Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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BACKGROUND OF THE INVENTION
Field of the Invention
This invention relates to a valve assembly for use with air
exchanging apparatus; that is, apparatus which exchanges room air
with fresh outside air.
Description of the Prior Art
With the increased recognition of the need for exchanging
stale (and sometimes toxic) air within a room or other enclosure
! with fresh air from the outside, there have developed a variety
of devices for accomplishing that exchange. One such device uses
a slowly rotating heat recovery rotor through which parallel, but
separate, air streams pass in countercurrent flow. ~nother such
device employs a two-position valve for reversing air flow in
ducts leading into the device from the outside.
All of these air exchanging devices have as part of their
operation a step in which air within a room or enclosure is
exhausted to the outside. There is, therefore, the possibility,
depending upon the structure of the device and its mode of
operation, for stale exhaust air to be immediately drawn back
into the air exchange device as "fresh" air. This occurrence may
result from an inadequate porting arrangement to the outside air
where stale air being exhausted remains in the vicinity of the
fresh air inlet port or from inordinately long exhaust ducts
leading to the outside, thereby creating a situation where stale
air, instead of being exhausted to the outside, moves back and
forth within an extended duct during cycling of the air
exchanging device.
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The present invention is intended to overcome the foregoing
problems by providing a valve assembly which minimizes the co-
mingling of exhaust air with fresh air.
SUMMARY OF THE INVENTION
I The present invention provides apparatus comprising ducting
to define two separate flow channels to outside air, one of the
channels being an intake channel having a normally closed valve
actuatable to the open position by the flow of intake air there-
through, and the second of the channels being an exhaust channel
10 I having a normally closed valve actuatable to the open position by
the flow of exhaust air therethrough.
Other objects and advantages of the present invention will
become apparent from the following detailed description taken
with the accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
,
FIG. 1 is a top plan view of an embodiment of the present
invention;
FIG. 2 is a front elevational view of the assembly shown in
FIG. 1 as viewed from the bottom of that figure,
FIG. 3 is a side elevational view of the FIG. l;
FIG. 4 is a sectional view taken along the line IV-IV of
FIG. 2; and
FIG. 5 is a fragmentary section view taken along the line
V-V of FIG. 2.
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, there is shown an assembly,
generally designated by the reference numeral 10, constructed
in accordance with the present invention. Assembly 10 is shown
in the drawings as installed in the duct 20 which leads from an
air exchanging unit 30 (only part of which is shown in the
drawings). As indicated by the air flow arrows in duct 20, air
exchanging unit 30 operates in cyclic fashion so that duct 20
is an intake duct during one part of the cycle and an exhaust
duct during the other part of the cycle. The air thus
alternatively flows through heat storing matrix 40 of air
exchanging unit 30. Duct 20 extends through a wall 50 of an
enclosure to the outside. A filter 60 is disposed within duct
20 to prevent the passage of relatively course particulate
matter.
Because the cycle time of air exchanging unit 30 is about
four seconds, there is concern that the same stale room air
exhausted through duct 20 during the two second exhaust period
will be drawn into duct 20 when the two second intake period
commences (and vice-versa with respect to fresh air). The
purpose of assembly 10 is to minimize that possibility. It
will be understood that while duct 20 is shown as having
alternating air flow, it could be a dedicated exhaust duct from
an air exchanging unit which cycles to intermittently exhaust
air through that dedicated duct.
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Assembly 10 is adapted to mate with the duct 20. Assembly
10 comprises a boxlike structure having a central partition 104
which divides assembly 10 into two separate air flow channels
1 106, 108. Channel 106 serves as the flow channel for intake
I fresh air drawn from the outside through port 107 and channel 108
serves as the flow channel for stale room air being exhausted to
the outside through port 109. Ports 107, 109 are arranged to be
~ivergent from one another to minimize co-mingling of air flowing
I through each port. Baffles 110, 112 extend from the distal ends
of ports 107, 109, respectively, to the distal end of partition
104, these angularly arranged baffles serve to smoothly transi-
tion air flowing in channels 106, 108 through a ninety degree
turn with respect to ports 107, 109.
' Disposed adjacent the inboard ends of air channels 106, 108
are a pair of pivotally mounted shutters 114, 116. As best shown
in FIG. 2, shutters 114, 116 are pivoted on a horizontal axis 118
upwardly displaced from the vertical midpoint of assembly 10.
Each of shutters 114, 116 has a counterweight assembly 120
comprising a bolt or screw member 122 with an axially movable
weight 124 either slidably or threadedly mounted thereon.
Mounted in each of the sidewalls of assembly 10 is a stop pin 126
which prevents the associated shutter from rotating more than
ninety degrees.
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When air exchanging unit 30 is operating in the fresh air
intake mode, the force of the air flowing in intake channel 106
strikes intake shutter 114 and causes the bottom portion of
shutter 114 to rotate upwardly (see FIG. 5). Exhaust shutter
1 116, on the other hand, is prevented from rotational movement by
the presence of lug 130 and the location of counterweight 120
j below the pivotal axis of shutter 116; thus there is no air flow
in exhaust channel 108. Counterweight 120 on intake shutter 114
may be adjusted to assure that shutter 114 moves easily by
adjusting weight 124 away from shutter 114 as the force of the
intake air is diminished. Shutter 114 is prevented from over-
travel by stop pin 126. When the intake cycle is completed and
air ceases to flow from port 107, the offset pivotal mounting
~ causes shutter 114 to return to its vertical position where it is
. stopped from further rotation by lug 128.
As the exhaust cycle is commenced in air exchanging unit 30,
air flowing through duct 20 strikes shutters 114, 116. Shutter
114 is prevented from inward rotation by lug 128 so no air flows
through intake channel 106. Shutter 116, on the other hand, is
free to rotate and does so by the bottom portion swinging into
exhaust channel 108 and upwardly against its corresponding stop
pin 126. The movement of shutter 116 can be aided by moving the
weight 124 on its counterweight assembly 120 closer to shutter
116. When the exhaust cycle ends, shutter 116 returns to its
vertical position against lug 130, aided by the presence of
counterweight assembly 120. It thus may be seen that assembly 10
minimizes the mingling of stale exhaust air with the source of
fresh intake air.
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It will be appreciated by those skilled in the art that
intake and exhaust channels 106, 108 may be physically separated
from each other when conditions so require; nevertheless, the
i actuation of shutters 114, 116 in response to air flow through
S those channel= occurs in the manner described above.
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