Illuminated viewing systems for enclosures

An enclosure disposed in an ambient environment can include at least one wall that forms a cavity. The enclosure can also include at least one electrical device disposed within the cavity. The enclosure can further include at least one illuminated viewing system disposed in the at least one wall. The at least one illuminated viewing system can include a window disposed in the at least one wall. The at least one illuminated viewing system can also include at least one light source assembly that directs light within the cavity in which the at least one electrical device is disposed.

TECHNICAL FIELD

The present disclosure relates generally to enclosures, and more particularly to systems, methods, and devices for enclosures with illuminated window systems.

BACKGROUND

Enclosures, such as electrical enclosures, are used in a number of applications (e.g., commercial, industrial, residential) and have a number of different shapes, sizes, and configurations. Sometimes, such enclosures contain one or more pieces of equipment or devices. Such equipment can be electrical, mechanical, electronic, electro-mechanical. At times, it is necessary to visually inspect the equipment within an enclosure. Opening and closing these enclosures can be time-consuming, can present electrical shock hazards, can require prior de-energization of the enclosure, can require declassification of a hazardous location environment, and/or can present any of a number of other obstacles. As a result, inspection of equipment within such enclosures can be difficult or even discouraged because of the extra time and work involved. Some enclosures can include a viewing window, but such viewing window can be difficult to look through and may not be positioned properly to allow certain equipment within the enclosure to be viewed.

SUMMARY

In general, in one aspect, the disclosure relates to an enclosure disposed in an ambient environment. The enclosure can include at least one wall that forms a cavity. The enclosure can also include at least one electrical device disposed within the cavity. The enclosure can further include at least one illuminated viewing system disposed in the at least one wall. The at least one illuminated viewing system of the enclosure can include a window disposed in the at least one wall, and at least one light source assembly that directs light within the cavity in which the at least one electrical device is disposed.

DETAILED DESCRIPTION

In general, example embodiments provide systems, methods, and devices for enclosures with illuminated window systems. While many of the example enclosures with illuminated window systems described herein are located in hazardous (e.g., explosive) environments, such enclosures can be located in other environments that are not considered hazardous. A user may be any person that interacts with enclosures. Examples of a user may include, but are not limited to, an engineer, an electrician, an instrumentation and controls technician, a mechanic, an operator, a consultant, a contractor, and a manufacturer's representative.

The example illuminated window systems described herein can be used as a new system for enclosures that do not have windows, as a retrofit system for enclosures that have windows that are not illuminated, and/or for entries that can be fitted with windows. The illuminated window systems for enclosures (or components thereof) described herein can be made of one or more of a number of suitable materials to allow the enclosures to meet certain standards and/or regulations while also maintaining durability in light of the one or more conditions under which the enclosures, including the example illuminated window systems, can be exposed. Examples of such materials can include, but are not limited to, aluminum, stainless steel, fiberglass, glass, plastic, ceramic, and rubber.

Example illuminated window systems for enclosures, or portions thereof, described herein can be made from multiple pieces that are mechanically coupled to each other. In such a case, the multiple pieces can be mechanically coupled to each other using one or more of a number of coupling methods, including but not limited to epoxy, welding, fastening devices, compression fittings, mating threads, and slotted fittings. One or more pieces that are mechanically coupled to each other can be coupled to each other in one or more of a number of ways, including but not limited to fixedly, hingedly, removeably, slidably, and threadably.

Components and/or features described herein can include elements that are described as coupling, mounting, fastening, securing, or other similar terms. Such terms are merely meant to distinguish various elements and/or features within a component or device and are not meant to limit the capability or function of that particular element and/or feature. For example, a feature described as a “coupling feature” can couple, mount, secure, fasten, abut against, and/or perform other functions aside from merely coupling.

A coupling feature (including a complementary coupling feature) as described herein can allow one or more components and/or portions of an example illuminated window to become mechanically coupled, directly or indirectly, to another portion of the illuminated window and/or an enclosure. A coupling feature can include, but is not limited to, a portion of a hinge, an aperture, a recessed area, a protrusion, a clamp, a slot, a spring clip, a tab, a detent, and mating threads. One portion of an enclosure can be coupled to a component of an example illuminated window systems by the direct use of one or more coupling features.

In addition, or in the alternative, a portion of an example illuminated window can be coupled to a component of an enclosure using one or more independent devices that interact with one or more coupling features disposed on a component of the illuminated window or other component of the enclosure. Examples of such devices can include, but are not limited to, a pin, a hinge, a fastening device (e.g., a bolt, a screw, a rivet), a clamp, and a spring. One coupling feature described herein can be the same as, or different than, one or more other coupling features described herein. A complementary coupling feature as described herein can be a coupling feature that mechanically couples, directly or indirectly, with another coupling feature.

Further, if a component of a figure is described but not expressly shown or labeled in that figure, the label used for a corresponding component in another figure can be inferred to that component. Conversely, if a component in a figure is labeled but not described, the description for such component can be substantially the same as the description for the corresponding component in another figure. The numbering scheme for the various components in the figures herein is such that each component is a three or four digit number and corresponding components in other figures have the identical last two digits.

