VACUUM CLEANER

Abstract

A surface cleaning apparatus has first and second cleaning stages, a pre-motor filter and a suction motor. The second cleaning stage comprises at least one cyclone. The components are laterally and vertically spaced with respect to other components.

Claims

1.-16.

17. A surface cleaning apparatus comprising: (a) an air flow path extending from a dirty fluid inlet to a clean air outlet; (b) a first cleaning stage comprising an air treatment chamber positioned in the air flow path, the air treatment chamber having an upper end and an opposed lower end, wherein an air treatment chamber axis extends between the upper and lower ends, wherein an air treatment chamber air inlet and an air treatment chamber air outlet are provided in the upper end; (c) a second cleaning stage positioned in the air flow path downstream from the first cleaning stage wherein the second cleaning stage comprises at least one cyclone; (d) a pre-motor filter positioned in the air flow path downstream from the second cleaning stage, the pre-motor filter having an upstream surface and a downstream surface; and (e) a suction motor positioned in the air flow path downstream from the pre-motor filter, wherein the suction motor has a motor axis of rotation, wherein the second cleaning stage is laterally spaced from the air treatment chamber, and wherein the pre-motor filter is also laterally spaced from the air treatment chamber, and wherein, when the surface cleaning apparatus is positioned on a horizontal surface with the upper end of the air treatment chamber above the lower end of the air treatment chamber, an upper end of the at least one cyclone is positioned at a higher elevation than the air treatment chamber.

18. The surface cleaning apparatus of claim 17 wherein the second cleaning stage overlies the pre-motor filter.

19. The surface cleaning apparatus of claim 17 wherein an air outlet of the second cleaning stage faces the pre-motor filter.

20. The surface cleaning apparatus of claim 19 wherein the pre-motor filter is removably positionable in a pre-motor filter housing and the air outlet of the second cleaning stage faces an air inlet end of a pre-motor filter housing.

21. The surface cleaning apparatus of claim 17 wherein the pre-motor filter is removably positionable in a pre-motor filter housing and, when the surface cleaning apparatus is positioned on a horizontal surface with the upper end of the air treatment chamber above the lower end of the air treatment chamber, a lower surface of the second cleaning stage faces an air inlet end of a pre-motor filter housing.

22. The surface cleaning apparatus of claim 17 wherein the suction motor is laterally spaced from the air treatment chamber.

23. The surface cleaning apparatus of claim 17 wherein, when the surface cleaning apparatus is positioned on a horizontal surface with the upper end of the air treatment chamber above the lower end of the air treatment chamber, a lower end of the pre-motor filter is positioned above an air inlet of the suction motor.

24. The surface cleaning apparatus of claim 17 wherein a first plane that is transverse to the air treatment chamber axis extends through the air treatment chamber and the pre-motor filter and a second plane that is transverse to the air treatment chamber axis extends through the air treatment chamber and the suction motor.

25. A surface cleaning apparatus comprising: (a) an air flow path extending from a dirty fluid inlet to a clean air outlet; (b) a first cleaning stage comprising an air treatment chamber positioned in the air flow path, the air treatment chamber having an upper end and an opposed lower end, wherein an air treatment chamber axis extends between the upper and lower ends, wherein an air treatment chamber air inlet and an air treatment chamber air outlet are provided in the upper end; (c) a second cleaning stage positioned in the air flow path downstream from the first cleaning stage wherein the second cleaning stage comprises at least one cyclone; (d) a pre-motor filter positioned in the air flow path downstream from the second cleaning stage, the pre-motor filter having an upstream surface and a downstream surface; and (e) a suction motor positioned in the air flow path downstream from the pre-motor filter, wherein the suction motor has a motor axis of rotation, wherein the second cleaning stage is laterally spaced from the air treatment chamber, and wherein the pre-motor filter is also laterally spaced from the air treatment chamber, and wherein the suction motor is also laterally spaced from the air treatment chamber. wherein, when the surface cleaning apparatus is positioned on a horizontal surface with the upper end of the air treatment chamber above the lower end of the air treatment chamber, a lower end of the pre-motor filter is positioned above an air inlet of the suction motor.

26. The surface cleaning apparatus of claim 25 wherein the air treatment chamber axis and the motor axis of rotation are parallel.

