US20210330161A1

US20210330161A1 - Rotary working element

Info

Publication number: US20210330161A1
Application number: US17/239,082
Authority: US
Inventors: Robert McRorie; Rafael Davila
Original assignee: Techtronic Cordleess Gp; Techtronic Floor Care Technology Ltd
Current assignee: Techtronic Floor Care Technology Ltd
Priority date: 2020-04-24
Filing date: 2021-04-23
Publication date: 2021-10-28
Also published as: WO2021217029A1; US20210330151A1; WO2021217033A1

Abstract

A floor cleaner includes a suction source, a body, and a rotary working element. The body includes a working element chamber having an opening facing toward a surface to be cleaned and a suction inlet in fluid communication with the suction source. The rotary working element is positioned within the working element chamber and includes a body rotatable about an axis having silicone features extending outwardly from the body to contact the surface to be cleaned though the opening.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application No. 63/015,232, filed Apr. 24, 2020 and to U.S. Provisional Patent Application No. 63/036,714, filed Jun. 9, 2020, the entire contents all of which are hereby incorporated by reference herein.

BACKGROUND

The present invention relates to a rotary working element for a cleaning device.

SUMMARY

In one embodiment, the invention provides a floor cleaner including a suction source, a body, and a rotary working element. The body includes a working element chamber having an opening facing toward a surface to be cleaned and a suction inlet in fluid communication with the suction source. The rotary working element is positioned within the working element chamber and includes a body rotatable about an axis having silicone features extending outwardly from the body to contact the surface to be cleaned though the opening.
Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a cleaning device according to one embodiment of the invention.

FIG. 2 is a view similar to FIG. 1 with a cover removed exposing a rotary working element.

FIG. 3 is a cross-section view taken along line 3-3 of FIG. 1 with the rotary working element not shown.

FIG. 4 is a view similar to FIG. 3 showing a suction inlet and the rotary working element removed with a single convergence area.

FIG. 5 is a perspective view of the rotary working element shown in FIG. 4.

FIG. 6 is a front view of the rotary working element of FIG. 5.

FIG. 7 is a cross-section view taken along line 7-7 of FIG. 6.

FIG. 8 is a perspective view of another embodiment of a rotary working element.

FIG. 9 is a front view of the rotary working element of FIG. 8.

FIG. 10 is a perspective view of another embodiment of a rotary working element.

FIG. 11 is a front view of the rotary working element of FIG. 10.

FIG. 12 is a perspective view of another embodiment of a rotary working element.

FIG. 13 is a front view of the rotary working element of FIG. 12.

FIG. 14 is a cross-section view taken along line 14-14 of FIG. 13.

FIG. 15 is a view similar to FIG. 4 showing two suction inlets and another embodiment of a rotary working element with two convergence areas.

FIG. 16 is a perspective view of rotary working element of FIG. 15.

FIG. 17 is a front view of the rotary working element of FIG. 16.

FIG. 18 is a view similar to FIG. 15 showing two suction inlets and another embodiment of a rotary working element with four convergence areas.

FIG. 19 is a perspective view of the rotary working element of FIG. 18.

FIG. 20 is a front view of the rotary working element of FIG. 18.

FIG. 21 is a perspective view of another embodiment of a rotary working element.

FIG. 22 is a front view of the rotary working element of FIG. 21.

FIG. 23 is a perspective view of another embodiment of a rotary working element.

FIG. 24 is a front view of the rotary working element of FIG. 23.

FIG. 25 is a perspective view of another embodiment of a rotary working element.

FIG. 26 is a front view of the rotary working element of FIG. 25.

FIG. 27 is a cross-section view taken along line 27-27 of FIG. 26.

FIG. 28 is a perspective view of another embodiment of a rotary working element.

FIG. 29 is a front view of the rotary working element of FIG. 28.

FIG. 30 is a cross-section view taken along line 30-30 of FIG. 29.