In addition, a statement that a particular embodiment (e.g., as shown in a figure herein) does not have a particular feature or component does not mean, unless expressly stated, that such embodiment is not capable of having such feature or component. For example, for purposes of present or future claims herein, a feature or component that is described as not being included in an example embodiment shown in one or more particular drawings is capable of being included in one or more claims that correspond to such one or more particular drawings herein.

In the foregoing figures showing example embodiments of illuminated window systems for enclosures, one or more of the components shown may be omitted, repeated, and/or substituted. Accordingly, example embodiments of illuminated window systems for enclosures should not be considered limited to the specific arrangements of components shown in any of the figures. For example, features shown in one or more figures or described with respect to one embodiment can be applied to another embodiment associated with a different figure or description. As a specific example, a sensor device can be used in an example embodiment described below, even though no sensor device is shown or described for that particular embodiment.

As defined herein, an enclosure is any type of cabinet or housing inside of which is disposed one or more devices (e.g., mechanical devices, electrical devices, electronic devices, electromechanical devices). Examples of such devices can include, but are not limited to, variable frequency drives (VFDs), controllers, relays (e.g., solid state, electro-mechanical), contactors, circuit breakers, switches, transformers, inverters, converters, fuses, electrical cables, thermo-electric coolers (TECs), enclosure walls, heating elements, air moving devices (e.g., fans, blowers), terminal blocks, motor stators, wire nuts, and electrical conductors. Examples of an enclosure can include, but are not limited to, an electrical connector, a junction box, a motor control center, a breaker cabinet, an electrical housing, a conduit, a control panel, an electrical receptacle, a lighting panel, a lighting device, a motor housing, a relay cabinet, an indicating panel, and a control cabinet.

For purposes of clarification, the enclosures described herein house at least one electrical device and are used in commercial or industrial processes. As a result, certain devices that might, in a very general and broad sense, be considered an “enclosure” would not be considered an enclosure for purposes of example embodiments described herein. Examples of such devices that are not considered an enclosure as applied for use with example embodiments described herein can include, but are not limited to, a display cabinet, a china hutch, a trophy case, a bulletin board case, a refrigerator, a freezer, a toaster oven, a conventional oven, and a microwave oven.

While all of these examples may include an electrical device, those electrical devices are housed in a separate compartment for the purpose of operating the device itself. For example, a refrigerator has a compressor, housed in a separate space from where food is stored, that runs to operate the refrigerator. Generally speaking, all of the enclosures with which example embodiments can be used have disposed therein at least one electrical device that is used to operate some other device, component, or process that is external to the enclosure.

Example embodiments are designed to provide illumination within an enclosure so that one or more devices disposed within the enclosure can be viewed through a window in a wall of the enclosure. In this way, the one or more devices can be viewed by a user without the user having to open the enclosure. Further, a user can inspect the interior of the enclosure for signs of corrosion, moisture accumulation, and other conditions that require maintenance. In addition, example embodiments can be used to verify the position and/or operation of a device within the enclosure. For example, example embodiments can be used to allow a user to verify the position of a contactor inside an enclosure, to verify that the blades of a switch (located inside an enclosure) have disengaged with the movement of the switch handle mounted in the door of the enclosure, or to verify whether a fuse located inside an enclosure has blown. Example embodiments can operate continuously, at regular intervals, on-demand (e.g., as a user approaches an example window of an enclosure), and/or according to some other schedule.

In certain example embodiments, enclosures with which example illuminated window systems are integrated are subject to meeting certain standards and/or requirements. For example, the National Electric Code (NEC), the National Electrical Manufacturers Association (NEMA), the International Electrotechnical Commission (IEC), and the Institute of Electrical and Electronics Engineers (IEEE) set standards as to electrical enclosures, wiring, and electrical connections. Enclosures that include example illuminated window systems described herein meet such standards when required. In some (e.g., PV solar) applications, additional standards particular to that application may be met by the enclosures with which example illuminated window systems are integrated.

For example, the example illuminated window systems, when integrated with an electrical enclosure, can allow the electrical enclosure to meet the NEMA 4X standard. In such a case, the electrical enclosure is constructed to provide a degree of protection to components (e.g., devices) disposed within the electrical enclosure against, at least, corrosion, falling dirt, rain, sleet, snow, ice, windblown dust, splashing water, and hose-directed water. As a specific example, an electrical enclosure with a NEMA 4X rating can provide protection with respect to harmful effects on equipment disposed within the electrical enclosure due to ingress of water. Thus, an example illuminated window that is mechanically coupled to such an electrical enclosure must also meet these standards.

An enclosure that includes an example illuminated window can be located in any type of environment (e.g., indoors, outdoors, under water, in a climate controlled room). In addition, or in the alternative, enclosures with an example illuminated window can be located in hazardous and/or marine environments. As defined herein, a hazardous location is any location where the enclosure can be exposed to extreme conditions. Extreme conditions can include, but are not limited to, high temperatures, low temperatures, temperature fluctuations, corrosion, humidity, chemicals, chemical vapors, vibrations, and dust. More information about hazardous locations and hazardous location enclosures can be found, for example, in Articles 500-506 and Articles 510-517 of the National Electric Code, which is incorporated herein by reference.

