U.S. patent number 3,859,818 [Application Number 05/465,298] was granted by the patent office on 1975-01-14 for combination refrigeration and evaporative cooling air conditioner.
Invention is credited to William H. Goettl.
United States Patent |
3,859,818 |
Goettl |
January 14, 1975 |
COMBINATION REFRIGERATION AND EVAPORATIVE COOLING AIR
CONDITIONER
Abstract
The disclosure relates to a compact and unitary assembly of a
refrigeration air conditioner and an evaporative cooler air
conditioner wherein damper means is arranged with relation to the
delivery and return duct assembly of the refrigeration air
conditioner so that evaporative cooled air may be delivered from
the evaporative cooler, through both the delivery and return ducts
of the refrigeration air conditioning system when the refrigeration
air conditioner is not energized, and whereby the energization of
the refrigeration air conditioner and deenergization of the
evaporative cooler causes said damper automatically to be shifted
to close off the blower outlet opening of the evaporative cooler so
that normal refrigeration air conditioning may be accomplished by
the refrigeration air conditioner. The disclosure also relating to
several species of the invention which all relate to the use of the
aforementioned delivery and return ducts for concurrent delivery of
evaporative cooled air therethrough. The system is unitary and
adapted to be mounted on the upper side of a building roof so that
all of the equipment, including the damper mechanism may be above
the roof.
Inventors: |
Goettl; William H. (Scottsdale,
AZ) |
Family
ID: |
23847225 |
Appl.
No.: |
05/465,298 |
Filed: |
April 29, 1974 |
Current U.S.
Class: |
62/311; 62/314;
261/140.1; 62/309; 62/332 |
Current CPC
Class: |
F24F
5/0035 (20130101); F24F 5/0007 (20130101); Y02B
30/54 (20130101) |
Current International
Class: |
F24F
5/00 (20060101); F28d 005/00 () |
Field of
Search: |
;62/311,314,332,309,171
;261/14R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wye; William J.
Claims
I claim:
1. In a combination air conditioner adapted to be installed on top
of a building roof; an evaporative cooler; a refrigeration air
conditioner adjacent to said evaporative cooler; said refrigeration
air conditioner having a refrigerant evaporator; said refrigeration
air conditioner having first means for forcing air through said
refrigerant evaporator; a refrigerated air delivery duct extending
from said refrigerant evaporator to receive refrigerated air
therefrom; an air return duct adjacent to said delivery duct; said
return duct communicating with said first means; said first means
disposed to force air from said return duct and through said
refrigerant evaporator and into said delivery duct; a blower in
said evaporative cooler; said blower provided with a delivery
opening communicating with the interiors of both of said ducts; and
a pivoted damper pivotally disposed to swing into an open or closed
position relative to said blower delivery opening; said damper
alternately pivotal into an open or closed position relative to
said delivery ducts to thereby permit said blower to deliver
evaporatively cooled air concurrently through said delivery duct
and said return duct.
2. The invention defined in claim 1 wherein said delivery duct is
disposed uppermost in said duct assembly; said delivery duct having
upper and lower wall portions; said damper pivoted at said upper
wall portion of said delivery duct; said damper being pivoted at a
respective said of said blower delivery opening.
3. The invention as defined in claim 2 wherein said delivery duct
is provided with opposite side walls; said damper having opposite
edges speced from said opposite side walls to allow flow of
evaporatively cooled air into said delivery duct toward said
evaporator when said damper is in said closed position relative to
said delivery duct to thereby permit evaporatively cooled air to
flow progressively through said evaporator said first means and
said return duct; said damper when in open position relative to
said blower delivery opening having its free edge opposite to said
pivoted portion thereof; said free edge movable to said lower wall
portion of said delivery duct to allow evaporatively cooled air to
move from said blower delivery opening and into said delivery duct
extending downwardly therebelow whereby evaporatively cooled air
may be delivered to a room through both said delivery and return
ducts.
4. The invention as defined in claim 3 wherein said damper is
responsive to air flow from said first means when said blower is
deenergized whereby said damper is forced closed by air from said
first means thereby closing said blower delivery opening and
refrigerated air is then delivered from evaporator through said
delivery duct and returned to said evaporator through said return
duct.
