U.S. patent application number 09/471045 was filed with the patent office on 2002-04-25 for waterproof enclosure for electrical devices.
Invention is credited to ALBA, GENARO FLORES, KERR, WILLIAM W. JR., LEWIS, MELANIE A., STENDARDO, RICHARD J., VRNAK, THOMAS F..
Application Number | 20020046853 09/471045 |
Document ID | / |
Family ID | 23870047 |
Filed Date | 2002-04-25 |
United States Patent
Application |
20020046853 |
Kind Code |
A1 |
STENDARDO, RICHARD J. ; et
al. |
April 25, 2002 |
WATERPROOF ENCLOSURE FOR ELECTRICAL DEVICES
Abstract
A waterproof enclosure (100) for electrical devices includes a
front frame (114), a base plate (116), and a roof assembly (118)
attached to a component mounting section (120). Front frame (114)
extends from the front of component mounting section (120), and
includes doors (122) for protecting electrical components mounted
within the component mounting section (120). Roof assembly (118) is
attached to the top of front frame (114) and component mounting
section (120) for preventing the ingress moisture into front frame
(114) and component mounting section (120). Roof assembly (118)
includes ventilation channels (124, 126, 128, 130) disposed along
the length of caps (132, 134, 136) to increase air flow through the
enclosure (100) for cooling the electrical components mounted
therein.
Inventors: |
STENDARDO, RICHARD J.;
(DURHAM, NC) ; KERR, WILLIAM W. JR.; (CLARKSVILLE,
TN) ; LEWIS, MELANIE A.; (DURHAM, NC) ; VRNAK,
THOMAS F.; (CHAPEL HILL, NC) ; ALBA, GENARO
FLORES; (SALAMANCA, MX) |
Correspondence
Address: |
GENERAL ELECTRIC COMPANY
41 WOODFORD AVENUE
PLAINVILLE
CT
06002
US
|
Family ID: |
23870047 |
Appl. No.: |
09/471045 |
Filed: |
December 22, 1999 |
Current U.S.
Class: |
174/50.5 |
Current CPC
Class: |
H02B 1/28 20130101; H01F
27/02 20130101; H05K 7/20009 20130101 |
Class at
Publication: |
174/50.5 |
International
Class: |
H01J 005/00; H01J
015/00 |
Claims
What is claimed is:
1. A roof assembly forming the top of an enclosure for electrical
devices, the roof assembly including: a first hood formed from a
sheet of waterproof material, said first hood extending across a
portion of the top of the enclosure; a cap extending above a
portion of said first hood; and a first channel extending between
said cap and said first hood, said first channel allowing the
passage of air into and out of the enclosure.
2. The roof assembly of claim 1, wherein said first hood includes a
first flange extending upward from an edge formed on said first
hood; and wherein said cap includes a top portion extending above
said first flange, and a second flange extending downward from a
side edge of said top portion, said first channel extending between
said first and second flanges.
3. The roof assembly of claim 2, wherein said first flange includes
a first lip disposed along a free edge of said first flange, said
first lip extending above said hood, and said second flange
includes a second lip disposed along a free edge of said second
flange, said second lip extending beneath said top portion, said
first channel extending between said first lip and said second
lip.
4. The roof assembly of claim 2, wherein said cap includes an cave
disposed between said top portion and said second flange, said eave
extending at a downward angle from a side edge of said top portion,
and said second flange extending downward from a side edge of said
eave.
5. The roof assembly of claim 1, wherein said cap further extends
above a lifting lug attached to a frame of the enclosure.
6. The roof assembly of claim 1, further including a screen vent
attached between said cap and said first hood for preventing
objects from entering said enclosure.
7. The roof assembly of claim 1 wherein said first hood, said cap,
and said channel extend along an entire length of the roof
assembly.
8. The roof assembly of claim 1, further including: a second hood
formed from a sheet of waterproof material, said second hood
extending across another portion of the top of the enclosure, said
cap extending above a portion of said second hood, and a second
channel extending between said cap and said second hood, said
second channel allowing the passage of air into and out of the
enclosure.
