Note: Descriptions are shown in the official language in which they were submitted.
CA 02436676 2003-08-07
BALUSTER RETAINING MEIUIBER
Background of the Invention
i) Field of the Invention:
This invention relates to a retaining member for connecting balusters to rails
of a railing
system and more particularly relates to a system which permits vertical
orientation of
balusters into rails having openings perpendicular to the longitudinal axis of
the rails,
where the rails are oriented at an angle from the horizontal when adjacent a
stairway.
ii) Related Art
Railing systems which are made up of upper and lower rails with balusters
interposed
between the rails are well known in the art. As well, a railing system in
which the
balusters are inserted into openings in a surface of each rail are well known.
In those
systems, the upper and lower rails are rigidly connected to posts on each end
with the
balusters interposed between the rails fitted within openings in the Lower
surface of the
upper rail and the upper surface of the lower rail to hold the balusters in
place. The
balusters are manually oriented in a vertical direction, irrespective of the
angle at which
the rails are oriented. Because rails positioned adjacent a stairway or set of
stairs must
be angled downwardly at an angle corresponding to the angle of the stairway
(that is the
angle corresponding to the "run" and "rise" of the stairway), difficulties can
arise in
CA 02436676 2003-08-07
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providing a method for orienting the balusters vertically when interposed
between rails
which are angled from the horizontal.
In the past, one method of manufacturing rails for this type of railing system
was to
orient the openings in each rail into which an end of a baluster is inserted
at an angle in
relation to the longitudinal axis of the rail sufficient to result in a
vertical baluster
orientation when the rails are angled in use adjacent a stairway. This has
meant that
special tooling equipment, or time consuming adjustment of existing equipment
had to
be undertaken to drill these openings at the appropriate angle. Furthermore,
some
railing systems are sold, without any pre-drilled openings, to consumers and
contractors
who install these systems. Consumers or contractors are then required to drill
openings
of appropriate size and orientation in order t~ accept the balusters between
the rails
when the railing system is assembled. It is much easier for those consumers or
contractors to drill openings in the rails which are perpendicular to the
longitudinal axis
of those rails, as compared to attempting to drill a plurality of openings at
the same
angle, corresponding to the rise angle of the stairway, to provide a
consistent vertical
orientation of a plurality of balusters between the rails whE;n those rails
are positioned
adjacent a stairway at an angle from the horizontal. This difficulty is
compounded by
the need to ensure that openings in the top rail align with openings in the
bottom rail.
As well, the ability to use rails which have an opening perpendicular to the
longitudinal
axis of the rail permits consumers and contractors to use the same rails for
use in a
railing system adjacent a set of stairs as are used in a railing system
adjacent a
horizontal surface. In addition, the rails may be oriented with a particular
end either at
CA 02436676 2003-08-07
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the high end of the stairway, or the low end of the stairway, whereas rails
having angled
openings are required to be oriented in one direction to properly align the
openings so
that the balusters are oriented vertically.
As a consequence, there is a need for a railing system which permits the use
of rails
having openings to accept balusters between the rails which are formed into
the rails in
a direction perpendicular to the longitudinal axis of the rails and which
enables vertical
orientation of the balusters interposed between the rails when the rails are
oriented at
an angle from the horizontal such as when the rails are used adjacent a
stairway.
The railing system of one embodiment of the subject invention requires that
the
balusters used with rails positioned adjacent a stairway or set oi~ stairs be
cut at each
end to properly fit retaining members, as best depicted in figure 2A. This
requires
further processing of balusters by the baluster manufacturer or kyy the user
in order to
properly fit balusters with inserts and rails when used adjacent the stairway
or set of
stairs. in most cases the manufacturer will not know how many balusters are
required
'to be cut for use in a railing system adjacent a stairway as compared to the
number
needed in a railing system along a flat section, that is, not positioned
adjacent a
stairway. Similarly, users may not know the exact number of balusters which
will be
positioned adjacent a stairway at the time they purchase a railing system.
As a consequence, there is a need for a railing system in which balusters
having ends
perpendicular to the longitudinal axis of the baluster may be employed both in
straight
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railing sections and angled sections positioned adjacent a stair way. This
eliminates the
need to cut baluster ends at an angle either when initially manufactured or by
the
installer for use adjacent a stairway. Further when only one type of baluster
is required
for use in the entire railing system neither the manufacturer nor the
installer need be
concerned about the number of balusters needed adjacent staiirways and the
number
along a flat section in order to obtain the appropriate number of balusters
for each type
of application.
