Note: Descriptions are shown in the official language in which they were submitted.
CA 02246502 1998-09-04
Title: Post and rail system using extrudable plastic posts.
Background of the Invention.
l.Field of the Invention
The present invention relates to a post and rail system
_5 which may be used as a railing system for decks, or may be used
as fencing. The system makes use of extrudable plastic posts
and rails, and provides improved means for supporting the posts
and for connecting the rails to the post.
2.Prior Art
_10 Hollow posts, often made of plastic materials, are known
for use in deck railing systems, and for fences . In the decking
field, commonly the posts have been connected directly at their
sides or bases to wooden parts of the decking, for example by
bolts, but such connection means lack firmness and strength.
_15 In some cases, both for rails and fencing, hollow posts
have been supported by a rigid support member having a lower
portion securely held by a ground fixture or part of the
decking, and having an upper portion extending within the post .
The following patents show examples of such constructions:
20 U.S.Pat.No.3,910,561, which issued Oct.7,1975 to Fornells;
U.S.Pat.No.4,702,459, which issued Oct.27,1987 to
Moschner;
U.S.Pat.No.4,461,461, which issued Ju1.24,1984 to Caron;
U.S.Pat.No.4,892,292, which issued Jan.9,1990 to Russell;
25 U.S.Pat.No.4,958,807, which issued Sep.25,1990 to Wylie;
and
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CA 02246502 1998-09-04
U.S.Pat.No.5,617,697, which issued Apr.8,1997 to Erwin.
The Erwin patent shows a hollow plastic deck post
supported by an internal metal tube . The tube contacts only one
side of the post, and therefore could allow some distortion of
the post if it were to be subjected to stress. It also requires
a bolt to be inserted through one side of the post.
The patents to Caron and Russell are similar to each
other, and both show hollow circular posts supported by steel
pipes or bars fixed to a base, the posts being joined to the
pipes or bars by spacers in the form of plain tubular members.
The rails are attached to the posts by fittings which resemble
right angled pipe fittings. The Moschner patent also shows
hollow plastic posts supported by a rod or pipe, but here the
means connecting the rod or pipe to the post are integrally
formed with the post, and are combined with formations for
holding the rails. This means that the post is not of constant,
extrudable cross-section, and must be of more expensive molded
construction.
The patent to Fornells shows a plastic fence construction
with a relatively complex arrangement for attaching the rails
to the posts, which allows the angle of inclination of the
rails to be varied.
The Wylie patent shows an aluminum extruded post of
complex construction, having an integral spacer surrounding an
inner support tube.
Apart from Erwin, all of this prior art shows
constructions which are somewhat complex and expensive,
especially in relation to the connections between posts and
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CA 02246502 1998-09-04
rails. The present invention provides a construction in which
cost is minimised, firstly by having major parts of the railing
or fencing system formed of extrudable parts, usually of
plastic, and secondly by having a connection between the posts
and rails which does not require any special components.
Furthermore, the hollow posts are more fully supported than for
example in the Erwin patent.
Summary of the Invention
In the present invention, hollow extruded plastic posts
are used which have an internal cavity of constant cross-
section; usually the posts are square. The rails, which are
narrower in plan view than the posts, are connected to the
posts simply by routing apertures in the side walls of the
posts. The routing may be done by an installer, in accordance
with site or customer requirements.
The nature of the joints between connecting posts and
rails necessitates that, to prevent dislocation of the joints,
there be sufficient overlap between the outer sides of the
posts and the inner ends of the rails. If, for example, the
post and spacer arrangements used by Caron or Russell were to
be used with simple apertures in the post walls to receive ends
of the rails, the rails would not project sufficiently far into
the posts to be secure.
Accordingly, the present invention provides support means
for a hollow post having a side wall defining a cavity of
constant cross-section, the post being of the type used to
support horizontal rails, comprising:
a rigid support member, such as a steel tube, having upper
and lower end portions, the lower end portion adapted to be
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CA 02246502 2002-03-15
fixed in vertical position while the upper end portion extends
within the hollow post, and
at least one :pacer with an inner bore sized to snugly
receive the rigid si.zpport member, and having external surfaces
suitable for firm engagement within the cavity of the post and
configured and arranged to provide clear space within the side
walls at the location of the spacer, which space is suitable
for receiving substantial lengths of end portions of the rails
when inserted into apertures formed .in the side walls of the
post.