5. The invention as defined in claim 1 wherein said evaporative
cooler and said air conditioner are fixed together in a unitary
assembly; support means carrying said unitary assembly; a roof
supporting said support means; interior delivery and return duct
means below said roof; said interior return and delivery duct means
communicating through said roof with said first mentioned return
and delivery ducts of said elbow shaped duct assembly.
6. The invention as defined in claim 1 wherein said evaporative
cooler is provided with evaporator cooler pads; said cooler having
sides, other than said upright sides, in which said evaporator
cooler pads are disposed; said evaporator cooler having a sump
portion near said bottom thereof said sump portion adapted to
contain water therein; said sump portion disposed in partically
surrounding relation to said elbow shaped duct assembly.
7. The invention as defined in claim 1 wherein said evaporative
cooler is mounted on top of said refrigeration air conditioner;
said blower of said evaporative cooler having a delivery opening
communicating with said refrigerant evaporator of said
refrigeration air conditioner and adapted to force evaporative
cooled air therethrough and into said delivery duct and
concurrently adapted to force air through said first means and into
said return duct; and a damper pivotally mounted in relation to
said delivery opening of said evaporative cooler for swinging into
closed position relative to when first means of said refrigeration
air conditioner is energized, said damper being freely pivotal to
an open position by air forced through said evaporative cooler
blower when it is energized and when said refrigeration air
conditioner is deenergized.
8. The invention as defined in claim 1 wherein said evaporative
cooler is provided with a side delivery blower opening
communicating with openings in sides of said delivery and return
ducts; and pivotal damper means coupled together and adapted to
swing open and close relative to said openings in the sides of said
ducts whereby evaporative cooled air from said blower of said
evaporative cooler may be delivered directly into said ducts for
concurrent delivery of evaporatively cooled air through both said
delivery and return ducts and whereby the damper means is forced
closed relative to the delivery opening of the evaporative cooler
blower when said first means is energized for forcing air through
said refrigerant evaporator to deliver refrigerated air through the
delivery duct and allow air to return through said return duct to
said first means.
Description
BACKGROUND OF THE INVENTION
For many years, the air conditioning industry in substantially arid
regions has recognized the advantages of refrigerated air
conditioning as compared to evaporative cooling and many of the
companies installing air conditioning have primarily considered the
installation of refrigeration.
It has been well known that evaporative coolers are very effective
during periods when the relative humidity is low and evaporative
coolers are relatively inexpensive to operate due to the relatively
low power requirements, all of which generally saves energy and
cost of operation to the owner.
In many areas the weather includes certain periods in which the
relative humidity is quite low and during such periods evaporative
cooling is entirely satisfactory. However, in the same areas and
during other seasons of the year humidity becomes very high and at
the same time, the ambient temperature is high. Accordingly, during
such periods refrigeration air conditioning is required due to the
fact that evaporative coolers do not provide for the comfort
necessary in air conditioned areas.
Accordingly, during low humidity periods it has been found that
evaporative cooling is very satisfactory while it is not generally
satisfactory during high humidity periods when refrigeration air
conditioning is very effective. Accordingly, various attempts have
been made to provide a compact and efficient combination air
conditioner, including both refrigeration and evaporative
cooling.
The prior art contains a variety of such arrangements, many of
which are bulky and require various dampers or slide valves which
may be installed in various areas of a building. Furthermore,
various systems which have been designed primarily for
refrigeration do not have sufficient cross-sectional area in the
ducts to accommodate the volume flow required for effective
evaporative cooling.
SUMMARY OF THE INVENTION
The present invention comprises a novel, compact and unitary
assembly of a refrigeration air conditioner and an evaporative
cooler air conditioner wherein a novel damper means is arranged
with relation to the delivery and return duct assembly of the
refrigeration air conditioner so that evaporative cooled air may be
delivered from the evaporative cooler, through both the delivery
and return ducts of the refrigeration air conditioning system when
the refrigeration air conditioner is not energized, and whereby
energization of the refrigeration air conditioner and
deenergization of the evaporative cooler causes said damper
automatically to be shifted to close off the blower outlet opening
of the evaporative cooler so that normal refrigeration air
conditioning may be accomplished by the refrigeration air
conditioner.