27. The surface cleaning apparatus of claim 26 wherein air travels through the air treatment chamber air outlet is a flow direction and the flow direction is parallel to the air treatment chamber axis.

28. The surface cleaning apparatus of claim 25 wherein, when the surface cleaning apparatus is positioned on a horizontal surface with the upper end of the air treatment chamber above the lower end of the air treatment chamber, an inlet of the suction motor is positioned at a lower end of the suction motor.

29. The surface cleaning apparatus of claim 25 wherein a plane that is transverse to the air treatment chamber axis extends through the air treatment chamber and the pre-motor filter

30. The surface cleaning apparatus of claim 25 wherein a plane that is transverse to the air treatment chamber axis extends through the air treatment chamber and the suction motor.

31. The surface cleaning apparatus of claim 25 wherein the flow path comprises a passage that extends from the first cleaning stage to the second cleaning stage wherein, when the surface cleaning apparatus is positioned on a horizontal surface with the upper end of the air treatment chamber above the lower end of the air treatment chamber, the passage is positioned at an elevation above the upper end of the air treatment member and an upper end of the at least one cyclone.

32. A surface cleaning apparatus comprising: (a) an air flow path extending from a dirty fluid inlet to a clean air outlet; (b) a first cleaning stage comprising an air treatment chamber positioned in the air flow path, the air treatment chamber having an upper end and an opposed lower end, wherein an air treatment chamber axis extends between the upper and lower ends, wherein an air treatment chamber air inlet and an air treatment chamber air outlet are provided in the upper end; (c) a second cleaning stage positioned in the air flow path downstream from the first cleaning stage wherein the second cleaning stage comprises at least one cyclone; (d) a pre-motor filter positioned in the air flow path downstream from the second cleaning stage, the pre-motor filter having an upstream surface and a downstream surface; and (e) a suction motor positioned in the air flow path downstream from the pre-motor filter, wherein the suction motor has a motor axis of rotation, wherein the second cleaning stage is laterally spaced from the air treatment chamber, and wherein the pre-motor filter is also laterally spaced from the air treatment chamber, and wherein, when the surface cleaning apparatus is positioned on a horizontal surface with the upper end of the air treatment chamber above the lower end of the air treatment chamber, the second cleaning stage overlies the pre-motor filter.

33. The surface cleaning apparatus of claim 32 wherein the suction motor is laterally spaced from the air treatment chamber.

34. The surface cleaning apparatus of claim 32 wherein the air treatment chamber axis and the motor axis of rotation are parallel.

35. The surface cleaning apparatus of claim 32 wherein, when the surface cleaning apparatus is positioned on a horizontal surface with the upper end of the air treatment chamber above the lower end of the air treatment chamber, a lower end of the pre-motor filter is positioned above an air inlet of the suction motor.

36. The surface cleaning apparatus of claim 32 wherein the flow path comprises a passage that extends from the first cleaning stage to the second cleaning stage wherein, when the surface cleaning apparatus is positioned on a horizontal surface with the upper end of the air treatment chamber above the lower end of the air treatment chamber, the passage is positioned at an elevation above the upper end of the air treatment member and an upper end of the at least one cyclone.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] These and other advantages of the present invention will be more fully and particularly understood in connection with the following description of the preferred embodiments of the invention in which:

[0027] FIG. 1A is a perspective illustration of an embodiment of a surface cleaning apparatus of the present invention;

[0028] FIG. 1B is a perspective illustration of another embodiment of a surface cleaning apparatus of the present invention;

[0029] FIG. 1C is a perspective illustration of another embodiment of a surface cleaning apparatus of the present invention;

[0030] FIG. 1D is a perspective illustration of another embodiment of a surface cleaning apparatus of the present invention;

[0031] FIG. 2A is a cross-sectional view of the embodiment of FIG. 1A, taken along line 2A-2A;

[0032] FIG. 2B is a cross sectional view of the embodiment of FIG. 1B, taken along line 2B-2B;

[0033] FIG. 2C is a cross sectional view of the embodiment of FIG. 1C, taken along line 2C-2C;

[0034] FIG. 2D is an exploded view of the embodiment of FIG. 1D;

[0035] FIGS. 3A to 5A are top views of various embodiments of a dirt chamber of the present invention;

[0036] FIGS. 3B to 5B are side views of the embodiments of FIGS. 3A to 5A;

[0037] FIGS. 3C-5C are perspective views of the embodiments of FIGS. 3A to 5A;

[0038] FIG. 6 is a perspective view of the surface cleaning apparatus of FIG. 1A, showing a panel in an opened position; and,

[0039] FIG. 7 is a perspective view of the surface cleaning apparatus of FIG. 2A, showing a panel in an opened position.