Examples of a hazardous location in which example embodiments can be used can include, but are not limited to, an airplane hangar, a drilling rig (as for oil, gas, or water), a production rig (as for oil or gas), a refinery, a chemical plant, a power plant, a mining operation, and a steel mill. A hazardous environment can include an explosive environment, which would require an enclosure with an example illuminated window to meet one or more requirements, including but not limited to maintaining flame paths.

An explosion-proof enclosure is a type of hazardous location electrical enclosure. In one or more example embodiments, an explosion-proof enclosure (also known as a flame-proof enclosure) is an electrical enclosure that is configured to contain an explosion that originates inside the enclosure. Further, the explosion-proof enclosure is configured to allow gases from inside the explosion-proof enclosure to escape across joints (also called gaps herein) of the explosion-proof enclosure and cool as the gases exit the explosion-proof enclosure. The joints are also known as flame paths and exist where two surfaces meet and provide a path, from inside the explosion-proof enclosure to outside the explosion-proof enclosure, along which one or more gases may travel. A joint may be a mating of any two or more surfaces. Each surface may be any type of surface, including but not limited to a flat surface, a threaded surface, and a serrated surface.

In one or more example embodiments, an explosion-proof enclosure is subject to meeting certain standards and/or requirements. For example, NEMA sets standards with which an electrical enclosure must comply in order to qualify as an explosion-proof enclosure. Specifically, NEMA Type 7, Type 8, Type 9, and Type 10 enclosures set standards with which an explosion-proof enclosure within certain hazardous locations must comply. For example, a NEMA Type 7 standard applies to electrical enclosures constructed for indoor use in certain hazardous locations. Hazardous locations may be defined by one or more of a number of authorities, including but not limited to the National Electric Code (e.g., Class 1, Division I) and UL (e.g., UL 1203). For example, a Class 1 hazardous area under the National Electric Code is an area in which flammable gases or vapors may be present in the air in sufficient quantities to be explosive.

As a specific example, NEMA standards for an explosion-proof enclosure of a certain size or range of sizes (e.g., greater than 100 in3) may require that in a Group B, Division 1 area, any flame path of an explosion-proof enclosure must be at least 1 inch long (continuous and without interruption), and the gap between the surfaces cannot exceed 0.0015 inches. Standards created and maintained by NEMA may be found at www.nema.org/stds and are hereby incorporated by reference.

Example embodiments of illuminated window systems for enclosures will be described more fully hereinafter with reference to the accompanying drawings, in which example embodiments of illuminated window systems for enclosures are shown. Illuminated window systems for enclosures may, however, be embodied in many different forms and should not be construed as limited to the example embodiments set forth herein. Rather, these example embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of illuminated window systems for enclosures to those of ordinary skill in the art. Like, but not necessarily the same, elements (also sometimes called components) in the various figures are denoted by like reference numerals for consistency.

Terms such as “first”, “second”, “top”, “bottom”, “side”, “width”, “length”, “within”, “inner”, and “outer” are used merely to distinguish one component (or part of a component or state of a component) from another. Such terms are not meant to denote a preference or a particular orientation, and are not meant to limit embodiments of illuminated window systems for enclosures. In the following detailed description of the example embodiments, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to one of ordinary skill in the art that the invention may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.

FIGS. 1 and 2show an explosion-proof enclosure100(a specific type of enclosure) currently known in the art. Referring now toFIGS. 1 and 2, the explosion-proof enclosure100is shown in a closed position inFIG. 1and an open position inFIG. 2. The enclosure100is disposed in an ambient environment111(e.g., a hazardous environment). In the closed position, the enclosure cover102is secured to the enclosure body124. The enclosure body124has at least one wall125that forms a cavity207. In addition, the enclosure cover102has at least one wall103. There are a number of devices110(e.g., indicating lights196, electrical conductors209, a variable frequency drive (VFD)206, a switch288, a relay215, a terminal block213) disposed on a wall (e.g., wall125, wall103) and/or disposed within the cavity207of the enclosure100.

At least one of the devices110within the cavity207of the enclosure100is an electrical device. An electrical device is any device that uses electricity to operate. Examples of an electrical device can include, but are not limited to, a VFD, a relay, a motor, a controller, a contactor, a transformer, an inductor, a resistor, a fuse, an inverter, a switch, a breaker, and an indicating light. Example embodiments described herein are used to allow a user to view inside an enclosure (e.g., enclosure100) that contains at least one electrical device.

The enclosure cover102can be secured to the enclosure body124by a number of fastening devices118located at a number of points around the perimeter of the enclosure cover102. In one or more example embodiments, a fastening device118may be one or more of a number of fastening devices, including but not limited to a bolt (which may be coupled with a nut), a screw (which may be coupled with a nut), and a clamp. In addition, one or more optional hinges117can be secured to one side of the enclosure cover102and a corresponding side of the enclosure body124so that, when all of the fastening devices118are removed, the enclosure cover102may swing outward (i.e., an open position) from the enclosure body124using the one or more hinges117. In one or more example embodiments, there are no hinges, and the enclosure cover102can be completely separated from the enclosure body124when all of the fastening devices118are removed.

