U.S. patent number RE40,123 [Application Number 10/339,862] was granted by the patent office on 2008-03-04 for removal of heat and water vapor from commercial dishwashing machines.
This patent grant is currently assigned to Ecolab Inc.. Invention is credited to Kent R. Brittain, Glen W. Davidson, Scott A. Johansen, Lee J. Monsrud.
United States Patent |
RE40,123 |
Johansen , et al. |
March 4, 2008 |
Removal of heat and water vapor from commercial dishwashing
machines
Abstract
A water-driven jet or venturi extraction means is used to
remove, capture and cool the hot, highly humid air created within
commercial dishwashers during a wash rinse or sanitization cycle. A
cold water spray is used to create a pressure reduction zone which
serves to draw in hot, highly humid air from the dishwasher. Water
vapor cools and condenses on contact with the cold water spray
within the venturi. The invention also serves to help vent the
dishwasher. Cool, fresh air is drawn into the dishwasher while the
hot air is drawn into the venturi.
Inventors: |
Johansen; Scott A.
(Minneapolis, MN), Brittain; Kent R. (Ellsworth, WI),
Monsrud; Lee J. (Inver Grove, MN), Davidson; Glen W.
(Roseville, MN) |
Assignee: |
Ecolab Inc. (St. Paul,
MN)
|
Family
ID: |
22352889 |
Appl.
No.: |
10/339,862 |
Filed: |
January 9, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
09114015 |
Jul 10, 1998 |
06170166 |
Jan 9, 2001 |
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|
Current U.S.
Class: |
34/62; 34/595;
34/68; 34/69; 34/79; 34/84 |
Current CPC
Class: |
A47L
15/48 (20130101) |
Current International
Class: |
F26B
19/00 (20060101) |
Field of
Search: |
;34/337,340,343,372,381,403,417,469,430,60,61,62,68,69,76,79,84,26,130,595,596
;68/5C,5D,5E,19,20 ;239/290,597,601 ;62/304,259.4,314 ;134/56D |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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391 216 |
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128108 |
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3345603 |
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DE |
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3513639 |
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DE |
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3515592 |
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DE |
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3538305 |
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195 22 307 |
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0000192 |
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EP |
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0 486 828 |
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0 521 815 |
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EP |
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0 721 762 |
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EP |
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EP |
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EP |
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0 800 786 |
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EP |
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0 970 654 |
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Jan 2000 |
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EP |
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2337536 |
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Sep 1977 |
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2491322 |
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Apr 1982 |
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FR |
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1245570 |
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Sep 1971 |
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GB |
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0 813 1391 |
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JP |
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0 822 4201 |
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Sep 1996 |
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JP |
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1655460 |
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Jun 1991 |
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SU |
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Primary Examiner: Gravini; Stephen
Attorney, Agent or Firm: Kagan Binder, PLLC
Claims
We claim:
1. A dishwashing machine that can be cooled after completing one or
more cycles, said machine using water of elevated temperature, said
machine producing a hot humid atmosphere, the machine comprising:
(i) a machine enclosure comprising at least one inlet in fluid
communication between the machine interior and the machine
exterior, and (ii) extraction means comprising a housing comprising
a water jet with a spray nozzle, and at least one conduit in fluid
communication between the machine enclosure interior and the
housing, the spray nozzle providing a water spray effective to
create a zone of reduced pressure within the housing for removing
the hot humid atmosphere from within the machine enclosure through
the conduit, while causing entry of fresh air into the machine
through the inlet.
2. The dishwasher of claim 1 wherein the water jet comprises a
source of water between about 35.degree. F. and 100.degree. F. and
between about 10 and 60 psi.
3. The dishwasher of claim 2 wherein the water jet comprises a
source of water between about 35.degree. F. and 70.degree. F. and
between about 30 and 60 psi.
4. The dishwasher of claim .[.3.]. .Iadd.1 .Iaddend.wherein the
water jet comprises a spray nozzle with a spray angle of about
30.degree. and a flow rate of about 3 gallons per minute at a
supply pressure of about 40 .[.psi.]. .Iadd.p.s.i.Iaddend..
5. The dishwasher of claim 1 wherein the housing comprises a 1 to 3
inch ID pipe, the conduit comprises a 1 to 3 inch ID pipe, the
housing ending in a discharge section comprising a 1 to 4 inch ID
pipe.
