CROSS-REFERENCE TO RELATED APPLICATION
BACKGROUND
[0002] Extraction cleaning machines are known for deep cleaning carpets and other fabric
surfaces such as upholstery. Most carpet extractors comprise a fluid delivery system,
a fluid recovery system, and, optionally, an agitation system. The fluid delivery
system typically comprises one or more fluid supply tanks for storing cleaning fluid,
a fluid distributor for applying the cleaning fluid to the surface to be cleaned,
and a fluid supply conduit for supplying the fluid from the supply tank to the fluid
distributor. The fluid recovery system typically comprises a recovery tank, a suction
nozzle adjacent to the surface to be cleaned and in fluid communication with the recovery
tank through a working air conduit, and a vacuum source in fluid communication with
the working air conduit to draw cleaning fluid from the surface to be cleaned through
the nozzle and working air conduit into the recovery tank. The agitation system can
include an agitator element for scrubbing the surface to be cleaned, an optional drive
means, and selective control means. The agitation system can include a fixed or driven
agitator element that can comprise a brush, pad, sponge, cloth, and the like. The
agitation system can also include driving and control means including motors, turbines,
belts, gears, switches, sensors, and the like. See, for example,
U.S. Patent No. 6,131,237 to Kasper et al. and
U.S. Patent No. 7,073,226 to Lenkiewicz et al.
BRIEF SUMMARY
[0003] According to an embodiment of the invention, a method of cleaning a carpet segment
of relatively rectangular configuration defined by a first edge, a second edge and
opposite side edges comprises: (a) applying a liquid cleaning solution to the carpet
segment in a narrow band that extends between the side edges and moves between the
first and second edges, (b) applying suction in a narrow band that extends between
the side edges and moves between the first and second edges, (c) repeating act (a),
and (d) repeating act (b). The acts (a), (b), (c) and (d) can be carried out successively
with an end of a preceding act defining a beginning of a subsequent act.
[0004] According to another embodiment of the invention, the movement of the cleaning solution
narrow band in act (a) and the movement of the suction narrow band in act (b) are
in opposite directions.
[0005] In yet another embodiment, the method can further comprise mechanically agitating
the carpet segment during movement of the suction narrow band in acts (b) and (d).
[0006] In another embodiment, the method can further comprise heating the liquid cleaning
solution prior to applying the liquid cleaning solution in acts (a) and (c).
[0007] According to another embodiment of the invention, the acts (a) through (d) are carried
out with an extraction machine.
[0008] In yet another embodiment, a method of cleaning a carpet segment of relatively rectangular
configuration defined by a first edge, a second edge and opposite side edges comprises:
(a) applying a liquid cleaning solution to the carpet segment in a narrow band that
extends between the side edges and moves between the first and second edges, (b) repeating
act (a), (c) repeating act (a), and (d) applying suction in a narrow band that extends
between the side edges and moves between the first and second edges. The acts (a),
(b), (c) and (d) can be carried out successively with an end of a preceding act defining
a beginning of a subsequent act.
[0009] According to another embodiment of the invention, the movement of the cleaning solution
narrow band in act (a) and the movement of the cleaning solution narrow band in act
(b) are in opposite directions.
[0010] According to another embodiment of the invention, the movement of the cleaning solution
narrow band in act (a) and the movement of the cleaning solution narrow band in act
(c) are in the same direction.
[0011] According to another embodiment of the invention, the movement of the cleaning solution
narrow band in act (a) and the movement of the suction narrow band in act (d) are
in opposite directions.
[0012] In yet another embodiment, the method can further comprise mechanically agitating
the carpet segment during movement of the suction narrow band in act (d).
[0013] In another embodiment, the method can further comprise heating the liquid cleaning
solution prior to applying the liquid cleaning solution in acts (a), (b), and (c).
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In the drawings:
FIG. 1 is a schematic of an extraction cleaning machine according to a first embodiment
of the invention.
FIG. 2 is a flowchart illustrating a method of use of an extraction cleaning machine
according to a second embodiment of the invention
FIG. 3 is a flowchart illustrating a method of use of an extraction cleaning machine
according to a third embodiment of the invention.
