US20160286691A1 - Outdoor electronic equipment enclosures and related methods - Google Patents

Abstract

An electronic equipment enclosure for outdoor deployment includes a housing defining an interior and having an intake port, an exhaust port, an airflow path extending from the intake port to the exhaust port, and an equipment bay for receiving the electronic equipment. The equipment bay is positioned in the airflow path. The equipment enclosure further includes an intake fan for creating positive pressure within the interior of the housing and a pressure-activated damper having an open position for allowing air to exit the enclosure through the exhaust port in response to positive pressure within the interior of the housing and a closed position for preventing external air and/or water from entering the enclosure through the exhaust port when the intake fan is not operating. Other example equipment enclosures and methods are also disclosed.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• This application is a divisional of U.S. patent application Ser. No. 12/956,829 filed Nov. 30, 2010, which claims the benefit of U.S. Provisional Application No. 61/265,193 filed Nov. 30, 2009. The entire disclosures of the above applications are incorporated herein by reference.
FIELD
• The present disclosure relates to outdoor electronic equipment enclosures and related methods.
BACKGROUND
• This section provides background information related to the present disclosure which is not necessarily prior art.
• Electronic equipment enclosures are often deployed out-of-doors for housing and protecting various types of electronic equipment such as telecommunications equipment, cable television (CATV) equipment and/or data transmission equipment. Such equipment is sometimes referred to as “outside plant equipment.” The equipment enclosures may be located virtually anywhere on Earth, where they may be exposed to inhospitable climates having very warm, cold, wet, dry, dusty, sandy, salty and/or windy conditions.
SUMMARY
• According to one aspect of the present disclosure, an outdoor electronic equipment enclosure includes a housing defining an interior and having an intake port, an exhaust port, an airflow path extending from the intake port to the exhaust port, and an equipment bay for receiving the electronic equipment. The equipment bay is positioned in the airflow path between the intake port and the exhaust port. The enclosure further includes an intake fan for creating positive pressure within the interior of the housing when the fan is operating, and a pressure-activated damper having an open position for allowing air to exit the enclosure through the exhaust port in response to positive pressure within the interior of the housing and a closed position for preventing external air and/or water from entering the enclosure through the exhaust port when the intake fan is not operating.
• According to another aspect of the present disclosure, an outdoor electronic equipment enclosure includes a housing defining an interior and having an intake port, an exhaust port and an airflow path extending from the intake port to the exhaust port. The enclosure further includes at least one fan for moving air through the airflow path extending from the intake port to the exhaust port, a first sensor for measuring an air temperature external to the enclosure, a second sensor for measuring an air temperature within the interior of the housing, and a controller operatively coupled to the fan, the first sensor and the second sensor. The controller is configured to selectively operate the fan to maintain a defined temperature differential between the air temperature external to the enclosure and the air temperature within the interior of the housing to thereby inhibit condensation within the interior of the housing.
• According to yet another aspect of the present disclosure, a method is provided for inhibiting condensation in an outdoor electronic equipment enclosure. The method includes determining a maximum expected dew point at a location of the outdoor electronic equipment enclosure, and maintaining an air temperature within an interior of the enclosure above the determined maximum expected dew point to thereby avoid condensation within the interior of the enclosure.
• Further aspects and areas of applicability will become apparent from the description provided herein. It should be understood that various aspects of this disclosure may be implemented individually or in combination with one or more other aspects. It should also be understood that the description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
• The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
• FIG. 1 is a block diagram of an outdoor electronic equipment enclosure according to one example embodiment of the present disclosure.
• FIG. 2 is a block diagram of an outdoor electronic equipment enclosure according to another example embodiment of this disclosure.
• FIG. 3 is an enlarged view of one flap of the pressure-activated damper shown inFIG. 2.
• FIG. 4 is a block diagram of an outdoor electronic equipment enclosure having a door according to yet another example embodiment of the present disclosure.
DETAILED DESCRIPTION
• Example embodiments will now be described more fully with reference to the accompanying drawings.
• Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
• The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
• When an element or layer is referred to as being “on”, “engaged to”, “connected to” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to”, “directly connected to” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
• An electronic equipment enclosure for outdoor applications according to one example embodiment of the present disclosure is illustrated inFIG. 1 and indicated generally by reference number50. As shown inFIG. 1, the enclosure50 includes a housing52 defining aninterior54. The housing52 includes anintake port56 and anexhaust port58. An airflow path extends between theintake port56 and theexhaust port58. The enclosure further includes at least onefan60 for moving air through the airflow path extending from theintake port56 to theexhaust port58, asensor62 for measuring an air temperature external to the enclosure50, asensor64 for measuring an air temperature within the interior of the housing52, and at least onecontroller68 operatively coupled to thefan60 and thesensors62,64. Thecontroller68 may be configured to selectively operate thefan60 to maintain a defined temperature differential between the air temperature external to the enclosure50 and the air temperature within theinterior54 of the housing52. In this manner, thecontroller68 may inhibit the formation of condensation within the interior of the housing.
