WO2008034049A1

WO2008034049A1 - Centrifugal fan for a compact air purifier

Info

Publication number: WO2008034049A1
Application number: PCT/US2007/078477
Authority: WO
Inventors: Carl Triplett; Jeffrey Bankers; Kevin Hafer
Original assignee: The Dial Corporation
Priority date: 2006-09-15
Filing date: 2007-09-14
Publication date: 2008-03-20
Also published as: WO2008034052A1; WO2008034053A1; WO2008034055A1

Abstract

Exemplary embodiments of the present invention provide a rotatable compact air purifier comprising an airflow module. The airflow module comprises centrifugal fan. The centrifugal fan comprises a plurality of blades that are configured to extend substantially radially from a hub coupled to a motor. Exemplary fan blades do no require a squirrel cage or hoop-like structure to provide support and/or to connect the fan blades. The airflow module may further comprise an inlet and an outlet that may respectively comprise an inlet flow director and an outlet flow director.

Description

CENTRIFUGAL FAN FOR A COMPACT AIR PURIFIER

Field of Invention

This application generally relates to an air flow module for a compact air purifier, and more specifically to a centrifugal fan for a compact air purifier

Background of the Invention

In recent years there has been an increased emphasis on improving the quality of the air or "air health" of living spaces This has resulted m a corresponding mcrease in the popularity of consumer air freshening systems for use in pπvate homes It is often convenient to use an available receptacle (e g , a conventional household electπcal outlet) as a source of electπcal power for systems configured to achieve some type of environment- alteπng effect, such as air freshening or an- purification

In certain instances, these systems may be coupled to a receptacle to liberate floor or table space, however, conventional attachment methods for engagmg a device directly to an outlet may substantially cover and render useless an adjoining outlet Moreover, if there is little space adjacent to the outlet, many. air purification and air freshening devices may not fit in the space and, therefore, may not be used It would therefore be desirable to provide an air freshemng and/or air purification device that may be rotated about an axis to allow the device to fit into smaller spaces and not cover adjoining outlets

It may also be desirable to provide the user with an indication of when a filter or disposable device that contains an air freshening agent may need to be replaced Filters that remove air-born contaminants can become clogged with dirt, dust, hair, and other contaminants and need to be periodically replaced in order for the air freshemng or purification system to function properly Further, devices that contain a liquid, gel or other agents used to freshen the air may need to be replaced in order for maximum air freshemng to occur It would therefore be desirable to provide an air freshemng and/or purification device that mcludes an end-of-use indicator to remind the user to change the filter or air freshening agent

Summary of the Invention

In vaπous representative aspects, the present invention provides an air purification device that is compact or otherwise configured to integrate with its environment in a discreet manner. Exemplary features generally include a housing with a stationary base coupled to a rotatable body that substantially surrounds the stationary base and rotates around an axis of the stationary base, and a device disposed within the rotatable body configured to take air in, purify the air, and return purified air as output to the environment. In general, the device may include an air cleaning module and an airflow module. In accordance with a further embodiment, the air purification device may also include an optional vapor-dispensing module configured to add one or more fragrances to the purified air.

In an exemplary embodiment, the air purification device comprises an airflow module for moving air thorough the air purification device. The air flow module may comprise a fan, such as a centrifugal fan. The centrifugal fan comprises a hub coupled to a motor configured to drive the fan, and a plurality of fan blades coupled to the motor via the hub. In certain embodiments, the fan may comprise a backplate, wherein the fan blades abut the backplate and the hub is centrally located within the backplate. The air flow module may further comprise an inlet and an outlet. Exemplary fan blades extend substantially radially from a location proximate the hub, and each of the fan blades comprises a first edge, for example, an inlet edge, and a second edge opposite the first edge, for example, a backplate edge in an embodiment where the fan comprises a backplate. Each of the first edges of the fan blades may be configured so as not to be connected to the other first edges (e.g., via a hoop-like or squirrel cage configuration). Each of the second edges of the fan blades are configured to comprise a distance between the first edge and the second edge, wherein the distance may be constant, may increase, and/or may decrease across the fan blade.

In other embodiments, the air flow module may comprise an inlet flow director. An exemplary inlet flow director is configured to maintain a constant flow rate of air across the inlet of the air flow module.

