The present invention relates generally to structures for enclosing display devices. More particularly, the present invention relates to enclosures for heating and/or cooling display devices and/or the interior of the display enclosure.
This section is intended to provide a background or context to the invention that is recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
In recent years, flat panel televisions have become enormously popular in both commercial and residential sectors. As the prices for plasma and liquid crystal display (LCD) flat panel displays have continued to fall, and the quality for the same devices have improved, more and more businesses and individuals have purchased such devices for both home and business purposes.
The advantages of flat panel displays has also led to expanded application and placement of display devices, including locating display devices in new and challenging and environments. For example, display devices might be located outdoors in various residential and commercial settings for entertainment or marketing purposes, potentially exposing the display device to damaging rain, snow, debris, and other elements. Display devices might also be located in indoor environments such as restrooms, kitchens, and industrial settings for various entertainment, marketing, and informational purposes. As with outdoor applications, liquids and other potential contaminants may be near or come into contact with the mounted display device, potentially damaging or degrading the performance of the display device. It is desirable to protect the display device, which is often quite expensive, from exposure to environmental and other potential contaminants. Accordingly, various environmental enclosures have been developed that are intended to protect a display device from the elements and other containments to permit locating such displays outdoors and in other potentially inhospitable environments.
When the display device is within the environmental enclosure, the temperature within the enclosure may vary depending on the environment. For example, in an outdoor environment with cold temperatures, the interior temperature within the enclosure may be similarly cold, which may affect the operation of the display device (e.g, dimming the screen of the display device, freezing a liquid crystal display, etc.). Similarly, in an outdoor environment with hot temperatures, the interior temperature within the enclosure may be similarly hot, which may affect the operation of the display device (e.g., overheating electronics components within the display device, etc.).
Various embodiments comprise enclosed display device systems with a heating and/or cooling system for display devices such as a CRT, DLP, LCD, LED or plasma display device. In some implementations, these enclosure systems having a heating and/or cooling system may be used for CRT, DLP, or other non-low profile display devices. The various enclosure systems are substantially sealed and weatherproofed, thereby preventing ingress of liquids, such as precipitation, that may occur at an outdoor viewing location. The enclosure systems according to various embodiments provide a heating and/or cooling system for thermal management of the interior of the display enclosure system and of the enclosed display device. Modern flat panel display devices typically generate heat while in use. In some instances, the heat load generated can be substantial under various circumstances. Consequently, the temperature within an enclosure can rapidly rise above the thermal operating range of the display device unless mitigated. Thermal conditions within the enclosure may be exasperated by ambient conditions, for example, high ambient temperatures and/or a high solar load on the display enclosure. Additionally, under low ambient temperatures it may be necessary to generate additional heat within the enclosure when the display device is on or off in order to protect the display device and/or maintain sufficient operating temperature within the enclosure. Accordingly, the enclosure systems may include a thermoelectric heating and/or cooling module to control the temperature within the enclosure.
In one set of embodiments, a display enclosure with a temperature control system main include a display enclosure having an interior. The interior is sized and configured to receive a display device therein. The display enclosure also includes a thermoelectric module having a first portion and a second portion. The first portion is positioned within the interior of the display enclosure. The second portion is coupled to a portion of the display enclosure exposed to an external environment. The display enclosure further includes a thermal controller electrically coupled to the thermoelectric module and operable to control heating or cooling of the first portion of the thermoelectric module.
In another set of embodiments, a display enclosure with a temperature control system includes a display enclosure having an interior sized and configured to receive a display device therein. The display enclosure includes a thermoelectric module having a first portion and a second portion. The first portion is positioned within the interior of the display enclosure and the second portion is coupled to a portion of the display enclosure exposed to an outdoor environment. The display enclosure also includes a temperature sensor positioned within the interior of the display enclosure. The display enclosure further includes a thermal controller electrically coupled to the thermoelectric module and the temperature sensor. The thermal controller is operable to receive a first signal indicative of a temperature of the interior of the display enclosure output from the temperature sensor. The thermal controller further being operable to control heating or cooling of the first portion of the thermoelectric module based, at least in part, on the first signal output from the temperature sensor.
In yet another set of embodiments, a method for controlling the internal temperature of a display enclosure includes receiving, at a thermal controller of a display enclosure, a first signal indicative of a temperature of an interior of the display enclosure. The method includes determining whether the first signal indicative of the temperature of the interior of the display enclosure is above a first temperature set point and activating a thermoelectric module to cool the interior of the display enclosure if the first signal indicative of the temperature of the interior of the display enclosure is above the first temperature set point. The method further includes deactivating the thermoelectric module when the first signal indicative of the temperature of the interior of the display enclosure is below the first temperature set point.
These and other features, together with the organization and manner of operation thereof, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like elements have like numerals throughout the several drawings described below.
The display enclosure 10 is constructed so that the display device 20 may be located in an outdoor viewing environment or in other environments where the display device 20 requires or may benefit from protection from ambient conditions. Accordingly, the display enclosure 10 is constructed to resist and substantially prevent ingress of various liquids that may be encountered in the viewing location, including precipitation when the display enclosure 10 is mounted for outdoor viewing of the display device 20. In various embodiments, the display enclosure 10 is constructed to prevent ingress of rain, snow and splashing liquid. In a particular embodiment, the display enclosure 10 is constructed to prevent ingress of liquid at a submersed depth of up to five feet of water, which may correspond to a modified rating of the IP68 standard (the contents of which are incorporated herein by reference).
As described in greater detail below, the display enclosure 10 may be provided with features that enable or enhance performance and operation under various ambient conditions, while protecting the display device 20 from adverse conditions, such as liquids that may come into contact with the display enclosure 10 or varying ambient temperatures. The bezel 100, for example, may be constructed to provide the display enclosure 10 with a narrow periphery, or a low profile, that closely surrounds the display opening 111 through which the display area of the display device 20 is visible. Thus, the outer periphery of the bezel 100 defines an area and the display opening 111 defines a display opening area. In this configuration, the distance between an inner edge of the bezel 100 and the periphery of the bezel 100, the bezel thickness, is minimized. In a particular embodiment, the bezel thickness is less than about 50 mm, and in a further embodiment, the bezel thickness is less than about 25 mm. In further embodiments, the bezel thickness may fall between about 25 mm and about 50 mm.
The low profile of the bezel 100 permits the display area of the display device 20 to closely approach the periphery of the bezel 100. For example, the display opening area is maximized relative to the enclosure area. In a particular embodiment, the display opening area is at least about 85 percent of the enclosure area, and in another embodiment, the display area opening is at least about 92 percent of the enclosure area. In further embodiments, the display area opening may fall between about 85 percent and about 92 percent of the enclosure area. The above described configurations offer a clean, low profile look where the edge of the display area of the display device 20 is in proximity of the periphery of the display enclosure 10. These configurations permit, for example, a plurality of enclosures 10, each with a display device 20, to be arranged in a video wall such that the respective display devices 20 are in close proximity to one another, thereby enhancing the presentation of the image or images displayed on the display devices 20.
The display enclosure 10 may also include a heating and/or cooling system for thermal management of the internal temperature. Such a heating and/or cooling system may be an active system that controls the temperature within the display enclosure 10 and in maintaining an internal temperature that is within an operating range of the display device 20. Referring briefly to
In some embodiments, the first portion 610 of the thermoelectric module or modules 600 may be aligned with a portion of the display device 20 that is thermally sensitive or otherwise may benefit from thermal management. For example, the first portion 610 may be positioned within the display enclosure 10 such that the first portion 610 is substantially aligned with a location for a power supply module of the display device 20 and/or of the display enclosure 10, such as power supply 500. In other examples, the first portion 610 may be positioned such that the first portion 610 is substantially aligned with the display device 20 at other locations (e.g., near a TV tuner circuit, audio components, a processor or processing module, a computer-readable storage device, etc.) and/or other components of the display enclosure 10. In still other embodiments, the thermoelectric module or modules 600 and the first portion 610 may be arbitrarily positioned within the display enclosure 10.
In some embodiments, the second portion 620 of each thermoelectric module or modules 600 may be coupled to a rear cover assembly 300 for heat transfer to the heat sink portion of the rear cover assembly 300. For example, the thermoelectric module 600 and the rear cover assembly 300 may be coupled together (e.g., via connecting elements such as bolts, screws, latches, clamps, clips, etc. via adhesives, or otherwise) and may include a thermally conductive grease or adhesive interposed between the second portion 620 and the heat sink portion, as will be discussed in further detail in reference to
The display enclosure 10 may further include various additional features that, for example, sense ambient light conditions and communicate with the display device 20 to adjust the brightness of the display to enhance viewability of the display device 20 under various light conditions.
As shown in
As depicted in
Once the frame members 105 are joined to form the perimeter of the bezel 100, the bezel 100 may undergo an additional treatment or plurality of treatments. These treatments can include, for example, applying an organic coating and/or sealant to the bezel 100, which may be utilized to enhance resistance to environmental effects, strengthen the bezel, and/or provide a decorative coating. Various treatments can include polyurea coatings, urethane coatings, polyurethane coatings, epoxy coatings, powder coating, painting, anodizing, and combinations thereof. The material utilized in a particular treatment may be characterized as being adherable to the bezel 100 or an intermediate material disposed on the bezel and durable under various environmental conditions. Additionally, it may be desirable for the treatment to be characterized by one or more cosmetic attributes such as an ability to conceal surface imperfections in the bezel 100, including seams between the frame members 105, as well as providing a color, texture, and finish suitable for an outdoor display enclosure.
In an embodiment, the bezel 100 is treated with a polyurea coating. The polyurea coating may be applied as a liquid to portions of the bezel 100, such as the external surfaces or selected surfaces, or may be applied to the entire bezel 100. Selected surfaces of the bezel 100 may be coated by masking or other techniques. Application of the polyurea coating may be accomplished by a spray process. In various embodiments, the polyurea coating comprises a two-component system that includes a catalyst to effectuate curing of the polyurea on the bezel 100 at room temperature and without the need for a subsequent heat treating operation. In a particular embodiment, the two-component polyurea has the product designation UL XT 66 and is available from Ultimate Linings, LTD, of Houston Tex. After curing, the polyurea coating provides a weatherproof seal or surface over the applied portions of the bezel.
Various processes may be used to apply the organic coating to the bezel 100, including by pumping the material to a spraying device. Proportioning valves achieve the desired ratio of the two-components, which are mixed into a blended flow prior to discharge from the spaying device onto the bezel. Prior to application, the viscosity of the polyurea may lowered by heating the material in order to improve pumping efficiency and spraying. In a particular embodiment, the components of a two-component polyurea system are heated to about 150° F. In a particular embodiment, the components are proportioned and heated using a Reactor™ proportioning and heating system from Graco Inc. of Minneapolis, Minn.
Two-component polyurea provides a highly durable and weatherproof coating over the bezel 100. In addition to durability, the polyurea can provide an aesthetic finish that does not require a subsequent painting or coating step or a post-application heat treatment step to cure the coating. For example, where the bezel 100 includes external seams between the frame members 105, the polyurea coating can be applied and cured to form a surface that effectively conceals the seams to provide a finish with a uniform surface appearance on the bezel 100. The amount of material applied may be varied to achieve the desired thickness of the coating. In a particular embodiment, a finished polyurea coating of about 0.060 inches is utilized. Accordingly, a two-component polyurea system can enhance manufacturability and efficiency relative to conventional multi-step finishing processes.
With reference to
The bezel 100 is constructed such that the thickness of the bezel, i.e., the normal distance between the inner edge 107 and the peripheral surface 108, the portion visible when viewing the display enclosure 10 from the front, is minimized. That is, the bezel 100 has a low profile surrounding the display opening 111. For example, in a particular embodiment, the distance between inner edge 107 and the outer surface of the display enclosure 10 is less than about 25 mm. In other words, the area of the display opening 111 is maximized relative to the area of the display enclosure 10 defined by the peripheral surface 108. For example, in a particular embodiment, the area of the display opening 111 is at least about 92 percent of the area of the display enclosure 10. The low peripheral profile of the bezel 100 may enhance the overall look of the display enclosure 10, as well as minimizing the space needed in a mounting location for installation of an enclosed display. In multiple screen arrangements, where several displays are positioned horizontally and/or vertically next one another, the low profile of the bezel 100 may provide an enhanced seamless appearance of the displayed image(s) on the multiple display devices 20.
The display opening 111 is covered by the front cover 200. As shown in
As shown in
In various embodiments, the display enclosure 10 is constructed by assembling the plurality of frame members 105 to form the bezel 100. After the bezel 100 is formed, the display device 20 is introduced into the region defined by the bezel 100 through the lower opening 123. With the display device 20 in place within the region defined by the bezel, the lower plate 118 is secured to the bezel 100. By introducing the display device 20 through the lower opening 123 several advantages may be achieved, including a low profile for the bezel 100 and a well sealed enclosure. Because the display device 20 is introduced through the lower opening 123, the dimensions of various portions of the bezel 100 may be increased. For example, the rear surface 122 may be extended towards the interior of the bezel 100 to enhance the structural integrity of the display enclosure 10 with no increase in the profile of the bezel 100 because the display device 20 need not fit through the rear opening defined by the rear surface 122. Additionally, extending the rear surface 122 permits the front portions of the bezel 100, including the front surface 101 and the front cover ledge 109, to have a low profile.
The display enclosure 10 may include internal supports disposed within the display enclosure 10. As depicted in
Various other thermal control devices may be disposed within or at least partially within the display enclosure 10, to assist in maintaining the internal temperature of the display enclosure 10. Thermal control may be accomplished by including devices intended to add and/or remove heat from the display enclosure 10 depending on ambient conditions and/or the operating conduction of the display device 20. The various thermal control devices may work independently or in concert to assist in modulating the temperature inside the display enclosure 10 within the operating temperature range and/or storage temperature range of the display device 20 under various ambient conditions. In a particular embodiment, the display enclosure 10 is capable of maintaining the internal temperature inside the enclosure within the operating range of the display device 20 for an ambient temperature range of between about −20° C. and about 60° C. The thermal control devices within the display enclosure 10 may comprise passive and/or active devices.
Referring to
The first portion 610 of the thermoelectric module 600 faces an interior of the display enclosure 10. When an electric current is applied to the module 600 in a first direction, the first portion 610 is cooled and the second portion 620 is heated. When the electric current is applied to the module 600 in a second direction, opposite the first direction, the first portion 610 is heated and the second portion 620 is cooled.
In the example implementation shown, an internal fan 410 is horizontally positioned above the first portion 610 to draw air towards or away from the first portion 610 to increase the convective heating or cooling of the interior of the display enclosure 10. In some implementations, an internal fan 410 may be vertically positioned adjacent to the first portion 610 (e.g., perpendicular to an interior surface of the first portion 610) in the interior of the display enclosure 10 to draw air over the first portion 610 to increase the convective heating or cooling of the interior of the display enclosure 10. In some implementations, a second heat sink may be conductively coupled to the first portion 610 to increase the convective surface on the interior of the display enclosure 10 as well. The internal fan 410 may be positioned adjacent to and/or above the second heat sink to increase the airflow through the heat sink fins. The thermoelectric module 600 and/or the internal fan 410 are electrically coupled to a power source to provide operating power to the thermoelectric module 600 and/or the internal fan 410.
In some implementations, the thermally conductive grease or adhesive 650 may be omitted and the thermoelectric module 600 may simply abut and otherwise be conductively coupled to the rear cover assembly 300. In still other implementations, the thermoelectric module 600 may be coupled to other portions of the display enclosure 10, such as a side or other portion of the bezel 100. The side or other portion of the bezel 100 may include a heat sink for convectively dissipating the cooling or heating of the second portion 620 of the thermoelectric module 600. Still further, a plurality or an array of thermoelectric modules 600 may be used.
In another implementation, shown in
In some implementations, the internal fan 410 may be positioned above (as shown) and/or adjacent to the embedded thermoelectric module 600 to increase air flow over the first portion 610 to increase the convective heating or cooling of the interior of the display enclosure 10. In some implementations, a second heat sink may be thermally coupled to the first portion 610 to increase the convective surface on the interior of the display enclosure 10 as well. The internal fan 410 may be positioned adjacent to and/or above the second heat sink to increase the airflow through the heat sink fins. The thermoelectric module 600 and/or the internal fan 410 are electrically coupled to a power source to provide operating power to the thermoelectric module 600 and/or the internal fan 410.
In some implementations, the thermoelectric module 600 may be embedded within the rear cover assembly 300 such that an outer surface of the first portion 610 is flush with the interior surface of the rear cover assembly 300. In still other implementations, the thermoelectric module 600 may be embedded or integrated into other portions of the display enclosure 10, such as a side or other portion of the bezel 100. The side or other portion of the bezel 100 may include a heat sink for convectively dissipating the cooling or heating of the second portion 620 of the thermoelectric module 600. Still further, a plurality or an array of thermoelectric modules 600 may be used.
In still another implementation, shown in
The internal fan 410 may be positioned above (as shown) and/or adjacent to the thermoelectric module 600 to increase air flow over the first portion 610 to increase the convective heating or cooling of the interior of the display enclosure 10. In some implementations, a second heat sink may be thermally coupled to the first portion 610 to increase the convective surface on the interior of the display enclosure 10 as well. The internal fan 410 may be positioned adjacent to and/or above the second heat sink to increase the airflow through the heat sink fins. The thermoelectric module 600 and/or the internal fan 410 are electrically coupled to a power source to provide operating power to the thermoelectric module 600 and/or the internal fan 410.
The thermoelectric module 600 may be positioned within the rear cover assembly 300 such that an outer surface of the first portion 610 is flush with the interior surface of the rear cover assembly 300. In still other implementations, the thermoelectric module 600 positioned with the second portion 620 exposed in other portions of the display enclosure 10, such as a side or other portion of the bezel 100. Still further, a plurality or an array of thermoelectric modules 600 may be used.
In addition to, or in lieu of, the fans discussed above in reference to the thermoelectric modules 600, the display enclosure 10 may also include additional internal fans 410 located within the display enclosure 10, such as that shown in
Still referring to
The display enclosure 10 may also be provided with an ambient light sensor 540. The ambient light sensor 540 senses the light level outside the display enclosure 10 and may be mounted to the bezel 100 or beneath the front cover 200. The ambient light sensor 540 is electrically coupled to the power supply 500 and the display controller 520. The display controller 520 receives input from the ambient light sensor 540 and, based on the input signal, may be configured to adjust the displayed image, for example, the brightness and/or the contrast, generated by the display device 20. For instance, under relatively low ambient light conditions, such as at night when the display enclosure 10 is located outdoors, the display controller 520 may be configured to automatically decrease the brightness of the display device 20 based on the input from the ambient light sensor 540. In other instances, such as under relatively bright ambient light conditions, such as during the day when the display enclosure 10 is located outdoors, the display controller 520 may be configured to automatically increase the brightness of the display device 20 based on the input from the ambient light sensor 540.
The display enclosure 10 may also be equipped with features that enable communication between the display device 20 and a remote control device configured to control and the display device 20. The display enclosure 10 may include a remote control input 550. The remote control input 550 comprises an infrared sensor in a particular embodiment. The remote control input 550 is electrically coupled to the display controller 520 and may be mounted to the bezel 100 or located beneath the front cover 200 to receive input from a separate remote control device configured to control the operation of the display device.
In addition to the display controller 520, the display enclosure 10 includes a thermal controller 510. As shown in
The temperature sensor 560 is electrically coupled to the thermal controller 510 and the power supply 500 and is configured to output a signal indicative of a temperature detected by the temperature sensor 560. The temperature sensor 560 may include a thermistor, a thermocouple, a resistance temperature detector, or any other temperature sensor. The signal output from the temperature sensor 560 may be a voltage value that corresponds to a detected temperature. The thermal controller 510 may receive and use the voltage value representative of the temperature as an input for controlling the one or more fans 410 and/or the thermoelectric module 600, as will be described in greater detail below.
The temperature sensor 560 is positioned within the display enclosure 10 to measure the internal temperature of the display enclosure 10. In some implementations, the temperature sensor 560 may be positioned near the thermoelectric module 600. For example, the temperature sensor 560 may be positioned adjacent to a thermoelectric module 600. In other instances, the temperature sensor 560 may be positioned remote from the thermoelectric module 600, such as at an opposite corner of the display enclosure 10 relative to the thermoelectric module 600. In still further implementations, the temperature sensor 560 may be arbitrarily positioned within the display enclosure 10.
The humidity sensor 570 is also electrically coupled to the thermal controller 510 and the power supply 500 and is configured to outputs a signal indicative of a humidity detected by the humidity sensor 570. The humidity sensor 570 may include a hygrometer, a humistor, or any other humidity sensor. The signal output from the humidity sensor 570 may be a voltage value that corresponds to a detected humidity, such as a relative humidity. The thermal controller 510 may receive and use the voltage value representative of the humidity as an input for controlling the one or more fans 410 and/or the thermoelectric module 600, as will be described in greater detail below.
The humidity sensor 570 is positioned within the display enclosure 10 to measure the internal humidity of the display enclosure 10. In some implementations, the humidity sensor 570 may be positioned near the temperature sensor 560 and/or the thermoelectric module 600. For example, the humidity sensor 570 may be positioned adjacent to the temperature sensor 560 such that the humidity and temperature measurements are taken at substantially the same spatial position. In other instances, the humidity sensor 570 may be positioned remote from the temperature sensor 560. In still further implementations, the humidity sensor 570 may be arbitrarily positioned within the display enclosure 10. In some implementations, the humidity sensor 570 may be omitted.
The thermal controller 510 is further electrically coupled to the H-Bridge 580. The H-Bridge 580 is also electrically coupled to one or more thermoelectric modules 600 and the power supply 500. The thermal controller 510 is configured to control the direction of current supplied from the power supply 500 to the one or more thermoelectric modules 600 via the H-Bridge 580. In one implementation, the thermal controller 510 may control the current flow to the one or more thermoelectric modules 600 by using one half of the H-Bridge 580. That is, the thermal controller 510 may, using the H-Bridge 580, control whether current flows in a first direction or a second direction through the thermoelectric modules 600. As noted above, when an electric current is applied to the one or more thermoelectric modules 600 in the first direction, the first portion 610 of each thermoelectric module 600 is cooled and the second portion 620 of each thermoelectric module 600 is heated. When the electric current is applied to the one or more thermoelectric modules 600 in the second direction, opposite the first direction, the first portion 610 of each thermoelectric module 600 is heated and the second portion 620 of each thermoelectric module 600 is cooled. The second portion 620 may be conductively coupled to or otherwise associated with the rear cover assembly 300 for heat transfer to the external atmosphere of the display enclosure 10. Accordingly, it may be appreciated that the internal temperature of the display enclosure 10 and/or portions thereof may be actively regulated by the thermal controller 510 using the H-Bridge 580.
The thermal controller 510 may control the current flowing through the one or more thermoelectric modules 600 using pulse width modulation (PWM). The thermal controller 510 may control the duty cycle of the pulse width modulation to vary the heating or cooling provided by the one or more thermoelectric modules 600. When the duty cycle of the pulse width modulation reaches 100%, then the maximum current is applied and the maximum heating or cooling is provided by the one or more thermoelectric modules 600.
One or more fans 410 may be electrically coupled the thermal controller 510 and the power supply 500. The thermal controller 510 may be configured to control the one or more fans 410. As discussed above, the one or more fans 410 may be positioned to circulate air within the display enclosure 10. In some implementations, the one or more fans 410 may be positioned relative to the one or more thermoelectric modules 600 to increase the convective heat transfer from the first portion 610 (e.g., adjacent to, above, etc.) to the interior air of the display enclosure 10 to assist the heating or cooling provided by the first portion 610 of the one or more thermoelectric modules 600.
Referring to
If it is determined that the detected temperature T is above the first temperature set point, Tcool (block 720) then the thermal controller 510 may be configured to activate one or more of the fans 410 and switch the H-bridge 580 to energize and drive current thru the one or more thermoelectric modules 600 in the direction which will cause the first surface 610 of each of the one or more thermoelectric modules 600 to be cooled (block 730). Accordingly, the interior of the display enclosure 10 may be cooled by the one or more thermoelectric modules 600 and the one or more fans 410 circulating air. The second portion 620 of the one or more thermoelectric modules 600 may be coupled to the heat sink portion of the rear cover assembly 300. When the second portion 620 is heated as the first portion 610 is cooled, the second portion 620 thermally conducts heat through the heat sink portion of the rear cover assembly 300 to dissipate the heat to the atmosphere. The process 700 may then return to block 710 to receive the temperature T from the temperature sensor 560. In some implementations, the thermal controller 510 is configured to operate the one or more fans 410 and the one or more thermoelectric modules 600 until the detected temperature T falls below the first temperature set point Tcool as shown in
If it is determined that the detected temperature T does not exceed the first temperature set point Tcool (block 720), then a determination may be made by the thermal controller 510 whether the detected temperature T is below a second temperature set point Theat (block 740). The second temperature set point may be set as a temperature below the operational range of the display device 20 or that would degrade the operation of the display device 20. In some implementations, the second temperature set point may be between −20° C., inclusive, and 10° C., inclusive. In one example, the second temperature set point may be set at approximately 5° C.
If it is determined that the detected temperature T is below the second temperature set point Theat (block 740) then the thermal controller 510 may be configured to activate one or more of the fans 410 and switch the H-bridge 580 to energize and drive current thru the one or more thermoelectric modules 600 in the direction which will cause the first surface 610 of each of the one or more thermoelectric modules 600 to be heated (block 750). Accordingly, the interior of the display enclosure 10 may be heated by the one or more thermoelectric modules 600 and the one or more fans 410 circulating air. The second portion 620 of the one or more thermoelectric modules 600 may be coupled to the heat sink portion of the rear cover assembly 300. When the second portion 620 is cooled as the first portion 610 is heated, the second portion 620 thermally cools the heat sink portion of the rear cover assembly 300 through conduction to dissipate the cool to the atmosphere. The process 700 may then return to block 710 to receive the temperature T from the temperature sensor 560. In some implementations, the thermal controller 510 is configured to operate the one or more fans 410 and the one or more thermoelectric modules 600 until the detected temperature T increases above the second temperature set point Theat as shown in
If it is determined that the detected temperature T is not below the second temperature set point Theat, (block 740), then a determination may be made by the thermal controller 510 whether the one or more fans 410 and the one or more thermoelectric modules 600 are active (block 760). If the one or more fans 410 and the one or more thermoelectric modules 600 are not active, then the process 700 may return to block 710 to receive the temperature T from the temperature sensor 560. If the one or more fans 410 and the one or more thermoelectric modules 600 are active, then the process 700 may proceed to deactivate the one or more fans 410 and the one or more thermoelectric modules 600 (block 770). The process 700 may then return to block 710 to receive the temperature T from the temperature sensor 560.
In some implementations, the one or more fans 410 and the one or more thermoelectric modules 600 may be operated by the thermal controller 510 while the display device 20 is off or in a sleep mode to mitigate potential damage to the display device 20 that could be caused by ambient temperatures below a storage temperature of the device, such as, for example, below −20° C. or above 45° C. In some other implementations, the process 700 may be performed periodically, such as every minute, five minutes, ten minutes, thirty minutes, one hour, etc.
In another example configuration, shown as process 800 in
The received temperature T may be compared against a first temperature set point, such as Tcool, to determine whether the temperature detected T by the temperature sensor 560 is above a first temperature set point (block 820). In some implementations, the first temperature set point may be between 30° C., inclusive, and 45° C., inclusive. In one example, the first temperature set point Tcool may be set at approximately 30° C.
If it is determined that the detected temperature T is above the first temperature set point Tcool, (block 820), then a determination may be made by the thermal controller 510 whether the received humidity H is less than or equal to a maximum humidity Hmax (block 830). For example, the maximum humidity Hmax may be a value indicative of a relative humidity between 75% and 100%. In one example, the maximum humidity Hmax may be set as a value indicative of a relative humidity of approximately 85%. If the value of the received humidity H within the display enclosure 10 is below the maximum humidity Hmax, then the thermal controller 510 may be configured to activate one or more of the fans 410 and switch the H-bridge 580 to energize and drive current thru the one or more thermoelectric modules 600 in the direction which will cause the first surface 610 of each of the one or more thermoelectric modules 600 to be cooled (block 840). Accordingly, the interior of the display enclosure 10 may be cooled by the one or more thermoelectric modules 600 and the one or more fans 410 circulating air. The second portion 620 of the one or more thermoelectric modules 600 may be coupled to the heat sink portion of the rear cover assembly 300. When the second portion 620 is heated as the first portion 610 is cooled, the second portion 620 thermally conducts heat through the heat sink portion of the rear cover assembly 300 to dissipate the heat to the atmosphere. The process 800 may then return to block 810 to receive the temperature T from the temperature sensor 560 and the humidity H from the humidity sensor 570. In some implementations, the thermal controller 510 is configured to operate the one or more fans 410 and the one or more thermoelectric modules 600 until the detected temperature T falls below the first temperature set point Tcool, as shown in
If the value of the received humidity H within the display enclosure 10 increases above the maximum humidity Hmax, then condensation may occur within the display enclosure 10. Such condensation may potentially harm the components of the display enclosure 10 and/or the display device 20. Accordingly, if the value of the received humidity H increases above the maximum humidity Hmax, (block 830), then the thermal controller 510 may be configured to deactivate the one or more thermoelectric modules 600 (block 850). In the present example, the one or more fans 410 may remain active to circulate the air within display enclosure 10 to assist in the transfer of thermal energy from the air within the display enclosure 10 to the heat sink portion of the rear cover assembly 300, even if the one or more thermoelectric module 600 is no longer active. In another implementation, both of the one or more fans 410 and the one or more thermoelectric modules 600 may be deactivated when the received humidity H is above a maximum humidity Hmax (block 830). In some implementations, a dew point temperature may be determined by the thermal controller 510 based on the received temperature T and the received humidity H. The received temperature T may be compared to the calculated dew point temperature in lieu of, or in addition to, the comparison of the received humidity H, is above a maximum humidity Hmax by the thermal controller 510 (block 830). The process 800 may then return to block 810 to receive the temperature T from the temperature sensor 560 and the humidity H from the humidity sensor 570.
If it is determined that the detected temperature T does not exceed the first temperature set point Tcool, (block 820), then a determination may be made by the thermal controller 510 whether the detected temperature T is below a second temperature set point Theat (block 860). The second temperature set point may be set as a temperature below the operational range of the display device 20 or that would degrade the operation of the display device 20. In some implementations, the second temperature set point may be between −20° C., inclusive, and 10° C., inclusive. In one example, the second temperature set point may be set at approximately 5° C.
If it is determined that the detected temperature T is below the second temperature set point Theat, (block 860) then the thermal controller 510 may be configured to activate one or more of the fans 410 and switch the H-bridge 580 to energize and drive current thru the one or more thermoelectric modules 600 in the direction which will cause the first surface 610 of each of the one or more thermoelectric modules 600 to be heated (block 870). Accordingly, the interior of the display enclosure 10 may be heated by the one or more thermoelectric modules 600 and the one or more fans 410 circulating air. The second portion 620 of the one or more thermoelectric modules 600 may be coupled to the heat sink portion of the rear cover assembly 300. When the second portion 620 is cooled as the first portion 610 is heated, the second portion 620 thermally cools the heat sink portion of the rear cover assembly 300 through conduction to dissipate the cool to the atmosphere. The process 800 may then return to block 810 to receive the temperature T from the temperature sensor 560 and the humidity H from the humidity sensor 570. In some implementations, the thermal controller 510 is configured to operate the one or more fans 410 and the one or more thermoelectric modules 600 until the detected temperature T increases above the second temperature set point Theat, as shown in
If it is determined that the detected temperature T is not below the second temperature set point Theat, (block 860), then a determination may be made by the thermal controller 510 whether the one or more fans 410 and the one or more thermoelectric modules 600 are active (block 880). If the one or more fans 410 and the one or more thermoelectric modules 600 are not active, then the process 800 may then return to block 810 to receive the temperature T from the temperature sensor 560 and the humidity H from the humidity sensor 570. If the one or more fans 410 and the one or more thermoelectric modules 600 are active, then the process 800 may proceed to deactivate the one or more fans 410 and the one or more thermoelectric modules 600 (block 890). The process 800 may then return to block 810 to receive the temperatureT from the temperature sensor 560 and the humidity H from the humidity sensor 570.
In some implementations, the one or more fans 410 and the one or more thermoelectric modules 600 may be operated by the thermal controller 510 while the display device 20 is off or in a sleep mode to mitigate potential damage to the display device 20 that could be caused by ambient temperatures below a storage temperature of the device, such as, for example, below −20° C. or above 45° C. In some other implementations, the process 800 may be performed periodically, such as every minute, five minutes, ten minutes, thirty minutes, one hour, etc.
In some implementations, a pair of cooling temperature set points Tcool_1 and Tcool_2 may be used by the thermal controller 510 when activating the one or more thermoelectric modules 600. For example, in one configuration, when the received temperature T is above the first cooling temperature set point Tcool_1, then the thermal controller 510 may activate the one or more fans 410 while the one or more thermoelectric modules 600 remain deactivated. If the received temperature T is above the second cooling temperature set point Tcool_2, then the thermal controller 510 may also activate the one or more thermoelectric modules 600 such that the first portion 610 of each is cooled. In some implementations, the thermal controller 510 is configured to operate the one or more fans 410 and the one or more thermoelectric modules 600 until the detected temperature T falls below the second cooling temperature set point Tcool_2. When the detected temperature T falls below the second cooling temperature set point Tcool_2, then the one or more thermoelectric modules 600 may be deactivated by the thermal controller 510 while the one or more fans 410 remain activated. When the detected temperature T falls below the first cooling temperature set point Tcool_1, then the one or more fans 410 may be deactivated as well. In other implementations, both the one or more fans 410 and the one or more thermoelectric modules 600 may remain active until the detected temperature T falls below the first cooling temperature set point Tcool_1. In other implementations, the thermal controller 510 may be configured to operate the one or more fans 410 and/or the one or more thermoelectric modules 600 for a predetermined period of time after the received temperature T is above the first and/or the second cooling temperature set points Tcool_1 and Tcool_2. The first and second cooling temperature set points Tcool_1 and Tcool_2 may be between 30° C., inclusive, and 45° C., inclusive. In one example, the first cooling temperature set point Tcool_1, may be set at approximately 30° C. and the second cooling temperature set point Tcool_2 may be set at approximately 35° C. Such a pair of cooling temperature set points may be used as part of process 700 at blocks 720 and 730 of
In yet another implementation, the pair of cooling temperature set points Tcool_1 and Tcool_2 may be used to incrementally increase the cooling provided by the first portion 610 of each of the one or more thermoelectric modules 600. For example, in one configuration, when the received temperature T is above the first cooling temperature set point Tcool_1, then the thermal controller 510 may activate the one or more fans 410 and the one or more thermoelectric modules 600 to cool the interior of the display enclosure 10. The thermal controller 510 may be configured to control the current flowing through the one or more thermoelectric modules 600 using pulse width modulation (PWM). The duty cycle for the pulse width modulation may be determined based on the received temperature T relative to the first and second cooling temperature set points Tcool_1 and Tcool_2. For example, the first and second cooling temperature set points Tcool_1 and Tcool_2 may be between 30° C., inclusive, and 45° C., inclusive. In one example, the first cooling temperature set point Tcool_1 may be set at approximately 30° C. and the second cooling temperature set point Tcool_2 may be set at approximately 35° C. In one example, the duty cycle for the pulse width modulation may be determined by
Thus, the thermal controller 510 may increase the duty cycle of the pulse width modulation provided to control the thermoelectric module 600, and therefore the cooling effect provided, based on the temperature T detected by the temperature sensor 560 relative to the cooling temperature set points. Of course it should be understood that the cooling temperature set points are merely examples and other cooling temperature set points may be used. Such a pair of cooling temperature set points and control of the thermoelectric modules 600 via pulse width modulation duty cycle may be used as part of process 700 at blocks 720 and 730 of
Similarly, in some implementations, a pair of heating temperature set points Theat_1 and Theat_2 may be used by the thermal controller 510. For example, in one configuration, when the received temperature T falls below the first heating temperature set point Theat_1 then the thermal controller 510 may activate the one or more thermoelectric modules 600 such that the first portion 610 of each is heated while the one or more fans 410 remain deactivated. If the received temperature T falls below the second heating temperature set point Theat_2 then the thermal controller 510 may also activate the one or more fans 410 to further circulate the heated air from the first portions 610 of each of the one or more thermoelectric modules 600. In some implementations, the thermal controller 510 is configured to operate the one or more fans 410 and the one or more thermoelectric modules 600 until the detected temperature T increases above the second heating temperature set point Theat_2 When the detected temperature T increases above the second heating temperature set point Theat_2 then the one or more thermoelectric modules 600 may be deactivated by the thermal controller 510 while the one or more fans 410 remain activated to circulate the air within the display enclosure 10. When the detected temperature T increases above the first heating temperature set point Theat_1 then the one or more fans 410 may be deactivated as well. In other implementations, both the one or more fans 410 and the one or more thermoelectric modules 600 may remain active until the detected temperature T increases above the first heating temperature set point Theat_1. In other implementations, the thermal controller 510 may be configured to operate the one or more fans 410 and/or the one or more thermoelectric modules 600 for a predetermined period of time after the received temperature T increases above the first and/or the second heating temperature set points Theat_1 and Theat_2. The first and second heating temperature set points Theat_1 and Theat_2 may be between −20° C., inclusive, and 10° C., inclusive. In one example, the first heating temperature set point Theat_1 may be set at approximately 10° C. and the second heating temperature set point Theat_2 may be set at approximately 5° C. Such a pair of heating temperature set points may be used as part of process 700 at blocks 740 and 750 of
In yet another implementation, the pair of heating temperature set points Theat_1 and Theat_2, may be used to incrementally increase the heating provided by the first portion 610 of each of the one or more thermoelectric modules 600. For example, in one configuration, when the received temperature T is below the first heating temperature set point Theat_1 then the thermal controller 510 may activate the one or more fans 410 and the one or more thermoelectric modules 600 to heat the interior of the display enclosure 10. The thermal controller 510 may be configured to control the current flowing through the one or more thermoelectric modules 600 using pulse width modulation (PWM). The duty cycle for the pulse width modulation may be determined based on the received temperature T relative to the first and second heating temperature set points Theat_1 and Theat_2. For example, the first and second heating temperature set points Theat_1 and Theat_2 may be between −20° C., inclusive, and 10° C., inclusive. In one example, the first heating temperature set point Theat_1 may be set at approximately 10° C. and the second heating temperature set point Theat_2 may be set at approximately 5° C. In one example, the duty cycle for the pulse width modulation may be determined by
Thus, the thermal controller 510 may increase the duty cycle of the pulse width modulation provided to control the thermoelectric module 600, and therefore the heating effect provided, based on the temperature T detected by the temperature sensor 560 relative to the heating temperature set points. Of course it should be understood that the heating temperature set points are merely examples and other heating temperature set points may be used. Such a pair of heating temperature set points and control of the thermoelectric modules 600 via pulse width modulation duty cycle may be used as part of process 700 at blocks 740 and 750 of
The foregoing description of embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the present invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the present invention. The embodiments were chosen and described to explain the principles of the present invention and its practical application to enable one skilled in the art to utilize the present invention in various embodiments and with various modifications as are suited to the particular use contemplated.
The present application claims the benefit of and priority to U.S. Provisional Patent Application Ser. No. 61/834,303, filed Jun. 12, 2013, which is incorporated herein by reference in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/US14/42095 | 6/12/2014 | WO | 00 |
Number | Date | Country | |
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61834303 | Jun 2013 | US |