Electronic device enclosures having improved ventilation to dissipate heat

Electronic device enclosures providing improved heat dissipation are described herein. An example enclosure for holding an electronic circuit board includes a housing having a first portion coupled to a second portion to form a cavity to hold the electronic circuit board. Each of the first and second portions comprises openings to direct convention airflow across opposing faces of the electronic circuit board at the same time. A baffle is coupled to the housing to substantially visually obscure the openings and to define a gap between the housing and the baffle to direct the convection airflow across the opposing faces of the electronic circuit board.

FIELD OF THE DISCLOSURE

This disclosure relates generally to enclosures and, more particularly, to electronic device enclosures having improved ventilation to dissipate heat.

BACKGROUND

Process control systems are widely used, for example, in factories and/or plants in which products are manufactured or processes are controlled (e.g., chemical manufacturing, power plant control, etc.). Most modern process control systems include smart field devices and other process control components that are communicatively coupled to each other and/or to one or more controllers, Ethernet switches, and/or other electronic devices.

Electronic devices include electronic components or circuitry (e.g., an electronic circuit board) disposed within a housing or enclosure. During operation, the electronic components can generate significant amounts of heat, which may cause the electronic components to overheat and become damaged or otherwise impaired. To prevent overheating of the electronic devices, the heat generated by electronic components should be properly dissipated via the enclosure. Proper heat dissipation can improve reliability and prevent premature damage and failure of the electronic devices and/or components.

SUMMARY

In one example, an enclosure for holding an electronic circuit board includes a body having a first face, a second face opposite the first face, and an exterior peripheral surface separating the first and second faces. The electronic circuit board is to be disposed between the first and second faces so that a first side of the electronic circuit board faces the first face and the second side of the electronic circuit board faces the second face. A first portion of the exterior peripheral surface includes at least one opening for at least one electrical connector to electrically couple the electronic circuit board to another electronic device. A second portion of the exterior peripheral surface includes a first air vent to be oriented in a downwardly facing direction and a third portion of the exterior peripheral surface includes a second air vent opposite the first air vent and which is to be oriented in an upwardly facing direction. A baffle is coupled to the body adjacent at least the second and third portions of the exterior peripheral surface such that the baffle is configured to direct airflow into the first air vent and out the second air vent. Also, the baffle is to be coupled adjacent the second and third portions of the exterior peripheral surface to at least partially visually cover the air vents.

In another example, an enclosure for holding an electronic circuit board includes a housing having a first portion coupled to a second portion to form a cavity to hold the electronic circuit board. Each of the first and second portions comprises openings to direct convection airflow across opposing faces of the electronic circuit board at the same time. A baffle is coupled to the housing to substantially visually obscure the openings and to define a gap between the housing and the baffle to direct the convection airflow across the opposing faces of the electronic circuit board.

In yet another example, an enclosure for holding an electronic circuit board includes a housing having a cavity to hold the electronic circuit board. The housing having first openings on a first side of the housing to be oriented in a downwardly facing direction and second openings on a second side of the housing to be oriented in an upwardly facing direction. A baffle is coupled to the housing and spaced from the openings to visually obscure the openings and to direct airflow into the first openings, adjacent opposing faces of the electronic circuit board at the same time, and out the second openings.

DETAILED DESCRIPTION

The example enclosures described herein may hold an electronic circuit board of an electronic device (e.g., an Ethernet switch). In particular, the example enclosures described herein provide improved ventilation to dissipate heat generated by an electronic device more efficiently. Ventilation is provided by the example enclosures via a natural convection and passive cooling configuration that does not require the use of fans, liquid cooling systems, heat sinks, etc. In this manner, the example enclosures described herein can be used to properly dissipate heat to improve the overall reliability and prevent premature damage and failure of electronic device components (e.g., an electronic circuit board) mounted within or held by the enclosures.