9. The roof assembly of claim 8, further including: a first flange
extending upward from a first edge formed on said first hood; a
second flange extending upward from a second edge formed on said
second hood; and wherein said cap includes a top portion extending
above said first and second flanges, and third and fourth flanges
extending downward from side edges of said top portion, said first
channel extending between said first and third flanges, and said
second channel extending between said second and fourth
flanges.
10. The roof assembly of claim 8, further including: a first screen
vent attached between said cap and said first hood; and a second
screen vent attached between said cap and said second hood, said
first and second screen vents for preventing objects from entering
the enclosure.
11. The roof assembly of claim 8, wherein said first and second
hoods, said cap, and said first and second channels extend along an
entire length of the roof assembly.
12. The roof assembly of claim 8, wherein said cap further extends
above a lifting lug disposed between said first and second
hoods.
13. A waterproof enclosure for electrical devices, the waterproof
enclosure comprising: a component mounting section having a rear
panel and side panels, said rear panel and said side panels forming
a compartment for mounting electrical devices; a front frame having
side walls and a door, said side walls extending from said side
panels and said door extending between said side walls; a roof
assembly forming a top of the enclosure, the roof assembly
including: a first hood formed from a sheet of waterproof material,
said first hood extending across a portion of the top of the
enclosure; a cap extending above a portion of said first hood, and
a first channel extending between said cap and said first hood,
said first channel allowing the passage of air into and out of the
enclosure.
14. The waterproof enclosure of claim 13, wherein the enclosure is
shaped substantially as a rectangular prism having first, second,
third, and fourth sides, a bottom and said top; said first side
being formed by said rear panel, said second side being formed by
one of said side panels and one of said side walls, said third side
being partially formed by said door, and said fourth side being
formed by another of said side panels and another of said side
walls.
15. The roof assembly of claim 13, wherein said hood includes a
first flange extending upward from an edge formed on said first
hood; and wherein said cap includes a top portion extending above
said first flange, and a second flange extending downward from a
side edge of said top portion, said first channel extending between
said first and second flanges.
16. The roof assembly of claim 15, wherein said first flange
includes a first lip disposed along a free edge of said first
flange, said first lip extending above said hood; and said second
flange includes a second lip disposed along a free edge of said
second flange, said second lip extending beneath said top portion,
said first channel extending between said first lip and said second
lip.
17. The roof assembly of claim 15, wherein said cap includes an
eave disposed between said top portion and said second flange, said
eave extending at a downward angle from a side edge of said top
portion, and said second flange extending downward from a side edge
of said eave.
18. The roof assembly of claim 13, wherein said cap further extends
above a lifting lug attached to a frame of the enclosure.
19. The roof assembly of claim 13, further including a screen vent
attached between said cap and said first hood for preventing
objects from entering said enclosure.
20. The roof assembly of claim 13 wherein said first hood, said
cap, and said channel extend along an entire length of the roof
assembly.
21. The roof assembly of claim 13, further including: a second hood
formed from a sheet of waterproof material, said second hood
extending across another portion of the top of the enclosure, said
cap extending above a portion of said second hood, and a second
channel extending between said cap and said second hood, said
second channel allowing the passage of air into and out of the
enclosure.
22. The roof assembly of claim 21, further including: a first
flange extending upward from an edge formed on said first hood; a
second flange extending upward from an edge formed on said second
hood; and wherein said cap includes a top portion extending above
said first and second flanges, and third and fourth flanges
extending downward from side edges of said top portion, said first
channel extending between said first and third flanges, and said
second channel extending between said second and fourth
flanges.
23. The roof assembly of claim 21, further including: a first
screen vent attached between said cap and said first hood; and a
second screen vent attached between said cap and said second hood,
said first and second screen vents for preventing objects from
entering said enclosure.
24. The roof assembly of claim 21, wherein said first and second
hoods, said cap, and said first and second channels extend along an
entire length of the roof assembly.
25. The roof assembly of claim 21, wherein said cap further extends
above a lifting lug disposed between said first and second hoods.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to enclosures for
electrical components and, more particularly, to a waterproof
enclosure for electrical devices.
