Note: Descriptions are shown in the official language in which they were submitted.
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BAC~G OUND OF THE INvENlrIoM
FIELD OF_THE INVENTION
This invention in its preferred embodiment
pertains to a refrigerated cooler having a relatively high
efficiency inle-t and outlet and air path -Eor ambient air
for the refrigaration system high side, and to a refriger-
ated cooler having high efficiency cooling of an evaporator
fan motor, and to a refrigeration chassis having an
improved structure for directing flow o~ ambient air past
the high side, and to a refrigeration chassis having
structure for cooling an exterior evapurator fan motor, and
to a method of cooling with a U-shaped ambient air flow,
and to a method of cooling an evaporator ~an motor~
THE PRIO~ ART
Glass door re~rigerator coolers are well known to
consumers and retailers alike. These coolers are typically
found in grocery stores, service stations, ~lorist shops,
and similar retailers. The goods sold from these coolers
are mostly beverages and perishables, including soft
drinks, juices, beer, milk, dairy products, ice cubes,
frozen foods, fish bait, fl~wers and the like. These
coolers are uaually placed in a help-yourself location
where the consumer selects and removes his own goods. The
consumer looks through the glass, makes a selection, opens
a door, removes the selected produet and the door must then
be closed by the customer and/or by an automAtic closing
mechanism.
There are sev~ral manufacturers of these coolers,
including the Beverage-Aire Division of Gerlock Industries
of Erie, Pennsylvania, ~rue Manufacturing Company of St.
Louis, Missouri; H.A. Brown Ltd. o~ Markham, Canada;
~apanese entities such as Sanyo, Fuji, Hitachi, Kawasaki;
and several other entities.
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This type of refrigerated cooler has typically
been used inside of a store and the cooler has been
protected from the weather and the elements. These coolers
come wi~h two types of doors, a first door slides laterally
and a second door is hinged on the side and opens outwardly.
The slider door has seal problems because the seals are not
tight and they wear out. The hinged door seals better but
does not always close reliably. Condensate on the doors and
heat loss through unsealed or open doors is a problem.
ModuIar pullout refrigeration is a standard
feature on virtually all of these coolers. The condenser and
evaporator are built up in a single chassis which typically
slides in and out of the cooler frame. There are two
divergent lines of thought on where the refrigeration
chassis should be. The prevalent school of thought places
the refrigeration chassis on the bottom of the cooler and
the second school of thought has the chassis on the top of
the cooler. Each has good and bad points. The bottom cha~ssis
is of lower thermal efficiency because its heat load goes
upward on the cold chamber, there is a loss of the lowest
shelf from the cold chamber, it is more difficult to force
the cold air up in the cold chamber, but it is of lesser
manufacturing cost and the refrigeration chassis is easier
to install and remove and the ~chassis can be serviced and
removed and installed from the front of the cooler.
The top mounted chassis gives a more efficient
cooler because the cooled air tends to draft down and the
heat load goes up and away from the cold chamber. An extra
shelf is available in the bottom of the cold chamber and the
chassis is mounted behind a lighted sign atop the unit which
makes double usage of the height occupied by the sign. The
lighted sign on a top mount chassis cooler is typically
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larger than a bottom chassis cooler. The top mounted chassis
is definitely more difficult to remove, service and install
because it must be lifted up and lowered down, and has been
accessible only from the back of the unit.
However, the top chassis cooler is thought to be
the prefer~able cooler for most of the market applications
~ecause of its volumetric, energy, and merchandising
efficiency advantages.
One of the problems the top chassis cooler has
exhibited is shunting or short cycling of heated and
discharged ambient air in the condenser coil or high side of
the chassis when the cooler has been installed against a
wall and/or under a low ceiling. Either the low ceiling or
wall will adversely affect flow of air into and out of the
condenser of high side, and the chassis will recycle hot air
and the thermal efficiency will decrease a measurable and
significant amount.
These coolers typically have an evaporator fan or
fans inside of the cooler to circulate air through an
evaporator and over the goods on shelves in the cooling
chamber. The predominate practice is to place both the fan
and its electric motor inside of the cooling chamber. The
fan and motor run constantly and the fan motor is cooled by
the flow of cold air within the cooling chamber. The
objectionable part of this is that the waste heat load of
the motor is discharged into the cooling chamber and must be
overcome by extended and/or more frequent running of the
cooling chassis. This is a serious inefficiency. The problem
with putting the fan motor outside the cooling chamber has
been that there is no or insufficient air flow to cool the
fan motor, fan motors burn out, and there have been
significant air leaks where the motor shaft extends through
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the cooler wall and into the cooling chamber.