Brief Description of the Drawings

The exemplary embodiments of the present invention will be described in conjunction with the appended drawing figures in which like numerals denote like elements and:

FIGS. Ia- Id illustrate various rotatable compact air purifiers in accordance with exemplary embodiments of the present invention; FIG. 2 illustrates a plug pattern and a receptacle pattern in accordance with exemplary embodiments of the present invention;

FIG. 3 illustrates receptacle patterns in accordance with exemplary embodiments of the present invention; FIG. 4 illustrates an air purifier in accordance with exemplary embodiments of the present invention;

FIG. 5 illustrates a block diagram of a body portion of a rotatable compact air purifier in accordance with exemplary embodiments of the present invention;

FIG. 6 illustrates an air cleaning module of a rotatable compact air purifier in accordance with exemplary embodiments of the present invention;

FIGS. 7a-7q illustrate various airflow modules and/or fans in accordance with exemplary embodiments of the present invention;

FIGS. 8a-8b illustrate various air intake panel and air cleaning module configurations in accordance with exemplary embodiments of the present invention; FIGS. 9a-9b illustrate various air output panel and vapor-dispensing module configurations in accordance with exemplary embodiments of the present invention;

FIG. 10 illustrates a base portion having stop locations in accordance with exemplary embodiments of the present invention;

FIG. 11 illustrates a rotatable compact air purifier in accordance with exemplary embodiments of the present invention;

FIG. 12 illustrates an exploded view of a rotatable compact air purifier in accordance with exemplary embodiments of the present invention; and

FIGS. 13a-13b illustrates rear perspectives of two rotatable compact air purifiers in accordance with exemplary embodiments of the present invention.

Detailed Description

The following descriptions are of exemplary embodiments of the invention only, and are not intended to limit the scope or applicability of the invention in any way. Rather, the following description is intended to provide convenient illustrations for implementing various embodiments of the invention. As will become apparent, various changes may be made without departing from the spirit and scope of the invention as set forth in the appended claims. For the sake of brevity, functional embodiments of the apparatus and systems (and components of the individual operating components of the systems) may not be described m detail herein Furthermore, the connecting lines shown in the various figures contained herein are intended to represent exemplary functional relationships and/or physical connections between the various elements It should be noted that many alternative or additional functional relationships or physical connections may be present in a practical system

Systems and methods m accordance with vaπous embodiments of the present invention generally provide a rotatable compact air purifier An air purifier, m vaπous embodiments, may mclude any device, component, or combination of components suitably configured to scrub, purify, filter, sanitize, add a fragrance, scent, or other vapor, or otherwise process mcoming air to produce cleaner air as an output An air purifier, in vaπous embodiments, may be configured to rotate about an axis, and/or may be configured to provide a "plug through" receptacle pattern when occupying a receptacle pattern on a surface

An exemplary compact air puπfier compπses a base portion and a body portion configured to rotate about an axis defined by the base portion In exemplary embodiments, the body portion defines an airflow path therethrough For example, an airflow module draws air into the body portion through an air intake panel and across an air cleaning module A vapor-dispensmg module then disperses a fragrance, anosmic agent, scent, or other vapor mto the air being pushed out the body portion by the airflow module through an an- output panel

Turning now to the figures, and with specific reference to FIGS Ia- Id, an exemplary rotatable compact air puπfier 100 m accordance with this invention compπses a substantially stationary base portion 102 and a body portion 104 configured to rotate about an axis 106 defined by stationary base portion 102 As shown in FIGS Ia- Id, body portion 104 in accordance with this invention may or may not surround, or substantially surround, base portion 102 An- puπfier, as used herem, includes any system for air fragrancing, air masking (e g , with anosmic agents) and/or air puπfying Base portion 102 is configured to be attached to a surface 108 While any surface, indoor or outdoor, is within the scope of this invention, exemplary surfaces include walls, ceilings, floors, mirrors, windows, cabinets and appliances Base portion 102 may be attached to surface 108 via adhesives, bolts, dowels, hooks, sleeves, brackets, clips, suction or other means known in the art or hereafter devised. The attachment may be permanent or temporary, and the attachment may include a coupling, thereby allowing base portion 102 and surface 108 to be extended away from each other or closer to each other. An exemplary coupling may be adjustable or fixed.

In some embodiments, as shown in FIG. 2, base portion 202 is attached to surface 208 using plug patterns and receptacle patterns. For example, in some embodiments base portion 202 comprises a plug pattern 210 configured to interface with a receptacle pattern 212 on surface 208. In some embodiments, base portion 202 comprises more than one plug pattern 210. While any plug pattern operative to provide power to compact air purifier 100 is contemplated by this invention, exemplary plug patterns include telephone plugs (e.g., RJl 1), internet plugs (e.g., 8P8C), electrical plugs (e.g., 110-volt AC, 120-volt AC, 220-volt AC, 240-volt AC, polar, non-polar, 2 prong, 3 prong, duplex, quadplex, power strip, GFI), cable plugs (e.g., coaxial), and other plugs (e.g., USB, IEEE 1394, DVI, VGA, S-Video, 6- volt DC cigarette lighter, 12-volt DC cigarette lighter). Exemplary receptacle patterns 212 are shown in FIG. 3. In some embodiments, receptacle pattern 212 provides power to the compact air purifier. In other embodiments, the compact air purifier is powered by one or more batteries.

