U.S. patent application number 14/702253 was filed with the patent office on 2015-11-05 for mobile floor cleaner with cleaning solution generator.
The applicant listed for this patent is Tennant Company. Invention is credited to David W. Augustine, Mark S. Citsay, H. Chris Killingstad.
Application Number | 20150313435 14/702253 |
Document ID | / |
Family ID | 53180850 |
Filed Date | 2015-11-05 |
United States Patent
Application |
20150313435 |
Kind Code |
A1 |
Citsay; Mark S. ; et
al. |
November 5, 2015 |
MOBILE FLOOR CLEANER WITH CLEANING SOLUTION GENERATOR
Abstract
A mobile floor cleaner that includes a moveable housing, a
cleaning head operably supported by the moveable housing, one or
more solution generators configured to receive a feed liquid and to
generate a cleaning solution from the feed liquid by application of
acoustic energy and/or nanobubble generation, and control
electronics configured to operate the one or more solution
generators.
Inventors: |
Citsay; Mark S.; (Lake Elmo,
MN) ; Killingstad; H. Chris; (Orono, MN) ;
Augustine; David W.; (Chanhassen, MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Tennant Company |
Minneapolis |
MN |
US |
|
|
Family ID: |
53180850 |
Appl. No.: |
14/702253 |
Filed: |
May 1, 2015 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
61987799 |
May 2, 2014 |
|
|
|
62068426 |
Oct 24, 2014 |
|
|
|
Current U.S.
Class: |
134/6 ;
15/50.1 |
Current CPC
Class: |
A47L 11/4083 20130101;
A47L 11/283 20130101; A47L 11/34 20130101; A47L 11/4038 20130101;
A47L 11/405 20130101 |
International
Class: |
A47L 11/283 20060101
A47L011/283; A47L 11/40 20060101 A47L011/40; A47L 11/34 20060101
A47L011/34 |
Claims
1. A mobile floor cleaner comprising: a moveable housing; a
cleaning head operably supported by the moveable housing; a liquid
source configured to provide a feed liquid; a conduit configured to
relay the feed liquid from the liquid source; one or more solution
generators configured to receive the feed liquid from the conduit,
and to generate a cleaning solution from the feed liquid by
application of acoustic energy and nanobubble generation; and
control electronics configured to operate the one or more solution
generators.
2. The mobile floor cleaner of claim 1, wherein at least one of the
solution generators comprises: a transducing unit configured to
apply the acoustic energy; and at least one of an electrolysis cell
configured to generate the nanobubbles by electrolysis and a
mechanical nanobubble generator configured to generate the
nanobubbles through shear forces.
3. The mobile floor cleaner of claim 2, wherein the acoustic energy
comprises ultrasonic waves.
4. The mobile floor cleaner of claim 1, wherein the cleaning head
comprises a disc-type scrubbing brush, and wherein the mobile floor
cleaner further comprises a motor configured to operably rotate the
scrubbing brush.
5. The mobile floor cleaner of claim 4, wherein the one or more
solution generators are secured to the cleaning head.
6. The mobile floor cleaner of claim 5, wherein the cleaning head
further comprises a cover for the scrubbing brush, and wherein the
one or more solution generators comprise a plurality of solution
generators secured to the cover of the cleaning head.
7. The mobile floor cleaner of claim 5, wherein the one or more
solution generators are secured to the cleaning head as one or more
radial rows.
8. The mobile floor cleaner of claim 1, wherein the one or more
solution generators are arranged at a location that is in front of
the cleaning head in a primary direction of movement of the mobile
floor cleaner.
9. The mobile floor cleaner of claim 8, wherein the one or more
solution generators comprise a plurality of the solution generators
arranged in a row.
10. The mobile floor cleaner of claim 1, wherein the cleaning head
comprises a rotatable cylindrical member having a compressible
outer surface, and wherein the one or more solution generators are
located inside of the rotatable cylindrical member.
11. A method for cleaning a surface, the method comprising:
providing a mobile floor cleaner having a cleaning head and a
solution generator; directing a flow of a feed liquid to the
solution generator; generating a cleaning solution by applying
acoustic energy to and generating nanobubbles in the feed liquid in
the solution generator; dispensing the generated cleaning solution
to the surface; and agitating the dispensed cleaning solution with
the cleaning head.
12. The method of claim 11, wherein applying the acoustic energy is
performed prior to generating the nanobubbles.
13. The method of claim 11, wherein generating the nanobubbles is
performed prior to applying the acoustic energy.
14. The method of claim 11, wherein applying the acoustic energy to
the feed liquid comprises inducing ultrasonic waves through the
feed liquid.
15. The method of claim 11, wherein generating the nanobubbles in
the feed liquid comprises conducting electrolysis on the feed
liquid.
16. A mobile floor cleaner comprising: a moveable housing; a liquid
source configured to provide a feed liquid; a conduit configured to
relay the feed liquid from the liquid source; a scrubbing brush
operably supported by the moveable housing, wherein the scrubbing
brush comprises: a backing portion; one or more sub-units each
configured to retain a set of bristles; and one or more transducers
supported by the backing portion and configured to vibrate the one
or more sub-units and retained sets of bristles; and control
electronics configured to operate the one or more transducers.
17. The mobile floor cleaner of claim 16, further comprising one or
more solution generators configured to receive the feed liquid from
the conduit, and to generate a cleaning solution from the feed
liquid by application of acoustic energy and nanobubble
generation.
18. The mobile floor cleaner of claim 16, further comprising a
motor configured to rotate the scrubbing brush.
19. The mobile floor cleaner of claim 18, further comprising one or
more solution generators configured to receive the feed liquid from
the conduit, and to generate a cleaning solution from the feed
liquid by application of acoustic energy and nanobubble
generation.
20. The mobile floor cleaner of claim 16, wherein the one or more
transducers are configured to vibrate the one or more sub-units and
retained sets of bristles at an ultrasonic frequency.
Description
CROSS-REFERENCE
[0001] This application claims priority to U.S. Provisional Patent
Application No. 61/987,799, filed May 2, 2014, and U.S. Provisional
Patent Application No. 62/068,426, filed Oct. 24, 2014. The entire
contents of these applications are incorporated herein by
reference.
FIELD
[0002] The present disclosure relates to cleaning machines, such as
mobile floor cleaners. In particular, the present disclosure
relates to mobile floor cleaners that incorporate acoustic energy
and/or nanobubble generation.
BACKGROUND
[0003] Floor cleaning in public, commercial, institutional and
industrial buildings have led to the development of various
specialized floor cleaning machines, such as hard and soft floor
cleaning machines. These cleaning machines generally utilize a
cleaning liquid dispensing system and a cleaning head to perform a
floor cleaning operation.
[0004] The cleaning liquid dispensing system generally dispenses a
cleaning liquid that includes water and a chemically based
detergent. The detergent typically includes a solvent, a builder,
and a surfactant. The cleaning head typically includes one or more
disc-type scrubbing brushes, which may be located in front of,
under or behind the floor cleaning machine. The scrubbing brushes
typically include nylon bristles, pads or other fibers. The
scrubbing brushes are motorized to rotate during cleaning
operations. The rotation of the scrubbing brushes causes the
brushes to scrub the surface being cleaned as they engage the
surface.