Typically the evaporator fan pulls a negative
pressure around the shaft because of the centrifugal effect
upon air in the fan blades. The negative pressuredraws air
in and tends to slightly pressurize the inside of the
cooler. While this sounds like a miniscule effect, it is
just enough to keep a hinged door from closing, or ~o force
a leak through the seal of a door. Again there is a further
loss of efficiency and an objectionable characteristic in
the cooler.
Glass door coolers have not been successfully
placed outdoors for several reasons. The bottom chassis
coolers cannot be outside in service stations because of the
arcing of contactors near ground level where fuel fumes
are. Further, bottom chassis coolers plug themselves up with
leaves, paper debris, and tree and plant seeds. The
refrigeration chassis of either top or bottom chassied
coolers have not been effective for outside service and have
been susceptible to the effects of rain, snow, dirt, birds,
rodents and the like.
OBJECTS OF TH_ INVENTION
It is an object of the present invention to
provide a refrigerated cooler having improved and relatively
high efficiency.
It is an object of the present invention to
provide a refrigerated cooler that is suitable for use in an
outdoor environment and which meets the electrical and
safety requirements for outdoor use, and which is relatively
waterproof and reliable in an outdoor environment.
It is an object of the present invention to
provide an improved refrigerated cooler which has improved
efficiency when located against a wall and/or under a low
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ceiling.
It is an object of the present invention to
provide a refrigerated cooler having increased thermal
efficiency and increased reliability and an extended lif~
of its cold air circulation system.
It is an object of the present invenkion to
provide an improved re~rigeration system khat improves khe
reliability of the doors so that the doors stay closed and
do not fog up with condensate, and that has a high thermal
efficiency.
It is an object of the preferred embodiment of
the present invention to provide a refrigerated cooler that
takes the fan motor out of the cold chamber, buk still
cools the fan motor for reliability and long life.
It is an object of the preferred embodiment of
the invention to provide an improved refrigeration chassis
for a cooler, the chassis having an evaporator fan motor
removed ~rom the low side o~ the r~frigeration system while
having fan motor cooling from the low side.
It is an object of the preferred embodiment of
the present invention to provide an improved re~rigeration
chassis for a cooler, the chassis having a high side with
an improved structure for drawing and exhaustin~ ambient
air that enables use of the chassis outside, inside,
against a wall, or under a low ceiling.
It is an object of the preferred embodiment of
the present invention to provide an improved method of
aooling a cooler, having improved drawing and exhausting of
ambient air giving high efficiency and usability oukside,
inside, and against walls or under a low ceiling.
It is an object of the preferred embodiment of
the presen~ invention ko provide an improved method of
cooling a cooler, having decreased heat loads in khe cold
chamber and cooling of the cold ahamber fan motor.
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These and other objects of the :invention will
become manifest to those ver~ed ln the art upon study and
reviewal of the teachinys o~ the di~closure herein.
SUMMARY OF THE INVENTION
According to the principles of one aspect of the
present invention~ a refrigerated cooler with an internal
cold chamber nas a refrigeration chassis on one of the
vertically spaced cabinet ends, a low side with an evapor-
ator and evaporator fan, a high side with a compressor and
a condenser coil, a high side air inlet duct between the
chassis and a first wrap side of the cooler, a high side
outlet duat between the chassis and a second wrap side of
the cooler, an inlet deflector between the ~hassis and the
*irst wrap side, and an outlet air deflector between the
chassis and the second wrap side; the high side air flow is
directed in a U-shape around the low side.
A refrigerated cooler according to a further
aspect of the invention has an insulated cabinet with an
internal cold chamber, a refrigeration chassis having a low
side and a hiqh side an evaporator fan in the low side, a
fan motor outside of the low side, a shaft connecting the
~5 motor to the fan, and a cold air structure between the fan
and the motor for drawing cold air from a pressure zone
behind the fan and directing the cold air upon the fan
motor to cool the motor.
A refrigerator chassis for a cooler preferably
has a high side, a low side, an evaporator fan motor
outside of the low side, a fan motor shaft extending into
the low side to an evaporator fan in the low side, struc-
ture for taking cold air from a pressure zone downstream of
the fan to outside of the low side, and structure for
directing the cold air upon the fan motor.
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A refrigerator chassis ~or a cooler pre~erably
has a high side, a low side, an insulated shell around the
low side, a high side air panel having a central portion
parallel to and spaced from a shell side, an inlet air
deflectox extending ~utward of the central panel and around
toward the shell, and an outlet air deflector extending
outward from an outlet end of the central panel and around
toward the shell; the structure defines a U-shaped passage
Por flow of air through the high side and around three
sides of the low side.
