Electronic display with cooling
View Patent ↗Display assemblies with thermal management features are provided. The display assemblies include an image assembly, a housing for the image assembly having an intake and exhaust. A first, continuous airflow pathway is located within the housing, and includes a first portion located forward of the image assembly and a second portion located rearward of the image assembly. A second airflow pathway extends within the housing between the intake and the exhaust. A heat exchanger located within the housing and rearward of the image assembly includes a first set of ducted passageways forming part of the first airflow pathway and a second set of ducted passageways forming part of the second airflow pathway. The first set of ducted passageways extend alongside, in an alternating fashion with, the second set of ducted passageways.
1. A display assembly with thermal management features, said display assembly comprising:
an image assembly;
a housing for the image assembly, comprising an intake and an exhaust;
a first, continuous airflow pathway located within the housing, having a first portion located forward of the image assembly and a second portion located rearward of the image assembly;
a second airflow pathway extending within the housing between the intake and the exhaust; and
a heat exchanger located within the housing and rearward of the image assembly, said heat exchanger comprising a first set of ducted passageways forming part of said first airflow pathway and a second set of ducted passageways forming part of said second airflow pathway, wherein said first set of ducted passageways extend alongside, in an alternating fashion with, the second set of ducted passageways.
2. The display assembly of claim 1 wherein:
the heat exchanger is a crossflow heat exchanger.
3. The display assembly of claim 1 wherein:
the heat exchanger is a parallel flow heat exchanger.
4. The display assembly of claim 1 wherein:
the heat exchanger is a counter flow heat exchanger.
5. The display assembly of claim 1 wherein:
each of the first set of ducted passageways are enclosed on at least four sides to provide a through channel for gas; and
each of the second set of ducted passageways are enclosed on at least four sides to provide a through channel for gas.
6. The display assembly of claim 1 wherein:
the second airflow pathway is sealed from an ambient environment in a manner sufficient to prevent contaminants above a certain size from entering the second airflow pathway, but which is less well sealed than a hermetic seal.
7. The display assembly of claim 6 further comprising:
electronic assemblies for operating the display assembly located within the second portion of the first airflow pathway and outside of the heat exchanger.
8. The display assembly of claim 7 further comprising:
a front display surface forming a part of the housing, wherein said front display surface is located forward of, and spaced apart from, a forward surface of the image assembly.
9. The display assembly of claim 8 wherein:
the first airflow pathway comprises a rear chamber located behind the image assembly and a channel located between an inner surface of the front display surface and the forward surface of the image assembly; and
the heat exchanger is located within a first part of the rear chamber, and the electronic assemblies are located at a second part of the rear chamber.
10. The display assembly of claim 9 further comprising:
a first set of fans located along the first airflow pathway for forcibly moving circulating gas through the first airflow pathway when activated, including periodically moving an entirety of said circulating gas within said channel through said rear chamber, including through said heat exchanger.
11. The display assembly of claim 9 wherein:
the electronic assemblies comprise:
a first group of electronic assemblies comprising relatively high power assemblies comprising one or more of: power modules, inductors, and transformers; and
a second group of electronic assemblies comprising relatively low power assemblies comprising one or more of: timing and control boards, hard drives and other storage devices, video cards, software drivers, and microprocessors.
12. The display assembly of claim 8 further comprising:
a polarizer provided at an inner surface of the front display surface.
13. The display assembly of claim 12 further comprising:
a second polarizer at the forward surface of said image assembly.
14. The display assembly of claim 12 wherein:
the front display surface comprises a plurality of transparent or translucent plates.
15. The display assembly of claim 1 further comprising:
a first set of one or more fans located along the first airflow pathway for forcibly moving circulating gas through the first airflow pathway when activated; and
a second set of one or more fans located along the second airflow pathway for forcibly moving ambient air through said second airflow pathway when activated.