In addition, the railing system of the embodiment depicted in fige.are 1A
results in direct
contact between the wood rails and the aluminium balusters when the balusters
are
inserted into the holes in the rails. in most cases, the wood used for outdoor
railing
systems has been pressure treated with a preservative, a sually either
chromated
copper arsenate (CCA) or alkaline copper quaternary (AC(~). Both preservatives
contained copper which can react adversely with aluminum to corrode the
aluminum.
As aluminum is a preferred metal for manufacturing balusters in the present
invention,
there is a need for an alternate embodiment railing system utilizing inserts
between the
baluster and the rails which also separates the baluster from the rails to
prevent copper
induced corrosion of the aluminum balusters.
Summary of the Invention
in one embodiment the invention provides a railing system for a stairway which
includes
a pair of rails, each having a plurality of openings extending lateraily into
one side of the
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rails in a direction perpendicular to the longitudinal axis of the rails. A
plurality of
balusters are provided for extending between the rails and a plurality of
retaining
members are provided for con~~ecting an end of a baluster to one of the
openings. The
retaining members include a rail section dimensioned to fit within the opening
and a
5 baluster section dimensioned to be secured to an end of the baluster. The
rail and
baluster sections are oriented with respect to one another at a predetermined
angle so
that when the balusters are connected to the rails by the members and the
rails are
positioned for use adjacent a stairway at an angle from the horizontal, the
balusters are
oriented vertically.
In a further embodiment, the rail section is of an outer diameter and the
opening is of a
corresponding diameter to provide a friction fit of the rail section within
the opening.
In a further embodiment, the baluster includes a baluster opening at one end
dimensioned to accept the baluster and of the retaining member into the
baluster
opening.
In a further embodiment, the baluster section is of an outer diameter and the
baluster
opening is of a corresponding diameter to provide a friction fit of 'the
baluster section
within the opening.
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In a further embodiment, the rail section is connected to the opening by a
tighter fit
resulting in a higher level of friction fit as compared to the baluster
section and the
baluster opening.
In a further embodiment, the predetermined angle is between 30 degrees and 36
degrees.
In a further embodiment, the predetermined angle is about 32.5 degrees.
In a further embodiment, the baluster section is contoured with a frusto-
conical outer
periphery with the larger diameter at the end adjacent the rail section.
In a further embodiment, the rail section includes a plurality of ribs
defining the outer
periphery of the rail section.
9n a further embodiment, the baluster section comprises a plurality of ribs
defining the
outer periphery of the baluster section.
In a further embodiment, the baluster section is of a lesser diameter than the
rail section
and a lip is formed at the region where the rail and the baluster sections
meet.
In a further embodiment, the lip defines a lip plane that is perpendicular
with the outer
periphery of the rail section.
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1n a further embodiment, the lip acts as a contact region contacting the end
of the
baluster when the baluster is attached to the baluster section, the lip
preventing further
insertion of the baluster section into the baluster.
1n a further embodiment, the rail section is dimensioned in length equal to
the depth of
the opening so that when the rail section is in the opening contacting the end
of the
opening, the lip plane is coplanar with a plane defined by the side of the
rail into which
the opening extends so that when the baluster is attached to the baluster
section to
cover the entire baluster section, the lip acts as a contact region contacting
the end of
the baluster.
In a further embodiment, the ends of the baluster are paralfe6 with one
another and form
a plane which is at a baluster-end angle with respect to the longitudinal axis
of he
baluster.
In a further embodiment, the baluster end angle is the same as the
predetermined
angle.
In another embodiment of the invention the retaining member includes a buffer
section
interposed between the first end and second end and dimensioned to contact the
baluster secured to the first end preventing the baluster from moving past the
first end in
a direction toward the second en,l.
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In a further embodiment the buffer section includes a flange to contact the
baluster to
prevent the baluster from moving past the first end in a direction toward the
second end.