A method of cooling a cooler according to a still
further aspect of the invention, has the steps of chilling
an evaporator, transferring heat from the evaporator to a
condenser, drawing ambient air from the rear of the cooler,
propelling the drawn air transversely through the conden-
ser, and exhausting the heated ambient air to the rear of
the cooler while directing the flow of ambient air in a U-
shape around and spaced from the evaporator.
A method of cooling a cooler according to a yet
still further aspec* of the invention has the steps of
chilling an evaporator, drawing air over the evaporator to
cool the air a~d propelling the air to a work load in a
cold chamber of the cooler, taking some cold air from the
propelled flow and directing it outside of the cold chamber
to an exterior motor Por the evaporator fan, and cooling
the fan motor with the taken and directed cold air.
A method of cooling a cooler preferably has the
steps of chilling an evaporatorl drawing air over the
evaporator and propelling the air with an evaporator fan,
taking some of the cold air to outside of the cold cham-
ber, directing the taken cold air upon an evaporator fa~
motor, and cooling the fan mokor with the cold air as the
motor powers the fan to circulate cooled air within the
cooler.
These and other advantages cf the invention will
become manifest to those versed in the art upon review and
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study of the teachings o~ the pre~rred embodimenk of the
invention hereinafter described.
5BRIEF DESCRIP~ION OF THE DRAWINGS
FIGURE 1 is a perspective view looking downward
at the pr~erre~ embodiment of a refrigerated cooler
according to the present invention;
10FIGURE 2 is a persp~ctive view of the rear side
of tha structure of FIG. l;
FIGURE 3 is a top plan view of the refrigeration
chassis of the structure o~ FIG. 1 with the top cover taken
o~f;
15FIGURE 4 is a sectional elevational view of the
structure of FIG. 3, taken through lines IV-IV;
FIGURE 5 is a sectional detail plan view of the
rear corner of the structure of FIG. 1;
FIGURE 6 is a rear elevational view of the
20structure o~ FIG. 1 with the shroud taken of~;
FIGURE 7 is a plan view of the high side air
panel of the structure of FIG. 3;
FIGURE 8 is an elevational seational view of the
structure of FIG. 3, taken through the centre line of the
25evaporator fan motor, and
FIGURE 9 is an elevational sectional view taken
throu~h lines IX-X of FIG. 8.
DESCRIPTION OF ~E PREFERRED EMBODIMENT
~he refrigerata~le cooler, generally indicated by
the numeral 10 in FIGS. 1 and 2, has a cabinet 11 and a
pair of doors 12 which enclose an internal cooling chamber
13. A plurality of shelves 14 are inside the cooler 10.
35~he shelves 14 are typically a grid of wires enabling air
circulation through the shelves 14, and the cabinet floor
15 is usable as the lowest support for good~ to be sold
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(not ~hown~ such as soft drinks and dairy products~ The
doors 12 are preferably hinged to the cabinet 11 and are
openable from the centre as shown in FIG. 1. Each door 12
has a peripheral structural frame 16 and a transparent
centre 17 preferably of multilayer glass. Each door 12 has
a suitable and conventional airtight gasket 18 which seals
the door 12 to ~he cabinet 11 when ~he door 12 is clo~ed.
~n a~vertising sign 19 which pre~erably is backlighted, is
mounted to the cabinet 11 above the doors 12. On the rear
of the cabinet 11 is a shield 20 which will be explained
further, and on top is a waterproof cover 21 having a
waterproof cooler control cover 22.
~ he refrigeration chassis, generally indicated by
the numeral 25, is best shown in FIGS. 3 and 4, and has a
high side 26 and a low side 27. The high side 26 has a
condenser coil 28, a condenser ~an and motor unit 29, a
refrigeration compressor 30 and the refrigeration control
31. The low side 27 has an evaporator coil 32, a conden-
sate collector and baf~le 33, and a propeller-type evapor-
ator fan 34. The fan 34 is mounted on a motor shaft 35
which in the preferred embodiment shown in the drawings
extends f~om an evaporator fan motor 36 in the high side
26. The evaporator 32, baffle 33 and fan 34 are all in an
air cooling chamber 37 o~ the low side 27, and the chamber
37 is enclosed on its top and all four sides by an insu-
lated wall 38 which is open on its bottom to register with
an air inlet 39 and an air outlet 40 of the cooling chamber
13.
