U.S. patent application number 12/235200 was filed with the patent office on 2009-05-21 for isolated gas heating system for an electronic display.
This patent application is currently assigned to MANUFACTURING RESOURCES INTERNATIONAL, INC.. Invention is credited to William DUNN.
Application Number | 20090126907 12/235200 |
Document ID | / |
Family ID | 40640713 |
Filed Date | 2009-05-21 |
United States Patent
Application |
20090126907 |
Kind Code |
A1 |
DUNN; William |
May 21, 2009 |
Isolated Gas Heating System for an Electronic Display
Abstract
A preferred embodiment relates to a heating system and a method
for heating an electronic display. A preferred embodiment includes
a transparent gas heat-transfer chamber which may be coexistent
with the viewable display surface. The heating system defines two
gas compartments that are anterior and posterior to the electronic
display and are in gaseous communication. Fans may be used to
propel the isolated gas through the two chambers. The circulating
gas transfers heat to the electronic display surface by convection.
The isolated gas is preferably transparent or at least
semi-transparent.
Inventors: |
DUNN; William; (Alpharetta,
GA) |
Correspondence
Address: |
STANDLEY LAW GROUP LLP
6300 Riverside Drive
Dublin
OH
43017
US
|
Assignee: |
MANUFACTURING RESOURCES
INTERNATIONAL, INC.
Alpharetta
GA
|
Family ID: |
40640713 |
Appl. No.: |
12/235200 |
Filed: |
September 22, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12234360 |
Sep 19, 2008 |
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12235200 |
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12234307 |
Sep 19, 2008 |
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12234360 |
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11941728 |
Nov 16, 2007 |
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12234307 |
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12191384 |
Aug 14, 2008 |
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11941728 |
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61076126 |
Jun 26, 2008 |
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61039454 |
Mar 26, 2008 |
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61057599 |
May 30, 2008 |
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Current U.S.
Class: |
165/104.31 |
Current CPC
Class: |
H05K 7/20972
20130101 |
Class at
Publication: |
165/104.31 |
International
Class: |
F28D 15/00 20060101
F28D015/00 |
Claims
1. A heating system for an electronic display having a display
surface, the system comprising: a first gas chamber positioned
anterior to the electronic display surface; a second gas chamber in
gaseous communication with said first gas chamber; a heating
chamber fan within said second gas chamber to propel gas around the
first and second gas chambers; and means for heating the gas
contained within the second gas chamber.
2. The system of claim 1, wherein: the first gas chamber comprises
a transparent anterior plate; and the second gas chamber comprises
a heating plenum.
3. The system of claim 2, wherein the first gas chamber further
comprises the electronic display surface; spacers separating the
electronic display surface and said transparent anterior plate; and
an entrance opening and an exit opening.
4. The system of claim 3, wherein: the first gas chamber further
comprises a second transparent anterior plate bonded to the first
transparent anterior plate.
5. The system of claim 2, wherein: the first gas chamber is adapted
to transfer heat from the gas to the display surface.
6. The system of claim 2, wherein the means for heating the gas
comprises heating elements.
7. The system of claim 1, wherein the means for heating the gas
comprises electrical components.
8. The system of claim 1, further comprising: a temperature sensing
device within said first gas chamber; a switch in communication
with said temperature sensing device and said heating chamber fan;
and wherein the fan is switched on when the temperature within the
first gas chamber reaches a threshold value.
9. The system of claim 6 wherein the plenum is thermally
insulated.
10. The system of claim 1 wherein said fan runs continuously when
the display is in operation.
11. The system of claim 1 further comprising a filter within the
second gas chamber.
12. A heating system for an electronic display having a display
surface, said system comprising: a first gas chamber comprising the
display surface of the electronic display; a transparent anterior
plate separated from said display surface by spacers; and an
entrance and exit opening; and a second gas chamber in gaseous
communication with said first gas chamber, said second gas chamber
comprising a heating plenum; a heating chamber fan to propel gas
around the first and second gas chambers; and one or more heating
elements.
13. The system from claim 12 further comprising one or more
electrical components within the heating plenum.
14. The system from claim 12 further comprising a filter within
said second gas chamber.
15. The system from claim 12 further comprising: a temperature
sensing device within said first gas chamber; a switch in
communication with said temperature sensing device and said heating
chamber fan; and wherein the fan is switched on when the
temperature within the first gas chamber reaches a threshold
value.
