FILTER ASSEMBLY FOR A SURFACE CLEANING APPARATUS
A surface cleaning apparatus comprises a cyclone, a suction motor positioned downstream from the cyclone and a filter assembly downstream of the cyclone and upstream of the suction motor. The filter assembly comprises a longitudinally extending first filter media configured as a hollow body, a longitudinally extending secondary filter positioned interior the longitudinally extending first filter media, the longitudinally extending secondary filter configured as a hollow body and an inner longitudinally extending downstream air flow passage positioned transversely inwardly from the inner downstream surface of the longitudinally extending secondary filter. A longitudinally extending filter axis is generally parallel to a motor axis and intersects the suction motor. The secondary filter filters finer particulate matter than the longitudinally extending first filter media.
This application claims benefit of priority under 35 USC 120 as a continuation of co-pending U.S. patent application Ser. No. 13/416,155, filed on Mar. 9, 2012, now allowed, entitled FILTER ASSEMBLY FOR A SURFACE CLEANING APPARATUS, the specification of which is incorporated herein by reference in its entirety.
FIELDThis invention relates to a surface cleaning apparatus. In one particular embodiment, the surface cleaning apparatus is a cyclonic cleaning apparatus, such as a cyclonic surface cleaning apparatus and may be an upright vacuum cleaner. The surface cleaning apparatus is provided with an elongate filter compartment, which is preferably upstream of the suction motor.
INTRODUCTIONPrevious different constructions for a surface cleaning apparatus, such as a vacuum cleaner, are known in the art. Currently, vacuum cleaners, which utilize cyclonic cleaning stages, are known. Such devices may use one or two cyclonic cleaning stages. Typically, a pre-motor foam filter and a post-motor filter, such as a HEPA filter, may be provided. The pre-motor filter may be shaped as a disc so as to be positioned in the air flow passage from the cyclonic cleaning stage or stages to the suction motor. Accordingly, the pre-motor filter is relatively thin compared to its diameter in the direction of air flow through the passage. The pre-motor filter is designed to prevent hair and dirt which may exit the cyclonic cleaning stage from reaching the suction motor where it may cause damage to the suction motor. The post-motor HEPA filter is designed to filter carbon dust and other fine particulate matter which is in the air stream that has travelled past by the suction motor.
The carpet cleaning efficiency of a vacuum cleaner depends upon the velocity of the air flow at the dirty air inlet in the floor or the surface cleaning head. The greater the velocity, the greater the amount of particulate matter that may be entrained in the air flow entering the vacuum cleaner, and, in addition, the heavier the dirt particles that may be entrained in the air flow entering the vacuum cleaner. As the pre-motor filter becomes clogged, the back pressure through the vacuum cleaner will increase, thereby reducing the velocity of the air flow at the dirty air inlet. Accordingly, the pre-motor filter should, on occasion, be cleaned or replaced. Typically, consumers may not clean or replace this filter. Accordingly, over time, the performance of a vacuum cleaner will decrease.
In accordance with one broad aspect of this disclosure, a surface cleaning apparatus is provided which provides a filter downstream of a cyclone, and, preferably, upstream of the suction motor, which has an enhanced surface area. The surface area of the pre-motor filter is enhanced by configuring the pre-motor filter to extend longitudinally (e.g. the filter is an elongate filter member). For example, the face of the filter that has the greatest length may extend in a direction of air flow upstream of downstream of the filter (e.g., it may be generally parallel to the suction motor axis or the cyclone axis). Such a design may require the treated air exiting a cyclone to travel laterally through the filter. The longitudinally extending sides of the pre-motor filter are utilized to define the upstream surface of the pre-motor filter. This is in contrast with a typical design wherein the face of a filter having the greatest surface area is position facing the direction of air flow in the vacuum cleaner.
An advantage of this design is that a pre-motor filter having a substantially larger upstream surface may be provided. Accordingly, even if a consumer does not replace or clean the pre-motor filter, the cleaning efficiency of a vacuum cleaner may be maintained over a longer operating period.
In accordance with another aspect of this invention, the elongate filter member may be positioned aligned with (e.g. above or below) a cyclone. Accordingly, even though the air may travel axially from a cyclone outlet to the pre-motor filter, the upstream surface area of the pre-motor filter may still be enhanced. Further, this may be achieved without increasing the footprint of a vacuum cleaner. Accordingly, a vacuum cleaner, when viewed from above, may still be constructed that has a relatively small cross-section area (i.e. footprint).
