Adjustable Fan for a Microwave Appliance

The present subject matter relates generally to microwave appliances, and more particularly to fans in over-the-range microwave appliances.

Over-the-range microwave appliances are generally mounted above a cooktop of an oven range appliance. In addition to providing for heating of food and beverage items, certain over-the-range microwave appliances include a circulation system. When activated, the circulation system can draw fumes, smoke, grease, and/or steam away from the cooktop of the oven range appliance. Circulation systems generally include a fan for drawing a flow of air into the circulation system and a grease filter for trapping grease entering the circulation system.

Over-the-range microwave appliances generally have a radial blower fan that can be adjusted to recirculate or externally vent through an air vent. The installer of the microwave appliance can adjust the blower fan by removing certain parts to access and remove the radial blower fan, in order to reposition the fan. In other words, to switch venting directions after installation of the microwave appliance, the microwave appliance needs to be uninstalled and then reinstalled with the fan repositioned to change the venting direction. At times, installers may overlook ducting in the home and install the microwave appliance without properly orienting the blower fan to the functional position. This can lead to the failure of the magnetron and the cooking air not being vented in the desired direction for the consumer.

Accordingly, a microwave appliance with features for adjusting the circulation of the microwave appliance without uninstalling and reinstalling the fan would be useful.

Aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention.

In a first example embodiment, a microwave appliance is provided. The microwave appliance defines a vertical direction, a lateral direction, and a transverse direction. The vertical, lateral, and transverse directions are mutually perpendicular. The microwave appliance includes a casing that defines a cooking chamber configured for receipt of food items for cooking and the casing defines a circulation conduit. The circulation conduit has an inlet and an outlet. A door is mounted to the casing and configured for permitting selective access to the chamber of the casing. A fan assembly is positioned within the casing. The fan assembly includes a discharge housing that includes a plurality of discharge ports, and a fan housing mounted within the discharge housing. The fan housing is selectively rotatable within the discharge housing. The fan housing includes an outlet configured to align with a selected one of the plurality of discharge ports. The fan housing includes a toothed gear. The fan assembly further includes a fan wheel rotatably mounted within the fan housing. The fan wheel is configured to circulate air through the outlet of the fan housing and the selected one of the plurality of discharge ports. An access rod extends from a distal end at the toothed gear to a proximal end at a front of the casing in the transverse direction. The access rod includes a spiral thread at the distal end. The access rod is configured to rotate, thereby rotating the toothed gear and thereby the fan housing.

In a second example embodiment, a fan assembly is configured to be positioned within a casing of an appliance. The fan assembly includes a discharge housing that includes a plurality of discharge ports, and a fan housing mounted within the discharge housing. The fan housing is selectively rotatable within the discharge housing. The fan housing includes an outlet configured to align with a selected one of the plurality of discharge ports. The fan housing includes a toothed gear. The fan assembly further includes a fan wheel rotatably mounted within the fan housing. The fan wheel is configured to circulate air through the outlet of the fan housing and the selected one of the plurality of discharge ports. An access rod extends from a distal end at the toothed gear to a proximal end at a front of the casing. The access rod includes a spiral thread at the distal end. The access rod is configured to rotate, thereby rotating the toothed gear and thereby the fan housing.

These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention.

Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

provides a perspective view of a microwave applianceaccording to an example embodiment of the present subject matter mounted to an upper set of kitchen cabinetsabove an oven range appliance, e.g., along a vertical direction V. Microwave applianceshown inis commonly referred to as an over-the-range microwave. It should be understood that, in alternative example embodiments, the present subject matter may be used in any other suitable microwave appliance.

As discussed above, microwave applianceis mounted to upper set of kitchen cabinets. Upper set of kitchen cabinetsis positioned above a base set of kitchen cabinets, e.g., along the vertical direction V. Base set of kitchen cabinetsincludes countertopsand drawers. Microwave applianceis positioned above base set of kitchen cabinets, e.g., along the vertical direction V. Oven range applianceis received within base set of kitchen cabinetsbelow microwave appliance. In particular, a cooking surfaceof oven range applianceis positioned, e.g., directly, below microwave appliancealong the vertical direction V. Microwave appliancecan include features such as an air handler or fan assembly() that can draw cooking vapors and/or smoke away from cooking surfaceand out of the kitchen containing microwave and oven range appliancesand.