DETAILED DESCRIPTION
[0015] The embodiments of the invention relate to methods of sequencing wet and dry strokes
of an extraction cleaning machine, often referred to as an extractor or deep cleaner,
for cleaning carpets and other soft surfaces. The methods can be used with any suitable
extractor, non-limiting examples of which include commonly assigned
U.S. Patent No. 6,131,237 to Kasper et al.,
U.S. Patent No. 7,784,148 to Lenkiewicz et al., and
U.S. Patent No. 7,320,149 to Huffman et al., which are incorporated herein by reference in their entirety. While the embodiments
of the invention are described in the context of cleaning carpets, it will be understood
that the embodiments of the invention are also suitable for use with any suitable
soft surface, non-limiting examples of which include rugs, upholstery and drapes.
[0016] Figure 1 is a schematic of an extractor 10 suitable for use with the embodiments
of the method. Any suitable type of extractor having a fluid delivery and recovery
system can be used with the embodiments of the invention described herein. The details
of the extractor are not germane to the invention; only those components necessary
for a complete understanding of the embodiment of the invention are described.
[0017] The extractor 10 includes a fluid delivery system comprising a first cleaning fluid
supply 12 and a second cleaning fluid supply 14 storing first and second cleaning
fluids, respectively. The first and second cleaning fluid supplies 12, 14 can include
a refillable tank, container and/or bladder. The first and second cleaning fluids
can comprise any suitable cleaning fluid, including, but not limited to, water, concentrated
and/or diluted detergent, stain remover, odor remover and the like. For example, the
first cleaning fluid can be water, and the second cleaning fluid can be a concentrated
detergent. Although not illustrated, other supply tanks or containers can be provided
such that the fluid delivery system delivers cleaning fluid from separate tanks or
containers that contain the same or different concentrations or compositions of cleaning
fluid.
[0018] The first and second cleaning fluid supplies 12, 14 can be fluidly coupled with a
mixing/metering assembly 16 through respective first and second cleaning fluid supply
lines 18, 20. The flow of fluid from the first and second cleaning fluid supplies
12, 14 through the first and second cleaning fluid supply lines 18, 20 to the mixing/metering
assembly 16 can be controlled by first and second valve mechanisms 22, 24, respectively.
The first and second cleaning fluids can be optionally mixed by the mixing/metering
assembly 16 to provide a cleaning solution to a spray assembly 26 for distributing
the cleaning solution onto the surface to be cleaned. The spray assembly 26 can include
one or more sprayers, such as those described in
U.S. Patent No. 7,784,148 to Lenkiewicz et al. referenced above.
[0019] The fluid delivery system also includes an optional heater 28 and a pump assembly
30. The heater 28 can be any suitable heater configured to heat fluids, such as an
in-line heater. The pump assembly 30 has a first inlet in fluid communication with
the mixing/metering assembly 16 and an outlet in fluid communication with an inlet
of the spray assembly 26. The pump assembly 30 is operatively connected to a motor/fan
assembly 32 for operation of a primer stack portion thereof, as described in the aforementioned
Kasper patent. Alternatively, the pump can comprise a conventional solenoid pump.
[0020] The fluid recovery system comprises a recovery chamber or tank 34 which is used to
store spent cleaning solution and debris that is recovered from the surface to be
cleaned. A nozzle assembly 36 is in fluid communication with the recovery tank 34
for ingesting spent cleaning solution and debris for collection within the recovery
tank 34. The nozzle assembly 36 can be part of a foot assembly (not shown) configured
to be positioned adjacent the surface to be cleaned during use of the extractor 10.
The foot assembly can further include additional components such as an agitator assembly
comprising one or more agitators, such as a brush roll, for example, for agitating
and providing mechanical cleaning action to the surface to be cleaned. The motor and
fan assembly 32 is fluidly coupled with the nozzle assembly 36 for providing suction
to draw the spent cleaning solution and debris on the surface being cleaned through
the nozzle assembly 36 and into the recover chamber 34. Air drawn into the fluid recovery
system through the nozzle assembly 36 is drawn through the motor and fan assembly
32 before being exhausted from the extractor 10.