The enclosure cover102and the enclosure body124may be made of any suitable material, including metal (e.g., alloy, stainless steel), plastic, some other material, or any combination thereof. The enclosure cover102and the enclosure body124may be made of the same material or different materials. In one or more example embodiments, on the end of the enclosure body124opposite the enclosure cover102, one or more mounting brackets123are affixed to the exterior of the enclosure body124to facilitate mounting the enclosure100. Using the mounting brackets123, the enclosure100may be mounted to one or more of a number of surfaces and/or elements, including but not limited to a wall, a control cabinet, a cement block, an I-beam, and a U-bracket.

The enclosure cover102includes at least one wall103that can optionally include one or more features that allow for user interaction while the enclosure100is sealed in the closed position. As shown inFIG. 1, one or more devices110(e.g., indicating lights196) may be located (disposed) on the wall103of the enclosure cover102. The wall103of the enclosure cover102may also include (have disposed therein) a switch handle112(a type of mechanical device, which can be considered a device110because the switch handle112is coupled to an electrical device110, as discussed below) that allows a user to operate a switch (shown inFIG. 2below) located inside the explosion-proof enclosure100while the explosion-proof enclosure110is closed. Each position (e.g., OFF, ON, HOLD, RESET) of the switch may be indicated by a switch position indicator114positioned adjacent to the switch handle112on the outer surface of the wall103of the enclosure cover102. A switch associated with the switch handle112and the switch position indicator114may be used to electrically and/or mechanically isolate, and/or change the mode of operation of, one or more components inside or associated with the explosion-proof enclosure100.

There can be one or more conduits105that are coupled to a wall125of the body124of the explosion-proof enclosure100. Each conduit105can have one or more electrical conductors (e.g., electrical cables) disposed therein, where one end of the electrical conductors are electrically coupled to one or more electrical devices110disposed within the explosion-proof enclosure100, as shown below with respect toFIG. 2.

FIG. 2shows a front perspective view of an example of the interior of the explosion-proof enclosure100ofFIG. 1. Referring toFIGS. 1 and 2, the explosion-proof enclosure100is in the open position because the enclosure cover102is not secured to the enclosure body124. The hinges117attached to the left side of the enclosure body124are also attached to the left side of the enclosure cover102, which is swung outward from the enclosure body124. Because the explosion-proof enclosure100is in the open position, the components of the explosion-proof enclosure100are visible to a user.

As described above with respect toFIG. 1, the enclosure body124includes two or more mounting brackets123. In addition, in one or more example embodiments, the enclosure body124includes an enclosure engagement surface208(also called a flange), against which an enclosure engagement surface211(also called a flange) of the enclosure cover102abuts against when the explosion-proof enclosure100is in the closed position. A number of coupling features220(in this case, apertures) are shown around the enclosure engagement surface208, where each of the coupling features220are configured to receive a coupling feature118(in this case, a fastening device, such as a bolt) that traverses through corresponding coupling features (e.g., apertures) in the enclosure cover102.

In one or more example embodiments, the explosion-proof enclosure100ofFIG. 2includes a mounting plate295that is affixed to the back of the inside of the explosion-proof enclosure100. The mounting plate295may be configured to receive one or more components (e.g., electrical devices110, mechanical devices) such that the one or more components are affixed to the mounting plate295. The mounting plate295may include one or more apertures configured to receive coupling features (e.g., bolts) that may be used to affix a component to the mounting plate295. The mounting plate295may be made of any suitable material, including but not limited to the material of the enclosure body124. In one or more example embodiments, some or all of the one or more components may be mounted directly to an inside wall of the explosion-proof enclosure100rather than to the mounting plate295.

In this case, the electrical devices110mounted to the mounting plate295within the cavity207of the explosion-proof enclosure100include a VFD206, a switch288, a relay215, and a terminal block213. The switch288can include a switch coupling219that couples to a switch handle shaft217that extends from the switch handle112when the explosion-proof enclosure is in the closed position. Electrical conductors209are used to electrically couple one electrical device110to at least one other electrical device110within the cavity207of the explosion-proof enclosure100. Each conduit105is disposed within an entry hole201disposed in the bottom wall125of the enclosure body124of the explosion-proof enclosure100.

FIG. 3shows an example of an enclosure300with a window390currently known in the art. Referring toFIGS. 1-3, the enclosure300ofFIG. 3has a number of features that are substantially similar to corresponding features of the enclosure100ofFIGS. 1 and 2. For example, the enclosure300ofFIG. 3includes a number of mounting brackets323disposed on the enclosure body324, a number of hinges317coupled to a wall325of the enclosure body324and that hingedly couple the enclosure cover302to the enclosure body324, and a number of devices310(in this case, indicating lights, switches, and pushbuttons) mounted on the wall303of the enclosure cover302.

The enclosure300ofFIG. 3is shown in the closed position, with the enclosure cover302secured to the enclosure body324using a number of fastening devices318. The viewing window390of the enclosure300in this case is disposed in an aperture that traverses the wall303of the enclosure cover302. The window390in this case includes a lens391that is secured within an aperture in the wall303of the enclosure cover302using a frame392. The lens391in this case is circular in shape when viewed from the front of the enclosure300.