One species of the invention comprises a duct and damper assembly
which is generally elbow shaped and extends from a generally
upright side of the refrigeration air conditioner in a downwardly
direction through a lower portion of the evaporative cooler and the
refrigeration delivery duct of the elbow assembly is generally
uppermost and communicating therewith is an outlet of a blower of
the evaporative cooler with a damper at the juncture of the outlet
and the refrigeration delivery duct, the damper being pivoted to
the upper wall of the refrigeration delivery duct and adapted to
swing free at its lower edge so as to alternately close the
evaporative cooler blower and to partially close the delivery duct
between the blower and the refrigerant evaporator of the
refrigeration system so that when the damper is open relative to
the evaporative cooler blower. Evaporatively cooled air may pass
into the delivery duct toward a room and also in the opposite
direction through the delivery duct backwardly through the
refrigerant evaporator of the refrigeration air conditioner and
through its respective blower and into the return duct and then in
a direction toward the room, thereby allowing evaporatively cooled
air to be delivered through both the delivery and return ducts of
the refrigeration air conditioner system.
The combination air conditioner of the invention is adapted to be
mounted on top of a building roof with all of its components
thereabove and to communicate with return and delivery ducts which
are interior ducts in the building. The evaporative cooler is
provided with a water-containing sump partially surrounding the
elbow shaped duct assembly which comprises the delivery and return
ducts of the refrigeration air conditioner and a generally upright
side of the evaporative cooler adjacent to a respective upright
side of the refrigeration air conditioners, is disposed at the
connection of the delivery and return ducts of the refrigeration
air conditioner and the evaporative cooler in its remaining
generally upright walls is provided with evaporative cooling pads
which are substantially conventional evaporative cooler pads.
Other species of the invention comprise various mechanical
arrangements of the blower outlet damper with relation to the
delivery and return ducts of the refrigeration air conditioning
system so as to permit the evaporative cooler to deliver
evaporative cooled air through both the return and delivery ducts
and to provide automatic operation of the damper so that it will
open when the evaporative cooler is energized and closed when the
refrigeration air conditioning is energized as desired.
Operation of the combination air conditioner of the invention may
automatically take place with energization of the evaporative
cooler blower and concurrent deenergization of the refrigeration
air conditioner, or refrigeration cooling may take place
automatically by energization of the refrigeration air conditioner
and deenergization of the blower of the evaporative cooler and a
damper in the delivery duct of the refrigeration air conditioner
system is automatically opened with respect to the outlet of the
evaporative cooler blower when it is energized and the damper is
automatically closed relative to the outlet of the evaporative
cooler blower when the refrigeration air conditioner is energized.
The combination air conditioner of the invention provides for many
advantages such as the economy of evaporative cooler operation
during periods of low humidity and also the convenience of having
refrigeration readily available without delay when atmospheric
conditions become substantially humid and generally such that
evaporative cooling is not efficient.
Accordingly, it is an object of the present invention to provide a
novel combination refrigeration and evaporative cooling air
conditioner which provides for the saving of power and energy as
compared to the year-round use of conventional refrigeration air
conditioning system.
Another object of the invention is to provide a novel, compact
combination refrigeration and evaporative cooling air conditioner
wherein a novel, generally elbow shaped duct assembly comprises a
delivery and return duct means for a refrigeration air conditioner
which is shared by an evaporative cooler due to a novel damper
arrangement which automatically swings open or closed in either of
two directions, depending upon which of the units is being
operated, namely, the refrigeration air conditioner or the
evaporative cooler.
Additionally, it is an object of the present invention to provide a
novel combination refrigeration and evaporative cooling air
conditioner wherein a damper operating between an evaporative
cooler blower outlet and a refrigeration delivery duct, is so
arranged that the damper allows flow of evaporatively cooled air to
move in both directions in the delivery duct so that air flows
directly from the evaporative cooler blower to an interior duct of
a room, and also in the opposite direction toward the refrigeration
evaporator and through it and into the conventional return duct so
that evaporatively cooled air is delivered through both the
refrigeration delivery duct and return duct to a room thereby
providing substantial capacity for air flow of the evaporative
cooler, the requirements of which are greater than that of the
refrigeration air conditioner alone.
An additional object of the invention is to provide a variety of
species of the invention for accomplishing automatic operation of a
damper to allow the evaporative cooler of the invention to deliver
evaporative cooled air through both the return and delivery ducts
of the refrigeration air conditioner and to provide for automatic
operation of the damper so that either evaporative cooling or
refrigeration may be accomplished by energizing and deenergizing
the respective units and whereby the damper will respond
accordingly and automatically.