The buffer section may include a cylindrical section having a wedge shaped
cross-
section, a first face adjacent the first end and a second face adjacent the
second end
with the diameter of the cylindrical section being greater than the diameter
of the first
end to contact a baluster secured to the first end to prevent the baluster
from moving
past the first end in a direction toward the second end.
A plane defined by the first face may be positioned with respect to a plane
defined by
the second face at an angle equal to the predetermined angle, or at an angle
between
30 degrees and 36 degrees or an angle of 32.5 degrees.
In a further embodiment at least a portion of the diameter of the cylindrical
section is
greater than the diameter of an opening in a rail to which the baluster is to
be attached
to prevent the retaining member from moving into the opening past the second
end.
The second end may include a plurality of barbs at an outer periphery of the
second end
to assist in securing the second end into a opening in a rail to which the
baluster is to be
attached.
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l'he first end may include a plurality of barbs at an outer periphery of the
first end to
assist in securing a baluster to the first end.
Drawings
~y way of example, specific embodiments of the invention will now be
described, with
reference to the accompanying drawings, in which:
FIGURE 1 is a perspective view of a rail system of the present invention,
adjacent a
stairway;
FIGURE 1A is a close-up view of a section of FIGURE 1 showing a retaining
member of
the present invention connecting a lower end of a baluster to an opening in
the lower rail
of the railing system;
FIGURE 2 is a perspective view of the railing system of FIGURE 1;
FIGURE 2A is a close-up view of a section of FIGURE 2 in an exploded view
showing a
baluster interposed between upper and lower rails with baluster- retaining
members
interposed between each end of the baluster and each rail;
FIGURE 3 is a perspective view of a baluster retaining member of the present
invention;
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FIGURE 4 is a side view of the baluster retaining member of FIGURE 3;
FIGURE 5 is a front view of the baluster retaining member of FIGURE 3; and
5 FIGURE 6 is a rear view of the baluster retaining member of FIGURE 3.
FIGURE 7 is a front perspective view of a baluster retaining member of an
alternate
embodiment of the present invention;
10 FIGURE 8 is a rear perspective view of the baluster retaining member of
FIGURE 7;
FIGURE 9 is a side view of the baluster retaining member of FIGURE 7 shown
connecting a lower end of a baluster to a lower rail;
FIGURE 10 is a front view of the baluster retaining member of FIGURE 7;
FIGURE 11 is a cross-sectional view of the baluster retaining member of FIGURE
7;
FIGURE 12 is a sectional view of the segment denoted as FIG. 12 in FIGURE 11.
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11
Detailed Description of the Preferred Embodiments)
Referring initially to Figures 1 and 1A, railing system 10 is shown adjacent
stairway or
set of stairs 12. Railing system 10 includes balusters 14 interposed between
upper rail
16 and lower rail 18.
Stairway 12 includes a pair of parallel-spaced opposed stringers 20 and 22
attached at
an upper end to beam 24. Lower ends of stringers 20 and 22 rest on a support
surface
(not shown). A plurality of tread members 26 are positioned horizontally on
corresponding plurality of vertical support sections 27 of stringers 20 and
22.
A typical stairway 12 has a 7 inch rise 30 and a 11'/4 inch run 32 which is
equivalent to a
rise angle 28 from a horizontal support surface of about 3.2.5 degrees.
Railing system 10 includes upper post 34 and lower post 36. Upper post 34 is
secured
to a top face 38 of beam 24 and lower post 36 is attached to, or rests on, the
support
surface and is attached to a lower region of stringer 22. Lower post 36 may
further be
attached to the lowermost tread member 26 at notch 40. Upper and lower rails
16 and
18 are positioned between the posts 34 and 36 and extend downwardly from upper
post
34 to lower post 36 at an angle of about 32.5 degrees from the horizontal so
as to
correspond with rise angle 28 of stairway 12. Upper and lower rails 16 and 18
have
parallel ends which are cut at an angle of about 32.5 degrees from that
perpendicular to
the longitudinal axis of rails 16 and 18 which also corresponds to the rise
angle 28.
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VUhen railing system 10 is assembled adjacent stairway 12, rails 16 and 18 are
attached
to a side of posts 34 and 36 so that the ends of rails 16 and 18 lie flush
with adjacent
sides of posts 34 and 36. This ensures that the angle of rails 16 and 18 from
the
horizontal, that is angles 80 and 82 shown in Figure 2A, correspond to rise
angle 28
ensuring that rails 16 and 18 are positioned generally at are angle from the
horizontal
corresponding to rise angle 28 of stairway 12.