[0005] While detergents increase cleaning effectiveness for a
variety of different soil types, such as dirt and oils, these
detergents also have a tendency to leave unwanted residue on the
cleaned surface. Such residue can adversely affect the appearance
of the surface and the tendency of the surface to re-soil.
Additionally, the detergents may not be environmentally friendly.
Some mobile floor cleaning machines have been fitted with
electrolysis cells for producing an electrochemically-activated
cleaning liquid by electrolyzing a feed liquid such as tap
water.
[0006] Improved floor cleaning heads, mobile floor cleaners, and
floor cleaning methods are desired for reducing the use of
detergents during cleaning operations, while maintaining the
efficacy of the floor cleaning operation.
SUMMARY
[0007] An aspect of the present disclosure is directed to a mobile
floor cleaner that includes a moveable housing, a cleaning head
operably supported by the moveable housing, a liquid source
configured to provide a feed liquid, and a conduit configured to
relay the feed liquid from the liquid source. The mobile floor
cleaner also includes one or more solution generators configured to
receive the feed liquid from the conduit, and to generate a
cleaning solution from the feed liquid by application of acoustic
energy (e.g., via ultrasonic waves) and nanobubble generation
(e.g., via electrolysis). The mobile floor cleaner further includes
control electronics configured to operate the one or more solution
generators.
[0008] Another aspect of the present disclosure is directed to a
method for cleaning a surface. The method includes providing a
mobile floor cleaner having a cleaning head and a solution
generator, directing a flow of a feed liquid to the solution
generator, and generating a cleaning solution by applying acoustic
energy to and generating nanobubbles in the feed liquid in the
solution generator. The method also includes dispensing the
generated cleaning solution to the surface, and agitating the
dispensed cleaning solution with the cleaning head.
[0009] Another aspect of the present disclosure is directed to a
mobile floor cleaner that includes a moveable housing, a liquid
source configured to provide a feed liquid, a conduit configured to
relay the feed liquid from the liquid source, and a scrubbing brush
operably supported by the moveable housing. The scrubbing brush
includes a backing portion, one or more sub-units each configured
to retain a set of bristles, and one or more transducers supported
by the backing portion and configured to vibrate the one or more
sub-units and retained sets of bristles. The mobile floor cleaner
also includes control electronics configured to operate the one or
more transducers.
DEFINITIONS
[0010] Unless otherwise specified, the following terms as used
herein have the meanings provided below:
[0011] The terms "preferred" and "preferably" refer to embodiments
of the invention that may afford certain benefits, under certain
circumstances. However, other embodiments may also be preferred,
under the same or other circumstances. Furthermore, the recitation
of one or more preferred embodiments does not imply that other
embodiments are not useful, and is not intended to exclude other
embodiments from the scope of the present disclosure.
[0012] The term "providing", such as for "providing a mobile floor
cleaner", when recited in the claims, is not intended to require
any particular delivery or receipt of the provided item. Rather,
the term "providing" is merely used to recite items that will be
referred to in subsequent elements of the claim(s), for purposes of
clarity and ease of readability.
[0013] The terms "about" and "substantially" are used herein with
respect to measurable values and ranges due to expected variations
known to those skilled in the art (e.g., limitations and
variabilities in measurements).
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a side schematic illustration of an example mobile
floor cleaner of the present disclosure.
[0015] FIG. 2 is a top perspective view of a cleaning head of the
mobile floor cleaner.
[0016] FIG. 3 is an exploded top perspective view of a scrubbing
brush of the cleaning head shown in FIG. 2.
[0017] FIG. 4 is a side schematic illustration of the scrubbing
brush with a solution generator having a transducer unit located
upstream from an electrolysis cell.
[0018] FIG. 5A is a side schematic illustration of the scrubbing
brush with an alternative solution generator having an electrolysis
cell located upstream from a transducer unit.
[0019] FIG. 5B is a side schematic illustration of the example
mobile floor cleaner of FIG. 1 showing an alternative solution
generator configuration.
[0020] FIG. 6 is a top schematic illustration of an alternative
scrubbing brush of the cleaning head, which includes radial rows of
multiple solution generators.
[0021] FIG. 7 is a side schematic illustration of the alternative
scrubbing brush shown in FIG. 6.
[0022] FIG. 8 is a side schematic illustration of an alternative
cleaning head having multiple front-located solution
generators.
[0023] FIG. 9 is a top schematic illustration of the alternative
cleaning head shown in FIG. 8.
[0024] FIG. 10 is a top schematic illustration of an alternative
scrubbing brush having bristles secured to multiple transducer
sub-units.
[0025] FIG. 11 is a side schematic illustration of the alternative
scrubbing brush shown in FIG. 10.
[0026] FIG. 12 is a side schematic illustration of a second example
mobile floor cleaner of the present disclosure having multiple
solution generators separate from the cleaning head.
[0027] FIG. 13 is a schematic illustration of a third example
mobile floor cleaner of the present disclosure having multiple
solution generators separate from a dual-roller cleaning head.
[0028] FIG. 14 is a front perspective view of an alternative
cleaning head having a cylindrical member.
[0029] FIG. 15 is an exploded perspective view of the alternative
cleaning head shown in FIG. 14.
[0030] FIG. 16 is an illustration of an example portable cleaning
stick that includes a solution generator for applying localized
cleaning fluid.
DETAILED DESCRIPTION
[0031] The present disclosure is directed to a mobile floor cleaner
that includes an acoustic transducer (e.g., an ultrasonic
transducer) and/or a nanobubble generator (e.g., with an
electrolysis cell or other nanobubble generator), which produce a
cleaning solution from an aqueous feed liquid, such as water. As
discussed below, the acoustic transducer and/or the nanobubble
generator, in combination with a floor cleaning head, allows the
mobile floor cleaner to clean floor surfaces effectively with
little or no additives (e.g., detergents), and preferably with low
power consumption. The lower power consumption correspondingly
allows the mobile floor cleaner to incorporate smaller and/or fewer
batteries with sustainable operating durations.
[0032] FIG. 1 illustrates an example mobile floor cleaner 10 of the
present disclosure, which may be designed for use by an operator
that walks behind the machine or rides on the machine. Examples of
suitable cleaning units for mobile floor cleaner 10 include the
"T"-series scrubbers from Tennant Company, Minneapolis, Minn.,
which are modified to operate as discussed below. Alternatively,
mobile floor cleaner 10 may be configured to be towed behind
another vehicle.
[0033] As shown, mobile floor cleaner 10 includes housing 12, which
is supported by wheels 14 that advance mobile floor cleaner 10 in
the direction of arrow 16 along a surface to be cleaned, such as
surface 18. One or more of wheels 14 are correspondingly rotated by
motor 20 based on operator commands, where motor 20 may include one
or more electric motors and/or an internal combustion engine. Motor
20 may also be configured to rotate wheels 14 in the opposing
directions to reverse the movement of mobile floor cleaner 10.
