Note: Descriptions are shown in the official language in which they were submitted.
CA 02436447 2003-08-05
SUPPORT FRAME FOR DUCT'
BACKGROUND OF THE INVENTION
1. TECHNICAL FIELD
s The present invention generally relates to heating, ventilation, and
air conditioning installations and, more particularly, to the supports used to
hold the air ducts in place. Specifically, the present invention relates to a
support frame for a duct that is installed in a vertical wall between studs.
to 2. BACKGROUND INFORMATION
Numerous aiE~ duct installations require a duct to be run in a vertical
wall. One such installation is a cold air return duct that is run from the
second floor of a house through the first floor wall into the basement. In
this case, the duct passes through an opening formed in the second floor
is floor boards and an opening formed in the first floor floor boards. A metal
duct is then positioned down or up through these openings between wall
studs. This vertical section of duct must be securely held in place. In the
past, the person installing the duct would have to fabricate custom holders
on the job site from scrap material and use these holders to secure the
2o vertical duct in place, Duct installers de sire ars improved support that
obviates the need to custom form supports in the field.
SRIEF SUMMARY OF THE INVENTION
The invention provides a support frame configured to fit between
2s wall studs. The support frame has a central opening adapted to receive a
vertical air duct. 'fhe central opening may be rectangular ~r oval. Both
openings are defined by upstanding flanges that are tilted inwardly toward
each other to provide a frictional fit with the duct. The flanges are
adjustable to accommodate ducts of different dimensions.
CA 02436447 2003-08-05
EXP~2ESS MAIL NO. EV256792020US
The invention also provides a frame having formed notches
adapted to receive standard studs to properly position the frame and
opening with respect to the studs.
s BRIEF DESCRIPTION OF THE SEVERAL v'IEWS OF THE DRAWINGS
Fig. 1 is a perspective view of the support frame for a duct made in
accordance with the concepts of the present invention.
Fig. 2 is a top plan view of Fig. 1.
Fig. 3 is a front elevation view of Fig. 2.
io Fig. 4 is a side elevation view of Fig. 2.
Fig. 5 is a perspective view of a section of floorboard, floor joists,
and wall studs with a duct opening formed in the floor boards between the
wall studs.
Fig. 6 is a view similar to Fig. 5 shovuing a section of vertical duct
is being disposed in the duct ~pening with the support frame of the present
invention being positioned between the wall studs.
Fig. 7 is a view similar to Fig. 6 showing the support frame of the
present invention in an installed position.
Fig. 8 is a top plan view of the assembly of Fig. 7.
2o Fig. 9 is a section view taken along line 9-9 of Fig. 8.
Fig. 10 is a front elevation view of the vertical duct extending
between a floor and a ceiling and held in place with a pair of the support
frames of the present invention.
Fig. 11 is a perspective view of the support frame for an oval duct.
2s Fig. 12 is a top plan view of Fig. 11.
Fig. 13 is a front elevation view of Fig. 12.
Fig. 14 is a side elevation view of Fig. 12.
Similar numbers refer to similar parts throughout the specification.
2
CA 02436447 2003-08-05
EXPRESS MAIL NO. EV256712020US
DETAILED DESCRIf~TION OF THE INVENTION
The support frame of the present invention is indicated generally by
the numeral 10 in tree accompanying drawings. Support frame 10 is used
s to hold the position of an air duct 12 in a wall 14 with respect to a floor
board 16 as shown in Fig. ?. Support frame 10 is preferably fabricated
from metal so that it will not burn or spread flames that may be disposed
inside air duct 12. Support frame 10 is conif'igured to fit befinreen the wall
studs 18 of wall 14 and center air duct 12 with respect to the duct opening
l0 20 defined by floor 16. The person installing air duct 12 may thus easily
p~sition the upper and lower ends of air duct 12 as shown in Fig. 10.
Support frame 10 is provided in at least two embodiments for rectangular
and oval ducts as sinown in Figs. 1 and 11. Each embodiment is capable
of supporting slightly different-sized ducts 12. Each embodiment is also
Is adapted to substantially seal duct opening 20 to prevent air from leaking
through duct opening 20 after air duct 12 is installed.
Support frame 10 includes a body 22 in the form of a thin plate.
Body 22 defines a ~:entral opening 24 adapted to receive air duct 12. As
such, opening 24 t,as an outer perimeter that i:> larger than the outer
2.0 perimeter of air duct 12 so that air duct '12 may readily slide through
central opening 24. Body 22 has a lengtllwise direction and opposed
ends at ends 26 at opposite ends of the lerlgthwi:>e direction of body 22.
Each end 26 define) a notch 28 that is adapi:ed to receive a portion of wall
stud 18. Central opening 24 is centered with respect to notches 28
2s allowing the user to properly locate central opening 24 with respect to
wall
studs 18 as depicted in Fig. 6. Body 22 thus extends beyond each wall
stud 18 as depicted in Fig. 7 so that duct opE~ning 20 is sealed by body 22
when support frame 10 is installed. In an alternative embodiment of the
3
CA 02436447 2003-08-05
EXPRESS IVIA4L NO. EV256712020US
invention, the overall length of body 22 may be reduced and notches 28
may be eliminated. In this embodiment, the person installing frame 10
determines the position of body 22 between studs 18.
