U.S. patent application number 10/905575 was filed with the patent office on 2006-07-13 for orbital scrubber.
This patent application is currently assigned to ALTO U.S. INC.. Invention is credited to Kevin Blaine Mitchell.
Application Number | 20060150362 10/905575 |
Document ID | / |
Family ID | 35429270 |
Filed Date | 2006-07-13 |
United States Patent
Application |
20060150362 |
Kind Code |
A1 |
Mitchell; Kevin Blaine |
July 13, 2006 |
ORBITAL SCRUBBER
Abstract
This orbital motion scrubber uses less cleaning solution than
many conventional rotary motion scrubbers of comparable scrub width
and tank size, which results in longer solution run time. The
present invention drives the cleaning element in a high speed
orbital motion which results in more revolutions per spot than many
conventional rotary motion scrubbers. A flexible pad driver
produces better cleaning of uneven hard surface floors than some
prior art designs with rigid pad drivers. The brush motor that
drives the pad driver and the cleaning element of the present
invention uses less electrical energy than the brush motor in many
rotary motion scrubbers which results in longer battery run
time.
Inventors: |
Mitchell; Kevin Blaine;
(West Fork, AR) |
Correspondence
Address: |
BLACKWELL SANDERS PEPER MARTIN LLP
720 OLIVE STREET
SUITE 2400
ST. LOUIS
MO
63101
US
|
Assignee: |
ALTO U.S. INC.
16253 Swingley Ridge Road Suite 200
Chesterfield
MO
|
Family ID: |
35429270 |
Appl. No.: |
10/905575 |
Filed: |
January 11, 2005 |
Current U.S.
Class: |
15/320 |
Current CPC
Class: |
A47L 11/4044 20130101;
A47L 11/305 20130101; A47L 11/408 20130101; A47L 11/4036 20130101;
A47L 11/4069 20130101 |
Class at
Publication: |
015/320 |
International
Class: |
A47L 11/30 20060101
A47L011/30 |
Claims
1-43. (canceled)
44. A method of cleaning a hard floor surface with a floor
scrubber, the method comprising the steps of: applying liquid
cleaning solution to the hard floor surface in the proximity of a
forward edge of a flexible cleaning element; scrubbing the wet hard
floor surface by movement of a flexible pad driver and a flexible
cleaning element in an orbital path to loosen soil from the hard
floor surface leaving behind a soiled solution; applying an
adjustable load on the flexible pad driver and flexible cleaning
pad depending on how dirty the hard floor surface may be; and
removing at least a portion of the soiled solution from the hard
floor surface through a fluid recovery device.
45-47. (canceled)
48. A method of cleaning a hard floor surface with a floor scrubber
free of splash skirts, the method comprising the steps of: placing
a cleaning solution of water and concentrated floor soap in a
solution tank of the floor scrubber; contacting the hard floor
surface with the cleaning solution; scrubbing the wetted hard floor
surface by movement of a flexible pad driver and the flexible
cleaning element in an orbital path to loosen soil from the hard
floor surface leaving behind a soiled solution; placing an
adjustable load on the flexible pad driver and the cleaning element
to allow for accommodation of heavily soiled floor surfaces and
those that are lightly soiled; and removing at least a portion of
the soiled solution from the hard floor surface through a vacuum
squeegee.
49-51. (canceled)
52. A floor scrubber having at least one rechargeable battery, a
solution tank to hold a cleaning solution, a squeegee to pick up a
dirty fluid which is held in a recovery tank, the floor scrubber to
clean hard floor surfaces characterized by: a cleaning head
assembly having; i) a flexible pad driver; ii) a removable cleaning
element; and iii) a motor and eccentric cam to impart orbital
movement to the flexible pad driver and the removable cleaning
element.
53. The floor scrubber of claim 52, further including: an
adjustable actuator to impart a variable amount of load on the
flexible pad driver and the removable cleaning element.
54. The floor scrubber of claim 52, further including a cleaning
solution distribution tube with a plurality of holes to apply
liquid cleaning solution at a flow rate so no splash skirts are
needed on the cleaning head assembly.
55. The floor scrubber of claim 52, wherein the flexible pad driver
is formed from plastic.
56. The floor scrubber of claim 52, wherein the flexible pad driver
is selected from the group consisting of plastic and nylon.
57. The floor scrubber of claim 52 further including a plurality of
vibration dampening elements to connect a motor mounting plate to
the flexible pad driver.
58. The floor scrubber of claim 52 further including attaching
means to attach the removable cleaning element to the flexible pad
driver.
59. The floor scrubber of claim 58 wherein the attaching means to
attach the removable cleaning element to the flexible pad driver is
tool free.
60. A method of cleaning a hard floor surface with a floor
scrubber, the method comprising the steps of: contacting the hard
floor surface with a cleaning solution; and scrubbing the wetted
hard floor surface with a removable cleaning element driven by a
flexible pad driver in an orbital motion by a motor and eccentric
cam.
61. The method of claim 60 further including the steps of: applying
an adjustable load to the flexible pad driver and the removable
cleaning element with an actuator, to allow for accommodation of
heavily soiled floor surfaces and those that are lightly soiled;
and removing at least a portion of the soiled solution from the
hard floor surface through a vacuum squeegee.
62. A cleaning head assembly for use with a floor scrubber to clean
hard floor surfaces, comprising: a flexible pad driver; a removable
cleaning element; means for attaching the removable cleaning
element to the flexible pad driver; and means for imparting orbital
movement to the flexible pad driver and the removable cleaning
element.
63. A cleaning head assembly for use with a floor scrubber to clean
hard floor surfaces, comprising: a flexible pad driver; a removable
cleaning element; a plurality of connecting elements to attach the
removable cleaning element to the flexible pad driver; and a brush
motor and eccentric cam to impart orbital movement to the flexible
pad driver.
64. A cleaning head assembly for use with a floor scrubber to clean
hard floor surfaces, comprising: a motor mounted on a motor
mounting plate, the brush motor drawing greater than about 8 amps.
and less than about 18 amps.; a flexible pad driver; a removable
cleaning element operatively connected to the flexible pad driver;
and means for driving the cleaning element in an orbital motion in
contact with the floor surface.
65. A cleaning head assembly for use with a floor scrubber to clean
hard floor surfaces, comprising: a flexible pad driver; a removable
cleaning element operatively connected to the flexible pad driver;
a motor and eccentric cam to impart orbital movement to the
flexible pad driver and the removable cleaning element; and the
motor drawing greater than about 8 amps. and less than about 18
amps.
66. A floor scrubber to clean hard floor surfaces, the scrubber
having a cleaning head assembly comprising: a flexible pad driver;
a removable cleaning element; means for attaching the removable
cleaning element to the flexible pad driver; and means for
imparting orbital movement to the flexible pad driver and the
removable cleaning element.
67. A floor scrubber to clean hard floor surfaces, the scrubber
having a cleaning head assembly comprising: a flexible pad driver;
a removable cleaning element; a plurality of connecting elements to
attach the removable cleaning element to the flexible pad driver;
and a brush motor and eccentric cam to impart orbital movement to
the flexible pad driver.
68. The floor scrubber of claim 67 wherein the connecting elements
to attach the removable cleaning element to the flexible pad driver
is tool Thee.