[0034] As further shown, mobile floor cleaner 10 also includes
cleaning head 22, which, in the shown example, is a disc-type,
scrubbing brush head that includes cover or shroud 24 and rotatable
scrubbing brush 26. Scrubbing brush 26 is rotated about an axis of
rotation 28 relative to cover 24 by motor 30. Motor 30 may include
one or more electric motors that generate rotational power for a
drive shaft or other mechanism (not shown) that extends along axis
28. Preferably, axis 28 is substantially perpendicular to the
surface 18 being cleaned, allowing scrubbing brush 26 to rotate
parallel to the surface 18 being cleaned.
[0035] Mobile floor cleaner 10 also includes control electronics
32, which include one or more control circuits configured to
monitor and operate the components of mobile floor cleaner 10 over
one or more control lines (e.g., electrical, optical, and/or
wireless lines, not shown). Control electronics 32 and the
components of mobile floor cleaner 10 are preferably powered from
batteries 34, which are one or more rechargeable batteries,
allowing mobile floor cleaner 10 to move freely without requiring a
physical connection to a fixed electrical outlet. Accordingly,
control electronics 32 may direct the operation of motors 20 and 30
respectively over control lines 36 and 38.
[0036] One or more of the control functions performed by control
electronics 32 can be implemented in hardware, software, firmware,
or a combination thereof. Such software, firmware, and the like may
be stored on a non-transitory computer-readable medium, such as a
memory device. Any computer-readable memory device can be used,
such as a disc drive, a solid state drive, CD-ROM, DVD, flash
memory, RAM, ROM, a set of registers on an integrated circuit,
and/or the like. For example, the control circuit can be
implemented partly or completely in a programmable logic controller
and/or a processing device such as a microcontroller and/or other
processor that executes instructions stored in a memory device,
where the instructions configure the processor to perform the steps
of the control process when executed by the processor to convert
the processor into a special purpose computer.
[0037] Mobile floor cleaner 10 also includes liquid source 40,
which is one or more reservoirs or tanks for storing a feed liquid
42 for cleaning, and/or may include a fitting or other inlet for
receiving feed liquid 42 from an external source (e.g., from an
external hose). Feed liquid 42 is an aqueous liquid, preferably
regular, untreated tap water or other water that is commonly
available. In some embodiments, feed liquid 42 may include one or
more electrolytes to assist in an electrolysis reaction.
[0038] In some alternative situations, feed liquid 42 may also
include one or more additives, such as detergents, which preferably
do not leave post-cleaning residues and do not chemically attack
the cleaned surface 18. However, as indicated above, in preferred
embodiments, feed liquid 42 is substantially free of any
residue-forming additives, such as detergents.
[0039] Feed liquid 42 may exit liquid source 40 by conduit 44,
which may include one or more actuatable valves (e.g., valve 46)
and/or pumps (e.g., pump 48) for supplying feed liquid 42 to
cleaning head 22. Control electronics 32 may direct the operation
of valve 46 and/or pump 48 respectively over control lines 50 and
52. In alternative embodiments, feed liquid 42 may be supplied from
liquid source 40 by the operation of gravity, without pump 48.
[0040] Conduit 44 directs feed liquid 42 to solution generator 54,
which, in the shown embodiment, includes transducer unit 56 and
nanobubble generator (e.g., electrolysis cell) 58. As discussed
below, transducer unit 56 includes one or more acoustic transducers
configured to generate high-frequency acoustic waves through the
received feed liquid 42. The acoustic transducers may be any
suitable transducer, such as piezoelectric transducers and/or
magnetostrictive transducers, and preferably generate ultrasound
waves (e.g., from about 20 kilohertz to about 400 kilohertz).
[0041] The generated acoustic waves create compression waves in the
received feed liquid 42 that flows through transducer unit 56,
which produce microscopic voids or bubbles. Feed liquid 42
preferably fills the volume of transducer unit 56 at all times
during operation to prevent the formation of air pockets that can
otherwise potentially disrupt the acoustic waves.
[0042] After passing through transducer unit 56, the resulting
liquid flows through nanobubble generator 58. Nanobubble generator
58 can be implemented as an electrolysis cell that generates
nanobubbles in the flowing liquid through electrolysis. Examples of
suitable cells for an electrolysis cell nanobubble generator 58
include those disclosed in U.S. Pat. No. 8,156,608. In alternative
embodiments, nanobubble generator 58 may be replaced with other
nanobubble generators, such as mechanical nanobubble generators
(e.g., air infiltration sieves, venturi nozzles, swirl nozzles).
These nanobubble generators can generate nanobubbles through shear
forces without application of electrical energy. Therefore,
although various example configurations described herein are
described as having an electrolysis cell 58, the configurations may
be implemented using a mechanical nanobubble generator in addition
to or in lieu of electrolysis cell 58 without departing from the
scope of the disclosure.
[0043] The flowing liquid received from transducer unit 56 also
preferably fills the volume of electrolysis cell 58 at all times
during operation to maintain the electrolysis reaction.
Accordingly, transducer unit 56 and electrolysis cell 58 are each
preferably sized based on the volumetric flow rate of feed liquid
42 to solution generator 54, which is accordingly dependent on the
dimensions of conduit 44 and operational rate of pump 48.
[0044] The resulting cleaning solution that is generated may then
exit electrolysis cell 58 (or other nanobubble generator) via a
dispensing nozzle or orifice 60. The dispensed cleaning solution
preferably provides a suitable path for conducting the acoustic
waves (e.g., ultrasonic waves) from transducer unit 56 to the
surface 18 being cleaned, through the dispensed cleaning solution.
The dispensed cleaning solution also preferably carries the
entrained nanobubbles to the surface 18 being cleaned.
[0045] Control electronics 32 may direct the operation of solution
generator 54 (i.e., transducer unit 56 and electrolysis cell 58)
over control line 62. In the shown embodiment, solution generator
54 is retained by scrubbing brush 26 of cleaning head 22 at its
axial location. While not wishing to be bound by theory, it is
believed that having the flow of the cleaning solution traverse
around conduit corners or other conduit bends can adversely affect
the stability of the generated cleaning solution, which can
potentially reduce its cleaning efficiency. Therefore, solution
generator 54 is preferably located close to and directed towards
the surface being cleaned (e.g., surface 18) to preserve the
cleaning effectiveness. This is believed to provide a suitable path
for conducting the acoustic waves (e.g., ultrasonic waves) and for
carrying the entrained nanobubbles from solution generator 54 to
the surface 18 being cleaned, through the dispensed cleaning
solution.