6. The .[.method.]. .Iadd.dishwasher .Iaddend.of claim 1 wherein
the extraction means .[.operates.]. .Iadd.is configured to operate
.Iaddend.for a duration of 10 to 30 seconds at the end of a final
rinse period.
7. The .[.method.]. .Iadd.dishwasher .Iaddend.of claim 1 wherein
the extraction means .[.operates.]. .Iadd.is configured to operate
.Iaddend.intermittently.
8. The .[.method.]. .Iadd.dishwasher .Iaddend.of claim 1 wherein
the water jet has a spray angle of at least 15.degree. F.
9. The .[.method.]. .Iadd.dishwasher .Iaddend.of claim 8 wherein
the water jet contacts the side walls of the discharge pipe.
10. The .[.method.]. .Iadd.dishwasher .Iaddend.of claim 8 wherein
the water jet has a spray angle of between about 15.degree. and
50.degree. F.
11. The .[.method.]. .Iadd.dishwasher .Iaddend.of claim 8 wherein
the water jet has a flow rate of between about 0.5 and 10 gallons
per minute and a supply pressure of between about 10 and 60
p.s.i.
.Iadd.12. A dishwashing machine, comprising: an air inlet defined
in the dishwashing machine providing fluid communication between a
dishwashing machine interior and a dishwashing machine exterior;
and a vent in fluid communication with the dishwashing machine
interior, the vent comprising a conduit and a spray nozzle
constructed and arranged to direct a spray of fluid through the
conduit section and create a zone of reduced pressure within the
vent so that air and moisture within the dishwashing machine
interior is drawn into the vent and ambient air from the
dishwashing machine exterior is drawn through the air
inlet..Iaddend.
.Iadd.13. The dishwashing machine of claim 12 wherein the conduit
is a vertical conduit..Iaddend.
.Iadd.14. The dishwashing machine of claim 13 wherein spray nozzle
is located in a top portion of the vertical conduit..Iaddend.
.Iadd.15. The dishwashing machine of claim 12 wherein the air inlet
is a gap adjacent to a door of the dishwashing
machine..Iaddend.
.Iadd.16. The dishwashing machine of claim 12 wherein the vent is
configured to operate the spray nozzle intermittently..Iaddend.
.Iadd.17. The dishwashing machine of claim 12 wherein the spray
nozzle is configured so that the spray of fluid contacts a wall of
the conduit..Iaddend.
.Iadd.18. The dishwashing machine of claim 12 wherein the spray
nozzle is configured to direct the spray of fluid to have a spray
angle of at least 15 degrees..Iaddend.
.Iadd.19. The dishwashing machine of claim 18 wherein the spray
angle is between about 15 degrees and 50 degrees..Iaddend.
.Iadd.20. The dishwashing machine of claim 12 wherein the conduit
directs fluid from the spray nozzle to a drain outside of the
dishwashing machine interior..Iaddend.
.Iadd.21. The dishwashing machine of claim 12 wherein the vent is
configured to remove gas or vapor from the dishwashing machine
interior at a rate of at least about 20 cubic feet per
minute..Iaddend.
.Iadd.22. The dishwashing machine of claim 12 wherein the vent is
configured to reduce the temperature within the dishwashing machine
interior by at least about 20 degree F. within about two minutes of
operation..Iaddend.
.Iadd.23. The dishwashing machine of claim 12 wherein the vent is
configured to reduce the humidity within the dishwashing machine
interior from substantially saturated to a humidity approximating
the humidity in the dishwashing machine exterior within about a
half minute of operation..Iaddend.
.Iadd.24. The dishwashing machine of claim 12 wherein the zone of
reduced pressure comprises a pressure difference from an ambient
pressure at the dishwashing machine exterior of at least about 2
inches of water..Iaddend.
.Iadd.25. The dishwashing machine of claim 12 wherein the spray
nozzle is in fluid communication with a source of fluid at a
temperature of between about 35 degree F. and 100 degree
F..Iaddend.
.Iadd.26. The dishwashing machine of claim 12 wherein the spray
nozzle is in fluid communication with a source of fluid at a
temperature of between about 35 degree F. and 70 degree
F..Iaddend.
.Iadd.27. The dishwashing machine of claim 12 wherein the spray
nozzle is in fluid communication with a source of fluid with a
pressure of about 10 to 60 p.s.i..Iaddend.