Further objects and advantages of the invention may be apparent
from the following specification, appended claims and accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a combination refrigeration and
evaporative cooling air conditioner;
FIG. 2 is an enlarged side-elevational view of said air conditioner
on a roof and showing portions thereof broken away and in section
to amplify the illustration;
FIG. 3 is a vertical sectional view taken from the line 3--3 of
FIG. 2;
FIG. 4 is a view similar to FIG. 2 showing a modification of the
invention with the evaporative cooler mounted up on top of the
refrigeration air conditioner;
FIG. 5 is a top or plan view of a further modification of the
invention showing portions broken away and ensectioned to amplify
the illustration;
FIG. 6 is a fragmentary section of view taken from line 6--6 of
FIG. 5; and
FIG. 7 is a fragmentary section of view taken from line 7--7 of
FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As shown in FIG. 1, a substantially conventional refrigeration air
conditioner 10 is provided with a substantially upright side 12
contiguous with a respective upright side 14 of a substantially
conventional evaporative cooler 16.
The refrigeration air conditioner 10 at its upright side 12 is
provided with a refrigerant evaporator 18 which is a substantially
conventional evaporator consisting of tubular refrigerant conduits
with heat conductive fins thereon.
This evaporator 18 communicates with an outlet duct 20 of a blower
22, the inlet of which communicates with a return duct 24.
The return duct is defined by a wall 26 at its upper portion and a
wall 28 disposed at its lower portion.
The refrigerant evaporant 18 communicates with a delivery duct 30
having an upper wall 32. The delivery duct 30 is provided with a
lower wall 34 which is the opposite side of the intermediate wall
26, which is the upper wall of the return duct 24.
The return duct 24 communicates with an interior return duct 36 and
the delivery duct 30 communicates with an interior delivery duct
38. These interior delivery ducts 36 and 38 communicate with the
interior of a room below a roof 40 on which the air conditioner is
mounted by a conventional mounting frame 42.
The evaporative cooler 16 is provided with a housing 44 having
three sides 46, 48 and 50 in which respective evaporative cooler
pads 52, 54 and 56 are mounted. These are substantially
conventional evaporative cooler pads assembly. And these sides
comprise three sides of the evaporative cooler housing 16 in
addition to the fourth side 14 which is contiguous with the
substantially upright side 12 of the refrigeration air conditioner
10.
The evaporative cooler 16 is provided with a blower 58 of the
conventional contrifugal type, and the blower is provided with a
downwardly directed delivery outlet 60 which is directed toward a
bottom or lower portion 62 of the evaporative cooler 16 wherein a
sump pan 64 partially surrounds the generally elbow whaped duct
assembly which comprises the delivery and return ducts 30 and 24
respectively.
At a lower portion of the delivery outlet 60 the blower is provided
with a blower outlet opening 66 which is adapted to be opened or
closed by a pivoted damper 68. The damper 68 is hinged at 70 to the
upper, inner portion of the delivery duct wall 32. The damper 68 is
provided with free swinging lower edge 72 adapted to move in
opposite directions as indicated by arrows 74 either into closed
position with respect to the blower outlet 66 or into engagement
with the generally lower wall 34 of the delivery duct 30 which is
uppermost in the assembly comprising the generally elbow shaped
assembly of the delivery and return ducts for the refrigeration air
conditioner.
The damper 68, shown in FIG. 3 of the drawings, is provided with
opposite edges 76 and 78 spaced from side wall portions 80 and 82
respectively of the delivery duct 30 so that air may flow around
the damper 68 when in the broken line position shown in FIG. 2 of
the drawings, and pass in the direction of an arrow A in FIG. 1
toward the evaporator 18 and in this position the damper also
allows air to flow in the delivery duct 30 in the direction of an
arrow B, all as will be hereinafter described in detail.
As shown in FIG. 3, it will be seen that the lower edge as well as
the side edges 76 and 78 of the damper 68 overlie the evaporative
cooler blower delivery 66 so that when the damper is in the solid
line position shown in FIG. 2, the delivery opening 66 is fully
enclosed.