16. A method for heating an electronic display having a display
surface with isolated gas, comprising the steps of: providing an
isolated gas system comprising a first gas chamber which is in
contact with the electronic display surface and a second gas
chamber comprising a heating plenum, wherein the first and second
gas chambers are in gaseous communication; forcing isolated gas
into the first gas chamber; transferring heat from the isolated gas
to the electronic display surface; directing the isolated gas into
the heating plenum; heating the isolated gas in the plenum; and
reintroducing the heated isolated gas into the first gas
chamber.
17. The method of claim 16, wherein the heating step comprises the
steps of: providing one or more heating elements within said
heating plenum; forcing the isolated gas over said one or more
heating elements; and transferring heat from the heating elements
to the isolated gas.
18. The method of claim 16, further comprising the steps of:
setting a threshold temperature for the isolated gas; measuring the
temperature of the isolated gas; comparing the temperature of the
isolated gas to the threshold temperature; and heating the isolated
gas only when the temperature of the isolated gas is less than the
threshold temperature.
19. The method of claim 16, further comprising the step of
filtering the isolated gas prior to forcing it into the first
chamber.
20. The method of claim 16, further comprising the step of
preventing a substantial amount of heat from escaping the second
gas chamber.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a non-provisional patent application and
claims priority to U.S. Provisional Application No. 61/076,126
filed Jun. 26, 2008; 61/057,599 filed May 30, 2008; and 61/039,454
filed Mar. 26, 2008, which are hereby incorporated by reference in
their entirety. This application is also a continuation in part of
U.S. patent application Ser. No. 11/941,728 filed Nov. 16, 2007,
which is hereby incorporated by reference in its entirety. This
application is also a continuation in part of U.S. patent
application Ser. No. 12/191,834 filed Aug. 14, 2008, which is
hereby incorporated by reference in its entirety. This application
is also a continuation in part of U.S. patent application Ser. No.
12/234,307 filed Sep. 19, 2008, which is hereby incorporated by
reference in its entirety. This application is also a continuation
in part of U.S. patent application Ser. No. 12/234,360 filed Sep.
19, 2008.
TECHNICAL FIELD
[0002] This invention generally relates to heating systems and in
particular to a heating system and method for electronic
displays.
BACKGROUND OF THE ART
[0003] In a typical electronic display, heat transfer systems
typically seek to remove heat from the display. This may be done in
any number of ways, but usually these systems generally attempt to
remove heat from the electronic components in a display through
sidewalls of the display housing.
[0004] When typical displays experience low temperatures, the heat
transfer system is not adapted to maintain the heat of the display,
or perhaps generate additional heat. This may be necessary, as low
temperatures can cause a display to malfunction, not display images
properly, or may permanently damage the display. Specifically for
liquid crystal displays (LCDs), the crystal material may
malfunction once the display experiences low temperatures. They
crystal material may not respond appropriately to a potential
difference and, in some cases, the crystal material may even
freeze. Furthermore, although there may be some heat near the back
of the display where the electrical components are, this heat has
no way of contacting the area near the crystal material and thus
heating the crystals.
SUMMARY OF THE INVENTION
[0005] Exemplary embodiments relate to an isolated gas heating
system and a method for heating an electronic display. An exemplary
embodiment includes an isolated gas heating chamber. The gas
heating chamber is preferably a closed loop which includes a first
gas chamber comprising a transparent anterior plate and a second
gas chamber comprising a heating plenum. The first gas chamber is
anterior to and coextensive with the viewable face of the
electronic display surface. The transparent anterior plate may be
set forward of the electronic display surface by spacers defining
the depth of the first gas chamber.
[0006] A heating chamber fan, or equivalent means, may be located
within the heating plenum. The fan may be used to propel gas around
the isolated gas heating chamber loop. As the gas traverses the
first gas chamber it contacts the electronic display surface,
transferring heat to the front surface of the display. Because the
gas and the relevant surfaces of the first gas chamber are
transparent, the image quality remains excellent. After the gas has
traversed the transparent first gas chamber, the gas may be
directed into the rear heating plenum. In order to heat the gas in
the plenum, heating elements may be used. In other embodiments,
electronic components which operate the display may be placed
within the heating plenum. These components naturally generate heat
during operation, and can further heat the gas within the heating
plenum. These components will also run more efficiently, if cool
air is regularly circulated over them.