.Iadd.28. The dishwashing machine of claim 27 wherein the spray
nozzle is configured to discharge fluid at a flow rate between
about 0.5 and 10 gallons per minute..Iaddend.
.Iadd.29. The dishwashing machine of claim 12 wherein the spray
nozzle is in fluid communication with a source of fluid with a
pressure of about 30 to 60 p.s.i..Iaddend.
.Iadd.30. The dishwashing machine of claim 12 wherein the conduit
comprises a first pipe section having an inner diameter of about 1
to 3 inches and a second pipe section having an inner diameter of
about 1 to 4 inches..Iaddend.
.Iadd.31. The dishwashing machine of claim 12 wherein the vent is
confirmed to operate the spray nozzle for a duration of about 10 to
30 seconds at the end of a final rinse period..Iaddend.
.Iadd.32. A dishwashing machine, comprising: an air inlet defined
in the dishwashing machine providing fluid communication between a
dishwashing machine interior and a dishwashing machine exterior;
and a vent in fluid communication with the dishwashing machine
interior, the vent comprising a conduit and a spray nozzle
constructed and arranged to direct a spray of fluid to create a
zone of reduced pressure within the vent so that air and moisture
within the dishwashing machine interior is drawn into the vent and
ambient air from the dishwashing machine exterior is drawn through
the air inlet..Iaddend.
.Iadd.33. The dishwashing machine of claim 32 wherein the spray
nozzle is positioned within the conduit and directs a spray of
fluid through the conduit..Iaddend.
.Iadd.34. A dishwashing machine, comprising: an air inlet defined
in the dishwashing machine providing fluid communication between a
dishwashing machine interior and a dishwashing machine exterior;
and a vent in fluid communication with an interior of the
dishwashing machine, the vent comprising a conduit and a spray
nozzle constructed and arranged to direct a spray of fluid through
the conduit section and create a zone of reduced pressure within
the vent so that air and moisture within the dishwashing machine
interior is drawn into the vent and ambient air from the
dishwashing machine exterior is drawn through the air inlet,
wherein the conduit directs fluid from the spray nozzle to a drain
outside of the dishwashing machine interior..Iaddend.
Description
FIELD OF THE INVENTION
The invention relates to a method and apparatus for venting
gaseous, vaporous and airborne particulate material from, and
cooling the inside, of processing equipment or machinery. In
particular, the invention relates to the removal of heated air
laden with water vapor from within commercial warewashing or
dishwashing machines.
BACKGROUND OF THE INVENTION
Commercial automated dishwashers have been used for many years in a
variety of different locales, wherever large amounts of cookware,
silverware, dishware, glasses or other ware need to be cleaned and
sanitized. Regardless of whether the dishwasher in question is a
simple batch loading dishwasher or a complex multi-stage machine,
there is an on-going problem with heated water vapor escaping the
machine at the end of a cleaning program. This heat and humidity
comes into direct contact with the kitchen personnel and generally
reduces comfort of the kitchen environment. Commercial dishwashing
machines can heat water or utilize very hot water from other
sources, especially in the final rinse stage, to help ensure
cleaning and sanitation. Current dishwashers are classified as
either high temperature machines or as low temperature machines,
based on final rinse water temperatures. The high temperature
machines have a final rinse water temperature of at least about
180.degree. F. while the low temperature machines have a final
rinse water temperature of about 160.degree. F. Such high
temperatures are necessary to ensure adequate sanitization of the
dishes or other ware being cleaned. The high temperature rinse
allows for one-step sanitization whereas the low temperature rinse
is typically accompanied by an additional chemical (chlorine,
peracid, etc.) sanitization addition step. In either situation, hot
ware and significant volumes of heated, highly humidified air are
created in the dishwasher, particularly as a result of the final
rinse, which is typically the hottest step in the dish or
warewashing process.
Direct contact with hot, humid air can pose safety problems. The
humidity causes significant safely problems for people who wear
glasses and/or contact lenses. The hot, humid air can irritate
people without eyewear as well. Significant amounts of heated water
vapor are put into the room environment, straining air conditioning
systems and generally creating discomfort for operators. Further,
the dishes removed from the dishwasher can be at high
temperature.