[0021] The extractor 10 can also include a control system 38 for operably controlling the
various components of the extractor 10, such as the first and second valve mechanisms
22, 24, the mixing/metering assembly 16, the pump 28, the heater 30 and the motor/fan
assembly 32, for example. The extractor 10 can also include an actuator 40, such as
a button or trigger, which can be selectively actuated to control the delivery of
cleaning solution to the surface to be cleaned.
[0022] In use, upon actuation of the actuator 40 by a user, the control system 38 can control
the first and second valve mechanisms 22, 24 to supply the first and second cleaning
fluids to the mixing/metering assembly 16 to generate a cleaning solution. The control
system 38 can further control the pump 28 and optionally the heater 30 to provide
the cleaning solution to the spray assembly 26 for application to the surface to be
cleaned. The control system 38 can be configured to control the motor/fan assembly
32 such that during application of the cleaning solution, suction is not applied through
the nozzle assembly 36. Alternatively, the control system 38 can be configured to
apply suction during the application of the cleaning solution. Upon release of the
actuator 40, the control system 38 can control the components of the extractor 10
to cease dispensing of the cleaning solution through the spray assembly 26. The spent
cleaning solution and debris on the surface being cleaned can be removed by suction
through the nozzle assembly 36 and stored in the recovery chamber 34 for later disposal
by the user. Suction through the nozzle assembly 36 can be initiated automatically
by the control system 38 upon release of the actuator 40, manually by the user through
a second actuator operably coupled with the motor/fan assembly 32, or suction can
be automatically applied by the control system 38.
[0023] Figure 2 illustrates a method 100 of use of the extractor 10 for cleaning a surface
to be cleaned, such as an area of carpet. The methods of the embodiments of the invention
are described with respect to a "stroke" of the extractor 10. As used herein, a stroke
refers to movement of the extractor 10 relative to the surface being cleaned in a
single direction, with or without the distribution of cleaning solution, from the
perspective of a user positioned behind the extractor 10. A "forward stroke" refers
to movement of the extractor 10 in a forward direction, away from the user. A "reverse
stroke" refers to movement of the extractor 10 in a reverse direction, back towards
the user. A "wet stroke" refers to a stroke, either forward or reverse, during which
the user has actuated the actuator 40 to distribute cleaning solution to the surface
being cleaned. A "dry stroke" refers to a stroke, either forward or reverse, during
which the motor/fan assembly 32 is actuated to provide suction to the nozzle assembly
36 to remove spent cleaning solution and/or debris on the surface being cleaned without
distribution of cleaning solution to the surface. During the dry stroke, the agitator
assembly can also be actuated.
[0024] The method 100 starts with the assumption that the user has filled the first and
second cleaning fluid supplies 12, 14 with the desired cleaning fluids, has positioned
the extractor 10 on the surface to be cleaned and is standing behind the extractor
10. At 102 the user can push the extractor 10 in a forward direction, away from the
user, while actuating the actuator 40 to distribute cleaning solution to the surface,
thus completing a first wet stroke. At 104 the user can pull the extractor 10 in a
reverse direction, back towards the user, over the same general area traversed during
the first wet stroke 102, without actuating the actuator 40, thus completing a first
dry stroke. At 106 the user can again push the extractor 10 in a forward direction,
generally traversing the same area of the surface traversed during the first wet stroke
at 102 and the first dry stroke at 104, while actuating the actuator 40 to distribute
the cleaning solution, thus completing a second wet stroke. At 108 the user can pull
the extractor 10 in a reverse direction, generally traversing the same area of the
surface traversed during the previous strokes at 102, 104 and 106, without actuating
the actuator 40, thus completing a second dry stroke.
[0025] While the method 100 is described as beginning with a forward stroke, it will be
understood that the method 100 can begin with a reverse stroke. The method 100 can
be completed one or more times over the same general area of the surface or may be
used to clean a larger area. For example, the method 100 can be used one or more times
on the same general area to clean a stain or spot on the surface being cleaned. In
another example, the method 100 can be repeated multiple times in the process of cleaning
an entire room.