In accordance with one broad aspect of this disclosure, there is provide a surface cleaning apparatus comprising:
an air flow passage extending from a dirty air inlet to a clean air outlet;
a cyclone positioned in the air flow passage and having a cyclone air inlet,
a cyclone air outlet and having a cyclone axis;
a suction motor positioned in the air flow passage and having a motor axis; and,
a filter assembly downstream of the cyclone air outlet and upstream of the suction motor, the filter assembly comprising a longitudinally extending filter axis that is generally parallel to the cyclone axis, spaced apart longitudinally extending upstream and downstream air flow passages and a longitudinally extending filter media therebetween.
In accordance with another broad aspect of this disclosure, there is provide a surface cleaning apparatus comprising:
an air flow passage extending from a dirty air inlet to a clean air outlet;
a cyclone positioned in the air flow passage and having a cyclone air inlet,
a cyclone air outlet and having a cyclone axis;
a suction motor positioned in the air flow passage and having a motor axis; and,
a filter assembly downstream of the cyclone air outlet and upstream of the suction motor, the filter assembly comprising a longitudinally extending filter axis, spaced apart longitudinally extending upstream and downstream air flow passages and a longitudinally extending filter member therebetween wherein at least a portion of one of the upstream and downstream air flow passages is positioned interior the filter media.
Any of the embodiments described herein may have one or more of the following features.
The longitudinally extending filter axis may be generally parallel to the motor axis.
The filter assembly may have a downstream end having a dirt collection recess.
The filter media may comprise a hollow body having at least one longitudinally extending peripheral wall.
The filter media may be annular.
The filter assembly may have an upstream end and a downstream end and the filter assembly further may comprise a longitudinally extending filter support wall having a central portion with a plurality of openings and a solid portion adjacent the downstream end.
The filter assembly may comprise a spaced apart outer wall facing the filter support wall, and the filter media is positioned adjacent the filter support wall and may overlie the central portion and at least part of the downstream solid portion.
The filter media may be positioned on an outer side of the filter support wall, the longitudinally extending upstream air flow passage may be positioned between the outer wall and the filter media and the longitudinally extending downstream air flow passage maybe positioned on an inner side of the filter support wall.
The filter media may be annular and the longitudinally extending downstream air flow passage may be positioned inside the filter media.
The longitudinally extending upstream airflow passage may have a dirt collection recess at the downstream end.
The filter media may be positioned on an inner side of the filter support wall, the longitudinally extending downstream air flow passage may be positioned between the outer wall and the filter media and the longitudinally extending upstream air flow passage may be positioned on an inner side of the filter support wall.
The filter media may be annular and the longitudinally extending upstream airflow passage may be positioned inside the filter media.
The longitudinally extending upstream airflow passage may have a dirt collection recess at the downstream end.
The longitudinally extending downstream air flow passage may have an end open adjacent the upstream end and the filter media may overlie the open end.
The longitudinally extending filter support wall may comprise a solid portion adjacent the upstream end and the filter media also may overlie at least part of the upstream solid portion.
The longitudinally extending downstream air flow passage may have an end open adjacent the upstream end and the filter media may overlie the open end.
The filter media may comprise a foam filter.
The filter media may comprise a longitudinally extending foam filter and a downstream longitudinally extending felt filter.
The filter media may be compressed between the upstream and downstream ends.
The filter media may be compressed against the filter support wall.
The filter member may comprise a hollow body.
The filter member may comprise an annular body.
The filter assembly may have an upstream end and a downstream end and the filter assembly further may comprise a longitudinally extending filter support wall having a plurality of openings and the filter member is positioned adjacent the filter support wall.
The filter assembly may have an upstream end and a downstream end, the longitudinally extending filter support wall may have a central portion with a plurality of openings and solid portions adjacent the upstream and downstream ends and the filter member may overlie the central portion and at least part of the upstream and downstream solid portions.
The filter assembly may have an upstream end and a downstream end, the longitudinally extending filter support wall may have a central portion with a plurality of openings and a solid portion adjacent the downstream end, the filter member may overlie the central portion and at least part of the downstream solid portion, the longitudinally extending downstream air flow passage may have an end open adjacent the upstream end and the filter member may also overlie the open end.