FIG. 31 is a perspective view of another embodiment of a rotary working element.

FIG. 32 is a front view of the rotary working element of FIG. 31.

FIG. 32a is a detail view of the rotary working element of FIG. 32.

FIG. 33 is a cross-section view taken along line 30-30 of FIG. 32.

FIG. 34 is a perspective view of another embodiment of a rotary working element.

FIG. 35 is a front view of the rotary working element of FIG. 34.

FIG. 36 is a cross-section view taken along line 36-36 of FIG. 35.

FIG. 37 is a perspective view of another embodiment of a rotary working element.

FIG. 38 is a front view of the rotary working element of FIG. 37.

FIG. 39 is a cross-section view taken along line 39-39 of FIG. 38.

FIG. 40 is a perspective view of another embodiment of a rotary working element.

FIG. 41 is a front view of the rotary working element of FIG. 40.

FIG. 42 is a cross-section view taken along line 42-42 of FIG. 41.

DETAILED DESCRIPTION

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.
FIG. 1 illustrates a floor cleaning device 10. The floor cleaning device 10 is illustrated as an upright hard floor cleaner including an upper body 12 coupled to a surface cleaning head 14 with a steerable joint 16 for rotation and pivoting. The upper body 12 rotates relative to the surface cleaning head 14 in a front-to-back direction between an upright storage position (as shown in FIG. 1) and an inclined in-use position where the upper body 12 is rotated downwardly closer to the surface to be cleaned 18. When in the inclined position, the upper body 12 pivots relative to the surface cleaning head 14 in a side-to-side direction between a leftward-leaning direction and a rightward-leaning direction. The upper body 12 includes a user-graspable handle 20 allowing an operator to steer the surface cleaning head 14 around obstacles as the surface cleaning head 14 is moved over the surface to be cleaned 18. Although the invention is described for use in an upright hard floor cleaner, the invention is not limited to only this use. Rather, the invention could be used with other floor cleaning devices such as upright carpet extractors, portable extractors, canister-type cleaners, wet/dry utility vacuum cleaners, and the like.
With further reference to FIG. 2, the surface cleaning head 14 includes a housing 22, rear wheels 24 supporting the housing 22 for movement across the surface to be cleaned 18, a working element chamber 26, a suction inlet 28 disposed at the rear of the working element chamber 26, an opening 30 facing the surface to be cleaned 18, a rotary working element 32 rotatably mounted within the working element chamber 26, a distribution nozzle 34, and a motor (not shown) for selectively rotating the rotary working element 32 about an axis 36. In the illustrated embodiment, the working element chamber 26 and suction inlet 28 are defined by a removable cover 38. When the cover 38 is removed from the housing 22, access to the rotary working element 32 is provided allowing an operator to clean the rotary working element 32 or remove the rotary working element 32 for maintenance or replacement.
The upper body 12 includes a housing 40, a suction motor (not shown) within the housing 40, a pump (not shown) within the housing 40, a removable battery 42 received within the upper body 12 to power the suction motor, the motor, and the pump, a supply tank 44 for containing cleaning liquid for distribution onto the surface to be cleaned 18 through the pump and distribution nozzle 34, and a recovery tank 46 in fluid communication with the suction motor downstream and the opening 30 and suction inlet 28 upstream. When the suction motor is powered by the battery 42, dirty air and liquid is drawn into the opening 30 and the suction inlet 28 and delivered to the recovery tank 46 where liquid and debris is separated from the air such that the liquid and debris is stored in a collection area and the separated air is drawn out of the recovery tank 46 toward the suction motor to be exhausted from the cleaning device 10.
As shown in FIG. 3, the working element chamber 26 includes the suction inlet 28 centered along the axial length of the working element chamber 26. The suction inlet 28 is fluidly coupled to a flexible hose 48 or duct leading to the recovery tank 46.