Microwave applianceis configured for receipt of food items for cooking. In particular, microwave applianceincludes a cabinet or casingand a doorthat permits selective access to an interior of microwave applianceand casing. Doorincludes a handlethat a user can pull to open door in order to insert food items into microwave appliance. Microwave appliancealso includes controlsthat permit a user to make selections for cooking of food items, e.g., a duration of a cooking cycle of microwave applianceand/or a power setting for the cooking cycle of microwave appliance.

As discussed above, oven range applianceincludes cooking surface. Cooking surfaceincludes heated portionsthat may be heated by heating elements (not shown), e.g., electrical resistive heating elements, gas burners, induction heating elements, and/or any other suitable heating element of combination of heating elements. Oven range appliancealso includes a doorthat permits access to a heated compartment (not shown) of oven range appliance, e.g., for cooking or baking of food items therein. A control panelof oven range appliancecan permit a user to make selections for cooking of food items, e.g., a duration of a cooking cycle of oven range applianceand/or a power setting for the cooking cycle of oven range appliance.

provides a side, section view of microwave applianceand oven range appliance. As may be seen in, casingextends between a top portionand a bottom portion, e.g., along the vertical direction V. Thus, top, and bottom portionsandof casingare spaced apart from each other, e.g., along the vertical direction V. In particular, casingmay include a front wall, a top wall, and a back wallas will be described further hereinbelow. Casingmay generally define a cooking chamberconfigured for receipt of food items for cooking. Doorpositioned adjacent to front wallof casingof microwave appliancepermits selective access to cooking chamberof casing. In particular, doorof microwave applianceis selectively adjustable between an open position (not shown) and a closed position (). In the closed position, doorof microwave appliancehinders access to cooking chamberof casing. Conversely, doorof microwave appliancepermits access to cooking chamberof casingin the open position. A user can pull on handleof doorof microwave appliancein order to shift doorfrom the closed position shown into the open position.

Casingalso defines a circulation passage or conduit. Circulation conduithas an inletand an outlet. Circulation conduitextends between inletand outlet. Inletof circulation conduitis positioned at or adjacent bottom portionof casing, e.g., such that inletof circulation conduitfaces cooking surfaceof oven range appliance. Conversely, outletof circulation conduitis positioned at or adjacent top portionof casing, e.g., such that outletof circulation assemblyfaces away from cooking surfaceof oven range appliance. Thus, inletand outletof circulation conduitare spaced apart from each other, e.g., along the vertical direction V.

Microwave appliancemay include a fan assembly, such as an axial fan or a radial fan. Fan assemblymay be positioned within or adjacent circulation conduit. Fan assemblymay draw or urge a flow of air (shown with arrows F) through circulation conduitwhen fan assemblyis in an activated state. Conversely, fan assemblymay not draw or urge flow of air F through circulation conduitwhen fan assemblyis in a deactivated state. When fan assemblyis in the activated state, flow of air F enters circulation conduitat, or through, inletof circulation conduit. In the present example embodiment, flow of air F is directed through circulation conduitto outlet, and flow of air F can exit circulation conduitat outletof circulation conduit. As described above, fan assemblyis described in a recirculation orientation where flow of air F is directed through circulation conduitto outlet, however, fan assemblymay be configurable to direct flow of air F in other desired directions. Fan assembly, and other possible orientations of fan assemblywill be described in further detail hereinbelow.

Microwave appliancemay also include an air filter. Air filtermay be mounted to casingsuch that flow of air F within circulation conduitpasses through air filterwhen fan assemblyis in the activated state. In the example embodiment shown in, air filteris positioned within circulation conduitat outletof circulation conduit. It should be understood that in alternative example embodiments, air filtermay be positioned at any other suitable location on microwave appliance.

