The present invention relates to floor cleaners.
In one embodiment a floor cleaner is disclosed, the floor cleaner including a fluid flow path extending from a dirty air inlet to a clean air outlet, a fluid flow motor positioned in the fluid flow path, a separator housing, and a cylindrical filter chamber housing a cylindrical filter media. The separator housing includes a separator air inlet in communication with the dirty air inlet and a separator air outlet. The cylindrical filter chamber includes a first end, a second end, and a cylindrical sidewall extending between the first and second ends in a longitudinal direction. The cylindrical filter chamber includes a filter inlet tangential to the cylindrical sidewall and in fluid communication with the separator air outlet. The cylindrical filter media is positioned in the filter chamber. The cylindrical filter media includes an upstream portion and a downstream portion. The upstream portion is spaced from the cylindrical sidewall between the first end and the second end. The downstream portion forms a portion of the fluid flow path upstream of the fluid flow motor. A longitudinal height of the filter inlet is at least 60% of a longitudinal height of the upstream portion of the filter media between the first end and the second end.
In another embodiment a floor cleaner is disclosed including a fluid flow path extending from a dirty air inlet to a clean air outlet, a fluid flow motor positioned in the fluid flow path, a separator housing in the fluid flow path, and a cylindrical filter chamber. The separator housing includes a separator air inlet and a separator air outlet. The cylindrical filter chamber includes a first end, a second end, and a cylindrical sidewall extending between the first and second ends in a longitudinal direction. The cylindrical filter chamber further includes a cylindrical filter media in the fluid flow path downstream of the separator housing and upstream of the fluid flow motor. The cylindrical filter is spaced apart from the cylindrical sidewall by a gap. The length of the gap is less than 30% of a diameter of the cylindrical filter media. The filter chamber includes a filter inlet edge that extends into the filter chamber such that a radial distance between the filter media and the cylindrical sidewall is greater than a radial distance between the filter media and the filter inlet edge.
In another embodiment a floor cleaner is disclosed including a fluid flow path extending from a dirty air inlet to a clean air outlet, a fluid flow motor positioned in the fluid flow path, a separator housing, and a cylindrical filter chamber. The separator housing includes a separator air inlet in communication with the dirty air inlet, a separator air outlet, an upper end, and a lower end. The separator housing further includes a debris collection chamber. A door is coupled to the lower end of the separator housing and is movable from a closed position to an open position to empty the debris collection chamber through the lower end of the housing. The cylindrical filet chamber includes a first end, a second end, and a cylindrical sidewall extending between the first and second ends. The cylindrical filter chamber further includes a cylindrical filter media in the fluid flow path downstream of the separator housing and upstream of the fluid flow motor. The cylindrical sidewall includes a filter inlet that enters the cylindrical sidewall tangentially, communicating the separator housing and the cylindrical filter chamber. The door on the lower end of the separator housing forms the first end of the filter chamber.
In another embodiment a floor cleaner is disclosed including a fluid flow path extending form a dirty air inlet to a clean air outlet, a fluid flow motor positioned in the fluid flow path, a separator housing, and a cylindrical filter chamber housing an annular filter media. The separator housing includes a separator air inlet in communication with the dirty air inlet, and a separator air outlet. The cylindrical filter chamber includes an openable first end, a second end, and a cylindrical sidewall extending between the first and second ends. The second end has a filter chamber air outlet upstream of the fluid flow motor. The filter chamber has a filter inlet tangential to the cylindrical sidewall and in fluid communication with the separator air outlet. The annular filter media is positioned in the filter chamber. The filter media has an upstream portion spaced from the cylindrical sidewall between the first end and the second end, and a downstream portion forming a portion of the fluid flow path in communication with the chamber air outlet. The first end of the filter chamber is formed by a portion of the separator housing and the separator housing is separable from the filter chamber to open the first end of the filter chamber.
Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.
In the illustrated embodiment shown in
In order to limit the amount of air flow bypassing the filter media 22 and directly entering the air passageway 55 or filter chamber outlet 54 without flowing through the filter media 22, an upper side 29a and a lower side 29b of the filter media 22 or filter frame 21 is positioned in sealing engagement with the filter chamber 20 and/or the separator housing 14 configured to direct air from the filter inlet 30 through the filter media 22. Stated another way, the filter media 22 is positioned in the filter chamber 20 configured to inhibit air from passing around the filter media during use.
In one embodiment, the lower side 29b of the filter media 22 is in sealing engagement with the bottom portion 33 of the filter frame 21 and the bottom portion 33 of the filter frame 21 is in sealing engagement with the second end 28 of the filter chamber 20. In another embodiment, the lower side 29b of the filter frame 21 is in sealing engagement with the second end 28 of the filter chamber 20 via a filter frame seal 35. The upper side 29a of the filter and a top of the air passageway 55 are also closed or sealed in order to inhibit air bypassing the filter media 22 and directly entering the air passageway 55.