In the closed position, as shown by solid lines in FIG. 2 of the
drawings, the damper 68 thus shuts off flow of air from the blower
58 and under such conditions, the blower 58 is deenergized and the
blower 22 is energized. In this mode of operation, arrows C
represent flow passing upwardly from a room through the return duct
24 and through the blower 22 and the refrigerant evaporator 18 and
into the delivery duct 30 such that the arrows C indicate a
continuous flow through the return duct 24 toward the evaporator 18
and through it and then back through the delivery duct 30 and into
a room.
Under this mode of operation, air pressure delivered by the blower
22 holds the damper 68 closed against the outlet opening 66 of the
evaporative cooler blower 58.
When the refrigeration air conditioner is deenergized the blower 22
thereof remains in static condition and when the evaporative cooler
blower 58 is concurrently energized, it forces the damper 68 into
the broken line position as shown in FIG. 2 of the drawings,
whereupon evaporatively cooled air from the evaporative cooler pads
52, 54 and 56 passes through the blower 58 downwardly through the
outlet opening 56 and through the delivery duct as indicated by the
arrow B and also around opposite edges 76 and 78 of the damper 68
and through the refrigerant evaporant 18 and its respective blower
22 and downwardly through the delivery duct 24 to a room, all as
indicated by the arrows A. In the forgoing manner the damper 68,
when open, permits the blower to communicate concurrently with both
the delivery and return ducts.
Accordingly, it will be understood that the volume requirements of
evaporative cooler air flow from the blower 58 are met by using
both of the delivery and return ducts 30 and 24 respectively due to
the fact that the damper allows part of the evaporatively cooled
air to pass through the refrigerant evaporant 18 and the blower 22
and into the return duct 24 so that air from the evaporative cooler
blower 58 passes through both the delivery and return ducts 30 and
24 and into a respective room below the roof 40.
The disposition of the generally elbow shaped duct assembly
comprising the delivery duct 30 and the return duct 34 disposed
within a portion of the evaporative cooler 16, permits the adjacent
generally upright sides 12 and 14 of the air conditioner and
evaporative cooler 10 and 16 respectively to be secured together in
a unitary and compact relationship and readily adapted for
installation above a roof 40 so as to contain all of the means
required for automatic operation of either of the units alternately
to provide for evaporative coolings or refrigeration as
desired.
The evaporative cooler 16, when in operation serves very
efficiently during low humidity condition, while the refrigeration
air conditioner 10 serves efficiently during relatively high
humidity ambient conditions. Accordingly, the function of the
combination air conditioner since such air conditioners cost a
great deal more to operate from a power standpoint than to
conventional evaporative coolers.
The compactness of the invention may be appreciated due to the fact
that the elbow shaped duct assembly passes outward and downward
through the evaporative cooler and the compact damper arrangement
provided by the damper 86 in the return duct 30 provides a means by
which air flow from either of the air conditioning units may
operate the damper in its respective direction and this may be
accomplished by simply utilizing a switch which concurrently
energizes blower 58 and deenergizes the blower 22 or vice versa,
depending on whether evaporative cooling is required or whether
refrigeration is required.
It will be understood that the refrigeration air conditioner is
provided with an air-to-air cooled condenser which receives air
through a grill 11 as shown in FIG. 1 of the drawings, and exhausts
air to atmosphere through an outlet 13. This refrigerant air
conditioner also provides a conventional refrigerant compressor in
circuit with the evaporator 18 and the usual condenser which is
disposed in a location next to the grill 11 hereinbefore
described.
In the modification as shown in FIG. 4, a refrigeration air
conditioner 80 is similar to the hereinbefore described
refrigeration air conditioner 10 and an evaporative cooler 82 is
similar to the hereinbefore described evaporative cooler 16.
the evaporative cooler 82, however, has evaporative cooler pads on
all four sides and the bottom of the evaporative cooler rests on
top of the refrigeration air conditioner 80 and is secure
thereof.
The evaporative cooler 82 is provided with a blower 86 having a
downwardly directed delivery outlet duct portion 88 which
communicates with an opening 90 in the upper side of refrigeration
air conditioner 80. A damper 92 is pivoted at 94 to swing into a
closed broken line position 96 or into the solid line position
shown in FIG. 4 against a stop 98 carried by a wall 100 internally
of the refrigeration air conditioner 80.