The longitudinally extending filter axis may be generally parallel to the motor axis.
The longitudinally extending filter axis may be generally parallel to the cyclone axis.
These and other advantages of the surface cleaning apparatus of this disclosure will be more and fully understood in conjunction with the following description of the preferred embodiments of the disclosure in which:
Referring to
As exemplified in
Surface cleaning head 12 may be any surface cleaning head known in the art. As exemplified, surface cleaning 12 has a dirty air inlet 16, a front end 18, a rear end 20 and optionally, a plurality of wheels 22. Surface cleaning head may be of any design known in the art.
Upper section 14 is moveably mounted (e.g. pivotally mounted) to surface cleaning head 12 by any means known in the art and is movable between an upright storage position as exemplified in
Upright section 14 may be any upright section known in the art. Preferably, as exemplified, upright section 14 has one or more air treatment members, such as cyclone 24, a suction motor 36 and handle 26. The suction motor 36 is provided in suction motor housing 28. The handle 26 is preferably drivingly connected to the surface cleaning head 12 to permit handle 26 to be used to steer the surface cleaning head 12. In other embodiments, it will be appreciated that suction motor 36 may be provided elsewhere, such as in surface cleaning head 12.
It will be appreciated that surface cleaning apparatus 10 may utilize any air treatment members known in the art. Preferably the air treatment member comprises at least one cyclone and may utilize a plurality of cyclonic cleaning stages. Other air treatment members such as filter bags or the like may also be used. It will also be appreciated that one or more of the air treatment members and/or the suction motor may be provided elsewhere such as in floor cleaning head 12.
As exemplified in
Accordingly, as exemplified, cyclone 24 has an air inlet and an air outlet at the upper end thereof and the dirt is collected in a separate dirt collection chamber 42 which is isolated or separated from the cyclone chamber 48. It will be appreciated that cyclone 24 may be of any other design known in the art. For example, the dirt collection chamber may comprise a lower portion of cyclone chamber 48 (e.g. a plate 44 may not be provided). Alternately, the cyclone may be an inverted cyclone (e.g. the dirt exit may be at the upper end thereof). In addition, a dirt collection chamber may be positioned exterior and adjacent to cyclone chamber 24 (such as by having a dirt exit in a sidewall of cyclone 24). It will also be appreciated that cyclone 24 may be at any particular orientation with respect to the surface cleaning apparatus 10. As shown in
At the bottom of the housing shown in
As exemplified in
A post motor filter, which may be in a post motor filter housing 32, is preferably provided. As exemplified, post motor filter housing 32 may be provided on upper section 14 and is preferably adjacent (e.g., below) the suction motor 36. Alternately, the post motor filter may be provided in the surface cleaning head or at any other desired location.
As exemplified, clean air outlet 34 comprises a grill on a forward face of post motor filter housing 32 as well as a portion of suction motor housing 28. It will be appreciated that the clean air outlet 34 may be provided on a portion or all of one or both of suction motor housing 28 and post motor filter housing 32. Alternately, the clean air outlet 34 may be provided in the surface cleaning head or at any other desired location.
In operation, air is drawn in through dirty air inlet 16 and transferred via one or more conduits to cyclone 24. The air exits cyclone 24 via cyclone air outlet 38 and is then conveyed by one or more conduits, preferably through a pre motor filter, to a position above suction motor 36. For example, as exemplified in
Referring again to
Filter 64, may be considered to have an upstream end 94 and a downstream end 96. As shown in
Longitudinally extending filter 64 has a filter axis 70 and is oriented such that the upstream face 76 is parallel to the direction of the air stream when it reaches the upstream end of filter 64. As exemplified, filter axis 70 is parallel to cyclone axis 50 and suction motor axis 52. Further, filter axis 70 is common (i.e., co-axial) with suction motor axis 52 and is laterally offset from cyclone axis 50. In an alternate embodiment, it will appreciated that filter axis 70 may be common with cyclone axis 52 and may be laterally offset from suction motor axis 52. Further, it will be appreciated that all three axes 50, 52 and 70 may be laterally offset from each other but generally parallel or they may be co-axial.