As shown in FIG. 4, in some embodiments, body portion 404 is configured to have a less conspicuous profile. For example, the horizontal cross-sectional profile ratio (thickness divided by the length) may asymptotically approach 0 at the edges 414 of body portion 404 and about 0.50 - 0.70 at the longitudinal center 416 of body portion 404. Therefore, body portion 404 is close to surface 408 at edges 414 of body portion 404 giving the perception of a less conspicuous air purifier. In some embodiments, the small size and shape at the edges, top, and/or bottom of body portion 404 allow access to a second receptacle pattern on surface 408 or allow the air purifier to fit into smaller spaces.

While any material is suitable for use in the body portion, exemplary materials include ceramic, cermet, composite, glass, rubber, plastic, silicone, and metal. Such exemplary materials may be opaque, transparent, or semi-transparent. As shown in FIG. 5, body portion 504 comprises one or more of an air cleaning module 520, an airflow module 530, an air intake panel 540, an air output panel 550, a receptacle pattern 560, and a vapor-dispensing module 570 configured to add one or more fragrances or anosmic agents to the air from the airflow module and/or the air cleaning module. In one exemplary embodiment, body portion 504 defines an airflow path therethrough. For example, airflow module 530 draws air into body portion 504 through air intake panel 540 and across air cleaning module 520. Vapor-dispensing module 570 then disperses a fragrance, anosmic agent, scent, or other vapor into the air being pushed out body portion 504 by airflow module 530 through air output panel 550.

An air cleaning module in accordance with this invention is any device suited for removing contaminants from the air within any physical or fictitious boundary. Exemplary contaminants include microbes (e.g., bacterium, viruses, and the like), allergens (e.g., pollen, dander, lint, dust, smog, mold, smoke, and the like), and/or malodors (e.g., chemical odors, microorganism odors, and the like) ranging in size from about 0.01 to about 100 microns in diameter or more. In exemplary embodiments, contaminants as small as 3 microns in diameter are filtered out at 60% or greater efficiency and the Clean Air Delivery Rate (CADR), a function of airflow and efficiency, is greater than about 6.

Air cleaning module 520 may comprise, for example, one or more of a liquid or solid filter, such as an activated carbon filter, charcoal filter, particle filter, and electrostatic filter.

In accordance with a representative embodiment of the invention, the filter may be a fiber filter such as, for example, a high efficiency particulate air (HEPA) filter. In other embodiments, the filter may be a FILTRETE® filter (available from 3M Corporation of St.

Paul, Minnesota). In yet another representative embodiment of the invention, the filter may be a microbial filter configured to filter airborne bacterium and/or viruses.

Pore size of an exemplary filter is in the range of about 5 to 100 cells/inch. Carbon content of an exemplary filter is in the range of about 0.01 to 1.0 g/sq. in. Filter thickness of an exemplary filter is in the range of about 0.05 to 0.5 inch.

In another exemplary embodiment, air cleaning module 520 comprises one or more chemical absorbents to purify air. Examples of chemical absorbents include, but are not limited to, carbon, activated charcoal, baking soda, and/or the like. In yet another exemplary embodiment, air cleaning module 520 incorporates ultraviolet, ozonation, and/or ionization technologies to purify air.

In addition, more than one air cleaning module may be used. Air cleaning module 520 may comprise multiple layers, each having different properties and may either be flexible or rigid, planar or non-planar. In some embodiments, air cleaning module 520 is an activated, layered and non-woven carbon filter. In general, any technique, process, device, and/or component, now known or otherwise hereafter described in the art, for removing contaminants from the air is within the scope of this invention.

In some embodiments, as shown in FIG. 6, air cleaning module 620 is configured to conform to an airflow module 630 such that the distance d between a substantial portion of a surface 622 of air cleaning module 620 and the inlet 632 of airflow module 630 is uniform. For example, air cleaning module 620 may be configured to be non-planar. In this manner, the distance d the air travels from air cleaning module 620 to inlet 632 of airflow module 630 is uniform, regardless of whether the air enters at the center 624 or periphery 626 of air cleaning module 620. This configuration maximizes the efficiency of airflow module 630 as well as air cleaning module 620.

In some embodiments, as shown in FIG. 6, air cleaning module 620 is non-planar to increase the effective surface area thereof. For example, air cleaning module 620 may be configured to have waves 628. In some embodiments, air cleaning module 620 is disposable. Airflow module 530, in accordance with various embodiments of the invention, may be any device configured to push, pull, draw or otherwise facilitate the movement of air. An exemplary airflow module comprises an impeller, blower and/or fan and may comprise any fan configuration including axial, centrifugal, cross flow and hybrids thereof. Generally, axial fans move air entering parallel to the shaft in a direction parallel to the shaft about which the blades rotate; centrifugal fans move air entering parallel to the shaft in a direction perpendicular to the shaft; and cross flow fans move air entering perpendicular to the shaft in another direction perpendicular to the shaft. According to further embodiments, airflow module 530 may be any device now known or later contemplated that is configured to move air. In accordance with exemplary embodiments of the invention, and with reference to

