Note: Descriptions are shown in the official language in which they were submitted.
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SELF-PROPELLED BRUSHLESS SURFACE CLEANER WITH RECLAMATION
Field of the Invention
The invention relates generally to surface cleaning
apparatus, and more particularly to a self-contained and
self-propelled brushless surface cleaner that effectively
scrubs a surface with pressurized/heated fluid, and that
reclaims both the fluid and contaminants loosened from a
surface during the cleaning thereof.
Background of the Invention
A variety of industrial-strength surface cleaners are
known in the prior art. In general, a pressurized cleaning
fluid is sprayed onto a surface to loosen dirt, rubber, oil,
grease, etc., that has been deposited on the surface during
the use thereof. The loosened dirt and other contaminants
are then vacuumed. Some surface cleaners filter out the dirt
and other contaminants in order to reuse the cleaning fluid.
Specific examples of prior art surface cleaners are noted
below.
U.S. Patent No. 3,959,020 discloses a surface cleaner
having a spray/vacuum head attached to the front of a tractor
and having mechanical systems mounted on a towed trailer.
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The spray/vacuum head has spray nozzles mounted in separate
fore and aft compartments thereof. A central compartment
positioned between the fore and aft compartments defines a
vacuum chamber. Holes are provided in a bottom wall of the
vacuum chamber adjacent. the surface to be cleaned. Air
vortexes are created at the holes as the vacuum is drawn
therethrough.
U.S. Patent No. 4,845,801 discloses a surface cleaning
vehicle having a forward-mounted low-pressure sprayer, an
aft-mounted high-pressure sprayer head and vacuum head
mounted aft of the high-pressure sprayer for vacuuming up
liquid and loose debris.
U.S. Patent No. 5,331,713 discloses a surface cleaning
vehicle having a front-mounted sprayer followed immediately
by rotating brush heads. A squeegee and vacuuming assembly
is mounted at the aft portion of the vehicle to vacuum up
cleaning liquid and debris.
U.S. Patent Nos. 5,287,589, 5,469,597 and 5,979,012
disclose surface cleaners having vehicle-mounted mechanical
systems coupled by long hoses to either walk-behind cleaning
heads or individual spray and vacuum wands. The walk-behind
cleaning heads or wands must be manually moved/manipulated
while the vehicle is frequently moved to a suitable support
distance.
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Unfortunately, none of the prior art surface cleaners is
able to achieve the combination of superior surface cleaning,
elimination of cleaning fluid runoff, complete cleaning fluid
reclamation., and efficient of operating manpower.
Summary of the Invention
Accordingly, it is an object of the present invention to
provide a surface cleaner having improved cleaning
capabilities .for cleaning hard flat industrial surfaces such
as ship decks, airport runways, streets, parking surfaces and
industrial floors.
Another object of the present invention is to provide a
surface cleaner that is totally self-contained.
Yet another object of the present invention is to
provide a surface cleaner that can be operated by a single
person.
Still another object of the present invention is to
provide a surface cleaner that effectively scrubs a surface
without the use of brushes or other types of surface-
contacting scrubbing devices.
A still further object of the present invention is to
provide a self-propelled surface cleaner that is easy to
maneuver on a surface to be cleaned.
Yet another object of the present invention is to
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provide a surface cleaner that reclaims its cleaning fluid
while trapping loosened surface contaminants in order to
prevent any toxic runoff.
Other objects and advantages of the present invention
will become more obvious hereinafter in the specification and
drawings.
In accordance with the present invention, a brushless
surface cleaner includes a vehicle having at least one drive
system for propelling the vehicle on a surface to be cleaned.