[0026] The method 100 can be used to clean a carpet segment having a first edge defined
by a position of the extractor 10 at the start of the first wet stroke, a second edge
defined by a position of the extractor 10 at the end of the first wet stroke and opposite
side edges extending between the first and second edges of the carpet segment. The
width of the carpet segment between the opposite side edges can generally be defined
by a width of a cleaning solution spray pattern that is dispensed by the spray assembly
26 and/or a width of the nozzle assembly 36. Alternatively, the width of the carpet
segment can be defined by the width of the extractor foot assembly, with the cleaning
solution spray pattern and the width of the nozzle assembly 36 extending across at
least a portion of the width of the foot assembly. In this manner, movement of the
extractor 10 according to the strokes of the method 100 defines a relatively rectangular
carpet segment that is cleaned according to the method 100.
[0027] Movement between edges of the carpet segment during the method 100 generally defines
a stroke, with each stroke being carried out successively such that an end of one
stroke is followed by a beginning of a second stroke within a relatively short period
of time, on the order of seconds or minutes, for example. In one example, the period
of time between strokes may be based on the amount of time it takes a user to actuate
the actuator 40 to dispense a cleaning solution at the beginning of a wet stroke and
provide momentum to move the extractor 10 and/or the amount of time it takes a user
to release the actuator 40 at the end of a wet stroke and reverse the movement of
the extractor 10.
[0028] A distance between the first and second edges of the carpet segment can vary depending
on the user's approach to cleaning the surface to be cleaned. For example, when the
user is cleaning an entire room, the distance between the first and second edges of
the carpet segment may be greater than the distance between the first and second edges
when the user is cleaning only a portion of a room, such as during a spot treatment.
[0029] Figure 3 illustrates a second method 200 of use of the extractor 10 for cleaning
a carpet segment of a surface to be cleaned, such as an area of carpet. The method
200 is similar to the method 100 except for the sequence and ratio of wet and dry
strokes.
[0030] The method 200 starts with the assumption that the user has filled the first and
second cleaning fluid supplies 12, 14 with the desired cleaning fluids, has positioned
the extractor 10 on the surface to be cleaned and is standing behind the extractor
10. At 202 the user can push the extractor 10 in a forward direction, away from the
user, while actuating the actuator 40 to distribute cleaning solution to the surface,
thus completing a first wet stroke. At 204 the user can pull the extractor 10 in a
reverse direction, back towards the user, over the same general area traversed during
the first wet stroke 202, while actuating the actuator 40 to distribute cleaning solution
to the surface, to complete a second wet stroke. At 206 the user can again push the
extractor 10 in a forward direction, generally traversing the same area of the surface
traversed during the first and second wet strokes at 202 and 204, while actuating
the actuator 40 to distribute the cleaning solution, to complete a third wet stroke.
At 208 the user can pull the extractor 10 in a reverse direction, generally traversing
the same area of the surface traversed during the previous strokes at 202, 204 and
206, without actuating the actuator 40, thus completing a first dry stroke.
[0031] Similar to the first method 100, the method 200 can be completed one or more times
over the same general area of the surface or may be used to clean a larger area. For
example, the method 200 can be used one or more times on the same general area to
clean a stain or spot on the surface being cleaned. In another example, the method
200 can be repeated multiple times in the process of cleaning an entire room.
[0032] The methods 100 and 200 provide different cleaning stroke sequences that can be used
with an extractor to provide improved cleaning performance compared to the standard
sequence of cleaning strokes used with an extractor, as illustrated by the test results
provided below.
Cleaning Performance Evaluation
Methods
[0033] ASTM International has proposed a test method for a laboratory test for determining
the relative carpet cleaning effectiveness of a wet extraction cleaning system when
tested under standard conditions titled "
DRAFT Test Method for Measuring the Carpet Cleaning Effectiveness of Wet Extraction
Cleaners," dated January 20, 2010. The cleaning system is defined as a wet extraction appliance coupled with its included
or recommended chemical cleaning formula. The proposed standard determines the carpet
cleaning effectiveness based on a standard cleaning method that includes two wet strokes
followed by two dry strokes ("two wet/two dry strokes").