• The defined temperature differential maintained by thecontroller68 may be a fixed temperature differential. For example, thecontroller68 may be configured to maintain the internal temperature within theinterior54 of the housing52 approximately three or five degrees Celsius above the external (i.e., ambient) temperature. Alternatively, the defined temperature differential may vary depending on one or more other parameters. For example, thecontroller68 may be configured to maintain the internal temperature at a first temperature when the external temperature falls within a first range (e.g., above zero degrees Celsius), and at a second temperature when the external temperature falls within a second range (e.g., below zero degrees Celsius).
• The housing52 may include a door, a removable panel or another suitable provision for providing access to components within theinterior54 of the housing52. Accordingly, theintake port56 and/or thefan60 may be positioned over an opening in a door, a removable panel or another suitable portion of the housing52, with the airflow path extending through such opening, as will be further apparent from the description below.
• As shown inFIG. 1, the enclosure50 may optionally include aheater70. In that event, thecontroller68 may be configured to control operation of theheater70 as necessary to maintain the defined temperature differential discussed above.
• Under typical operating conditions, thecontroller68 can reduce the temperature within the enclosure50 by turning on or increasing the speed of one or more intake fans. Conversely, the controller can typically increase the temperature within the enclosure by turning off or decreasing the speed of one or more intake fans and/or by turning on one or more heaters. Although the enclosure50 ofFIG. 1 does not include an air conditioning unit for providing cooling and/or controlling humidity, thecontroller68 may still inhibit formation of condensation or otherwise control humidity by maintaining the defined temperature differential. In other embodiments, one or more air conditioners can be employed for cooling and/or controlling humidity within theinterior54 of the housing52.
• When deployed in an outdoor environment, the enclosure50 will house and protect one or more pieces ofoutside plant equipment72, as indicated generally inFIG. 1.
• Although not shown inFIG. 1, the enclosure50 may also include hydrophobic or other filter(s) and/or damper(s) for preventing water and/or contaminates from reaching theinterior54 of the housing52 through theintake port56 or theexhaust port58.
• As an alternative to maintaining the defined temperature differential, thecontroller68 may be configured to maintain a particular temperature or humidity level in the enclosure50, as further explained below. In this regard, the enclosure50 may include components, such as one or more humidity sensors, in addition to the components illustrated inFIG. 1.
• FIG. 2 illustrates an outdoorelectronic equipment enclosure100 according to another example embodiment of the present disclosure. As shown inFIG. 2, theenclosure100 includes ahousing102 defining an interior104 and having an intake port106, anexhaust port108, an airflow path extending from the intake port106 to theexhaust port108, and anequipment bay110 for receiving the electronic equipment. Theequipment bay110—which may be at any desired location(s) within theinterior104 of theenclosure100—is positioned in the airflow path between the intake port106 and theexhaust port108. In this manner, air passes around and/or through the electronic equipment horizontally, vertically and/or at other angles as may be necessary or desired for controlling the temperature of the electronic equipment.
• Theenclosure100 further includes at least oneintake fan114 and at least one pressure-activateddamper116. Theintake fan114 creates positive pressure within theinterior104 of thehousing102 when thefan114 is operating. The pressure-activateddamper116 is movable between an open position for allowing air to exit theenclosure100 through theexhaust port108 in response to positive pressure within theinterior104 of thehousing102, and a closed position for preventing external air and/or water from entering theenclosure100 through theexhaust port108 when theintake fan114 is not operating.
• The pressure-activateddamper116 may be a passive damper, such as a gravity-operated damper, or an active damper such as an electromechanical damper. In some embodiments, including the embodiment shown inFIG. 2, the pressure-activateddamper116 is a gravity-operated damper that automatically pivots open in response to positive pressure within the interior of the enclosure. Thedamper116 may include several flaps formed of plastic, rubber, metal or any other suitable material or combination of materials.FIG. 3 illustrates one of the damper flaps in the open position.FIG. 3 also illustrates that when thedamper116 is in the closed position, each flap is preferably oriented between about zero degrees (i.e., vertically) and about forty-five degrees from the vertical axis of the enclosure. It should be understood, however, that other dampers and flap orientations may be employed, including various types of active dampers, without departing from the scope of this disclosure.
• As shown inFIG. 2, theenclosure100 may also include afilter112 positioned in the airflow path between the intake port106 and theequipment bay110. In that event, positive pressure created within the interior of the enclosure by theintake fan114 forces filtered air out of theenclosure100 through theexhaust port108 and any cracks or leaks in theenclosure100. Theenclosure100 ofFIG. 2 does not include an exhaust fan associated with the exhaust port, which could create negative pressure within the enclosure that, in turn, could draw unfiltered outdoor air into theenclosure100 through any cracks or leaks in the enclosure. However, exhaust fans may be employed in other embodiments without departing from the scope of this disclosure. When exhaust fan(s) are employed, they are preferably sized and/or operated so that the intake fan(s) and the exhaust fan(s) collectively maintain positive pressure (or zero pressure) within the interior of the enclosure.
• The filter112 (and the filters employed in the embodiment ofFIG. 1, if any) may be a hydrophobic and/or membrane filter for preventing solid and/or liquid contaminates from reaching theinterior104 of thehousing102 via the intake port106. For example, thehydrophobic filter112 may be a hydrophobic membrane filter. Examples of suitable hydrophobic membrane filters include those available from Gore and Schrofftec. In some embodiments, the hydrophobic filter has a pore size sufficient to filter out, among other things, salt particles in marine environments. Alternatively, other types of filters may be employed. If a filter capable of blocking liquids is not employed, the enclosure will preferably including a drain for removing any water that passes through the filter before the water can reach the electronic equipment within the enclosure.