A cleaning head is mounted to the vehicle to extend forward
therefrom. The cleaning head has a deck and a skirt
extending from the deck such that when the skirt is placed in
contact with the surface to be cleaned, a cleaning volume is
bounded by the deck, skirt and surface to be cleaned. The
cleaning head further has at least one vent port formed in a
forward portion thereof and at least one vacuum port formed
in a rear portion thereof. A plurality of nozzles are
mounted for movement within the cleaning volume between the
forward and rear portions thereof when liquid under pressure
is supplied thereto and sprayed therefrom. A liquid supply
system is mounted on the vehicle for supplying the liquid
under pressure to the nozzles so that the surface to be
cleaned is effectively scrubbed by the liquid to produce a
mixture of the liquid and contaminants loosened from the
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surface to be Cleaned. A vacuum recycling system is mounted
on the vehicle anal coupled to the vacuum ports) for
suctioning the mixture, filtering the mixture to separate the
liquid from the contaminants and return the liquid so-
separated to the liquid supply system for reuse thereby.
Brief Description of the Drawings
Other objects, features and advantages of the present
invention will become apparent upon reference to the
following description of the preferred embodiments and to the
drawings, wherein corresponding reference characters indicate
corresponding parts throughout the several views of the
drawings and wherein:
FIG. Z is a side schematic view of an embodiment of the
self-propelled brushless surface cleaner according to the
present invention;
FIG. 2 is a front interior view of the surface cleaner's
cleaning head taken along line 2-2 of FTG. 1;
FIG. 3 is an isolated side view taken along line 3-3 of
DTG. 2-2 depicting the angular orientation of a pair of
nozzles coupled to a rotating arm in the present invention;
FIG. 4 is a side view of a portion of the cleaning head
taken along line 4-4 of FIG. 3 depicting the attachment of
the sealing band to the cleaning head's skirt;
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FIG. 5 is a top schematic view of an embodiment of the
baffle mounted in the vacuum tank of the vacuum/recycling
system; and
FIG. 6 is a schematic view of a plurality of bag filters
mounted in the vacuum tank for filtering large particles from
liquid passed therethrough.
Detailed Description of he Tnvention
Referring now to the drawings, and more particularly to
FIG. 1, a self-propelled brushless surface cleaner according
to the present invention is shown and referenced generally by
numeral 10. Surface cleaner 10 is a self-contained assembly
for cleaning a surface 100 over which it can be driven. Such
surfaces include, but~are not limited to, runways, streets,
sidewalks, parking surfaces, decks of ships and industrial
floor areas.
Surface cleaner l0 includes a self-propelled vehicle
having a frame 12, a drive train coupled to frame 12 that
includes a transmission ~14 coupled to rear wheels l8 (as
shown) and/or front wheels 16. Controls for driving surface
cleaner 10 and operating various systems thereon are provided
in a driver/operator compartment 20 at the front portion of
the vehicle. For reasons that will be explained further
below, transmission 14 can be selectively coupled to either
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an electric motor 22 or a combustion-engine motor 24 via an
operator-positioned switch 26. For reasons that will be
explained further below, the driving speed of surface cleaner
can be limited to a maximum speed by coupling a speed
limner or governor 34 to transmission 14. Another option is
to dictate a constant driving speed of surface cleaner 10 by
coupling a speed controller 36 to transmission 14.
Combustion-engine motor 24 can be any motor that runs on
a combustible fuel such as gasoline, diesel fuel, propane
gas, etc. Electric motor 22 can be powered by one or more
batteries 28 or by a DC current-producing alternator 30.
More specifically, alternator 30 is coupled mechanically to
combustion-engine motor 24 and electrically to a switch 32
that is selectively positioned to couple either batteries 28
or alternator 30 to electric motor 22. In this way, even if
batteries 28 run low during the cleaning operation, power for
electric motor 22 can simply be switched over to alternator
30 which is turned by combustion-engine 24. An AC voltage
generator 38 is also mechanically coupled to combustion-
engine motor 24 to produce an AC voltage for use by various
electrically-powered elements onboard surface cleaner 10 as
will be explained further below.
A cleaning head 40 is mounted at the front of surface
cleaner 10 by means of, for example, an arm 42 pivotally
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attached to frame 12 at pivot point 44. Arm 42 can be
manually pivoted or pivoted via a motorized force to
raise/lower cleaning head 40 and set a forward-to-rear pitch
angle of cleaning head 40 relative to surface 100.