[0002] Enclosures are used in electrical power distribution systems
to house various electrical components. These enclosures protect
the electrical distribution equipment mounted therein from damage.
Such applications include electrical switchboards, switchgear, and
motor control centers. The degree of protection provided by the
enclosure is dictated by the area in which the enclosure is to be
located. The National Electrical Manufacturer's Association (NEMA)
defines different types of enclosures by the location of the
enclosure and the various elements that the enclusure must be able
to withstand. For example, NEMA Type 3 enclusres are for outdoor
use, and NEMA Type 3R must provide a degree of protection agains
falling rain, sleet, and external ice formation. Enclosures may
also be designed to meet waterproof ratings as listed in
Underwriters Laboratories standard 891 section 35 and ANSI/IEEE
standard C37.20.3-1987 Section 5.2.9.
[0003] A typical outdoor enclusure (e.g., NEMA Type 3R) is shown in
FIGS. 1 and 2. The switchboard type enclosure 10 includes a front
frame 12 and a roof assembly 14 attached to a switchboard section
16. Switchboard section 16 is an indoor type enclosure (e.g., NEMA
Type 1 or 2), which includes a metal cover secured to a frame 18
and forming side covers 20 and back cover 22. Mounted within
switchboard section 16 are a plurality of electrical devices such
as circuit breakers, fusible switches, motor controllers, or other
electrical components (not shown). Front frame 12 is attached to
the perimeter of the switchboard section 16. Front frame 12
includes walls 24 extending forward from side covers 20, and a door
26. Walls 24 and door 26 protect the electrical components within
switchboard section 16 from the elements, while door 26 allows
personnel to access these electrical devices. A handle 28 with
provisions for a padlock prevent unauthorized access to the
electrical devices. Roof assembly 14 includes a sloped hood 30 that
extends across the width of switchboard section 16 from side 20 to
side 20. Hood 30 extends a distance (shown here as five inches)
past the back cover 22 of switchboard section 16 and past the front
of door 26. Front and rear edges of hood 30 include flanges 32, 34
that extend downwardly. Secured between flange 32 and front frame
12 and between flange 34 and rear frame 16 are a pair of screen
vents 36, which both extend across the width of hood 30. Typically,
the screen vents 36 are formed of wire or foam filters to keep out
water, debris, and insects. A pair of caps 38 are disposed along
the edges of hood 30 adjacent sides 20, 24.
[0004] An exploded view of roof assembly 14 is shown in FIG. 3.
Referring to FIGS. 2 and 3, hood 30 includes mounting flanges 50
which extend along sides of hood 30. Flanges 50 of hood are secured
to lifting brackets 52. Lifting brackets 52 are secured to the
frame 18 of switchboard section 16 and extend along the entire
length of hood 30. Lifting brackets 52 provide a lifting point on
enclosure 10 if it is necessary to move enclosure 10. Once
enclosure 10 is in position, caps 38 are secured to flanges 50. An
optional center lifting bracket 54 and center cap 56 are shown for
use with switchboard sections 16 having a portion of the frame 18
extending through the center of the switchboard section 16.
[0005] The enclosure 10 shown in FIGS. 1-3 uses front and rear
overhangs, formed by the extension of roof assembly 14 past back
cover 22 and front of door 26, to vent heat from the electrical
devices mounted within the enclosure. However, the rear overhang
increases the area the customer must allocate to the equipment by
adding, for example, five inches of depth betwen the back cover 22
of the equipment and any any object next to which one would place
it.
[0006] In applications of the enclosure 10 of FIGS. 1-3, if a rear
overhang cannot be used, the entire roof assembly must be shifted
so that the flange 34 on the rear of hood 30 is flush with the back
cover 22. However, this modification eliminates the convective flow
of air through the enclosure 10. Indeed, in enclosures 10 where
such a modification is made, the ampere rating of the enclosure
must be reduced. In addition, this modification increases the
amount of overhang on the front of the enclosure 10.