[0046] The arrangement shown in FIG. 1, with solution generator 54
at the axial location of scrubbing brush 26, provides a suitable
arrangement for dispensing the cleaning solution directly onto
surface 18, and then agitating the cleaning solution with the
rotating scrubbing brush 26 after the initial dispensing. This is
believed to allow the generated bubbles from transducer unit 56 and
electrolysis cell 58 to attract to and/or dislodge the contaminants
(e.g., dirt) on surface 18 prior to being agitated with the
rotating bristles of scrubbing brush 26. The rotating bristles may
then abrasively remove the contaminants along with the cleaning
solution to clean surface 18.
[0047] As discussed below, solution generator 54 may rotate with
scrubbing brush 26 while scrubbing brush 26 is driven by motor 30.
As such, solution generator 54 may be a sacrificial unit that is
permanently attached to the scrubbing brush 26, and the elements of
transducer unit 56 and electrolysis cell 58 may be integrated
within scrubbing brush 26 such that the brush and solution
generator 54 are fabricated together as a single, unitary part.
Alternatively, solution generator 54 may be fabricated as separate
components that are secured to scrubbing brush 26.
[0048] Mobile floor cleaner 10 may also include a recovery system
64, which, in the shown embodiment, includes one or more vacuum
units 66, one or more vacuum extractor tools 68, one or more vacuum
squeegees 70, a vacuum path selector 72, and one or more waste
recovery tanks 74. Vacuum unit 66 is used in combination with
vacuum extractor tool 68 and/or vacuum squeegee 70 to remove liquid
and solid waste (i.e., soiled cleaning liquid) from surface 18.
Control electronics 32 may direct operation of vacuum unit 66 over
control line 75.
[0049] Vacuum extractor tool 68 may be used for removing liquid and
solid debris from soft surfaces 18, whereas vacuum squeegee 70 may
be used for removing liquid and solid debris from hard surfaces 18,
for example. Other types of liquid and debris recovery tools and
methods can also be used for use on hard surfaces, soft floor
surfaces, or both. Mobile floor cleaner 10 may also include one or
more lift mechanisms (not shown) operated by control electronics 32
to independently raise and lower vacuum extractor tool 68 and
vacuum squeegee 70.
[0050] The waste is passed through vacuum path selector 72 and into
waste recovery tank 74. Vacuum path selector 72 allows a single
vacuum unit 66 to selectively couple to vacuum extractor tool 68
and vacuum squeegee 70. Alternatively, separate vacuum units 66 may
be individually used for vacuum extractor tool 68 and vacuum
squeegee 70. In this alternative embodiment, vacuum path selector
72 may be optionally omitted.
[0051] During a cleaning operation, control electronics 32 may
energize motor 30 (via control line 38) to rotate scrubbing brush
26 about axis 28, open valve 46 (via control line 50), and energize
pump 48 (via control line 52) to supply the feed liquid 42 through
conduit 44 to solution generator 54. Control electronics 32 may
also energize the acoustic transducers in transducer unit 56 to
generate acoustic waves (e.g., ultrasonic waves) through the feed
liquid 42 flowing through transducer unit 56.
[0052] Control electronics 32 may also energize electrolysis cell
58 to generate nanobubbles in the liquid that passes through the
cell 58 via electrolysis. In particular, control electronics 32 may
energize electrolysis cell 58 by applying a suitable voltage across
the electrodes contained in the cell. Electrolysis cell 58
accordingly generates an electrolyzed cleaning liquid that is
dispensed directly onto surface 18 at an axially-central location
along axis 28 (via dispensing nozzle 60). The electrically-charged
nanobubbles of the resulting cleaning solution then attract and
dislodge contaminants from surface 18, allowing the contaminants to
then be abrasively removed by the rotation of scrubbing brush 26.
The resulting soiled solution with the contaminants may then be
collected with recovery system 64.
[0053] While not wishing to be bound by theory, it is believed that
the combination of the acoustic energy (via transducer unit 56)
with the generated nanobubbles at electrolysis cell 58 (or other
nanobubble generator) generate a cleaning solution that is
effective for attracting and dislodging contaminants from surfaces
(e.g., surface 18). Additionally, transducer unit 56 and
electrolysis cell 58 are each low power-consuming devices. As such,
solution generator 54 is suitable for generating cleaning solutions
(free of detergents) without consuming substantial amounts of
electrical power. This accordingly preserves the operating duration
of mobile floor cleaner 10 and/or allows smaller or fewer batteries
34 to be used.
[0054] In addition, although the combination of acoustic energy and
nanobubbles generated at electrolysis cell 58 can be used to
provide an efficacious cleaning solution, it should be appreciated
that mobile floor cleaner 10 can be configured to clean using
acoustic energy without generated nanobubbles or generated
nanobubbles without acoustic energy. Depending on the application,
the cleaning efficacy provided by the acoustic energy enhancement
or nanobubbles enhancement of feed liquid 42 alone may be
sufficient to adequately clean a desired surface (e.g., surface
18). Therefore, although mobile floor cleaner 10 in the example of
FIG. 1 is described as using the combination of the acoustic energy
(via transducer unit 56) with the generated nanobubbles at
electrolysis cell 58, it should be appreciated that the disclosure
is not limited to this combination of features.
[0055] In practice, it is believed that dispensing the generated
cleaning solution directly onto surface 18 without initially
flowing into the rotating bristles of scrubbing brush 26 preserves
the cleaning effectiveness of the generated cleaning solution for
attracting and dislodging contaminants from surface 18. Shortly
after being dispensed onto surface 18, scrubbing brush 26 may then
further assist in the cleaning efforts through mechanical abrasion.
This results in a clean surface 18 that is substantially free of
film-forming residues.
[0056] FIG. 2 illustrates an example embodiment for cleaning head
22 with the integrated solution generator 54, and where cleaning
head 22 is configured to carry a single, disc-type scrubbing brush
26. As shown, cover 24 is attached to a stationary part of motor
30. Cover 24 has a substantially closed upper surface 76, and a
substantially open lower surface 78 facing the surface 18 to be
cleaned. Scrubbing brush 26 is carried underneath cover 24 and is
connected to a drive shaft or other mechanism (not shown) of motor
30, which extends through an aperture 80 at the axial center of
upper surface 76.
[0057] In addition, cleaning head 14 includes conduit 82 having a
first end configured to be connected to conduit 44 (shown in FIG.
1) for receiving feed liquid 42 from liquid source 40. A second end
of conduit 82 passes through the aperture 80 to deliver feed liquid
42 to solution generator 54 (not shown in FIG. 2) incorporated into
scrubbing brush 26. Cover 24 further includes an electrical
terminal block 84, which provides an electrical connection to
control line 62 (shown in FIG. 1) for operating solution generator
54. As explained in further detail below, cover 24 also provides a
connection from terminal block 84 to corresponding electrical
conductors on scrubbing brush 26.
[0058] FIG. 3 illustrates scrubber brush 26, which includes adapter
86 (also known as a disc hub or receiver), which attaches scrubbing
brush 26 to the drive shaft of motor 30. Adapter 86 includes a
central, female hub coupling 88, which is configured to receive and
fixedly connect to the drive shaft of motor 30. Adapter 86 may be
connected to the drive shaft by a bolt passing axially through the
coupling 88 or a set screw within coupling 88, for example. Other
methods of attachment may also be used.
