Screw piercable structural support for a planar substrate

A structural support for supporting a planar substrate, for example plywood, is provided with a screw receiving channel. The channel provides a guide simplifying screw attachment for a substrate to the support.

FIELD OF THE INVENTION 
The present invention relates to a structural support designed to secure 
and support a substrate used to form a wall or floor in a concrete forming 
system. 
BACKGROUND OF THE INVENTION 
It is standard practice in concrete forming to secure a substrate by means 
of a plurality of spaced apart fixed beams. These beams preferably are of 
an extruded aluminum or an aluminum composite. 
Each beam has a planar support for engaging the rear face of the substrate. 
The substrate sits on one side of the support and screws are passed from 
the other side at 90.degree. through the support into the substrate. 
According to conventional practice, beams have a series of punched holes 
spaced along the length of the beam. The series of holes are provided as a 
second manufacturing step before the beams are sent to a construction 
site. It is also known to drill the beam as required on the construction 
site although this is not efficient. 
The present invention addresses these problems and allows the use of a 
metal piercing screw thereby avoiding a drilling or punching step. Also 
the beam of the present invention can be manufactured at less cost and has 
an improved delivery cycle that can be critical in the construction 
industry. Self-drilling screws for metal are known which can be used with 
conventional beams to avoid the drilling or punching steps. Unfortunately, 
self-drilling screws have poor holding properties in the substrate. This 
is very important as this property determines the durability of the 
assembled beam and substrate. 
SUMMARY OF THE INVENTION 
The present invention provides a structural support for a planar substrate 
which has been particularly adapted to overcome the drawbacks noted above 
with respect to prior art beams. More particularly, the structural support 
for a planar substrate of the present invention has a platform one side of 
which is a substrate receiving face and the other side of which is a screw 
mounting side provided with a screw channel near an edge of the platform. 
The screw channel produces a thinning of the platform and acts as a guide 
for the securing screws. The thinned platform allows a metal piercing 
screw to be used, which screw has good holding properties with the 
substrate For example, a wood screw can pierce the thinned platform and 
provide a strong hold with the substrate. 
According to an aspect of the invention, the screw channel is angled to a 
position in which it is readily accessible without interference from the 
base of the support and such that the securing screw has on increased 
ability to hold the substrate.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIG. 1 shows a structural support system generally indicated at 1 for 
supporting a planar substrate 5. This system can be used in a horizontal 
position as shown in FIG. 1 where the substrate is intended to temporarily 
support a poured concrete floor or it can be used in a vertical position 
to provide temporary support for a poured concrete wall. 
The system relies on a plurality of structural supports generally indicated 
at 7 having the substrate attached to one side of the supports. 
In the preferred embodiment shown in FIGS. 1 and 2, each of the structural 
supports 7 has an I-beam construction or a channel-like construction. This 
construction includes a platform generally indicated at 9 at one side of 
the beam and a base generally indicated at 27 at the other side of the 
beam. The platform and the base are secured to one another by means of a 
main support web 25 at right angles to both the platform and the base. 
The base, as is known in the art, has an undercut channel or bolt slot 29 
for receiving a bolt head used to attach the base to the fixed support not 
shown. 
The key to the present invention resides in features provided at the 
platform 9 of the structural support. In particular, the one side 11 of 
the platform receives and supports the substrate 5 and the other side 12, 
i.e. the side to which the web 25 is secured, is a screw mounting side of 
the platform. Side 12 is provided with a screw guide channel 13 near each 
edge of the platform. The substrate receiving face 11 of the platform is 
also provided with a pair of channels 23 opposed to and separated from the 
channels 13 by means of relatively thin piercable webs 15 in the platform. 
The webs divide the platform into a main platform region or central 
substrate support section 17 on one side of each web and an edge region 21 
to the outside of each web. As will be clearly seen in FIG. 2, the edge 
region 21 is a peripheral rail which is substantially more robust than the 
web and provides reinforcement edgewise of the platform for the web 15. 
Any impact on the edge region which might otherwise damage the web is 
distributed by the edge region and avoids localized damage of the web. 