[0034] The carpet cleaning effectiveness of three different commercially available extraction
cleaning systems was tested according to the ASTM draft standard using the two wet/two
dry strokes cleaning method outlined in the proposed standard. The cleaning effectiveness
was also tested using the method 100 and 200 of Figures 2 and 3 according to the ASTM
draft standard in place of the two wet/two dry strokes standard cleaning method to
compare the cleaning effectiveness of the methods 100 and 200 with the standard method.
[0035] The amount of water retained ("water retention") by the carpet after cleaning according
to the ASTM draft standard using each of the different cleaning methods was determined
by weighing the carpet test sample before and after cleaning.
Extraction Cleaning Systems
[0036] The three extraction cleaning systems tested include:
- 1) BISSELL® Lift-Off® Deep Cleaning System with the BISSELL® 2X Professional Deep Cleaning formula ("BISSELL® Lift-Off®").
- 2) BISSELL® Proheat® 2X 9200 Deep Cleaning System with the BISSELL® 2X Professional Deep Cleaning formula ("BISSELL® Proheat®").
- 3) Hoover® Max Extract® 60 with the Hoover® 2X Concentrate Deep Cleansing formula ("Hoover® Max Extract®").
Test Results
[0037] Charts 1-7 illustrate test data obtained for the three extraction systems listed
above, BISSELL
® Lift-Off
®, BISSELL
® Proheat
®, and Hoover
® Max Extract
® according to the ASTM draft standard using each of the different cleaning methods,
the ASTM standard cleaning method and the methods 100 and 200 of Figures 2 and 3.
[0040] As can be seen in Charts 1-6, the sequencing of the wet and dry strokes used during
an extraction cleaning method effects the carpet cleaning effectiveness of the BISSELL
® Lift-Off
®, BISSELL
® Proheat
®, and Hoover
® Max Extract
® extraction cleaning systems. Referring now to Charts 1-3, in general, the average
percent clean for 1 wet 1 dry/ 1 wet 1 dry (method 100) and 3 wet/1 dry (method 200)
cleaning methods is greater than the standard 2 wet/2 dry cleaning method for all
three extraction cleaning systems when starting cleaning with the lay of the carpet.
As illustrated in Charts 4-6, in general, ΔE(s-e) is greater for the 1 wet 1 dry/
1 wet 1 dry (method 100) and 3 wet/1 dry (method 200) cleaning methods than the standard
2 wet/2 dry cleaning method for all three extraction cleaning systems both with and
against the lay of the carpet. This data suggests that the 1 wet 1 dry/ 1 wet 1 dry
(method 100) and 3 wet/1 dry (method 200) cleaning methods are on par and often better
than the standard 2 wet/2 dry cleaning method for cleaning carpets.
[0041] Chart 7 illustrates the average amount of liquid retained by the carpet when cleaned
using each three extraction cleaning system for each cleaning method with and against
the lay of the carpet.

[0042] As can be seen in Chart 7, while each of the three cleaning methods includes four
strokes, each method results in different amounts of liquid retained by the carpet.
For example, while the standard 2 wet/2 dry method and method 100 of 1 wet 1 dry/I
wet 1dry both comprise two wet strokes and 2 dry strokes, the sequencing effects the
amount of liquid retained by the carpet, with the method 100 resulting in an increase
in the amount of retained liquid compared to the standard method. The method 200 of
3 wet/1 dry has four strokes total, the same as the standard method and method 100,
however the method 200 has 3 wet strokes and 1 dry, resulting in more liquid retained
by the carpet than either the standard method or method 100.
[0043] Charts 8 and 9 illustrate the test data obtained for the BISSELL
® Lift-Off
® extractor used with the BISSELL
® 2X Professional Deep Cleaning formula and the BISSELL
® 2X Fiber Cleansing formula according to the ASTM draft standard using each of the
different cleaning methods, the ASTM standard cleaning method and the methods 100
and 200 of Figures 2 and 3.

[0044] As can be seen in Charts 8 and 9, even when different cleaning formulas are used
with the extractor, the sequencing and ratio of wet and dry strokes in the cleaning
method affects the cleaning effectiveness of the extraction cleaning system.