In one example, an enclosure described herein includes a housing having a cavity to hold one or more electronic circuit boards. The housing includes air vents or openings to direct convection or passive airflow across opposing faces of the electronic circuit board(s) at the same time. The enclosure also includes a baffle coupled to the housing to visually obscure the openings and to define a gap between the housing and the baffle to direct or channel the convection airflow across the opposing faces of the electronic circuit board. Also, the air vents are recessed relative to outer surfaces of the housing and the baffle at least partially covers the air vents to help prevent or substantially reduce the ingress of debris, dirt, air-borne particles, and/or other contaminates or objects to an interior surface of the enclosure via the air vents or openings.

Additionally, the example enclosure is shaped and/or sized to provide improved passive airflow (e.g., increased airflow velocity) as air flows between the air vents or openings (e.g., to provide a chimney effect or a stack effect). For example, the housing may be configured such that a height of the housing is larger than a width of the housing. The air vents are located adjacent the substantially vertical ends of the enclosure (e.g., adjacent top and bottom ends of an enclosure) to provide cross-ventilation across all surfaces of the electronic components disposed within the housing at the same time. In some examples, the housing may include a curved surface or profile to facilitate the channeling of air flow between the air vents.

In contrast, some known electronic devices may include heat sinks, fans, and/or liquid cooling systems to dissipate heat from one or more electronic devices. However, heat sinks, liquid cooling systems, fans, etc., significantly increase manufacturing costs. Additionally, such heat dissipation systems typically increase the overall physical or dimensional envelope or footprint of the enclosure. Further, in some instances, space may be limited. Thus, natural convection ventilation may be the only means available to dissipate heat from an electronic circuit board.

FIGS. 1A and 1Billustrate an example electronic module100described herein. Referring toFIGS. 1A and 1B, the example electronic module100described herein can be used, for example, with a process control system. For example, the electronic module100can be used to implement a network device such as, for example, an Ethernet switch. The example electronic module100may be communicatively coupled to a second electronic module101, a controller, and/or or any other device. In this example, the electronic module100includes an enclosure102that removably couples to a base104via a latching mechanism106. The base104includes ports108a-dsuch as, for example, a power port, a data transmission port, an uplink port, and/or any other suitable ports to receive power lines and/or transmission lines to communicate data to a desired location and/or device. The base104may be mounted within and/or to, for example, a cabinet, a rack, a field device, and/or any other suitable mounting surface(s).

The enclosure102provides an improved passive cooling or natural convection ventilation to provide more efficient dissipation of heat. In particular, as shown inFIG. 1B, the enclosure102may include air passages or vents110along a peripheral external surface112of the enclosure102to provide ventilation between the air passages or vents110. The enclosure102also includes a baffle or spine114to at least partially visually cover the air passages or vents110. Alternatively, the enclosure102may include an air passage or vent116along a body portion118of the enclosure102. A second baffle120may be coupled to the enclosure102to at least partially visually cover the air passage or vent116. The second baffle120may provide indicia122associated with a characteristic of the electronic module100. Although not shown, the air passage or vent116may be projected inwardly (e.g.,) recessed relative to the body portion118via a beveled edge124to provide a gap between the air passage or vent116and the second baffle120to enable air flow through the air passage or vent116. The enclosure102may be configured to include the air passages or vents110, the air passage or vent116and/or other air passages disposed along other portions of the external peripheral edge112and/or the body102.

FIGS. 2A-2Dillustrate another example enclosure200described herein that may be used to implement the example electronic module100ofFIGS. 1A and 1B. Referring toFIGS. 2A-2D, the example enclosure200includes a housing or body202having a cavity204to hold, for example, one or more electronic circuit boards206. The housing202includes a first or right face208and a second or left face210opposite the first face208. The housing202also includes an exterior peripheral surface212separating the first and second faces208and210.