[0059] Adapter 86 further includes a plurality of slots 90
configured to receive corresponding studs or cleats 92 attached to
a backing portion 94 of scrubbing brush 26, by a friction fit, for
example. A retaining spring 96 may also be provided to maintain the
brush studs 92 engaged within slots 90. Studs 92 form a mechanical
connection configured to receive a rotating driving force through
adapter 86 to rotate scrubbing brush 26.
[0060] Adapter 86 also includes an annular slot 98 around coupling
88, which includes multiple reinforcing ribs. Annular slot 98
allows the received feed liquid 42 flowing from the second end of
conduit 82 to fall downward past adapter 86. This allows the feed
liquid 42 to reach solution generator 54 despite the high-speed
rotation of scrubbing brush 26 (including adapter 86).
[0061] Scrubbing brush 26 also includes a set of bristles or other
scrubbing material 100 attached to backing portion 94. Backing
portion 94 can be formed of any suitable material such as plastic,
synthetic material, wood, metal, and the like. In a particular
example, backing portion 94 is formed of a rigid plastic material
through an injection molding processes. Bristles 100 may be
attached in any suitable manner to the lower surface of backing
portion 94. In one example, bristles 100 are molded within the
material of backing portion 94. Other attachment methods may also
be used, such as adhesives or heat sealing.
[0062] Bristles 100 can be made of any suitable material such as
plastic (e.g., nylon, polyester, polypropylene), natural animal
hair (e.g. horse or hog hair), metal fibers, abrasives, and the
like. Also, bristles 100 may be generally aligned vertically as
shown in FIG. 3 or may be interconnected or layered such as in a
pad form.
[0063] Backing portion 94 also includes a central aperture 102 in
which solution generator 54 resides, below mesh plate 104, where
mesh plate 104 maybe omitted in some embodiments. During operation,
the feed liquid 42 flows through annular slot 98 and mesh plate
104, and into transducer unit 56 of solution generator 54. This
arrangement allows transmission of the feed liquid 42 into solution
generator 54 despite the high-speed rotation of scrubbing brush 26,
as mentioned above.
[0064] Backing portion 94 also includes an electrical coupling,
such as first and second electrical conductors or contacts 106 and
108, which are electrically connected to transducer unit 56 and
electrolysis cell 58. In this example, electrical conductors 106
and 108 are formed as coaxial, annular rings on backing portion 94.
These rings are engaged by corresponding electrical brushes 110
carried by the lower surface 78 of cover portion 24, and which are
connected to terminal block 84 of cover portion 24. In an
alternative embodiment, the electrical conductors 106 and 108 are
carried by cover portion 24, and the electrical brushes 110 are
carried by backing portion 94.
[0065] As scrubbing brush 26 rotates around axis 28 within cover
portion 24, the electrical brushes 110 maintain electrical contact
with electrical conductors 106 and 108. The conductors 106 and 108
and brushes 110 can be located at any radius on the upper surface
of backing portion 94, along the periphery of backing portion 94,
and/or anywhere on adapter 86, for example. In another embodiment,
the electrical connection between terminal block 86 and electrodes
106 and 108 is made by an inductive coupling, where a first member
of the coupling is attached to cover portion 24 and a second member
of the coupling is attached to adapter 86 or backing portion 94,
for example. Other types of electrical couplings may be used in
other embodiments.
[0066] As noted above, transducer unit 56 is configured to generate
high-frequency acoustic waves in feed liquid 42, such as waves
having a frequency greater than 20 kilohertz. In general,
transducer unit 56 can be implemented using any type of acoustic
wave generator that converts electrical energy into sound waves. In
one example, transducer unit 56 includes one or more piezoelectric
transducers that utilize the piezoelectric property of a material
to convert electrical pulses into mechanical vibrations. In another
example, transducer unit 56 includes one or more magnetostrictive
transducers that utilize the magnetostrictive property of a
material to convert electrical pulses into mechanical
vibrations.
[0067] FIG. 4 is an additional simplified illustration of the
engagement between solution generator 54 and scrubbing brush 26. As
shown, transducer unit 56 of solution generator 54 may be secured
within aperture 102 below mesh plate 104, where transducer unit 56
includes one or more acoustic transducers 112 for generating the
acoustic waves (e.g., ultrasonic waves) in the received feed liquid
42, as discussed above. Beneath transducer unit 56, electrolysis
cell 58 may also be secured within aperture 102, and held in place
with dispensing nozzle 60, which may function as a restraining cap
for solution generator 54.
[0068] Electrolysis cell 58 includes first and second electrodes
114 and 116, which in the example shown in FIG. 4, are arranged
parallel to and separated from one another by a suitable gap (e.g.,
with spacer 118) to electrically isolate each other. Thus,
electrodes 114 and 116 are oriented in planes that are parallel to
the face of bristles 100 that engage the surface 18 being cleaned.
In this embodiment, electrodes 114 and 116 are mesh-type
electrodes, which enable the liquid from transducer unit 56 to pass
through electrodes 114 and 116 by the force of gravity. In
alternative embodiments, electrodes 114 and 116 may each be an
annular electrode that is concentric with axis 28, allowing the
liquid from transducer unit 56 to flow between the electrodes 114
and 116.
[0069] During operation, control electronics 32 activate acoustic
transducers 112, and apply a suitable voltage potential across
electrodes 114 and 116, via control line 62, terminal block 84,
electrical brushes 110, and conductors 106 and 108. Feed liquid 42
is supplied to transducer unit 56 through conduits 44 and 82,
aperture 80, annular slot 98, and mesh plate 104.
[0070] As motor 30 rotates scrubbing brush 26 about axis 28, the
feed liquid 42 flows through transducer unit 56 and electrolysis
cell 58 to generate the cleaning solution, as discussed above. In
particular, acoustic transducers 112 preferably create ultrasonic
waves through the flowing feed liquid 42, which then flows into
electrolysis cell 58. At electrolysis cell 58, as the received
liquid passes between the electrodes 114 and 116, the applied
voltage induces an electrical current through the liquid contained
in the gap and further generates nanobubbles in the liquid.
[0071] Due to gravity, the generated cleaning solution exits
electrolysis cell 58 through dispensing nozzle 60, and is directly
dispensed onto surface 18. As further shown in FIG. 4, after
entering transducer unit 56, the feed liquid 42 preferably flows
along a straight flow path though transducer unit 56, electrolysis
cell 58, and dispensing nozzle 60, and onto surface 18. This allows
the generated cleaning solution to be dispensed with a straight and
direct flow path onto surface 18.
[0072] After being dispensed, the mechanical action of bristles 100
disperses the cleaning solution beneath brush 26 to actively clean
surface 18. In a particular example, motor 30 may rotate scrubbing
brush 26 from about 200 rotations per minute (rpm) to about 400
rpm, such as at about 300 rpm.
