Abstrict An electronic layout of an electronic exit sign, that encompasses
the entire electronic packaging and lighting inside the exit sign
enclosure. The layout includes brackets that function both as a
method for holding LEDs for illuminating the sign, and as enclosures
for enclosing the electronics of a controller and a power unit.
The LEDs are mounted to the brackets and held by nylon buttons.
A battery pack for battery backup and a battery backup self-test
switch is mounted to a releasable plate. This allows the battery
backup feature to be an option and also allows for easy replacement
of discharged batteries. The LEDs are spaced in such a way as to
provide uniform lighting to both the exit sign and a chevron symbol.
The LEDs are positioned so that the same unit can drive either a
single or double face exit.
Claims What is claimed is:
1. An exit sign assembly comprising:
an enclosure housing having a front portion, a rear portion, a
first side portion, a second side portion spaced from and opposing
the first side portion, an upper portion and a lower portion;
a plate having an exit legend located thereon in at least one of
the front portion and the rear portion, said plate being located
between the first side portion and the second side portion;
a power unit in the first side portion for transmitting electric
power;
first bracket means for holding said power unit in the first side
portion;
a first LED lamp assembly comprising a set of LED lamps, said LED
lamp assembly being connected to said first bracket means to secure
said first LED lamp assembly in said first side portion for extending
along one side of said plate;
a second LED lamp assembly comprising a set of LED lamps, said
second LED lamp assembly secured in said second side portion; and
said first and second LED lamp assemblies being electrically connected
to said power unit for being illuminated upon the generation of
electrical power by said power unit;
a down plate mounted in said lower portion, and a battery pack
electrically connectable to said first and second LED lamp assemblies,
and a manually accessible test switch for testing the operation
of said battery pack for illuminating said first and second LED
lamp assemblies, mounted on said down plate;
a controller for sensing the failure of said power unit to transmit
electrical power and for relaying battery pack voltage to said LED
lamp assemblies, said controller being mounted in said first side
portion.
2. An exit sign assembly according to claim 1 wherein the exit
legend on said plate includes the word EXIT and a pair of chevrons
in each of side in said first side portion and said second side
portion, and each of said LED lamp assemblies has a LED bulb located
adjacent one of said chevrons.
3. An exit sign assembly according to claim 1 wherein said exit
sign assembly comprises said plate mounted in the front portion
and a second plate having an exit legend mounted in the rear portion,
and wherein said first LED lamp assembly and said second LED lamp
assembly illuminate both of said plates.
4. An exit sign assembly according to claim 1 wherein said down
plate is removable to enable the changing of said battery pack.
5. An exit sign assembly according to claim 1 and further comprising
a battery pack operably connected to said first and second LED lamp
assemblies, a test switch assembly for testing the operation of
said battery pack for illuminating said first and second LED lamp
assemblies, said test switch assembly including a test switch and
a receiver box for receiving remote electronic signals from a remote
control unit, said receiver box being electrically connected to
said test switch for operating said test switch assembly to determine
if said battery pack can illuminate said first and second LED lamp
assemblies.
Description BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to an electronics layout
and more particularly to an improved electronics layout for an illuminated
exit sign.
2. Description of Prior Art
Exit signs that illuminate are used for many applications, such
as the inside of stores, parking garages, theatres, offices, industrial
plants and many others. The exit signs are usually comprised of
an enclosure, a plastic face on one or both sides, lights inside
the enclosure and electronics for illuminating the lights. The plastic
face usually has the word exit and an arrow or chevron embossed
on it in red with a white background. These units require a transformer
or power assembly for converting an AC power source to DC power
for turning on the lights within the enclosure. The lights are arranged
to provide light uniformly within the enclosure so the exit sign
illuminates at a particular brightness in dark or dim areas. Additionally,
in many commercial building applications these signs require a battery
backup source that will drive the exit sign with a specified brightness
in the event of a power loss.
Due to the arrangement of the lights or light emitting diodes (LEDs)
for providing uniform lighting within the enclosure, and the necessary
control circuitry needed to provide a battery backup, a separate
enclosure is necessary for the electronics. These enclosures are
sometimes referred to as canopies, and may contain the power assembly,
the control circuitry and batteries for battery backup. This is
especially the case in double face exit signs.