FIGS. 7a-7q, airflow module 530 comprises a centrifugal fan 731 that comprises a backplate 738 with a hub 733 that is centrally located in backplate 738. A motor is coupled to and/or is configured to interface with hub 733 to facilitate the rotation of backplate 738. Backplate 738 comprises a plurality of fan blades 734 that extend radially from a location proximate hub 733 to a location proximate the circumference of backplate 738. An exemplary centrifugal fan may further comprise an inlet configured to allow air to enter the fan and an outlet configured to allow air to exit the fan. In connection with the inlet and the outlet, the centrifugal fan may comprise an inlet flow director and/or an outlet flow director. An exemplary backplate 738 comprises a circular configuration with hub 733 located at the center of the circle and fan blades 734 extending radially from proximate hub 733 to proximate the circumference of the circle. Exemplary fan blades 734 may or may not contact hub 733. In other embodiments, backplate 738 may not be circular, but may be rectangular or any other shape configured to facilitate the movement of air through centrifugal fan 731. In still other embodiments, fan 731 may not comprise backplate 738, but may comprise another structure for coupling the motor to hub 733 and fan blades 734.

In accordance with another embodiment of the invention, fan blades 734 may comprise a backplate edge 735 that is located adjacent to backplate 738, an inlet edge 736 opposite backplate edge 735 and located proximate the fan inlet, an outlet edge 737 disposed between backplate edge 735 and inlet edge 736 and configured to move past the fan outlet, and an air direction profile that is defined by the manner in which fan blades 734 are curved or not curved. In an embodiment where fan 731 does not comprise backplate 738, backplate edge 735 is configured to comprise an edge of fan blades 734 that is opposite, not adjacent to, and/or not contacting inlet edge 736. Fan blade configurations according to embodiments of the present invention may be any configuration capable of moving air between a fan inlet and a fan outlet. Exemplary fan blades are illustrated in FIGS. 7a-7q.

With continued reference to FIGS. 7a-7q, further exemplary embodiments comprise fan blades 734 where inlet edge 736 is not parallel to backplate edge 735. Such embodiments comprise inlet edges 736 that taper, slope, and or increase or decrease in height as measured from hub 733 to the circumference of backplate 738, and from backplate edge 735 to inlet edge 736. Other inlet edges 736 may comprise a portion that is parallel to backplate edge 735 and a portion that is not parallel to backplate edge 735 (see, e.g., FIG. 7c). Still other inlet edges 736 may comprise other portions or segments that have different and/or the same slopes (see, e.g., FIGS. 7c-7i).

Exemplary fan blades 734 may have various air direction profiles. For example, fan blades 734 may be configured to be forward curved, backward curved, radial, and/or flat. A forward curved configuration describes a fan blade 734 that is curved in the direction of the rotation of fan 731. More specifically, if the rotation is clockwise, the radial end of fan blade 734 - the end near the outside of backplate 738 - is located further along the circumference of backplate 738, in a clockwise direction, than a fan blade with no curvature would be located. For example, if air flow module 530 illustrated in FIG. 7f rotates clockwise, fan blades 734 are forward curved. On the other hand, for a clockwise-rotating fan 731, a backward curved fan blade 734 has a radial end located further, in a counterclockwise direction, than a fan blade 734 with no curvature. Other embodiments comprise air direction profiles that are combinations and/or hybrids of the above, or any configuration operable to move air through airflow module 530. Fan blade configurations may comprise a centrifugal fan (see, e.g., FIG. 7a), radial blades (see, e.g., FIGS. 7b, 7f), bowl-shaped blades (see, e.g., FIGS. 7c, 7g), star-shaped blades (see, e.g., FIGS. 7d, 7e, 7h, 7i), vertical blades no chamfer tip (see, e.g., FIG. 7j), angled blades with chamfer tip (see, e.g., FIGS. 7k, 71), vertical blades with chamfer tip (see, e.g., FIG. 7m), vacuum style blades (see, e.g., FIG. 7o), vacuum style blades with forward- back twist (see, e.g., FIG. 7p), vacuum style blades with trailing tip (see, e.g., FIG. 7q). Other configurations are contemplated, for example, traditional paddle style blades, high and low blades, vacuum style blades with forward twist, vacuum style blades with no twist, vacuum style blades with back twist, and vacuum style blades with trailing tip and draft.

Centrifugal fan 731 may comprise any suitable number of fan blades 734. For example, centrifugal fan 731 may comprise 6, 8, 12, 16, 17, 18, 19, 24, 30 or 36 fan blades 734. In some embodiments, fan blades 734 are designed to minimize the disturbance in the center area and create airflow outward to the edge.