[0007] The foregoing and other features and advantages of the
present invention will be apparent from the following more detailed
description of the particular embodiments of the invention, as
illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] A better understanding of an exemplary embodiment will be
obtained from a reading of the following detailed description and
the accompanying drawings wherein identical reference characters
refer to identical parts and in which:
[0009] FIG. 1 is a perspective view of an exemplary embodiment in
conjunction with an exemplary electronic display.
[0010] FIG. 2 is an exploded perspective view of an exemplary
embodiment showing components of the isolated gas heating
system.
[0011] FIG. 3 is top plan view of an exemplary embodiment of the
heating chamber.
[0012] FIG. 4 is a front perspective view of an embodiment of the
isolated heating chamber, particularly the transparent anterior
surface of first gas chamber.
[0013] FIG. 5 is a rear perspective view of an embodiment of the
isolated heating chamber, particularly the heating plenum.
[0014] FIG. 6 is a schematic of several embodiments for heating
elements.
DETAILED DESCRIPTION
[0015] Exemplary embodiments provide an isolated gas heating system
for an electronic display.
[0016] FIG. 1 is an exemplary embodiment of the present invention.
As may be appreciated, when the display 10 is exposed to cold
temperatures and/or wind, the temperatures inside the display 10
will vary greatly without some kind of heating device, and may even
drop below freezing. As such, the electronics including the display
screen (e.g., LCD screen) may not function properly and may have a
greatly reduced life span. By implementing certain embodiments of
the heating system disclosed herein, temperature fluctuation is
greatly reduced.
[0017] The display shown is equipped with an innovative gas heating
system. Accordingly, it may be placed in environments which may
experience low temperatures. Although the heating system may be
used on any type of electronic display, it is especially useful for
LCD displays.
[0018] In FIG. 1, the display area of the electronic display shown
includes a narrow gas chamber that is anterior to and coextensive
with the electronic display surface. Optionally, the display also
may have a reflection shield 119, to mitigate reflection of any
sunlight on the display surface. Additionally, if the display
experiences very cold temperatures, especially in outdoor
environments, housing 70 may be a color which absorbs sunlight.
[0019] It is to be understood that the spirit and scope of the
disclosed embodiments includes heating of displays including, but
not limited to LCDs. By way of example and not by way of
limitation, the present invention may be used in conjunction with
displays selected from among LCD (including TFT or STN type), light
emitting diode (LED), organic light emitting diode (OLED), field
emitting display (FED), cathode ray tube (CRT), and plasma
displays. Furthermore, embodiments of the present invention may be
used with displays of other types including those not yet
discovered. In particular, it is contemplated that the present
invention may be well suited for use with full color, flat panel
OLED displays. While the embodiments described herein are well
suited for outdoor environments, they may also be appropriate for
indoor applications (e.g., factory environments, coolers, freezers,
frozen food processing plants) where thermal stability of the
display may be at risk.
[0020] As shown in FIG. 2 an exemplary embodiment 10 of the
electronic display and gas heating system includes an isolated gas
heating chamber 20 contained within an electronic display housing
70. A narrow transparent first gas chamber is defined by spacers
100 and transparent front plate 90. A second transparent front
plate 130 may be laminated to front plate 90 to help prevent
breakage of front plate 90. If used with a LCD display, heating
chamber 20 surrounds the LCD stack 80.
[0021] Referring to FIG. 3, in at least one embodiment the isolated
gas heating chamber 20 comprises a closed loop which includes a
first gas chamber 30 and a second gas chamber 40. The first gas
chamber includes a transparent plate 90. The second gas chamber
comprises a heating plenum 45. The term "isolated gas" refers to
the fact that the gas within the isolated gas heating chamber 20 is
essentially isolated from external air in the housing of the
display. Because the first gas chamber 30 is positioned in front of
the display image, the gas should be substantially free of dust or
other contaminates that might negatively affect the display image.
An optional air filter (not shown) may be employed within the
plenum to assist in preventing contaminates and dust from entering
the first gas chamber 30.
[0022] The isolated gas may be almost any transparent gas, for
example, normal air, nitrogen, helium, or any other transparent
gas. The gas is preferably colorless so as not to affect the image
quality. Furthermore, the isolated gas heating chamber need not
necessarily be hermetically sealed from the external air. It is
sufficient that the gas in the chamber is isolated to the extent
that dust and contaminates may not substantially enter the first
gas chamber.
[0023] In the closed loop configuration shown in FIG. 3, the first
gas chamber 30 is in gaseous communication with the second gas
chamber 40. A heating chamber fan 50 may be provided within the
posterior plenum 45. The heating fan 50 may be utilized to propel
gas around the isolated gas heating chamber 20. The first gas
chamber 30 includes at least one front glass 90 mounted in front of
an electronic display surface 85. In an exemplary embodiment, the
electronic display surface 85 may be adjacent to a LCD stack so
that heat can easily transfer to the liquid crystal material.
Optionally, the electronic display surface 85 may be the front
portion of the LCD stack.
[0024] Referring now to FIG. 4, the front plate 90 may be set
forward from the electronic display surface 85 by spacers 100. The
spacing members 100 define the depth of the narrow channel passing
in front of the electronic display surface 85. The spacing members
100 may be independent or alternatively may be integral with some
other component of the device (e.g., integral with the front
plate). The electronic display surface 85, the spacing members 100,
and the transparent front plate 90 define a narrow first gas
chamber 30. The chamber 30 is in gaseous communication with plenum
45 through entrance opening 110 and exit opening 120.
[0025] The posterior surface of the first gas chamber 30 preferably
comprises the electronic display surface 85 of the display stack
80. As the isolated gas in the first gas chamber 30 traverses the
display it contacts the electronic display surface 85. Contacting
the heating gas directly to the electronic display surface 85
allows heat to transfer to the electronic display surface 85, and
subsequently to the display stack 80. Accordingly, the term
"electronic display surface" may refer to the front surface of a
typical electronic display (in the absence of the embodiments
disclosed herein). The term "viewable surface" or "viewing surface"
refers to that portion of the electronic display surface from which
the electronic display images may be viewed by the user.
[0026] The electronic display surface 85 of typical displays is
glass. However, neither display surface 85, nor transparent front
plate 90, nor optional second transparent front plate 130 need
necessarily be glass. Therefore, the term "glass" will be used
herein interchangeably with the term plate. By utilizing the
electronic display surface 85 as the posterior surface wall of the
gas compartment 30, there may be fewer surfaces to impact the
visible light traveling through the display. Furthermore, the
device will be lighter and cheaper to manufacturer.
[0027] Although the embodiment shown utilizes the electronic
display surface 85, certain modifications and/or coatings (e.g.,
anti-reflective coatings) may be added to the electronic display
surface 85, or to other components of the system in order to
accommodate the heating gas or to improve the optical performance
of the device. In the embodiment shown, the electronic display
surface 85 may be the front glass plate of a liquid crystal display
(LCD) stack or the front plate of a plasma display or the front
plate of an OLED display. However, almost any display surface may
be suitable for embodiments of the present heating system. Although
not required, it is preferable to allow the heating gas in the
first gas chamber 30 to contact the electronic display surface 85
directly. In this way, the convective effect of the circulating gas
will be maximized. Preferably the gas, which has transferred heat
to the electronic display surface 85 may then be diverted to the
heating plenum 45 where it may absorb heat.
[0028] To prevent breakage, the optional second surface glass 130
may be adhered to the front surface of plate 90. Also, surface
glass 130 may be heat tempered to improve its strength and may be
coated with a polarizer. As shown in FIG. 3, fan 50 propels a
current of air around the loop (see arrows) of the isolated gas
heating chamber 20.
[0029] The plenum 45 defining the second gas chamber 40 is adapted
to circulate the gas behind the electronic display assembly.
Heating elements 200 may be located within the second gas chamber
40 and operate to warm the gas as it passes through the second gas
chamber 40. These heating elements can be any one of the many
commonly available heating elements. Many times, these elements are
simply a material which contains a high electrical resistance, and
thus generates heat when current flows through it. The heating
elements can be, but are not limited to, any one of the following:
nichrome wire or ribbon, screen printed metal/ceramic tracks
deposited on ceramic insulated metal (generally steel) plates,
CalRod (typically a fine coil of nichrome wire in a ceramic binder,
sealed inside a tough metal shell), heat lamp, and Positive Thermal
Coefficient (PTC) of resistance ceramic.