[0073] An exemplary technical effect of incorporating the solution
generator 54 in the scrubbing brush 26 is that the feed liquid 42
is conditioned very close to the point of use at the surface 18
being cleaned, at the very end of the liquid flow path. This limits
neutralization of the generated cleaning solution from the time at
which the liquid is conditioned by solution generator 54 to the
time at which the liquid contacts the surface 18 being cleaned.
[0074] In an alternative embodiment, transducer unit 56 may be
separate from electrolysis cell 58, where transducer unit 56 may be
retained at any suitable location upstream from scrubbing brush 26
(e.g., secured to cover 24). In this case, electrolysis cell 58 may
be retained at any suitable location downstream from transducer
unit 56, such as at scrubbing brush 26, as shown.
[0075] FIG. 5A illustrates an alternative embodiment for solution
generator 54, where nanobubble generator 58 (e.g., an electrolysis
cell) is located upstream relative to transducer unit 56. In this
embodiment, the received feed liquid 42 initially undergoes
electrolysis to generate nanobubbles in electrolysis cell 58, and
the resulting liquid is then subjected to the ultrasonic waves of
transducer unit 56 before being dispensed.
[0076] In a further embodiment, electrolysis cell 58 may be
separate from transducer unit 56, where electrolysis cell 58 may be
retained at any suitable location upstream from scrubbing brush 26.
For example, electrolysis cell may be retained at a location along
conduit 44 and/or secured to cover 24. In this case, transducer
unit 56 may be retained at any suitable location downstream from
electrolysis cell 58, such as at scrubbing brush 26, as shown.
[0077] FIG. 5B illustrates an alternative embodiment of mobile
floor cleaner 10 where like reference numbers refer to like
elements discussed above in connection with FIGS. 1-4. In the
example of FIG. 5B, mobile floor cleaner 10 includes a solution
generator 54 that has a transducer unit 56 but which does not
contain a nanobubble generator (such as electrolysis cell 58).
Transducer unit 56 is located in fluid communication with feed
liquid 42 via conduit 44. In operation, transducer unit 56 can
receive feed liquid 42 from liquid source 40 and impart acoustic
energy to the feed liquid to generate an acoustically-enhanced
liquid. For example, operating under the control of control
electronics 32, transducer unit 56 can generate acoustic waves that
are passed into feed liquid 42 flowing through solution generator
54. The acoustically-enhanced liquid generated by solution
generator 54 can then be dispensed onto a surface to be cleaned via
dispensing nozzle or orifice 60.
[0078] The acoustic energy imparted to feed liquid 42 can enhance
the cleaning efficacy of the liquid as compared to when the liquid
is not treated with acoustic energy. Acoustic waves generated by
transducer unit 56 can propagate through feed liquid 42 as
longitudinal waves that compress and decompress in the direction of
travel. The compression and decompression of the acoustic waves can
generate cavitation bubbles or void spaces within feed liquid 42.
These cavitation bubbles or void spaces, which may or may not have
a mean diameter less than 1 nanometer, can increase cleaning
efficacy by agitating feed liquid 42 and creating a scrubbing
action. For example, when the cavitation bubbles or void spaces
implode, which can occur when the acoustically-enhanced liquid
contacts a surface to be cleaned, the implosion can generate an
intense localized shockwave. The shockwave can provide a force
sufficient to overcome contaminant-to-substrate adhesion forces,
releasing contaminants and cleaning the target surface.
[0079] When solution generator 54 is configured with transducer
unit 56 but without a nanobubble generator as shown in FIG. 5B, one
or more acoustical transducers can be positioned in a number of
different ways to direct acoustic energy into feed liquid 42. For
example, the transducers can be positioned adjacent to and, in some
examples, in contact with feed liquid 42 as it flows from liquid
source 40 to dispensing nozzle or orifice 60. In such examples, the
transducers can direct acoustic energy into feed liquid 42 prior to
applying the liquid to a surface to be cleaned. Additionally or
alternatively, the transducers can be positioned to direct acoustic
energy into feed liquid 42 after the liquid has been applied to a
surface to be cleaned. In such examples, the liquid can be
discharged via dispensing nozzle or orifice 60 onto a surface to be
cleaned and thereafter impacted with acoustic energy generated by
transducer unit 56. FIGS. 6 and 7 illustrate an alternative
embodiment for scrubbing brush 26, which includes multiple solution
generators 54 arranged radially around backing portion 94 between
groups of bristles 100. As further shown in FIG. 7, backing portion
94 may also include conduits 120 for directing the received feed
liquid 42 from aperture 102 to the individual solution generators
54 via centrifugal force and gravity.
[0080] In this embodiment, the number, sizes, and arrangements of
the multiple solution generators 54 may vary depending on the
particular cleaning requirements. As can be appreciated, due the
increased number of solution generators 54 in this embodiment, they
each may be smaller in size than the single, axially-located
solution generator shown in FIGS. 1-5. Furthermore, the number of
radial rows of the multiple solution generators 54 may vary, such
as from one row to ten rows, or from two rows to six rows, or from
three rows to five rows.
[0081] Additionally, while illustrated as liner rows of multiple
solution generators 54, each radial row may alternatively extend in
any suitable arrangement, such as with spiral arms. This embodiment
shown in FIGS. 6 and 7, and its variations, allow the generated
cleaning solution to be dispensed in situ with the rotating
bristles 100. For many applications, this can further assist in the
cleaning efficiency of mobile floor cleaner 10.
[0082] FIGS. 8 and 9 illustrate another alternative embodiment in
which multiple solution generators 54 are secured to cover 24 at a
location that is in front of scrubbing brush 26 (in the direction
of movement illustrated by arrow 16). In this embodiment, conduit
44 and control line 62 may each branch into each of the solution
generators 54 for independent or collective operation.
[0083] The number, sizes, and arrangements of the multiple solution
generators 54 in this embodiment may also vary depending on the
particular cleaning requirements. Preferably, the multiple solution
generators 54 in this embodiment produce a sufficient quantity of
the generated cleaning solution to function with the size of
scrubbing brush 26. As can be appreciated, due the increased number
of solution generators 54 in this embodiment, they each may also be
smaller in size than the single, axially-located solution generator
shown in FIGS. 1-5. Examples of suitable numbers of solution
generators 54 in this embodiment range from one to ten, or from two
to eight, or from four to six.
[0084] As shown in FIG. 9, the multiple solution generators 54 are
arranged on cover 24 of cleaning head 22 in an arced row in front
of scrubbing brush 26 (in the movement direction of arrow 16).
Alternatively, the multiple solution generators 54 may be arranged
in any suitable manner, such as a linear row, a staggered row, and
the like.
[0085] FIGS. 10 and 11 illustrate another embodiment, which may
utilized in addition to the embodiments shown in FIGS. 1-9 (as well
as in FIG. 12) and/or alternatively to the shown embodiments. As
shown in FIG. 10, scrubbing brush 26 may also include multiple
tracks, blocks, or other sub-units 122 that are supported by
backing portion 94, but are capable of vibrating relative to
backing portion 94. In particular, each sub-unit 122 is molded with
or otherwise retains a group of bristles 100, and is engaged with
one or more transducing elements 124 (e.g., as shown in FIG.