DETAILED DESCRIPTION OF THE INVENTION

[0040] Embodiments of a surface cleaning apparatus 110 of the present invention are shown in FIGS. 1A-1D. As shown in FIGS. 1A and 1C, the surface cleaning apparatus 110 may be a hand vacuum cleaner, which may be converted to a shoulder strap vacuum cleaner by the addition of a shoulder strap (not shown). Alternatively, as shown in FIGS. 1B and 1D, the surface cleaning apparatus 110 may be a shop-vac or wet/dry type vacuum cleaner. In other embodiments, the surface cleaning apparatus 110 may be another type of surface cleaning apparatus, for example an upright vacuum cleaner, a canister type vacuum cleaner, a stick vacuum cleaner, a back pack vacuum cleaner, a carpet extractor or the like.

[0041] The surface cleaning apparatus 110 comprises a dirty fluid inlet 112, a clean fluid outlet 114, and a fluid flow path extending therebetween. The dirty fluid inlet 112 may also be referred to as inlet conduit 112. Inlet conduit 112 has an inlet conduit axis 113 that extends horizontally when the surface cleaning apparatus 110 is positioned on a horizontal surface. Referring to FIGS. 1A and 2A, as exemplified, the surface cleaning apparatus 110 has a forward portion 190. At least one cyclonic cleaning stage 116 is provided in the fluid flow path. As shown, the at least one cyclonic cleaning stage 116 is positioned in the forward portion 190. The forward portion 190 has a vertical rear exterior wall 192 when the surface cleaning apparatus 110 is positioned on a horizontal surface. A volume 193, through which air flows after passing through the cyclone 120, is provided. As exemplified in FIG. 1A, the inlet conduit axis 113 extends through the vertical rear exterior wall 192. The inlet conduit axis 113 also extends through the volume 193. As exemplified in FIG. 1A, when positioned on the horizontal surface, the surface cleaning apparatus 110 has a rear portion 194 that is positioned rearward of the cyclonic cleaning stage 116. The rear portion 194 has an upper wall 196 which is an exterior surface of the surface cleaning apparatus 110. As exemplified, a finger gap 200 is positioned above the upper wall 196 of the rear portion 194 and longitudinally between a handle 174 and the vertical rear exterior wall 192. A longitudinal axis 111 extends between the front and rear ends of the surface cleaning apparatus 110. As exemplified in FIG. 2A, the longitudinal axis 111 extends through the handle 174, the finger gap 200, the rear wall 192, the volume 193 and the cyclonic cleaning stage 116. A fluid flow motor 118 is positioned in the fluid flow path for drawing a fluid (e.g. air or water) from the dirty fluid inlet 112 to the clean fluid outlet 114. The surface cleaning apparatus may draw in water and/or air that may have entrained therein dirt through inlet 112 and discharge air through outlet 114. The water and/or dirt will accumulate in dirt chamber 144.

[0042] Referring to FIGS. 2A to 2D, dirty fluid entering dirty fluid inlet 112 is directed to cyclonic cleaning stage 116. As is known in the art, a hose or wand having a distal inlet that may be mounted on a surface cleaning head may be attached to inlet 112. In the embodiments shown, cyclonic cleaning stage 116 comprises a single cyclone chamber 120 extending longitudinally along a first longitudinal axis 122. In other embodiments, cyclonic cleaning stage 116 may comprise a plurality of cyclones. Cyclone chamber 120 comprises a clean air outlet 124, and a dirt and/or water outlet 126. A dirt chamber 144, as will be described further hereinbelow, is positioned below dirt outlet 126. It will be appreciated that other cleaning or treatment stages may be provided upstream of the cyclone inlet.