One way to address these difficulties concerns the use of vent
hoods to capture the hot, highly humid air escaping from the
dishwasher upon opening. A drawback to this method is that the hot,
highly humid air contacts environmental air in the use locus and
the hood removes only a portion. As a result, some heat and
humidity is transferred to the immediate environment. While the
hood will draw the hot, highly humid air up and away from the
dishwasher, it may fail to completely protect the operator from
contact with heat and humidity. In addition, hoods are large, noisy
and expensive, wasting heat during winter months, and conditioned
air in summer months. Further, such a system requires venting to
the exterior of the building. Another way to address these problems
concerns the use of electric exhaust fans to remove the heat and
water vapor. Unfortunately, this is noisy, requires electricity and
means to vent to the exterior of the building. In addition, this
also requires a separate means to cool and condense the water
vapor. EP 0 753 282 A1 deals with the problem of hot water vapor by
cooling and condensing the steam released from the dishwasher. This
is accomplished by directing the steam through a heat exchanger
through which cold water is circulated. However, this device is
limited to applications in which the wash chamber is sealed. Such a
device would not work, for example, in a single-stage or
multi-stage dishwashing machine open to the atmosphere. EP 0 721
762 A1 teaches the use of a fan to pull the steam into a
condensation chamber in order to prevent the escape of moisture to
the immediate environment. Of course, this method requires the use
of a fan, which adds expense, complexity and noise to the
dishwashing apparatus.
Therefore, a need remains for a simple, inexpensive and unobtrusive
means for capturing the water vapor released from commercial
dishwashers.
SUMMARY OF THE INVENTION
In brief, the invention involves the use of a water spray to create
a zone of reduced pressure that can be used to remove heat and
humidity and vent the interior of machines such as commercial
dishwashers. Preferably, a water spray is used to form a zone of
reduced pressure that draws the heat and humidity into the zone. In
the zone the heat and humidity is captured and cooled. The hot,
highly humid air created within commercial dishwashers can be
removed rapidly and the ware can be cooled with ambient air. A cold
water spray is used to create a pressure reduction which serves to
draw in hot, highly humid air from the dishwasher. The high
temperature water vapor cools and condenses on contact with the
cold water jet or spray. The invention also serves to help vent the
dishwasher and cool ware, as cold, fresh air is drawn into the
dishwasher to replace the hot air drawn into the zone of reduced
pressure.
Accordingly, the invention is found in a method of removing a
heated atmosphere from a machine enclosure, the method comprising
energizing a flow of water from a water spray within a housing to
create a zone of reduced pressure in the housing in fluid
communication between the machine interior and the housing, the
reduced pressure introducing fresh atmosphere into the machine
while removing the heated atmosphere.
Finally, the invention can also be found in a dishwashing machine,
using water of elevated temperature, that can be cooled after
completing one or more cycles, the machine comprising a machine
enclosure comprising at least one inlet in fluid communication
between the machine interior and the machine exterior, and
extraction means comprising a housing comprising a water jet and at
least one conduit in fluid communication between the machine
enclosure interior and the housing, the spray nozzle providing a
water spray effective to create a zone of reduced pressure within
the housing for removing the hot humid atmosphere from within the
machine enclosure while causing entry of fresh air into the machine
through the inlet.
The extraction means comprises one or more air inlet means in fluid
communication with both the inner compartment of the dishwasher and
with a vertical structure comprising a cold water inlet in fluid
communication with a spray nozzle. The spray nozzle is located at a
horizontal level approximately equal to that of the air inlet
means. The spray nozzle provides a high speed water spray suitable
to create a venturi effect or a zone of reduced pressure that can
serve to pull hot, moisture-laden air through the air inlet means;
and an outlet means. For the purpose of this patent application,
the term "extraction means" refers to a device that can use a
difference in pressure to use the ambient atmospheric pressure to
drive the atmosphere within a machine into the area of reduced
pressure. The term "nozzle spray angle" connotes the angle, within
the spray, bound by the perimeter of the spray as it exits from the
nozzle opening. Such angles can typically range from about
5.degree. up to about 180.degree..
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a perspective view of a typical batch loading commercial
dishwasher showing the apparatus of the invention.
FIG. 2 is a cutaway view of a portion of FIG. 1 which demonstrates
the relationships between the air inlet means, water inlet means
and air outlet means.
DETAILED DESCRIPTION
The invention generally involves the use of a water spray to create
a zone of reduced pressure in fluid communication with the interior
of a warewashing machine. The reduced pressure in the zone can draw
or vent a heated atmosphere comprising heat and humidity from the
interior of machines such as commercial dishwashers. Preferably, a
water spray is used to capture and cool the hot, highly humid air
created within commercial dishwashers. A cold water spray is used
to create a pressure reduction which serves to draw in hot, highly
humid air from the dishwasher. Water vapor cools and condenses on
contact with the cold water spray within the jet or venturi. The
invention also serves to help vent the dishwasher, as cold, fresh
air is drawn into the dishwasher as the hot air is drawn out of the
dishwasher.
The cold water used to provide the venturi effect is service water
from municipal water utilities or wells comprising domestic cold
water at or below ambient room temperature. While an operating
water temperature range of about 35.degree. F. to about 100.degree.
F. is permissible, a range of about 35.degree. F. to about
70.degree. F. is preferred. Obviously, colder water will result in
more efficient vapor condensation. While no specific use of the
discharge water is required, it is envisioned that it could be used
to replenish at least a portion of the wash water needed for
subsequent cycles. Alternatively, the discharge water can be sent
directly to a drain or sump. As the hot, moisture laden air is
drawn out of the machine, cool fresh air is drawn in to replace it.
In a simple single stage, batch loading machine, the gaps around
the side doors can provide the necessary fresh air. At optimal
performance settings, it may be necessary to provide additional air
vents. Larger multi-stage machines may also require additional
venting in order to provide sufficient cool, fresh air.
The venting venturi does not need to operate continuously. In a
batch machine, the operation needs at a minimum to operate for a
sufficient time to vent the machine before opening. Generally, it
would operate for a period of about 10 to about 60 seconds,
preferably about 10 to about 30 seconds during or immediately after
the final rinse step but before opening. The venting venturi could
optionally operate intermittently as needed to help control air
temperature within the dishwasher. In a continuous machine, the
system can operate continuously or the system is operated at the
end of a stage when heat and humidity are at a maximum.
Dishwashing Machines
A wide variety of dishwashing and warewashing machines can utilize
the venting apparatus of the claimed invention. While the figures
show a simple batch-loading dishwasher such as the Hobart AM-14, it
is envisioned that the venting apparatus of the invention could
also be used with larger, multi-stage machines such as the Hobart
FLT.
Performance and Equipment Parameters
A preferred embodiment is seen in FIG. 2, which shows a venting
apparatus attached to a single-stage, batch-loading high
temperature dishwashing machine. While a variety of pipe sizes can
be used, it has been found that optimal, performance exists when
the vertical pipe section has a 2-inch inner diameter (ID) and the
discharge pipe has a 3-inch ID The air inlet pipes also are
optimally 2-inch ID.
A wide range of spray nozzles could be used in the invention. A
wide range of both nozzle angles and flow rates can be used. It has
been discovered that nozzles can be used which have nozzle angles
ranging from 15.degree. to 50.degree., but which are preferably
about 30.degree.. In any event, the nozzle angle used must be
sufficient to permit the water spray to contact the sides of the
discharge pipe. Further, the invention can make use of flow rates
ranging from about 0.5 to about 10 gallons per minute, preferably
about 3 gallons per minute. The water supply pressure can range
from about 10 to about 60 pounds per square inch gauge pressure
(psig), preferably from about 30 to about 60 psig and more
preferably is about 30 psig. It has been found, however, that
optimal performance can be obtained using a nozzle with about a
30.degree. spray angle which delivers about 3 gallons per minute at
a supply pressure of about 40 psig. This particular nozzle delivers
a full-cone spray. The resulting zone of reduced pressure comprises
a pressure difference from the ambient pressure of at least about 2
inches of water. The performance parameters of the invention do
involve tradeoffs, however. In general it has been found that
higher water pressure moves more air, condenses more vapor and is
more efficient. However, it has also been found that larger
capacity nozzles were able to move more air and condense more
vapor. Increasing the capacity of the nozzle drops the water
pressure; hence, the tradeoff.
Depending on the supply water temperature, it has been found that
the vapor extraction capacity can actually surpass the vapor
condensation capacity. The vapor extraction capacity is defined as
the amount of water vapor removed from the dishwasher while the
vapor condensation capacity is defined as the amount of water vapor
actually condensed into a liquid. The vapor extraction efficiency
is defined as the volume of air/vapor moved per gallon of water
used. The apparatus can possibly extract more hot moisture-laden
air than can be condensed. If it is desired to remove all water
vapor from the exiting air, it may be necessary to limit the vapor
extraction efficiency. In general it was found that the draft
created by the water flow was more than sufficient in venting the
machine. In fact, it was found that additional vent holes in the
dishwashing machine were needed to allow for optimal air flow.
The operation of the method and apparatus of the invention can
result in the evacuation of at least about 25 cubic feet of gas or
vapor per minute from the interior of the warewashing machine,
preferably about 20 to 30 cubic feet can be removed per minute of
operation during the practice of the invention. Inside the machine,
the temperature of the ware can be reduced from a temperature of
greater than about 140 to 170.degree. F., or more, to less than
about 120.degree. F. Similarly, the temperature of the enclosed
environment within the machine can be reduced from about greater
than 140 to 170.degree. F. or more, to less than 120.degree. F.
within about 2 minutes during the operation of the machine. The
humidity within the operating environment of the interior of the
machine can be reduced from a substantially saturated atmosphere
(with water vapor) to a humidity approximating the ambient
atmosphere within about 1/2minute of operation of the extraction
apparatus and process of the invention.
DETAILED DESCRIPTION OF THE FIGURES
FIG. 1 shows generally a dishwasher 100 typical of the invention.
The particular machine pictured is a batch-fill high temperature
dishwasher with an enclosing panel 110 and side doors 120 and 120a.
Mounted to a machine panel 110 is the venting apparatus 190.
Visible portions of the venting apparatus 190 include a water inlet
means 150, machine vents or heat and humidity conduits 160,
vertical pipe section 170 and a discharge pipe 180. Also seen in
this figure are cool air inlets 130 which correspond to gaps
permitting fluid communication into the machine around the side
doors 120. Not shown in this figure are optional venting ports
which may be needed, depending on the operational parameters of the
dishwasher. Operation of the venting apparatus 190 to remove heat
and humidity 140 into a combined stream 145 is better explained
using FIG. 2.
FIG. 2 shows a cutaway view 200 generally of the venting apparatus
190. Starting at the top of the figure, a water inlet means 150 is
seen, which provides a source of cold water to the spray nozzle
210. The spray nozzle 210 is housed within the vertical pipe
section 170, which is in fluid communication with the vents or
humidity conduits 160 which in turn are in fluid communication with
the internal compartment of the dishwasher 100 (not seen in this
figure).
Cold water is supplied to the spray nozzle 210 via water inlet
means 150. The high speed spray creates a pressure drop within the
vertical pipe section 170, which serves to draw hot, moisture-laden
air out of the dishwasher 100 and through the hot air inlets 160 to
the vertical pipe section 170. Contact with the cold water spray
helps cool and condense the hot water vapor 140, which then exits
the venting apparatus 190 through the discharge pipe 180 in a
stream 145 comprising service water and condensed humidity. The
combined water and condensed vapor can be sent either to a drain
sump or to the wash tank (neither seen in this figure).
This figure is intended to display the general idea of the
invention and is not meant to define the exact relationship between
the spray nozzle 210 and the vent conduits 160. It has been
discovered that the spatial relationship between these structures
affects the efficiency of the apparatus.
Also seen in FIG. 2 is a transition zone 220, which serves to
provide a smooth transition between the vertical pipe section 170
and the larger diameter discharge pipe 180. More importantly, the
transition zone 220 and increased diameter discharge pipe 180 serve
to control fluid expansion, which increases air flow.
Optimal Pipe Size
While pipe sizes ranging from 1.5 inch ID to 3.0 inch ID were
examined, it was found that 2.0 inch ID pipe outperformed both 1.5
and 3.0 inch ID pipes. Optimal performance was found with a
combination of a 2.0 inch ID pipe used with a transition to a 3.0
inch ID pipe.
Optimal Spray Nozzle Parameters
Nozzles were examined having spray angles ranging from 15 degrees
to 50 degrees. It was discovered that the 30 degree spray angle
nozzle had a higher vapor extraction capacity than either of the
other nozzles tested.
The nozzles were tested at flow rates ranging from 0.7 to 3.5
gallons per minute. Optimal results were discovered using a flow
rate of about 3 gallons per minute at a supply pressure of 40
psig.
The optimal position of the nozzle was observed to be such that the
outer most portion of the water spray contacts the inside of the
pipe wall just past the air inlet pipe.
The above specification, examples and data provide a complete
description of the manufacture and use of the apparatus of the
invention. Since many embodiments of the invention can be made
without departing from the spirit and scope of the invention, the
invention resides in the claims hereinafter appended.
* * * * *