11).
[0086] The number and dimensions of sub-units 122 may be selected
to optimize the placement of bristles 100. Each sub-unit 122 is
preferably sized such that the associated transducing element(s)
124 are capable of generating sufficient vibrations. While
illustrated as rectangular tracks, each sub-unit 122 may have any
suitable geometric shape (e.g., square, round, etc. . . . ) and
size, and sub-units 122 of different shapes and sizes may be used
together to increase the covered surface area of scrubbing brush
26. Additional bristles 100 may also be molded or otherwise secured
to backing portion 94 between the sub-units 122 to increase the
brushing capabilities while rotating.
[0087] Each transducing element 124 may receive electrical power
from contacts 106 and 108, as discussed above, and is configured to
vibrate at a high frequency, such as at an ultrasonic frequency,
for example (e.g., from about 20 kilohertz to about 400 kilohertz).
This can assist in removing contaminants from surface 18 with or
without rotation. Accordingly, in some embodiments, the
high-frequency vibrations are used in combination with the rotation
of scrubbing brush 26 (via motor 30). Alternatively, the
high-frequency vibrations may be used in lieu of the rotation of
scrubbing brush 26, such as for use on delicate or fragile surfaces
18, for example.
[0088] In either case, one or more solution generators 54 may also
be used to generate the cleaning solution, as discussed above.
However, in some optional and alternative embodiments, solution
generator 54 may be omitted, and the scrubbing brush 26 with
transducing elements 124 may be used with conventional cleaning
solutions. In further embodiments, the scrubbing brush 26 with
transducing elements 124 may be used in combination with one or
more electrolysis cells 58 or other nanobubble generators (i.e.,
transducer units 56 are omitted). This arrangement allows the
scrubbing brush 26 with transducing elements 124 to be used with a
cleaning solution having entrained nanobubbles. As such, the
high-frequency vibrations of this embodiment may be used with or
without brush rotation, with or without solution generator(s) 54,
and/or with or without electrolysis cells 58 (or other nanobubble
generators). These alternative combinations increase the
versatility of mobile floor cleaner 10.
[0089] FIG. 12 illustrates an embodiment that is similar to that
shown in FIGS. 8 and 9. However, in this embodiment, one or more
solution generators 54 may be separate from cleaning head 22, and
located in front of scrubbing brush 26 (in the direction of
movement illustrated by arrow 16). For example, a line or row of
multiple solution generators 54 may be positioned in front of
scrubbing brush 26, similar to that shown in FIG. 9, but separate
from cleaning head 22. Furthermore, the line or row of multiple
solution generators 54 may be a linear row, an arced row (as
illustrated in FIG. 9), a staggered row, and the like. Examples of
suitable numbers of solution generators 54 in this embodiment range
from one to ten, or from two to eight, or from four to six. One of
the benefits of this design is the ability to retrofit solution
generators 54 into existing mobile floor cleaners.
[0090] FIG. 13 illustrates an embodiment that is similar to that
shown in FIG. 12, where cleaning head 22 is replaced with cleaning
head 122, which includes one or more soil transfer rollers or
extractor brushes 124 for cleaning soft floors. In this embodiment,
recovery system 64 may also include an additional vacuum extractor
tool (not shown) directed at rollers 124.
[0091] The rotation of rollers 124 (via motor 30) in the directions
indicated by the arrows results in portions of the rollers 124
being wetted with the generated cleaning solution, extracted by
rollers 124, and wiped or brushed against surface 18. For example,
as rollers 124 rotate, they engage the soft floor (e.g., carpet
fibers) and cause soil to be transferred from the carpet fibers to
rollers 124. Rollers 124 are further rotated and may optionally be
sprayed again by a separate nozzle (not shown). Subsequently, the
surfaces of rollers 124 may be vacuum extracted to remove the
soiled cleaning liquid from the rollers 124, which is conveyed into
recovery tank 74.
[0092] As can be seen, the line or row of solution generators 54 in
front of cleaning head 122 may function in the same manner as
discussed above for the embodiment shown in FIG. 12. This also
allows existing mobile floor cleaners having cleaning head 122 to
be retrofitted to incorporate solution generators 54.
[0093] FIGS. 14 and 15 depict another embodiment that incorporates
a cleaning head 126 as disclosed in U.S. Publication No.
2011/0219555, and which is modified to incorporate an elongated
solution generator. As shown in FIG. 14, cleaning head 126 is
configured to dispense the generated cleaning solution to surface
18 from within the interior of the cleaning head 126. Cleaning head
126 includes a cylindrical member 128 that is configured to engage
surface 18 and rotate about a central axis that is parallel to the
surface 18 being cleaned, during the performance of the cleaning
operation on surface 18.
[0094] In one embodiment, the rotation of cylindrical member 128 is
not directly driven by a motor, such as motor 30. This
non-motorized rotation of cylindrical member 128 means that, unlike
conventional floor cleaning heads, no motor is directly coupled to
cylindrical member 128 through a mechanical linkage of the cleaner,
such as a drive belt or gear train, through which the rotation of
cylindrical member 128 about its axis can be driven. Rather, the
rotation of cylindrical member 128 is driven solely by engagement
of cylindrical member 128 with surface 18 as mobile floor cleaner
10 travels across surface 18.
[0095] As further shown in FIG. 15, conduit 44 may connect to a
transducing dispenser tube 130 within the cylindrical member 128,
which may include one or more apertures or slots distributed along
the length of tube 130 to allow for substantially even dispensing
of the feed liquid 42 to the interior cavity of the cylindrical
member 128. As such, conduit 44 delivers a flow of feed liquid 42
into the interior cavity of the tube 130.
[0096] In the shown embodiment, dispenser tube 130 may include one
or more acoustic transducers (not shown) along its length or at its
end locations to generate acoustic waves (e.g., ultrasonic waves)
in the feed liquid 42 dispensed into the interior cavity of the
cylindrical member 128. In other words, dispenser tube 130 may
function as a transducing unit in a similar manner to transducing
unit 54 discussed above.
[0097] As further shown, cylindrical member 128 also includes a
tubular electrolysis cell 132, which may function in the same
manner as disclosed in U.S. Publication No. 2011/0219555.
Electrolysis cell 132 is correspondingly located within a porous
and rigid inner cylindrical wall 134, and a porous and compressible
outer cylindrical wall 136, as also disclosed in U.S. Publication
No. 2011/0219555.
[0098] In particular, the compressibility of the outer cylindrical
wall 136 can agitate the surface 18 using the generated cleaning
solution without sliding contact with surface 18. This occurs as
outer cylindrical wall 136 is first compressed against surface 18
and then decompressed as cylindrical member 128 rolls over surface
18. The compression of outer cylindrical wall 136 causes an initial
increase in pressure within its apertures. This pressure is
released when outer cylindrical wall 136 decompresses and expands
as cylindrical member 128 continues to rotate. This compression and
decompression operation moves the generated cleaning solution
proximate to the apertures, which encourage the release of dirt on
surface 18 for later collection by recovery system 64.
[0099] In this embodiment, the generated cleaning solution
typically forms a small pool in front of the rotating cylindrical
member 128 due to the compression of outer cylindrical wall 136.
While not wishing to be bound by theory, it is believed that the
pooling provides a suitable path for conducting the acoustic waves
(e.g., ultrasonic waves) from the transducer(s) to the surface 18
being cleaned, through the dispensed cleaning solution. This is
accordingly believed to provide suitable contact for the generated
cleaning solution to attract to and/or dislodge the contaminants
(e.g., dirt) on surface 18 prior to being drawn back by the
apertures in outer cylindrical wall 136. Thus, the cleaning
solution generated by the combination of acoustic energy (e.g.,
ultrasonic waves) and nanobubble generation is also suitable for
use with the compressible and rotatable cylindrical member 128.
[0100] As can be appreciated from the above embodiments, the
solution generator disclosed herein, which includes acoustic waves
through a feed liquid (e.g., with an ultrasonic transducer), and
generates nanobubbles in the liquid (e.g., with an electrolysis
cell or other nanobubble generator), is suitable for use with a
variety of different mobile floor cleaners. The resulting mobile
floor cleaners are then capable of generating cleaning solutions
from aqueous liquids (e.g., water) that have good cleaning
capabilities without additives such as detergents, while also
consuming lower amounts of electrical power, for example. This
correspondingly allows the mobile floor cleaners in some
embodiments to incorporate smaller and/or fewer batteries with
suitable operating durations.
[0101] While a solution generator according to the disclosure has
generally been described in the foregoing as being implemented on a
mobile floor cleaner, it should be recognized that other cleaning
applications or application for cleaning are possible in accordance
with the disclosure. As one example, the solution generator can be
implemented on a cleaning wand or cleaning stick that can be grasp
and manipulated by a human user. The user can control the cleaning
stick to provide localized cleaning to a soiled region, for
example, treating pernicious soils not readily released by mobile
floor cleaner 10.
[0102] FIG. 16 illustrates an example cleaning stick 200 that is
configured (e.g., sized and/or shaped) to be manipulated by a human
user and that incorporates a solution generator 54. Cleaning stick
200 may have an elongated shaft 202 that includes a handle portion
204 and a cleaning head 206. The cleaning head 206 can carry a
scrubbing brush, such as bristles, pads, or other fibers, that can
be used to apply abrasive friction to a surface to be cleaned. In
addition, cleaning head 206 can have one or more dispensing nozzles
or orifices 208 through which cleaning fluid is dispensed on a
surface to be cleaned. In operation, the user can grasp the handle
portion 202 of cleaning stick 200 and control the stick to dispense
cleaning fluid through dispensing orifice 208 onto a surface to be
cleaned. After dispensing the cleaning fluid or while dispensing
the cleaning fluid, the user can physically move the cleaning stick
to engage the scrubbing brush carried on cleaning head 206 with the
cleaning fluid dispensed on the surface to be cleaned. The
combination of localized application of cleaning fluid with
localized scrubbing action can help remove pernicious soils,
allowing an operator to perform selective "spot" treatment where
needed.
[0103] Solution generator 54 carried by cleaning stick 200 can be
implemented using any of the solution generator configurations
described herein. In one example, solution generator 54 includes a
nanobubble generator and a transducer unit. The solution generator
54 receives liquid from a reservoir, generates nanobubbles in the
liquid, and applies acoustic energy to the liquid. The nanobubble
generator can be implemented as an electrolysis cell that generates
the nanobubbles through electrolysis and/or a mechanical nanobubble
generator that generates the nanobubbles without the application of
electrical energy. The transducer unit can apply acoustic energy to
the liquid upstream and/or downstream of the nanobubble generator.
In another example, solution generator 54 includes either a
nanobubble generator or a transducer unit but not both features.
Other configurations of nanobubble generator are possible as
described herein.
[0104] To control dispensing of cleaning liquid from cleaning stick
200, the stick can have user controls (e.g., switches, buttons,
touchscreen interface, etc.). An operator can interact with the
user controls to control solution generator 54, causing the
solution generator to generate cleaning liquid that is then
dispensed on a surface at which the operator physically points
cleaning head 206. In one example, the user controls are positioned
on handle 202 of cleaning stick 200.
[0105] In the example of FIG. 16, cleaning stick 200 is illustrated
as being tethered to mobile floor cleaner 10, which may or may not
carry one or more solution generators 54 as described above.
Cleaning stick 200 can be tethered to mobile floor cleaner 10 via
one or more lines 210 that provide power and/or fluid to the
cleaning stick. For example, cleaning stick 200 may be tethered to
mobile floor cleaner 10 by a power line having an electrical
conductor and providing electricity from a battery carried by the
mobile floor cleaner. Additionally or alternatively, cleaning stick
200 may be tethered to mobile floor cleaner 10 by a fluid line
providing fluid communication between mobile floor cleaner 10 and
solution generator 56 carried on the cleaning stick. In operation,
liquid can flow from a fresh liquid supply reservoir carried on
mobile floor cleaner 10, through fluid line 210, to solution
generator 56 carried on cleaning stick 200. If cleaning stick 200
is configured with fluid removal means (e.g., suction), a separate
waste liquid line can provide fluid communication between the fluid
removal means and the waste liquid reservoir carried on mobile
floor cleaner 10.
[0106] Configuring cleaning stick 200 as a tethered unit to mobile
floor cleaner 10 can be useful so that power and/or fluid utilized
by the stick during cleaning operation are carried by mobile floor
cleaner 10. This can reduce the weight of cleaning stick 200,
making the stick easier to use and more maneuverable by the
operator. In addition, tethering cleaning stick 200 to mobile floor
cleaner 10 can ensure that the stick stays in close proximity to
the mobile floor cleaner. As the operator is performing a cleaning
operation using mobile floor cleaner 10, the operator can readily
access and use cleaning stick 200 to treat particularly pernicious
soils. In some such configurations, mobile floor cleaner 10
includes a mounting or carrying structure configured to receive and
hold cleaning stick 200 when the stick is not in use.
[0107] While tethering cleaning stick 200 to mobile floor cleaner
10 can be useful to access power and/or fluid storage on mobile
floor cleaner 10, in other configurations, cleaning stick 200 is
not tethered to the mobile floor cleaner. Rather, in these
configurations, cleaning stick 200 can have self-contained fluid
and/or power. For example, handle 202 of cleaning stick 200 can
contain batteries for supplying power and/or a fluid reservoir for
supplying liquid to solution generator 54. This can allow cleaning
stick to be readily portable to a wide range of locations.
[0108] Although the present disclosure has been described with
reference to preferred embodiments, workers skilled in the art will
recognize that changes may be made in form and detail without
departing from the spirit and scope of the disclosure.
* * * * *