[0043] In some embodiments, air exiting cyclone chamber 120 may be directed past motor 118, and out of clean fluid outlet 114. Alternatively, air exiting cyclone chamber 120 may be directed to one or more additional cleaning stages, such as another component, for example housing a filter prior to flowing to motor 118. The second cleaning 128 stage comprises a plurality of second cyclones 130 in parallel.

[0044] The second cleaning stage 128 has, in the examples illustrated, a generally cylindrical configuration with a second longitudinal axis 132. In the embodiments of FIGS. 2A, 2B, and 2D, the second axis 132 is parallel to, and laterally offset from, first axis 122. In the embodiment of FIG. 2C, the second axis 132 is parallel to and aligned with first axis 122. In the embodiments shown in FIGS. 2A and 2B, each of the second cyclones 130 in the assembly receives air from the clean air outlet 124 of the first cyclone, and discharges air through outlets 134 into a manifold 136. Air is evacuated from the manifold 136 through a conduit 138 disposed centrally of the assembly. From the conduit 138 the air is drawn towards the motor 118, and expelled from the apparatus 110 through the exhaust 114. In the embodiment of FIG. 2C, each of the second cyclones 130 receives air from the clean air outlet 124 of the first cyclone via a conduit 137, and discharges air via outlets 134 into a manifold 139. From manifold 139, the air is drawn through a filter 141, and past motor 118. In the embodiment of FIG. 2D, each of the second cyclones 130 receives air from the clean air outlet 124 of the first cyclone via a conduits 127, and discharges air via outlets 134 into a motor housing 142. Alternately or in addition, in some embodiments the additional cleaning stage 128 may include a filter element, such as a pre-motor foam membrane, disposed in the fluid stream between the cleaning stage 128 and the motor 118.

[0045] In the embodiments shown in FIGS. 2A-2C, motor 118 is disposed laterally adjacent the additional cleaning stage 128, in a motor housing 142. In the embodiment of FIG. 2D, motor 118 is disposed laterally adjacent the first cleaning stage above the additional cleaning stage, namely filters 141 and second cyclonic cleaning stage 128. In the embodiment of FIG. 2A, motor 118 extends transverse to first longitudinal axis 122 and the axis of rotation 119 of the motor 118 extends through the cyclonic cleaning stage 116. In the embodiment of FIGS. 2B-2D, motor 118 extends parallel to first longitudinal axis 122. The motor 118 is, in the examples illustrated, offset from the second cleaning stage 128, having a portion that abuts or is adjacent at least a portion of the dirt chamber. It will also be appreciated that motor housing may be adjacent both the first and second housings and, thereby defining a generally triangular configuration in top plan view. Motor 118 may alternately be positioned at any other location known in the surface cleaning arts, such as above or below the cyclonic cleaning stage. As exemplified in FIGS. 1A and 2A, the motor housing 142 may extend rearwardly of the vertical rear exterior wall 192.

[0046] As previously mentioned, cyclone chamber 120 is in fluid communication with a dirt chamber 144, which is positioned below the dirt outlet 126. Dirt chamber 144 serves to collect dirt that is removed, e.g., from the air passing through cyclone chamber 120 or water drawn in through inlet 112. Dirt chamber 144 may be of any configuration known in the art provided the dirt chamber inlet 150 is off centre. As exemplified, dirt chamber 144 comprises an upper portion 146, which is proximate cyclone chamber 120, and a lower portion 148. Dirt chamber 144 is bounded by at least one wall. In the embodiments shown, dirt chamber 144 is bounded by a top wall 152 a bottom wall 154, and at least one sidewall 156.

[0047] Dirt chamber 144 further comprises a dirt chamber inlet 150, which is preferably defined in upper portion 146, and more preferably defined in top wall 152. Dirt chamber inlet 150 is in fluid communication with dirt outlet 126 of cyclone chamber 120. In some embodiments, as shown, dirt chamber inlet 150 and dirt outlet 126 may coincide. In other embodiments, dirt chamber inlet 150 and dirt outlet 126 may be separate, and may have a channel or passage providing fluid communication therebetween (not shown).

[0048] Dirt chamber inlet 150 may be of a variety of shapes and sizes. In the preferred embodiment, dirt chamber inlet 150 has a circular outer perimeter 162. In further embodiments, wherein surface cleaning apparatus 110 comprises a divider plate, as will be described further hereinbelow, dirt chamber inlet 150 may be substantially annular.