Referring still to
In contrast, pre-motor filter 62 is a longitudinally extending filter member which has an upstream surface 76 and a downstream surface 78. The upstream and downstream surfaces are exemplified as being parallel to the filter axis 70 as well as parallel to cyclone axis 50 and motor axis 52. Accordingly, the air may travel through plenum 60 to the longitudinally extending upstream air-flow passage 62 and then travel inwardly or transversally through filter 64. As such, a larger upstream surface area may be presented to the post-cyclone air-flow stream. Accordingly, upstream surface 76 defines a longitudinally extending peripheral wall of filter 64.
It will be appreciated that upstream and/or downstream surfaces 76 and 78 may not be exactly parallel to one or both cyclone axis 50 and suction motor 52. Further, it will be appreciated that the air may not travel exactly transversely through filter 64. For example, as exemplified by the arrows C, the air may travel inwardly and downwardly (i.e. in the direction of suction motor 36) through filter 64.
It will be appreciated that, in an alternate embodiment, the air may travel transversely or outwardly through longitudinally extending filter media 64. For example, the air exiting conduit 56 may be in fluid communication with the center passage in filter 64 and then be directed outwardly through filter 64 to the passage adjacent the outer surface. In such a case, reference numeral 66 would define the longitudinally extending upstream air flow passage and reference numeral 62 would denote the longitudinally extending downstream air flow passage. In either case, the inner or outer longitudinally extending surface of filter 64 would be presented as an upstream air flow side of filter 64 and would provide an enhanced surface area for filtration. In either case, it will be appreciated that a substantially larger surface area may be provided for filtration than by the use of a disc shaped filter 68. For example, if disc shaped filter 68 would to have the same upstream surface area as filter 64, then the diameter of filter 68 would have to be substantially increased which would require a substantial increase in the width or diameter of upper housing 14. However, the diameter or footprint of upper housing 14 may be maintained relatively small by increasing the height of filter 64 and utilizing its longitudinally extending sides as the upstream surface.
An alternate embodiment is exemplified in
Still referring to
In a preferred embodiment, filter 64 is annular or substantially annular. As exemplified in
In accordance with another preferred embodiment, the longitudinally extending filter media 64 is preferably provided with or mounted on a filter holder 82. As will be appreciated, the filter 64 may be relatively long and hollow and may be made of foam. As such, under the air flow induced in a vacuum cleaner, substantial pressure may be applied to upstream surface 76 of filter 64 thereby possibly deforming and, in an extreme case, collapsing filter 64 (e.g. the interior air flow passage 66 may be reduced in the cross section area and it might even be closed). Accordingly, a filter holder is preferably provided to maintain the shape of filter 64. It will be appreciate that the filter holder may be of various shapes and configurations depending upon the shape of filter 64. In the exemplified embodiment of
As exemplified in particular in
Preferably, filter 64 is compressed against support wall 84. The compression of the foam assists in maintaining foam 64 against support wall 84 and will therefore assist in preventing air bypassing filter 64. For example, if the foam fits loosely against support wall 64, it is possible that some air may flow between upstream surface 76 and support wall 84 if there is a gap therebetween or if there is a loose fit. Preferably, the compression of the foam is from 0.1-10 millimeters, more preferably from 0.5-5 millimeters and, more preferably from 1-2.5 millimeters. It is preferred to limit the compression of the foam since excessive compression may result in closing a number of the open cells in the foam which will increase the back pressure through the vacuum cleaner.
It will be appreciated that support wall 84 is configured to allow air flow therethrough. In the exemplified embodiment of
Preferably, filter 64 or the filter assembly is provided with a handle to manipulate the filter assembly. An advantage of the handle is that a consumer need not touch filter 64 and, in particular, upstream surface 76 of filter 64 when removing filter 64 for cleaning or replacement. As exemplified, handle 92 is provided in a recess 90 provided at an upper and (e.g. the upstream end) of support wall 84. It will be appreciated that handle 92 need not be recessed interior of filter 64 (see for example
It is preferred that filter 64 and/or the filter assembly be configured so as to inhibit and, preferably prevent, air from following a shorter flow route through the filter 64. In other words, filter 64 and/or the filter assembly may be designed such that the air will travel a minimum desired distance through filter 64. For example, if perforations 88 extended all the way to upstream end 94, it is possible that some air may travel through upstream face 98 of filter 64 and travel directly through perforations 88 into longitudinally extending airstream airflow passage 66.