Preferably, thf= spacer has longitudinal protrusions which
are separated by side areas which are spaced within the side
walls at the locations of the rail ends. For this purpose the
spacer is preferably extruded, from plastic material or
aluminum, and has a 'tubular portion with an inner bore sized to
snugly receive the r~_gid support. member, and the protrusions
are in the form of longitudinal ribs projecting outwardly from
the tubular portion and suitable for. firm engagement within the
cavity of the post, the ribs providing a clear space between
2y the side wall of t:he post and the tubular portion of the
spacer. This allows the spacer to occupy substantially the full
length of the post while still allowing space for the rail ends
to project into the post. Where, as is preferred, the post is
square, such a spacer can provide a clear space adjacent the
2a interior of the post. side wall, with the minimum clear space
between the interior of the post side wall and the tubular
portion being at least: 1/2 inch, and preferably 5/8 of an inch.
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The spacer ribs may project in mutually perpendicular
planes, with each z°ib having an outer edge with at least one
side flange lying at an angle of between 45 and 90° to the
respective rib so that the flange is caused to bend by contact
with the inner surf<~ce of the post cavity, whereby the flanges
provide an interference fit between the spacer and the post.
For square posts, each rib preferably terminates in a pair of
the flanges which project from th~~ outer edge of the rib in
arrowhead formation,, the flanges being bent inwardly to provide
an interference fit within the corners of the post. A spacer of
this form is itself a novel component, and is usable with
presently available hollow square posts, and commonly available
round steel pipes as the support members.
A similar spacer' may be used :Eor posts of circular cross
section, but here the side flanges will project from the ribs
at an angle close to ~>0°, so as to be slightly bent when forced
into the circular p~:~st .
The tubular portion of the spacer may have internal
surface portions, such as projections, suitable for providing
an interference fit on the circular support tube. The tubular
portion preferably can receive a tube of 1 7/8 inches or 2
inches or more in diameter.
Brief Description of the drawing's.
Preferred embc>d.iments of the invention will now be
described by way of example with reference to the accompanying
drawings, in which;
Fig.l is a sectional elevation of a deck railing post
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incorporating one form of the invention, and showing end
portions of two rails;
Fig. la is a fragmentary view on line la-la of Fig. l;
Fig.2 is a cross-sectional plan view on lines 2-2 of
Fig. l;
Fig.3 is a view similar to Fig.l of an alternative
construction;
Fig.4 is a cross-sectional view on lines 4-4 of Fig.3;
Fig.5 is a sectional elevation of a fence post with
portions of railings attached;
Fig.5A is a fragmentary view of a variation of the fence
post arrangement of Fig.5; and
Fig.6 is a view similar to Fig.4 of a variation using a
circular post.
Detailed Description.
Fig.l shows a wooden deck 10 of standard construction
supported on vertical joists 12 of 2 inch by 10 inch timber. At
spaced intervals, the joists 12 at the outside of the deck have
fixed to them a lower portion of a tube or pipe 14, secured by
bolts 13 passing through drilled bores in the pipe and through
the adjacent joist. This pipe 14 is a 1 7/8 inch diameter
galvanized steel pipe readily available to builders, and has
suitable strength for supporting a railing post. The pipe 14
has an upper portion extending up through the deck, where it is
received in the center of a hollow post 15. In the construction
shown, the pipe 14 extends up the major part of the height of
the post, which will normally be about 2 1/2 or 3 feet above
the deck level.
The post 15 is of constant square cross-section, of about
4 inch width, and has its flat side walls joined by rounded
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corners. It is preferably formed by extrusion from plastic
material. The pipe 14 supports the post by the intermediary of
upper and lower spacers 16, the cross-sectional form of which
is shown in detail i.n Fig.2. As shown, each spacer includes an
inner, cylindrical, tubular portion 16a which snugly receives
the cylindrical pipe 14, and ribs 16b projecting radially
outwardly from the tubular portion in mutually perpendicular
planes. Each rib tEerminates in a pair of flanges 17 which are
oriented in arrowheaf. formation with respect to the ribs, and
which have outer surfaces which subtend between them an angle
of greater than 90°, in practice about 110 or 120°. The
individual flanges :I_7 lie at angles between 45 and 90° to the
respective rib. The arrangement of the ribs and flanges is such
as to make the spacer an interference fit into the post, with
the flanges flexing to take care of minor inconsistencies with
the internal measurements of different posts and always
ensuring a firm fit with no play. 'rhe spacers also have small
ribs 18 internally of the tubular portion to ensure an
interference fit on the pipe 14.
2~~ Although the spacers are an interference fit both with the
post and the pipe, preferably the upper spacer is fixed both to
the post and to the pipe 14 so that= the post cannot easily be
removed . For this purpose one or mor a screws 19 may be inserted
into bores drilled radially through. the post, the upper spacer
2!~ 16, and the pipe 14. Alternatively, first screws can be
inserted through they spacer and pipe before the post is
positioned, and second screws are later inserted through the
post and spacer.
The railing system also includes horizontal rails 20 of
3~) known form, of rectangular form and having a width of 3 3/8
inches and a height of 1 3/4 inches, and pickets 22 which are
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square sections of 1 1/2 inch width. Both the rails and the
pickets are hollow and are formed from plastic by extrusion.