Support frame 10 further includes a flange 30 that extends up from
s body 22 adjacent opening 24. Flange 30 is angled inwardly with respect
to opening 24 as ,shown in Figs. 2-4 and' 12-14. In the rectangular
embodiment of the invention depicted in Figs. 1-4, Mange 30 is provided in
the form of four flange sections 32 that are disposed on opposed sides of
rectangular opening 24. As depicted in Figs. 2-4, opposed flange sections
l0 32 are angled toward each other. Flange sections 32 may thus pivot with
respect to body 22 to accommodate differently-sized air ducts 12. The
pivoting nature of flange sections 32 also provide a biasing force against
air duct 12 to dampen vibrations and to help hold air duct 12 before
connectors 34 are csed to connect flange sections 32 to air duct 12. In
is the oval embodiment of support frame 10 depicted in Figs. 11-14, flange
30 is continuous about opening 24. Flange 30 is angled inwardly to define
a frustum as shown in Figs. 13 and 14. The angled nature of flange 30
allows flange 30 in the oval embodiment of support frame 10 to
accommodate air ducts 12 of slightly differing sizes. The angled nature
2o also creates a biasing force against air duct '12 frorn flange 30 to dampen
vibrations and to help hold air duct 12 in place before connectors 34 are
installed. In either embodiment, flange 30 may include tabs 36 that extend
from the upper end of flange 30. Tabs 36 are also angled inwardly as
depicted in Fig. 14 and provide additional biasing force and adjustment
2s capabilities to support frame 10. Each flange 36 defines at least one
connector opening 38 adapted to receive connector 32. In the preferred
embodiment, each Connector opening 38 is adapted to receive a sheet
metal screw 34 in a manner that allows they threads of the sheet metal
4
CA 02436447 2003-08-05
EXPRESS MAIL NO. EV256712020US
screw to bite into tab 36. Flange 30 and tabs 36 may also be trimmed with
appropriate cutters by the person installing air duct 12 if the outer
dimension of air duct 12 is too large to be received by flange 30. The user
may also cut slits into flange 30 to increase its flexibility if needed.
s Body 22 defines a plurality of connector openings 38 with a series
of openings disposed in opposed lengthwise directions along the opposed
lengthwise edges of body 22. Body 22 also defines one opening adjacent
notch 28. Openings 38 may be adapted to receive sheet metal screws as
described above or nails.
to Support frame 10 is used with a duct installation assembly as
shown in Figs. 5-10. Fig. 5 depicts the rough opening having ~pposed
wall studs 18 extending up from floor board 16 on either side of a duct
opening 20. The installer may position duct 12 up through opening 20 and
then slide support frame 10 down over the end air duct 12. The user may
is also first install support frame 10 by positioning notches 28 about studs
18
and securing body 22 to floor 16 with appropriate connectors in a nature of
screws or nails. In ~~ome cases, body 22 may also be secured with an .
appropriate adhesive. Once support frame 10 is secured, the user may
push duct 12 up through central opening 24 until air duct 12 is properly
2o positioned with respect to floor 15 and studs 18. The user may then
connect flange 30 to t~ir duct 12 with connectors 34 as depicted in Fig. 7.
Figs. 7 and 8 show how support frame 10 seals opening 20 to prevent
undesired airflow between different doors of the building. Fig. 10 shows
how air duct 12 is securely head by support frame 10 on different floors of
2s the building.
Although the installation drawings show support frame 10 used with
a rectangular duct, the same steps may be used to install an oval duct.
The oval embodiment of support frame 10 is also intended to be used with
s
CA 02436447 2003-08-05
EXPRESS MAIL NO. EV256712020US
round ducts by changing the shape of central opening 24 and flange 30.
In this application, the term oval includes shapes having straight sidewalls
and curved ends as shown in Fig. 12, circular shaped, and egg or elliptical
shapes.
s Body 22 may be fabricated in standard 16 inch lengths to fit
between standard vvall studs 18. The 16 inch length allows support
frames 10 to be used with adjacent studs without overlapping the ends of
body 22. The dimensions of central opening 24 may be varied so that
support frame 10 will work with different sized ducts 12. Central opening
io 24 should remain centered between .the ends and sides of body 22
regardless of the dimensions of central opening 24.
In the foregoing description, - certain terms have been used for
brevity, clearness, arad understanding. 1Vo ur'necessary limitations are to
be implied therefrom beyond the requirement of the prior art because such
is terms are used for descriptive purposes and are intended to be broadly
construed.
Moreover, the description and illustration of the invention is an
example arid the invention is not limited to the exact details shown or
described.
6