16. The display assembly of claim 15 wherein:
the second set of one or more fans is configured to, when activated, draw relatively cool ambient air through the intake from an ambient environment, along the second airflow pathway, and out the exhaust to absorb heat from the image assembly and circulating gas in said second airflow pathway by way of the heat exchanger;
the first set of one or more fans is configured to, when activated, move said circulating gas across a viewing surface of said image assembly to pick up heat generated from the image assembly and solar loading at the image assembly and move the relatively warm circulating gas through the first airflow pathway to thermally disburse heat contained therein to the relatively cool ambient air in the first airflow pathway by way of the heat exchanger for exhaustion to the ambient environment; and
the first set of one or more fans and the second set of one or more fans are located rearward of the electronic display.
17. The display assembly of claim 16 wherein:
the first set of one or more fans are configured to, when activated, move a flow of the relatively warm circulating gas through each of the first set of ducted passageways such that a plurality of flows of the relatively warm circulating air are formed, and the second set of one or more fans are configured to, when activated, move a flow of the relatively cool ambient air through each of the second set of ducted passageways such that a plurality of flows of the relatively cool ambient air are formed; and
the plurality of flows of the relatively warm circulating gas alternate with the plurality of flows of the relatively cool ambient air to promote heat transfer from the relatively warm circulating gas to the relatively cool ambient air as the flows through the heat exchanger move past one another.
18. The display assembly of claim 1 wherein:
a portion of the second airflow pathway extends along a rear surface of the image assembly.
19. The display assembly of claim 18 wherein:
the portion of the second airflow pathway extends directly along the rear surface of the image assembly with no intervening airflow pathways.
20. The display assembly of claim 19 wherein:
the rear surface of the image assembly comprises a thermally conductive material.
21. The display assembly of claim 20 wherein:
the image assembly comprises a liquid crystal display (LCD) stack and a backlight assembly for the LCD stack; and
the rear surface of the image assembly is a rear surface of the backlight assembly.
22. The display assembly of claim 1 wherein:
the first set of ducted passageways comprises a plurality of ducted passageways; and
the second set of ducted passageways comprises a plurality of ducted passageways.
23. The display assembly of claim 22 wherein:
each of the plurality of ducted passageways in the first set of ducted passageways is adjacent to at least one of the plurality of ducted passageways in the second set of ducted passageways.
24. The display assembly of claim 22 wherein:
a single panel separates each of the first set of ducted passageways from a respective one of the second set of ducted passageways.
25. A display assembly with thermal management features, said display assembly comprising:
an image assembly comprising a liquid crystal display (LCD) stack and a backlight assembly for the LCD stack;
a housing for the image assembly comprising an intake and an exhaust, where said intake and said exhaust are fluidly connected to an ambient environment;
a front display surface forming part of the housing, where said front display surface is located forward of, and spaced part from, a forward surface of said image assembly;
a first airflow pathway located within the housing and forming a continuous pathway for circulating gas within the housing including a channel located between the forward surface of the image assembly and an interior surface of the front display surface and a rear chamber located behind the image assembly;
a second airflow pathway comprising a continuous passageway extending through the housing between the intake and the exhaust; and
a heat exchanger located within the housing rearward of the image assembly, said heat exchanger comprising ducted passageways, a first subset of which form part of said first airflow pathway and a second subset of which form part of said second airflow pathway, wherein ducted passageways forming part of the first airflow pathway extend alongside, and alternate with, the ducted passageways forming part of the second airflow pathway, each of said first and second subsets of the ducted passageways comprising multiple of the ducted passageways;
wherein each of the ducted passageways in the first subset and in the second subset are enclosed on at least four sides to form a through channel;
wherein the first airflow pathway is fluidly separated from the second airflow pathway in a manner sufficient to prevent contaminates in ambient air within the second airflow pathway from crossing over into, and contaminating, the circulating gas in the first airflow pathway, but where such fluid separation is less secured than a hermetic seal.