The upper side 29a of the filter and the top of the air passageway 55 may be sealed by the same closure or by separate closures. In the illustrated embodiment, the top portion 31 of the filter frame closes the top of the air passageway 55 and a bottom side of the separator housing 14 seals the upper side 29a of the filter media 22. In the illustrated embodiment, the separator housing 14 includes an openable door 18 on the bottom side of the separator housing 14, and the upper side 29a of the filter media 22 is sealed by the openable door 18. When the separator housing 14 is removed, the filter media 22 is accessible for cleaning and service. In one embodiment shown in
The cylindrical filter chamber 20 and filter 22 are in the fluid flow path downstream from the separator housing 14 and upstream from the fluid flow motor 12. The cylindrical sidewall 24 of the filter chamber 20 extends between the first end 26 and the second end 28. The filter media 22 is positioned in the filter chamber 20, the filter media having an upstream portion 19a and a downstream portion 19b. The upstream portion 19a is spaced from the cylindrical sidewall 24 between the first end 26 and the second end 28, and the downstream portion 19b forms a portion of the fluid flow path upstream of the filter chamber outlet 54 and the fluid flow motor 12. In the illustrated embodiment, cylindrical filter media 22 is annular, wherein the upstream portion 19a of the cylindrical filter includes the outer cylindrical surface 19a of the filter media and the downstream portion 19b includes the inner annular surface 19b of the filter media 22.
When the air flow enters the tangential inlet 30 of the filter chamber 20, the air flows along the sidewall 24 and debris may settle from the airflow. In one embodiment, as shown in
In the embodiment shown in
In the illustrated embodiment, the first end 26 of the filter chamber 20 is located under the separator housing 14 and the dirt collection chamber 16. In one embodiment, the dirt collection chamber 16 is separate from the separator housing 14, and the first end 26 of the filter chamber 20 is located under the dirt collection chamber 16. In the illustrated embodiment, the second end 28 of the filter chamber is located above the fluid flow motor 12 and includes the filter chamber outlet 54 fluidly communicating the downstream portion 19b of the filter with the motor 12. The fluid flow motor 12 extends along a motor axis 82. As shown in
The inlet 30 directs airflow into the filter chamber 20 generally tangentially to the cylindrical sidewall 24. The tangential inlet 30 fluidly communicates the separator housing 14 and the filter chamber 20. In particular, an airflow passage 61 extends between the clean air outlet 40 of the separator housing 14 to a filter inlet duct 62 forming the tangential inlet 30 of the filter chamber 20. The tangential inlet 30 is formed by an outlet aperture of the filter inlet duct 62 extending through the sidewall 24. The filter inlet duct 62 includes an inner wall 64 forming an inlet edge 66 of the filter inlet 30, an outer wall 68, a top wall 70 extending to and forming a top edge 50 of the filter inlet, and a bottom wall 72 forming a bottom 52 of the filter inlet. In the illustrated embodiment, the inner wall 64 extends into the filter chamber such that the radial dimension between the filter media 22 and the sidewall 24 is greater than the radial dimension between the filter media 22 and the inlet edge 66 of the filter inlet. The filter frame 21 and the filter chamber 20 include a mating notch and tab arrangement such that when the filter frame 21 is placed into the filter chamber 20, alignment of the notch and tab will properly orient the filter frame 21 within the filter chamber 20 to thereby align an opening 74 (
In order to increase the efficiency and performance of the filtration system, a height of the tangential inlet aperture 30 is increased to be a substantial portion of a height of the filter media 22. This allows a steady stream of air to flow from the inlet 30 into the filter media 22. By increasing an inlet height H1 such that it is a substantial portion of a filter media height H2, the speed of air entering the filter chamber 20 and filter media 22 is reduced. The air speed is reduced because the increased inlet height H1 provides a less restrictive air passageway. The reduced air speed entering the filter results in less air bypassing the filter media 22 to enter the air passageway 55 and more air flowing through the filter media 22. The increased air flow through the filter media 22 improves filtration performance. It has been found that when the inlet height is shorter relative to the filter media 22, the speed of the air entering the filter chamber 20 is greater because the inlet is more restrictive, tending to increase suction (decrease pressure) increasing the pressure difference between the inside of the system and the atmosphere, which may enable air to draw through weaker sealing connections bypassing the filter media 22, resulting in a decrease in filtration. When the air speed is greater, in certain configurations air is able to leak between the filter media and the sealing surfaces, such as the top portion 31 of the filter frame or the openable door 18 of the separator housing, to enter the air passageway 55 directly and bypass the filter media 22. Additionally, it has been found that when the height of the inlet H1 is 50% or less than the height of the filter media exposed to air flow in use H2, filtration performance is significantly reduced because the air speed is greater and there is less filter surface area exposed to the inlet for filtration. In the illustrated embodiment, the longitudinal height H1 of the inlet 30 from the top edge 50 to the bottom 52 is a substantial portion of the longitudinal height of the cylindrical filter media 22 exposed to air flow in use H2. In one embodiment, the longitudinal height H1 is at least 60% of the longitudinal height H2. In one embodiment, the longitudinal height H1 is at least 75% of the longitudinal height H2. In addition to decreased air speed entering the filter chamber 20, filtration is improved by a resulting increase in the surface area of the filter media 22 that is exposed to the inlet 30 air flow. This greater surface area allows more air flow through the filter media 22.