While the lens391can provide a view of the cavity of the enclosure300to a user while the enclosure300is in the closed position, there are often problems presented to a user when this occurs. The enclosure300often does not have any sources of light within the cavity, and even if sources of light (e.g., indicating lights) do exist, they do not generate enough lumens to allow a user to see through the lens391into the cavity of the enclosure300.

As a result, a user often uses a source of light (e.g., a flashlight) external to the enclosure300. This solution also poses a number of problems that prevents the user from viewing the devices within the cavity of the enclosure300. The lens391of the window390is often thick and/or made of a material has some degree of opaqueness. As a result, directing a light source assembly from the ambient environment311(outside the enclosure300) through the lens391often results in much of the light generated by the light source assembly being reflected back from the lens391. In addition, a flashlight or other light source used in a hazardous environment needs to be explosion-proof, which adds to the size and weight of the flashlight or other light source, making the flashlight or other light source difficult to handle and operate.

In other words, without having a light source assembly within the lens (e.g., lens391) of a window (e.g., window390) and/or within the cavity of an enclosure (e.g., enclosure300), a user often cannot view devices within the cavity through the lens of the window in enclosures currently known in the art. Examples of other enclosures having windows currently known in the art can be found in U.S. Provisional Patent Application No. 62/349,512, entitled “Visual Arrangements In Sealing Fittings For Conduit Systems; Enclosures; and Methods”, the entire contents of which are hereby incorporated herein.

FIGS. 4-8show enclosures with illuminated window systems in accordance with certain example embodiments. Specifically,FIG. 4shows a partial cross-sectional side view of an enclosure400with an example illuminated viewing system480.FIG. 5shows a partial cross-sectional side view of an enclosure500with an example illuminated viewing system580.FIG. 6shows a partial cross-sectional front view of an enclosure600with an example illuminated viewing system680.FIG. 7shows a partial cross-sectional side view of an enclosure700with an example illuminated viewing system780.FIG. 8shows a front view of an open enclosure800(with the cover detached from the enclosure body824) with an example illuminated viewing system880.

Example illuminated window systems can include one or more of a number of features, including but not limited to a lens, a sealing member, a light source assembly, a power source, a switch, a sensor, and an optical feature. Referring toFIGS. 1-8, the example illuminated viewing system480of the enclosure400ofFIG. 4includes a window490disposed within an aperture in the wall403of the enclosure cover402, as was the case in the example shown inFIG. 3above.

In this example, the window490includes a lens491, a transition layer482, a sealing member465, and a distal layer483. The transition layer482abuts against the distal end of the lens491and has a height (in this case, from the bottom ofFIG. 4to the top ofFIG. 4) that is slightly less than the height of the lens491. The distal layer483abuts against the distal end of the transition layer482and has a height that is greater than the height of the lens491. In this way, the proximal side of the outer perimeter of the distal layer483abuts against the inner surface of the wall403of the enclosure cover402adjacent to the aperture in which the lens491is disposed.

The window490can be made from a single piece, as from a mold. For example, the window490can be a molded from a polymer into a monolithic window. When made from a single piece, the various layers (e.g., transition layer482, distal layer483) of the window490described above can be undercuts and overhangs. Alternatively, the window490can be made from multiple pieces that are coupled (e.g., using epoxy, fused) to each other. These various layers are optional features of a window490. In this case, the optional sealing member465(e.g., a gasket, an o-ring, silicone) is disposed between the lens491, the transition layer482, and the distal layer483. The sealing member465helps provide an environmental seal, as can be required when the ambient environment411in which the enclosure400is located is a hazardous environment.

The window490can be coupled to the wall403of the enclosure cover402in any of a number of ways. In this case, the outer perimeter along the side of the lens491has mating threads484disposed thereon, and these mating threads484complement mating threads427disposed along the portion of the wall403of the enclosure cover402that forms the aperture in which the lens491is disposed. In such a case, the lens491is circular when viewed from outside the enclosure400. When the enclosure400is an explosion-proof enclosure, a flame path469is formed between mating threads427and mating threads484. Because of the mating thread configuration for securing the window490to the enclosure cover402in this case, use of a frame (e.g. frame392ofFIG. 3) is optional.

The illuminated viewing system480ofFIG. 4also includes one or more sensors460that detects the presence of a user proximate to the window490outside the enclosure400. The sensor460(sometimes called a sensor module460or a sensor device460) can be any type of sensing device that measure one or more parameters. Examples of types of sensors460can include, but are not limited to, a passive infrared sensor, a photocell, a pressure sensor, a proximity sensor, a noise sensor, a voice detector, an ultrasound sensor, an image capture device (e.g., a camera), a RFID reader, an air flow monitor, a gas detector, a finger print reader, a retina scanning device, and a resistance temperature detector. A parameter that can be measured by a sensor460can include, but is not limited to, motion, sound, a voice, an identification code (for example, an employee ID number on an employee ID badge), occupancy of a space, body temperature, gesture or other motion, and a biological identifier (e.g., fingerprint, retina image).

In some cases, the parameter or parameters measured by a sensor460can be used to operate one or more light source assemblies442of the illuminated viewing system480. For example, if a sensor460measures a parameter, or measures a value of a parameter that falls within a range of values, then one or more light source assemblies442illuminate, directing light444to one or more devices410(e.g., VFD406, circuit breaker429) within the cavity407of the enclosure400. In this example, the devices410(specifically, the VFD406and the circuit breaker429) are mounted on a back wall425of the enclosure body424. In some cases, one or more components of an example illuminated viewing system480can be considered a device410.

In certain example embodiments, optional optical device478can be used in conjunction with a sensor460. In such a case, the optical device478can be used to control the spatial range (e.g., field of view, distance, direction) from which the sensor460can read in the ambient environment411. Put another way, the optical device478can shape the beam or other source of energy used by the sensor460to measure a parameter in the ambient environment411.

The optical device478can have one or more of any of a number of characteristics (e.g., concave shape, convex shape, asymmetric, symmetric, random, a Fresnel lens configuration), Further, the optical device478can be attached to (e.g., adhered) or integral with one or more components (e.g., sensor460, lens491) of the illuminated viewing system480(or other parts of the enclosure400) in any of a number of ways. For example, the optical device478can be integral with the sensor460. As another example, as in this case, the optical device478can be adhered (e.g., using epoxy) to the outer surface of the lens491exposed to the ambient environment.

Each sensor460can be coupled to, or can include, a switch470. A switch470has an open state and a closed state (position). In the open state, the switch470creates an open circuit, which prevents the power supply440from delivering power to one or more of the light source assemblies442. In the closed state, the switch470creates a closed circuit, which allows the power supply440to deliver power to one or more of the light source assemblies442. In certain example embodiments, the position of each switch470is controlled by and/or based on input from a sensor460. Each switch470can be any type of device that changes state or position (e.g., opens, closes) based on certain conditions. Examples of a switch470can include, but are not limited to, a transistor, a dipole switch, a relay contact, a resistor, and a NOR gate.

Each switch470can be coupled to, or can be integrated with, a power supply440. In certain example embodiments, the power supply440of the example illuminated viewing system480receives power (e.g., primary power, secondary power) from an external source (e.g., a wall outlet, an energy storage device, a power source within the cavity407of the enclosure400). The power supply440uses the power it receives to generate and provide power (called also final power herein) to one or more of the light source assemblies442. The power supply440can also provide power to one or more other components of the illuminated viewing system480, including but not limited to a sensor460and a switch.

The power supply440can be called by any of a number of other names, including but not limited to a driver, a LED driver, and a ballast. The power supply440can include one or more of a number of single or multiple discrete components (e.g., transistor, diode, resistor), and/or a microprocessor. The power supply440may include a printed circuit board, upon which the microprocessor and/or one or more discrete components are positioned, and/or a dimmer.

The power supply440can include one or more components (e.g., a transformer, a diode bridge, an inverter, a converter) that receives power (for example, through an electrical cable) and generates final power of a type (e.g., alternating current, direct current) and level (e.g., 12V, 24V, 120V) that can be used by the light source assemblies442and/or other components of the illuminated viewing system480. In some cases, the power supply440can be a source of power in itself. For example, the power supply440can be an energy storage device (e.g., a battery, a supercapacitor), a localized photovoltaic power system, or some other source of independent power. In certain example embodiments, a sensor460can include an energy storage device (e.g., a battery) that is used to provide power, at least in part, to some or all of the rest of the sensor460.

The one or more light source assemblies442of the example illuminated viewing system480emit light when they receive the appropriate power and/or control signals from the power supply440. A light source assembly442can include one or more components, including but not limited to a local control module, a light engine, a heat sink, an electrical conductor or electrical cable, a light source (e.g., a light bulb, a LED), a substrate, a terminal block, and a circuit board. A light source assembly442can use any of a number of lighting technologies, including but not limited to light-emitting diode (LED), incandescent, fluorescent, halogen, and sodium vapor.

In this case, the example illuminated viewing system480also includes an optional optical device475. Here, the optical device475is disposed within the cavity407of the enclosure400and is disposed on the distal surface of the distal layer483. Further, the optical device475is disposed adjacent to the light source assembly442and is designed to manipulate (e.g., refract, focus, direct) the light444emitted by the light source assembly442so that a user, when looking through the lens491of the window490, can better view the devices410within the cavity407of the enclosure400. The presence of one optional optical device (e.g., optional optical device475) is independent of another optional optical device (e.g., optional optical device478).

The sensor460, the switch470, the power supply440, and the light source assembly442can be discrete components of the example illuminated viewing system480, as shown inFIG. 4. Alternatively, one or more of the sensor460, the switch470, the power supply440, and/or the light source assembly442can be combined with another component of the example illuminated viewing system480.

A sensor460can be located within, in, and/or outside the enclosure400. For example, in this case, the sensor460is disposed within the lens491. Similarly, a switch470can be located within, in, and/or outside the enclosure400. For example, in this case, the switch470is disposed within the lens491, adjacent to the sensor460. Further, the power supply440can be located within, in, and/or outside the enclosure400. For example, in this case, the power supply440is disposed within the lens491, adjacent to the switch470. In addition, one or more of the light source assemblies442can be located within and/or in, the enclosure400. For example, in this case, the light source assembly442is disposed within the lens491, adjacent to the power supply440.