The present invention alleviates the need for using canopies (to
store components) by designing an electronic layout that allows
the entire electronic package to be contained in the exit sign housing.
Further, this invention provides a layout that can be used in both
single and double face exit signs.
SUMMARY OF THE INVENTION
In accordance with a preferred embodiment of the present invention,
the invention is an electronic layout of an electronic exit sign
that encompasses the entire electronic packaging and lighting inside
an exit sign enclosure. The layout includes brackets that function
both as a method for holding LEDs for illuminating the sign, and
also as enclosures for the electronics of a controller and a power
unit. The enclosure could be made from steel, or a comparable plastic
material, which is UL listed, for the purpose of preventing fire
or shock hazard. Nylon buttons provide an inexpensive way of installing
the LEDs and replacing burned out LEDs that are mounted to the brackets.
A battery pack for battery backup and a battery backup self-test
switch is mounted to a releasable or down plate. This allows the
battery backup feature to be an option and also allows for easy
replacement of discharged batteries. The LEDs are spaced in such
a way as to provide uniform lighting to both the exit sign and a
chevron symbol. The LEDs are positioned, so that the same unit can
drive either a single or double face exit.
An object of this invention is to provide a fully self-contained
electronic exit sign.
Another object of this invention is to provide a fully self-contained
electronic exit sign that includes a battery backup.
An additional object of this invention is to provide a fully self
contained electronic exit sign with a battery backup that includes
a battery backup self-test.
Another object of this invention is to provide a fully self contained
electronic exit sign that has uniform lighting for both an exit
word and a chevron symbol.
A further object of this invention is to provide a fully self-contained
electronic exit sign that can be used in a single face or double
face exit sign.
Another object of this invention is to provide an easy to manufacture,
easy to repair low cost electronic exit sign.
These and other objects will become apparent from the following
description of a preferred embodiment taken together with the accompanying
drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may take physical form in certain parts and arrangement
of parts, a preferred embodiment of which will be described in detail
in the specification and illustrated in the accompanying drawings
which form a part hereof, and wherein:
FIG. 1 is a front view of an electronic exit sign;
FIG. 2 is a top view of an electronic exit sign;
FIG. 3 is a front view of an electronic exit sign with the front
portion removed;
FIG. 4 is a front view of a LED stick;
FIG. 5 is a side view of a LED unit;
FIG. 6 is a view of the electronic exit sign shown in FIG. 3 with
an infra red receiver box; and
FIG. 7 is a front view of a remote control unit.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
Referring now to the drawings wherein the showings are for the
purpose of illustrating the preferred embodiment of the invention
only, and not for the purpose of limiting the same, FIG. 1 shows
a front view of a double faced illuminated electronic exit sign.
Exit sign 1 is comprised of a metallic enclosure or casing, with
the word EXIT and a chevron symbol cut out of the face of the enclosure.
The front portion of the enclosure has the word EXIT and the chevron
embossed onto plastic sheets 2 3. Typically, the letters of exit
sign 1 could be made with either six or eight inch letters. Sheets
2 and 3 are affixed underneath the lower surface of the front portion,
so they align with the cutouts in the metallic casing. Although
the casing is metal and the plates are plastic, both could be comprised
of plastic or both could be made of a variety of other materials.
As can be seen in FIG. 2 the electronic sign 1 has a front portion
4 a rear portion 6 and a down plate 8 forming the enclosure. A
battery pack 16 and a switch 10 are attached to the interior of
down plate 8. The switch 10 has button 12 and a LED 14 protruding
from the front of down plate 8.
FIG. 3 displays the layout of the electronics in rear portion 6
of electronic sign 1 with front portion 4 removed. Another plastic
plate 5 embossed with a legend such as the word "EXIT",
and another plastic plate 7 embossed with a chevron symbol, are
attached to the interior surface of rear portion 6. V-shaped walls
70 and 72 are disposed on both sides of the "EXIT" and
surrounding the chevron symbol. V-shaped walls 70 and 72 are provided
to increase the intensity of light illuminating the chevron symbol.