[0007] It is therefore desirable to provide an enclosure for
electrical components having reduced space requirements through
removal of the rear overhang, while providing sufficient
ventilation to prevent overheating of the internal electrical
components, and while meeting waterproof ratings listed in
Underwriters Laboratories standard 891 section 35 and ANSI/IEEE
standard C37.20.3-1987 Section 5.2.9.
BRIEF SUMMARY OF THE INVENTION
[0008] In an exemplary embodiment of the invention, a roof assembly
forms the top of an enclosure for electrical devices. The roof
assembly includes a hood formed from a sheet of waterproof
material. The hood extends across a portion of the top of the
enclosure. A cap extends above a portion of the hood, and a channel
extends between the cap and the hood. The channel allows the
passage of air into and out of the enclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a front view of an enclosure of the prior art;
[0010] FIG. 2 is a side view of the enclosure of FIG. 1;
[0011] FIG. 3 is an exploded perspective view of the roof assembly
of FIG. 1;
[0012] FIG. 4 is a perspective view of an enclosure of the present
invention;
[0013] FIG. 5 is a side view of detail "A" of the enclosure of FIG.
4;
[0014] FIG. 6 is a side view of detail "B" of the enclosure of FIG.
4;
[0015] FIG. 7 is a front view of section "D-D" of the enclosure of
FIG. 4;
[0016] FIG. 8 is a front view of section "C-C" of the enclosure of
FIG. 4;
[0017] FIG. 9 is an exploded perspective view of an side cap of the
enclosure of FIG. 4; and
[0018] FIG. 10 is an exploded perspective view of a center cap of
the enclosure of FIG. 4.
DETAILED DESCRIPTION OF THE INVENTION
[0019] FIG. 4 is a perspective view of a waterproof enclosure of
the present invention, generally shown at 100. The enclosure 100 is
shaped substantially as a rectangular prism having four sides 102,
104, 106, 108, a top 110, and a bottom 112. The enclosure 100
includes a front frame 114, a base plate 116, and a roof assembly
118 attached to a component mounting section 120. Front frame 114
extends from the front of component mounting section 120, and
includes doors 122 for protecting electrical components (not shown)
mounted within the component mounting section 120. Front frame 114
and component mounting section 120 are secured to substantially
rectangular base plate 116, which forms the bottom 112 of enclosure
100. Roof assembly 118 is attached to the top of front frame 114
and component mounting section 120 for preventing the ingress
moisture into front frame 114 and component mounting section 120.
Roof assembly 118 includes ventilation channels 124, 126, 128, 130
disposed along the length of caps 132, 134, 136 to increase air
flow through the enclosure 100 for cooling the electrical
components mounted therein, as is described in further detail
hereinafter.
[0020] Component mounting section 120 includes an internal frame
138 with side panels 140 and a back panel 142 attached to the frame
138. Back panel 142 is a substantially rectangular plate extending
the entire height and width of the enclosure 100 to form the back
side 108 of the enclosure 100. Side panels 140 are substantially
rectangular plates that extend perpendicularly from the side edges
of back panel 142 to form a portion of sides 102, 106 of the
enclosure 100. Mounted within component mounting section 120 are a
plurality of electrical devices (not shown) such as circuit
breakers, fusible switches, motor controllers, or other electrical
devices. The electrical devices are electrically connected to an
electrical distribution circuit (not shown), a portion of which
passes into enclosure 100 via holes (not shown) in the back panel
142 or base plate 116. Component mounting section 120 may comprise,
for example, a switchboard, switchgear, or motor control mounting
cabinet.
[0021] Front frame 114 includes walls 144 which extend forward
from, and substantially parallel to, side panels 140 of the
component mounting section 120. Walls 144 and side plates 140 form
sides 102, 106 of the enclosure 100. Doors 122 are hingedly
attached to walls 144, and form the front side 104 of the enclosure
100. An internal frame 146 provides support to walls 144 and doors
122. Walls 144 and doors 122 protect the electrical components
mounted within the component mounting section 120 from the
elements, while doors 122 allow personnel to access these
electrical devices. A handle 148 with provisions for a padlock
prevent unauthorized access to the electrical devices.