Although two screw receiving channels are shown, the support can be 
manufactured with a single channel, or three or more channels. 
In the preferred embodiment as shown, structural support 7 is extruded 
aluminum and substrate 5 is in the form of a piece of plywood supported as 
shown in FIG. 1 by a plurality of spaced apart structural supports. The 
securing of the substrate to the platform 9 of the structural support is 
provided by a series of screws such as wood screw 28 that pierces through 
the aluminum into the substrate. Washers 26 may be provided on the wood 
screws 28. 
As is clearly shown in FIG. 2, screws 28 are fitted into the screw channels 
13 where they pierce the webs 15 which are substantially thinner than the 
rest of the platform. This allows for a much easier piercing of the 
platform. In addition, the webs 15 are V-shaped coming to an apex to form 
an acute angled section for seating the tip of the screw and further 
easing passage of the screw through the web at the desired 45.degree. 
angle. 
As will be seen in the left hand side of FIG. 2, the screw produces burrs 
24 in the aluminum where it passes through the web 15. However, these 
burrs do not protrude above the flat substrate receiving face of the 
platform but rather are maintained in the channels 23. Furthermore, any 
burring which occurs on the screw mounting side of the platform occurs 
within the channels 13 so that a used support beam made in accordance with 
the present invention is much safer to handle than a used prior art beam 
where burring of the aluminum material occurs on an exposed surface where 
the beam might well be handled. 
Another novel feature of the present invention is found in the orientation 
or angling of the screw channels. As will be seen, the main region 17 of 
the platform has an end portion 19 which is a stub flange on one side of 
channel 13. This end portion is set at an angle and preferably a 
45.degree. angle relative to the main region of the platform. The other 
side of the channel is bordered by the robust peripheral rail edge region 
21 which is also angled at the mouth of the channel. The screw channel is 
therefore angled outwardly away from the main web of the beam at 
45.degree. to the platform. This angle allows good access for a power tool 
used to secure the screws. The peripheral rail 21 and the associated stub 
flange 19 provide bearing surfaces for contact with the fasteners. 
The angling of the two channels as described immediately above, produces a 
number of benefits. Firstly, it provides a very good working tool angle at 
each channel. For example, when working with a power screw driver for 
passing the screw through the beam platform, there is no interference with 
the base or web of the beam. In addition, the angling away from 90.degree. 
allows greater screw penetration into and more positive securing of the 
substrate to the support platform. 
Although the description above has been specific with respect to the use of 
plywood as the substrate and wood piercing screws as the fasteners it 
would be understood that other appropriate substrates and screws could be 
used. For example, the substrate could be in the form of a plastic 
substrate held by appropriate screws or fasteners. 
FIG. 3 shows a modified structural support generally indicated at 35. This 
support, like support 7, has a platform 38 with angled screw channels 37 
to one side of the platform and separated from burr channels 39 on the 
other side of the platform by V-shaped webs 41. However, in this case, 
support 35 is additionally provided at one of its reinforced edges with a 
substrate edge guide 43 extending outwardly at 90.degree. to the substrate 
receiving face of the platform. As will be understood, this particular 
structural support is only used along an edge of the substrate to protect 
the edge, whereas the structural supports 7 would be used away of the 
edges of the substrate. 
FIG. 4 shows a further modified structural support generally indicated at 
45. This structural support has a platform 47, one edge of which is 
provided with opposing screw and burr channels 49 and 51 respectively 
separated by a V-shaped web 53. The other side of the platform is void of 
any screw and burr channels but is rather provided with a substrate edge 
guide 55. 
The structural support configuration shown in FIG. 4 clearly demonstrates 
that the securing of the substrate need occur at one side only of the 
platform of the support. It also demonstrates that the support can be 
provided with a different type of base such as support base 61 used to 
secure the support to a different type of support member. 
Although various preferred embodiments of the present invention have been 
described in detail, it will be appreciated by those skilled in the art, 
that variations may be made without departing from the spirit of the 
invention or the scope of the appended claims.