[0049] Dirt chamber 144 may be of a variety of shapes and sizes. For example, in the embodiment of FIGS. 1A, 2A, and 5A-5C, dirt chamber 144 comprises two substantially rounded lobes having curved sidewalls 156. In the embodiment of FIGS. 1B, 2B, 1C and 2C, dirt chamber 144 comprises two lobes which comprise substantially straight sidewalls 156. In the embodiment of FIGS. 1D, 2D, and 3A-3C, dirt chamber 144 comprises a single rectangular chamber. In the embodiment of FIGS. 4A-4C, dirt chamber 144 comprises a single trapezoidal chamber.

[0050] In some embodiments shown, dirt chamber 144 comprises at least two sidewalls which meet at an angle. For example, in the embodiment of FIGS. 2B-2D, sidewalls 156a and 156b meet at a corner 157. Such embodiments may be advantageous because cyclonic action in the dirt chamber may be minimized or reduced by providing the dirt chamber with sidewalls, which meet at an angle. Accordingly, dirt in the dirt chamber may be prevented from being re-entrained the circulating air. In other embodiments, dirt chamber 144 may be of another shape. For example dirt chamber 144 may be cylindrical.

[0051] In the embodiments shown, dirt chamber 144 extends laterally beyond the cyclone chamber 120. That is, if cyclonic cleaning stage 116 has a maximum cross sectional area in a plane transverse to axis 122 (e.g. parallel to bottom wall 154), and dirt chamber 144 has a maximum cross sectional area in a plane transverse to axis 122 (e.g. parallel to bottom wall 154), the maximum cross sectional area of dirt chamber 144 is greater than the maximum cross sectional area of cyclonic cleaning stage 116. In some particular embodiments, the maximum cross sectional area of dirt chamber 144 is at least 25% larger, more preferably at least 50% larger and most preferably at least 75% larger than the maximum cross sectional area of cyclonic cleaning stage 116. Such embodiments may be advantageous because the overall volume of the dirt chamber may be increased without increasing the footprint of surface cleaning apparatus 110. In the embodiment of FIGS. 1A, 1C and 1D, dirt chamber 128 extends laterally such that a portion thereof is positioned beneath second cleaning stage 128. In the embodiment of FIG. 2A, dirt chamber 128 extends laterally such that a portion thereof is positioned beneath second cleaning stage 128, and motor 118.

[0052] It will be appreciated that in an alternate embodiment, dirt chamber 144 may have a cross sectional area in a plane transverse to axis 122 that is essentially the same as the cross sectional area of the cyclone 116 in a plane transverse to axis 122. This may be achieved by placing inlet 150 below inlet 126 but at adjacent sidewall 156. Thus the inlet 150 is off centre and dirt chamber 144 may be underneath only a portion of cyclone 116.

[0053] Referring to FIGS. 3A-3C, in some embodiments, dirt chamber 128 comprises a central axis 158 extending between upper portion 146, and lower portion 148. When surface cleaning apparatus 110 is positioned such that axis 122 extends vertically, central axis 158 may extend vertically between top wall 152 and bottom wall 154. Central axis 158 is positioned such that it extends through a centroid 160 of top wall 152. As used herein, the centroid of top wall 152 is defined as the point located centrally in the area A defined by dirt chamber 144 when viewed from above. For example, in the embodiment of FIGS. 3A-3C dirt chamber 144 is rectangular. When viewed from above, dirt chamber 130 has a Length L.sub.1 and a width W.sub.1, and centroid 160 is positioned at a point corresponding to ½ L.sub.1 and ½ W.sub.1. In another example, as shown in FIGS. 4A-4C, dirt chamber is substantially trapezoidal when viewed from the front. Accordingly, top wall 152 of dirt chamber 144 has a length L.sub.2, bottom wall 154 of dirt chamber 144 has a length L.sub.3, and dirt chamber 144 has a width W.sub.2. When viewed from above, area A is defined by L.sub.3 and W.sub.2. Therefore, in this embodiment, centroid 160 is positioned at a point corresponding to ½ L.sub.3 and ½ W.sub.2. In another example, as shown in FIGS. 5A-5C, dirt chamber has two elongate and rounded lobes. When viewed from above, dirt chamber 144 has an overall width W.sub.3, and an overall length L.sub.4. The centroid 160 is positioned at a point corresponding to % W.sub.3 and ½ L.sub.4.

