1. The
attaching
bracket 140 includes an upper portion 130 and a lower portion 132, as most
clearly
illustrated in Figure 11. The upper portion 130 has an extension arm 142 and a
bracket 152.
Similar to the extension 42 illustrated in Figure 1, the extension arm
142 preferably has a substantially square profile and includes at least one
aperture
148 formed therein for retaining the extension arm 142 in a fixed relation to
the
other portions of the scaffold system using a pin 149.
The bracket 152 has a first leg portion 154, a second leg portion
156, and a third leg portion 158 that are configured in a substantially U-
shape. A
1'5 distance between the first portion 154 and the third portion 158 is
approximately
the same as the length of a side of the pole to which the bracket 152 is to be
attached. To facilitate attaching the bracket 152 to the pole, the second
portion 156
has at least one aperture 160 formed therein. The aperture 160 is adapted to
receive
a mounting device (not shown), such as a screw or a nail.
The lower portion 132 has a bracket 170 and a pair of arms 172
extending therefrom, as most clearly illustrated in Figures 12 and 13. The
bracket
170 has a first leg portion 174, a second leg portion 176, and a third leg
portion 178
that are configured in a substantially U-shape. A distance between the first
portion
174 and the third portion 178 is approximately the same as the length of a
side of
the pole (not shown) to which the bracket 170 is to be attached. To facilitate
attaching the bracket 170 to the pole (not shown), the second portion 176 has
at
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least one aperture 180 formed therein. The aperture 180 is adapted to receive
a
mounting device (not shown), such as a screw or a nail.
One of the arms 172 is attached to the first leg portion 174 and the
second leg portion 176. Each arm 172 preferably includes a horizontal portion
181
and a vertical portion 182 that extends from the horizontal portion 181, as
most
clearly illustrated in Figure 12. The horizontal portion 181 of each arm
preferably
includes an outward bend, as most clearly illustrated in Figure 12.
The lower portion 132 is preferably attached to the cross brace 136
with a pair of sleeves 184, as most clearly illustrated in Figure 10. The
sleeves 184
are each adapted to receive one of the vertical portions 182. A distance
between the
second portion 176 and the cross brace 136 is preferably approximately the
same
as the length of a side on the pole (not shown).
Yet another embodiment of the present invention is designed for use
with an alternative support structure. In particular, the scaffold system 210
is
mounted to a ladder 212, as most clearly illustrated in Figure 14. In this
embodiment, the vertical support member 220, the horizontal support member
222,
and the angle brace 224 are preferably substantially the same as in the
embodiment
illustrated in Figure 1. The attaching bracket 240 includes an upper portion
230 and
a lower portion 232. The upper portion 230 is preferably substantially the
same as
the attaching bracket illustrated in Figure 1. The upper portion 230 engages
an
upper rung 214 on the ladder 212.
The lower portion 232 engages a lower rung 216 on ladder 212 and
thereby prevents the scaffold system 210 from rotating with respect to the
ladder
212. A person of ordinary skill in the art will appreciate that it is possible
to have
one or more additional rungs 218 on the ladder 212 between the upper rung 214
and
the lower rung 216.
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While only one lower portion 232 is illustrated in Figure 14, the
scaffold system 2; 0 preferably includes two lower portions 232 so that one of
the
lower portions 232 engages each end of the lower rung 216. However, a person
of
ordinary skill in the art will appreciate that it is also possible to use
alternate
structures for attaching the lower end of the scaffold system 210 to the
ladder 212.
The lower portion 232 preferably includes a main portion 240 with
a first side 242 and a second side 244, as most clearly illustrated in Figure
15. The
main portion 240 also preferably includes a first end 246 and a second end
248.
The lower portion 232 preferably includes a sleeve 250 that extends from the
first
side 242 proximate the first end 246. The sleeve 250 preferably has a
substantially
square profile with an inner diameter that is approximately the same as the
outer
diameter of the cross brace 236 so that the sleeve 250 is slidable over the
cross
brace 236. A fastening device 252, such as a screw, extends through the sleeve
250
and engages the cross brace 236 to retain the lower portion 232 in a desired
position
with respect to the cross brace 236.
The lower portion 232 also includes a projection 254 extending
from the second side 244 proximate the second end 248. The projection 254
engages the lower rung 216 and thereby prevents the scaffold system 210 from
pivoting with respect to the ladder 212.
To enhance the stability of the scaffold system 210 when placed
against a wall (not shown), the scaffold system 210 includes a stabilizing bar
260,
as mosi clearly iliustrated in Figure 14. Tli-e stabilizing bar 260 has a top
leg 263
and a center leg 262 that are generally in a T-shape, as most clearly
illustrated in
Figure 16. The center leg 262 of the stabilizing bar 260 is preferably
removably
attached to the horizontal bar 222 using a pin 264.
Another aspect relates to attaching planks 110 to the scaffold system
10 to prevent the planks 1 10 from moving with respect to the scaffold system
10.
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The planks I 10 are preferably attached to the scaffold system 10 using at
least
mounting bracket 190, as most clearly illustrated in Figure 17.
The mounting brackets 190 include a first leg portion 192, a second
leg portion 194, and a third leg portion 196 that are in J-shape. A distance
between
the first leg portion 192 and the third leg portion 196 is preferably
approximately
the same as the thickness of the plank 110. The third leg portion 196 is
preferably
outwardly flared to enhance the ability to engage the plank I 10 in the
mounting
bracket 190. The third leg portion 196 also preferably includes at least one
aperture
198 formed therein for preventing the plank I 10 from moving with respect to
the
mounting bracket 190.
Although the present invention has been described with reference
to preferred embodiments, workers skilled in the art will recognize that
changes
may be made in forni and detail without departing from the spirit and scope of
the
invention.