With further reference to FIG. 4, the rotary working element 32 is removably coupled to housing 22 by connections at each end of the rotary working element 32. The first end of the rotary working element 32 includes a receptacle 50 to receive a corresponding drive member 52 driven by the motor through a belt or other transmission (not shown). The second end of the rotary working element 32 includes a bearing cap 54 allowing rotation of the rotary working element 32 while the bearing cap 54 remains stationary. The bearing cap 54 is removably fixed to the housing 22. Rotation of the drive member 52 in turn rotates the rotary working element 32. In illustrated embodiments, the bearing cap 54 includes a flexible and resilient tab 56 that projects upwardly for the operator to grab and pull to lift the bearing cap 54 and the second end of the rotary working element 32 free from the housing 22 thereby allowing the operator to slide the rotary working element 32 off of and away from the drive member 52.
FIGS. 5 and 6 illustrate that the rotary working element 32 is a rotary squeegee 58 having a body 60 rotatable about the axis 36 having features, squeegee elements 62 in this embodiment, extending outwardly from the body 60 to contact the surface to be cleaned 18 through the opening 30. The squeegee element 62 is arranged around the body 60 in a helical pattern about the axis 36. The squeegee element 62 includes a base portion 64 connected to the body 60 and a squeegee edge 66 configured to wipe the surface 18 as the rotary squeegee 58 rotates. The radial distance from the axis 36 to the squeegee edge 66 is constant along the squeegee element 62. The rotary squeegee 58 can include a single continuous helical segment across the entire axial length of the rotary squeegee or it can be segmented into multiple discrete segments 68.
In the illustrated embodiments, the squeegee element 62 defines a squeegee axis 100 extending outwardly from the body 60. In the embodiment illustrated in FIGS. 25-30 and 37-42, the squeegee edge 66 further includes a flange 65 disposed adjacent the squeegee edge 66. In the illustrated embodiments, the flange 65 is positioned along an outer circumference of the rotary squeegee 58. In one embodiment, the flange 65 is offset from the outer circumference of the rotary squeegee 58.
The flange 65 extends forwardly along a flange axis 102, away from the squeegee axis 100 in the direction of rotation. In one embodiment, the flange 65 extends between 2 and 10 millimeters away from the squeegee element 62. In one embodiment, the flange 65 extends between 10 and 20 millimeters away from the squeegee element 62. The flange axis 102 is angled forwardly relative to the squeegee axis 100. In one embodiment, the angle of the flange axis 102 relative to the squeegee axis 100 is between 60 and 75 degrees. In one embodiment, the angle of the flange axis 102 relative to the squeegee axis 100 is between 75 and 90 degrees. In one embodiment, the angle of the flange axis 102 relative to the squeegee axis 100 is between 90 and 105 degrees. The flange axis 102 does not intersect the body 60 of the rotary squeegee. The flange 65 assists in liquid and debris pick up by directing the gathered liquid and debris into the suction inlet 28.
In the embodiments illustrated in FIGS. 31-42, the squeegee element 62 includes one or more ribs 67 integral with the squeegee element 62. The ribs 67 extend between a front surface 71 of the squeegee element and/or a back surface 73 and the core 30. In the illustrated embodiments, the support ribs 67 extend along the squeegee element 62 from the base portion 64 to the squeegee edge 66. The ribs 67 help support, strengthen, and reinforce the squeegee element 62. The support of the ribs 67 limits the flexing of the squeegee element 62, which improves surface pick up and cleaning performance. In one embodiment, the ribs 67 extend from the base portion 64 to the squeegee edge 66. In the embodiments illustrated in FIGS. 31-42, the ribs 67 extend on a front surface 71 of the squeegee element 62, in a direction of rotation. In one embodiment, the ribs 67 extend on a back surface 73 of the squeegee element 62, in a direction opposite of rotation. In one embodiment, the ribs 67 are spaced from adjacent ribs by between 2 and 40 millimeters. In another embodiment, the support ribs 67 are spaced from adjacent support ribs by between 5 and 20 millimeters.
In the embodiment illustrated in FIG. 32a , the ribs 67 extends from the front surface 71 in a forward direction F. In another embodiment (not shown), the ribs 67 extend at an angle to the forward direction F, and may extend generally perpendicular to the squeegee element 62. In one embodiment, the front edges of the ribs 67 extend at the same rake angle as the squeegee element 62. Said another way, when looking at a cross-sectional view, the front edges of the ribs 67 extend roughly parallel to the squeegee element 62. In the embodiment illustrated in FIGS. 31-42, the ribs 67 extend at a different rake angle than the squeegee element 62. This is illustrated in the cross-sectional views of FIGS. 33, 36, 39, and 42, where the ribs 67 extend at an angle 69 different from the squeegee element 62. In the embodiments illustrated in FIGS. 37-42, the squeegee element 62 includes both the plurality of ribs 67, as well as the flange 65 extending from the squeegee edge 66.