In one embodiment, such a short flow route through the filter 64 may be inhibited by providing an upstream portion 102 of support wall 84 that is solid or air impermeable. Accordingly, as show in
In order to prevent or inhibit bypass of air or the short circuiting of air through filter 64, at the downstream end 96 of filter 64, it is preferred to have a base 86 upon which downstream face 100 of filter 64 seats. In addition, it is preferred that downstream portion 104 of support wall 84 is also solid or air impervious (i.e. there are no perforations 88). Accordingly, the travel of air around downstream face 100 of filter 64 into downstream airflow passage 66 may be inhibited.
Accordingly, it is preferred that a portion of either longitudinal end of support wall 84 not be air impermeable. In a particularly preferred embodiment, both upstream and downstream portions 102 and 104 of support wall 84 are air impervious, however, it would appreciated that, in some embodiments, one or both of upstream and downstream portions 102 and 104 may permit airflow therethrough. Accordingly, upstream and downstream portions 102 and 104 may be solid portions and the remainder of support wall 84 positioned there between may be considered a central portion which is provided with the opening or perforations 88.
Preferably, upstream portion 102 is from 0.1-25, more preferably 2-15 and, most preferably 8-15 millimeters in length. Similarly, downstream portion 104 preferably has a length which is selected from the same ranges.
Alternate constructions of filter 64 and filter holder 82 may be used so as to reduce the bypass or short circuiting of air through filter 64. For example, as exemplified in
A further alternate embodiment is shown in
In another alternate embodiment, as exemplified in
It is also preferred that the filter 64 is compressed in the longitudinal direction. For example, upstream wall 106 may be utilized to compress filter 64 longitudinally between base 86 and upstream wall 106. The filter 64 may be compressed longitudinally from 0.1-10, preferably from 0.5-5, and most preferably from 1-2.5 millimeters.
It will be appreciated that, in some embodiments, filter holder 82 may be provided on or in a filter holder mount 112. Preferably, the filter holder mount 112 is utilized to define a wall of one of the upstream and downstream air flow passages 62, 66. For example, as exemplified in
In another preferred embodiment, a dirt collection recess 122 may be provided. Such a recess is exemplified in
It will accordingly be appreciated that the filter assembly may comprise filter 64 together with filter holder 82 and filter holder mount 112. However, as also exemplified herein, a filter holder mount 112 is not required and the filter assembly may comprise filter 64 and filter holder 82. In such a case, the filter housing 58 itself, or at some other portion of the surface cleaning apparatus, may be utilized to define one of the air flow passages 62, 64.
It will be appreciated that filter 64 may be provided at various locations in the surface cleaning apparatus. For example, in addition to being position above or below cyclone 24, filter 64 may be position adjacent (i.e. laterally spaced from) cyclone 24. Such an embodiment is exemplified in
It will also be appreciated that in an embodiment wherein the filter 64 is adjacent cyclone 24, filter 64 may still be a hollow body. Such a configuration is shown in
Filter 64 may be made by various techniques. For example, if filter 64 is a hollow body as exemplified in
It will be appreciated that, in some embodiments, a secondary filter may be provided co-extensively with filter 64. For example a second filter media may be provided on one of the upstream and downstream surfaces 76, 78 of filter 64 and, preferably, on the downstream surface 78. Preferably, the additional filter member will filter particulate matter having a different size from that of filter 64. If the second filter member is on the downstream surface, then it will preferably filter finer particulate matter and, if it is provided on the upstream face, then it will filter coarser particulate matter. In a particularly preferred embodiment, the secondary filter member is provided on downstream surface 78 and comprises a felt filter.
It will be appreciated that the following claims are not limited to any specific embodiment disclosed herein. Further, it will be appreciated that one or more of the features disclosed herein may be used in any particular combination or sub-combination. Further, what has been described herein has been intended to be illustrative of the invention and non-limiting and it will be understood by a person skilled in the art that other variants and modifications may be made without departing from the scope of the invention as defined in the claims appended hereto.
