Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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'ICHIMNEy CLOSURE APPARATUS "
B~CKGROUND OF THE INVENTION
This invention relates to new and useful improve-
ments in selectively closeable chimney apparatus for use on
*ireplace chimneys for the elimination of heat loss, down
drafts, cooling ef~ects and to improve draft conditions and
also to ass~st in the prevention of rain and snow penetration
down the chimney shaft.
Althoug~ it is designed primarily for use with fire-
places, nevertheless it will be appreciated that it can be
used for chimneys in other heating devices.
Fireplaces are usually eguipped with a damper locat-
ed just above the firebox and this damper is often damaged at
the time of installation or is affected by heat and differen-
tial movements in such a way as to allow relatively large
amounts of air movement when the fireplace is not in use and
the damper is closed.
There are three possible conditions for air movement
through a chimney:
1) A flow of air from inside the building to the out-
side resulting in energy loss.
2) A flow of alr down the chimney and into the en-
closed area, in which case the surrounding area
is cooled and uncomfortable, and
3) No movement at all (neutral equilibrium). For
this and fo~ condition #2, the total chimney and
'~
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surrounding material ~brick, blocks, liner, etc.)are cooled substantially. Thus by contactivity
they create a draft o~ cool air inside the room.
(Warm air comes in contact with the cool surface
of the face of the chimney or fireplace, and ad~a-
cent area, cools off and then circulates by con-
vection currents.
~ 11 of these conditions are variable for the same
unit depending upon weather conditions such as témperature,
wind, pressure ana the like, and the pressurization existing
within the building (furnace off or on, air supply for com-
bustion, clothes driers and the like).
Therefore most fireplaces have a stack of cold air
which comes down to the damper (for the case of neutral equi-
librium) and when an attempt is made to light a fire in the
fireplace, this column of cold air will prevent proper estab-
lishment of the necessary upward airflow The result is that -
smoke often enters the room and in many cases it is necessary
to preheat the chimney by burning newspaper or the like and
holding same at the base of the chimney until the up-draft is
established.
Water and snow penetration into the chimney can
cause damage to the joints of the flue liner by freezing and
thawing and can thus result in deterioration of the unit.
SUMMARY OF TE~E INVENTION
e present invention overcomes these disadvantages
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by elimi~nating or at least reducing the above mentioned pro-
blems. The ~nvention descri~ed is easily installed in new
and ex~sting fireplaces, does not freeze shut, does not inter-
~ere w;th the flow, does not cause turbulence, and provides
shelter from xain and snow and is also fail-safe inasmuch as
it will drop to the open position if the cables should fail.
The dev~ce is particularly useful in conserving
energ~ and provid~ng for better fireplace operation ana, of
course, providing for the extension of the life of the flue
liner and associatea structures.
In accordance with the invention there is provided
a selectively operated closure assembly for chimney flues
which include a flue liner; comprising in combination a frame
engageable within th.e upper discharge end of the ch.imney flueand, when installed, extending from the upper discharge end
downwardly to a location spaced below the upper discharge end,
means detachably supporting said frame within the upper dis-
- charge end of the chimney flue, a damper plate hinged to said
. frame adjacent the lower end thereof and movable from a clos-
ed position to an open position and vice versa, means adjacent
the lower end of the frame engageable by said damper plate
when in the closed position, means to control the position
of said damper plate relative to said frame and means where-
by said damper plate moves to the open position if said means
to control the position of said damper plate become inopera
tively disconnected from said damper plate, thereby resulting
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in a fail-safe open relationship of said damper plate relative
t:o said chimney flue.
Another advantage of the invention is to provide a
device of the character herewithin described which is simple
in construction, economical in manufacture and otherwise well
suited to the purpose for which it is designed.
It will be noted that if the cable breaks or be-
comes disconnected from the flap or p~ate, the flap will drop
open thus providing a fail-safe construction.
With the foregoing in view, and other advantages as
will become apparent to those skilled in the art to which this
invention relates as this specification proceeds, the inven-
tion is herein described by reference to the accompanying
drawings forming a part hereof, which includes a description
of the preferred typical embodiment of the principles of the
present invention, in which:
DESCRIPTION OF THE DRAWINGS
Figure 1 is an isometric view of the device per se
with the flap shown in a partially open or closed position.