Cleaning head 40 is defined by an inverted tray shape
having a top or deck 46 and a peripheral side skirt 48 that
extends down from deck 46 when cleaning head 40 is positioned
over surface 100 as shown. In use, when cleaning head 40 is
placed in contact with surface 100, (i . e. , a sealing band 70
contacts surface 100), a.cleaning volume 50 is defined by the
volume of air space bounded by deck 46 on its top, skirt 48
(to include band 70) on its sides and surface 100 at its
bottom. At the forward portion of cleaning head 40, one or
more vent ports 54 are provided. At the rear portion of
cleaning head 40, one or more vacuum portions 56 are
provided. By way of convention, the terms "forward" and
"rear" as used herein are relative to normal forward motion
of surface cleaner 10, i.e., front wheels 16 leading back
wheels 18.
Ports 54 and 56 are preferably formed in deck 46 and
allow outside air to communicate with cleaning volume 50.
The area defined by ports 54 should be approximately equal to
the area defined by ports) 56. However, the shape or number
of ports 54 or 56 is not a limitation of the present
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invention. An open-ended prior duct 60 can be attached to
deck 46 to effectively extend the height at which each port
54 communicates with the outside air. The function of duct
60 will be explained below.
Referring additionally to FIG. 2 which depicts a front
interior view of cleaning head 40 taken along line 2-2 in
FIG. 1, a pair of side-by-side arms 62 and 64 are rotatably
mounted to deck 46 by means of spindles 62A and 64A,
respectively. Each combination of spindles and arm (e. g.,
spindle 62A and arm 62) is also a conduit for delivering a
water supply to nozzles 66A/66B (mounted on arm 62) and
nozzles 68A/68B (mounted on arm 64). Arms 62 and 64 are
sized so that nozzles 66A/66B and 68A/68B experience movement
within cleaning volume 50 between ports 54 and 56. Each of
the nozzles is directed towards surface 100 at an acute angle
with respect to a surface-extending vertical line such that
when water is sprayed therefrom, arms 62 and 64 rotate
parallel to deck 46 on their respective spindles. For
example, as illustrated in FIG. 3, nozzles 66A and 66B are
directed at opposite acute angles 0 relative to an imaginary
vertical line 102 that is perpendicular to surface 100.
Acute angle A is typically in the range of approximately 15-
30E. Note that during testing of surface cleaner 10, it was
found that an angle 6 of approximately 30E provided the best
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cleaning results.
As mentioned above, attached to the lower periphery of
skirt 48 is a band 70 of flexible material that forms a seal
with surface 100. Band 70 is a strong but flexible material
that can withstand abrasion forces developed as cleaning head
40 moves over surface 100. A material that performed well in
testing of surface cleaner 10 is a multi-layered material
having alternating layers of rubber and nylon. This material
is available commercially from a variety of rubber
manufacturers such as B.F. Goodrich and Goodyear.
Referring now to FIG. 4, band 70 is mounted to skirt 48
using a plurality bolts/screws 72. Band 70 has elongated
slots 74 formed therethrough to receive bolts/screws 72. The
use of elongated slots 74 allows band 70 to be lowered as its
bottom edge 70A becomes worn/damaged. This effectively
increases the useful life of band 70.
Attached to the forward end of cleaning head 40 are a
plurality of spaced-apart wheel assemblies, one of which is
illustrated in FIG. land referenced generally by numeral 80.
The wheel assemblies support-cleaning head 40. Further, by
making the height of each wheel assembly 80 independently
adjustable, the side-to-side pitch of cleaning head 40 can be
adjusted. In general, a wheel assembly 80 includes a fixed
support 82 and an adjustable height support 84 coupled to a
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wheel 86. The particular configurations of support 82 and 84
are not limitations of the present invention.
Coupled to cleaning head 40 are a liquid (e. g., water)
delivery system and a vacuum/recycling system, both of which
are mounted on frame 12. Referring again to FIG. 1, the
basic elements of the liquid delivery system are contained
within dashed-line box. 90 and the basic elements of the
vacuum/recycling system are contained within dashed-line box
92. Electricity for various elements of systems 90 and 92 is
provided by generator 38 which is turned whenever combustion-
engine motor 24 is operating.
Liquid delivery system 90 includes a large water storage
tank 902 which can be baffled at 904 to prevent/minimize
sloshing forces when surface cleaner 10 is moving. A high-
pressure pump 906 is coupled to tank 902 to draw water
therefrom and pump same under high pressure to a boiler 908.
Although not shown for clarity of illustration, pump 906 is
typically a mechanically-driven pump that would be coupled to
combustion-engine motor 24 as would be well understood in the
art. For longevity of service, boiler 908 can be constructed
entirely of stainless steel.
Water under pressure circulates through boiler 908 and
exits same at a set elevated temperature. The heated and
pressurized water is supplied at 901 to nozzles 66A/66B and
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68A/68B via spindle 62A/arm 62 and spindle 64A/arm 64,
respectively, thereby causing each arm to rotate within
cleaning volume 50 as water is sprayed onto surface 100.
Vacuum/recycling system 92 includes a blower-type vacuum
920 having its blowing vent side vented at 92,2 and its
suction side coupled to a vacuum tank 924. Vacuum tank 924
is a sealed tank ported at 926 and 928. Ports 926 and 928
should define approximately equal areas. Port 926 has a
larger-particle filter,930 coupled thereto and port 928 has 'a
baffle 932 coupled thereto. Filter 930 and baffle 932 reside
in the air space of vacuum tank 924, and will be explained
further below. A pump 934 (e.g. , a sump pump) is mounted in
the lower (fluid-filled) portion of vacuum tank 924. Pump
934 pumps fluid 936 through one or more particle filters 938.
Tf a plurality of filters 938 are used, they would typically
be coupled in series in descending order of particle sizes to
be filtered. The particle-strained fluid is then passed
through an oil separator 940 (e. g., a coalesce filter as they
are known in the art). The fluid exiting oil separator 940
is clean water that is returned to tank 902 for reuse in the
cleaning process. Port 926 is coupled via~hose 942 to vacuum
port (s) 56.
The details of an embodiment of baffle 932 are
illustrated in FTG. 5 where a box-like structure 932A is
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attached to vacuum tank 924. In the top view shown in FIG.
5, only the sides of box-like outer structure 932A are shown.
However, it is to be understood that outer structure 932A
includes a tap and bottom. A narrow slot or port 932B is
formed between outer structure 932A and tank 924. The area
of port 932B matches that of port 928. A baffle plate 932C
in outer structure 932A defines a tortuous path 932D through
baffle 932 so that any of liquid 936 drawn up towards port
928 (by the vacuum force drawn through port 928) is entrained
by baffle 932.
An embodiment of Large particle filters) 930 is
illustrated in FIG. 6 where a plurality of bag filters 930A,
930B, etc., are coupled in parallel to port 926. Each of the
bag filters traps larger particles (e.g., 100 microns or
greater) while allowing the mixture of liquid and smaller
particles to pass therethrough as liquid 936 that falls via
gravity to the lower portion of vacuum tank 924.
In operation, surface cleaner 10 has tank 902 filled
with water and is driven to a site to be cleaned. When
driving to a site, switch 26 will normally be positioned to
couple combustion-engine 24~to transmission 14. Once surface
cleaner 10 is in position to begin cleaning, switch 26 is
positioned so that electric motor 22 is coupled to
transmission 14. Combustion-engine motor 24 continues running
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to turn alternator 30 and generator 38, as well as provide
the mechanical drive for elements such as pump 906. Cleaning
head 40 is lowered onto surface 100 with its front-to-rear
and side-to-side pitch being set to accommodate surface 100.
Systems 90 and 92 are turned on and surface cleaner 10 is
driven over surface 100.
Heated water under pressure is sprayed from nozzles
66A/66B and. 68A/68B causing arms 62 and 64, respectively, to
rotate between ports 54 and 56 as described above. The hot,
pressurized water loosens solid debris and other contaminants
from surface 100. A vacuum force created by vacuum/recycling
system 92 is applied through hose 942 to ports) 56. The
suction force from this vacuum draws outside air into
cleaning volume 50 via ducts) 60. The use of ducts 60
prevent water sprayed into cleaning volume 50 from escaping
therefrom via ports) 54. The resulting air flow into and
through cleaning volume 50 is illustrated at 200. By placing
ports) 54 and 56 at the respective forward and rear portions
of cleaning volume 50, a high-pressure air flow is drawn over
surface 100 in the area where high-pressure water is being
sprayed. This large area of high-pressure air flow serves to
not only pick' up the water and loosened debris/contaminants,
but also frees debris/contaminants partially loosened by the
high-pressure water spray. Placing ports 54 and 56 in the
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top of cleaning volume 50 (i.e., in deck 46) has the further
advantage of allowing the downward rush of air passing
through duct (s) 60 and port (s) 54 to strike surface 100 to
aid in loosening contaminants from surface 100. The
resulting mixture 202 of water and loosened
debris/contaminants is drawn into hose 942 and delivered to
vacuum tank 924. During testing of surface cleaner 10, the
best cleaning results were obtained when water at a
temperature of approximately 1500F was delivered from nozzles
66A/66B and 68A/68B at a flow rate of approximately 13
gallons per minute (gpm) and a pressure of approximately 4000
pounds per square inch (psi), while maintaining a vacuum of
approximately 400 cubic feet per minute (cfm).
Mixture 202 is first filtered by large particle
filters) 930 where larger solid particles are trapped and. a
partially filtered liquid is deposited via gravity as liquid
936 in the lower portion of tank 924. Pump 934, filter (s)
938 and oil separator 940 function as described above to
return clean water to tank 902.
During the cleaning process, surface cleaner 10 is
driven under the power of electric motor 22 because of its
smoother delivery of power to transmission 14 as compared to
combustion-engine motor 24. For optimum cleaning, cleaning
head .40 should move at a relatively constant speed over
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surface 100. This constraint is simplified for an operator
by powering transmission 14 via electric motor 22. For
greater precision, a consistent speed could be maintained
automatically by use of speed control 36. Furthermore,
optimum cleaning is obtained by assuring that cleaning head
40 is positioned over each area of surface 100 for a certain
period of time. This is achieved by not driving surface
cleaner 20 to quickly over surface 100. Once again, while
this quality control measure can be left up to the operator,
speed limiter 34 can be coupled to transmission 14 during the
cleaning operation to assure that the maximum (optimum
cleaning) speed for a particular surface is not exceeded.
For safety reasons, the use of speed limner 34 may be
preferred to speed control 36.
The advantages of the present invention are numerous.
Improved surface cleaning is achieved by a uniquely-designed
cleaning head that uses both high-pressure water and a
uniquely directed vacuum flow to remove the maximum amount of
debris/contaminants from a surface using only hot water. The
surface cleaner is self-contained and self-propelled so that
it~ can be efficiently operated by one person. The
contaminated cleaning water is reclaimed for reuse. Further,
since the spray/vacuum operation is contained within a single
cleaning head, there is no toxic runoff generated by the
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cleaning operation. The surface cleaner can be propelled
smoothly by an electric motor for optimum cleaning while
simultaneously using a combustion-engine motor to charge
batteries and drive various mechanical systems.
Although the invention has been described relative to a
specific embodiment thereof, there are numerous variations
and modifications that will be readily apparent to those
skilled in the art in light of the above teachings. It is
therefore to be understood that, within the scope of the
appended claims, the invention may be practiced other than as
specifically described.
What is claimed as new and desired to be secured by
Letters Patent of the United States is:
