Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02775519 2012-04-27
AUXILIARY VENT COVER
This invention relates to an auxiliary vent cover for use on a conventional
dryer or
other vent assembly for venting air and other fluids from a building.
Conventional dryer or household fan vent assemblies include a flexible,
accordion duct connected to the dryer or fan, a thin-walled, metal pipe on the
outer end
of the duct for extending through the wall of a building and a vent cover
mounted on the
outer end of the metal pipe. The vent cover is usually a molded plastic body
carrying a
plurality of louvers, which are free to rotate between open and closed
positions. When
the dryer or fan is operating, the louvers pivot to open positions to
discharge air and
other fluids from the assembly and, when the dryer or fan is not in operation,
the louvers
fall back to the closed positions.
It has been found that under some windy conditions the louvers flap open and
closed even when the dryer or fan is not operating. Moreover, it is not
unusual for the
louvers to become stuck in the partly opened position. In the absence of
exhaust air
pressure, open louvers permit the entry of insects such as bees or wasps and
small
birds into the vent assembly.
The present invention provides a solution to the above-described problem in
the
form of an auxiliary vent cover which prevents louver flapping even under
strong winds.
In general terms, the vent cover of the present invention includes a frame and
louvers
which are similar to the frame and louvers of a conventional vent cover. The
frame is
defined by a front wall, a top wall, a bottom wall and side walls. The top,
bottom and
side walls flare outwardly and rearwardly from the front wall. The rear edges
of at least
some of the bottom and side walls have elongated notches extending along
almost their
1
CA 02775519 2012-04-27
entire length. The auxiliary vent cover is larger than a conventional vent
cover so that
when the auxiliary vent cover is placed over an existing wall-mounted vent
cover, there
is a space between the covers. A wind sufficiently strong to open the louvers
of the
outer auxiliary vent cover passes between the bottom and side walls of the two
vent
covers and is exhausted via the notches. Thus, flapping of the inner,
conventional vent
cover louvers is prevented.
The invention is described in greater detail with reference to the
accompanying
drawings, which illustrate a preferred embodiment of the invention and
wherein:
Figure 1 is an exploded, isometric view of a conventional vent cover assembly
and the auxiliary vent cover of the present invention;
Figure 2 is an isometric view of the auxiliary vent cover of Fig. 1 as viewed
from
the rear and one side; and
Figure 3 is a longitudinal sectional view of the auxiliary vent cover of Figs.
1 and 2 in the use position covering a conventional vent cover.
With reference to Fig. 1, a conventional vent assembly indicated generally at
1
includes a metal pipe 2 and a plastic cover 3 is connected to the outer end of
the pipe 2
for mounting the assembly on the wall of a building (not shown). When the
assembly is
mounted on a wall, the pipe 2 extends through a hole in the wall into the
building. A
flexible dryer or fan exhaust duct (not shown) is connected to the inner end 4
of the pipe
2.
The plastic cover 3 includes a generally rectangular frame 6 with an opening 7
therein. The opening 7 is normally closed by a plurality of louvers 8
pivotally mounted in
the frame. When the dryer or fan is in operation, air from the dryer or fan
passes
2
CA 02775519 2012-04-27
through the conduit and the pipe 2, causing the louvers 8 to open for venting
the air.
When the dryer or fan stops, the louvers 8 close to prevent birds or insects
from
entering the cover 3 and the pipe 2.
As mentioned above, the inventor has found that even when the dryer or fan is
not operating, when there is a strong wind the louvers 8 flap open and closed.
Each
time they close, the louvers 8 make a somewhat loud noise. Moreover, when the
louvers 8 are open, insects can enter the cover 3.
The auxiliary vent cover of the present invention which is indicated generally
at
includes a plastic body 11 defined by a front wall 12, a top wall 13, a bottom
wall 14
10 and side walls 15. Holes 16 are provided in the corners of the front wall
12 for receiving
screws or other fasteners. As best shown in Fig. 2, the top wall 13, the
bottom wall 14
and the side walls 15 flare outwardly and rearwardly from the front wall 12. A
rectangular frame 17 integral with the body 11 pivotally supports a plurality
of louvers 18
for rotation between the open and closed positions illustrated in Figs. 2 and
3,
respectively. The top wall 13 of the body 11 has a straight edge 20 parallel
to the front
wall 12 for tightly engaging the wall of a building (not shown) on which the
vent cover 1
is mounted. An elongated notch 21 is provided in the rear edge of each of the
bottom
wall 14 and the side walls 15. It will be appreciated that the notches could
be replaced
by slots or other openings in the bottom wall 14 and the side walls 15. A
plurality of
triangular ribs 23 are provided on the inner surface of each of the bottom
wall 14 and
the side walls 15. The ribs 21 are spaced a short distance apart, for example
one
eighth inch for preventing insects and small birds entering the vent cover via
the
grooves 21.
3
CA 02775519 2012-04-27
In use, the auxiliary vent cover 10 is mounted on an exterior building wall
over
the regular vent cover 1. When the dryer or fan is operating, the louvers 8
and 18 open
to discharge air from the building. When the dryer or fan is not operating,
the louvers 8
and 18 remain in the closed position shown in Fig. 1. As mentioned
hereinbefore, under
windy conditions when using the vent cover 1 alone, the louvers 8 can flap
open and
closed. With the auxiliary vent cover 10, even under quite windy conditions,
the louvers
8 remain closed. If the wind causes the louvers 18 to open as shown in Fig. 3,
the wind
passes between the ribs 23 and is discharged through the notches 21 in the
bottom wall
14 and the side walls 15 of the cover 10. In other words, the auxiliary vent
cover 10
relieves air pressure on the vent cover 3. Wind from the side or bottom of the
auxiliary
cover 10 can enter the cover creating pressure on the louvers 8 of the cover 3
and
opening the louvers 18 allow air and other fluids to escape from the auxiliary
cover.
4