Fan blades 734, according to further embodiments, may or may not extend continuously from hub 733 to the edge of backplate 738. For example, in some embodiments, fan blades 734 may be configured to form a "hamster wheel" configuration, where fan blades 734 are relatively short compared to the distance from hub 733 to the edge of backplate 738. In other embodiments, fan blades 734 are configured to extend completely from hub 733 to the edge of backplate 738, and in still other embodiments, fan blades 734 extend only a portion of the distance between hub 733 and the edge of backplate 738. In further embodiments, fan blades 734 may or may not require a hoop-like structure at the edge of the fan (see, for example, the hoop-like structure depicted in FIG. 7a) and/or a hamster wheel configuration to connect and/or provide support to fan blades 734, and in yet other embodiments, fan 731 may not comprise backplate 738. Where fan 731 does not comprise backplate 738 is not required, the motor is coupled to fan blades 734 via hub 733. Table 1 shows speed, air flow and noise data for exemplary fan blade configurations.

Table 1

AIR

FILTER SPEED(RPM) FLOW(CFM) NOISE(dB)

An exemplary air flow module 530 may also be configured to comprise an inlet that draws in air from the surrounding environment and an outlet that expels filtered air back to the surrounding environment. Where air flow module 530 comprises a centrifugal fan (such as fan 731), the inlet is operative to draw in air from the surrounding environment in an axial direction relative to the centrifugal fan, and the outlet is configured to expel air in a radial direction relative to the centrifugal fan. Other embodiments of the invention may also comprise an inlet flow director and an outlet flow director positioned proximate the respective inlet and outlet of air flow module 530. Such mlet and outlet flow directors are configured to aid in directing the inlet an" in the axial direction relative to the centrifugal fan and the outlet air in the radial direction relative to the centrifugal fan.

Further embodiments of the invention provide a fan that is configured to provide a desired air flow profile across the inlet and/or outlet of the air flow module. The inlet and outlet flow directors may be configured to provide such a desired air flow profile. For example, with momentary reference to FIG. 12, an exemplary inlet flow director 1240 is configured to provide a certain air flow distribution and/or air flow direction at the inlet of air flow module 530. Similarly, exemplary outlet flow director 1250 is configured to provide a certain air flow distribution and/or air flow direction at the outlet of air flow module 530. According to other embodiments of the invention, other geometries and structures may provide desired air flow distributions at the inlet and outlet and remain within the scope of the present invention. In certain embodiments of the invention, the flow directors may be part of air intake panel 540, in other embodiments, they may be disposed between air intake panel 540 and air flow module 530, and in other embodiments, they may be part of air flow module 530. With reference back to FIG. 6, and with reference again to FIGS. 7a-7q, an air purifier according to exemplary embodiments of the present invention may utilize centrifugal fan 731 and a conforming filter assembly to provide more efficient air purification. An exemplary fan and conforming filter assembly comprises centrifugal fan 731 , a filter, such as air cleaning module 620, and a separation distance d between the filter and an inlet of centrifugal fan 731, such as inlet 632 of airflow module 630. The exemplary assembly may also comprise an airflow director operative to increase the efficiency of the air purification. As discussed above, embodiments of centrifugal fan 731 comprise fan blades 734 that have inlet edges 736 located proximate the fan inlet and/or inlet 632 of air flow module 630. Also, as previously discussed, inlet edges 736 may be tapered, partially or completely, or may comprise other shapes that facilitate air flow through air flow module 630. Inlet edges 736 of fan blades 734, when taken together, form an inlet profile, for example, as shown on FIG. 6 for inlet 632. Such an inlet profile may be configured to be concave, convex, dome-shaped, triangular-shaped, flat, and/or any other configuration or combination of configurations that facilitate air flow through air flow module 630.

As shown in FIG. 6, a filter, such as air cleaning module 620, may be configured to be a distance d away from every point of the inlet profile of centrifugal fan 731. Such a configuration aids in efficient air purification, because the filter will wear at an even rate across the entire surface of the filter. This even wear may result from an even flow distribution across the inlet of the fan which is due at least in part to the configuration of fan blades 734 and the corresponding inlet profile. In other embodiments of the invention, however, the flow distribution across the inlet of air flow module 530 may not be constant. In fact, the flow rate at different points of the inlet may be greater or less than the flow rate at other points of the inlet. In order to account for this variation in inlet flow rates, the filter may be located closer to the inlet over certain portions of the inlet to allow the filter to be consumed at an even rate across the entire surface of the filter. For example, where the inlet has an inlet high flow rate portion and an inlet low flow rate portion (e.g., where the filter would be subjected to higher and lower flow rates of air if each point on the filter were equidistant from each point on the inlet), the distance d between the filter and the inlet high flow rate portion may be greater than the distance d between the filter and the inlet low flow rate portion. In another embodiment, the separation distance d may be configured according to high and low flow rate regions at the inlet of fan 731. Such a change in separation distances is configured to compensate for differences in inlet flow rates in order to allow the filter to be more efficiently consumed.

In yet another embodiment of the invention, where the inlet flow rate is variable across inlet 632 of air flow module 630, the fan and conforming filter assembly may further comprise an air flow director. The air flow director may be disposed between the filter and inlet 632, the air flow director may be located outside of the filter and/or outside of the compact air purifier, or the flow director may be located in any position and/or configuration that facilitates the efficient and even consumption of filter 620. The air flow director may comprise a funnel shape, a baffle shape, and/or any shape configured to direct the flow of air between filter 620 and inlet 632. For example, where an outside portion of filter 620 is subjected to a lower air flow rate than the center of filter 620, the air flow director might reduce the air flow rate through the center of filter 620 and might increase the air flow rate around the outside portion of filter 620.