The opening 90 is disposed at and communicating with an inner side
102 of a refrigerant evaporative 104 which is similar to the
hereinbefore described evaporator 18.
A delivery duct 106 communicates with the evaporator 104 to receive
refrigerated air from the evaporator in the direction of the arrows
108 which air is driven by a blower 110 adapted to receive air
through a delivery duct 112 in the direction of arrows 114.
In operation when the evaporative cooler blower 86 is energized,
evaporatively cooled air is forced downwardly causing the damper to
open against the stop 98 and allowing air to flow downwardly and
through a refrigerant evaporative 104 and into the delivery duct
106 in accordance with the flow disposed by arrows 108.
Concurrently evaporative cooled air flows downwardly around the
damper 92 and through the blower 110 and proceeds into the delivery
duct in the direction of arrows 116, whereby evaporative cooled air
may be delivered through both the delivery and return ducts 106 and
116 respectively when the evaporative cooler 82 is energized and
when the refrigeration air conditioner is deenergized.
Conversely when the evaporative cooler 82 is deenergized and the
refrigeration air conditioner 82 energizes the blower 110 forces
air through the return duct 112 in the direction of the arrows 14
and delivers air upwardly forcing the damper 92 to exclosed broken
line position 96 and forcing air through the refrigerant evaporator
from the side 102 and into the delivery duct 106 whereby
refrigerated air is delivered through the duct 106 and air is
returned from the respective room as indicated by arrows 114
through the return duct 112.
The species shown in FIG. 4 provides for concurrent communication
of the evaporative cooler blower with both the delivery and return
ducts which communicate with the refrigeration air conditioner
A.
In the modification of the invention as shown in FIGS. 5, 6 and 7 a
refrigeration air conditioner 120 is similar to the refrigeration
air conditioners 10 and 80 and an evaporative cooler 122 is similar
to the hereinbefore described evaporative coolers 16 and 82. The
evaporative cooler 122 is provided with a side delivery blower
having a delivery duct 124 adapted to deliver evaporative cooled
air. This duct 124 as shown in FIG. 7 is substantially horizontal
duct flared to communicate with respective openings 126 and 128 in
delivery and return ducts 130 and 132 respectively as shown in FIG.
6 of the drawings. A shaft 134 extends downwardly through the
delivery and return ducts 130 and 132 and carries a pair of damper
members 136 and 138 which are fixed to the shaft 134 and cooperate
respectively with the blower outlet openings 126 and 128. These
dampers 136 and 138 are movable from the solid line position shown
in FIGS. 5 and 6 to broken line positions 140 and 142 respectively
to overly and cover the respective openings 126 and 128.
In operation when the refrigeration air conditioner 128 is
energized, air is forced from the respective air conditioner blower
144 shown in FIG. 6 through the refrigerant evaporator 146 and into
the delivery duct 130 in the direction of arrows 148. Air returns
through the return duct 132 in the direction of arrows 150 and when
the refrigeration air conditioner 120 is deenergized and the
evaporative cooler blower is energized evaporative cooled air is
delivered through the blower duct 124 which forces the dampers 136
and 138 fixed to the shaft 134 to pivot in bearings 152 and 154 to
the solid line position as shown in FIG. 5 of the drawings so that
evaporative cooled air is delivered directly from the blower
through the side openings 126 and 128 and into both the delivery
and return ducts 130 and 132 concurrently. According to this
particular species of the invention evaporatively cooled air does
not flow through the refrigerant evaporator 146 or the respective
blower 144.
It will be appreciated that when the blower 144 is energized and
the blower 124 is deenergized that flow of refrigerated air will
cause the damper 136 to swing close to a broken line position 160
shown in FIG. 5 of the drawings. Inasmuch as the damper 138 is also
fixed to the shaft 134, it will also close before substantial flow
through the return duct 132 occurs according to arrows 150.
All of the dampers namely the damper 168, the damper 92 and the
dampers 136 and 138 may have conventional magnetic holding devices
for holding them in close position relative to the evaporative
cooler blower outlets if desired and which magnets are capable of
being overcome by force of air passing from the evaporative cooler
blower when it is energized.
It will be obvious to those skilled in the art that various
modifications may be resorted to without departing from the spirit
of the invention.
* * * * *