69. A floor scrubber to clean hard floor surfaces, the scrubber
having a cleaning head assembly comprising: a motor mounted on a
motor mounting plate, the brush motor drawing greater than about 8
amps. and less than about 18 amps.; a flexible pad driver; a
removable cleaning element operatively connected to the flexible
pad driver; means for driving the cleaning element in an orbital
motion in contact with the floor surface.
70. A floor scrubber to clean hard floor surfaces, the scrubber
having a cleaning head assembly comprising: a flexible pad driver;
a removable cleaning element operatively connected to the flexible
pad driver; a motor and eccentric cam to impart orbital movement to
the flexible pad driver and the removable cleaning element; and the
motor drawing greater than about 8 amps. and less than about 18
amps.
71. A floor scrubber to clean hard floor surfaces, the floor
scrubber having at least one rechargeable battery, a solution tank
to hold a cleaning solution, a squeegee to pick up a dirty fluid
which is held in a recovery tank, the floor scrubber comprising: a
cleaning head assembly having; i) a flexible pad driver; ii) a
removable cleaning element; and iii) a motor and eccentric cam to
impart orbital movement to the flexible pad driver and the
removable cleaning element; and an adjustable actuator to impart a
variable amount of load on the flexible pad driver and the
removable cleaning element.
72. A floor scrubber to clean hard floor surfaces, comprising: a
cleaning head assembly comprising: a flexible pad driver; a
removable cleaning element; means for attaching the removable
cleaning element to the flexible pad driver; and means for
imparting orbital movement to the flexible pad driver and the
removable cleaning element; and means for imparting a variable
amount of load on the flexible pad driver and the removable
cleaning element.
73 The floor scrubber of claim 72 wherein the means for attaching
the removable cleaning element to the flexible pad driver is tool
free.
74. A floor scrubber to clean hard floor surfaces, comprising: a
cleaning head assembly comprising; a flexible pad driver; a
removable cleaning element; a plurality of connecting elements to
attach the removable cleaning element to the flexible pad driver;
and a brush motor and eccentric cam to impart orbital movement to
the flexible pad driver; and an adjustable actuator to impart a
variable amount of load on the flexible pad driver and the
removable cleaning element.
75. A floor scrubber to clean hard floor surfaces, comprising: a
cleaning head assembly comprising; a motor mounted on a motor
mounting plate, the brush motor drawing greater than about 8 amps.
and less than about 18 amps.; a flexible pad driver; a removable
cleaning element operatively connected to the flexible pad driver;
and means for driving the cleaning element in an orbital motion in
contact with the floor surface; and an adjustable actuator to
impart a variable amount of load on the flexible pad driver and the
removable cleaning element.
76. A floor scrubber to clean hard floor surfaces, comprising: a
cleaning head assembly comprising; a flexible pad driver; a
removable cleaning element -operatively connected to the flexible
pad driver: a motor and eccentric cam to impart orbital movement to
the flexible pad driver and the removable cleaning element; and the
motor drawing greater than about 8 amps. and less than about 18
amps.; and an adjustable actuator to impart a variable amount of
load on the flexible pad driver and the removable cleaning element.
Description
BACKGROUND OF INVENTION
[0001] Rotary type scrubbers have been used for decades to clean
hard floor surfaces such as tile, linoleum, and concrete. These
hard floor surfaces are often uneven which presents challenges to
the scrubber and may result in a floor that is not cleaned in a
uniform fashion. One approach to uneven floors is a gimbaled disc
shaped scrub brush. The gimbaled design allows some degree of
freedom to the brush allowing it to tilt in response to the uneven
floor.
[0002] Another challenge to conventional floor cleaning is excess
water consumption. In the past, it was a widely held belief that
the more water that was applied to the floor, the cleaner it could
be scrubbed. Within the last few years, this notion has fallen from
favor as the floor cleaning industry has become more ecologically
conscious. Various approaches have been developed by several floor
equipment companies using rotary type scrubbers discussed
below.
[0003] One approach to the challenge of excess water consumption
was developed by the Tennant Company of Minneapolis, Minn.
(www.tennantco.com) and is disclosed in U.S. Pat. Nos. 6,585,827;
6,705,332 and 6,705,662. Tennant calls this the FaST.TM. foam
scrubbing technology. Tennant promotional material represents that
this technology increases scrubbing productivity up to 30% for
rotary type scrubbers. However, this rotary type scrubber still has
splash skirts.
[0004] Yet another approach to the challenge of excess water
consumption was developed by Windsor Industries of Denver, Colo.
(www.windsorind.com and is referred to as the Aqua-Mizer.TM. which
is disclosed in a published patent application entitled "Scrubbing
Machine Passive Recycling", published Apr. 17, 2003, Publication
Number 2003-0070252. . Windsor promotional material represents that
this technology increases run-time productivity by 35 to 50% per
tank fill up. This system apparently is standard on all of the
Windsor Saber Cutter models which are rotary type scrubbers.
However, this rotary type scrubber still has splash skirts.
[0005] A different approach to the challenge of excess water
consumption has been developed by Penguin Wax Co. Ltd., of Osaka,
Japan (www.penguinwas.co.jp). Penguin offers a scrubber called the
"Shuttlematic" model numbers SQ 200 and the SQ 240. Instead of the
rotary motion of the aforementioned floor scrubbers, the
Shuttlematic uses two flat pads positioned perpendicular to the
direction of travel of the machine. Penguin promotional material
represents that the Shuttlematic has longer run time, less power
consumption and no water splash. The Shuttlematic does not have
splash skirts. Another prior art shuttle type design without splash
skirts is disclosed in U.S. Pat. No. 1,472,208. The shuttle motion
of the '208 Patent is different from the shuttle motion of the
Shuttlematic. Notwithstanding the aforementioned prior art
scrubbers, there is still a need for a floor cleaning machine that
will conserve water and power and still do a good job scrubbing
uneven hard floor surfaces.
[0006] Applicant has developed a different approach that conserves
water and power and still does an excellent job scrubbing uneven
hard floor surfaces. The present invention is an orbital scrubber.
It is a marriage between some of the features found in prior art
rotary motion scrubbers for hard floor surfaces and some of the
features found in prior art orbital motion sanders for finishing
wood floors. Applicant's assignee of the present invention, Clarke,
a division of ALTO U.S. Inc. has previously sold an orbital motion
sander for finishing wood floors, model number OBS 18, among
others, as pictured on the advertisement and operator's manual
included in the information disclosure statement filed concurrently
herewith. This orbital motion has been combined with some of the
features of the prior art rotary motion Encore scrubbers also sold
by Clarke, a division of ALTO U.S. Inc. Operator's manuals for
various Encore rotary motion scrubbers are likewise included in the
information disclosure statement filed concurrently herewith.
[0007] In the mid-1960's, Clarke introduced an orbital motion
scrubber for hard floor surfaces, model number BP-18-SP, which was
on sale for several years during which more than a thousand units
were sold. The BP-18 did a poor job cleaning uneven floors.
Apparently, customers would make an initial purchase, but follow-up
sales were difficult to close because of the uneven cleaning
problem. Sales eventually dried up. The BP-18 had a high solution
flow rate of approximately 1.1 gallons per minute at the full flow
setting and therefore required splash skirts around the cleaning
head assembly. In contrast, the present invention uses
comparatively low cleaning solution flow rates and therefore no
splash skirts are needed. The BP-18 was a failed attempt from the
mid-1960's at an orbital motion scrubber.
[0008] The BP-18 failed for a number of reasons, but certainly one
of the reasons was because the pad driver was a rigid piece of
metal that did not flex in response to uneven features in the
floor. As a result, the cleaning was uneven. The cleaning pad on
the BP-18 was thin and thus easily damaged. (This prior art
cleaning pad was about 0.19 inches thick). Furthermore, tools were
required to make a pad change. Further, the BP-18 had a fixed
weight of 35 pounds that applied this non-adjustable load on the
cleaning head. Notwithstanding this prior art orbital motion
scrubber for hard floor surfaces, and prior art orbital motion
sanders for finishing wood floors and prior art rotary motion
scrubbers, there is still a need for a floor cleaning machine that
will conserve water and power and still do a good job scrubbing
uneven hard floor surfaces.
SUMMARY OF THE INVENTION
[0009] The present invention uses high speed orbital motion to move
a flexible pad driver attached to a removable cleaning element. The
cleaning element makes more revolutions per spot on the floor than
many conventional rotary motion scrubbers. The term "cleaning
element" as used herein includes both cleaning pads and brushes
with bristles. Unlike some prior art attempts, no tools are
required to change the cleaning element on the present invention.
Cleaning solution is evenly applied to the floor immediately in
front of the cleaning element in quantities that are comparatively
less than usage of many conventional rotary motion scrubbers of
comparable scrub width. Less cleaning solution consumption equates
to a longer run time between tank refills. Because less cleaning
solution is used, the present invention does not need or have
splash skirts. The absence of splash skirts allows the orbital
scrubber to get into tight places and into a square corner. The
orbital scrubber also uses less electrical energy than conventional
rotary motion scrubbers of comparable scrub width. A flexible pad
driver results in better cleaning of uneven floor surfaces than
some prior art designs with rigid pad drivers.
BRIEF DESCRIPTION OF DRAWINGS
[0010] FIG. 1 is a schematic of a prior art rotary motion
scrubber.
[0011] FIG. 2 is a side view of the present invention, the orbital
scrubber.
[0012] FIG. 3 is a front view of the cleaning head of the orbital
scrubber of FIG. 2.
[0013] FIG. 4 is an exploded front view of the cleaning head of
FIG. 3.
[0014] FIG. 5 is an exploded side view of the cleaning head of FIG.
3.
[0015] FIG. 6 is a front view of the cleaning head of FIG. 3 when
it encounters an uneven floor surface.
[0016] FIG. 7 is a side view of the cleaning head of FIG. 3 as it
flexes to scrub an uneven floor surface.
[0017] FIG. 8 is an exploded perspective view of the cleaning head
and the front of the orbital scrubber.
[0018] FIG. 9 is a cross-sectional view of a vibration dampening
element.
[0019] FIG. 10 is a perspective view of a flexible pad driver and a
removable cleaning brush.
DETAILED DESCRIPTION
[0020] FIG. 1 is a schematic diagram of a prior art rotary motion
type scrubber generally identified by the numeral 20. These
scrubbers can use disc shaped brushes or cleaning pads that operate
in a rotary motion about the shaft of the brush motor. These
scrubbers are therefore referred to herein as rotary motion type
scrubbers. Scrubbers of this type are designed to clean hard floor
surfaces such as tile, linoleum, and concrete. These rotary motion
scrubbers are typically used in medical facilities, office
buildings, educational facilities, restaurants, convenience stores,
and grocery stores.
[0021] The operator, not shown, walks behind the scrubber 20 and
grips the handle 18 to control the direction of travel as indicated
by the arrow at the front of the scrubber. A control panel 16 is
positioned at the rear of the scrubber and has various control
devices and systems well known to those skilled in the art. The
control devices and systems are in electrical connection with the
various operating components of the scrubber. There is no
standardized set of control devices and systems on each and every
rotary scrubber, but the following are available on some rotary
scrubbers.
[0022] There is typically an on/off switch, not shown, and a
cleaning head assembly position control device. The cleaning head
assembly typically has an upper position where the brush bristles
are not in contact with the floor surface and a lower position
where the brush bristles are in contact with the floor surface.
When the on/off switch is "on" and the cleaning head assembly is
put in the lower position, a touch down switch, not shown,
activates the brush motor to scrub the floor.
[0023] There may be a control device to vary the amount of downward
load on the cleaning head assembly. Some scrubbers have an
adjustable actuator that varies the amount of downward load on the
cleaning head assembly. Some scrubbers have weights on the cleaning
head assembly that exert a constant load. For those scrubbers with
adjustable load control devices, a heavy load is used for very
dirty floors. Lightly soiled floors require minimum load. The
heavier the load on the cleaning head assembly, the higher the amp.
draw of the brush motor and the less the battery run time. The amp.
draw of a 3/4 HP brush motor for the present invention is greater
than about 8 amps. and less than about 18 amps. depending on the
amount of the downward load on the cleaning head.
[0024] There may be an adjustable speed control device, not shown,
to control the speed of the traction motor which dictates the
forward speed of the scrubber. Some scrubbers do not have traction
motors and rely on the rotation of the brushes to help move the
machine forward. However, on those scrubbers that have traction
motors, the faster the speed the higher the amp. draw which reduces
battery run time and vice-a-versa.
[0025] There may also be an adjustable flow control device, not
shown, for the cleaning solution. There is typically a squeegee
position control device, not shown. The squeegee 34 typically has a
full up, full down and medium height position, which is typically a
manual lever. The squeegee 34 also has a touch down switch, not
shown, to turn on the vacuum motor 38 when the squeegee 34 is in
the full down position to suck up dirty fluid 41. The medium
setting on the squeegee 34 is to clear the squeegee conduit 32 when
scrubbing is complete so it does not drip dirty fluid on a clean
floor or elsewhere. The full up position is used to move the
scrubber 20 from place to place when scrubbing is not desired, as
over clean floors, or back to the janitor's closet to drain the
recovery tank 24 and refill the solution tank 22.
[0026] The rotary motion scrubber 20 has a solution tank 22 and a
recovery tank 24. A brush motor 26 drives a disc shaped brush 28
which has bristles 25 which engage the hard surface floor 30. A
conduit 32 connects the squeegee 34 to the recovery tank 24. A
conduit 36 connects the recovery tank 23 with the vacuum motor 38
which is vented to atmosphere. A drain 40 is used to drain the
dirty fluid 41 from the recovery tank 24.
[0027] Concentrated cleaning solution 43 is poured into the
solution tank 22 through the solution tank inlet 42. The cleaning
solution 43 is a liquid and typically includes a mixture of tap
water and a cleaning agent such as concentrated floor soap.
Typically, the concentrated cleaning agent is poured into the
solution tank 22 and then tap water is added in the desired amount.
In most situations, the solution tank 22 is filled to the top with
water and concentrated floor soap. When the scrubber is scrubbing,
the cleaning solution 43 passes from the solution tank 22 through
the solution conduit 44 to the brush 28. The cleaning solution is
then scrubbed against the floor 30 by the rotating bristles 25 of
the brush 28. As the scrubber 20 moves forward as indicated by the
arrow 52, a squeegee 34 sucks up the dirty fluid 41 from the floor
30 and the dirty fluid moves through the conduit 32 into the
recovery tank 24.
[0028] As shown in FIG. 1 the scrubber 20 has just begun a shift
and there is more cleaning solution 43 in the solution tank 22, as
indicated by the fluid level line 54 than dirty fluid 41 in the
recovery tank as indicated by the fluid level line 56. However,
when the recovery tank 24 is full as indicated by the dashed fluid
level line 58, the solution tank 22 will be empty or nearly empty
as indicted by the dashed fluid level line 60. When the recovery
tank is full as indicated by the fluid level line 58, a float shut
off switch turns off the brush motor 26 and the vacuum motor 38.
The operator therefore knows it is time take the scrubber to a
janitor's closet or other suitable location to drain the recovery
tank through the drain 40. The process is then repeated. The
solution tank 22 is refilled with a mixture of water and
concentrated cleaning solution 43 and the scrubber can be taken
back to a work area and can recommence scrubbing the floor. The
batteries 64 are typically recharged overnight after the job is
completed.
[0029] Most scrubbers, like the scrubber 20 have traction wheels 62
that facilitate movement of the scrubber to and from the work area
to the janitor's closet. Some scrubbers have a traction motor, not
shown to power the traction wheels 62. All scrubbers like the
scrubber 20 have a power supply to power the brush motor 26, the
vacuum motor 38 and if so equipped, the traction motor. In some
scrubbers, the power supply is two or more 12 or 6-volt DC
rechargeable batteries 64, mentioned above. In other scrubbers the
power supply is 110 volts AC or 220 volts AC. When AC powered, the
scrubber has a long extension cord used to access wall mounted AC
receptacles.
[0030] While scrubbing, cleaning solution 43 passes through the
cleaning solution conduit 44 and feeds out by gravity to the top of
the brush 27. The brush has a plurality of holes 29 through the top
of the brush 27 that allow some of the cleaning solution 43 to pass
through the brush to the bristles 25 and the floor 30.
Unfortunately, the brush 28 is rotating at about 200-300 RPM so
much of the cleaning solution 43 is flung off the top of the brush
27 by centrifugal force. Splash skirts 31 surround the brushes 28
to contain the cleaning solution that is being flung off the top of
the brush 27. To Applicant's knowledge, all rotary motion floor
scrubbers have some type of splash skirt to contain the cleaning
solution that is flung off the top of the brush 27. The cleaning
head is generally identified in FIG. 1 by the numeral 66. The
cleaning head is an assembly that typically includes one or two
brushes contained by a splash skirt on the front and sides of the
cleaning head. In the industry, the terms cleaning head, rotary
head, scrub head and brush head are used interchangeably.
[0031] An actuator, not shown applies downward forces on the
cleaning head 66 to facilitate cleaning of uneven floors. Really
dirty floors require more load on the cleaning head 66. However,
heavier loads on the cleaning head 66 require more electricity to
drive the brush 28. The load or downward pressure on the cleaning
head can be up to about 200 lbs. depending on the machine. For
example, the Clarke, Encore 17'' scrubber can apply from 0 to about
90 lbs. of force on the cleaning head; the Encore 24''-26''
scrubbers can apply from 0 to about 150 lbs. of force on the
cleaning head. The Encore 28'' to 38'' can apply from about 120
lbs. to about 220 lbs of force to the cleaning head. The cleaning
head 66 can be moved from the lower position shown in FIG. 1 where
the bristles 25 engage the floor 30 to an upper position, not
shown, so the bristles do not touch the floor. The upper position
is used when the scrubber needs to be moved about from one place to
the next. The lower position, shown in FIG. 1 is used when the
floor cleaning machine is scrubbing the floor.
[0032] The Encore 2426 has a "battery run time" of about 3-4 hours
before the rotary scrubber needs to be recharged. The Encore 2426
has a "solution run time" between tank refillings/emptying of about
one hour. In other words, it takes about one hour of floor
scrubbing to use all of the cleaning solution in the 20 gal.
solution tank, at the half flow setting. Then it is time to take
the rotary motion scrubber to the deep sink in the janitors' closet
or other suitable location for draining. The recovery tank is then
refilled with cleaning solution and the scrubber is taken back to
the work area for more scrubbing. It may take the operator 30-40
minutes to complete a refill cycle including the trip back and
forth to and from the deep sink. So if the number of refills per
hour can be reduced it means time saved and is an advantage for any
floor cleaning machine.
[0033] One reason the Encore 2426 uses so much cleaning solution is
the disc type brush that rotates at approximately 200 RPM. As
previously discussed, the centrifugal force created by rotation to
the disc type brush drives the cleaning solution away from the
brush and bristles. This solution never gets used for scrubbing
purposes and is controlled by the splash skirt and picked up by the
squeegee. These brushes may be adjusted from a width of about 24
inches to a width of about 26 inches and thus the model number
2426.
[0034] The present invention in the 2426 version can use a 3/4 HP
direct drive brush motor which causes the cleaning element to orbit
at about 2,250 RPM. The 3/4 HP brush motor will draw about 10-14
amps while scrubbing. But because the motion is orbital rather than
rotational, the cleaning solution is not driven away from the
cleaning pad so less cleaning solution is needed for the same
amount of floor space and no splash skirts are required. In
addition, because the motor draws less current it may also extend
the run time of the batteries.
[0035] The present invention in a 2426 version has a battery run
time of about of about 5-6 hours before the orbital scrubber needs
to be recharged. The present invention in a 2426 version with a 20
gal. solution tank has a solution run time at the half flow setting
of about 100 minutes; whereas, the Encore 2426 with a 20 gal.
solution tank has a solution run time at half flow setting of about
57 minutes. For comparison purposes, the present invention, with a
20 gal. solution tank uses about 0.6 refills per hour (60 min./100
min), at the half flow setting; whereas an Encore 24'' with the
same size tank uses about 1 refill per hour at the half flow
solution setting (60 min/57 min). It is a distinct advantage to run
the machine longer between refills to eliminate the wasted time
walking back and forth to the janitor's closet and the time it
takes to drain and refill the machine. Thus the present invention
has a clear advantage because it uses less water and therefore
requires fewer tank refills compared with most prior art rotary
scrubbers.
[0036] FIG. 2 is a side view of the present invention, the orbital
scrubber which is generally identified by the numeral 100. The
cleaning head is generally identified by the numeral 102. The
orbital scrubber shown in this and subsequent drawings uses a
cleaning element 116. The term cleaning element 116 as used in this
application includes both removable cleaning pads 117 and removable
cleaning brushes 296, of FIG. 10. Various flexible cleaning pads
117 have been found suitable as a cleaning element 116, including
various pads sold by 3M of Minneapolis, Minn., such as the high
productivity pad 7300, the black stripper pad 720, the eraser pad
3600, the red buffer pad 5100, the white super polish pad 4100 and
the maroon between coats pad. Various removable cleaning brushes
296 may also be suitable as a cleaning element 116.
[0037] The orbital scrubber has a pair of adjustment arms 104 and
106, better seen in FIG. 8, that pivotally engage a left mounting
bracket 108 and a right mounting bracket 110, better seen in the
next figure. The left mounting bracket includes a left yoke 112
that adjustably connects to the left adjustment arm 104. The right
mounting bracket includes a right yoke 114 that adjustably connects
to the right adjustment arm, not shown in this figure. The cleaning
head 102 has an upper position as shown in FIG. 2 so the pad can be
changed or the orbital scrubber can be easily moved from one
location to the other. The cleaning head 102 has a lower position
shown in FIG. 3 for scrubbing the floor surface 30. In the lower
position of FIG. 3, the cleaning element 116 engages the floor
surface 30. A solution conduit 216 runs from the solution tank, not
shown to the cleaning solution distribution tube 172, better seen
4, 5 and 8. Cleaning solution runs by gravity from the solution
tank through the solution conduit 216 to the distribution tube 172
where it drips on the floor and/or the forward edge 120 of the
cleaning element 116.
[0038] The adjustment arms, including the left arm 104 and the
right arm, 106, not shown, raise the cleaning head assembly 102 to
the upper position shown in FIG. 2 and they also lower the cleaning
head assembly to the lower position shown in FIG. 3 in response to
operation of the actuator. Adjustment control mechanisms are
included in the orbital scrubber 100, but are not shown in detail
because they are well know to those skilled in the art. The
adjustment controls to raise and lower the cleaning head are often
mounted on the control panel, not shown, on the rear of the orbital
scrubber.
[0039] In FIG. 2, the operator's hand 118 is gripping the forward
edge 120 of the cleaning element 116 to remove it from the cleaning
head assembly 102. From time to time, cleaning elements wear out or
may be damaged and thus need to be replaced. A new cleaning element
is installed in an opposite manner to the removal process. No tools
are required to remove or install a new cleaning element on the
present invention making it easy to replace a cleaning element.
After the cleaning element has been replaced, the operator actuates
the drive wheels 122 and directs the machine to the work area. The
operator then lowers the cleaning head assembly 102 so the cleaning
element 116 is in contact with the floor surface 30, as shown in
the next figure. The raising and lowering of the cleaning head
assembly 102 is accomplished by the actuator 103. A control panel,
not shown is positioned on the rear of the machine near the
operator. Various control devices, not shown are located on the
control panel including control devices to raise and lower the
cleaning head as is well known to those skilled in the art.
[0040] FIG. 3 is a front view of the cleaning head assembly 102 of
the orbital scrubber of FIG. 2 removed from the rest of the machine
to better show the components of the cleaning head assembly 102. As
previously mentioned, the left mounting bracket 108 includes a left
yoke 112 which connects to the left adjustment arm 104, better seen
in FIG. 2. The right mounting bracket 110 includes a right yoke 114
which connects to the right adjustment arm, not shown. Together,
the adjustment arms raise and lower the cleaning head assembly 102
from the lower scrubbing position of FIG. 3 to the upper position
of FIG. 2. In FIG. 3, the cleaning element 116 is in contact with
the floor surface 30 so the scrubbing process can begin.
[0041] In FIG. 3, the cleaning element 116 is removably connected
to the pad driver 124 by an attaching means 126. A hook and loop
attaching means has been found suitable for this purpose, but any
other attaching means that will removably and securely hold the
cleaning element to the pad driver 124 will suffice. The hook and
loop is particularly suitable because it does not require any tools
to replace the pad. In this figure, the attaching means 126 is
shown as a separate part from the pad driver 124. However, this is
merely a matter of manufacturing convenience. The attaching means
126 may be formed as a single unit with the pad driver 124.
[0042] The brush motor 128 is mounted on the motor mounting plate
130. FIG. 3 shows a pad and not brushes. However, the term "brush
motor" is commonly used in the industry to identify the motor on
the cleaning head regardless of whether brushes or a pad is being
used. The term brush motor also distinguishes the motor on the
cleaning head 102 from the traction motor, not shown, that powers
the drive wheels 122, better seen in the preceding figure.
[0043] Prior art rotary motion scrubbers typically use brushes that
rotate about the centerline of the driveshaft of the brush motor.
The present invention uses a cleaning element 116 that orbits about
the centerline of the driveshaft of the brush motor and hence it is
called an "orbital scrubber". The orbital movement is imparted to
the cleaning element 116 by an eccentric cam 132, better seen in
the next figure. The cleaning element may orbit at speeds exceeding
2000 revolutions per minute which induces vibrations in the
cleaning head 102. These vibrations need to be dampened to enhance
the life of the orbital scrubber 100. A plurality of vibration
dampening elements are positioned between the motor mounting plate
130 and the left and right mounting brackets, 108 and 110. A
plurality of vibration dampening elements is also positioned
between the motor mounting plate 130 and the pad driver 124. The
number, location and type of vibration dampening elements will vary
according to the size of the cleaning element, the size of the
brush motor 128, the weight of the eccentric cam 132 and other
factors. In the present invention, using a 14 by 18 inch pad with a
3/4 HP motor, and a 1.5 lb. eccentric cam, applicants have found
that the model 135-162 rubber spring from Accurate Products, Inc.
of Chicago, Ill. is a suitable vibration dampening element; any
other vibration dampening element that has long service life will
also be suitable. A first upper vibration dampening element 134 and
a second upper vibration dampening element 136, better seen in the
preceding figure, are located between the motor mounting plate 130
and the left mounting bracket 108. A third upper vibration
dampening element 138 and a fourth upper vibration dampening
element 140, not shown, are located between the motor mounting
plate 130 and the right mounting bracket 110.
[0044] A first lower vibration dampening element 142 and a second
lower vibration dampening element 144, better seen in the following
figures are located between the motor mounting plate 130 and the
pad driver 124. A third lower vibration dampening element 146 and
an fourth lower vibration dampening element, not shown, are located
between the motor mounting plate 130 and the pad driver 124. Other
vibration dampening elements and configurations are within the
scope of this invention. The cleaning solution distribution tube
172 is partially shown in the cutaway portions of the motor
mounting plate 130. The cleaning solution distribution tube has a
plurality of holes 218 therein to allow the cleaning solution 43 to
flow out of the tube onto the floor. The holes 218 are shown for
illustrative purposes at the 3 o'clock position, but in the actual
embodiment, they are actually positioned closer to the 5 o'clock
position. The number and size of the holes varies with the width of
the cleaning element 116. Suggested flow rates are discussed
below.
[0045] FIG. 4 is an exploded front view of the cleaning head 102 of
FIG. 3. The brush motor 128 is mounted to the motor mounting plate
130. The first upper vibration dampening element 134 has a threaded
shaft 150 extending from the top and another threaded shaft 152
extending from the bottom of the element. The shaft 150 passes
through a hole, not shown in the left mounting bracket 108 and is
secured by a nut 154. The shaft 152 passes through a hole, not
shown in the motor mounting plate 130 and is secured by a nut 156.
The third upper vibration dampening element 138 has a threaded
shaft 158 extending from the top and another threaded shaft 160
extending from the bottom of the element 138. A nut 162 engages the
threaded shaft, 158 attaching the top of the vibration dampening
element 138 to the right mounting bracket 110. A nut 164 engages
the threaded shaft, 160 attaching the bottom of the vibration
dampening element 138 to the motor mounting plate 130.
[0046] The motor mounting plate 130 has a left lip 166, a right lip
168 and a front lip 170 formed at the outer extremities. These lips
add rigidity to the motor mounting plate and protect the components
housed there under, such as the pad driver 124 and the cleaning
solution distribution tube 172. These lips, 166,168 and 170 do not
function as splash skirts like some of the prior art. The present
invention does not have any splash skirts, because they are not
needed as will be described in greater detail below.
[0047] In order to protect the cleaning head 102 and to avoid
damage to walls and furniture, the head 102 is equipped with two
bumper wheels, 174 and 176. A bolt 178 passes through a hole, not
shown in the motor mounting plate 130 and a hole, not shown in the
center of the left bumper wheel 174. A nut 180 threads on the
extended portion of the bolt 178 to secure the left bumper wheel
174 to the motor mounting plate 130. The left bumper wheel 174 is
free to rotate about the bolt 178. A bolt 182 passes through a
hole, not shown in the motor mounting plate 130 and a hole, not
show in the center of the right bumper wheel 176. A nut 184 threads
on the extended portion of the bolt 182 to secure the right bumper
wheel 176 which is free to rotate about the bolt 182. The left
bumper wheel 174 and the right bumper wheel 176 extend beyond the
motor mounting plate 130, as better seen in FIG. 3. The wheels 174,
176 will bump against walls, furniture and other fixtures to
protect the cleaning head 102 and the scrubber 100 in general. They
will also help prevent scrapes on walls and other fixtures, when
the cleaning head 102 inadvertently contacts a wall or fixture.
[0048] The brush motor 128 causes a drive shaft 186 to rotate. The
drive shaft 186 is mounted off center in the eccentric cam 132. An
extension shaft 188 extends from and is integral with the eccentric
cam 132. A ball bearing assembly 190 is pressed to fit in a journal
192 in the pad driver 124. The extension shaft 188 contacts the
inside raceway of the ball bearing assembly 190. A bolt 189 passes
through a washer 191 and threadably engages a hole, not shown in
the extension shaft 188. When the brush motor 128 is "on" the drive
shaft 186 rotates the eccentric cam which imparts orbital movement
to the pad driver 124 because of the off center position of the
drive shaft 186 in the eccentric cam 132. In other words, the drive
shaft 186 and the extension shaft 188 are not in alignment which
imparts the orbital movement to the pad driver 124.
[0049] The pad driver 124 forms a left front mounting pedestal 194,
a left rear mounting pedestal 196, better seen in FIG. 8, a right
front mounting pedestal 198, and a right rear mounting pedestal
200, better seen in FIG. 8. The first lower vibration dampening
element 142 has an upper threaded shaft 202 extending from the top
thereof and a lower threaded shaft 204 extending from the bottom of
the vibration dampening element 142. The lower threaded shaft 204
threadably engages a threaded hole, not shown in this figure, in
the left front mounting pedestal 194. The upper threaded shaft 202
passes through a hole, not shown in the motor mounting plate 130
and engages a nut 206. The third lower vibration dampening element
146 has an upper threaded shaft 208 extending from the top thereof
and a lower threaded shaft 210 extending from the bottom. The lower
threaded shaft 210 engages a threaded hole, not shown in this
figure, in the right front mounting pedestal 198. The upper
threaded shaft 208 passes through a hole, not shown in the motor
mounting plate 130 and engages a nut 212.
[0050] FIG. 5 is an exploded side view of the cleaning head 102 of
FIG. 3. The distal end 214 of the solution conduit 216 connects to
the cleaning solution distribution tube 172 which has a plurality
of holes 218 therein. The proximal end, not shown of the solution
conduit 216 connects to the solution tank. Cleaning solution flows
by gravity from the solution tank, not shown, through the solution
conduit 216 to the cleaning solution distribution tube 172 where
the cleaning solution drips through the holes 218 onto the floor
surface 30 and the forward edge 120 of the cleaning element 116.
The cleaning solution distribution tube 172 is located proximal the
forward edge 120 of the cleaning element 116 and is secured by a
plurality of brackets on one of which, 220 is shown in this view. A
bolt 222 passes through a hole, not shown in the motor mounting
plate 130 and a hole, not shown in the bracket 220. A nut 224
threads onto the bolt 222 and secures the bracket 220 and thus the
cleaning solution distribution tube 172. The cleaning solution is
applied to the floor and/or the cleaning element by the cleaning
solution distribution tube 172.
[0051] In an alternative embodiment, not shown, holes may be
drilled in the pad driver 124 and the attaching means 126 so the
cleaning solution may be applied to the top of the cleaning element
116. Because cleaning elements are porous, the force of gravity
will draw the cleaning solution through the pad to the floor
30.
[0052] FIG. 6 is a front view of the cleaning head assembly 102 of
FIG. 3 when it encounters an uneven floor surface 226. Unlike prior
art pad drivers used in scrubbers, the flexible pad driver 124 of
the present invention deflects to accommodate the uneven floor
surface 226. Most of the components in the cleaning head assembly
102 are flexible including the cleaning element 116 and the
attaching means 126 which further allows accommodation and bending
to adapt to uneven floor surfaces, an example of which is shown as
226 for illustrative purposes. In addition, the upper and lower
vibration dampening elements are flexible and can be distorted to
further help accommodate to uneven floor surfaces. For illustrative
purposes, the lower right front vibration dampening element 146 is
shown in an exaggerated deflected state to help accommodate the
uneven floor surface 226. Although the motor mounting plate 130 is
rigid, it can tilt somewhat due to the flexibility of the upper
vibration dampening elements, two of which can be seen in this
view, 134 and 138.
[0053] The flexible pad driver 124 is an important feature of the
present invention. The prior art orbital sanders sold by
applicant's assignee require rigid pad drivers in order to smooth
out any high spots on wooden floors. A rigid pad driver sands high
spots continuously without getting into low spots until the wood
floor is smooth and even. A flexible pad driver in the sanding
application would work to exaggerate any high or low spots. The
flexible drive plate 124 of the present invention allows the
orbital scrubber to follow the contour of uneven hard floor
surfaces without putting excessive scrubbing force on high spots in
the floor. Excessive scrubbing force could cause damage to the
finish on high spots on the tile floors. The pad driver must have
enough flex to follow uneven floor contours yet have enough
stiffness to transmit the proper amount of load and scrubbing force
to clean the entire surface area. (The actuator applies downward
force to the flexible pad driver and the cleaning element.) Prior
art floor burnishers, also sold by applicant's assignee require a
floppy pad driver as they are operated at high RPM's (typically
more than 2,000 RPM) in order to polish a floor. The pad driver
must be floppy enough to be sucked down to the floor due to the
vacuum of the high RPM spinning of the pad driver. Only a very
floppy pad driver can maintain contact with an uneven floor surface
while burnishing, since there is no other force pushing or pulling
down on it other than a vacuum. In conclusion, the pad driver can
be too rigid and stiff, like the drivers used in prior art sanders,
or it can be too flexible, like the drivers used in floor
burnishers. The term "flexible pad driver" as used herein means one
that is flexible enough to scrub uneven floor surfaces.
[0054] FIG. 7 is a side view of the cleaning head assembly 102 of
FIG. 3 as it flexes to scrub another uneven floor surface 228. The
left front lower vibration dampening element 142 is shown for
illustrative purposes in an exaggerated deformed state. The
cleaning element 116, the attaching means 126 and the pad driver
124 all flex to accommodate the uneven floor surface 228. Again the
drawing is exaggerated for illustrative purposes. The motor
mounting plate 130 may also tilt slightly to accommodate the uneven
floor surface 228.
[0055] FIG. 8 is an exploded perspective view of the cleaning head
assembly generally identified by the numeral 102 and the front of
the orbital scrubber generally identified by the numeral 100. A
support bracket 300 is mounted in the front of the orbital scrubber
100. The left flange 230 of the support bracket and the right
flange 232 of the support bracket 300 are visible in this view. The
proximal end 302 of the actuator 103 is pivotally mounted on a
support element 304 extending from the support bracket 300.
[0056] An actuator pin 234 passes through a hole 236 in the left
support arm 104, a hole 238 in the distal end of the actuator 103
and a hole 240 in the right support arm 106. Left pins 242 and
right pins 244 pass respectively through holes 246 and 248 in the
opposite ends of the actuator pin 234. A bolt 250 passes through a
hole 252 in the proximal end of the left adjustment arm 104 and a
hole 254 in the left flange 230. A nut 256 secures the threaded
bolt 250. A bolt 258 passes through a hole 260 in the right
adjustment arm 106. A nut 264 secures the threaded bolt 258. Thus
the left adjustment arm 104 and the right adjustment arm 106 are
pivotally mounted to the front end of the orbital scrubber 100 and
their position is controlled by the actuator 103.
[0057] A bolt 266 passes through a hole 268 in the left yoke 112
and a hole 270 in the distal end of the left adjustment arm 104 and
is secured by a nut 272. A bolt 274 passes through a hole 276 in
the right yoke 114 and a hole 278 in the right adjustment arm 106
and is secured by a nut 280. In this fashion, the left adjustment
arm 104 pivotally connects to the left mounting bracket 108 and the
right adjustment arm 106 pivotally connects to the right mounting
bracket 110 which allows the cleaning head assembly 102 to move
from the upper non-scrubbing position of FIG. 2 to the lower
scrubbing position of FIG. 3 when the actuator 103 is operated. As
previously discussed, a control panel 16 is positioned at the rear
of the machine, near the operator and a control mechanism regulates
operation of the actuator 103. In addition to raising and lowering
the cleaning head assembly 102, the actuator 103 applies downward
load on the cleaning head assembly 102 while scrubbing. The amount
of downward load can be adjusted by the control mechanism. Floor
surfaces that are very dirty require more load on the cleaning head
102 for effective cleaning than floor surfaces that are lightly
soiled. Skilled operators will adjust the load on the cleaning head
102 according to the level of dirt on the floor.
[0058] The actuator 103 is adjusted as follows by a control
mechanism, not shown on the control panel 16, better seen in FIG.
1. The operation of the actuator 103 is well known to those skilled
in the art; however, it is briefly explained herein for clarity.
The control mechanism, not shown controls a reversible drive motor
306 operatively connected to a gear box 308. The gear box 308
connects to a threaded shaft, not shown in the actuator 103. When
the motor 306 is operated in one direction it operates the gear box
and the threaded shaft, not shown which lowers the cleaning element
116 of the cleaning head assembly 102 into contact with the floor
as shown in FIG. 3. Further operation of the motor 306 places a
downward load on the cleaning head assembly 102 and the cleaning
element 116. When the motor 306 is operated in the opposite
direction it operates the gear box 308 and the threaded shaft in
the opposite direction, thus raising the cleaning head assembly 102
as shown in FIG. 2 so the cleaning element 116 can be replaced or
the apparatus can be rolled about, for example to refill the
solution tank.
[0059] As previously discussed, four upper vibration dampening
elements, 134, 136, 138 and 140 are positioned between the motor
mounting plate 130 and the mounting brackets, 108 and 110. Four
lower vibration dampening elements, 142,144,146 and 148 are
positioned between the motor mounting plate 130 and the pad driver
124. The eight vibration dampening elements a) help reduce
vibration caused by the orbital movement of the pad driver 124 and
cleaning element 116 and b) help the cleaning element adjust to
uneven floor surfaces 126,128 as illustrated in FIGS. 6 and 7.
[0060] One embodiment of the flexible pad driver 124 has four
mounting pedestals 194, 196, 198 and 200 that connect to the four
lower vibration dampening elements 142, 144, 146 and 148. A central
mounting pedestal 201 is positioned in the center of the flexible
pad driver 124. In one embodiment of the flexible pad driver 124,
each of the mounting pedestals 194, 196, 198, 200 has a plurality
of webs extending from the pedestal. For example, mounting pedestal
194 has a front web 282, a left web 284, a rear web, 286 and a
right web 288. These webs provide structural support for the
pedestal and help direct an even load on the cleaning element 116.
The bumper wheels 174 and 176 have been eliminated from this figure
to better depict other elements of the apparatus.
[0061] FIG. 9 is a cross-section of the vibration dampening element
134. The element 134 is the same as all the other vibration
dampening elements, 136, 138, 140, 142, 144, 146, and 148 shown in
the previous drawings. The vibration dampening element 134 has an
upper threaded shaft 150 and a lower threaded shaft 152. The shaft
150 extends from a support plate 151 and the shaft 152 extends from
a support plate 153. The body 155 of the vibration dampening
element 134 is formed from natural rubber and has a durometer of
40, but other ratings may also be suitable. Applicant has
determined that a rubber spring, model number 135-162 manufactured
by Accurate Products, Inc. of Chicago, Ill. is suitable for this
application. Man-made elastomers may also be suitable as well as
other rubber springs from other manufacturers. In some
applications, metal springs may also be suitable and are included
in the definition of "vibration dampening element" as used in this
application. Other types of vibration dampening elements may also
be suitable as long as they have some degree of flexibility to
allow the pad driver to adjust to uneven floor surfaces.
[0062] Table 1 below compares various features of the prior art
BP-18 orbital scrubber with a 6''.times.18'' cleaning element, the
prior art Encore 17 rotary scrubber with a 17'' diameter rotary
brush, the present invention having a 14''.times.18'' cleaning
element, the prior art Encore 2426 rotary scrubber with two 13''
diameter rotary brushs and the present invention having a
14''.times.24'' cleaning element. The revolutions per spot are one
way to gage the cleaning effectiveness of a machine. Table 1 makes
it clear that the present invention has substantially more
revolutions per spot than these prior art scrubbers. TABLE-US-00001
TABLE 1 Maxi- Pad mum Size Pres- Forward (sq sure Speed Rev/ in)
(lb) PSI RPM (ft/s) spot Orbital 252 90 0.4 2250 3 15 Scrubber 14''
.times. 18'' Orbital 336 150 0.4 2250 4 10 Scrubber 14'' .times.
24'' PRIOR ART 108 45 0.4 1600 2 5 BP-18 Orbital 6'' .times. 18''
PRIOR ART 201 90 0.4 200 3 2 Encore 17 Rotary 17'' Diameter PRIOR
ART 224 150 0.7 200 4 1 Encore 2426 Rotary 13'' Diameter
Some of the data has been rounded up or down to simplify the
presentation.
[0063] Table 2 below compares cleaning solution flow rates in
various prior art scrubbers and the present invention. Solution
flow rate will determine the solution run time of the scrubber.
Table 2 demonstrates that the present invention with various sized
cleaning elements has a lower flow rate and thus greater solution
run time than these prior art scrubbers. Another bench mark of
comparison is U.S. Pat. No. 6,585,827 assigned to Tennant Company.
This patent states as follows: "One limitation of prior art
scrubbers has been a relatively limited operational run time. For a
typical scrubber with a 32 inch wide scrub swath and 30 gallon
solution tank, the solution distribution rate varies between 0.5
GPM to 1.0 GPM. Run time based on solution capacity is between
approximately 30-40 minutes."
[0064] The solution flow rate of the present invention is between
about 0.008 gal./in./min to about 0.017 gal./in./min. Since flow is
measured in gallons/minutes it can vary depending on the size of
the floor scrubber and width of the scrub head. Therefore, flow
expressed in gallons/minute is not a good indication of the
efficiency of a floor scrubber. Historically, very little attention
has been given to the optimal amount of solution needed to clean a
floor.
[0065] Measuring the usage of solution in gallons/inch/minute gives
a more accurate measure of solution use efficiency. The number of
gallons of solution being used per each inch of scrub head width in
one minute can be used as a measure of efficiency for any width of
scrub head or any size scrubber.
[0066] It has been determined through testing that the optimum
usage of solution for an orbital scrubber is about 0.008 to about
0.017 gallons per inch of head width in one minute. A heavily
soiled floor may require up to about 0.017 gal/in/min and a lightly
soiled floor may require only about 0.008 gal./in./min. Therefore,
for any width of scrub head you will simply need to multiply this
solution flow range times the scrub head width in inches to obtain
the optimum amount of flow in gallons/min for any size scrubber.
This technique eliminates any guess work as to how much solution
should be used by any scrubber with any size width scrub head.
[0067] To calculate the maximum necessary solution flow rate for
the present invention in the 18'' width, multiply the full flow
setting of 0.017 gal/in/min times the brush head width of 18'' to
get the flow rate of 0.31 Gal/min. To calculate the maximum
necessary solution flow rate for the present invention in the 24''
width, multiply the full flow setting of 0.017 gal/in/min times the
brush head width of 24'' to get the flow rate of 0.40 Gal/min. To
calculate the maximum necessary solution flow rate for the present
invention in the 28'' width, multiply the full flow setting of
0.017 gal/in/min times the brush head width of 28'' to get the flow
rate of 0.48 Gal/min. To calculate the maximum necessary solution
flow rate for the present invention in the 32'' width, multiply the
full flow setting of 0.017 gal/in/min times the brush head width of
32'' to get the flow rate of 0.55 Gal/min. The following table
compares the flow rates and usage rates for various theoretical
embodiments of the present invention with various prior art
devices. TABLE-US-00002 TABLE 2 Cleaning Usage Flow Total Area Rate
Rate Solution Area (sq/ft/ (Gal/ (Gal/ Tank Run Time Cleaned min)
in/min) min) (gal) (min) (sq ft) Orbital 259 0.017 0.31 11 77 19985
Scrubber 14'' .times. 18'' Full flow setting Orbital 515 0.017 0.40
20 50 25980 Scrubber 14'' .times. 24'' Full flow setting Orbital
601 0.017 0.48 20 42 25259 14'' .times. 28'' Full flow setting
Orbital 726 0.017 0.55 30 57 41219 Scrubber 14'' .times. 32'' Full
flow setting PRIOR ART 216 0.059 1.1 5 4.7 1022 BP-18 Full flow
setting PRIOR ART 245 0.010 0.18 11 61 14989 Encore 17 Rotary 17''
Diameter Full flow setting PRIOR ART 558 0.028 0.74 20 27 15078
Encore 2426 Rotary 26'' Diameter Full flow setting
[0068] FIG. 10 is a perspective view of a flexible pad driver 124
and a removable cleaning brush generally identified by the numeral
296. The flexible pad driver 124 has a connecting means 126, which
in this figure is a hook and loop device. The removable cleaning
brush 296 includes a flexible plastic or nylon sheet 292 with
bristles 294 extending from one side and a pad 290 located on the
opposite side. The pad 290 removably engages the hook and loop
device or other connecting elements 126 on the pad driver 124. The
removable cleaning brush 296 and the removable cleaning pad 117 are
both referred to as cleaning elements 116 in this application.
[0069] Those skilled in the art know that prior art rotary motion
scrubbers use both brushes and pads as cleaning elements. To the
best of applicant's knowledge, the pad drivers used in prior art
rotary motion scrubbers, like the Encore series, are rigid for both
brushes and cleaning pads. The present invention uses a flexible
pad driver 124 for both removable cleaning pads 117 and removable
cleaning brushes 296 of FIG. 10.
[0070] The present invention will give future designers of
scrubbers for hard floor surfaces a number of design options, not
previously available. With prior art rotary motion scrubbers,
battery run time is not the primary limiting factor in scrubber
design; instead, solution run time is the limiting factor. In other
words, the operator must make several tank refills before the
battery run time ends. In a perfect world, solution run time would
equal battery run time, but no scrubber presently has achieved this
lofty goal including the present invention. However, the present
invention has reduced the number of tank refills to a lower level
than any current rotary motion scrubber, including the Tennant Fast
foam machine. This advantage has been achieved due to the low
cleaning solution consumption rate of the present invention.
[0071] In addition, the present invention has reduced the
consumption of electrical energy, which will also give future
designers a number of options. For example, one brush motor will be
all that is required on the present invention even in larger sizes.
Some conventional rotary scrubbers use two brush motors on larger
scrubbers. This reduces costs and may allow designers to reduce the
battery size, if desired. Smaller batteries may also allow for
enlarged solution and recovery tanks. The reduction in consumption
of electrical energy has been achieved by the high speed orbital
motion of the flexible pad driver along with other design features
discussed herein.
[0072] The present invention can be designed with various features
as discussed above. However, applicant has designed three
theoretical embodiments described below that produce many of the
advantages discussed herein. TABLE-US-00003 TABLE 3 ORBITAL
SCRUBBERS SPECIFICATIONS Cleaning Width 18'' 24'' 32'' Pad Size
14'' .times. 18'' 14'' .times. 24'' 13'' .times. 32'' Pad Size in
Square Inches 252 336 448 Maximum Load 90 lbs. 150 lbs. 220 lbs.
PSI 0.36 0.45 0.49 Brush Speed 2250 RPM 2250 2250 Forward Speed
2.88 Ft./Sec 4.29 4.3 Rev./Spot 15 10.2 10.2 Orbit Diameter 1/4''
1/4'' 1/4'' Power Supply (2)12V130AH WET (2)12V130AH WET
(2)12V330AH WET (2)12V330AH WET (2)12V370AH WET Brush Motor 3/4 HP
3/4 HP 3/4 HP Traction Motor 1/3 HP 1/2 HP 1/2 HP Vacuum Motor 3/4
HP 3/4 HP 3/4 HP Battery Run Time 156 min. 396 min. 404 min. Flow
(full solution setting) 0.14 (gal/in/min) 0.40 0.53 Usage (full
solution setting) .017 (gal/in/min) .0165 0.017 Tank Size 11 gal.
20 gal. 30 gal. Solution Run Time 77 min. 50 min. 57 min. Total
Area Cleaned 19,985 sq. ft. 25,980 sq. ft. 38,970 sq. ft. Weight
w/Batteries 342 871 1038 Weight w/Batteries and Solution 419 1011
1248
* * * * *