[0022] Roof assembly 118 forms the top 110 of enclosure 100. Roof
assembly 118 includes side caps 132, 136 and center cap 134 that
extend substantially parallel to sides 102, 106 along top 110. Roof
assembly 118 further includes hoods 150, 152. Hood 150 extends
between caps 132 and 134, along the length of these caps.
Similarly, hood 152 extends between caps 134 and 136, and along the
length of these caps. Hoods 150 and 152 may be sloped from front
104 to the back 108 of the enclosure 100 to allow any moisture
which may collect on hoods 150 and 152 to drain off of the
enclosure 100.
[0023] Caps 132, 134, 136, and hoods 150, 152 are constructed of a
waterproof material such as steel or plastic.
[0024] FIGS. 5 and 6 show side views of detail "A" and detail "B"
in FIG. 4. While hood 152 and side cap 136 are shown, this
arrangement is typical for hood 150 and caps 132, 134 as well. Hood
152 includes front and back flanges 154, 156 that extend downward
from a top surface 158. Flanges 154, 156 are connected to end
portions 160, 162 of cap 136 by bolts 164 or similiar means. As
shown in FIG. 5, cap 136 and hood 152 extend a distance "x" (e.g.
five inches) past the front side 104 of enclosure 100. As in the
prior art, this overhang provides a ventillation duct between the
hood 152 and the front frame 114 for allowing air to flow into the
enclosure 100. A screen vent 166, formed of wire or foam filters,
is disposed between the front flange 154 and the front frame 114 to
keep out water, debris, and insects. Referring to FIG. 6, it can be
seen that back flange 156 of hood 152 is secured against the back
panel 142, with end portion 162 of cap 136 secured against back
flange 156 using bolts 164 or similar means. With the exception of
the thickness of flange 156, end portion 160, and bolts 164, which
protrude a distance (e.g., 1/2 inch) from back panel 142, there is
no overhang in the back of enclosure 100.
[0025] Referring now to FIG. 7, a front view of section "D-D" of
the enclosure 100 of FIG. 4 is shown. While hood 152 and side cap
136 are shown, this arrangement is typical for hood 150 and side
cap 132 as well. Hood 152 includes a side flange 200 extending
along the side edge of top surface 158 and substantially
perpendicular thereto. A lip 202 extends perpendicularly from a
free edge of side flange 200. Side cap 136 includes a side surface
204, which extends parallel to, and in intamate contact with, frame
146 of front frame 114. Side cap 136 also includes a top surface
206, extending perpendicularly from side surface 204, and a flange
208, which extends from top surface 206 in a direction
substantially parallel to side surface 204. A lip 210 extends
perpendicularly from a free edge of flange 208. Channel 130 is
formed between lip 210 and top surface 158, lip 210 and lip 202,
and lip 202 and top surface 206. Channel 130 extends along the
entire length of side cap 136, from back side 108 of enclosure 100
to front side 104 of enclosure 100 (see FIG. 1). Channel 130 allows
the exhaust of warm air from the enclosure 100. The ingress of
moisture is prevented by the tortuous path created for the air
flow, with lips 202 and 210 preventing drops of water bouncing off
of hood 152 from entering enclosure 100.
[0026] A lifting lug 212 is secured to frame 138 of component
mounting portion 120 (see FIG. 1) by welding or similar process.
Lifting lug 212 includes a u-shaped bracket 214 with a bolt 216
extending from one side of the u-shaped bracket 214 to the other.
Lifting lug 212 provides a lifting point on enclosure 100 if it is
necessary to move enclosure 100. Lifting lug 212 also includes an
L-shaped extension 218 depending from the bottom of the u-shaped
bracket 214 and extending upward therefrom to contact side flange
200 of hood 152. Side flange 200 of hood 152 is secured to L-shaped
extension 218 by bolts or similar means.
[0027] Referring to FIG. 8, a front view of section "C-C" of the
enclosure 100 of FIG. 4 is shown. Hoods 150 and 152 each include a
side flange 250 extending along the side edge of top surface 158
and substantially perpendicular thereto. A lip 252 extends
perpendicularly from a free edge of side flange 250. Center cap 134
includes a top portion 254 with eaves 256 extending at an angle
(e.g. 45 degrees) downward from side edges of top portion 254. A
lip 258 extends downward from the free edge of each eave 256.
Channels 126, 128 are formed on either side of cap 254 between lip
258 and top surface 158, lip 252 and eave 256. Channels 126, 128
extend along the entire length of center cap 134, from back side
108 of enclosure 100 to front side 104 of enclosure 100 (see FIG.
1). Channels 126, 128 allow the exhaust of warm air from the
enclosure 100. The ingress of moisture is prevented by the tortuous
path created for the air flow. If any drops of water should collect
on the underside of center cap 134, the downward angle of the eaves
256 will drain this water back onto the hoods 150, 152. The slope
of hood 152 will cause this water to drain off of the enclosure
100.
[0028] A pair of lifting lugs 212 are secured to frame of component
mounting portion by welding or similar process. Side flanges 250 of
hoods 150, 152 are secured to L-shaped extensions 218 of lifting
lugs 212 by bolts or similar means.
[0029] Referring to FIG. 9, an exploded perspective view of side
cap 136 is shown. While hood 152 and side cap 136 are shown, this
arrangement is typical for hood 150 and side cap 132 as well. Holes
300 in end portion 160 of cap 136 align with holes 302 in front
flange 154 of hood 152, for accepting bolts 164 (FIG. 5) to secure
cap 136 to hood 152. Holes 304 in lip 202 of hood 152 accept screws
306 for securing a screen vent 308, formed of wire or foam filters,
thereto. Screen vent 308 helps to keep water, debris, and insects
from entering the channel formed between cap 136 and hood 152. A
pair of lifting lugs 212 are secured to frame 138 of component
mounting portion 120 and to side flange 200 of hood 152. As can be
seen, lifting lugs 212 extend along only a small portion of side
106. Therefore, lifting lugs 212 obstruct only a small portion of
the channel formed between cap 136 and hood 152.
[0030] Referring to FIG. 10, an exploded perspective view of center
cap 134 is shown. Holes 350 in end portion 160 of cap 134 align
with holes 352 in front flanges 154 of hoods 150, 152, for
accepting bolts 164 (FIG. 5) to secure cap 134 to hoods 150, 152.
Holes 354 in lips 252 of hoods 150, 152 accept screws 356 for
securing a screen vents 358, formed of wire of foam filters,
thereto. Screen vents 358 helps to keep water, debris, and insects
from entering the channels formed between center cap 134 and hoods
150, 152. Lifting lugs 212 are secured to frame 138 of component
mounting portion 120 and to side flanges 250 of hoods 150, 152.
Lifting lugs 212 extend along only a small portion of the space
between hoods 150, 152. Therefore, lifting lugs 212 obstruct only a
small portion of the channels formed between hoods 150, 152 and cap
134.
[0031] The waterproof enclosure of the present invention, by
removing the need for a rear overhang, reduces space requirements
from those required for prior art enclosures. The waterproof
enclosure described herein uses ventilation channels disposed along
the length of caps to increase air flow through the enclosure for
cooling the electrical components mounted therein. With the
ventilation channels described herein, a chimney effect is created,
allowing heated air rising off the equipment to exit through the
channels. These channels have been shown to provide improved
ventilation over the prior art design. This design has also been
shown to meet waterproof ratings listed in Underwriters
Laboratories standard 891 section 35 and ANSI/IEEE standard
C37.20.3-1987 Section 5.2.9.
[0032] While the invention has been described with reference to a
preferred embodiment, it will be understood by those skilled in the
art that various changes may be made and equivalents may be
substituted for elements thereof without departing from the scope
of the invention. In addition, many modifications may be made to
adapt a particular situation or material to the teachings of the
invention without departing from the essential scope thereof.
Therefore, is intended that the invention not be limited to the
particular embodiment disclosed as the best mode contemplated for
carrying out this invention, but that the invention will include
all embodiments falling within the scope of the appended
claims.
* * * * *