In another embodiment, inlet flow director 1240 may also comprise the air flow director; for example, the slits in inlet flow director may be variably sized in order to change the flow rate through different portions of inlet flow director 1240. In another embodiment, inlet flow director 1240 may be curved around inlet 632 so that the distance that the air travels from filter 620 to inlet 632 is the same distance regardless if the air comes in from the center of filter 620 or around the periphery. In still other embodiments, the air flow director may comprise any device or configuration that facilitates the equalization of air flow over the surface of filter 620 in order to cause filter 620 to be consumed at an equal rate over the entire surface of filter 620.

In accordance with another exemplary embodiment of the invention, and with reference again to FIG. 5, airflow module 530 comprises ionization technology configured to create an active air flow through the air purifier via an electric field. In yet another embodiment, airflow module 530 comprises a pump suitably configured to cause the air to flow through the air purifier.

Air intake panel 540 in accordance with this invention is any device suited for allowing air to enter the air purifier. Similarly, air output panel 550 in accordance with this invention is any device suited for allowing air to exit the air purifier. Air intake panel 540 and air output panel 550 may comprise one or more vents, slats and/or other aperture(s). Panels 540 and 550 may further comprise a mesh or screen. Panels 540 and 550 may also prevent users from damaging the inner components of the air purifier or injuring themselves by touching electrical or moving components within the air purifier housing. In some embodiments, air intake panel 540 is configured to support various inner components of the air purifier, for example, air cleaning module 520. Similarly, air output panel 550 may be configured to support various inner components of the air purifier, for example, vapor- dispensing module 570.

While any material is suitable for use in panels 540 and 550, exemplary materials include ceramic, cermet, composite, glass, rubber, plastic, silicone, and metal, and may be opaque, transparent, or semi-transparent. Alternatively, or in addition, panel 540 and/or 550 may add decorative effects to the air purifier, or be otherwise configured to make the air purifier less conspicuous. For example, the air purifier may be configured to resemble a decorative item, such as a flower, or a common household item, such as a plug or switch pattern.

As alluded to above, air intake panel 540 may be configured to support or conceal air cleaning module 520. In some embodiments, as shown in FIG. 8a, air intake panel 840 is removably attached to body portion 804. This configuration provides access to air cleaning module 820 for example, for cleaning or replacement. In other embodiments, as shown in FIG. 8b, air intake panel 840 is attached to air cleaning module 820 by glue or another type of adhesive or mechanical fastening mechanism 822, and together are removably attached to body portion 804 for cleaning or replacement. Accordingly, the user of the air purifier would replace air cleaning module 820 by simply replacing the entire removable air intake panel 840 that air cleaning module 820 is attached to. In yet other embodiments, air intake panel 840 and air cleaning module 820 are the same module.

In some embodiments, air output panel 550 may be removably attached to body portion 504. In some embodiments, air output panel 550 is configured to direct air in a desired direction. For example, it may be configured to direct air away from the surface upon which the air purifier is positioned. Alternatively, it may be configured to direct air toward the surface upon which the air purifier is positioned so as to use the surface to assist in dispersing the air.

Receptacle pattern 560 in accordance with this invention may be any receptacle pattern, including those that interface with the plug patterns listed above. As a non-limiting example, receptacle pattern 560 is advantageous in embodiments occupying a receptacle pattern on the surface that provides power to the compact air purifier as is acts as a "plug through" receptacle pattern, thus making available an otherwise occupied power source.

Vapor-dispensing module 570 in accordance with this invention may be any device suited for storing and/or dispersing a fragrance, anosmic agent, scent, or other vapor into the air. In accordance with an exemplary embodiment, vapor-dispensing module 570 comprises a reservoir or other device, such as an emanator pad, to store and/or disperse a fragrance, anosmic agent, scent, or other vapor, in liquid, gel or solid form. In some embodiments, vapor-dispensing module 570 comprises a heating element. Air output panel 550 may be configured to support or conceal vapor-dispensing module 570. In some embodiments, as shown in FIG. 9a, air output panel 950 is removably attached to body portion 904. This configuration provides access to vapor-dispensing module 970 for example, for cleaning or replacement. In other embodiments, as shown in FIG. 9b, air output panel 950 is attached to vapor-dispensing module 970 by glue or another type of adhesive or mechanical fastening mechanism 972, and together are removably attached to body portion 904 for cleaning or replacement. Accordingly, the user of the air purifier would replace vapor-dispensing module 970 by simply replacing the entire removable air output panel 950 that vapor-dispensing module 970 is attached to. In yet other embodiments, air output panel 950 and vapor-dispensing module 970 are the same module.