3~
A preferred feature of the present invention
resides in the structure ~or providing air ~low in a U
shaped path through the high side 26. The chassis 25 is
positioned about in the transverse centre of the cooler 10,
is narrower in width than the cooler 10, and is spaced
inward from both of the cooler wrap sides 41, 42. The
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chassis 25 has a front side 43 which is secure~ to and
spaced from the ingulated wall 38 by fore-a~t braces 44O
Between the wall 38 and the front side 43 is a transverse
air flow passageway through the condenser 28 and over the
compressor 30 and the evaporator ~an motor 36.
As shown best in FIG. 3, the space between the
cabinet wrap first side 41 and the first chassis end 45
forms a high side air inlet duct 46 having an inlet 47 flush
with the cabinet backside 48 and the backside 49 of the
chassis 25, and the space between the cabinet wrap second
side 42 and a second chassis end 50 forms a high side
ambient air outlet duct 51 havlng an outlet 52 flush with
the backsides 48, 49. The front of the inlet duct 46 ls
bounded by an inlet air deflector 53 which is concavely
curved as shown and which closes off the space between the
wrap side 41 and the front side 43. The front of the outlet
duct 51 is bounded by an outlet air deflector 54 which is
concavely curved as shown and which closes off the space
between the wrap side 42 and the front side 43.
FIG. 6 best illustrates the structure of the ends
of the deflectors 53, 54. Each deflector 53, 54 has an outer
distal end 55 which is pre-loaded against the inside of a
respective wrap side 41, 42 to give an effective airtight
seal. Each deflector 53, 54 has an ear 56 which i9 fastened
by a screw 57 to a rolled over flange 58 on a respective
wrap side 41, 42. The deflectors 53, 54 and the front side
43 are a common single piece structure formed from the sheet
metal blank shown in FIG. 7: with this construction there
are minimal air leaks and no gaskets to worry about. The
sign 19 is removable and the chassis 25 is accessible and
removable from either the front or back of the cooler 10.
The shield 20 is secured to the cabinet back side
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48 by standoff fasterlers 59 as best shown in FIG. 5. The
shield 20 is over the inlet 47 and outlet 52 and has a
waterproof snow and rain cap 60 above the inlet 47 and
outlet 52. The shield 20 has a rear panel 61 which is spaced
rearward of the cabinet backside 48 and which extends from
the rain cap 60 to well below the inlet 47 and outlet 52~
The rear panel 61 has a set of downward directed louvers 62
to the rear of the inlet 47 and the outlet 52. The louvers
are at least as wide as the inlet 47 and outlet 52. In the
center of the rear panel 61 is a Z-shaped vertical barrier
63 that extends from the rain cap 60 to the bottom of the
rear panel 61. The rear panel 61 has a pair of opposed sides
64 that are each folded over and butted against the cabinet
backside and held by the fasteners 59. The fasteners 59,
folded over sides 64 and barrier 63, all hold the rear panel
61 out so it cannot be collapsed against the backside 48.
The shield 20 forms a vertically directed opening 65 in
between the sides 64. The opening 65 opens downwardly so
that ambient air is both taken in and exhausted generally
downward in divided streams which are separated from each
other by the barrier 63.
The top cover 21 has four flanges 66 that come
down over the sign 19, rain cap 60i and cabinet sides 41, 42
so that rain cannot enter the chassis 25. The waterproof
control cover 22 above the control 31 is selectively open to
give access to the control 31 only from above the cooler 10
so that customers and unauthorized employees do not have
access and cannot easily tamper with the control 31.
pr~err~
1 Another~ impo-E~ant-- feature of this invention is
that the evaporator fan motor 36 is normally cooled by the
structure shown in detail in FLGS. 8 and 9. The fan motor
shaft 35 extends through an opening which forms a cold air
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outlet 70 in the insulate~ wall 38. The cold air outlet 70
is fed by a plenum chamber 71 formed between a metal hat
section 72 securad to a cold wall 73. A gasket 74 seals
the evaporator fan mokor 36, which preferably is an open
frame motor 36, to the cold air ou~let 70. The hat section
72 and the plenum 71 extend generally horizon~ally and
transversely across and in the insulated wall 38 to beyond
the diameter of the avaporator ~an 34 as best shown in FIG.
~. There is a cold air inle~ 7~ in each end of the plenum
71: both cold air inlets are outside of the diameter of the
evaporator fan 34 and in a pressure zone 76 which is
downstream of the evaporator fan 34 and the baffle 33. A
small orifice extends through the insulated wall 38 into
the inlet duct 46 and forms a pressure break inlet 77 just
upstream of the evaporator coil 32. An air sPal 78 is
mounted over the shaft 35. The air seal 73 preferably
comprises a layer of double backed adhesive coated foam and
a washer of thin aluminum. The air seal 78 is adhesively
secured on the wall 73 only after the motor 36 has been
~0 fastened in place and the seal 7~ has almost a zero clear~
ance on the shaft 35. The cold air outlet 70 and seal 78
are co-axial with and about the shaft 35 and the fan 34 i~
placed on the shaft 35 aPter the seal 78 has been secured.