Figure 2 is a vertical section showing the device
installed within the upper end of a chimney construction with
the flap in the closed position.
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In the drawings like characters of reference indi-
cate corresp~nding parts in the different figures.
DETAILED DESCRIPTION
Before proceeding with the description of this in-
vention, it will be appreciated that although the chimney and
the device are shown as having a rectangular cross sectional
configuration in Figures 1 and 2, nevertheless it will be
appreciated that a cylindrical or round configuration can be
used.
Proceeding therefore to describe the invention in
detail, reference should first be made to Figure 2 in which
reference character 10 illustrates the upper end of a
chimney with.a cap 11 and flue liner 12 all of which are
conventional.
As shown in Figures 1 and 2, the invention, collec-
tively designated 13, includes a rectangular base frame 14 of
a size just sufficient to slidably engage within the upper end
of the flue liner 12. This frame is preferably formed from
angle iron and is provided with a hinge 15 on one side thereof
to which a rectangular flap or damper plate 16 is hinged for
movement from a vertical, open position shown in phantom in
the drawings, to a horizontal or closed position shown in full
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li,ne în Flgure 2, under which circumstances, the plate en-
gages the horizontal flanges 17 of the rectangular frame. If
de~ired, a seal of material such as asbestos rope (not illus-
trated2 ~ay be secured around the undersiae of frame 14
against which the plate engages when closed.
Four rods 18 extend upwardly from the corners of
the frame to which they are welded or otherwise secured and
a small cross bar 19 is welded to each of the rods spaced up-
wardly from the frame and situated diagonally with reference
'to the right angled corners of the frame so that when the
frame is slidably engaged within the flue liner, these cross
bars engage the upper sides or ends of the flue liner and
support the frame as clearly shown in Figure 2.
A rain or snow shedding cap 20 is secured to the
upper end of the rods 18 by means of screws 21 ana extends
beyond the dimensions of the flue liner as shown in the draw-
ings, said cap having sides which slope upwardly and inward-
ly towards a common apex 22 as clearly illustrated.
A cable 23 is provided with one end extending dow~-
wardly through the flue liner,to a convenient location adja-
cent the fireplace (not illustrated), said cable being attach-
ed to adjacent the edge 24 of the damper plate 16 opposite to
the hinge 15. The cable then extends diagonally upwardly
and over a cross bar ~5 which acts as a sheave and which ex-
tends between two rods 18 secured to the corners of the frame
to which the flap'is hinged. The other end of the cable then
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ex-tends downwardly thro~lgh the flue liner to a position con- ,
ven~ent to the fireplace. An aperture may be provided in the
damper plate adjacent the hinge if desired.
When the cable end specificall~ designated 23A is
pulled, the flap is pulled open to the vertical position
against one side of the flue liner as shown in phantom ~n
~gure 1.
When the other end 23B of the cable is pulled, the
flap is raised to the horizontal or closed position under
which circumstances said other end 23B is detachably anchored
to a convenient location adjacent the fireplace.
,Alternatively, a weight (not illustrated~ may be
attached to the end 23B within the flue to close the damper
plate and hold same closed under which circumstances, the
end 23A must be detachably anchored when the damper plate is
in the open position.
The soot and other particulate materials contained
within the smoke of a fireplace coats the undersiae or hori-
zontal flanges 17 of the frame and the surfaces of the flap
so that when in the closed position, they assist in the seal-
ing relationship between the flap and the frame.
Any freezing which might occur during relatively
cold weather is easily broken by pulling on the cable 23A in
order to break the seal should this become necessary.
Although the frame is shown made of angle iron,
nevertheless it is desirable that the vertical flange 17A
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thereof be formed so that it inclines inwardly slightly thus
enabling packing such as asbestos, rope or string 14A to be
engaged between the back of the vertical flange and the flue
liner to give a relatively good seal at this point.
Since various modifications can be made in my in-
vention as hereinabove described, and many apparently widely
different embodiments of the same made within the spirit and
scope of the claims without departing from such spirit and
scope, it is intended that all matter contained in the
accompanying specification shall be interpreted as illus-
trative only and not in a limiting sense.