As may be seen in, microwave applianceincludes a controller. Operation of microwave applianceis regulated by controller. Controlleris operatively coupled or in communication with various components of microwave appliance, including controls. In response to user manipulation of controls, controlleroperates the various components of microwave applianceto execute selected cycles and features.

Controllermay include a memory and microprocessor, such as a general or special purpose microprocessor operable to execute programming instructions or micro-control code associated with a cleaning cycle. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor. Alternatively, controllermay be constructed without using a microprocessor, e.g., using a combination of discrete analog and/or digital logic circuitry (such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software. Controlsand other components of microwave appliancemay be in communication with controllervia one or more signal lines or shared communication busses.

Microwave appliancealso includes a magnetron. Magnetronis configured for generating microwaves and directing such microwaves towards or into cooking chamberof casing. Magnetroncan be positioned at any suitable location within microwave appliance. For example, magnetronmay be mounted to casing, e.g., at or adjacent top portionof casing, such that magnetronis positioned at or adjacent cooking chamberof casing. Controllercan selectively activate magnetron, e.g., in order to heat food or beverage items in cooking chamber, based at least in part on an activation signal received from controls. Further, controllermay also be in operative communication with fan assembly. Thus, controllermay selectively adjust fan assemblybetween the activated and deactivated states in order to regulate the flow of air F through circulation conduit.

Illustrated inis example embodiment of fan assembly. As may be seen in, fan assemblymay include a discharge housing. In general, discharge housingmay extend between a top side, a bottom side, a first side wall, a second side wall, a front side, and a back side, e.g., discharge housingmay be generally rectangular in shape. As may be seen in, discharge housingmay be divided into two sections in the lateral direction L, e.g., discharge housingmay be two independent sections separated by a toothed gearof a fan housing, as will be described hereinbelow. In general, discharge housingmay be symmetrical across toothed gearin order to provide modularity of fan assembly. Discharge housingmay generally define a plurality of discharge ports, e.g., a first discharge port, a second discharge port, and a third discharge port. In example embodiments, the plurality of discharge ports,, andincludes three discharge ports, first discharge port, second discharge port, and third discharge port, facing in different directions. In general, the plurality of discharge ports,, andmay be oriented in any suitable direction. For example, first discharge portmay be defined in front sideof discharge housing(e.g., the first discharge portmay generally face forward along the transverse direction T), second discharge portmay be defined in top sideof discharge housing(e.g., the second discharge portmay generally face upward along the vertical direction V), and third discharge portmay be defined in back sideof discharge housing(e.g., the third discharge portmay generally face backward along the transverse direction T). As may be seen in, the plurality of discharge ports,, andmay each be defined as pairs of discharge ports, such as one port on each section of discharge housingforming pairs of discharge ports such that discharge housingis symmetrical across toothed gear.

As may be seen in, a fan housingmay be mounted within discharge housing, e.g., fan housingmay include two sections, one on each side of toothed gear, e.g., one in each respective section of discharge housing. In particular, turning to, discharge housingmay include an opening, e.g., a cylindrically shaped opening in each of first side walland second side wallof discharge housing. Fan housingmay include an outer surfaceand may be cylindrical, and concentric with openingof discharge housing, such that fan housingfits within openingin both of the transverse direction T and vertical direction V. In some example embodiments, fan housingmay be any other suitable shape, such as a cube, cuboid, prism, etc. Furthermore, fan housingmay be made from any suitably rigid or flexible material, such as using a suitable plastic material such as injection molding grade Polybutylene Terephthalate (PBT), Nylon 6, high impact polystyrene (HIPS), acrylonitrile butadiene styrene (ABS), or any other suitable blend of polymers. In other words, fan housingmay be laterally, in the lateral direction L, positioned within, and rotatable within, openingof the discharge housing. For example, in the present example embodiment, fan housingmay be selectively rotatable within discharge housing. In particular, fan housingmay include an outlet, in each respective section within discharge housing, configured to align with a selected one of the plurality of discharge ports,, and. For example, fan housingmay be rotatable between a first position (as seen in), wherein outletis aligned with first discharge portand flow of air F is directed through first discharge port, a second position (as seen in), wherein outletis aligned with second discharge portand flow of air F is directed through second discharge port, and a third position (as seen in), wherein outletis aligned with third discharge portand flow of air F is directed through third discharge port. Notably, fan housingmay be rotatable within discharge housingwhile the discharge housingand fan housingare installed within microwave appliance. In example scenarios when fan housingis flexible, fan housingmay compress during rotation and spring back to its original position in order to align with the desired discharge port.