26. The display assembly of claim 25 :
further comprising:
a first set of one or more fans located along the first airflow pathway for forcibly moving circulating gas through the first airflow pathway when activated; and
a second set of one or more fans located along the second airflow pathway for forcibly moving ambient air through said second airflow pathway when activated;
wherein:
the second set of one or more fans is configured to, when activated, draw relatively cool ambient air through the intake from an ambient environment, along the second airflow pathway, and out the exhaust to absorb heat from the image assembly and circulating gas in said second airflow pathway by way of the heat exchanger;
the first set of one or more fans is configured to, when activated, move said circulating gas across a viewing surface of said image assembly to pick up heat generated from the image assembly and solar loading at the image assembly and move the relatively warm circulating gas through the first airflow pathway to thermally disburse heat contained therein to the relatively cool ambient air in the first airflow pathway by way of the heat exchanger for exhaustion to the ambient environment; and
the first set of one or more fans and the second set of one or more fans are located rearward of the electronic display.
27. The display assembly of claim 26 wherein:
the first set of one or more fans are configured to, when activated, move a flow of the relatively warm circulating gas through each of the ducted passageways in the first subset such that a plurality of flows of the relatively warm circulating air are formed, and the second set of one or more fans are configured to, when activated, move a flow of the relatively cool ambient air through each of the ducted passageways in the second subset such that a plurality of flows of the relatively cool ambient air are formed; and
the plurality of flows of the relatively warm circulating gas alternate with the plurality of flows of the relatively cool ambient air to promote heat transfer from the relatively warm circulating gas to the relatively cool ambient air as the flows through the heat exchanger move past one another.
28. A display assembly with thermal management features, said display assembly comprising:
an image assembly comprising a polarizer layer, a liquid crystal layer located rearward of the polarizer layer, and a backlight assembly comprising a plurality of light emitting diodes arranged to, when activated, directly backlight the liquid crystal layer;
a housing for the image assembly;
a first airflow pathway located within the housing and forming a continuous pathway for circulating gas and located forward and rearward of the image assembly;
a second airflow pathway extending within the housing between an intake and an exhaust such that said second airflow pathway is fluidly connected to an ambient environment;
at least one fan located along the first airflow pathway;
at least one fan located along the second airflow pathway;
a heat exchanger located within the housing rearward of the image assembly, said heat exchanger comprising a first set of multiple ducted passageways forming part of said first airflow pathway which are enclosed on at least four sides to form a through channel for the circulating gas to pass through and a second set of multiple ducted passageways forming part of said second airflow pathway which are enclosed on at least four sides to form a through channel for ambient air to pass through, wherein said first and second set of multiple ducted passageways extend alongside one another in an alternating fashion; and
electronic assemblies for operating the display assembly located within a portion of the first airflow pathway located rearward of the image assembly and outside of the heat exchanger, wherein the first airflow pathway is fluidly sealed from the ambient environment and the second airflow pathway at a level less well sealed than a hermetic seal but sufficient to prevent particulate above a certain size from entering the first airflow pathway from the ambient environment and the second airflow pathway.
29. The display assembly of claim 28 wherein:
the at least one fan located along the second airflow pathway is configured to, when activated, draw relatively cool ambient air through the intake from an ambient environment, along the second airflow pathway, and out the exhaust to absorb heat from the image assembly and circulating gas in said second airflow pathway by way of the heat exchanger;
the at least one fan located along the first airflow pathway is configured to, when activated, move said circulating gas across a viewing surface of said image assembly to pick up heat generated from the image assembly and solar loading at the image assembly and move the relatively warm circulating gas through the first airflow pathway to thermally disburse heat contained therein to the relatively cool ambient air in the first airflow pathway by way of the heat exchanger for exhaustion to the ambient environment;
the at least one fan located along the second airflow pathway and the at least one fan located along the first airflow pathway are located rearward of the electronic display;
the at least one fan located along the first airflow pathway is configured to, when activated, move a flow of the relatively warm circulating gas through each of the first set of the ducted passageways such that a plurality of flows of the relatively warm circulating air are formed, and the at least one fan located along the second airflow pathway is configured to, when activated, move a flow of the relatively cool ambient air through each of the second set of the ducted passageways such that a plurality of flows of the relatively cool ambient air are formed; and
the plurality of flows of the relatively warm circulating gas alternate with the plurality of flows of the relatively cool ambient air to promote heat transfer from the relatively warm circulating gas to the relatively cool ambient air as the flows through the heat exchanger move past one another.