In this example, a first electronic circuit board214ais electrically coupled to (e.g., via a connector) and disposed adjacent a second electronic circuit board214bto provide a smaller dimensional footprint. In other examples, the first electronic circuit board214amay not be electrically coupled to the electronic second circuit board214band may function independently from the second electronic circuit board214b. In yet other examples, more than two electronic circuit boards may be disposed within the housing202.

The first and second electronic circuit boards214aand214bare disposed within the housing202such that respective first sides216aand216bof the first and second electronic circuit boards214aand214bface the first face208of the housing202and respective second sides218aand218bof the first and second circuit boards214aand214bface the second face210of the housing202. The first and second electronic circuit boards214aand214bare disposed within the housing202such that a space220is defined between the first side216bof the second electronic circuit board214band the second side218aof the first electronic circuit board214a. Additionally, in this example, the first and second electronic circuit boards214aand214bare substantially vertically orientated when the electronic module100is in use.

In this example, the enclosure200includes racks, brackets or holders222and224a-bto retain the electronic circuit boards214a-bwithin the housing202. In other examples, the housing202may include pins to help retain the electronic circuit board(s)206within the housing202. A light bar226may be coupled to the electronic circuit board(s)206to provide indicator or status lights228(e.g., LED lights) to display the operational status of the electronic module100(FIGS. 1A and 1B). For example, one or more of the status lights228may be illuminated to indicate, for example, a power status, a speed status, a connection status, and/or any other operational status of the electronic module100and/or a network system to which the electronic module100is operatively coupled.

As shown inFIG. 2B, the enclosure200includes a rear portion230. The rear portion230includes at least one opening232and/or other connectors234to electrically couple the electronic circuit boards214a-bto, for example, the base104(FIGS. 1A and 1B) and/or other electronic devices. In yet other examples, the rear portion230may include communication ports, power supply ports, or any other suitable ports to receive, for example, data transmission lines or cables so that the base104is not required.

As noted above, the enclosure200provides an improved passive cooling or natural convection ventilation to provide more efficient dissipation of heat generated by the electronic circuit boards214a-bdisposed within the housing202. In particular, the housing202includes a first air vent238along a first portion240of the exterior peripheral surface212of the housing202and a second air vent242along a second portion244of the exterior peripheral surface212of the housing202to direct convection airflow across opposing faces (e.g., the first sides216a-band second sides218a-b) of the electronic circuit boards214a-b. Thus, the airflow is directed between the space220formed between the electronic circuit boards214a-band along respective interior portions or surfaces (e.g., of the opposing faces208and210) of the housing202at the same time.

In this example, the first air vent238is to be oriented in a downwardly facing direction and the second vent242is to be oriented in an upwardly facing direction and opposite the first vent238. As shown, the air vents238and242are adjacent the first and second faces208and210of the housing202. Additionally, the housing202is shaped and/or sized (e.g., has a greater height relative to its width) to provide improved air flow (e.g., increased airflow velocity) as the air flows between the first and second air vents238and242.

The enclosure200also includes a baffle or spine246coupled (e.g., mechanically coupled) to the housing202to be a structural member of the enclosure200. In general, the baffle246is coupled to the housing202adjacent at least the first portion240of the exterior peripheral surface212and the second portion244of the exterior peripheral surface212adjacent the respective first and second air vents238and242. When coupled to the housing202, the baffle246at least partially visually obscures or covers the first and second air vents238and242. The baffle246is coupled to the housing202such that the baffle246directs the convection airflow across the opposing faces of the electronic circuit board206. In other words, the baffle246is configured to direct airflow into the first air vent238, across the surfaces216a-b,218a-bof the electronic circuit boards214a-b, and out of the second air vent242.

In other examples, a third vent may be provided along a third portion (e.g., a front portion) of the exterior peripheral surface212of the housing202. The baffle may included openings (e.g., downwardly angled openings) to at least partially cover the third vent. In other examples, at least one of the first or second faces208and210may include another air vent to direct airflow adjacent a respective one of the sides (e.g.,216a-band218a-b) of the electronic circuit boards214a-b. Additionally, a second baffle (not shown) may be coupled to the first or second faces208and210to at least partially cover the other air vent (e.g., similar to the air vent116and the baffle120ofFIG. 1B).