The squeegee elements 62 are divided into a first segment 68 a having a left hand flight 70 and a second segment 68 b having a right hand flight 72. The end of the first segment 68 a is axially adjacent to the end of the second segment 68 b at a convergence area 74 (also identified by a triangle in the figures) such that rotation of the squeegee element 62 moves liquid along the first and second segments 68 a, 68 b on the surface in opposed axial directions toward the convergence area 74. More specifically, with the forward rotation direction of the rotary squeegee 58, the left hand flights 70 cause the fluid on the surface 18 to flow toward the convergence area 74 and the right hand flights 72 cause the fluid on the surface 18 to flow toward the convergence area 74. The helical shape of the squeegee element 62 moves the fluid on the surface 18 in an axial direction as the squeegee element 62 rotates. The surface cleaning head 14 will move in the forward or reverse direction as the squeegee element 62 is rotating and therefore the movement of the fluid will not be purely axial but will likely also have some forward or rearward component of movement as well.
The convergence area 74 is aligned with the suction inlet 28 such that the rotating rotary squeegee 58 moves the liquid on the floor toward the convergence area 74 and better positioned for suction into the suction inlet 28 for recovery of the liquid from the surface 18. Directing fluid to a convergence area 74 aligned with the suction inlet 28 enables improved collection of fluid drawn by the suction source into the suction inlet 28. In some embodiments, the improvement can be utilized by lowering the power of the suction source. This may be advantageous for battery-operated cleaners by providing a longer duration of operation for a battery capacity.
As best illustrated in FIG. 7, the first segment 68 a includes five continuous squeegee elements 62 equally angularly spaced from each other around the circumference of the body 60 and the second segment 68 b includes five continuous squeegee elements 62 equally angularly spaced from each other around the circumference of the body 60. The squeegee elements 62 slant away from the direction of rotation by a rake angle 76 between 2 and 60 degrees, more particularly between 20 and 50 degrees, and even more particularly between 35 and 50 degrees. In some embodiments, the squeegee elements 62 have no rake angle 76 and instead extend radially from the body 60.
The pitch of each of the squeegee elements 62 is measured as the distance in the axial direction traveled between two common points on the helical squeegee element 62. For example, if the rotary squeegee 58 is not moving, this would be the distance between a first point the squeegee element 62 contacts the surface 18 to a second closest point on the squeegee element 62 that also contacts the surface 18 (or to a hypothetical point that would contact the surface 18 on a hypothetical extension of the helical squeegee element 62). Pitch may vary as desired based on the size of the rotary working element 32 and the distance of desired axial fluid travel. The pitch may be 2 times the distance of the segment 68 of the rotary squeegee 58, it may be between 0.5 to 4 times the distance of the segment 68, or it may be between 0.8 and 2.5 times the distance of the segment 68.
Referring again to FIG. 7, the squeegee elements 62 are positioned to engage the surface 18 to perform the wiping function. The squeegee elements 62 may engage the surface 18 by between 0.2 and 5 mm engagement as desired to provide desired wiping performance in the application. A larger rake angle 76 may enable a larger amount of surface engagement and smaller rake angles 76 may require less surface engagement. For one embodiment, the rake angle 76 is between 35 and 50 degrees and the amount of interference with the floor is between 1 and 4 mm.
FIGS. 8 and 9 illustrate another embodiment of a rotary squeegee 158. The rotary squeegee 158 is similar to the rotary squeegee 58 shown in FIGS. 5-7 except that the squeegee elements 162 in each of the first and second segments 168 a, 168 b do not include squeegee elements 162 forming continuous helixes. Rather, the squeegee elements 162 are discontinuous. The first segment 168 a is formed by a plurality of helical left hand squeegee elements 162 in series axially adjacent and angularly offset from each other forming gaps 178 in the plurality of squeegee elements 162. The second segment 168 b is formed by a plurality of helical right hand squeegee elements 162 in series axially adjacent and angularly offset from each other forming gaps 178 in the plurality of squeegee elements 162. In particular, the gaps 178 are arranged in the discontinuous squeegee elements 162 such that they align with the gap 178 of the adjacent squeegee element 162 to form a helical pattern.