[0045] The results shown herein illustrate the effect of the sequencing and the ratio of
wet and dry strokes in the cleaning effectiveness of an extraction cleaning system.
Even when the total number of strokes in the cleaning method is the same, the cleaning
effectiveness and the amount of liquid retained by the carpet varies depending on
the sequencing and the number of wet and dry strokes. This information can be provided
to a user in the form of an instructional manual or a label on the machine such that
the user can make an informed decision on how to use the extraction cleaning system
to clean the carpet to meet the needs of the user.
[0046] For example, if the user only desires a normal level of cleaning effectiveness and
low liquid retention, the standard 2 wet/2 dry method can be used. Alternatively,
if the user desires a higher level of cleaning effectiveness and a slightly greater
amount of liquid retention is acceptable, then the user can use the method 100 of
1 wet 1 dry/ 1 wet 1 dry. In a third option, if the user desires a higher level of
cleaning effectiveness and is not concerned with the amount of retained liquid, the
user can use the method 200 of 3 wet/1 dry. The user can use additional dry strokes
as needed following the method 200 or any of the methods described herein to suction
additional liquid from the surface to decrease the amount of liquid retained by the
surface.
[0047] To the extent not already described, the different features and structures of the
various embodiments may be used in combination with each other as desired. That one
feature may not be illustrated in all of the embodiments is not meant to be construed
that it cannot be, but is done for brevity of description. Thus, the various features
of the different embodiments may be mixed and matched as desired to form new embodiments,
whether or not the new embodiments are expressly described.
[0048] While the invention has been specifically described in connection with certain specific
embodiments thereof, it is to be understood that this is by way of illustration and
not of limitation. Reasonable variation and modification are possible within the scope
of the forgoing disclosure and drawings without departing from the spirit of the invention
which is defined in the appended claims.
1. A method of cleaning a carpet segment of relatively rectangular configuration defined
by a first edge, a second edge and opposite side edges, the method comprising:
(a) applying a liquid cleaning solution to the carpet segment in a narrow band that
extends between the side edges and moves between the first and second edges;
(b) applying suction in a narrow band that extends between the side edges and moves
between the first and second edges;
(c) repeating act (a); and
(d) repeating act (b);
wherein acts (a), (b), (c) and (d) are carried out successively with an end of a preceding
act defining a beginning of a subsequent act.
2. The method of claim 1 wherein the movement of the cleaning solution narrow band in
act (a) and the movement of the suction narrow band in act (b) are in opposite directions.
3. The method of claim 1, further comprising mechanically agitating the carpet segment
during the movement of the suction narrow band in acts (b) and (d).
4. The method of claim 1, further comprising heating the liquid cleaning solution prior
to applying the liquid cleaning solution in acts (a) and (c).
5. The method of claim 1 wherein the acts (a) through (d) are carried out with an extraction
machine.
6. A method of cleaning a carpet segment of relatively rectangular configuration defined
by a first edge, a second edge and opposite side edges, the method comprising:
(a) applying a liquid cleaning solution to the carpet segment in a narrow band that
extends between the side edges and moves between the first and second edges;
(b) repeating act (a);
(c) repeating act (a); and
(d) applying suction in a narrow band that extends between the side edges and moves
between the first and second edges;
wherein acts (a), (b), (c) and (d) are carried out successively with an end of a preceding
act defining a beginning of a subsequent act.
7. The method of claim 6 wherein the movement of the cleaning solution narrow band in
act (a) and the movement of the cleaning solution narrow band in act (b) are in opposite
directions.
8. The method of claim 6 wherein the movement of the cleaning solution narrow band in
act (a) and the movement of the cleaning solution narrow band in act (c) are in the
same direction.
9. The method of claim 6 wherein the movement of the cleaning solution narrow band in
act (a) and the movement of the suction narrow band in act (d) are in opposite directions.
10. The method of claim 6, further comprising mechanically agitating the carpet segment
during the movement of the suction narrow band in act (d).
11. The method of claim 6, further comprising heating the liquid cleaning solution prior
to applying the liquid cleaning solution in acts (a), (b) and (c).
12. The method of claim 6 wherein the acts (a) through (d) are carried out with an extraction
machine.