The amount of fragrance, anosmic agent, scent, or other vapor dispensed by vapor- dispensing module 570 in exemplary embodiments may be regulated utilizing a controller. The controller may comprise a control lever in communication with vapor-dispensing module 570 and may be any device, component, or combination of components, whether now known or otherwise hereafter described in the art, that are capable of controlling the rate at which additives, fragrances, anosmic agents, scents, or other vapors are dispersed into the air.

In operation of one embodiment of the air purifier, airflow module 530 is configured to move air through, around, or across vapor-dispensing module 570 such that the air is fragranced before being purified by the cleaning module 520. In this embodiment, air cleaning module 520 may be configured in a manner that will not substantially filter out any fragrance added to the air. In operation of another embodiment of the air purifier, airflow module 530 is configured to move purified air through, around, or across vapor-dispensing module 570 such that the air is fragranced after being purified by air cleaning module 520. In operation of yet another embodiment of the air purifier, it may comprise a plurality of vapor-dispensing modules 570.

In accordance with various embodiments, and with momentary reference back to FIGS. la-Id, body portion 104 is configured to rotate about an axis 106 defined by stationary base portion 102. Body portion 104 being rotatable allows access to a second receptacle pattern on surface 108 or allows air purifier 100 to fit into smaller spaces. With momentary reference to FIG. 2, body portion 104 being rotatable may be especially advantageous since plug pattern 210 may be polar. Polar plug patterns are those having a prong larger than, or otherwise different from, another, thereby necessitating a particular orientation for plug pattern 210 to interface properly with receptacle pattern 212.

In some embodiments, as shown in FIG. Ic, stationary base portion 102 extends through body portion 104. In some embodiments, stationary base portion 102 may comprise any component of air purifier 100 so as to maintain the uprightness thereof while body portion 104 rotates about axis 106 defined by stationary base portion 102. For example, stationary base portion 102 may comprise an end-of-use indicator that provides the user with a visual indication that air cleaning module 520 or vapor-dispensing module 570 needs to be replaced. The indicator may comprise words and/or numbers visible and readable by the user because base portion 102 extends through body portion 104 and does not rotate with body portion 104. Notwithstanding this non-limiting example, it is not necessary that stationary base portion 102 extend through body portion 104.

In some embodiments, a first stop location on stationary base portion 102 interacts with a second stop location on rotatable body portion 104 to prevent it from rotating substantially freely about axis of rotation 106. In an exemplary embodiment, body portion 104 rotates -90 degrees counter-clockwise and +180 degrees clockwise and can be used at any degree of rotation within that range. "Soft stops," or temporary stops, are provided at 0 and +90 degrees clockwise. "Solid stops," or permanent stops, are provided at -90 and +180 degrees clockwise. In an exemplary embodiment, and as shown in FIG. 10, base portion 1002 comprises

"soft stop" apertures 1080 at 0, 90, 180 and 270 degrees from the top center that engage a stop member 1090 on body portion 1004 located at 180 degrees from the top center. Base portion 1002 further comprises "solid stop" tabs 1095 at 0 and 270 degrees from the top center that engage stop member 1090. In this exemplary embodiment, a spring may be used to connect body portion 1004 to base portion 1002. When stop member 1090 meets apertures 1080, the force the spring places on body portion 1004 forces stop member 1090 to enter apertures 1080. The user can "unlock" stop member 1090 from apertures 1080 by simply pulling body portion 1004 away from base portion 1002 and rotating it so that stop member 1090 is no longer aligned with apertures 1080. In an alternative embodiment, the permanent stops may be eliminated in favor of additional temporary stops. In another alternative embodiment, the temporary stops may be eliminated in favor of additional permanent stops. Any number or placement of temporary stops or permanent stops may be used within the scope of the present invention. In one representative aspect of an exemplary embodiment of the invention, rotatable body portion 104 may be configured to rotate three-hundred and sixty degrees around receptacle pattern 212. Accordingly, exemplary air purifiers may be suitably configured for proper function when attached, for example, "upside-down," "side ways," and/or "right side- up" (or any intermediate rotational conformation) with respect to orientation of receptacle pattern 212.

Finally, an air purifier in accordance with this invention may further comprise one or more of a light (e.g., a night-light), an end-of-use indicator (e.g., LED/timer circuit, electromechanical device, or color change time strip.), and an audible effect device (e.g., to play soothing sounds like beaches, waterfalls, wildlife, raindrops).

An end-of-use indicator provides the user with a visual and/or audible indication that air cleaning module 520 needs to be replaced. In accordance with this exemplary embodiment, the end-of-use indicator may be activated after a set period of time passes. Specifically, the end-of-use indicator may comprise a timer that is activated when power from an outlet (or other power source) is delivered to the air purifier. The timer counts down a pre-programmed time period and activates the end-of-use indicator after that time period has elapsed. For example, if the end-of-use indicator is set for thirty days, the end-of- use indicator is activated thirty days after the air purifier is connected to an outlet. Various visual and/or audible devices may be used as end-of-use indicators. Examples include, but are not limited to, LEDs, other light sources, audible alarms, and color changing time strips. Alternatively, or additionally, an end-of-use indicator provides the user with an indication that vapor-dispensing module 570 needs to be replaced in a manner similar to that described above.