The first segment 168 a includes three discontinuous squeegee elements 162 relatively equally angularly spaced from each other around the circumference of the body 160 and the second segment 168 b includes three discontinuous squeegee elements 162 relatively equally angularly spaced from each other around the circumference of the body 160. Other embodiments of the rotary squeegee 158 can include 1, 2, 4, or more than 5 squeegee elements 162 helically wound about the axis 136 and equally or unequally spaced around the circumference of the body 160.
FIGS. 10 and 11 illustrate another embodiment of a rotary squeegee 258 similar to the rotary squeegee 158 shown in FIGS. 8 and 9 in that the rotary squeegee 258 includes two segments 268 a, 268 b, a single convergence area 274 centrally located on the rotary squeegee 258, and three angularly-spaced discontinuous squeegee elements 262 on both the first and second segments 268 a, 268 b. The rotary squeegee 258 of FIGS. 10 and 11 is different from the one shown in FIGS. 8 and 9 in that arrangement of the gaps 278 is different.
FIGS. 12-14 illustrate another embodiment of the rotary squeegee 358 similar to the rotary squeegee 58 shown in FIGS. 5-7 except that the each segment 368 includes only three squeegee elements 362 wound around the axis 336 and angularly spaced from each other. The squeegee elements 362 also include a shorter pitch and a smaller rake angle 376 than the squeegee elements 62 shown in FIGS. 5-7.
FIG. 15 illustrates additional embodiments of the working element chamber 426 and the rotary squeegee 458. In this embodiment, the working element chamber 426 includes two spaced apart suction inlets 428 a, 428 b aligned with two spaced apart convergence areas 474 a, 474 b on the rotary squeegee 458.
As shown in FIGS. 16 and 17, the squeegee elements 462 are divided into a first segment 468 a having a left hand flight, a second segment 468 b having a right hand flight, a third segment 468 c having a left hand flight, and a fourth segment 468 d having a right hand flight. The end of the first segment 468 a is axially adjacent to the end of the second segment 468 b at a first convergence area 474 a such that rotation of the squeegee element 462 moves liquid along the first and second segments 468 a, 468 b on the surface 418 in opposed axial directions toward the first convergence area 474 a. The end of the third segment 468 c is axially adjacent to the end of the fourth segment 468 d at a second convergence area 474 b such that rotation of the squeegee element 462 moves liquid along the third and fourth segments 468 c, 468 d on the surface 418 in opposed axial directions toward the second convergence area 474 b.
More specifically, with the forward rotation direction of the rotary squeegee 458, the left hand flights cause the fluid on the surface to flow from right to left (as shown in FIG. 17) toward the first and second convergence areas 474 a, 474 b and the right hand flights cause the fluid on the surface to flow from left to right toward the first and second convergence areas 474 a, 474 b. The adjacent ends of the second and third segments 468 b, 468 c does not define a convergence area 474, but instead defines a divergence area 480 as the adjacent segments 468 b, 468 c will act to split the fluid and move it in opposite outward directions toward the first and second convergence areas 474 a, 474 b.
The first and second convergence areas 474 a, 474 b are aligned with the first and second suction inlets 428 a, 428 b such that the rotating rotary squeegee 458 moves the liquid on the surface 418 toward the convergence areas 474 a, 474 b for suction into the suction inlets 428 a, 428 b thus removing the liquid from the surface 418. Directing fluid to the two convergence areas 474 a, 474 b aligned with the suction inlets 428 a, 428 b enables improved collection of fluid drawn by the suction source into the suction inlets 428 a, 428 b. In some embodiments, the improvement can be utilized by lowering the power of the suction source. This may be advantageous for battery-operated cleaners by providing a longer duration of operation for a battery capacity.
FIGS. 18-20 illustrate another embodiment of a rotary squeegee 558 to be utilized with a working element chamber 526 having two suction or more inlets 528 a, 528 b. The rotary squeegee 558 includes four convergence areas 574 a, 574 b, 574 c, 574 d defined by adjacent segments 568 of squeegee elements 562 having opposed flights. As opposed to previously described embodiments, the convergence areas 574 a, 574 b, 574 c, 574 d do not align with the suction inlets 528 a, 528 b. Instead, the divergence areas 580 a, 580 c located between the two pairs of outer convergence areas 574 a, 574 b and 574 c, 574 d align with the first and second suction inlets 528 a, 528 b. The squeegee elements 562 of adjacent segments 568 may overlap partially in the axial direction.