When the enclosure400is located in a hazardous environment, the sensor460and/or other components of the example illuminated viewing system480can be intrinsically safe. As used herein, the term “intrinsically safe” refers to a device (e.g., a sensor460described herein) that is placed in a hazardous environment. To be intrinsically safe, the component of the example illuminated viewing system480uses a limited amount of electrical energy so that sparks cannot occur from a short circuit or failures that can cause an explosive atmosphere found in hazardous environments to ignite. A safety barrier is commonly used with an intrinsically safe device, where the safety barrier limits the amount of power delivered to the sensor or other component of the example illuminated viewing system480to reduce the risk of explosion, fire, or other adverse condition or event that can be caused by high amounts of power in the hazardous environment. An adverse condition or event can also be an abnormal condition that is not potentially catastrophic in nature.

Referring now toFIG. 5, the enclosure500ofFIG. 5is substantially the same as the enclosure400ofFIG. 4, except as described below. For example, the enclosure500ofFIG. 5includes an enclosure body524coupled to an enclosure cover502and is located in an ambient environment511. A window590of an illuminated viewing system580is disposed in a wall503of the enclosure cover502. Specifically, mating threads584disposed on the outer surface of the lens591of the window590couple to mating threads527that form an aperture in the wall503of the enclosure cover502, forming a flame path569between the enclosure cover502and the window590. Also, the window590includes a lens591, a transition layer582, a sealing member, and a distal layer583.

In this case, there is no optical device (e.g., optical device475) adjacent to the light source assembly542. Instead, there is a different optical device577disposed within the cavity507of the enclosure500and disposed on the distal surface of the distal layer583of the window590. Further, the optical device575covers most, if not all, of the height of the lens591and is designed to manipulate (e.g., focus, redirect) the view of a user when looking through the lens591of the window590. In this way, the user can better view the devices510(in this case, a VFD506and a circuit breaker529) disposed within the cavity507of the enclosure500when the light544emitted by the light source assembly542is directed to the devices510within the cavity507of the enclosure500. In this case, the VFD506and the circuit breaker529are mounted on a back wall525of the enclosure body524.

Further, the switch570, the power supply540, and the light source assembly542are disposed within the cavity507of the enclosure500rather than disposed within the lens591of the window590. The sensor560, which is still disposed within the lens591of the window590, is coupled to the switch570, the power supply540, and the light source assembly542using one or more electrical conductors509. Alternatively, the sensor560can be coupled to the switch570, the power supply540, and/or the light source assembly542wirelessly, such as through the use of inductive power transfer.

Referring now toFIG. 6, the enclosure600ofFIG. 6is substantially the same as the enclosure400ofFIG. 4or the enclosure500ofFIG. 5, except as described below. For example, the enclosure600ofFIG. 6includes an enclosure body624and is located in an ambient environment611. While the devices610disposed within the cavity607of the enclosure600are a VFD606and a circuit breaker629, in this case the VFD606and the circuit breaker629are mounted on a side wall625of the enclosure body624.

In this case, the window690is disposed in an aperture in a wall625of the enclosure body624(rather than the enclosure cover) that opposed the wall625on which the devices610are disposed. Mating threads684disposed on the outer surface of the lens691of the window690couple to mating threads627that form an aperture in the wall625of the enclosure body624, forming a flame path669between the enclosure body624and the window690. Also, the window690includes a lens691, a transition layer682, a sealing member, and a distal layer683. Also, in this example, there is no optical device (e.g., optical device475, optical device577) in the example illuminated viewing system680. Further, the sensor660, the switch670, the power supply640, and the light source assembly642are all disposed within the cavity607of the enclosure600. In other words, none of these components of the illuminated viewing system680are disposed within the lens691of the window690. The light644emitted by the light source assembly642is directed toward the VFD606and the circuit breaker629are mounted on the opposing side wall625of the enclosure body624.

Further, in this case, the sensor660, the switch670, the power supply640, and the light source assembly642are all clustered relatively close together. The sensor660of the example illuminated viewing system680ofFIG. 6is disposed on the distal surface of the distal layer683of the window690within view of the lens681. The power supply640, which in this case is coupled to the sensor660and the light source assembly642using one or more electrical conductors609, is disposed against the inner surface of a wall625of the enclosure body624, adjacent to where the window690is disposed. The switch670is integrated with the power supply640in this example. In addition, the light source assembly642is disposed on the distal surface of the distal layer683of the window690, outside of the view of the lens681.

Referring now toFIG. 7, the enclosure700ofFIG. 7is substantially the same as the enclosure400ofFIG. 4, the enclosure500ofFIG. 5, or the enclosure600ofFIG. 6, except as described below. For example, the enclosure700ofFIG. 7includes an enclosure body724coupled to an enclosure cover702and is located in an ambient environment711. A window790of an illuminated viewing system780is disposed in a wall703of the enclosure cover702. Specifically, mating threads784disposed on the outer surface of the lens791of the window790couple to mating threads727that form an aperture in the wall703of the enclosure cover702, forming a flame path769between the enclosure cover702and the window790. Also, the window790includes a lens791, a transition layer782, a sealing member765, and a distal layer783.

The devices710(in this example, a VFD706and a circuit breaker729) are mounted on a back wall725of the enclosure body724. In this case, there is no optical device (e.g., optical device475, optical device577) in the example illuminated viewing system780. Further, the sensor760ofFIG. 7is disposed partly in the wall703of the enclosure cover702and partially exposed to the ambient environment711. The power supply740(which has the switch770integrated therewithin) and the light source assembly742are coupled to each other and are disposed on the inner surface of the wall703adjacent to the window790. The light source assembly742, when illuminated, emits light744within the cavity707of the enclosure700toward the devices710disposed on the opposing back wall725of the enclosure body724.

The sensor760of the example illuminated viewing system780ofFIG. 7can be wirelessly coupled to the combination power supply740and switch770. For example, the sensor760can include a magnet that allows the sensor760to be magnetically coupled to the combination power supply740and switch770. In this way, if the enclosure700is located in a hazardous environment, the wireless coupling between the sensor760and the combination power supply740and switch770can eliminate another penetration through the wall703of the enclosure cover702, thereby eliminating a flame path (e.g., flame path769) that must be maintained.

Referring now toFIG. 8, the enclosure800ofFIG. 8is substantially the same as the enclosure400ofFIG. 4, the enclosure500ofFIG. 5, the enclosure600ofFIG. 6, or the enclosure700ofFIG. 7, except as described below. In this example, the enclosure cover is removed, exposing the contents (e.g., devices810such as a terminal block, a circuit breaker, a relay, a sensor) within the enclosure body824. As such, the coupling features820(in this case, apertures) disposed around and that traverse the enclosure engagement surface808are visible. The enclosure800is located in an ambient environment811.

In this case, there is no optical device (e.g., optical device475, optical device577) in the example illuminated viewing system880. Further, this example illuminated viewing system880includes two windows890. Window890-1is disposed in the right side wall825of the enclosure body824, and window890-2is disposed in the left side wall825of the enclosure body824.

There are also two sensors860in the example illuminated viewing system880ofFIG. 8. Sensor860-1is disposed within the lens891-1of window890-1, and sensor860-2is disposed within the lens891-2of window890-2. The power supply840and the switch870are combined into a single component and is disposed along the back wall825of the enclosure body824. The light source assembly842is disposed on the inner surface of the top wall825of the enclosure body824.

In some cases, these light source assemblies described herein can be “driverless”, meaning that they may not require a separate power source. In such a case, the power requirements of the light source assemblies would be low. For example, a light source assembly could be powered by a battery or other energy storage device. This would be possible because the duration of illumination of a light source assembly would be relatively short (e.g., for as long as a user needs to perform a visual inspection of the devices within the enclosure), often on the order of 5-10 seconds. The short duration of illumination allows for high power density due to the large thermal mass of the enclosure, as the enclosure is often made of thermally conductive material. In addition, the light emitted by the light source assemblies in example embodiments is sufficiently strong, despite being low profile, capable of sufficient lumens (e.g., 100-500) per square inch of mounting surface.

FIGS. 9-11show various light source assemblies in accordance with certain example embodiments. Specifically,FIG. 9shows light source assembly942,FIG. 10shows light source assembly1042, andFIG. 11shows light source assembly1142. Referring toFIGS. 1-11, the light source assembly942ofFIG. 9includes a circular circuit board943, a number of light sources945(e.g., LEDs) disposed around the top surface of the circuit board943, and a number of discrete components947(e.g., resistors, capacitors) disposed on the top surface toward the center of the circuit board943adjacent to the light sources945.

The light source assembly1042ofFIG. 10includes a pair of rectangular-shaped circuit boards1043(circuit board1043-1and circuit board1043-2) aligned next to each other and disposed on a mounting plate1049. Each circuit board1043includes a number of light sources1045(light sources1045-1for circuit board1043-1and light sources1045-2for circuit board1043-2) disposed on the top surface of the respective circuit board1043, and a number of discrete components1047(discrete components1047-1for circuit board1043-1and discrete components1047-2for circuit board1043-2) disposed on the top surface at the left end of the circuit board1043adjacent to the light sources1045.

The light source assembly1142ofFIG. 11includes a number of small square circuit boards1143disposed on a mounting plate1149, and a light source1145disposed on the top surface of most of the circuit boards1143. Some of the circuit boards1143have no light source1145, but are capable of receiving a light source1145. In some cases, there is only a single circuit board1143with a single light source1145mounted the mounting plate1149.

Example embodiments allow a user to visually inspect one or more devices within an enclosure without opening the enclosure. Example embodiments include at least one light source that directs light toward components (e.g., devices) located within the cavity of the enclosure, where the enclosure includes a window disposed in a wall or cover of the enclosure. The light source illuminates under certain conditions, such as the detection of a person near the window of the enclosure. Example embodiments can also be used in specific environments (e.g., hazardous environments) so that the enclosure maintains compliance with any applicable standards for that environment.