[0054] Dirt chamber inlet 150 is off centre with respect to dirt chamber 144. That is, dirt chamber inlet 150 is spaced from central axis. In further embodiments, central axis 158 is spaced from longitudinal axis 122. Such embodiments may allow for the volume of dirt chamber 144 to be increased, without substantially increasing the footprint of surface cleaning apparatus 110.

[0055] Referring to FIGS. 3A-5C, dirt chamber inlet 150 may be spaced from central axis 158 by a distance X, which is defined as the shortest distance between a perimeter 162 of dirt inlet 150, and central axis 158. Distance X may vary depending on a variety of factors. Dirt chamber inlet 150 may be spaced from the central axis by a distance of at least 10% of the maximum length, L.sub.max. In a preferred embodiment, dirt chamber inlet 150 is spaced from central axis 158 by a distance of at least 15% of L.sub.max. In a more preferred embodiment, dirt chamber inlet 150 is spaced from central axis 158 by a distance of at least 25% of L.sub.max.

[0056] In some particular embodiments, as shown in FIGS. 5A-5C, the upper portion 146 of dirt chamber 144 has a perimeter 164, and dirt chamber inlet 150 is adjacent the perimeter.

[0057] Referring to FIGS. 6 and 7, the dirt chamber 144 preferably has an openable panel 166 to facilitate emptying debris collected therein. In the embodiment of FIG. 6, panel 166 comprises bottom wall 15, which is movable between open and closed positions. The bottom wall is preferably pivotally mounted to at least one sidewall 156. In the embodiment of FIG. 7, panel 166 comprises top wall 152 of dirt chamber 132. In this embodiment, when panel 166 is opened, cyclonic cleaning stage 116, motor 118, and second cleaning stage 128 pivot together with panel 166. In other embodiments, dirt collection chamber 144 may be emptyable by any means known in the vacuum cleaner art. For example, dirt collection chamber 144 may be removably mounted to the surface cleaning apparatus or otherwise openable.

[0058] The apparatus 110 may also include a divider plate 168 positioned adjacent the dirt outlet 126 of the first cyclone chamber 120. In the example illustrated in FIGS. 2A-2C, the divider plate 168 is positioned within the dirt chamber 144, adjacent to but spaced below the dirt outlet 126. In other embodiments, divider palate 168 may be positioned within dirt outlet 126. In such an embodiment, dirt chamber inlet 150 may be defined between top wall 152 and divider plate 168, and may be substantially annular. The divider plate 168 may generally comprises a disc 170 that, when positioned below the dirt outlet 126, has a diameter slightly greater than the diameter of the dirt outlet 126, and disposed in facing relation to the dirt outlet 126. The disc 170 is, in the example illustrated, supported by a pedestal 172. In the embodiment of FIGS. 2A and 2C, pedestal 172 extends upwardly from bottom wall 154 of the dirt chamber 144. In the embodiment of FIG. 2B pedestal 172 extends downwardly from top wall 152 of dirt chamber 144. Alternately, plate 168 may be mounted to a sidewall 156 of the dirt collection chamber 144.

[0059] In the embodiment of FIGS. 1A and 1C, the surface cleaning apparatus may be carried by a strap (not shown) or by using handle 174. In the embodiments of FIGS. 1B and 1D, the surface cleaning apparatus comprises one or more wheels 176, glides, or the like, for moving surface cleaning apparatus 110 along a surface.

[0060] In some embodiments, dirt chamber 144 preferably forms a portion of a casing member 177 for the apparatus 110 that is of a unitary, integral construction. For example, casing member 177 may comprise dirt chamber 144, the outer wall of cyclone chamber 120, a housing for the second cleaning stage 128, motor housing 142, and handle 174.

[0061] In some embodiments, dirt chamber 144 may comprise one or more liner bags 180, for example as shown in FIG. 2B, for lining dirt chamber 144 and aiding in emptying dirt chamber 144.

[0062] It will be appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments or separate aspects, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment or aspect, may also be provided separately or in any suitable sub-combination.

[0063] Although the invention has been described in conjunction with specific embodiments thereof, if is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention.