U.S. patent application number 10/454028 was filed with the patent office on 2003-10-16 for exhaust system for electronic equipment enclosure.
Invention is credited to Cosley, Michael R., Lockhart, Julius C..
Application Number | 20030192675 10/454028 |
Document ID | / |
Family ID | 27613668 |
Filed Date | 2003-10-16 |
United States Patent
Application |
20030192675 |
Kind Code |
A1 |
Cosley, Michael R. ; et
al. |
October 16, 2003 |
Exhaust system for electronic equipment enclosure
Abstract
An electronic equipment cabinet where a top cover is made of
upper and lower synthetic resin panels which are welded at their
edges to form an air chamber therebetween. The upper panel is domed
while the lower panel has a corrugated like structure. Access ports
are provided which may be sealed shut. Rain directing berms are
also provided to direct rain to the corners of the cover and away
from access doors to a sealed electronic equipment chamber in the
cabinet. Lateral air and water exhaust passageways extending the
width of the cover is provided as a path for exhaust air from a
heat exchanger which normally moves in one direction but which
under high wind conditions may move in the opposite direction and
for allowing the passage of rain water from one side of the cabinet
to the opposite side.
Inventors: |
Cosley, Michael R.; (Crystal
Lake, IL) ; Lockhart, Julius C.; (Chicago,
IL) |
Correspondence
Address: |
JONES DAY
77 WEST WACKER
CHICAGO
IL
60601-1692
US
|
Family ID: |
27613668 |
Appl. No.: |
10/454028 |
Filed: |
June 4, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10454028 |
Jun 4, 2003 |
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09548043 |
Apr 12, 2000 |
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6598668 |
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Current U.S.
Class: |
165/104.32 ;
165/170 |
Current CPC
Class: |
H05K 7/206 20130101 |
Class at
Publication: |
165/104.32 ;
165/170 |
International
Class: |
F28D 015/00; F28F
003/14 |
Claims
1. An exhaust system for an electrical equipment enclosure, the
enclosure having a heat exchanger mounted therein, said exhaust
system comprising in combination: first and second synthetic resin
panels mounted on top of said enclosure, said panels having an
enclosed space formed therebetween; a centrifugal fan mounted
within said enclosure and in operative communication with said heat
exchanger and said resin panels; said resin panels forming a fan
casing for said centrifugal fan and a first passageway smoothly
transitioning from said centrifugal fan location and extending in a
first direction, said first passageway for exhausting air passing
through said heat exchanger; and said resin panels also forming a
second passageway in communication with said first passageway, said
second passageway extending in a second direction opposite to said
first direction for exhausting air exiting from said centrifugal
fan when pressure in said first passageway is higher than fan
capacity and for allowing water entering one of said first or said
second passageways to flow through to the other of said first or
said second passageways.
2. The exhaust system as claimed in claim 1 wherein: said first and
said second panels form a periphery where said first and said
second panels are separated; and interior of said periphery, said
first and said second panels are adjacent in some locations and
separated in other locations.
3. The exhaust system as claimed in claim 2 wherein: said second
panel includes walls that are generally vertically disposed where
said first and said second panels transition between adjacent and
separated locations.
4. The exhaust system as claimed in claim 3 wherein: various
geometric patterns are formed by said second panel by transitions
between being adjacent and being separated from said first
panel.
5. The exhaust system as claimed in claim 1 wherein: said first and
said second panels are adjacent one another where said panels form
said fan casing and said first and said second passageways.
6. The exhaust system as claimed in claim 5 wherein: said second
panel includes a corrugated cross-section.
7. The exhaust system as claimed in claim 1 wherein: said first
panel includes a length and a width and a bowed shape across said
width.
8. The exhaust system as claimed in claim 1 wherein: said first
panel includes a length and a width and berms extending along said
length and said width.
9. The exhaust system as claimed in claim 4 wherein: said first and
said second panels are adjacent one another where said panels form
said fan casing and said first and said second passageways.
10. The exhaust system as claimed in claim 9 wherein: said second
panel includes a corrugated cross-section.
11. The exhaust system as claimed in claim 10 wherein: said first
panel includes a length and a width and a bowed shape across said
width.
12. The exhaust system as claimed in claim 11 wherein: said first
panel includes a length and a width and berms extending along said
length and said width.
13. A top cover for an electrical equipment enclosure comprising: a
first synthetic resin panel having a periphery; and a second
synthetic resin panel having a periphery, said panels being
separated from one another at said periphery thereof and being
adjacent one another interior of said peripheries.
14. The top cover as claimed in claim 13 wherein: said second panel
includes walls that are generally vertically disposed where said
first and said second panels transition between adjacent and
separated locations.
15. The top cover as claimed in claim 14 wherein: said second panel
includes a corrugated cross-section. (Change claims 6 and 10 from
profile to cross section. Joe, I did this.)
16. The top cover as claimed in claim 15 wherein: said first panel
includes a length and a width and a bowed shape across said
width.
17. The top cover as claimed in claim 16 wherein: said first panel
includes a length and a width and berms extending along said length
and said width.
18. The top cover as claimed in claim 17 wherein: said first and
said second panels form a fan casing and a passageway; and said
first and said second panels are adjacent to one another at said
fan casing and said passageway.
Description
[0001] This is a divisional patent application of copending patent
application Ser. No. 09/548,043, filed Apr. 12, 2000.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an exhaust system for
electrical equipment enclosures and, more particularly, to a top
cover for electronic equipment enclosures which provide better
thermal insulation and noise abatement as well as other
benefits.
[0004] 2. Description of the Related Art
[0005] Some types of electronic or related equipment are typically
located out of doors. Examples are telecommunications equipment and
cable television or data equipment. Often this class of equipment
is referred to as "outside plant equipment" and/or "remote
terminals." Also, it is well know that this equipment generates
excessive heat and undesirable gas. Further, this outside plant
equipment may be located just about any place on the planet, in
very warm, cold, wet, dry, and high wind climates and at high and
low altitudes.
[0006] Over the last several years specialized enclosures or
cabinets have been engineered to form a protective environment for
the outside plant equipment. Presently, such electronic equipment
enclosures or cabinets are constructed with all metal outer panels,
a weather sealed chamber for some of the equipment and non-sealed
chambers for other portions of the equipment. The metal panels,
however, have relatively poor thermal insulation qualities and
noise abatement characteristics. When steps are taken to alleviate
these problems, costs of manufacture and assembly increase
prohibitively. Even without these steps, steel or aluminum panels
are expensive and unnecessarily heavy.
[0007] The general design of the metal cabinets, and especially
heat exchange units located within the cabinets for cooling the
heat generated by the equipment, may be appreciated by reference to
U.S. Pat. Nos. 5,832,988 and 5,570,740. The climatic and human
problems faced by the industry and vendor requirements generated to
protect this outside plant equipment are explained in those
patents. Important steps have been take to alleviate some problems
but problems remain nevertheless.
BRIEF SUMMARY OF THE INVENTION
[0008] The present invention improves upon the metal covers now
being used for equipment cabinets and a number of advantages are
achieved by the improvement. What is described here is an equipment
enclosure comprising front, rear and side portions and an interior
chamber, a heat exchanger mounted within the interior chamber, a
centrifugal fan mounted to the heat exchanger for drawing ambient
air, the fan being separated from the interior chamber, a top cover
forming a fan casing for the centrifugal fan mounted to the front
and rear portions, the top cover including oppositely disposed
passageways extending from the fan casing to a periphery of the top
cover, and an air chamber in the top cover.
[0009] An object of the present invention is to provide a cover for
electronic equipment enclosures which has good thermal insulation
qualities, good acoustical suppression qualities and sufficient
strength for effective use. Another aim of the present invention is
to provide a cover for electronic equipment enclosures which is
relatively easy and inexpensive to manufacture and which is easy to
assemble with the remainder of an enclosure. Still another
advantage of the present invention is to provide a cover for
electronic equipment enclosures which is relatively light in
weight. Further aspects of the present invention are to provide a
cover which controls rain water runoff and which handles high wind
conditions through the use of a dual exit for heat exchanger
exhaust. Yet still other objects of the present invention are to
provide a more powerful heat exchanger and an exhaust system that
prevents blockage of the exhaust air from the heat exchanger.
[0010] A more complete understanding of the present invention and
other objects, aspects, aims and advantages thereof will be gained
from a consideration of the following description of the preferred
embodiment read in conjunction with the accompanying drawings
provided herein.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0011] FIG. 1 is a front perspective view of an electronic
equipment enclosure.
[0012] FIG. 2 is a diagrammatic side elevational view of the
enclosure of FIG. 1.
[0013] FIG. 3 is a top isometric view of an enclosure cover.
[0014] FIG. 4 is a bottom isometric view of the cover shown in FIG.
3.
[0015] FIG. 5 is a sectional, side elevational view of the cover
taken along line 5-5 of FIG. 3.
[0016] FIG. 6 is an enlarged fragmentary view of a portion of FIG.
5 taken within the circle 6-6 of FIG. 5.
[0017] FIG. 7 is a sectional, front elevational view of the cover
taken along line 7-7 of FIG. 3.
[0018] FIG. 8 is an enlarged fragmentary view of a portion of FIG.
7 taken within the circle 8-8 of FIG. 7.
DETAILED DESCRIPTION OF THE INVENTION
[0019] While the present invention is open to various modifications
and alternative constructions, the preferred embodiment shown in
the drawings will be described herein in detail. It is understood,
however, that there is no intention to limit the invention to the
particular form disclosed. On the contrary, the intention is to
cover all modifications, equivalent structures and methods, and
alternative constructions falling within the spirit and scope of
the invention as expressed in the appended claims.
[0020] An electronic equipment enclosure or cabinet typically is a
free standing box-like structure located out-of-doors where it is
bolted to a concrete slab and where it is exposed to the sun, rain,
wind and other environmental and climatic elements. These
enclosures or cabinets are designed to house a variety of
electronic equipment, for example, digital loop carriers, fiber
optic transport systems, radio equipment for wireless applications,
and remote power systems as well as telephone equipment. Because
the enclosure is situated out-of-doors, there is a need to be
concerned about such matters as high temperatures and direct
exposure to the sun on the one hand and hurricane weather on the
other as well as impacts from such items as bullets and pellets.
Referring now to FIGS. 1 and 2, there is illustrated such an
enclosure 10 having a front wall 12 with two access doors 14 and
16, a pair of sidewalls, such as the wall 18, and a rear wall 20
also having two access doors (not shown). In addition, the
enclosure includes a top cover 22. The enclosure includes a sealed
upper chamber 24 for the electronic equipment and a back-up battery
lower chamber 26 which is open to ambient air. The back-up battery
28 is useful should there be an electrical outage. The electronic
equipment, fiber optics, radio equipment or the like 30, 31 is
located in the sealed upper chamber 24 attached to racks that also
provide a frame for the enclosure. The enclosure is also provided
with a heat exchanger 32 because the electronic equipment generates
heat. Heat build up may also be caused by solar impingement. As
shown in FIG. 2, the heat exchanger draws in outside air
represented by the arrows 34 through louvers 35 into the bottom
chamber 26 and into the heat exchanger 32. This intake of outside
air is accomplished by a powerful centrifugal fan 36 at the top of
the heat exchanger. The air is then passed through an exhaust duct
38 and exhausted to the ambient air through a screen 40 as depicted
by the arrow 42. This movement of air, in addition to supplying
cool air to the heat exchanger, also ventilates the lower chamber
26 to prevent any undesirable gas or heat build-up from the
batteries 28.
[0021] The heat exchanger 32 is known as a dual air, vertical flow
device. Heated air from the sealed upper chamber 24 represented by
the phantom curves 44, 45 travels in a circular pattern where it is
cooled in the heat exchanger. This heated air from the equipment in
the sealed upper chamber is sucked through openings 46, 48 in the
upper portion of the heat exchanger and then is drawn downwardly by
fans 50, 51 at the bottom of the heat exchanger. In the process,
heat is transferred from the hot, downwardly moving equipment air
to the cool upwardly moving ambient air. The cooled equipment air
is exhausted through vents 52, 54 near the bottom of the heat
exchanger 32. As can be appreciated, the equipment air from the
sealed chamber 24 never mixes with the cooling ambient air.
[0022] Each part of the enclosure 10 should be specifically
designed to create an efficient and effective cabinet structure.
The present invention involves an improved top cover 22 that
provides for a more effective and efficient cabinet. The cover 22
has an upper panel 58, FIG. 3 of synthetic resin material with a
length represented by the line 60, a width represented by the line
62, an edge portion 64 and a periphery 66. The top cover also
includes a lower panel 70, FIG. 4, made of a similar synthetic
resin material and having generally the same or very similar length
72, width 74, edge portion 76, FIG. 6, and periphery 78 as the
upper panel 58. The upper panel includes an additional layer or
"cap stock" to provide UV protection. Typically, the bottom panel
does not need such a layer.
[0023] The upper panel and the lower panel are sealed together by
ultrasonic welding at their edge portions 64, 76, FIG. 6. By doing
this, an air chamber 79 is formed which helps the top cover to act
as a thermal insulator to solar impingement. Two access ports 80,
82 are provided in the top cover (FIGS. 3 and 4) to allow access to
the heat exchanger fans, such as the fan 36, FIG. 2. These access
ports are covered with lids, such as a lid 84, FIG. 3. If there is
a need to service or replace the heat exchanger fans, this can be
easily accomplished by removing the lids to expose the fans.
[0024] Referring to FIG. 8, a rim 85 around the access port 82 is
shown in more detail. The rim includes a groove 86 located just
outwardly of the port. The groove is present to seat an O-ring seal
for weatherproofing the port. Beyond the groove 86 in a radial
direction is a fastener sleeve 88 for receiving a fastener, such as
a screw (not shown), that goes through a fastener opening 90, FIG.
3 of the lid 84. The weather sealing of the port becomes effective
when the lid 84 is tightened downwardly by fasteners on the seal
located in the groove 86.
[0025] To maintain weather tightness of the sealed chamber 24,
another seal or gasket (not shown) is provided between the upper
edges of the front and side walls and the lower panel 70. All doors
also have peripheral seals. The material of the seals may be
ethylene propylene diene methylene or "EPDM" and is well known by
those skilled in the sealing art. The material of the upper and
lower panels may be of a PVC blend sold under the Royalite R 87/59
brand by Spartech of South Bend, Ind.
[0026] Referring now to FIG. 5, the upper panel 58 has an upper
surface 92 which has a slightly bowed shape across its width. The
upper panel may also have a slightly bowed shape across its length.
The bowed shape ensures that rainwater will run off the cover
toward the periphery 66. To prevent rainwater from coming down in
front of the access doors 14, 16 of the front wall 12 or the doors
of the rear wall 20, length-wise extending berms 100, 102, FIGS. 3,
5 and 6 are provided at the periphery which extend almost the
entire length of the cover as shown in FIG. 3. As readily seen in
FIGS. 5 and 6, the berms provide a barrier to the flow of
rainwater. Another pair of parallel berms 104, 106 extend along
most of the width of the cover. This arrangement leaves four corner
portions 110, 112, 114 and 116 without a berm or barrier to the
flow of rainwater. Thus, a technician working with the electronics
equipment in the upper chamber 24 through an open set of doors will
not be exposed to runoff rainwater during a rain storm. Instead,
the water will be directed to one or more of the four comer
portions before dropping to the ground.
[0027] Referring now to FIGS. 4, 5 and 7, the lower panel 70 is
shown to have a very uneven surface so that in numerous sectional
views, the lower panel has a corrugated profile. For example,
portions of the lower panel have low horizontal surfaces such as
the surface 120 and high horizontal surfaces such as the surface
122. In addition, the lower panel also has generally vertically
disposed surfaces such as the surface 124. By repeating this
pattern of corrugation, the strength of the lower panel is greatly
enhanced. At the same time, the air chamber 79 is still maintained
for purposes of thermal insulation.
[0028] Six fastener openings 130, 132, 134, 136, 138 and 140, FIG.
4, are provided near the periphery 78 so when assembled, the top
cover may be attached to the remainder of the enclosure from within
the enclosure. Thus, there are no attachment openings or fasteners
exposed to the weather or for tampering.
[0029] Four additional fastener openings 142, 144, 146 and 148 are
provided but these extend through both the upper and the lower
panels. These openings align with the frame in the upper chamber so
that eye bolts (not shown) may be passed through the top cover and
attached to the frame to provide a strong connection to allow
lifting of the entire enclosure for transport and installation.
Once the enclosure is secured to a concrete foundation pad, the eye
bolts may be removed and replaced with weatherproof plugs.
[0030] Two lateral passageways or ducts 150, 152, FIG. 4, are
formed in the lower panel in the immediate vicinity of the two
access ports 80, 82. Two scroll fan casings 147, 149 are also
formed in the lowe panel around the two access ports. Beneath the
access ports are centrifugal fans, such as the fan 36. These fans
are more powerful than those previously used and thus, provide more
effective heat exchange. The fans are positioned so as to rotate
about a vertical axis and exhaust air in a horizontal direction.
When the cover is attached to the rest of the cabinet, the
centrifugal fans push the exhaust air from the heat exchanger to
the right when viewed in FIG. 4, through the passageways 150, 152
and out through stainless steel screens 154, 156 which are sonic
welded to the bottom panel. Supplemental passageways or ducts 151,
153 are provided extending in the opposite direction, that is, to
the left so that exhaust air may exit through the passageways 151,
153 and stainless steel screens 160 and 162 if, for example, the
pressure at the screens 154 and 156 is too great for the fans to
overcome. Such a situation may arise during a hurricane when strong
winds, shown graphically in FIG. 2, blow against one side of the
enclosure. If that side is the usual exit of the heat exchanger
exhaust air, the pressure created by the wind may be greater than
that generated by the fans. When this happens and if there is only
one exhaust passageway, the fan will cease turning. To overcome
this potential problem, an alternative path in the opposite
direction is provided. With this technique, the heat exchanger fans
are capable of operating even under severe weather conditions.
Also, if the high winds are accompanied by heavy rain, water may be
driven through the screens 154, 156 and into the passageways 150,
152. Providing the oppositely directed passageways 151, 153 allows
the water to be driven through the cover instead of being forced
into the cabinet through the fan. This flow by-pass arrangement
means there will be no water build up or leakage.
[0031] A suitable centrifugal fan may be acquired from EBM/Papst of
Farmington, Conn. The fan diameter is about 225 mm (or just under 9
inches) with a capacity of about 300 cfm at a pressure of one inch
of water.
[0032] The upper and lower panels are made from the PVC blend
mentioned above and are thermoformed. Molded stiffening members may
be included during the forming operation to strengthen the cover.
Wall thickness after forming is about 0.100 inches whereas the
thickness of the panels before forming are about 0.125 inches. The
length and width of the cover may vary depending upon the size of
the cabinet; currently, the length may vary between 42 and 90
inches, and the width may be about 46.5 inches. The height of the
cover (without lids) may be about 2.6 inches. The diameter of the
access ports is about 14 inches. The exhaust air/water ducts may be
about 5.5 inches wide.
[0033] It can now be readily appreciated that the inventive top
cover provides efficient and effective thermal insulation as well
as noise suppression. This is because of such features as the air
space between the upper and lower panels and the use of synthetic
resin which is inherently more dense than metal so as to resonate
at a much higher frequency than metal. In addition, the inventive
top cover has an air/water exhaust and a flow by-pass duct system
that allows the heat exchanger fans to operate even under severe
high pressure and wet circumstances. Further, the top cover has
good strength characteristics and once capital expenditures are
made, is easy to fabricate and handle because of the relatively low
weight. With regard to manufacturing and assembly, a major
advantage is that there will be no need to go through a complicated
welding, machining and painting operation. Furthermore, since the
panels are molded, it is easy to include the rain barrier berms for
directing the rain out of the way of the access doors in the front
and rear walls.
[0034] The specification describes in detail an embodiment of the
present invention. Other modifications and variations will, under
the doctrine of equivalents, come within the scope of the appended
claims. For example, different dimensions and geometries or
different materials are considered equivalent structures. Still
other alternatives will also be equivalent as will many new
technologies. There is no desire or intention here to limit in any
way the doctrine of equivalents.
* * * * *