FIG. 3illustrates an exploded view of the example enclosure200ofFIGS. 2A-2D. The housing202includes a first portion or panel302and a second portion or panel304. In this example, a latch release mechanism306is coupled to the baffle246to enable the enclosure200to be coupled to and/or released from, for example, the base104. The latch release mechanism306includes a rocking arm308, a button portion310, and a retaining clip312. The baffle246includes a slot or opening314to receive the rocking arm308, and the rocking arm308pivotally couples to the baffle246via a pivot316. The button portion310couples (e.g., via snap fit) to the rocking arm308and is retained adjacent a first end318of the rocking arm308via the retaining pin312. When the button portion310is depressed toward a surface320of the baffle246, the first end318of the rocking arm308rotates about the pivot316to actuate or release, for example, the latching mechanism106of the base104(FIGS. 1A and 1B). Also, in this example, the rear portion230(FIG. 2B) of the enclosure200(FIG. 2B) is a third portion or panel322. The third panel322couples to the first and second panels302and304and includes at least one opening324for at least one electrical connector to electrically couple the electronic circuit boards214a-b(FIGS. 2C-D) to at least one other electronic device.

FIGS. 4A and 4Bdepict the first and second panels302and304ofFIG. 3, respectively. Referring toFIGS. 4A and 4B, in this example, the first panel302includes grill or air vent portions402a-babout a peripheral edge404of the first panel302. The second panel304includes grill or air vent portions406a-babout a peripheral edge408of the second panel304. The grill portions402a-band406a-bproject inwardly relative to the respective first and second sides410and412via beveled edges414and416. Additionally, the grill portions402a-band406a-bprotrude or extend from the respective peripheral edges404and408of the first and second panels302and304. As shown, each of the grill portions402a-band406a-bincludes apertures418or slots420.

Although not shown, in other examples, the first panel302may be configured to only include the grill portion402ahaving at least one aperture418and the second panel304may be configured to only include the grill portion406bhaving at least one aperture418. In yet other examples, only the first panel302may include the grill portions402a-bhaving apertures418. In yet other examples, the first panel302and/or the second panel304may include additional grill portions having apertures418and/or slots420disposed along other portions of the respective peripheral edges404and408. For example, additional grill portions may be provided along a front portion436of the edges404and408.

In this example, the first and second panels302and304couple together via snap fit to define the housing202. As shown, the second panel304includes flexible members424having edges426and tapered portions428, and the first panel302includes receiving members430having apertures432. When coupled together, the receiving members430receive respective ones of the flexible members424such that the edges426of the flexible members424engage respective surfaces434adjacent the apertures432to couple the first and second panels302and304. In other examples, the first and second panels302and304may be coupled together via mechanical fasteners, chemical fasteners, and/or any other fastening mechanism(s). Each of the first and second panels302and304is made of a plastic material via, for example, injection molding or any other suitable manufacturing process(es). However, in other examples, the first and second panels302and304may be made of any other suitable material.

FIGS. 5A and 5Billustrate the example first and second panels302and304coupled together to define the housing202. When coupled together, the first panel302defines the first face208of the housing202and the second panel304defines the second face210of the housing202. Also, when the first and second panels302and304are coupled together, the grill portions402a-band406a-bmatably engage to define at least a part of the exterior peripheral surface212of the housing202separating the first and second faces208and210. In this example, the exterior peripheral surface212includes a first or top face or side502, a second or bottom face or side504, and a third or front face or side506.