Other embodiments of the rotary squeegee may include 3 or more than four convergence areas. In addition, any number of convergence areas can be used with any number of suction inlets. In addition, the convergence areas may or may not be aligned with the suction inlets.
FIGS. 21-22 illustrate another embodiment of the rotary working element 632 including a plurality of uniformly distributed nubs 682 extending radially from the body 660 toward the surface 618 to be cleaned. Alternatively, the nubs 682 could be arranged in a helical pattern, a chevron pattern, or an otherwise non-uniformly distributed pattern. The nubs 682 may be positioned in any spacing or arrangement as desired for the application.
The nubs 682 are cylindrical or tapered cylindrical having a diameter between 1 mm and 5 mm, and more specifically between 2 mm and 4 mm. In one embodiment, the length of the nubs 682 is between 5 and 20 mm in length extending from the body 660, and more particularly between 6 and 15 mm in length. In yet another embodiment, the nubs 682 are between 8 mm and 12 mm in length having a diameter between 1.5 and 3.5 mm.
Each of the nubs 682 is spaced from adjacent nubs 682 by a center-to-center distance between 1.3 times the diameter to 6 times the diameter and may be spaced apart as desired for various applications. In the illustrated embodiment, the nubs are spaced a center-to-center distance of between 1.5 times and 2.5 times the diameter of the nubs 682 in a first helical direction and spaced a center-to-center distance of between 2.5 times and 4 times the diameter of the nubs in a second direction orthogonal to the first direction.
The nubs 682 are positioned to engage the surface 618 to perform an agitating and wiping function. The nubs 682 may engage the surface 618 by between 0.2 mm and 5 mm engagement as desired to provide desired wiping performance. The nubs 682 are aligned radially from the body 660, but could alternatively slant away from the direction of rotation by a rake angle. A larger rake angle may enable a larger amount of surface engagement and smaller rake angles may require less surface engagement. In some embodiments, the rake angle is between 2 and 60 degrees, more particularly between 20 and 50 degrees, and even more particularly between 35-50 degrees. For one embodiment, the rake angle is between 35 and 50 degrees and the amount of interference with the floor is between 2 mm and 4 mm.
FIGS. 23 and 24 illustrate another embodiment of a rotary working element 732 including the combination of a rotary squeegee 758 similar to the rotary squeegee 58 illustrated in FIGS. 4-6 and a plurality of nubs 782 distributed uniformly between the plurality of squeegee elements 762 of the rotary squeegee 758. In other embodiments, the rotary working element can include any other helical squeegee embodiment illustrated or disclosed and include a plurality of nubs distributed uniformly between the plurality of squeegee elements of the helical squeegee.
The squeegee elements 762 and the nubs 782 are made from silicone material. In one embodiment, the silicone material is a hydrophobic material. The hydrophobic silicone material has hydrophobicity measured by a contact angle in a range from 80° to 135° in one embodiment. In one embodiment, the hydrophobicity of the silicone material is measured by a contact angle greater than 135°. In yet another embodiment, the silicone material has a hydrophobicity measured by a contact angle in a range from 85° to 115°. The hydrophobic silicone helps facilitate cleaning of the squeegee. Additionally, silicone material is resistant to elevated temperatures, is flexible, and durable. In other embodiments, the features are made from natural or synthetic rubber, thermoplastic elastomer, polyurethane, or thermoplastic polyurethane, or any other flexible, resilient material as desired for the cleaning application. In one embodiment, the durometer is between 45 and 60 Shore A. In another embodiment, the durometer is between 60 and 80 Shore A.
Although not illustrated, some embodiments of the floor cleaner may include the use of two rotary working elements used in combination such that one rotary working elements is used in front of the other rotary working element relative to the forward direction of the surface cleaning head. The front and rear rotary working elements can be any combination of the illustrated or disclosed rotary working elements. The front and rear rotary working elements can be the same or different from each other.

Claims

1.-25. (canceled)

26. A floor cleaner comprising:

a suction source;

a housing including a working element chamber having an opening facing toward a surface to be cleaned and a suction inlet in fluid communication with the suction source; and

a rotary squeegee positioned within the working element chamber configured to move fluid along the surface to be cleaned, the rotary squeegee including a body rotatable about an axis and a flexible squeegee element extending outwardly from the body to contact the surface to be cleaned though the opening, the squeegee element arranged around the body in a helical pattern about the axis, wherein the pitch of the squeegee element is 0.5 to 2.5 times the axial length of the squeegee element, and wherein the squeegee element includes a base portion connected to the body and a squeegee edge configured to wipe the floor as the rotary squeegee rotates.

27. The floor cleaner of claim 26, wherein the squeegee element rotates to move fluid on the surface in an axial direction toward the suction inlet.

28. The floor cleaner of claim 26, wherein the squeegee element includes a first segment having a left hand flight and a second segment having a right hand flight, wherein an end of the first segment is axially adjacent an end of the second segment at a convergence area such that rotation of the squeegee element moves liquid along the first segment and along the second segment on the surface in axial directions toward the convergence area.

29. The floor cleaner of claim 28, wherein the convergence area is aligned with the suction inlet.

30. The floor cleaner of claim 28, wherein the first segment is formed by a continuous helical left hand squeegee element or by a plurality of helical left hand squeegee elements in series axially adjacent to each other.

31. The floor cleaner of claim 30, wherein adjacent ones of the plurality of helical left hand squeegee elements are angularly offset from each other.

32. The floor cleaner of claim 28, wherein the second segment is formed by a continuous helical right hand squeegee element or by a plurality of helical right hand squeegee elements in series axially adjacent to each other.

33. The floor cleaner of claim 32, wherein adjacent ones of the plurality of helical right hand squeegee elements are angularly offset from each other.

34. The floor cleaner of claim 28, wherein the squeegee element includes a third segment having a left hand flight and a fourth segment having a right hand flight, wherein an end of the third segment is axially adjacent an end of the fourth segment at a second convergence area such that rotation of the squeegee element moves liquid along the third segment and along the fourth segment on the surface in axial directions toward the second convergence area.