• Theintake fan114 is adapted to draw outside air through the intake port106 and thehydrophobic filter112, and create positive pressure within theinterior104 of theenclosure100. Theintake fan114 may have one or more discrete speeds, and may be a variable-speed fan. As outdoor air is drawn through the hydrophobic filter, the hydrophobic filter removes solids and/or liquids from the air before the air enters the interior of the enclosure. When thedamper116 is in the open position, air preferably exits (and does not enter) theenclosure100 through theexhaust port108 due to the positive pressure within the interior of thehousing102.
• When the intake fan is off, thehydrophobic filter112 prevents solid and/or liquid contaminants from entering the enclosure through the intake port106. Further, when the intake fan is off, the flaps of the pressure-activateddamper116 close (due to the force of gravity) to prevent solid and/or liquid contaminates from entering the enclosure through theexhaust port108. Accordingly, theenclosure100 is not required to have a hydrophobic filter associated with the exhaust port, in addition to thehydrophobic filter112 associated with the intake port106. Thus, the expense of an exhaust port hydrophobic filter can be avoided, if desired. Alternatively, the exhaust port may also be provided with a hydrophobic or other filter, if desired, to further ensure no solid and/or liquid contaminants enter the enclosure via theexhaust port108.
• As shown inFIG. 2, theenclosure100 may also include, if desired, aparticle filter118 positioned in the airflow path upstream of the hydrophobic filter112 (i.e., air entering the intake port106 passes through theparticle filter118 before reaching the hydrophobic filter112), and aheater120, which may be an electric heater. A controller (not shown), such as an environmental control unit (ECU), may also be provided for selectively controlling operation of the fan(s) and heater(s) as may be desired for any given application of these teachings.
• The controller may be configured to operate fan(s), heater(s) and air conditioners (if employed) as necessary to maintain the internal temperature or humidity of the enclosure at a defined level. For example, the controller may be configured to operate the heater(s) as necessary to maintain the air temperature within the enclosure above the freezing temperature of water (i.e., zero degrees Celsius) or some other desired temperature (above or below zero degrees Celsius). In some embodiments, the controller is configured to shutdown the intake fan(s) and turn on one or more circulating fans within the interior of the enclosure before operating the heater. The controller may also be configured to maintain a positive temperature differential between the internal temperature of the enclosure and the external (i.e., ambient) temperature outdoors, as described above, using one or more sensors (not shown inFIG. 2). Further still, the controller may be configured to maintain the internal temperature at or above a setpoint temperature, which may be greater than the maximum expected dew point at the location of the enclosure, as described below. At the same time, the controller may also maintain the internal temperature of the enclosure within operating limits of the electronic equipment within the enclosure. The controller may be a separate component, such as an environmental control unit, or may be integrated with the intake fan(s), heater(s), sensor(s), and/or other components.
• Additionally, or alternatively, the controller may be configured to inhibit condensation by controlling the relative humidity within the interior of the enclosure. For example, the controller may be configured to maintain the relative humidity in the enclosure below a particular setpoint, such as 65% relative humidity. Maintaining a low relative humidity may also reduce corrosion of equipment within the enclosure, which can occur even without condensation.
• As noted above, the controller can be configured to control humidity and/or inhibit formation of condensation without employing an air conditioner. It should be understood, however, that one or more air conditioners may be employed for cooling and/or controlling humidity within the interior of the housing without departing from the scope of this disclosure.
• When deployed in an outdoor environment, theenclosure100 will house and protect one or more pieces ofoutside plant equipment72, as indicated generally inFIG. 2.
• The housing100 (as well as the housing50 ofFIG. 1) may have a monolithic or multi-part construction, possibly including one or more doors, removable panels, or other provisions for accessing the interior of the housing. In some embodiments, including the example embodiment shown inFIG. 4, ahousing300 may include adoor302 having anopening306 extending therethrough. The airflow path extends through door opening306, and theintake fan308 is mounted to thedoor302 over theopening306 for drawing preferably filtered air into the interior of the enclosure.
• Baffles may also be provided on the intake and exhaust ports (as shown inFIGS. 1-3) to force entering and/or exiting air through a convoluted path, to reduce airspeed and protect the damper flaps (if applicable).
• When the enclosures described herein are deployed outdoors, they can house and protect various types of electronic equipment. By employing one or more teachings herein for controlling environmental conditions (e.g., temperature, humidity and/or condensation) within the enclosure, the need to use hardened electronic equipment can be reduced or eliminated, resulting in further cost savings. Similarly, due to the enclosure designs, electronic equipment rated for near-ambient temperatures and/or non-condensing humidity levels (e.g., non-hardened equipment) may be advantageously deployed in the enclosures.
• According to another aspect of the present disclosure, a method is provided for inhibiting condensation in an outdoor electronic equipment enclosure. The method includes determining a maximum expected dew point on an external side of the enclosure, and maintaining an air temperature within an interior of the enclosure above the determined maximum expected dew point to thereby inhibit formation of condensation within the interior of the enclosure.
• If the equipment enclosure includes a ventilating fan (such as an intake or exhaust fan) and/or a heater, the fan and/or heater may be selectively operated to maintain the air temperature within the enclosure interior above the determined maximum expected dew point.
• The method described above can be practiced with a wide variety of outdoor electronic equipment enclosures including, without limitation, the example outdoor equipment enclosures described above.
• The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention.