Claims
1-32. (canceled)
33. A surface cleaning apparatus comprising:
- a) an air flow passage extending from a dirty air inlet to a clean air outlet;
- b) a cyclone positioned in the air flow passage and having a cyclone air inlet, a cyclone air outlet and a cyclone axis;
- c) a suction motor positioned in the air flow passage and having a longitudinally extending motor axis; and,
- d) a filter assembly downstream of the cyclone air outlet and upstream of the suction motor, the filter assembly comprising: i) a longitudinally extending first filter media configured as a hollow body and having a filter axis, an outer upstream surface and an inner downstream surface positioned transversely inwardly from the outer upstream surface; ii) a longitudinally extending secondary filter positioned interior the longitudinally extending first filter media, the longitudinally extending secondary filter configured as a hollow body and having an outer upstream surface positioned transversely inwardly from the inner downstream surface of the longitudinally extending first filter media and an inner downstream surface positioned transversely inwardly from the outer upstream surface of the longitudinally extending secondary filter; and, iii) an inner longitudinally extending downstream air flow passage positioned transversely inwardly from the inner downstream surface of the longitudinally extending secondary filter,
- wherein the longitudinally extending filter axis is generally parallel to the motor axis and intersects the suction motor and wherein the secondary filter filters finer particulate matter than the longitudinally extending first filter media.
34. The surface cleaning apparatus of claim 33 wherein the longitudinally extending first filter media is substantially annular.
35. The surface cleaning apparatus of claim 34 wherein the inner downstream surface is circular in transverse section.
36. The surface cleaning apparatus of claim 33 wherein the longitudinally extending filter axis is coaxial with the motor axis.
37. The surface cleaning apparatus of claim 33 wherein the longitudinally extending first filter media comprises a foam filter.
38. The surface cleaning apparatus of claim 33 wherein the cyclone axis is generally parallel to the motor axis.
39. The surface cleaning apparatus of claim 38 wherein the cyclone axis is generally co-axial with the motor axis.
40. A surface cleaning apparatus comprising:
- a) an air flow passage extending from a dirty air inlet to a clean air outlet;
- b) a cyclone positioned in the air flow passage and having a cyclone air inlet, a cyclone air outlet and a cyclone axis;
- c) a suction motor positioned in the air flow passage and having a longitudinally extending motor axis; and,
- d) a filter assembly downstream of the cyclone air outlet and upstream of the suction motor, the filter assembly comprising a longitudinally extending first filter media configured as a hollow body and having a filter axis, an outer upstream surface, an inner downstream surface positioned transversely inwardly from the outer upstream surface and a transversely positioned inner longitudinally extending downstream air flow passage
- wherein the longitudinally extending filter axis is generally parallel to the motor axis and intersects the suction motor.
41. The surface cleaning apparatus of claim 40 wherein the longitudinally extending first filter media is substantially annular.
42. The surface cleaning apparatus of claim 40 wherein the inner downstream surface is circular in transverse section.
43. The surface cleaning apparatus of claim 40 wherein the longitudinally extending filter axis is coaxial with the motor axis.
44. The surface cleaning apparatus of claim 40 wherein the longitudinally extending first filter media comprises a foam filter.
45. The surface cleaning apparatus of claim 40 further comprising a secondary filter provided co-extensively with the longitudinally extending first filter media.
46. The surface cleaning apparatus of claim 45 wherein the secondary filter is provided on one of the outer upstream surface and the inner downstream surface of the longitudinally extending first filter media.
47. The surface cleaning apparatus of claim 46 wherein the secondary filter is provided on the inner downstream surface of the longitudinally extending first filter media.
48. The surface cleaning apparatus of claim 47 wherein the secondary filter filters finer particulate matter than the longitudinally extending first filter media.
49. The surface cleaning apparatus of claim 40 further comprising a secondary filter downstream of the longitudinally extending first filter media and coaxial therewith.
50. The surface cleaning apparatus of claim 49 wherein the secondary filter filters finer particulate matter than the longitudinally extending first filter media.
51. The surface cleaning apparatus of claim 40 wherein the cyclone axis is generally parallel to the motor axis.
52. The surface cleaning apparatus of claim 51 wherein the cyclone axis is generally co-axial with the motor axis.
Type: Application
Filed: Oct 21, 2016
Publication Date: Mar 9, 2017
Inventor: Wayne Ernest Conrad (Hampton)
Application Number: 15/331,229