One or more of any element of body portion 504, including air cleaning module 520, airflow module 530, and vapor-dispensing module 570, may be partially or completely, activated and/or deactivated, manually or automatically using any device now known or later contemplated. For example, compact air purifier 100 may comprise one or more of a manual switch, an air contaminant sensor, a motion sensor, a light sensor, and a timing device. For example, airflow module 530 may be activated when motion or light is sensed. In embodiments having one or more sensors, compact air purifier 100 may comprise a plurality of air cleaning modules 520, airflow modules 530, and/or vapor-dispensing modules 570, each configured to respond to a different stimulus. For example, purifier 100 may comprise different air cleaning modules 520 configured to respond to light and dark. Alternatively, or additionally, purifier 100 may comprise different vapor-dispensing modules 570 configured to respond to carbon monoxide and ethanols. Each module may function alone or in combination in response to a detected stimulus.

Exemplary embodiments are shown in FIGS. 11-13. FIG. 11 shows an air purifier 1100 having a plug pattern 1110, an air intake panel 1140, an air output panel 1150, and a receptacle pattern 1160. FIG. 12 shows an air purifier 1200 having an air cleaning module 1220, an airflow module 1230, an air intake panel 1240, an air output panel 1250, a receptacle pattern 1260, and a vapor-dispensing module 1270. FIGS. 13a and 13b depict an air purifier 1300 and how, in certain embodiments, body portion 1304 may or may not surround, or substantially surround, base portion 1302.

It should be understood that the foregoing description is of exemplary embodiments of the invention only, and that the invention is not limited to the specific forms shown. Various modifications may be made in the design and arrangement of the elements set forth herein without departing from the scope of the invention.

Claims

CLAIMSWhat is claimed is:

1. A centrifugal fan for use in a compact air purifier, comprising: a motor; a backplate coupled to a hub centrally located in the backplate, wherein the hub is coupled to the motor; a plurality of fan blades extending radially from a location proximate the hub, wherein the plurality of fan blades abuts the backplate, each of the fan blades comprising: a backplate edge adjacent the backplate; an inlet edge opposite the backplate edge, wherein the inlet edges of the plurality of fan blades are not coupled to each other; an outlet edge disposed between the backplate edge and the inlet edge; and an air direction profile; an inlet; and an outlet.

2. A centrifugal fan according to claim 1 , further comprising an inlet flow director and an outlet flow director.

3. A centrifugal fan according to claim 1, wherein the air direction profile comprises a forward curved direction profile.

4. A centrifugal fan according to claim 1, wherein the air direction profile comprises a backward curved direction profile.

5. A centrifugal fan according to claim 1, wherein the air direction profile comprises a radial direction profile.

6. A centrifugal fan according to claim 2, wherein the inlet flow director comprises an axial flow director.

7. A centrifugal fan according to claim 2, wherein the outlet flow director comprises a radial flow director.

8. A centrifugal fan according to claim 1, wherein the fan does not comprise a hoop-like structure for connecting the plurality of blades to each other.

9. A centrifugal fan according to claim 1 , wherein the fan does not comprise a squirrel cage configuration for connecting the plurality of blades to each other.

10. A centrifugal fan according to claim 1, wherein the inlet edge comprises a tapered inlet edge.

11. A centrifugal fan according to claim 1 , wherein each of the plurality of blades further comprises a distance between the backplate edge and the inlet edge.

12. A centrifugal fan according to claim 11, wherein the distance between the backplate edge and the inlet edge increases radially from the hub toward the circumference of the backplate.

13. A centrifugal fan according to claim 11, wherein the distance between the backplate edge and the inlet edge decreases radially from the hub toward the circumference of the backplate.

14. A centrifugal fan according to claim 2, wherein the inlet flow director is configured to maintain a substantially uniform flow rate across the inlet.

15. An airflow module for use in an air purifier, comprising: a hub coupled to a motor; a plurality of fan blades coupled to the motor via the hub and extending substantially radially from proximate the hub, wherein each of the plurality of fan blades comprises: (a) a first edge, wherein the first edges of the plurality of fan blades are not coupled to each other; and (b) a second edge opposite and not adjacent to the first edge, wherein a distance between the first edge and the second edge is not constant; and an inlet flow director.

16. An airflow module according to claim 15, wherein the second edge comprises a backplate edge, and wherein the first edge comprises an inlet edge.

17. An airflow module according to claim 15, wherein the distance between the first edge and the second edge increases in a direction extending radially from the hub.

18. An airflow module according to claim 15, wherein the distance between the first edge and the second edge decreases in a direction extending radially from the hub.