Referring again to, in general, fan housingmay include a fan wheel, e.g., in each section of fan housing. In particular, fan wheelmay be rotatably mounted within fan housingsuch that fan wheelmay be configured to circulate air through outletof fan housingand the selected one of the plurality of discharge ports,, and. For example, fan wheelmay be mechanically coupled to a motor() generally configured to rotate fan wheelwithin fan housing. Turning again to, fan wheelmay be mounted within fan housingon a fan axis FA parallel to, and spaced apart from, a housing axis HA of the fan housing. As such, an inside gapof fan housingfrom fan wheelmay be non-uniform and progressively increasing towards outletof the fan housing. For example, as explained above, fan housingmay be selectively rotatable within discharge housingbetween the plurality of discharge ports,, and, and offsetting fan axis FA from housing axis HA may thereby keep inside gapof fan housingfrom fan wheelnon-uniform and progressively increasing towards outletof fan housingwith respect to the selected one of the plurality of discharge ports,, and.

As stated above, fan housingmay be rotatable between a first position where outletis aligned with first discharge port, a second position where outletis aligned with second discharge port, and a third position where outletis aligned with third discharge port. As may be seen in, fan housingis shown in the first position, with outletaligned with first discharge port. When in the first position, flow of air F may flow out of first discharge portof discharge housingin the transverse direction T, such that air may be recirculated through circulation conduit(e.g., as seen in). Turning to, fan housingis shown in the second position, with outletaligned with second discharge port. When in the second position, flow of air F may flow out of first discharge portof discharge housingin the vertical direction V, such that flow of air F may flow out an external duct (not shown) extending in the vertical direction V. Further, turning to, fan housingis shown in the third position, with outletaligned with third discharge port. When in the third position, flow of air F may flow out of third discharge portof discharge housingin the transverse direction T, opposite the direction of the first position, such that flow of air F may flow out back sideof discharge housingand out an external duct (not shown) in the transverse direction T.

Turning now to, in some example embodiments, fan assemblymay include a plurality of tabs, such as a first taband a second tab, extending in the lateral direction L from discharge housing, as well as a protrusionextending from outer surfaceof fan housing. First taband second tabmay be any suitable shape or size in order to engage protrusion, e.g., each of first taband second tabmay be cubic in shape, with a side-length of between one-tenth of a centimeter (0.1 cm) and one centimeter (1 cm), such as between one-quarter of a centimeter (0.25 cm) and three-quarters of a centimeter (0.75 cm), such as half of a centimeter (0.5 cm). Similarly, protrusionmay be any suitable shape or size in order to engage first taband second tab, respectively. For example, protrusionmay be rectangular with a base length of between one-tenth of a centimeter (0.1 cm) and one centimeter (1 cm), such as between one-quarter of a centimeter (0.25 cm) and three-quarters of a centimeter (0.75 cm), such as half of a centimeter (0.5 cm).

In general, the plurality of tabs, e.g., first taband second tab, may generally be positional guides for users rotating fan housing. In other words, protrusionfrom fan housingmay contact a respective tab of the plurality of tabs when fan housingis rotated within discharge housing. For example, when protrusionis rotated to engage with first tab, further rotation of fan housingmay be restricted, alerting the user that the fan housing is in the third position, as described above. In another example, when protrusionis rotated to engage with second tab, further rotation of fan housingmay be restricted, alerting the user that the fan housing is in the first position, as described above. Accordingly, as shown in, fan housingmay be in the second position when protrusionis approximately half-way between first taband second tab.

In some example embodiments, fan assemblymay include toothed gear. In general, fan housingmay be selectively rotatable within discharge housingwhile installed within microwave appliancevia rotating toothed gear. For example, toothed gearmay be a gear, or other suitable structure for rotating fan housingwithin discharge housingwhile the discharge housingand fan housingare installed within microwave appliance. Additionally or alternatively, fan assemblymay be configured to be used in other suitable appliances or structures such as heating, ventilation, and air conditioning systems (HVAC) or vent hood appliances.

Turning now to, illustrated is an access rod() and a guide() positioned within microwave appliance(). In general, access rodmay be a cylindrical rod extending between a distal endand a proximal end. In particular, distal endof access rodmay be positioned at toothed gearof fan housingand proximal endmay be positioned at front wallof casing, in the transverse direction T. Furthermore, access rodmay include an engagement portionat proximal endand a spiral threadat distal end. In some example embodiments, engagement portionmay extend slightly, e.g., by between one-tenth of a centimeter (0.1 cm) and one centimeter (1 cm), such as between one-quarter of a centimeter (0.25 cm) and three-quarters of a centimeter (0.75 cm), such as half of a centimeter (0.5 cm), from front wallof casing. For example, engagement portionmay include a knob or protrusion such that the user may access the knob from the front side of microwave applianceand may rotate fan housingusing the knob. In general, access rodmay be configured to rotate, such as by a user rotating engagement portion, e.g., engagement portionmay be rotated clockwise or counterclockwise by tools such as a screwdriver or a wrench, or in some example embodiments, by hand. For example, engagement portionmay include flat outer surfaces configured to engage a wrench or socket or may additionally or alternatively include perpendicular slots for engaging a screwdriver, such as a Phillips-head screwdriver. In particular, rotating engagement portionof access rodmay rotate spiral threadat distal end, whereby spiral threadmay engage and rotate toothed gear, and thereby rotate fan housing. As such, fan housingmay be selectively rotatable within discharge housingbetween the plurality of discharge ports,, andby rotating access rodat front wallof casingof microwave appliance. In general, other embodiments may include components for rotating fan housingin conjunction with and/or separate from access rod. For example, microwave appliancemay include a lever configured rotate fan housing, such as by spinning or pulling the lever. Furthermore, other example embodiments may include embodiments where access rodmay be a wire or pully mechanism, generally configured to rotate fan housingwhen engaged.

As stated above, a guidemay be positioned within microwave appliance. In general, guidemay hold access rodin place, such that spiral threadat distal endengages with toothed gear. In particular, guidemay be positioned along access rodbetween proximal endand distal end. In other words, guidemay define a channelconfigured to receive access rodbetween proximal endand distal end. Guidemay generally define a plurality of mounting holes. In particular, guidemay be secured to top wallof casingvia fasteners, such as screws, engaging the plurality of mounting holesthrough top wall. For example, it may be understood by one of skill in the art that the fasteners shown within the plurality of mounting holesinmay be inserted into the plurality of mounting holesof guidefrom outside of topof casing, e.g., such that the fasteners may extend through top wallinto guide. While top wallis not shown infor clarity of the other components, one of skill in the art would understand top wallmay generally extend between front walland back wallover top (in the vertical direction V) of guideand around second discharge portof fan assembly. Accordingly, access rodmay be securely held within guidesuch that engagement portionis positioned at front wall(e.g., accessible to a user) and spiral threadis positioned at toothed gear.

As may be seen from the above, a modular discharge casing in an over-the-range microwave appliance may include a fan housing. The discharge casing may allow the fan housing to rotate therein. Additionally, the discharge casing may be equipped with multiple openings, allowing the fan housing to be rotated and aligned with any of these openings. Advantageously, the fan housing may be rotatable within the discharge casing while the discharge casing and fan housing are installed within the microwave appliance via an access rod. Thus, installation and maintenance may be simplified and also flexibility may be provided for directing the airflow to specific locations or accommodating different configurations without removing the modular discharge casing from the microwave appliance, hence advantageously making the discharge casing of the over-the-range microwave appliance convenient for the users.

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.