The plenum 71 forms an air conduit from each of the cold
air inlets 75 to the cold air outlet 70.
In the operation of the cooler 10 and in the
practice of the preferred methods of the present invention,
the evaporator 32 is chilled and cabinet air i~ drawn from
the cooling chamber 13 and through the evaporator 32. The
cooled cabinet air is then propelled by the fan 34 against
the wall 73 and then through the cabinet inlet 40 and
through the cooling chamber 13 wherein a workload of
product is cooled. ~ownstream of the fan 34 and on the
wall 73, there is a low pressure zone ...
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around the shaft 35 and a high pressure zone at and beyond
the outer diameter of the fan 34. The fan motor cold air
inlets 75 are both in the high pressure zone. soth the low
and high pressure zones are primarily a con.sequence of the
centrifugal force of the air being rotated by the fan blade
34. This centrifugal force is of a significant magnitude.
The high pressure forces just cooled cold air through -the
inlet 75 and into the plenum 71 and through the outlet 70
and around the motor shaft 35 and through the motor 70 where
the cold air goes directly over the motor windings. This
cooling air flow occurs at all times when the fan motor 36
is on. The air seal 78 prevents suction of air back into the
cabinet past the motor shaft 35. The pressure break inlet
successfully serves two functions. The coollng air that
propelled out through the motor 36 has to come from
somewhere; it comes from the pressure break inlet 77. This
break inlet 77 is the throttle that restrictively controls
how much air can be propelled out through the motor 36 and
the break inlet 77 is sized to control the air flow. The
break inlet 77 also prevents the fan 34 and motor cooling
system from pulling an excessive partial vacuum in the
cooling chamber 13. If an excessive partial vacuum is in the
cooling chamber 13, it takes a tremendous pull to open the
se~aled front doors 12 because each door has an area of about
ten to fifteen square feet. However, a slight vacuum is
maintained in the cabinet 11 to keep the doors 12 closed.
This break inlet 77 is smaller and has a lesser air flow
than the cooling air path including the inlets 75, plenum
71, outlet 70 and the pathway through the motor 36. The fan
motor 36 and the fan 34 are run continuously and they do not
transfer waste heat into the cooling chamber 13: a small
amount of the cold air is drawn from the cooling chamber 13
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to keep the motor 36 cooled regardlegs of whether or not the
condenser fan 24 is blowing air over the exterior of the
frame of the evaporator fan motor 36.
The high side 26 i5 operative when the low side 27
is cooling and the compressor 30 and condenser fan 29 are
running. Ambient air is drawn upward through the inlet
louvers 62 and upward inside the shield 20. The ambient air
is then drawn forward in the inlet duct 46 and is directed
around the corner by the inlet air deflector 53 and through
the condenser coil 28 and over the evaporator fan motor 36
and the compressor 30. The ambient air which now has the
heat from the condenser coil 28, is then directed around the
corner by the outlet air deflector 54 and then rearward
through the outlet duct 51 and then downward and out of the
outlet louvers 62 and downward and out of the shield 20. The
louvers 62 and the barrier 63 keep the inlet flow of ambient
air clean of leaves and grass and paper and ground dirt and
debris, and keep the ambient inlet flow and heated exhaust
flow separate from each other and directed away from the
customer and the doors 12 regardless of whether the cooler
10 is under a short ceiling or against a wall. The air taken
in is not heated by sunlight beyond normal, and the cooler
10 stays neat and clean and is silent. The controls 31 are
top mounted where they will not come in contact with
explosive or corrosive fumes at ground level. The cooler 10
protects itself well from rain,~ sleet, snow, winds,
sunlight, leaves, seeds of trees and other plants, and
ground debris. The high side 26, low side 27 and controls 31
are all relatively inaccessible to the public and the cooler
10 is quite tamperproof.
This new and improved cooler 10 enables the
placement of glass door coolers inside, outsidel in service
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stations, in unattended places, under low ceilings, against
wall and enables new methods of merchandising and energy
conser~ation to be considered.
~ lthough various minor modifications may be
suggested by tnose versed and experienced in the art, be it
understood that I wish to embody within the scope of the
patent warranted hereon all such embodiments as reasonably
and properly come within the scope of my contribution to the
art.
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