The rails have their end portions 20a inserted into apertures
cut in the sides of posts by a router, in accordance with
customer requirement:. Conveniently, the spacers 16, which in
this embodiment would interfere with the end portions 20a of
the rails, are positioned just below the end portions. Also,
the rails 20 have their end portions 20a bevelled at one side,
as shown in Fig.2, where these are required to meet on a
corner. The pickets 22 are assembled by having their upper and
lower end portions in;~erted into suitable apertures in the tops
and bottoms of the rails. The spacers 16 provide a clear space
of over 3/4 inch, in fact about 7/8 inch, between the inner
surfaces of the post side walls and the outer surface of the
pipe 14. In proportional terms, the clear overlap space is more
than 20% of the post width.
Referring to Figs.3 and 4, these show a variation of the
invention in which t:he rails 120 are vertically elongated,
being 3 1/2 inches high and 1 1/2 inches wide, and are used
without pickets. Ira this construction the rail end portions
120a are centered on the sides of the posts and do not
interfere with the ribs of the spacer 116. This spacer has the
same cross-section <~s the spacer 16 previously described, but
it is longer and can extend past the inner end portions of the
2.5 rails. It has ribs 116b with end flanges 117, similar to
flanges 17. The rails 120 in this case are butted against the
sides of the tubular portion 116a, but this still allows a
clear space for the rail end portions 120a to overlap within
the post side wall, this space being more than 1/2 inch,
actually about 5/8 inch, so that a secure fitting is produced.
The relationship of the spacer 116 and the rail end portions
here means that the spacer can extend up the entire length of
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post which is above the deck 10, as shown in Fig.3.
Fig.5 shows the same basic combination of square plastic
extruded post, rectangular extruded rails, and spacers being
used to form a fenca.ng system. The fence is assembled by first
forming a relatively small fence hole 30, about 8 inches deep,
and then driving a steel pipe 214 into the center of the hole
and then down several feet into the earth. The pipe 214 is a 1
7/8 inch galvanized pipe as before but longer, suitably about
7 or 8 feet in length. The ground around the pipe is then dug
away to provide a hole having a depth of about 8 inches, large
enough to receive the post. Spacers 16 similar to those
described with reference to Fig.l are then slid over the pipe
214 and secured to the pipe with screws . An insulating material
such as Styrofoam (trademark) is then inserted into the ground
hole . The post 15 is then placed over the pipe and the spacers,
and its lower end is inserted into the hole 30 to a depth of
about 4 inches, so that the insulating material fills the lower
portion of the post. Following this, the ends of rails 220 are
mated with the sides of the post as described with reference to
Figs.3 and 4.
Fig.5A shows a variation in which a spacer 216 replaces
the Styrofoam 32. H.=re, a fence hole of 4 inches is dug
firstly, and the pipE: 214 :inserted. as before. Then, the long
spacer 216 is placed in position, and driven down to 8 inches
2.5 below the surface. '~'wo regular spacers 16 are then positioned
on the pipe, and attached to it by screws . The post is then
positioned, and driven down to about 4 inches below the ground
level.
Fig.6 shows a v<~riation using a circular post 215. The
spacer 216 used in this case is similar to spacer 16 previously
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described, except that the .flanges 217 on the outer ends of the
ribs 216b project ate an angle of close to 90° from the ribs, in
practice between about 80 and 90°, so that their outer edges
make contact with the interior of the post and provide an
interference fit in l;he post cavity. As before, the sides of
the post are routed to provide apertures for the rails 220.
In Fig.6 these are shown terminating at the spacer, but in many
cases the spacer will be used below the rails so that these can
extend fully to the support pipe 14. Also as before, the spacer
has internal ribs 218 which grip the pipe 14. Clearly, other
shapes of post coul~;a be used, such as hexagonal or polygonal.
It will be noted that in Figs.2 and 4, and in Fig.6, the
internal ribs 1.8 and 218 are situated between the external ribs
16b, 116b, and 216b, so that slight expansion of the tubular
member when fitted onto an oversized pipe does not greatly
change the diameter of the external ribs.
It will be seen that the spacer provided in accordance
with this invention allows .a well supported plastic railing or
fence system to be assembled with a few commonly available
parts, such as the pipes 14 or 214, and the special spacers 16,
116, 216, which can be formed ~>y extrusion and are only
required to be used in short lengths, as in Fig. 1.
While the major' components of t:he system, namely the posts
and rails, are preferably of extruded plastic, the spacer does
2!5 not have to be plastic and may be of extruded aluminum. Where
aluminum is used, the' flanges 17 on the spacer ribs 16b are
made thinner than for plastic, in order to be suitably
flexible.