Claims (13)

1. An outdoor electronic equipment enclosure, comprising:

a housing defining an interior and having an intake port, an exhaust port, an airflow path extending from the intake port to the exhaust port, and an equipment bay for receiving electronic equipment, the equipment bay positioned in the airflow path between the intake port and the exhaust port;

an intake fan for creating positive pressure within the interior of the housing when the intake fan is operating; and

a pressure-activated damper having an open position for allowing air to exit the enclosure through the exhaust port in response to positive pressure within the interior of the housing and a closed position for preventing external air and/or water from entering the enclosure through the exhaust port when the intake fan is not operating.

2. The equipment enclosure ofclaim 1 further comprising a filter positioned in the airflow path between the intake port and the equipment bay.

3. The equipment enclosure ofclaim 2 wherein the filter is a hydrophobic filter.

4. The equipment enclosure ofclaim 3 wherein there is no exhaust fan associated with the exhaust port.

5. The equipment enclosure ofclaim 4 wherein there is no hydrophobic filter associated with the exhaust port.

6. The equipment enclosure ofclaim 3 further comprising a particle filter positioned in the airflow path upstream of the hydrophobic filter.

7. The equipment enclosure ofclaim 3 wherein the housing includes a door having an opening extending therethrough, wherein the airflow path extends through the door opening and wherein the intake fan is mounted to the door over the door opening.

8. The equipment enclosure ofclaim 3 further comprising a controller configured to selectively operate the intake fan to maintain a defined temperature within the interior of the housing.

9. The equipment enclosure ofclaim 8 wherein the defined temperature is a function of an ambient air temperature on an external side of the enclosure.

10. The equipment enclosure ofclaim 8 wherein the defined temperature is a fixed temperature.

11. The equipment enclosure ofclaim 3 wherein the equipment enclosure is deployed in an outdoor environment and includes at least one item of outside plant equipment positioned in the equipment bay.

12. The equipment enclosure ofclaim 3 further comprising a heater.

13-23. (canceled)

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