When coupled together, the apertures418and/or the slots420(FIGS. 4A and 4B) of the first and second panels302and304provide openings508to define the first and second air vents238and242. More specifically, the housing202includes a first plurality of openings510ato be oriented in a first or downwardly facing direction and a second plurality of openings510bto be oriented in a second or upwardly facing direction opposite the first plurality of openings510a. The first plurality of openings510ais distributed in first and second parallel rows and the second plurality of openings510bis also distributed in third and fourth parallel rows. However, in other examples, the first plurality of openings510amay be oriented in a different direction and/or configuration than the second plurality of openings510b.

As shown, the first plurality of openings510ais adjacent the bottom face504of the exterior peripheral surface212of the housing202and the second plurality of openings510bis adjacent the top face502of the exterior peripheral surface212. Further, the rows of openings making up each of the plurality of openings510aand510bare adjacent respective ones of the faces208and210of the housing202. The first and second plurality of openings510aand510bprovide the first and second air vents238and242to enable airflow to pass through the housing202to provide a passive cooling or natural convection ventilation to cool the electronic circuit board(s)206(FIGS. 2C and 2D) disposed within the housing202. In other examples, the first plurality of openings510amay include a greater number of openings508than the second plurality of openings510b. In yet other examples, the openings508of the first plurality of openings510amay be sized larger than the openings508of the second plurality of openings510b, or the second plurality of openings510bmay be sized larger than the openings508of the first plurality of openings510a.

The front face506of the exterior peripheral surface212also includes openings512to receive, for example, the light bar226(FIG. 2D). A rear face514of the housing202includes at least one opening516to receive at least one electrical connector to electrically couple the electronic circuit board(s)206(FIGS. 2C and 2D) to at least one other electronic device. As described above, in this example, the rear face514of the housing202receives the third panel322(FIG. 3), which includes the opening or port324to electrically couple the electronic circuit board(s)206to at least one other electronic device.

FIG. 6illustrates the baffle246. In this example, the baffle246is depicted as a unitary band or spine structure. However, in other examples, the baffle246may be separate pieces or structures that couple to the housing202. In this example, the baffle246includes a top face602, a front face604and a bottom face606. As noted above, the top face602includes the slot314to receive the latch release mechanism306(FIG. 3). The baffle246also provides indicia associated with a characteristic of the electronic circuit board206. For example, the front face604includes a plurality of openings608to display the status lights228of the light bar226. Additionally, the front face604may include an opening610(e.g., a V-shaped opening) to receive an indicator light to indicate, for example, that electrical power is being supplied to the electronic module100(FIGS. 1A and 1B). The baffle246may also include a curved surface or profile612that may help channel the airflow through the housing202when the baffle246is coupled to the housing202.

Additionally, the baffle246includes protruding members or clips614(e.g., hook-like members) that engage (e.g., interlock) with portions of the housing202to mechanically couple the baffle246to the housing202via snap-fit. In other examples, the baffle246may be coupled to the housing202via mechanical fasteners, chemical fasteners, and/or any other suitable fastener(s). In this example, the baffle246is made of a metallic material. However, in other examples, the baffle246may be made of a plastic material, a plastic-metal laminate, and/or any other suitable material.

FIG. 7illustrates a side view of the enclosure200showing the baffle246coupled to the housing202. As shown, the housing202may include a curved portion or profile702between the first and second plurality of openings510aand510b. The curved portion702may facilitate or help channel the airflow between the first and second plurality of openings510aand510b. Also, when coupled to the housing202, the baffle246substantially surrounds or wraps around a substantial portion of the exterior peripheral surface212of the housing202. More specifically, the baffle246substantially surrounds the top face502, the front face506, and the bottom face504of the exterior peripheral surface212of the housing202. Thus, in this example, the baffle246does not cover the opening or rear face514of the housing202when the baffle246is coupled to the housing202. Additionally, the baffle246covers or at least partially visually obscures the plurality of openings510aand510bto provide a guard or shield, but does not inhibit airflow between the baffle246and the plurality of openings510aand510b.