35. The floor cleaner of claim 34, wherein the convergence area is a first convergence area, wherein the suction inlet is a first suction inlet, wherein the floor cleaner further comprises a second suction inlet in fluid communication with the suction source, and wherein the first convergence area is aligned with the first suction inlet and the second convergence area is aligned with the second suction inlet.

36. The floor cleaner of claim 26, wherein the rotary squeegee includes a plurality of convergence areas, wherein each convergence area is defined by adjacent segments of the squeegee element having opposed flights.

37. The floor cleaner of claim 36, further comprising a plurality of suction inlets in fluid communication with the suction source, and wherein each of the plurality of convergence areas correspond to one of the plurality of suction inlets.

38. The floor cleaner of claim 37, wherein three convergence areas are each aligned with a corresponding one of three suction inlets.

39. The floor cleaner of claim 36, further comprising a plurality of suction inlets in fluid communication with the suction source, wherein the number of suction inlets is less than the number of convergence areas.

40. The floor cleaner of claim 26, wherein the squeegee element slants away from the direction of rotation by a rake angle between 2 and 60 degrees.

41. The floor cleaner of claim 40, wherein the rake angle is between 35 and 50 degrees, and the squeegee element engages with the floor between 2 mm and 4 mm engagement to perform the wiping function.

42. The floor cleaner of claim 26, wherein the rotary squeegee includes a plurality of squeegee elements angularly spaced apart from each other across the cross-sectional circumference of the body.

43. The floor cleaner of claim 26, wherein the pitch of the squeegee element is 0.5 to 4 times the axial length of the squeegee element.

44. The floor cleaner of claim 26, wherein the squeegee element includes a plurality of segments in series axially adjacent to each other, wherein the pitch of each one of the plurality of segments is 0.8 to 2.5 times the length of the corresponding one of the plurality of segments.

45. The floor cleaner of claim 26, wherein the squeegee element extends along a squeegee axis extending from the body, and the squeegee edge further includes a forwardly extending flange, the flange extending along a flange axis angled forwardly relative to the squeegee axis.

46. The floor cleaner of claim 26, wherein the angle between the flange axis and the squeegee axis is between 70 and 105 degrees.

47. The floor cleaner of claim 26, wherein the flange extends from the squeegee element a length of between 1 and 5 millimeters.

48. The floor cleaner of claim 26, wherein the flange extends from the squeegee element a length of between 5 and 10 millimeters.

49. The floor cleaner of claim 45, wherein the rotary squeegee includes a plurality of ribs extending between the base portion and the squeegee element.

50. The floor cleaner of claim 26, wherein the squeegee element is silicone.

51. The floor cleaner of claim 26, wherein the rotary squeegee includes a plurality of ribs extending between the base portion and the squeegee element.

52. The floor cleaner of claim 51, wherein the plurality of ribs are positioned on the rotary squeegee in the direction of rotation.

53. The floor cleaner of claim 52, wherein adjacent ribs are spaced from each other by between 5 and 20 millimeters.

54. The floor cleaner of claim 26, wherein the rotary squeegee further includes a plurality of flexible nubs extending radially from the body toward the surface to be cleaned, wherein the plurality of nubs are distributed uniformly between the helical pattern of the squeegee element.

55. The floor cleaner of claim 45, wherein the nubs are cylindrical or tapered cylindrical having a diameter between 1 mm and 5 mm.

56. The floor cleaner of claim 45, wherein each of the plurality of nubs include a diameter, and wherein the nubs are spaced from adjacent nubs by a center-to-center distance between 1.3 times the diameter to 6 times the diameter.

57. The floor cleaner of claim 45, wherein the plurality of nubs are arranged on the body in a helical arrangement.

58.-62. (canceled)