Brackets 30 32 34 36 are affixed in each corner of rear portion
6. Nylon buttons 46 48 50 52 protrude from the brackets for holding
LED units 42 and 44 on the inside of the brackets. Additionally,
a power unit 38 and a controller circuit 40 are mounted to the opposite
side of the bracket and being enclosed in their own casing 37 39.
Brackets 30 and 32 have a dual purpose, which is to hold LED unit
44 and to seal power unit 38 and control circuit 40 thus creating
a more compact design. Down plate 8 has a battery pack 16 and a
battery backup self test switch 10 affixed to the rear surface of
plate 8. Down plate 8 is releasably slidable into rear portion 6.
This provides a battery backup feature that can be an option to
the customer. This also allows for easy replacement of discharged
batteries. Battery pack 16 is comprised of five batteries 18 20
24 26 and 28 that provide enough current to illuminate the LEDs
on the LED units 42 44 for approximately 90 minutes. Power unit
38 is comprised of a transformer that converts AC voltage to DC
voltage. Normally power unit 38 provides current to the LEDs for
operation. However, in the event of an AC power failure control
circuit 40 senses the failure and relays the battery pack voltage
to the LEDs. Depressing and holding self-test switch 10 will also
perform this function. The power and time requirements may vary
depending on the particular application.
It should be appreciated that self test switch 10 is not limited
to a push button switch. Referring to FIGS. 6 and 7 rear portion
6 of the electronic sign includes a receiver box 70. Receiver box
70 includes all of the circuiting necessary for receiving and decoding
a radio frequency signal from a remote control unit 74. Preferably,
the remote control unit operates at a frequency of 300 megahertz.
Remote control unit 74 includes a test button 78 a reset button
80 and a test in progress LED 76. A user can press test button 78
on remote control unit 74 and transmit a signal through an antenna
77 to receiver box 70. The circuitry in receiver box 70 receives
the signal, decodes the signal and switches self test switch 10
from AC power to battery power. An LED 72 remains illuminated while
the device is powered by AC power and turns off when the device
is powered by battery power. Pressing reset button 80 sends a reset
signal to receiver box 70 and switches self test switch 10 from
battery power to AC power. Typically, the remote control unit has
a range of at least fifteen feet. The remote controller and the
receiver box combination allows for easy periodic checking of the
battery backup circuitry without the aid of a ladder. The radio
frequency transmitter and receiver arrangement could be
replaced by an infra-red transmitter and receiver.
Referring to FIGS. 4 and 5 LED units 42 and 44 are comprised of
a LED stick 60 and a vinyl LED enclosure 62. The LED sticks have
9 equally spaced LEDs, with eight on the front surface for lighting
the exit display, and a center LED on the rear surface for lighting
the chevron. It should be appreciated that the formation and number
of LEDs may vary depending on the amount of light needed to be generated
for a given application. Vinyl LED enclosure 62 and the LED stick
60 have apertures 64 and 66. This allows for affixing the LED units
to the brackets through the vinyl knobs. Using the vinyl knobs and
vinyl enclosures, allow for easy installation and replacement of
the LED units and are also very low in cost. The LED units protrude
from the brackets and are vertically centered in the enclosure.
This in combination with the spacing of the LEDs gives the exit
sign uniform illumination for both the word exit and the chevron
symbol. This design permits the same unit to drive either a single
or double face exit.
As can be seen from the description, this layout not only provides
the advantages previously stated, but is also easy to manufacture,
minimal in cost and easy to repair. This layout can apply to exit
signs of varying sizes. The only difference will be the size and
spacing of the LED units and the spacing of the brackets.
The foregoing description is a specific embodiment of the present
invention. It should be appreciated that this embodiment is described
for purposes of illustration only, and that numerous alterations
and modifications may be practiced by those skilled in the art without
departing from the spirit and scope of the invention. It is intended
that all such modifications and alterations be included insofar
as they come within the scope of the invention as claimed or the
equivalents thereof. |