Additionally, the height of the tangential inlet H1 is a substantial portion of a height of the filter chamber H3 (
In one embodiment, the filter chamber 20 is configured to provide a gap 56 between the filter 22 and the cylindrical sidewall 24 of the filter chamber to provide desired air flow around the filter 22. Desired filtration has been achieved with a gap 56 in the range of 5 millimeters to 20 millimeters. In one alternative, the gap 56 between the filter 22 and the adjacent sidewall 24 is between 5 millimeters and 10 millimeters. In another alternative, the gap 56 between the filter 22 and the adjacent sidewall 24 is larger than 5 millimeters to provide desired airflow around the filter 22.
In one embodiment, the gap 56 between the filter 22 and the cylindrical sidewall 24 of the filter chamber can be measured as a percentage of a cross-sectional diameter of the filter D1. In one embodiment, the gap 56 is less than 30% of the cross-sectional diameter of the filter D1. In an alternate embodiment, the gap 56 between the filter 22 and cylindrical sidewall 24 is less than 15% of the cross-sectional diameter of the filter D1. In another embodiment the gap 56 is between 1% and 25% of the cross-sectional diameter of the filter D1. The gap 56 allows air flow around the cylindrical filter 22. When the gap 56 is too small a percentage of the filter diameter D1, air may tend to overcome the sealing surfaces, and bypass the filter 22. This results in air exiting through the filter chamber outlet 54 without being adequately filtered through the filter media 22. When the gap 56 is too large as a percentage of the filter diameter D1, the speed of the air in the filter chamber 20 is more variable than desired. The air speed is lower near the sidewall 24 and higher near the filter 22, resulting in worse overall filtration. We have found desired filtration has been achieved with the gap 56 is in the range of 5% to 30% of the diameter of the filter D1.
The gap 56 can also be measured as a ratio of the diameter of the filter D1 relative to a diameter of the filter chamber D2. In one embodiment, the ratio of the diameter of the filter D1 to the diameter of the filter chamber D2 is between 60% and 90%. In an alternate embodiment, the ratio of the filter diameter D1 to the filter chamber diameter D2 is between 75% and 90%. This ratio ensures substantial constant speed in the filter chamber and low pressure drop as air passes through, which provides high filtration efficiency.
In one embodiment, the cylindrical filter 22 includes a first cylindrical filter 22a and a second cylindrical filter 22b. The second cylindrical filter 22b is nested within the first cylindrical filter 22a. In one embodiment, the height of the first cylindrical filter 22a is greater than the height of the second cylindrical filter 22b. In a use position, the upper sides 29a of the first and second cylindrical filters 22a, 22b are compressed and sealed as discussed above, such as by the top portion 31 of the filter frame or by the bottom door 18 of the dirt collection chamber. The filter 22 may be any desired filter media, including pleated or non-pleated, non-woven fiber, foam, high-efficiency particular air filter (HEPA), or other media. The first cylindrical filter 22a and the second cylindrical filter 22b may be made of the same material or different material.
In the illustrated embodiment, the tangential inlet 30 to the filter chamber 20 has a longitudinal height H1 from the top edge 50 to the bottom edge 52 that is greater than the width from the inlet duct inner wall 64 to the outer wall 68 at the tangential inlet 30. In one embodiment, the height H1 from the top edge 50 to the bottom edge 52 is at least twice the width of the inlet duct from the inner wall 64 to the outer wall 68. As a result of this ratio, the airflow path entering the filter media 22 from the separator housing 14 leaves the separator housing 14 with a lower pressure drop compared to arrangements where the width of the inlet is nearly equal to the height. This lower pressure drop produces adequate air flow for more efficient filtration.
Various features and advantages of the invention are set forth in the following claims.
This application claims priority to U.S. Provisional Patent Application No. 62/937,952, filed Nov. 20, 2019, the entire contents of which are hereby incorporated by reference herein.
Number | Date | Country | |
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62937952 | Nov 2019 | US |