FIG. 8is a schematic cross-sectional illustration of the example baffle246coupled to the housing202. As shown, the baffle246is mechanically coupled or captured between the first and second panels302and304when the first and second panels302and304are coupled together. When coupled to the housing202, the baffle246is spaced away from the first plurality of openings510aof the first air vent238and the second plurality of openings510bof the second air vent242to define a gap802between the baffle246and the housing202. The gap802enables airflow between the baffle246and the plurality of openings510aand510bas indicated by respective arrows804and806.

The gap802between the baffle246and the openings508enables the baffle246to direct convection airflow into the first air vent238across all internal surfaces of the housing202. More specifically, the baffle246directs airflow through the first air vent238adjacent the sides216a-band218a-b(e.g., opposing faces) of the electronic circuit board(s)206as indicated by arrows808at the same time and out of the second air vent242. Specifically, the first and second air vents238and242are spaced at opposite ends of the housing202to provide cross ventilation across the electronic circuit boards214a-b.

As noted above, the gap802is dimensioned to enable the baffle246to direct or facilitate the direction of airflow across the first and second sides216a-band218a-bof the electronic circuit boards214a-b. Additionally, a first edge810of the baffle extends beyond the grill portions402a-bof the first panel302adjacent the first face208of the housing202and a second edge812of the baffle246extends beyond the grill portions406a-bof the second panel304adjacent the second face210of the housing202. By recessing the grill portions402a-band406a-b, the edges810and812extend beyond the recessed portions402a-band406a-bso that the baffle246at least partially covers or shields and visually obscures the openings508of the housing202to prevent the ingress of debris, dirt, air-borne particles, and/or other contaminates or objects within the cavity204(e.g., the electronic circuit board206) of the housing202via the openings508. Also, when coupled to the housing202, the baffle246helps channel the air flow through the housing202between the first air vent238and the second air vent242.

In operation, electrical power is applied to the electronic circuit boards214a-bdisposed within the housing202. The status lights228indicate whether electrical power is provided to the electronic circuit boards214a-b. Also, the status lights228of the light bar226are visually displayed via the openings608of the baffle246when the baffle246is coupled to the housing202. During operation, the electronic circuit boards214a-bgenerate heat. The heat generated by the electronic circuit boards214a-bincreases the temperature of the air adjacent the electronic circuit boards214a-bwithin the housing202. In turn, the density of the warmer air is less when the temperature of the air increases relative to the surrounding air mass, causing the air to rise within the housing202. As the air temperature within the housing202increases, air flows between the openings508of the first air vent238and the openings508of the second air vent242.

More specifically, the baffle246directs the airflow through the first air vent238adjacent opposing faces of the electronic circuit boards214a-bat the same time as indicated by arrows808. In this manner, airflow is provided to substantially all sides (e.g., the first sides216a-band the second sides218a-b) of the electronic circuit boards214a-bto substantially prevent a hot spot condition that may otherwise occur if the airflow is not distributed (e.g., evenly) across all surfaces of the electronic circuit boards214a-b. Also, the baffle246channels the air flow such that the warmer air exiting the second air vent242draws or pulls the cooler air from the first air vent238providing a chimney or stack effect. For example, a height814of the housing202may be sized significantly larger than a width816of the housing202. In other words, the housing is configured (e.g., shaped and sized) and/or the baffle246is positioned to duct the warmer air rising toward the second air vent242more rapidly and efficiently (e.g., a passive cooling configuration).

Although not shown, in other examples, forced convection airflow may be provided toward or adjacent the first air vent238and/or the second air vent242. Such forced convection may be provided via, for example, a cooling fan. In yet other examples, heat sinks may be disposed within the housing202to further improve dissipation of the heat from within the housing202. In other words, the airflow provided through the housing202between the first and second air vents238and242may flow across heat sinks disposed within the housing202and/or the electronic circuit board206to further dissipate heat from within the housing202.