A plurality of balusters 14 are interposed between rails 16 and 18 and are
rigidly
secured between those rails in a vertical orientation, while rails ~ 6 and 18
are oriented
at an angle from the horizontal as discussed above. Referring to Figures 1A
and 2A, in
order to provide for a vertical orientation of balusters 14 in conjunction
with rails 16 and
18 which are angled from the horizontal by angles 82 and 80, retaining members
42 are
employed to attach balusters 14 to rails 16 and 18. Upper face 44 of rail 18
includes a
plurality of openings 46 extending laterally into face 44, representing a side
of rail 18, in
a direction perpendicular to face 44 also perpendicular to the longitudinal
axis of rail 18.
Retaining member 42 fits within opening 46 and includes rail section 64 which
is
dimensioned in width with respect to the width of opening 46 to provide a
friction fit
engagement within opening 46. Baluster 14 includes opening 48 in an end of
baluster
14 into which baluster section 62 of retaining member 42 may be inserted.
Baluster
section 62 of retaining member 42 is dimensioned in width with respect to
opening 48 to
provide a friction fit engageme~lt with opening 48 into which baluster section
62
retaining member 42 is inserted. This is best seen in Figure 2A.
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As best depicted in Figures 2 and 2A, upper rail 16 includes a lower face 50
into which
a plurality of openings 52 are formed. Openings 52 extend laterally into face
50 and
thereby into one side of rail 16. Openings 52 are of the same diameter and
length as
openings 46. Openings 52 extend in a direction perpendicular to face 50 and
perpendicular to the longitudinal axis of rail 16. Rail section 64 of
retaining member 42
and opening 52 are dimensioned to provide a friction fit engagement of rail
section 64
within opening 52. Baluster 14 includes an opening (not shown) at its upper
end 54,
similar to opening 48 in lower end 56 of baluster 14 as described above.
Baluster
section 62 of retaining member 42 and the opening in end 54 are dimensioned
fio
provide a secure friction fit engagement of baluster section 62 of member 42
within the
opening at end 54.
Ends 54 and 56 are cut at an angle from the longitudinal axis equal to rise
angle 28 of
about 32.5 degrees and are parallel with one another. This ensures that upper
face 58
and lower face 60 are coplanar with faces 50 and 44, respectively. Lower face
60 is
shown in its assembled position coplanar with face 44 in Figure 1A.
Referring to Figures 3, 4, 5, and 6, retaining member 42 is depicted in
perspective, side,
front and rear views. Retaining member 42 includes baluster section 62
integrally
joined to rail section 64. Baluster section 62 includes four ribs 56 oriented
at right
angles to one another and extending the length of baluster section 62. Ribs 66
are
integrally joined with four ribs 68 oriented at right angles with respect to
one another of
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rail section 64. Ribs 68 of rail section 64 are wider than ribs 66 providing a
larger
diameter 70 as compared to diameter 72 of baluster section 62 (best seen in
Figure 4).
UVhile not shown, ribs 66 may be tapered with a larger diameter adjacent ribs
68 to
provide a general frusto-conical outer periphery to facilitate insertion of
baluster section
62 into baluster 14.
As best seen in Figure 4, rail section and baluster section .are angled with
respect to
one another at angle 74 which is equivalent to rise angle 28 of ataout 32.5
degrees.
~lllhen rails 16 and 18 are oriented at an angle from the horizontal at angles
82 and 80,
respectively, of about 32.5 degrees, rail section 64 may be inserted into
opening 46 or
opening 52 with baluster section 62 oriented in a vertical direction (see
Figure 1A). As
depicted in Figure 2A, retaining member 42 is inserted into opening 52 so that
baluster
section 62 faces vertically as is baluster section 62 of retaining member 42
positioned
within opening 46 of rail 18. This properly orients baluster 14 in a vertical
position as
depicted in Figures 1 and 2 when attached to both baluster sections 62 of
retaining
members 42.
Rail section 64 is dimensioned at diameter 70 which is generally equivalent to
diameter
of openings 46 and 52 to provide a friction fit of rail section 64 within
either one of
openings 46 or 52. As well, the length 76 of rail section 64 is equal to the
depth of
openings 46 and 52. As best seen in Figures 3 and 4, because ribs 68 are of
larger
diameter 70 as compared to diameter 72 of ribs 66, lip 78 is formed at the
inner end of
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ribs 68 where ribs 68 merge with ribs 66. Lips 78 on ribs 68 are in coplanar
alignment
with each other as ribs 68 are all of equal length 76.
Length 76 is equal to the depth of openings 46 and 52 and when rail section 64
is
5 positioned within opening 46 or opening 52 with rail section 64 contacting
the end of
opening 46 or opening 52, lips 78 are in coplanar alignment with the plane of
corresponding face 44 or 50. As a consequence, when baluster section 62 is
positioned
within one of opening 48 or opening in end 54 of baluster 14, lips 48 act as a
stop
contacting corresponding face 58 or 60 which rests against lip 78, as best
depicted in
10 Figure 1A. This provides additional support to balusters 14 which contacts
lips 78,
rather than faces 44 or 50 which are generally made of wood or other soft
material,
softer than material used to construct retaining members 42.
As well, because retaining members 24 have rail section 64 which is positioned
at angle
15 74 with respect to baluster section 62, equivalent to angles 80 and 82 of
rails 18 and 16,
balusters 14 are oriented in a vertical position.
The foregoing description of a preferred embodiment has been directed to the
most
popular rise and run angle of a stairway, namely a 7 inch rise and an 11 %4
inch run,
resulting in about a 32.5 degree angle from the horizontal. However, other
stair angles
may also be accommodated and will similarly provide a 'vertical baluster
interposed
between rails angled from the horizontal by changing the predetermined angle
of the
retaining member 42. For example, other popular stair runlrise ratios are: (i)
a rise of 6
CA 02436676 2003-08-07
16
112 inches and run of 11 inches, resulting in a rise angle of about 30
degrees; (ii) a rise
of 7'h inches and run of 10 inches resulting in a rise angle of about 36
degrees; and a
rise of 7'/e inches and a run of 10'/4 inches resulting in a rise angle of
about 35
degrees. By providing a predetermined angle 74 and positioning rails 16 and 18
at
angles 82 and 80 equivalent to 30 degrees a rise of 6 112 inches and a run of
11 inches
can be accommodated. Similarly, a rise of 7'/2 inches and a run of 10 inches
can be
accommodated by providing angles 74, 82 and 80 of 36 degrees and a rise of 7
%4 and
run of 10'/4 accommodated by providing angles 74, 82 and 80 of 35 degrees.
An alternate embodiment of the invention will now be discussed with reference
to
Figures 7-12. This embodiment provides an alternate retaining member 142 which
incorporates buffer section 190 which is angled thereby obviating the need to
cut upper
end 54 and lower end 56 of baluster 14 at an angle different frorn that
perpendicular to
the longitudinal axis of baluster 14.
Retaining member 142 also separates baluster 14 from rails 16 and 18 to
prevent
copper induced corrosion of baluster 14 caused by the copper in the
preservative
commonly found in rails 16 and 18. As depicted in figure 1A, use of retaining
member
42 of the first embodiment discussed above causes contact between lower face
60 of
baluster 14 and upper face 44 of lower rail 18~ Although not shown, similar
contact will
occur between upper face 58 of baluster 14 and lower face 50 of upper rail 16.
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Referring to Figures 7 and 8, retaining member 142 is a perspective view with
Figures 7
viewed facing baluster section 162 and Figure 8 viewed facing rail section
164. Buffer
section 190 is positioned between sections 162 and 164 arid joins sections 162
and 164
together.
Buffer section 190 has a cylindrical outer periphery with a wedge shaped cross-
section.
Baluster section end face 192, sometimes referred to as a first face, forms a
first end
attached to baluster section 162, seen best in Figures 7 and 10. Rail section
end face
194, sometimes referred to as a second face, forms a second end attached to
rail
section 164, seen best in Figure 8.
Referring to Figure 9, a plane defined by face 192 is oriented with respect to
a plane
defined by face 194 at angle 196, equal to a predetermined angle which will
orient
baluster 14 vertically when attached to lower rail 18 when rail 18 is
positioned adjacent
a stairway or set of stairs 12. The predetermined angle may be iaetween 30
degrees
and 36 degrees and preferably is about 32.5 degrees when use adjacent a
stairway 12
having a 7 inch rise 30 and 11 1/4 inch run 32 (Figure 1 ).
Retaining member 142 includes rail section 164 which is dimensioned in width
with
respect to the width of opening 52 to provide a friction fit engagement with
opening 52.
Retaining member 142 also includes baluster section 162 which is dimensioned
in width
to provide a friction fit engagement with opening 48 of baluster 14.
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18
Face 192 is planar and is dimensioned to contact baluster 14 when baluster
section 162
is inserted in opening 48 as depicted in Figure 9. Face 192 prevents baluster
14 from
moving past baluster section 162 in the direction of rail section 154.
Referring to Figure
8, face 194 has a diameter larger than the diameter of opening 52 to contact
upper face
44 of lower rail 18 when rail section 164 is inserted into opening 52 to
prevent retaining
member 142 from entering opening 52 past rail section 164.
It should further be noted that, as depicted in Figure 9, the bottom end of
baluster 14 is
cut perpendicular to the longitudinal axis of baluster 14 due to the
interposing of buffer
section 190 between baluster section 162 and rail section 164 and the
positioning of
faces 192 and 194 with respect to each other at angle 196. As well, buffer
section 190
separates the bottom end of baluster 14 from upper face 4.4 of lower rail 18
preventing
contact between baluster 14 and rail 18 to reduce the effect of any copper
induced
corrosion on baluster 14.
Referring to Figures 11 and 12, ~~retaining member 142 is shown in a cross-
section view.
In order to improve the securing of baluster section 162 into opening 48 a
plurality of
barbs 198 are provided at the outer edge of each cross member 200 (Figure 7).
Barb
198 is shown in close up in Figure 12 and comprises elongated sloped section
202
connected to lateral section 204. Lateral section 204 is positioned closer to
buffer
section 190 as compared to sloped section 202. As best seen in Figure 9, this
provides
additional means of securing baluster 14 in opening 48 as barbs 198 contact
the inside
CA 02436676 2003-08-07
19
of opening 48 to provide a plurality of finger-like extensions which secure
baluster
section 162 inside opening 48.
Similarly, rail section 164 comprises a plurality of barbs 206 on the outer
periphery of
cross members 208 (Figure 8). as seen in Figures 9 and '11, barbs 206 are
positioned
opposite in direction as compared to barbs 198. This orientation of barbs 206
facilitates
the securing of rail member 164 inside opening 52 of lower rail 18.
ps depicted in Figure 12, each crass member 200 of baluster section 162 also
includes
angled section 210 (also depicted in Figure 11 ), which provides a top region
of smaller
diameter as compared to the diameter of the rest of baluster section 162 at
cross
members 200. This facilitates insertion of baluster section 162 into opening
48 of
baluster 14.
Having thus described preferred embodiments of a railing system for a stairway
and a
baluster retaining member, it wilbe apparent by those skilled in the art how
certain
advantages of the present invention have been achieved. It should also be
appreciated
that various modifications, adaptations, and alternative embodiments thereof
may be
made within the scope and spirit of the present invention. For example, while
specific
angles associated with certain run/rise ratios have been described, it should
be
apparent that the inventive concepts described above would be equally
applicable to
any number of different rise/run ratios by making appropriate adjustment to
angles 74,
82 and 80, consistent with rise angle 28. Moreover, the words used in this
specification
CA 02436676 2003-08-07
to describe the invention and its various embodiments are to be understood not
only in
the sense of their commonly defined meanings, but to include by special
definition in
this specification structure, material or acts beyond the scope of the
commonly defined
meanings. Thus, if an element can be understood in the context of this
specification as
5 including more than one meaning, then its use in a claim must be understood
as being
generic to all possible meanings supported by the specification and by the
word itself.
The definitions of the words or elements of the following claims are,
therefore, defined in
this specification to include not only the combination of elements which are
literally set
forth, but all equivalent structure, material or acts for performing
substantially the same
10 function in substantially the same way to obtain substantially the same
result. The
described embodiments are to be considered illustrative rather than
restrictive. The
invention is further defined by the following claims.