[0030] Additionally, the plenum 45 may contain electrical
components 210 which power and control the electronic display. The
electrical components may be any one of the following:
transformers, microprocessors, printed circuit boards, resistors,
capacitors, motors, wiring harnesses, and connectors. The
electrical connections for the electrical components 210 may pass
through a wall of the plenum 45. The electrical components 210 can
be located anywhere within the plenum 45. The electrical components
210 may be mounted on the posterior or anterior surface of the
plenum and may be mounted directly on the surface of the plenum or
may be suspended by mounting posts so that gas may pass all around
the component.
[0031] FIG. 4 shows that the anterior surface 90 of the first gas
chamber 30 is transparent and is positioned anterior to and at
least coextensive with a viewable area of an electronic display
surface 85. The arrows shown represent the movement of the isolated
gas through the first gas chamber 30. As shown, the isolated gas
traverses the first gas chamber 30 in a generally horizontal
direction. Although heating system 20 may be designed to move the
gas in either a horizontal or a vertical direction, it is
preferable to propel the gas in a horizontal direction. In this
way, if dust or contaminates do enter the first gas chamber 30,
they will tend to fall to the bottom of chamber 30 outside of the
viewable area of the display. The system may move air left to
right, or alternatively, right to left.
[0032] As is clear from FIG. 4, to maximize the heating capability
of the system, the first gas chamber 30 preferably covers the
entire viewable surface of the electronic display surface 85.
Because the relevant surfaces of the first gas chamber 30 as well
as the gas contained therein are transparent, the image quality of
the display remains excellent. Anti-reflective coatings may be
utilized to minimize specular and diffuse reflectance. After the
gas traverses the first gas chamber 30 it exits through exit
opening 120. Exit opening 120 defines the entrance junction into
the rear heating plenum 45.
[0033] FIG. 5 shows a schematic of the rear heating plenum 45
(illustrated as transparent for explanation). One or more fans 50
within the plenum may provide the force necessary to move the
isolated gas through the isolated gas heating chamber. Whereas the
first gas chamber 30 was designed to transfer heat from the gas to
the front surface 85 of the display, the second gas chamber 40 is
designed for the gas to absorb heat from either the heating
elements 200, the electrical components 210, or both. Plenum 45 may
have various contours and features to accommodate the internal
structures within a given electronic display application.
[0034] It should be noted that two different types of heating
elements are shown in the figures. However, a single type of
heating element could be used in an exemplary embodiment.
Alternatively, a combination of different types of heating elements
could be used. Again, the specific type of heating element is
entirely dependent upon the specific application, costs, size of
the display, and surrounding environment. Several different types
of CalRod heating elements are shown in FIG. 6. Obviously, these
types of heating elements can take on almost any shape, and the
designs which are shown are only exemplary and are not
exhaustive.
[0035] In some embodiments, it may be advantageous to insulate the
plenum walls, so that heat from the warm gas may not escape into
the surrounding environment. This may be useful in situations where
the temperature remains relatively cold throughout the operative
life of the device, or perhaps when the display must temporarily
experience very cold temperatures.
[0036] Furthermore, some electronic displays may be required to
operate in a broad range of temperatures, i.e. from very hot to
very cold. These displays may utilize both the heating system which
is herein disclosed, as well as the cooling system disclosed in
Co-pending application Nos. 61/033,064, Ser. No. 12/191,834,
61/053,713, 61/057,599, and 61/039,454. These embodiments may also
contain the optional air curtain device, described in Co-pending
application Ser. No. 11/941,728.
[0037] In some applications, the isolated gas heating system may
run continuously while the display is operational. However, if
desired, a temperature sensor (not shown) and a switch (not shown)
may be incorporated. This thermostat may be used to detect when
temperatures have reached a predetermined threshold value. In such
a case, the isolated gas heating system may be selectively engaged
when the temperature in the display reaches a predetermined value.
Predetermined thresholds may be selected and the system may be kept
within an acceptable temperature range.
[0038] Having shown and described preferred embodiments, those
skilled in the art will realize that many variations and
modifications may be made to affect the described embodiments and
still be within the scope of the claimed invention. Additionally,
many of the elements indicated above may be altered or replaced by
different elements which will provide the same result and fall
within the spirit of the exemplary embodiments. It is the
intention, therefore, to limit the invention only as indicated by
the scope of the claims.
* * * * *